blob: 62d730d10a51d4b145f8c0a4a4fb0ac6dabe9168 [file] [log] [blame]
// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/crankshaft/hydrogen.h"
#include <memory>
#include <sstream>
#include "src/allocation-site-scopes.h"
#include "src/ast/ast-numbering.h"
#include "src/ast/compile-time-value.h"
#include "src/ast/scopes.h"
#include "src/code-factory.h"
#include "src/crankshaft/hydrogen-bce.h"
#include "src/crankshaft/hydrogen-canonicalize.h"
#include "src/crankshaft/hydrogen-check-elimination.h"
#include "src/crankshaft/hydrogen-dce.h"
#include "src/crankshaft/hydrogen-dehoist.h"
#include "src/crankshaft/hydrogen-environment-liveness.h"
#include "src/crankshaft/hydrogen-escape-analysis.h"
#include "src/crankshaft/hydrogen-gvn.h"
#include "src/crankshaft/hydrogen-infer-representation.h"
#include "src/crankshaft/hydrogen-infer-types.h"
#include "src/crankshaft/hydrogen-load-elimination.h"
#include "src/crankshaft/hydrogen-mark-unreachable.h"
#include "src/crankshaft/hydrogen-osr.h"
#include "src/crankshaft/hydrogen-range-analysis.h"
#include "src/crankshaft/hydrogen-redundant-phi.h"
#include "src/crankshaft/hydrogen-removable-simulates.h"
#include "src/crankshaft/hydrogen-representation-changes.h"
#include "src/crankshaft/hydrogen-sce.h"
#include "src/crankshaft/hydrogen-store-elimination.h"
#include "src/crankshaft/hydrogen-uint32-analysis.h"
#include "src/crankshaft/lithium-allocator.h"
#include "src/crankshaft/typing.h"
#include "src/field-type.h"
#include "src/full-codegen/full-codegen.h"
#include "src/globals.h"
#include "src/ic/call-optimization.h"
#include "src/ic/ic.h"
// GetRootConstructor
#include "src/ic/ic-inl.h"
#include "src/isolate-inl.h"
#include "src/objects/map.h"
#include "src/runtime/runtime.h"
#if V8_TARGET_ARCH_IA32
#include "src/crankshaft/ia32/lithium-codegen-ia32.h" // NOLINT
#elif V8_TARGET_ARCH_X64
#include "src/crankshaft/x64/lithium-codegen-x64.h" // NOLINT
#elif V8_TARGET_ARCH_ARM64
#include "src/crankshaft/arm64/lithium-codegen-arm64.h" // NOLINT
#elif V8_TARGET_ARCH_ARM
#include "src/crankshaft/arm/lithium-codegen-arm.h" // NOLINT
#elif V8_TARGET_ARCH_PPC
#include "src/crankshaft/ppc/lithium-codegen-ppc.h" // NOLINT
#elif V8_TARGET_ARCH_MIPS
#include "src/crankshaft/mips/lithium-codegen-mips.h" // NOLINT
#elif V8_TARGET_ARCH_MIPS64
#include "src/crankshaft/mips64/lithium-codegen-mips64.h" // NOLINT
#elif V8_TARGET_ARCH_S390
#include "src/crankshaft/s390/lithium-codegen-s390.h" // NOLINT
#elif V8_TARGET_ARCH_X87
#include "src/crankshaft/x87/lithium-codegen-x87.h" // NOLINT
#else
#error Unsupported target architecture.
#endif
namespace v8 {
namespace internal {
const auto GetRegConfig = RegisterConfiguration::Crankshaft;
class HOptimizedGraphBuilderWithPositions : public HOptimizedGraphBuilder {
public:
explicit HOptimizedGraphBuilderWithPositions(CompilationInfo* info)
: HOptimizedGraphBuilder(info, true) {
SetSourcePosition(info->shared_info()->start_position());
}
#define DEF_VISIT(type) \
void Visit##type(type* node) override { \
SourcePosition old_position = SourcePosition::Unknown(); \
if (node->position() != kNoSourcePosition) { \
old_position = source_position(); \
SetSourcePosition(node->position()); \
} \
HOptimizedGraphBuilder::Visit##type(node); \
if (old_position.IsKnown()) { \
set_source_position(old_position); \
} \
}
EXPRESSION_NODE_LIST(DEF_VISIT)
#undef DEF_VISIT
#define DEF_VISIT(type) \
void Visit##type(type* node) override { \
SourcePosition old_position = SourcePosition::Unknown(); \
if (node->position() != kNoSourcePosition) { \
old_position = source_position(); \
SetSourcePosition(node->position()); \
} \
HOptimizedGraphBuilder::Visit##type(node); \
if (old_position.IsKnown()) { \
set_source_position(old_position); \
} \
}
STATEMENT_NODE_LIST(DEF_VISIT)
#undef DEF_VISIT
#define DEF_VISIT(type) \
void Visit##type(type* node) override { \
HOptimizedGraphBuilder::Visit##type(node); \
}
DECLARATION_NODE_LIST(DEF_VISIT)
#undef DEF_VISIT
};
HCompilationJob::Status HCompilationJob::PrepareJobImpl() {
if (!isolate()->use_optimizer() ||
info()->shared_info()->must_use_ignition_turbo()) {
// Crankshaft is entirely disabled.
return FAILED;
}
// Optimization requires a version of fullcode with deoptimization support.
// Recompile the unoptimized version of the code if the current version
// doesn't have deoptimization support already.
// Otherwise, if we are gathering compilation time and space statistics
// for hydrogen, gather baseline statistics for a fullcode compilation.
bool should_recompile = !info()->shared_info()->has_deoptimization_support();
if (should_recompile || FLAG_hydrogen_stats) {
base::ElapsedTimer timer;
if (FLAG_hydrogen_stats) {
timer.Start();
}
if (!Compiler::EnsureDeoptimizationSupport(info())) {
return FAILED;
}
if (FLAG_hydrogen_stats) {
isolate()->GetHStatistics()->IncrementFullCodeGen(timer.Elapsed());
}
}
DCHECK(info()->shared_info()->has_deoptimization_support());
// Check the whitelist for Crankshaft.
if (!info()->shared_info()->PassesFilter(FLAG_hydrogen_filter)) {
return AbortOptimization(kHydrogenFilter);
}
Scope* scope = info()->scope();
if (LUnallocated::TooManyParameters(scope->num_parameters())) {
// Crankshaft would require too many Lithium operands.
return AbortOptimization(kTooManyParameters);
}
if (info()->is_osr() &&
LUnallocated::TooManyParametersOrStackSlots(scope->num_parameters(),
scope->num_stack_slots())) {
// Crankshaft would require too many Lithium operands.
return AbortOptimization(kTooManyParametersLocals);
}
if (IsGeneratorFunction(info()->shared_info()->kind())) {
// Crankshaft does not support generators.
return AbortOptimization(kGenerator);
}
if (FLAG_trace_hydrogen) {
isolate()->GetHTracer()->TraceCompilation(info());
}
// Optimization could have been disabled by the parser. Note that this check
// is only needed because the Hydrogen graph builder is missing some bailouts.
if (info()->shared_info()->optimization_disabled()) {
return AbortOptimization(
info()->shared_info()->disable_optimization_reason());
}
HOptimizedGraphBuilder* graph_builder =
(FLAG_hydrogen_track_positions || isolate()->is_profiling() ||
FLAG_trace_ic)
? new (info()->zone()) HOptimizedGraphBuilderWithPositions(info())
: new (info()->zone()) HOptimizedGraphBuilder(info(), false);
// Type-check the function.
AstTyper(info()->isolate(), info()->zone(), info()->closure(),
info()->scope(), info()->osr_ast_id(), info()->literal(),
graph_builder->bounds())
.Run();
graph_ = graph_builder->CreateGraph();
if (isolate()->has_pending_exception()) {
return FAILED;
}
if (graph_ == NULL) return FAILED;
if (info()->dependencies()->HasAborted()) {
// Dependency has changed during graph creation. Let's try again later.
return RetryOptimization(kBailedOutDueToDependencyChange);
}
return SUCCEEDED;
}
HCompilationJob::Status HCompilationJob::ExecuteJobImpl() {
DCHECK(graph_ != NULL);
BailoutReason bailout_reason = kNoReason;
if (graph_->Optimize(&bailout_reason)) {
chunk_ = LChunk::NewChunk(graph_);
if (chunk_ != NULL) return SUCCEEDED;
} else if (bailout_reason != kNoReason) {
info()->AbortOptimization(bailout_reason);
}
return FAILED;
}
HCompilationJob::Status HCompilationJob::FinalizeJobImpl() {
DCHECK(chunk_ != NULL);
DCHECK(graph_ != NULL);
{
// Deferred handles reference objects that were accessible during
// graph creation. To make sure that we don't encounter inconsistencies
// between graph creation and code generation, we disallow accessing
// objects through deferred handles during the latter, with exceptions.
DisallowDeferredHandleDereference no_deferred_handle_deref;
Handle<Code> optimized_code = chunk_->Codegen();
if (optimized_code.is_null()) {
if (info()->bailout_reason() == kNoReason) {
return AbortOptimization(kCodeGenerationFailed);
}
return FAILED;
}
RegisterWeakObjectsInOptimizedCode(optimized_code);
info()->SetCode(optimized_code);
}
// Add to the weak list of optimized code objects.
info()->context()->native_context()->AddOptimizedCode(*info()->code());
return SUCCEEDED;
}
HBasicBlock::HBasicBlock(HGraph* graph)
: block_id_(graph->GetNextBlockID()),
graph_(graph),
phis_(4, graph->zone()),
first_(NULL),
last_(NULL),
end_(NULL),
loop_information_(NULL),
predecessors_(2, graph->zone()),
dominator_(NULL),
dominated_blocks_(4, graph->zone()),
last_environment_(NULL),
argument_count_(-1),
first_instruction_index_(-1),
last_instruction_index_(-1),
deleted_phis_(4, graph->zone()),
parent_loop_header_(NULL),
inlined_entry_block_(NULL),
is_inline_return_target_(false),
is_reachable_(true),
dominates_loop_successors_(false),
is_osr_entry_(false),
is_ordered_(false) { }
Isolate* HBasicBlock::isolate() const {
return graph_->isolate();
}
void HBasicBlock::MarkUnreachable() {
is_reachable_ = false;
}
void HBasicBlock::AttachLoopInformation() {
DCHECK(!IsLoopHeader());
loop_information_ = new(zone()) HLoopInformation(this, zone());
}
void HBasicBlock::DetachLoopInformation() {
DCHECK(IsLoopHeader());
loop_information_ = NULL;
}
void HBasicBlock::AddPhi(HPhi* phi) {
DCHECK(!IsStartBlock());
phis_.Add(phi, zone());
phi->SetBlock(this);
}
void HBasicBlock::RemovePhi(HPhi* phi) {
DCHECK(phi->block() == this);
DCHECK(phis_.Contains(phi));
phi->Kill();
phis_.RemoveElement(phi);
phi->SetBlock(NULL);
}
void HBasicBlock::AddInstruction(HInstruction* instr, SourcePosition position) {
DCHECK(!IsStartBlock() || !IsFinished());
DCHECK(!instr->IsLinked());
DCHECK(!IsFinished());
if (position.IsKnown()) {
instr->set_position(position);
}
if (first_ == NULL) {
DCHECK(last_environment() != NULL);
DCHECK(!last_environment()->ast_id().IsNone());
HBlockEntry* entry = new(zone()) HBlockEntry();
entry->InitializeAsFirst(this);
if (position.IsKnown()) {
entry->set_position(position);
} else {
DCHECK(!FLAG_hydrogen_track_positions ||
!graph()->info()->IsOptimizing() || instr->IsAbnormalExit());
}
first_ = last_ = entry;
}
instr->InsertAfter(last_);
}
HPhi* HBasicBlock::AddNewPhi(int merged_index) {
if (graph()->IsInsideNoSideEffectsScope()) {
merged_index = HPhi::kInvalidMergedIndex;
}
HPhi* phi = new(zone()) HPhi(merged_index, zone());
AddPhi(phi);
return phi;
}
HSimulate* HBasicBlock::CreateSimulate(BailoutId ast_id,
RemovableSimulate removable) {
DCHECK(HasEnvironment());
HEnvironment* environment = last_environment();
DCHECK(ast_id.IsNone() ||
ast_id == BailoutId::StubEntry() ||
environment->closure()->shared()->VerifyBailoutId(ast_id));
int push_count = environment->push_count();
int pop_count = environment->pop_count();
HSimulate* instr =
new(zone()) HSimulate(ast_id, pop_count, zone(), removable);
#ifdef DEBUG
instr->set_closure(environment->closure());
#endif
// Order of pushed values: newest (top of stack) first. This allows
// HSimulate::MergeWith() to easily append additional pushed values
// that are older (from further down the stack).
for (int i = 0; i < push_count; ++i) {
instr->AddPushedValue(environment->ExpressionStackAt(i));
}
for (GrowableBitVector::Iterator it(environment->assigned_variables(),
zone());
!it.Done();
it.Advance()) {
int index = it.Current();
instr->AddAssignedValue(index, environment->Lookup(index));
}
environment->ClearHistory();
return instr;
}
void HBasicBlock::Finish(HControlInstruction* end, SourcePosition position) {
DCHECK(!IsFinished());
AddInstruction(end, position);
end_ = end;
for (HSuccessorIterator it(end); !it.Done(); it.Advance()) {
it.Current()->RegisterPredecessor(this);
}
}
void HBasicBlock::Goto(HBasicBlock* block, SourcePosition position,
FunctionState* state, bool add_simulate) {
bool drop_extra = state != NULL &&
state->inlining_kind() == NORMAL_RETURN;
if (block->IsInlineReturnTarget()) {
HEnvironment* env = last_environment();
int argument_count = env->arguments_environment()->parameter_count();
AddInstruction(new(zone())
HLeaveInlined(state->entry(), argument_count),
position);
UpdateEnvironment(last_environment()->DiscardInlined(drop_extra));
}
if (add_simulate) AddNewSimulate(BailoutId::None(), position);
HGoto* instr = new(zone()) HGoto(block);
Finish(instr, position);
}
void HBasicBlock::AddLeaveInlined(HValue* return_value, FunctionState* state,
SourcePosition position) {
HBasicBlock* target = state->function_return();
bool drop_extra = state->inlining_kind() == NORMAL_RETURN;
DCHECK(target->IsInlineReturnTarget());
DCHECK(return_value != NULL);
HEnvironment* env = last_environment();
int argument_count = env->arguments_environment()->parameter_count();
AddInstruction(new(zone()) HLeaveInlined(state->entry(), argument_count),
position);
UpdateEnvironment(last_environment()->DiscardInlined(drop_extra));
last_environment()->Push(return_value);
AddNewSimulate(BailoutId::None(), position);
HGoto* instr = new(zone()) HGoto(target);
Finish(instr, position);
}
void HBasicBlock::SetInitialEnvironment(HEnvironment* env) {
DCHECK(!HasEnvironment());
DCHECK(first() == NULL);
UpdateEnvironment(env);
}
void HBasicBlock::UpdateEnvironment(HEnvironment* env) {
last_environment_ = env;
graph()->update_maximum_environment_size(env->first_expression_index());
}
void HBasicBlock::SetJoinId(BailoutId ast_id) {
int length = predecessors_.length();
DCHECK(length > 0);
for (int i = 0; i < length; i++) {
HBasicBlock* predecessor = predecessors_[i];
DCHECK(predecessor->end()->IsGoto());
HSimulate* simulate = HSimulate::cast(predecessor->end()->previous());
DCHECK(i != 0 ||
(predecessor->last_environment()->closure().is_null() ||
predecessor->last_environment()->closure()->shared()
->VerifyBailoutId(ast_id)));
simulate->set_ast_id(ast_id);
predecessor->last_environment()->set_ast_id(ast_id);
}
}
bool HBasicBlock::Dominates(HBasicBlock* other) const {
HBasicBlock* current = other->dominator();
while (current != NULL) {
if (current == this) return true;
current = current->dominator();
}
return false;
}
bool HBasicBlock::EqualToOrDominates(HBasicBlock* other) const {
if (this == other) return true;
return Dominates(other);
}
int HBasicBlock::LoopNestingDepth() const {
const HBasicBlock* current = this;
int result = (current->IsLoopHeader()) ? 1 : 0;
while (current->parent_loop_header() != NULL) {
current = current->parent_loop_header();
result++;
}
return result;
}
void HBasicBlock::PostProcessLoopHeader(IterationStatement* stmt) {
DCHECK(IsLoopHeader());
SetJoinId(stmt->EntryId());
if (predecessors()->length() == 1) {
// This is a degenerated loop.
DetachLoopInformation();
return;
}
// Only the first entry into the loop is from outside the loop. All other
// entries must be back edges.
for (int i = 1; i < predecessors()->length(); ++i) {
loop_information()->RegisterBackEdge(predecessors()->at(i));
}
}
void HBasicBlock::MarkSuccEdgeUnreachable(int succ) {
DCHECK(IsFinished());
HBasicBlock* succ_block = end()->SuccessorAt(succ);
DCHECK(succ_block->predecessors()->length() == 1);
succ_block->MarkUnreachable();
}
void HBasicBlock::RegisterPredecessor(HBasicBlock* pred) {
if (HasPredecessor()) {
// Only loop header blocks can have a predecessor added after
// instructions have been added to the block (they have phis for all
// values in the environment, these phis may be eliminated later).
DCHECK(IsLoopHeader() || first_ == NULL);
HEnvironment* incoming_env = pred->last_environment();
if (IsLoopHeader()) {
DCHECK_EQ(phis()->length(), incoming_env->length());
for (int i = 0; i < phis_.length(); ++i) {
phis_[i]->AddInput(incoming_env->values()->at(i));
}
} else {
last_environment()->AddIncomingEdge(this, pred->last_environment());
}
} else if (!HasEnvironment() && !IsFinished()) {
DCHECK(!IsLoopHeader());
SetInitialEnvironment(pred->last_environment()->Copy());
}
predecessors_.Add(pred, zone());
}
void HBasicBlock::AddDominatedBlock(HBasicBlock* block) {
DCHECK(!dominated_blocks_.Contains(block));
// Keep the list of dominated blocks sorted such that if there is two
// succeeding block in this list, the predecessor is before the successor.
int index = 0;
while (index < dominated_blocks_.length() &&
dominated_blocks_[index]->block_id() < block->block_id()) {
++index;
}
dominated_blocks_.InsertAt(index, block, zone());
}
void HBasicBlock::AssignCommonDominator(HBasicBlock* other) {
if (dominator_ == NULL) {
dominator_ = other;
other->AddDominatedBlock(this);
} else if (other->dominator() != NULL) {
HBasicBlock* first = dominator_;
HBasicBlock* second = other;
while (first != second) {
if (first->block_id() > second->block_id()) {
first = first->dominator();
} else {
second = second->dominator();
}
DCHECK(first != NULL && second != NULL);
}
if (dominator_ != first) {
DCHECK(dominator_->dominated_blocks_.Contains(this));
dominator_->dominated_blocks_.RemoveElement(this);
dominator_ = first;
first->AddDominatedBlock(this);
}
}
}
void HBasicBlock::AssignLoopSuccessorDominators() {
// Mark blocks that dominate all subsequent reachable blocks inside their
// loop. Exploit the fact that blocks are sorted in reverse post order. When
// the loop is visited in increasing block id order, if the number of
// non-loop-exiting successor edges at the dominator_candidate block doesn't
// exceed the number of previously encountered predecessor edges, there is no
// path from the loop header to any block with higher id that doesn't go
// through the dominator_candidate block. In this case, the
// dominator_candidate block is guaranteed to dominate all blocks reachable
// from it with higher ids.
HBasicBlock* last = loop_information()->GetLastBackEdge();
int outstanding_successors = 1; // one edge from the pre-header
// Header always dominates everything.
MarkAsLoopSuccessorDominator();
for (int j = block_id(); j <= last->block_id(); ++j) {
HBasicBlock* dominator_candidate = graph_->blocks()->at(j);
for (HPredecessorIterator it(dominator_candidate); !it.Done();
it.Advance()) {
HBasicBlock* predecessor = it.Current();
// Don't count back edges.
if (predecessor->block_id() < dominator_candidate->block_id()) {
outstanding_successors--;
}
}
// If more successors than predecessors have been seen in the loop up to
// now, it's not possible to guarantee that the current block dominates
// all of the blocks with higher IDs. In this case, assume conservatively
// that those paths through loop that don't go through the current block
// contain all of the loop's dependencies. Also be careful to record
// dominator information about the current loop that's being processed,
// and not nested loops, which will be processed when
// AssignLoopSuccessorDominators gets called on their header.
DCHECK(outstanding_successors >= 0);
HBasicBlock* parent_loop_header = dominator_candidate->parent_loop_header();
if (outstanding_successors == 0 &&
(parent_loop_header == this && !dominator_candidate->IsLoopHeader())) {
dominator_candidate->MarkAsLoopSuccessorDominator();
}
HControlInstruction* end = dominator_candidate->end();
for (HSuccessorIterator it(end); !it.Done(); it.Advance()) {
HBasicBlock* successor = it.Current();
// Only count successors that remain inside the loop and don't loop back
// to a loop header.
if (successor->block_id() > dominator_candidate->block_id() &&
successor->block_id() <= last->block_id()) {
// Backwards edges must land on loop headers.
DCHECK(successor->block_id() > dominator_candidate->block_id() ||
successor->IsLoopHeader());
outstanding_successors++;
}
}
}
}
int HBasicBlock::PredecessorIndexOf(HBasicBlock* predecessor) const {
for (int i = 0; i < predecessors_.length(); ++i) {
if (predecessors_[i] == predecessor) return i;
}
UNREACHABLE();
}
#ifdef DEBUG
void HBasicBlock::Verify() {
// Check that every block is finished.
DCHECK(IsFinished());
DCHECK(block_id() >= 0);
// Check that the incoming edges are in edge split form.
if (predecessors_.length() > 1) {
for (int i = 0; i < predecessors_.length(); ++i) {
DCHECK(predecessors_[i]->end()->SecondSuccessor() == NULL);
}
}
}
#endif
void HLoopInformation::RegisterBackEdge(HBasicBlock* block) {
this->back_edges_.Add(block, block->zone());
AddBlock(block);
}
HBasicBlock* HLoopInformation::GetLastBackEdge() const {
int max_id = -1;
HBasicBlock* result = NULL;
for (int i = 0; i < back_edges_.length(); ++i) {
HBasicBlock* cur = back_edges_[i];
if (cur->block_id() > max_id) {
max_id = cur->block_id();
result = cur;
}
}
return result;
}
void HLoopInformation::AddBlock(HBasicBlock* block) {
if (block == loop_header()) return;
if (block->parent_loop_header() == loop_header()) return;
if (block->parent_loop_header() != NULL) {
AddBlock(block->parent_loop_header());
} else {
block->set_parent_loop_header(loop_header());
blocks_.Add(block, block->zone());
for (int i = 0; i < block->predecessors()->length(); ++i) {
AddBlock(block->predecessors()->at(i));
}
}
}
#ifdef DEBUG
// Checks reachability of the blocks in this graph and stores a bit in
// the BitVector "reachable()" for every block that can be reached
// from the start block of the graph. If "dont_visit" is non-null, the given
// block is treated as if it would not be part of the graph. "visited_count()"
// returns the number of reachable blocks.
class ReachabilityAnalyzer BASE_EMBEDDED {
public:
ReachabilityAnalyzer(HBasicBlock* entry_block,
int block_count,
HBasicBlock* dont_visit)
: visited_count_(0),
stack_(16, entry_block->zone()),
reachable_(block_count, entry_block->zone()),
dont_visit_(dont_visit) {
PushBlock(entry_block);
Analyze();
}
int visited_count() const { return visited_count_; }
const BitVector* reachable() const { return &reachable_; }
private:
void PushBlock(HBasicBlock* block) {
if (block != NULL && block != dont_visit_ &&
!reachable_.Contains(block->block_id())) {
reachable_.Add(block->block_id());
stack_.Add(block, block->zone());
visited_count_++;
}
}
void Analyze() {
while (!stack_.is_empty()) {
HControlInstruction* end = stack_.RemoveLast()->end();
for (HSuccessorIterator it(end); !it.Done(); it.Advance()) {
PushBlock(it.Current());
}
}
}
int visited_count_;
ZoneList<HBasicBlock*> stack_;
BitVector reachable_;
HBasicBlock* dont_visit_;
};
void HGraph::Verify(bool do_full_verify) const {
base::LockGuard<base::Mutex> guard(isolate()->heap()->relocation_mutex());
AllowHandleDereference allow_deref;
AllowDeferredHandleDereference allow_deferred_deref;
for (int i = 0; i < blocks_.length(); i++) {
HBasicBlock* block = blocks_.at(i);
block->Verify();
// Check that every block contains at least one node and that only the last
// node is a control instruction.
HInstruction* current = block->first();
DCHECK(current != NULL && current->IsBlockEntry());
while (current != NULL) {
DCHECK((current->next() == NULL) == current->IsControlInstruction());
DCHECK(current->block() == block);
current->Verify();
current = current->next();
}
// Check that successors are correctly set.
HBasicBlock* first = block->end()->FirstSuccessor();
HBasicBlock* second = block->end()->SecondSuccessor();
DCHECK(second == NULL || first != NULL);
// Check that the predecessor array is correct.
if (first != NULL) {
DCHECK(first->predecessors()->Contains(block));
if (second != NULL) {
DCHECK(second->predecessors()->Contains(block));
}
}
// Check that phis have correct arguments.
for (int j = 0; j < block->phis()->length(); j++) {
HPhi* phi = block->phis()->at(j);
phi->Verify();
}
// Check that all join blocks have predecessors that end with an
// unconditional goto and agree on their environment node id.
if (block->predecessors()->length() >= 2) {
BailoutId id =
block->predecessors()->first()->last_environment()->ast_id();
for (int k = 0; k < block->predecessors()->length(); k++) {
HBasicBlock* predecessor = block->predecessors()->at(k);
DCHECK(predecessor->end()->IsGoto() ||
predecessor->end()->IsDeoptimize());
DCHECK(predecessor->last_environment()->ast_id() == id);
}
}
}
// Check special property of first block to have no predecessors.
DCHECK(blocks_.at(0)->predecessors()->is_empty());
if (do_full_verify) {
// Check that the graph is fully connected.
ReachabilityAnalyzer analyzer(entry_block_, blocks_.length(), NULL);
DCHECK(analyzer.visited_count() == blocks_.length());
// Check that entry block dominator is NULL.
DCHECK(entry_block_->dominator() == NULL);
// Check dominators.
for (int i = 0; i < blocks_.length(); ++i) {
HBasicBlock* block = blocks_.at(i);
if (block->dominator() == NULL) {
// Only start block may have no dominator assigned to.
DCHECK(i == 0);
} else {
// Assert that block is unreachable if dominator must not be visited.
ReachabilityAnalyzer dominator_analyzer(entry_block_,
blocks_.length(),
block->dominator());
DCHECK(!dominator_analyzer.reachable()->Contains(block->block_id()));
}
}
}
}
#endif
HConstant* HGraph::GetConstant(SetOncePointer<HConstant>* pointer,
int32_t value) {
if (!pointer->is_set()) {
// Can't pass GetInvalidContext() to HConstant::New, because that will
// recursively call GetConstant
HConstant* constant = HConstant::New(isolate(), zone(), NULL, value);
constant->InsertAfter(entry_block()->first());
pointer->set(constant);
return constant;
}
return ReinsertConstantIfNecessary(pointer->get());
}
HConstant* HGraph::ReinsertConstantIfNecessary(HConstant* constant) {
if (!constant->IsLinked()) {
// The constant was removed from the graph. Reinsert.
constant->ClearFlag(HValue::kIsDead);
constant->InsertAfter(entry_block()->first());
}
return constant;
}
HConstant* HGraph::GetConstant0() {
return GetConstant(&constant_0_, 0);
}
HConstant* HGraph::GetConstant1() {
return GetConstant(&constant_1_, 1);
}
HConstant* HGraph::GetConstantMinus1() {
return GetConstant(&constant_minus1_, -1);
}
HConstant* HGraph::GetConstantBool(bool value) {
return value ? GetConstantTrue() : GetConstantFalse();
}
#define DEFINE_GET_CONSTANT(Name, name, constant, type, htype, boolean_value, \
undetectable) \
HConstant* HGraph::GetConstant##Name() { \
if (!constant_##name##_.is_set()) { \
HConstant* constant = new (zone()) HConstant( \
Unique<Object>::CreateImmovable(isolate()->factory()->constant()), \
Unique<Map>::CreateImmovable(isolate()->factory()->type##_map()), \
false, Representation::Tagged(), htype, true, boolean_value, \
undetectable, ODDBALL_TYPE); \
constant->InsertAfter(entry_block()->first()); \
constant_##name##_.set(constant); \
} \
return ReinsertConstantIfNecessary(constant_##name##_.get()); \
}
DEFINE_GET_CONSTANT(Undefined, undefined, undefined_value, undefined,
HType::Undefined(), false, true)
DEFINE_GET_CONSTANT(True, true, true_value, boolean, HType::Boolean(), true,
false)
DEFINE_GET_CONSTANT(False, false, false_value, boolean, HType::Boolean(), false,
false)
DEFINE_GET_CONSTANT(Hole, the_hole, the_hole_value, the_hole, HType::None(),
false, false)
DEFINE_GET_CONSTANT(Null, null, null_value, null, HType::Null(), false, true)
DEFINE_GET_CONSTANT(OptimizedOut, optimized_out, optimized_out, optimized_out,
HType::None(), false, false)
#undef DEFINE_GET_CONSTANT
#define DEFINE_IS_CONSTANT(Name, name) \
bool HGraph::IsConstant##Name(HConstant* constant) { \
return constant_##name##_.is_set() && constant == constant_##name##_.get(); \
}
DEFINE_IS_CONSTANT(Undefined, undefined)
DEFINE_IS_CONSTANT(0, 0)
DEFINE_IS_CONSTANT(1, 1)
DEFINE_IS_CONSTANT(Minus1, minus1)
DEFINE_IS_CONSTANT(True, true)
DEFINE_IS_CONSTANT(False, false)
DEFINE_IS_CONSTANT(Hole, the_hole)
DEFINE_IS_CONSTANT(Null, null)
#undef DEFINE_IS_CONSTANT
HConstant* HGraph::GetInvalidContext() {
return GetConstant(&constant_invalid_context_, 0xFFFFC0C7);
}
bool HGraph::IsStandardConstant(HConstant* constant) {
if (IsConstantUndefined(constant)) return true;
if (IsConstant0(constant)) return true;
if (IsConstant1(constant)) return true;
if (IsConstantMinus1(constant)) return true;
if (IsConstantTrue(constant)) return true;
if (IsConstantFalse(constant)) return true;
if (IsConstantHole(constant)) return true;
if (IsConstantNull(constant)) return true;
return false;
}
HGraphBuilder::IfBuilder::IfBuilder() : builder_(NULL), needs_compare_(true) {}
HGraphBuilder::IfBuilder::IfBuilder(HGraphBuilder* builder)
: needs_compare_(true) {
Initialize(builder);
}
HGraphBuilder::IfBuilder::IfBuilder(HGraphBuilder* builder,
HIfContinuation* continuation)
: needs_compare_(false), first_true_block_(NULL), first_false_block_(NULL) {
InitializeDontCreateBlocks(builder);
continuation->Continue(&first_true_block_, &first_false_block_);
}
void HGraphBuilder::IfBuilder::InitializeDontCreateBlocks(
HGraphBuilder* builder) {
builder_ = builder;
finished_ = false;
did_then_ = false;
did_else_ = false;
did_else_if_ = false;
did_and_ = false;
did_or_ = false;
captured_ = false;
pending_merge_block_ = false;
split_edge_merge_block_ = NULL;
merge_at_join_blocks_ = NULL;
normal_merge_at_join_block_count_ = 0;
deopt_merge_at_join_block_count_ = 0;
}
void HGraphBuilder::IfBuilder::Initialize(HGraphBuilder* builder) {
InitializeDontCreateBlocks(builder);
HEnvironment* env = builder->environment();
first_true_block_ = builder->CreateBasicBlock(env->Copy());
first_false_block_ = builder->CreateBasicBlock(env->Copy());
}
HControlInstruction* HGraphBuilder::IfBuilder::AddCompare(
HControlInstruction* compare) {
DCHECK(did_then_ == did_else_);
if (did_else_) {
// Handle if-then-elseif
did_else_if_ = true;
did_else_ = false;
did_then_ = false;
did_and_ = false;
did_or_ = false;
pending_merge_block_ = false;
split_edge_merge_block_ = NULL;
HEnvironment* env = builder()->environment();
first_true_block_ = builder()->CreateBasicBlock(env->Copy());
first_false_block_ = builder()->CreateBasicBlock(env->Copy());
}
if (split_edge_merge_block_ != NULL) {
HEnvironment* env = first_false_block_->last_environment();
HBasicBlock* split_edge = builder()->CreateBasicBlock(env->Copy());
if (did_or_) {
compare->SetSuccessorAt(0, split_edge);
compare->SetSuccessorAt(1, first_false_block_);
} else {
compare->SetSuccessorAt(0, first_true_block_);
compare->SetSuccessorAt(1, split_edge);
}
builder()->GotoNoSimulate(split_edge, split_edge_merge_block_);
} else {
compare->SetSuccessorAt(0, first_true_block_);
compare->SetSuccessorAt(1, first_false_block_);
}
builder()->FinishCurrentBlock(compare);
needs_compare_ = false;
return compare;
}
void HGraphBuilder::IfBuilder::Or() {
DCHECK(!needs_compare_);
DCHECK(!did_and_);
did_or_ = true;
HEnvironment* env = first_false_block_->last_environment();
if (split_edge_merge_block_ == NULL) {
split_edge_merge_block_ = builder()->CreateBasicBlock(env->Copy());
builder()->GotoNoSimulate(first_true_block_, split_edge_merge_block_);
first_true_block_ = split_edge_merge_block_;
}
builder()->set_current_block(first_false_block_);
first_false_block_ = builder()->CreateBasicBlock(env->Copy());
}
void HGraphBuilder::IfBuilder::And() {
DCHECK(!needs_compare_);
DCHECK(!did_or_);
did_and_ = true;
HEnvironment* env = first_false_block_->last_environment();
if (split_edge_merge_block_ == NULL) {
split_edge_merge_block_ = builder()->CreateBasicBlock(env->Copy());
builder()->GotoNoSimulate(first_false_block_, split_edge_merge_block_);
first_false_block_ = split_edge_merge_block_;
}
builder()->set_current_block(first_true_block_);
first_true_block_ = builder()->CreateBasicBlock(env->Copy());
}
void HGraphBuilder::IfBuilder::CaptureContinuation(
HIfContinuation* continuation) {
DCHECK(!did_else_if_);
DCHECK(!finished_);
DCHECK(!captured_);
HBasicBlock* true_block = NULL;
HBasicBlock* false_block = NULL;
Finish(&true_block, &false_block);
DCHECK(true_block != NULL);
DCHECK(false_block != NULL);
continuation->Capture(true_block, false_block);
captured_ = true;
builder()->set_current_block(NULL);
End();
}
void HGraphBuilder::IfBuilder::JoinContinuation(HIfContinuation* continuation) {
DCHECK(!did_else_if_);
DCHECK(!finished_);
DCHECK(!captured_);
HBasicBlock* true_block = NULL;
HBasicBlock* false_block = NULL;
Finish(&true_block, &false_block);
merge_at_join_blocks_ = NULL;
if (true_block != NULL && !true_block->IsFinished()) {
DCHECK(continuation->IsTrueReachable());
builder()->GotoNoSimulate(true_block, continuation->true_branch());
}
if (false_block != NULL && !false_block->IsFinished()) {
DCHECK(continuation->IsFalseReachable());
builder()->GotoNoSimulate(false_block, continuation->false_branch());
}
captured_ = true;
End();
}
void HGraphBuilder::IfBuilder::Then() {
DCHECK(!captured_);
DCHECK(!finished_);
did_then_ = true;
if (needs_compare_) {
// Handle if's without any expressions, they jump directly to the "else"
// branch. However, we must pretend that the "then" branch is reachable,
// so that the graph builder visits it and sees any live range extending
// constructs within it.
HConstant* constant_false = builder()->graph()->GetConstantFalse();
ToBooleanHints boolean_type = ToBooleanHint::kBoolean;
HBranch* branch = builder()->New<HBranch>(
constant_false, boolean_type, first_true_block_, first_false_block_);
builder()->FinishCurrentBlock(branch);
}
builder()->set_current_block(first_true_block_);
pending_merge_block_ = true;
}
void HGraphBuilder::IfBuilder::Else() {
DCHECK(did_then_);
DCHECK(!captured_);
DCHECK(!finished_);
AddMergeAtJoinBlock(false);
builder()->set_current_block(first_false_block_);
pending_merge_block_ = true;
did_else_ = true;
}
void HGraphBuilder::IfBuilder::Deopt(DeoptimizeReason reason) {
DCHECK(did_then_);
builder()->Add<HDeoptimize>(reason, Deoptimizer::EAGER);
AddMergeAtJoinBlock(true);
}
void HGraphBuilder::IfBuilder::Return(HValue* value) {
HValue* parameter_count = builder()->graph()->GetConstantMinus1();
builder()->FinishExitCurrentBlock(
builder()->New<HReturn>(value, parameter_count));
AddMergeAtJoinBlock(false);
}
void HGraphBuilder::IfBuilder::AddMergeAtJoinBlock(bool deopt) {
if (!pending_merge_block_) return;
HBasicBlock* block = builder()->current_block();
DCHECK(block == NULL || !block->IsFinished());
MergeAtJoinBlock* record = new (builder()->zone())
MergeAtJoinBlock(block, deopt, merge_at_join_blocks_);
merge_at_join_blocks_ = record;
if (block != NULL) {
DCHECK(block->end() == NULL);
if (deopt) {
normal_merge_at_join_block_count_++;
} else {
deopt_merge_at_join_block_count_++;
}
}
builder()->set_current_block(NULL);
pending_merge_block_ = false;
}
void HGraphBuilder::IfBuilder::Finish() {
DCHECK(!finished_);
if (!did_then_) {
Then();
}
AddMergeAtJoinBlock(false);
if (!did_else_) {
Else();
AddMergeAtJoinBlock(false);
}
finished_ = true;
}
void HGraphBuilder::IfBuilder::Finish(HBasicBlock** then_continuation,
HBasicBlock** else_continuation) {
Finish();
MergeAtJoinBlock* else_record = merge_at_join_blocks_;
if (else_continuation != NULL) {
*else_continuation = else_record->block_;
}
MergeAtJoinBlock* then_record = else_record->next_;
if (then_continuation != NULL) {
*then_continuation = then_record->block_;
}
DCHECK(then_record->next_ == NULL);
}
void HGraphBuilder::IfBuilder::EndUnreachable() {
if (captured_) return;
Finish();
builder()->set_current_block(nullptr);
}
void HGraphBuilder::IfBuilder::End() {
if (captured_) return;
Finish();
int total_merged_blocks = normal_merge_at_join_block_count_ +
deopt_merge_at_join_block_count_;
DCHECK(total_merged_blocks >= 1);
HBasicBlock* merge_block =
total_merged_blocks == 1 ? NULL : builder()->graph()->CreateBasicBlock();
// Merge non-deopt blocks first to ensure environment has right size for
// padding.
MergeAtJoinBlock* current = merge_at_join_blocks_;
while (current != NULL) {
if (!current->deopt_ && current->block_ != NULL) {
// If there is only one block that makes it through to the end of the
// if, then just set it as the current block and continue rather then
// creating an unnecessary merge block.
if (total_merged_blocks == 1) {
builder()->set_current_block(current->block_);
return;
}
builder()->GotoNoSimulate(current->block_, merge_block);
}
current = current->next_;
}
// Merge deopt blocks, padding when necessary.
current = merge_at_join_blocks_;
while (current != NULL) {
if (current->deopt_ && current->block_ != NULL) {
current->block_->FinishExit(
HAbnormalExit::New(builder()->isolate(), builder()->zone(), NULL),
SourcePosition::Unknown());
}
current = current->next_;
}
builder()->set_current_block(merge_block);
}
HGraphBuilder::LoopBuilder::LoopBuilder(HGraphBuilder* builder) {
Initialize(builder, NULL, kWhileTrue, NULL);
}
HGraphBuilder::LoopBuilder::LoopBuilder(HGraphBuilder* builder, HValue* context,
LoopBuilder::Direction direction) {
Initialize(builder, context, direction, builder->graph()->GetConstant1());
}
HGraphBuilder::LoopBuilder::LoopBuilder(HGraphBuilder* builder, HValue* context,
LoopBuilder::Direction direction,
HValue* increment_amount) {
Initialize(builder, context, direction, increment_amount);
increment_amount_ = increment_amount;
}
void HGraphBuilder::LoopBuilder::Initialize(HGraphBuilder* builder,
HValue* context,
Direction direction,
HValue* increment_amount) {
builder_ = builder;
context_ = context;
direction_ = direction;
increment_amount_ = increment_amount;
finished_ = false;
header_block_ = builder->CreateLoopHeaderBlock();
body_block_ = NULL;
exit_block_ = NULL;
exit_trampoline_block_ = NULL;
}
HValue* HGraphBuilder::LoopBuilder::BeginBody(
HValue* initial,
HValue* terminating,
Token::Value token) {
DCHECK(direction_ != kWhileTrue);
HEnvironment* env = builder_->environment();
phi_ = header_block_->AddNewPhi(env->values()->length());
phi_->AddInput(initial);
env->Push(initial);
builder_->GotoNoSimulate(header_block_);
HEnvironment* body_env = env->Copy();
HEnvironment* exit_env = env->Copy();
// Remove the phi from the expression stack
body_env->Pop();
exit_env->Pop();
body_block_ = builder_->CreateBasicBlock(body_env);
exit_block_ = builder_->CreateBasicBlock(exit_env);
builder_->set_current_block(header_block_);
env->Pop();
builder_->FinishCurrentBlock(builder_->New<HCompareNumericAndBranch>(
phi_, terminating, token, body_block_, exit_block_));
builder_->set_current_block(body_block_);
if (direction_ == kPreIncrement || direction_ == kPreDecrement) {
Isolate* isolate = builder_->isolate();
HValue* one = builder_->graph()->GetConstant1();
if (direction_ == kPreIncrement) {
increment_ = HAdd::New(isolate, zone(), context_, phi_, one);
} else {
increment_ = HSub::New(isolate, zone(), context_, phi_, one);
}
increment_->ClearFlag(HValue::kCanOverflow);
builder_->AddInstruction(increment_);
return increment_;
} else {
return phi_;
}
}
void HGraphBuilder::LoopBuilder::BeginBody(int drop_count) {
DCHECK(direction_ == kWhileTrue);
HEnvironment* env = builder_->environment();
builder_->GotoNoSimulate(header_block_);
builder_->set_current_block(header_block_);
env->Drop(drop_count);
}
void HGraphBuilder::LoopBuilder::Break() {
if (exit_trampoline_block_ == NULL) {
// Its the first time we saw a break.
if (direction_ == kWhileTrue) {
HEnvironment* env = builder_->environment()->Copy();
exit_trampoline_block_ = builder_->CreateBasicBlock(env);
} else {
HEnvironment* env = exit_block_->last_environment()->Copy();
exit_trampoline_block_ = builder_->CreateBasicBlock(env);
builder_->GotoNoSimulate(exit_block_, exit_trampoline_block_);
}
}
builder_->GotoNoSimulate(exit_trampoline_block_);
builder_->set_current_block(NULL);
}
void HGraphBuilder::LoopBuilder::EndBody() {
DCHECK(!finished_);
if (direction_ == kPostIncrement || direction_ == kPostDecrement) {
Isolate* isolate = builder_->isolate();
if (direction_ == kPostIncrement) {
increment_ =
HAdd::New(isolate, zone(), context_, phi_, increment_amount_);
} else {
increment_ =
HSub::New(isolate, zone(), context_, phi_, increment_amount_);
}
increment_->ClearFlag(HValue::kCanOverflow);
builder_->AddInstruction(increment_);
}
if (direction_ != kWhileTrue) {
// Push the new increment value on the expression stack to merge into
// the phi.
builder_->environment()->Push(increment_);
}
HBasicBlock* last_block = builder_->current_block();
builder_->GotoNoSimulate(last_block, header_block_);
header_block_->loop_information()->RegisterBackEdge(last_block);
if (exit_trampoline_block_ != NULL) {
builder_->set_current_block(exit_trampoline_block_);
} else {
builder_->set_current_block(exit_block_);
}
finished_ = true;
}
HGraph* HGraphBuilder::CreateGraph() {
DCHECK(!FLAG_minimal);
graph_ = new (zone()) HGraph(info_, descriptor_);
if (FLAG_hydrogen_stats) isolate()->GetHStatistics()->Initialize(info_);
CompilationPhase phase("H_Block building", info_);
set_current_block(graph()->entry_block());
if (!BuildGraph()) return NULL;
graph()->FinalizeUniqueness();
return graph_;
}
HInstruction* HGraphBuilder::AddInstruction(HInstruction* instr) {
DCHECK(current_block() != NULL);
DCHECK(!FLAG_hydrogen_track_positions || position_.IsKnown() ||
!info_->IsOptimizing());
current_block()->AddInstruction(instr, source_position());
if (graph()->IsInsideNoSideEffectsScope()) {
instr->SetFlag(HValue::kHasNoObservableSideEffects);
}
return instr;
}
void HGraphBuilder::FinishCurrentBlock(HControlInstruction* last) {
DCHECK(!FLAG_hydrogen_track_positions || !info_->IsOptimizing() ||
position_.IsKnown());
current_block()->Finish(last, source_position());
if (last->IsReturn() || last->IsAbnormalExit()) {
set_current_block(NULL);
}
}
void HGraphBuilder::FinishExitCurrentBlock(HControlInstruction* instruction) {
DCHECK(!FLAG_hydrogen_track_positions || !info_->IsOptimizing() ||
position_.IsKnown());
current_block()->FinishExit(instruction, source_position());
if (instruction->IsReturn() || instruction->IsAbnormalExit()) {
set_current_block(NULL);
}
}
void HGraphBuilder::AddIncrementCounter(StatsCounter* counter) {
if (FLAG_native_code_counters && counter->Enabled()) {
HValue* reference = Add<HConstant>(ExternalReference(counter));
HValue* old_value =
Add<HLoadNamedField>(reference, nullptr, HObjectAccess::ForCounter());
HValue* new_value = AddUncasted<HAdd>(old_value, graph()->GetConstant1());
new_value->ClearFlag(HValue::kCanOverflow); // Ignore counter overflow
Add<HStoreNamedField>(reference, HObjectAccess::ForCounter(),
new_value, STORE_TO_INITIALIZED_ENTRY);
}
}
void HGraphBuilder::AddSimulate(BailoutId id,
RemovableSimulate removable) {
DCHECK(current_block() != NULL);
DCHECK(!graph()->IsInsideNoSideEffectsScope());
current_block()->AddNewSimulate(id, source_position(), removable);
}
HBasicBlock* HGraphBuilder::CreateBasicBlock(HEnvironment* env) {
HBasicBlock* b = graph()->CreateBasicBlock();
b->SetInitialEnvironment(env);
return b;
}
HBasicBlock* HGraphBuilder::CreateLoopHeaderBlock() {
HBasicBlock* header = graph()->CreateBasicBlock();
HEnvironment* entry_env = environment()->CopyAsLoopHeader(header);
header->SetInitialEnvironment(entry_env);
header->AttachLoopInformation();
return header;
}
HValue* HGraphBuilder::BuildGetElementsKind(HValue* object) {
HValue* map = Add<HLoadNamedField>(object, nullptr, HObjectAccess::ForMap());
HValue* bit_field2 =
Add<HLoadNamedField>(map, nullptr, HObjectAccess::ForMapBitField2());
return BuildDecodeField<Map::ElementsKindBits>(bit_field2);
}
HValue* HGraphBuilder::BuildEnumLength(HValue* map) {
NoObservableSideEffectsScope scope(this);
HValue* bit_field3 =
Add<HLoadNamedField>(map, nullptr, HObjectAccess::ForMapBitField3());
return BuildDecodeField<Map::EnumLengthBits>(bit_field3);
}
HValue* HGraphBuilder::BuildCheckHeapObject(HValue* obj) {
if (obj->type().IsHeapObject()) return obj;
return Add<HCheckHeapObject>(obj);
}
void HGraphBuilder::FinishExitWithHardDeoptimization(DeoptimizeReason reason) {
Add<HDeoptimize>(reason, Deoptimizer::EAGER);
FinishExitCurrentBlock(New<HAbnormalExit>());
}
HValue* HGraphBuilder::BuildCheckString(HValue* string) {
if (!string->type().IsString()) {
DCHECK(!string->IsConstant() ||
!HConstant::cast(string)->HasStringValue());
BuildCheckHeapObject(string);
return Add<HCheckInstanceType>(string, HCheckInstanceType::IS_STRING);
}
return string;
}
HValue* HGraphBuilder::BuildWrapReceiver(HValue* object, HValue* checked) {
if (object->type().IsJSObject()) return object;
HValue* function = checked->ActualValue();
if (function->IsConstant() &&
HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
Handle<JSFunction> f = Handle<JSFunction>::cast(
HConstant::cast(function)->handle(isolate()));
SharedFunctionInfo* shared = f->shared();
if (is_strict(shared->language_mode()) || shared->native()) return object;
}
return Add<HWrapReceiver>(object, checked);
}
HValue* HGraphBuilder::BuildCheckAndGrowElementsCapacity(
HValue* object, HValue* elements, ElementsKind kind, HValue* length,
HValue* capacity, HValue* key) {
HValue* max_gap = Add<HConstant>(static_cast<int32_t>(JSObject::kMaxGap));
HValue* max_capacity = AddUncasted<HAdd>(capacity, max_gap);
Add<HBoundsCheck>(key, max_capacity);
HValue* new_capacity = BuildNewElementsCapacity(key);
HValue* new_elements = BuildGrowElementsCapacity(object, elements, kind, kind,
length, new_capacity);
return new_elements;
}
HValue* HGraphBuilder::BuildCheckForCapacityGrow(
HValue* object,
HValue* elements,
ElementsKind kind,
HValue* length,
HValue* key,
bool is_js_array,
PropertyAccessType access_type) {
IfBuilder length_checker(this);
Token::Value token = IsHoleyElementsKind(kind) ? Token::GTE : Token::EQ;
length_checker.If<HCompareNumericAndBranch>(key, length, token);
length_checker.Then();
HValue* current_capacity = AddLoadFixedArrayLength(elements);
if (top_info()->IsStub()) {
IfBuilder capacity_checker(this);
capacity_checker.If<HCompareNumericAndBranch>(key, current_capacity,
Token::GTE);
capacity_checker.Then();
HValue* new_elements = BuildCheckAndGrowElementsCapacity(
object, elements, kind, length, current_capacity, key);
environment()->Push(new_elements);
capacity_checker.Else();
environment()->Push(elements);
capacity_checker.End();
} else {
HValue* result = Add<HMaybeGrowElements>(
object, elements, key, current_capacity, is_js_array, kind);
environment()->Push(result);
}
if (is_js_array) {
HValue* new_length = AddUncasted<HAdd>(key, graph_->GetConstant1());
new_length->ClearFlag(HValue::kCanOverflow);
Add<HStoreNamedField>(object, HObjectAccess::ForArrayLength(kind),
new_length);
}
if (access_type == STORE && kind == FAST_SMI_ELEMENTS) {
HValue* checked_elements = environment()->Top();
// Write zero to ensure that the new element is initialized with some smi.
Add<HStoreKeyed>(checked_elements, key, graph()->GetConstant0(), nullptr,
kind);
}
length_checker.Else();
Add<HBoundsCheck>(key, length);
environment()->Push(elements);
length_checker.End();
return environment()->Pop();
}
HValue* HGraphBuilder::BuildCopyElementsOnWrite(HValue* object,
HValue* elements,
ElementsKind kind,
HValue* length) {
Factory* factory = isolate()->factory();
IfBuilder cow_checker(this);
cow_checker.If<HCompareMap>(elements, factory->fixed_cow_array_map());
cow_checker.Then();
HValue* capacity = AddLoadFixedArrayLength(elements);
HValue* new_elements = BuildGrowElementsCapacity(object, elements, kind,
kind, length, capacity);
environment()->Push(new_elements);
cow_checker.Else();
environment()->Push(elements);
cow_checker.End();
return environment()->Pop();
}
HValue* HGraphBuilder::BuildCreateIterResultObject(HValue* value,
HValue* done) {
NoObservableSideEffectsScope scope(this);
// Allocate the JSIteratorResult object.
HValue* result =
Add<HAllocate>(Add<HConstant>(JSIteratorResult::kSize), HType::JSObject(),
NOT_TENURED, JS_OBJECT_TYPE, graph()->GetConstant0());
// Initialize the JSIteratorResult object.
HValue* native_context = BuildGetNativeContext();
HValue* map = Add<HLoadNamedField>(
native_context, nullptr,
HObjectAccess::ForContextSlot(Context::ITERATOR_RESULT_MAP_INDEX));
Add<HStoreNamedField>(result, HObjectAccess::ForMap(), map);
HValue* empty_fixed_array = Add<HLoadRoot>(Heap::kEmptyFixedArrayRootIndex);
Add<HStoreNamedField>(result, HObjectAccess::ForPropertiesPointer(),
empty_fixed_array);
Add<HStoreNamedField>(result, HObjectAccess::ForElementsPointer(),
empty_fixed_array);
Add<HStoreNamedField>(result, HObjectAccess::ForObservableJSObjectOffset(
JSIteratorResult::kValueOffset),
value);
Add<HStoreNamedField>(result, HObjectAccess::ForObservableJSObjectOffset(
JSIteratorResult::kDoneOffset),
done);
STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
return result;
}
HValue* HGraphBuilder::BuildNumberToString(HValue* object, AstType* type) {
NoObservableSideEffectsScope scope(this);
// Convert constant numbers at compile time.
if (object->IsConstant() && HConstant::cast(object)->HasNumberValue()) {
Handle<Object> number = HConstant::cast(object)->handle(isolate());
Handle<String> result = isolate()->factory()->NumberToString(number);
return Add<HConstant>(result);
}
// Create a joinable continuation.
HIfContinuation found(graph()->CreateBasicBlock(),
graph()->CreateBasicBlock());
// Load the number string cache.
HValue* number_string_cache =
Add<HLoadRoot>(Heap::kNumberStringCacheRootIndex);
// Make the hash mask from the length of the number string cache. It
// contains two elements (number and string) for each cache entry.
HValue* mask = AddLoadFixedArrayLength(number_string_cache);
mask->set_type(HType::Smi());
mask = AddUncasted<HSar>(mask, graph()->GetConstant1());
mask = AddUncasted<HSub>(mask, graph()->GetConstant1());
// Check whether object is a smi.
IfBuilder if_objectissmi(this);
if_objectissmi.If<HIsSmiAndBranch>(object);
if_objectissmi.Then();
{
// Compute hash for smi similar to smi_get_hash().
HValue* hash = AddUncasted<HBitwise>(Token::BIT_AND, object, mask);
// Load the key.
HValue* key_index = AddUncasted<HShl>(hash, graph()->GetConstant1());
HValue* key = Add<HLoadKeyed>(number_string_cache, key_index, nullptr,
nullptr, FAST_ELEMENTS, ALLOW_RETURN_HOLE);
// Check if object == key.
IfBuilder if_objectiskey(this);
if_objectiskey.If<HCompareObjectEqAndBranch>(object, key);
if_objectiskey.Then();
{
// Make the key_index available.
Push(key_index);
}
if_objectiskey.JoinContinuation(&found);
}
if_objectissmi.Else();
{
if (type->Is(AstType::SignedSmall())) {
if_objectissmi.Deopt(DeoptimizeReason::kExpectedSmi);
} else {
// Check if the object is a heap number.
IfBuilder if_objectisnumber(this);
HValue* objectisnumber = if_objectisnumber.If<HCompareMap>(
object, isolate()->factory()->heap_number_map());
if_objectisnumber.Then();
{
// Compute hash for heap number similar to double_get_hash().
HValue* low = Add<HLoadNamedField>(
object, objectisnumber,
HObjectAccess::ForHeapNumberValueLowestBits());
HValue* high = Add<HLoadNamedField>(
object, objectisnumber,
HObjectAccess::ForHeapNumberValueHighestBits());
HValue* hash = AddUncasted<HBitwise>(Token::BIT_XOR, low, high);
hash = AddUncasted<HBitwise>(Token::BIT_AND, hash, mask);
// Load the key.
HValue* key_index = AddUncasted<HShl>(hash, graph()->GetConstant1());
HValue* key =
Add<HLoadKeyed>(number_string_cache, key_index, nullptr, nullptr,
FAST_ELEMENTS, ALLOW_RETURN_HOLE);
// Check if the key is a heap number and compare it with the object.
IfBuilder if_keyisnotsmi(this);
HValue* keyisnotsmi = if_keyisnotsmi.IfNot<HIsSmiAndBranch>(key);
if_keyisnotsmi.Then();
{
IfBuilder if_keyisheapnumber(this);
if_keyisheapnumber.If<HCompareMap>(
key, isolate()->factory()->heap_number_map());
if_keyisheapnumber.Then();
{
// Check if values of key and object match.
IfBuilder if_keyeqobject(this);
if_keyeqobject.If<HCompareNumericAndBranch>(
Add<HLoadNamedField>(key, keyisnotsmi,
HObjectAccess::ForHeapNumberValue()),
Add<HLoadNamedField>(object, objectisnumber,
HObjectAccess::ForHeapNumberValue()),
Token::EQ);
if_keyeqobject.Then();
{
// Make the key_index available.
Push(key_index);
}
if_keyeqobject.JoinContinuation(&found);
}
if_keyisheapnumber.JoinContinuation(&found);
}
if_keyisnotsmi.JoinContinuation(&found);
}
if_objectisnumber.Else();
{
if (type->Is(AstType::Number())) {
if_objectisnumber.Deopt(DeoptimizeReason::kExpectedHeapNumber);
}
}
if_objectisnumber.JoinContinuation(&found);
}
}
if_objectissmi.JoinContinuation(&found);
// Check for cache hit.
IfBuilder if_found(this, &found);
if_found.Then();
{
// Count number to string operation in native code.
AddIncrementCounter(isolate()->counters()->number_to_string_native());
// Load the value in case of cache hit.
HValue* key_index = Pop();
HValue* value_index = AddUncasted<HAdd>(key_index, graph()->GetConstant1());
Push(Add<HLoadKeyed>(number_string_cache, value_index, nullptr, nullptr,
FAST_ELEMENTS, ALLOW_RETURN_HOLE));
}
if_found.Else();
{
// Cache miss, fallback to runtime.
Add<HPushArguments>(object);
Push(Add<HCallRuntime>(
Runtime::FunctionForId(Runtime::kNumberToStringSkipCache),
1));
}
if_found.End();
return Pop();
}
HValue* HGraphBuilder::BuildToNumber(HValue* input) {
if (input->type().IsTaggedNumber() ||
input->representation().IsSpecialization()) {
return input;
}
Callable callable = CodeFactory::ToNumber(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {input};
HCallWithDescriptor* instr = Add<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
instr->set_type(HType::TaggedNumber());
return instr;
}
HValue* HGraphBuilder::BuildToObject(HValue* receiver) {
NoObservableSideEffectsScope scope(this);
// Create a joinable continuation.
HIfContinuation wrap(graph()->CreateBasicBlock(),
graph()->CreateBasicBlock());
// Determine the proper global constructor function required to wrap
// {receiver} into a JSValue, unless {receiver} is already a {JSReceiver}, in
// which case we just return it. Deopts to Runtime::kToObject if {receiver}
// is undefined or null.
IfBuilder receiver_is_smi(this);
receiver_is_smi.If<HIsSmiAndBranch>(receiver);
receiver_is_smi.Then();
{
// Use global Number function.
Push(Add<HConstant>(Context::NUMBER_FUNCTION_INDEX));
}
receiver_is_smi.Else();
{
// Determine {receiver} map and instance type.
HValue* receiver_map =
Add<HLoadNamedField>(receiver, nullptr, HObjectAccess::ForMap());
HValue* receiver_instance_type = Add<HLoadNamedField>(
receiver_map, nullptr, HObjectAccess::ForMapInstanceType());
// First check whether {receiver} is already a spec object (fast case).
IfBuilder receiver_is_not_spec_object(this);
receiver_is_not_spec_object.If<HCompareNumericAndBranch>(
receiver_instance_type, Add<HConstant>(FIRST_JS_RECEIVER_TYPE),
Token::LT);
receiver_is_not_spec_object.Then();
{
// Load the constructor function index from the {receiver} map.
HValue* constructor_function_index = Add<HLoadNamedField>(
receiver_map, nullptr,
HObjectAccess::ForMapInObjectPropertiesOrConstructorFunctionIndex());
// Check if {receiver} has a constructor (null and undefined have no
// constructors, so we deoptimize to the runtime to throw an exception).
IfBuilder constructor_function_index_is_invalid(this);
constructor_function_index_is_invalid.If<HCompareNumericAndBranch>(
constructor_function_index,
Add<HConstant>(Map::kNoConstructorFunctionIndex), Token::EQ);
constructor_function_index_is_invalid.ThenDeopt(
DeoptimizeReason::kUndefinedOrNullInToObject);
constructor_function_index_is_invalid.End();
// Use the global constructor function.
Push(constructor_function_index);
}
receiver_is_not_spec_object.JoinContinuation(&wrap);
}
receiver_is_smi.JoinContinuation(&wrap);
// Wrap the receiver if necessary.
IfBuilder if_wrap(this, &wrap);
if_wrap.Then();
{
// Grab the constructor function index.
HValue* constructor_index = Pop();
// Load native context.
HValue* native_context = BuildGetNativeContext();
// Determine the initial map for the global constructor.
HValue* constructor = Add<HLoadKeyed>(native_context, constructor_index,
nullptr, nullptr, FAST_ELEMENTS);
HValue* constructor_initial_map = Add<HLoadNamedField>(
constructor, nullptr, HObjectAccess::ForPrototypeOrInitialMap());
// Allocate and initialize a JSValue wrapper.
HValue* value =
BuildAllocate(Add<HConstant>(JSValue::kSize), HType::JSObject(),
JS_VALUE_TYPE, HAllocationMode());
Add<HStoreNamedField>(value, HObjectAccess::ForMap(),
constructor_initial_map);
HValue* empty_fixed_array = Add<HLoadRoot>(Heap::kEmptyFixedArrayRootIndex);
Add<HStoreNamedField>(value, HObjectAccess::ForPropertiesPointer(),
empty_fixed_array);
Add<HStoreNamedField>(value, HObjectAccess::ForElementsPointer(),
empty_fixed_array);
Add<HStoreNamedField>(value, HObjectAccess::ForObservableJSObjectOffset(
JSValue::kValueOffset),
receiver);
Push(value);
}
if_wrap.Else();
{ Push(receiver); }
if_wrap.End();
return Pop();
}
HAllocate* HGraphBuilder::BuildAllocate(
HValue* object_size,
HType type,
InstanceType instance_type,
HAllocationMode allocation_mode) {
// Compute the effective allocation size.
HValue* size = object_size;
if (allocation_mode.CreateAllocationMementos()) {
size = AddUncasted<HAdd>(size, Add<HConstant>(AllocationMemento::kSize));
size->ClearFlag(HValue::kCanOverflow);
}
// Perform the actual allocation.
HAllocate* object = Add<HAllocate>(
size, type, allocation_mode.GetPretenureMode(), instance_type,
graph()->GetConstant0(), allocation_mode.feedback_site());
// Setup the allocation memento.
if (allocation_mode.CreateAllocationMementos()) {
BuildCreateAllocationMemento(
object, object_size, allocation_mode.current_site());
}
return object;
}
HValue* HGraphBuilder::BuildAddStringLengths(HValue* left_length,
HValue* right_length) {
// Compute the combined string length and check against max string length.
HValue* length = AddUncasted<HAdd>(left_length, right_length);
// Check that length <= kMaxLength <=> length < MaxLength + 1.
HValue* max_length = Add<HConstant>(String::kMaxLength + 1);
if (top_info()->IsStub() || !isolate()->IsStringLengthOverflowIntact()) {
// This is a mitigation for crbug.com/627934; the real fix
// will be to migrate the StringAddStub to TurboFan one day.
IfBuilder if_invalid(this);
if_invalid.If<HCompareNumericAndBranch>(length, max_length, Token::GT);
if_invalid.Then();
{
Add<HCallRuntime>(
Runtime::FunctionForId(Runtime::kThrowInvalidStringLength), 0);
}
if_invalid.End();
} else {
graph()->MarkDependsOnStringLengthOverflow();
Add<HBoundsCheck>(length, max_length);
}
return length;
}
HValue* HGraphBuilder::BuildCreateConsString(
HValue* length,
HValue* left,
HValue* right,
HAllocationMode allocation_mode) {
// Determine the string instance types.
HInstruction* left_instance_type = AddLoadStringInstanceType(left);
HInstruction* right_instance_type = AddLoadStringInstanceType(right);
// Allocate the cons string object. HAllocate does not care whether we
// pass CONS_STRING_TYPE or CONS_ONE_BYTE_STRING_TYPE here, so we just use
// CONS_STRING_TYPE here. Below we decide whether the cons string is
// one-byte or two-byte and set the appropriate map.
DCHECK(HAllocate::CompatibleInstanceTypes(CONS_STRING_TYPE,
CONS_ONE_BYTE_STRING_TYPE));
HAllocate* result = BuildAllocate(Add<HConstant>(ConsString::kSize),
HType::String(), CONS_STRING_TYPE,
allocation_mode);
// Compute intersection and difference of instance types.
HValue* anded_instance_types = AddUncasted<HBitwise>(
Token::BIT_AND, left_instance_type, right_instance_type);
HValue* xored_instance_types = AddUncasted<HBitwise>(
Token::BIT_XOR, left_instance_type, right_instance_type);
// We create a one-byte cons string if
// 1. both strings are one-byte, or
// 2. at least one of the strings is two-byte, but happens to contain only
// one-byte characters.
// To do this, we check
// 1. if both strings are one-byte, or if the one-byte data hint is set in
// both strings, or
// 2. if one of the strings has the one-byte data hint set and the other
// string is one-byte.
IfBuilder if_onebyte(this);
STATIC_ASSERT(kOneByteStringTag != 0);
STATIC_ASSERT(kOneByteDataHintMask != 0);
if_onebyte.If<HCompareNumericAndBranch>(
AddUncasted<HBitwise>(
Token::BIT_AND, anded_instance_types,
Add<HConstant>(static_cast<int32_t>(
kStringEncodingMask | kOneByteDataHintMask))),
graph()->GetConstant0(), Token::NE);
if_onebyte.Or();
STATIC_ASSERT(kOneByteStringTag != 0 &&
kOneByteDataHintTag != 0 &&
kOneByteDataHintTag != kOneByteStringTag);
if_onebyte.If<HCompareNumericAndBranch>(
AddUncasted<HBitwise>(
Token::BIT_AND, xored_instance_types,
Add<HConstant>(static_cast<int32_t>(
kOneByteStringTag | kOneByteDataHintTag))),
Add<HConstant>(static_cast<int32_t>(
kOneByteStringTag | kOneByteDataHintTag)), Token::EQ);
if_onebyte.Then();
{
// We can safely skip the write barrier for storing the map here.
Add<HStoreNamedField>(
result, HObjectAccess::ForMap(),
Add<HConstant>(isolate()->factory()->cons_one_byte_string_map()));
}
if_onebyte.Else();
{
// We can safely skip the write barrier for storing the map here.
Add<HStoreNamedField>(
result, HObjectAccess::ForMap(),
Add<HConstant>(isolate()->factory()->cons_string_map()));
}
if_onebyte.End();
// Initialize the cons string fields.
Add<HStoreNamedField>(result, HObjectAccess::ForStringHashField(),
Add<HConstant>(String::kEmptyHashField));
Add<HStoreNamedField>(result, HObjectAccess::ForStringLength(), length);
Add<HStoreNamedField>(result, HObjectAccess::ForConsStringFirst(), left);
Add<HStoreNamedField>(result, HObjectAccess::ForConsStringSecond(), right);
// Count the native string addition.
AddIncrementCounter(isolate()->counters()->string_add_native());
return result;
}
void HGraphBuilder::BuildCopySeqStringChars(HValue* src,
HValue* src_offset,
String::Encoding src_encoding,
HValue* dst,
HValue* dst_offset,
String::Encoding dst_encoding,
HValue* length) {
DCHECK(dst_encoding != String::ONE_BYTE_ENCODING ||
src_encoding == String::ONE_BYTE_ENCODING);
LoopBuilder loop(this, context(), LoopBuilder::kPostIncrement);
HValue* index = loop.BeginBody(graph()->GetConstant0(), length, Token::LT);
{
HValue* src_index = AddUncasted<HAdd>(src_offset, index);
HValue* value =
AddUncasted<HSeqStringGetChar>(src_encoding, src, src_index);
HValue* dst_index = AddUncasted<HAdd>(dst_offset, index);
Add<HSeqStringSetChar>(dst_encoding, dst, dst_index, value);
}
loop.EndBody();
}
HValue* HGraphBuilder::BuildObjectSizeAlignment(
HValue* unaligned_size, int header_size) {
DCHECK((header_size & kObjectAlignmentMask) == 0);
HValue* size = AddUncasted<HAdd>(
unaligned_size, Add<HConstant>(static_cast<int32_t>(
header_size + kObjectAlignmentMask)));
size->ClearFlag(HValue::kCanOverflow);
return AddUncasted<HBitwise>(
Token::BIT_AND, size, Add<HConstant>(static_cast<int32_t>(
~kObjectAlignmentMask)));
}
HValue* HGraphBuilder::BuildUncheckedStringAdd(
HValue* left,
HValue* right,
HAllocationMode allocation_mode) {
// Determine the string lengths.
HValue* left_length = AddLoadStringLength(left);
HValue* right_length = AddLoadStringLength(right);
// Compute the combined string length.
HValue* length = BuildAddStringLengths(left_length, right_length);
// Do some manual constant folding here.
if (left_length->IsConstant()) {
HConstant* c_left_length = HConstant::cast(left_length);
DCHECK_NE(0, c_left_length->Integer32Value());
if (c_left_length->Integer32Value() + 1 >= ConsString::kMinLength) {
// The right string contains at least one character.
return BuildCreateConsString(length, left, right, allocation_mode);
}
} else if (right_length->IsConstant()) {
HConstant* c_right_length = HConstant::cast(right_length);
DCHECK_NE(0, c_right_length->Integer32Value());
if (c_right_length->Integer32Value() + 1 >= ConsString::kMinLength) {
// The left string contains at least one character.
return BuildCreateConsString(length, left, right, allocation_mode);
}
}
// Check if we should create a cons string.
IfBuilder if_createcons(this);
if_createcons.If<HCompareNumericAndBranch>(
length, Add<HConstant>(ConsString::kMinLength), Token::GTE);
if_createcons.And();
if_createcons.If<HCompareNumericAndBranch>(
length, Add<HConstant>(ConsString::kMaxLength), Token::LTE);
if_createcons.Then();
{
// Create a cons string.
Push(BuildCreateConsString(length, left, right, allocation_mode));
}
if_createcons.Else();
{
// Determine the string instance types.
HValue* left_instance_type = AddLoadStringInstanceType(left);
HValue* right_instance_type = AddLoadStringInstanceType(right);
// Compute union and difference of instance types.
HValue* ored_instance_types = AddUncasted<HBitwise>(
Token::BIT_OR, left_instance_type, right_instance_type);
HValue* xored_instance_types = AddUncasted<HBitwise>(
Token::BIT_XOR, left_instance_type, right_instance_type);
// Check if both strings have the same encoding and both are
// sequential.
IfBuilder if_sameencodingandsequential(this);
if_sameencodingandsequential.If<HCompareNumericAndBranch>(
AddUncasted<HBitwise>(
Token::BIT_AND, xored_instance_types,
Add<HConstant>(static_cast<int32_t>(kStringEncodingMask))),
graph()->GetConstant0(), Token::EQ);
if_sameencodingandsequential.And();
STATIC_ASSERT(kSeqStringTag == 0);
if_sameencodingandsequential.If<HCompareNumericAndBranch>(
AddUncasted<HBitwise>(
Token::BIT_AND, ored_instance_types,
Add<HConstant>(static_cast<int32_t>(kStringRepresentationMask))),
graph()->GetConstant0(), Token::EQ);
if_sameencodingandsequential.Then();
{
HConstant* string_map =
Add<HConstant>(isolate()->factory()->string_map());
HConstant* one_byte_string_map =
Add<HConstant>(isolate()->factory()->one_byte_string_map());
// Determine map and size depending on whether result is one-byte string.
IfBuilder if_onebyte(this);
STATIC_ASSERT(kOneByteStringTag != 0);
if_onebyte.If<HCompareNumericAndBranch>(
AddUncasted<HBitwise>(
Token::BIT_AND, ored_instance_types,
Add<HConstant>(static_cast<int32_t>(kStringEncodingMask))),
graph()->GetConstant0(), Token::NE);
if_onebyte.Then();
{
// Allocate sequential one-byte string object.
Push(length);
Push(one_byte_string_map);
}
if_onebyte.Else();
{
// Allocate sequential two-byte string object.
HValue* size = AddUncasted<HShl>(length, graph()->GetConstant1());
size->ClearFlag(HValue::kCanOverflow);
size->SetFlag(HValue::kUint32);
Push(size);
Push(string_map);
}
if_onebyte.End();
HValue* map = Pop();
// Calculate the number of bytes needed for the characters in the
// string while observing object alignment.
STATIC_ASSERT((SeqString::kHeaderSize & kObjectAlignmentMask) == 0);
HValue* size = BuildObjectSizeAlignment(Pop(), SeqString::kHeaderSize);
IfBuilder if_size(this);
if_size.If<HCompareNumericAndBranch>(
size, Add<HConstant>(kMaxRegularHeapObjectSize), Token::LT);
if_size.Then();
{
// Allocate the string object. HAllocate does not care whether we pass
// STRING_TYPE or ONE_BYTE_STRING_TYPE here, so we just use STRING_TYPE.
HAllocate* result =
BuildAllocate(size, HType::String(), STRING_TYPE, allocation_mode);
Add<HStoreNamedField>(result, HObjectAccess::ForMap(), map);
// Initialize the string fields.
Add<HStoreNamedField>(result, HObjectAccess::ForStringHashField(),
Add<HConstant>(String::kEmptyHashField));
Add<HStoreNamedField>(result, HObjectAccess::ForStringLength(), length);
// Copy characters to the result string.
IfBuilder if_twobyte(this);
if_twobyte.If<HCompareObjectEqAndBranch>(map, string_map);
if_twobyte.Then();
{
// Copy characters from the left string.
BuildCopySeqStringChars(
left, graph()->GetConstant0(), String::TWO_BYTE_ENCODING, result,
graph()->GetConstant0(), String::TWO_BYTE_ENCODING, left_length);
// Copy characters from the right string.
BuildCopySeqStringChars(
right, graph()->GetConstant0(), String::TWO_BYTE_ENCODING, result,
left_length, String::TWO_BYTE_ENCODING, right_length);
}
if_twobyte.Else();
{
// Copy characters from the left string.
BuildCopySeqStringChars(
left, graph()->GetConstant0(), String::ONE_BYTE_ENCODING, result,
graph()->GetConstant0(), String::ONE_BYTE_ENCODING, left_length);
// Copy characters from the right string.
BuildCopySeqStringChars(
right, graph()->GetConstant0(), String::ONE_BYTE_ENCODING, result,
left_length, String::ONE_BYTE_ENCODING, right_length);
}
if_twobyte.End();
// Count the native string addition.
AddIncrementCounter(isolate()->counters()->string_add_native());
// Return the sequential string.
Push(result);
}
if_size.Else();
{
// Fallback to the runtime to add the two strings. The string has to be
// allocated in LO space.
Add<HPushArguments>(left, right);
Push(Add<HCallRuntime>(Runtime::FunctionForId(Runtime::kStringAdd), 2));
}
if_size.End();
}
if_sameencodingandsequential.Else();
{
// Fallback to the runtime to add the two strings.
Add<HPushArguments>(left, right);
Push(Add<HCallRuntime>(Runtime::FunctionForId(Runtime::kStringAdd), 2));
}
if_sameencodingandsequential.End();
}
if_createcons.End();
return Pop();
}
HValue* HGraphBuilder::BuildStringAdd(
HValue* left,
HValue* right,
HAllocationMode allocation_mode) {
NoObservableSideEffectsScope no_effects(this);
// Determine string lengths.
HValue* left_length = AddLoadStringLength(left);
HValue* right_length = AddLoadStringLength(right);
// Check if left string is empty.
IfBuilder if_leftempty(this);
if_leftempty.If<HCompareNumericAndBranch>(
left_length, graph()->GetConstant0(), Token::EQ);
if_leftempty.Then();
{
// Count the native string addition.
AddIncrementCounter(isolate()->counters()->string_add_native());
// Just return the right string.
Push(right);
}
if_leftempty.Else();
{
// Check if right string is empty.
IfBuilder if_rightempty(this);
if_rightempty.If<HCompareNumericAndBranch>(
right_length, graph()->GetConstant0(), Token::EQ);
if_rightempty.Then();
{
// Count the native string addition.
AddIncrementCounter(isolate()->counters()->string_add_native());
// Just return the left string.
Push(left);
}
if_rightempty.Else();
{
// Add the two non-empty strings.
Push(BuildUncheckedStringAdd(left, right, allocation_mode));
}
if_rightempty.End();
}
if_leftempty.End();
return Pop();
}
HInstruction* HGraphBuilder::BuildUncheckedMonomorphicElementAccess(
HValue* checked_object,
HValue* key,
HValue* val,
bool is_js_array,
ElementsKind elements_kind,
PropertyAccessType access_type,
LoadKeyedHoleMode load_mode,
KeyedAccessStoreMode store_mode) {
DCHECK(top_info()->IsStub() || checked_object->IsCompareMap() ||
checked_object->IsCheckMaps());
DCHECK(!IsFixedTypedArrayElementsKind(elements_kind) || !is_js_array);
// No GVNFlag is necessary for ElementsKind if there is an explicit dependency
// on a HElementsTransition instruction. The flag can also be removed if the
// map to check has FAST_HOLEY_ELEMENTS, since there can be no further
// ElementsKind transitions. Finally, the dependency can be removed for stores
// for FAST_ELEMENTS, since a transition to HOLEY elements won't change the
// generated store code.
if ((elements_kind == FAST_HOLEY_ELEMENTS) ||
(elements_kind == FAST_ELEMENTS && access_type == STORE)) {
checked_object->ClearDependsOnFlag(kElementsKind);
}
bool fast_smi_only_elements = IsFastSmiElementsKind(elements_kind);
bool fast_elements = IsFastObjectElementsKind(elements_kind);
HValue* elements = AddLoadElements(checked_object);
if (access_type == STORE && (fast_elements || fast_smi_only_elements) &&
store_mode != STORE_NO_TRANSITION_HANDLE_COW) {
HCheckMaps* check_cow_map = Add<HCheckMaps>(
elements, isolate()->factory()->fixed_array_map());
check_cow_map->ClearDependsOnFlag(kElementsKind);
}
HInstruction* length = NULL;
if (is_js_array) {
length = Add<HLoadNamedField>(
checked_object->ActualValue(), checked_object,
HObjectAccess::ForArrayLength(elements_kind));
} else {
length = AddLoadFixedArrayLength(elements);
}
length->set_type(HType::Smi());
HValue* checked_key = NULL;
if (IsFixedTypedArrayElementsKind(elements_kind)) {
checked_object = Add<HCheckArrayBufferNotNeutered>(checked_object);
HValue* external_pointer = Add<HLoadNamedField>(
elements, nullptr,
HObjectAccess::ForFixedTypedArrayBaseExternalPointer());
HValue* base_pointer = Add<HLoadNamedField>(
elements, nullptr, HObjectAccess::ForFixedTypedArrayBaseBasePointer());
HValue* backing_store = AddUncasted<HAdd>(external_pointer, base_pointer,
AddOfExternalAndTagged);
if (store_mode == STORE_NO_TRANSITION_IGNORE_OUT_OF_BOUNDS) {
NoObservableSideEffectsScope no_effects(this);
IfBuilder length_checker(this);
length_checker.If<HCompareNumericAndBranch>(key, length, Token::LT);
length_checker.Then();
IfBuilder negative_checker(this);
HValue* bounds_check = negative_checker.If<HCompareNumericAndBranch>(
key, graph()->GetConstant0(), Token::GTE);
negative_checker.Then();
HInstruction* result = AddElementAccess(
backing_store, key, val, bounds_check, checked_object->ActualValue(),
elements_kind, access_type);
negative_checker.ElseDeopt(DeoptimizeReason::kNegativeKeyEncountered);
negative_checker.End();
length_checker.End();
return result;
} else {
DCHECK(store_mode == STANDARD_STORE);
checked_key = Add<HBoundsCheck>(key, length);
return AddElementAccess(backing_store, checked_key, val, checked_object,
checked_object->ActualValue(), elements_kind,
access_type);
}
}
DCHECK(fast_smi_only_elements ||
fast_elements ||
IsFastDoubleElementsKind(elements_kind));
// In case val is stored into a fast smi array, assure that the value is a smi
// before manipulating the backing store. Otherwise the actual store may
// deopt, leaving the backing store in an invalid state.
if (access_type == STORE && IsFastSmiElementsKind(elements_kind) &&
!val->type().IsSmi()) {
val = AddUncasted<HForceRepresentation>(val, Representation::Smi());
}
if (IsGrowStoreMode(store_mode)) {
NoObservableSideEffectsScope no_effects(this);
Representation representation = HStoreKeyed::RequiredValueRepresentation(
elements_kind, STORE_TO_INITIALIZED_ENTRY);
val = AddUncasted<HForceRepresentation>(val, representation);
elements = BuildCheckForCapacityGrow(checked_object, elements,
elements_kind, length, key,
is_js_array, access_type);
checked_key = key;
} else {
checked_key = Add<HBoundsCheck>(key, length);
if (access_type == STORE && (fast_elements || fast_smi_only_elements)) {
if (store_mode == STORE_NO_TRANSITION_HANDLE_COW) {
NoObservableSideEffectsScope no_effects(this);
elements = BuildCopyElementsOnWrite(checked_object, elements,
elements_kind, length);
} else {
HCheckMaps* check_cow_map = Add<HCheckMaps>(
elements, isolate()->factory()->fixed_array_map());
check_cow_map->ClearDependsOnFlag(kElementsKind);
}
}
}
return AddElementAccess(elements, checked_key, val, checked_object, nullptr,
elements_kind, access_type, load_mode);
}
HValue* HGraphBuilder::BuildCalculateElementsSize(ElementsKind kind,
HValue* capacity) {
int elements_size = IsFastDoubleElementsKind(kind)
? kDoubleSize
: kPointerSize;
HConstant* elements_size_value = Add<HConstant>(elements_size);
HInstruction* mul =
HMul::NewImul(isolate(), zone(), context(), capacity->ActualValue(),
elements_size_value);
AddInstruction(mul);
mul->ClearFlag(HValue::kCanOverflow);
STATIC_ASSERT(FixedDoubleArray::kHeaderSize == FixedArray::kHeaderSize);
HConstant* header_size = Add<HConstant>(FixedArray::kHeaderSize);
HValue* total_size = AddUncasted<HAdd>(mul, header_size);
total_size->ClearFlag(HValue::kCanOverflow);
return total_size;
}
HAllocate* HGraphBuilder::AllocateJSArrayObject(AllocationSiteMode mode) {
int base_size = JSArray::kSize;
if (mode == TRACK_ALLOCATION_SITE) {
base_size += AllocationMemento::kSize;
}
HConstant* size_in_bytes = Add<HConstant>(base_size);
return Add<HAllocate>(size_in_bytes, HType::JSArray(), NOT_TENURED,
JS_OBJECT_TYPE, graph()->GetConstant0());
}
HConstant* HGraphBuilder::EstablishElementsAllocationSize(
ElementsKind kind,
int capacity) {
int base_size = IsFastDoubleElementsKind(kind)
? FixedDoubleArray::SizeFor(capacity)
: FixedArray::SizeFor(capacity);
return Add<HConstant>(base_size);
}
HAllocate* HGraphBuilder::BuildAllocateElements(ElementsKind kind,
HValue* size_in_bytes) {
InstanceType instance_type = IsFastDoubleElementsKind(kind)
? FIXED_DOUBLE_ARRAY_TYPE
: FIXED_ARRAY_TYPE;
return Add<HAllocate>(size_in_bytes, HType::HeapObject(), NOT_TENURED,
instance_type, graph()->GetConstant0());
}
void HGraphBuilder::BuildInitializeElementsHeader(HValue* elements,
ElementsKind kind,
HValue* capacity) {
Factory* factory = isolate()->factory();
Handle<Map> map = IsFastDoubleElementsKind(kind)
? factory->fixed_double_array_map()
: factory->fixed_array_map();
Add<HStoreNamedField>(elements, HObjectAccess::ForMap(), Add<HConstant>(map));
Add<HStoreNamedField>(elements, HObjectAccess::ForFixedArrayLength(),
capacity);
}
HValue* HGraphBuilder::BuildAllocateAndInitializeArray(ElementsKind kind,
HValue* capacity) {
// The HForceRepresentation is to prevent possible deopt on int-smi
// conversion after allocation but before the new object fields are set.
capacity = AddUncasted<HForceRepresentation>(capacity, Representation::Smi());
HValue* size_in_bytes = BuildCalculateElementsSize(kind, capacity);
HValue* new_array = BuildAllocateElements(kind, size_in_bytes);
BuildInitializeElementsHeader(new_array, kind, capacity);
return new_array;
}
void HGraphBuilder::BuildJSArrayHeader(HValue* array,
HValue* array_map,
HValue* elements,
AllocationSiteMode mode,
ElementsKind elements_kind,
HValue* allocation_site_payload,
HValue* length_field) {
Add<HStoreNamedField>(array, HObjectAccess::ForMap(), array_map);
HValue* empty_fixed_array = Add<HLoadRoot>(Heap::kEmptyFixedArrayRootIndex);
Add<HStoreNamedField>(
array, HObjectAccess::ForPropertiesPointer(), empty_fixed_array);
Add<HStoreNamedField>(array, HObjectAccess::ForElementsPointer(),
elements != nullptr ? elements : empty_fixed_array);
Add<HStoreNamedField>(
array, HObjectAccess::ForArrayLength(elements_kind), length_field);
if (mode == TRACK_ALLOCATION_SITE) {
BuildCreateAllocationMemento(
array, Add<HConstant>(JSArray::kSize), allocation_site_payload);
}
}
HInstruction* HGraphBuilder::AddElementAccess(
HValue* elements, HValue* checked_key, HValue* val, HValue* dependency,
HValue* backing_store_owner, ElementsKind elements_kind,
PropertyAccessType access_type, LoadKeyedHoleMode load_mode) {
if (access_type == STORE) {
DCHECK(val != NULL);
if (elements_kind == UINT8_CLAMPED_ELEMENTS) {
val = Add<HClampToUint8>(val);
}
return Add<HStoreKeyed>(elements, checked_key, val, backing_store_owner,
elements_kind, STORE_TO_INITIALIZED_ENTRY);
}
DCHECK(access_type == LOAD);
DCHECK(val == NULL);
HLoadKeyed* load =
Add<HLoadKeyed>(elements, checked_key, dependency, backing_store_owner,
elements_kind, load_mode);
if (elements_kind == UINT32_ELEMENTS) {
graph()->RecordUint32Instruction(load);
}
return load;
}
HLoadNamedField* HGraphBuilder::AddLoadMap(HValue* object,
HValue* dependency) {
return Add<HLoadNamedField>(object, dependency, HObjectAccess::ForMap());
}
HLoadNamedField* HGraphBuilder::AddLoadElements(HValue* object,
HValue* dependency) {
return Add<HLoadNamedField>(
object, dependency, HObjectAccess::ForElementsPointer());
}
HLoadNamedField* HGraphBuilder::AddLoadFixedArrayLength(
HValue* array,
HValue* dependency) {
return Add<HLoadNamedField>(
array, dependency, HObjectAccess::ForFixedArrayLength());
}
HLoadNamedField* HGraphBuilder::AddLoadArrayLength(HValue* array,
ElementsKind kind,
HValue* dependency) {
return Add<HLoadNamedField>(
array, dependency, HObjectAccess::ForArrayLength(kind));
}
HValue* HGraphBuilder::BuildNewElementsCapacity(HValue* old_capacity) {
HValue* half_old_capacity = AddUncasted<HShr>(old_capacity,
graph_->GetConstant1());
HValue* new_capacity = AddUncasted<HAdd>(half_old_capacity, old_capacity);
new_capacity->ClearFlag(HValue::kCanOverflow);
HValue* min_growth = Add<HConstant>(16);
new_capacity = AddUncasted<HAdd>(new_capacity, min_growth);
new_capacity->ClearFlag(HValue::kCanOverflow);
return new_capacity;
}
HValue* HGraphBuilder::BuildGrowElementsCapacity(HValue* object,
HValue* elements,
ElementsKind kind,
ElementsKind new_kind,
HValue* length,
HValue* new_capacity) {
Add<HBoundsCheck>(
new_capacity,
Add<HConstant>((kMaxRegularHeapObjectSize - FixedArray::kHeaderSize) >>
ElementsKindToShiftSize(new_kind)));
HValue* new_elements =
BuildAllocateAndInitializeArray(new_kind, new_capacity);
BuildCopyElements(elements, kind, new_elements,
new_kind, length, new_capacity);
Add<HStoreNamedField>(object, HObjectAccess::ForElementsPointer(),
new_elements);
return new_elements;
}
void HGraphBuilder::BuildFillElementsWithValue(HValue* elements,
ElementsKind elements_kind,
HValue* from,
HValue* to,
HValue* value) {
if (to == NULL) {
to = AddLoadFixedArrayLength(elements);
}
// Special loop unfolding case
STATIC_ASSERT(JSArray::kPreallocatedArrayElements <=
kElementLoopUnrollThreshold);
int initial_capacity = -1;
if (from->IsInteger32Constant() && to->IsInteger32Constant()) {
int constant_from = from->GetInteger32Constant();
int constant_to = to->GetInteger32Constant();
if (constant_from == 0 && constant_to <= kElementLoopUnrollThreshold) {
initial_capacity = constant_to;
}
}
if (initial_capacity >= 0) {
for (int i = 0; i < initial_capacity; i++) {
HInstruction* key = Add<HConstant>(i);
Add<HStoreKeyed>(elements, key, value, nullptr, elements_kind);
}
} else {
// Carefully loop backwards so that the "from" remains live through the loop
// rather than the to. This often corresponds to keeping length live rather
// then capacity, which helps register allocation, since length is used more
// other than capacity after filling with holes.
LoopBuilder builder(this, context(), LoopBuilder::kPostDecrement);
HValue* key = builder.BeginBody(to, from, Token::GT);
HValue* adjusted_key = AddUncasted<HSub>(key, graph()->GetConstant1());
adjusted_key->ClearFlag(HValue::kCanOverflow);
Add<HStoreKeyed>(elements, adjusted_key, value, nullptr, elements_kind);
builder.EndBody();
}
}
void HGraphBuilder::BuildFillElementsWithHole(HValue* elements,
ElementsKind elements_kind,
HValue* from,
HValue* to) {
// Fast elements kinds need to be initialized in case statements below cause a
// garbage collection.
HValue* hole = IsFastSmiOrObjectElementsKind(elements_kind)
? graph()->GetConstantHole()
: Add<HConstant>(HConstant::kHoleNaN);
// Since we're about to store a hole value, the store instruction below must
// assume an elements kind that supports heap object values.
if (IsFastSmiOrObjectElementsKind(elements_kind)) {
elements_kind = FAST_HOLEY_ELEMENTS;
}
BuildFillElementsWithValue(elements, elements_kind, from, to, hole);
}
void HGraphBuilder::BuildCopyProperties(HValue* from_properties,
HValue* to_properties, HValue* length,
HValue* capacity) {
ElementsKind kind = FAST_ELEMENTS;
BuildFillElementsWithValue(to_properties, kind, length, capacity,
graph()->GetConstantUndefined());
LoopBuilder builder(this, context(), LoopBuilder::kPostDecrement);
HValue* key = builder.BeginBody(length, graph()->GetConstant0(), Token::GT);
key = AddUncasted<HSub>(key, graph()->GetConstant1());
key->ClearFlag(HValue::kCanOverflow);
HValue* element =
Add<HLoadKeyed>(from_properties, key, nullptr, nullptr, kind);
Add<HStoreKeyed>(to_properties, key, element, nullptr, kind);
builder.EndBody();
}
void HGraphBuilder::BuildCopyElements(HValue* from_elements,
ElementsKind from_elements_kind,
HValue* to_elements,
ElementsKind to_elements_kind,
HValue* length,
HValue* capacity) {
int constant_capacity = -1;
if (capacity != NULL &&
capacity->IsConstant() &&
HConstant::cast(capacity)->HasInteger32Value()) {
int constant_candidate = HConstant::cast(capacity)->Integer32Value();
if (constant_candidate <= kElementLoopUnrollThreshold) {
constant_capacity = constant_candidate;
}
}
bool pre_fill_with_holes =
IsFastDoubleElementsKind(from_elements_kind) &&
IsFastObjectElementsKind(to_elements_kind);
if (pre_fill_with_holes) {
// If the copy might trigger a GC, make sure that the FixedArray is
// pre-initialized with holes to make sure that it's always in a
// consistent state.
BuildFillElementsWithHole(to_elements, to_elements_kind,
graph()->GetConstant0(), NULL);
}
if (constant_capacity != -1) {
// Unroll the loop for small elements kinds.
for (int i = 0; i < constant_capacity; i++) {
HValue* key_constant = Add<HConstant>(i);
HInstruction* value = Add<HLoadKeyed>(
from_elements, key_constant, nullptr, nullptr, from_elements_kind);
Add<HStoreKeyed>(to_elements, key_constant, value, nullptr,
to_elements_kind);
}
} else {
if (!pre_fill_with_holes &&
(capacity == NULL || !length->Equals(capacity))) {
BuildFillElementsWithHole(to_elements, to_elements_kind,
length, NULL);
}
LoopBuilder builder(this, context(), LoopBuilder::kPostDecrement);
HValue* key = builder.BeginBody(length, graph()->GetConstant0(),
Token::GT);
key = AddUncasted<HSub>(key, graph()->GetConstant1());
key->ClearFlag(HValue::kCanOverflow);
HValue* element = Add<HLoadKeyed>(from_elements, key, nullptr, nullptr,
from_elements_kind, ALLOW_RETURN_HOLE);
ElementsKind kind = (IsHoleyElementsKind(from_elements_kind) &&
IsFastSmiElementsKind(to_elements_kind))
? FAST_HOLEY_ELEMENTS : to_elements_kind;
if (IsHoleyElementsKind(from_elements_kind) &&
from_elements_kind != to_elements_kind) {
IfBuilder if_hole(this);
if_hole.If<HCompareHoleAndBranch>(element);
if_hole.Then();
HConstant* hole_constant = IsFastDoubleElementsKind(to_elements_kind)
? Add<HConstant>(HConstant::kHoleNaN)
: graph()->GetConstantHole();
Add<HStoreKeyed>(to_elements, key, hole_constant, nullptr, kind);
if_hole.Else();
HStoreKeyed* store =
Add<HStoreKeyed>(to_elements, key, element, nullptr, kind);
store->SetFlag(HValue::kTruncatingToNumber);
if_hole.End();
} else {
HStoreKeyed* store =
Add<HStoreKeyed>(to_elements, key, element, nullptr, kind);
store->SetFlag(HValue::kTruncatingToNumber);
}
builder.EndBody();
}
Counters* counters = isolate()->counters();
AddIncrementCounter(counters->inlined_copied_elements());
}
void HGraphBuilder::BuildCreateAllocationMemento(
HValue* previous_object,
HValue* previous_object_size,
HValue* allocation_site) {
DCHECK(allocation_site != NULL);
HInnerAllocatedObject* allocation_memento = Add<HInnerAllocatedObject>(
previous_object, previous_object_size, HType::HeapObject());
AddStoreMapConstant(
allocation_memento, isolate()->factory()->allocation_memento_map());
Add<HStoreNamedField>(
allocation_memento,
HObjectAccess::ForAllocationMementoSite(),
allocation_site);
if (FLAG_allocation_site_pretenuring) {
HValue* memento_create_count =
Add<HLoadNamedField>(allocation_site, nullptr,
HObjectAccess::ForAllocationSiteOffset(
AllocationSite::kPretenureCreateCountOffset));
memento_create_count = AddUncasted<HAdd>(
memento_create_count, graph()->GetConstant1());
// This smi value is reset to zero after every gc, overflow isn't a problem
// since the counter is bounded by the new space size.
memento_create_count->ClearFlag(HValue::kCanOverflow);
Add<HStoreNamedField>(
allocation_site, HObjectAccess::ForAllocationSiteOffset(
AllocationSite::kPretenureCreateCountOffset), memento_create_count);
}
}
HInstruction* HGraphBuilder::BuildGetNativeContext() {
return Add<HLoadNamedField>(
context(), nullptr,
HObjectAccess::ForContextSlot(Context::NATIVE_CONTEXT_INDEX));
}
HValue* HGraphBuilder::BuildArrayBufferViewFieldAccessor(HValue* object,
HValue* checked_object,
FieldIndex index) {
NoObservableSideEffectsScope scope(this);
HObjectAccess access = HObjectAccess::ForObservableJSObjectOffset(
index.offset(), Representation::Tagged());
HInstruction* buffer = Add<HLoadNamedField>(
object, checked_object, HObjectAccess::ForJSArrayBufferViewBuffer());
HInstruction* field = Add<HLoadNamedField>(object, checked_object, access);
HInstruction* flags = Add<HLoadNamedField>(
buffer, nullptr, HObjectAccess::ForJSArrayBufferBitField());
HValue* was_neutered_mask =
Add<HConstant>(1 << JSArrayBuffer::WasNeutered::kShift);
HValue* was_neutered_test =
AddUncasted<HBitwise>(Token::BIT_AND, flags, was_neutered_mask);
IfBuilder if_was_neutered(this);
if_was_neutered.If<HCompareNumericAndBranch>(
was_neutered_test, graph()->GetConstant0(), Token::NE);
if_was_neutered.Then();
Push(graph()->GetConstant0());
if_was_neutered.Else();
Push(field);
if_was_neutered.End();
return Pop();
}
HOptimizedGraphBuilder::HOptimizedGraphBuilder(CompilationInfo* info,
bool track_positions)
: HGraphBuilder(info, CallInterfaceDescriptor(), track_positions),
function_state_(NULL),
initial_function_state_(this, info, NORMAL_RETURN, -1,
TailCallMode::kAllow),
ast_context_(NULL),
break_scope_(NULL),
inlined_count_(0),
globals_(10, info->zone()),
osr_(new (info->zone()) HOsrBuilder(this)),
bounds_(info->zone()) {
// This is not initialized in the initializer list because the
// constructor for the initial state relies on function_state_ == NULL
// to know it's the initial state.
function_state_ = &initial_function_state_;
InitializeAstVisitor(info->isolate());
}
HBasicBlock* HOptimizedGraphBuilder::CreateJoin(HBasicBlock* first,
HBasicBlock* second,
BailoutId join_id) {
if (first == NULL) {
return second;
} else if (second == NULL) {
return first;
} else {
HBasicBlock* join_block = graph()->CreateBasicBlock();
Goto(first, join_block);
Goto(second, join_block);
join_block->SetJoinId(join_id);
return join_block;
}
}
HBasicBlock* HOptimizedGraphBuilder::JoinContinue(IterationStatement* statement,
BailoutId continue_id,
HBasicBlock* exit_block,
HBasicBlock* continue_block) {
if (continue_block != NULL) {
if (exit_block != NULL) Goto(exit_block, continue_block);
continue_block->SetJoinId(continue_id);
return continue_block;
}
return exit_block;
}
HBasicBlock* HOptimizedGraphBuilder::CreateLoop(IterationStatement* statement,
HBasicBlock* loop_entry,
HBasicBlock* body_exit,
HBasicBlock* loop_successor,
HBasicBlock* break_block) {
if (body_exit != NULL) Goto(body_exit, loop_entry);
loop_entry->PostProcessLoopHeader(statement);
if (break_block != NULL) {
if (loop_successor != NULL) Goto(loop_successor, break_block);
break_block->SetJoinId(statement->ExitId());
return break_block;
}
return loop_successor;
}
// Build a new loop header block and set it as the current block.
HBasicBlock* HOptimizedGraphBuilder::BuildLoopEntry() {
HBasicBlock* loop_entry = CreateLoopHeaderBlock();
Goto(loop_entry);
set_current_block(loop_entry);
return loop_entry;
}
HBasicBlock* HOptimizedGraphBuilder::BuildLoopEntry(
IterationStatement* statement) {
HBasicBlock* loop_entry;
if (osr()->HasOsrEntryAt(statement)) {
loop_entry = osr()->BuildOsrLoopEntry(statement);
if (function_state()->IsInsideDoExpressionScope()) {
Bailout(kDoExpressionUnmodelable);
}
} else {
loop_entry = BuildLoopEntry();
}
return loop_entry;
}
void HBasicBlock::FinishExit(HControlInstruction* instruction,
SourcePosition position) {
Finish(instruction, position);
ClearEnvironment();
}
std::ostream& operator<<(std::ostream& os, const HBasicBlock& b) {
return os << "B" << b.block_id();
}
HGraph::HGraph(CompilationInfo* info, CallInterfaceDescriptor descriptor)
: isolate_(info->isolate()),
next_block_id_(0),
entry_block_(NULL),
blocks_(8, info->zone()),
values_(16, info->zone()),
phi_list_(NULL),
uint32_instructions_(NULL),
osr_(NULL),
info_(info),
descriptor_(descriptor),
zone_(info->zone()),
allow_code_motion_(false),
use_optimistic_licm_(false),
depends_on_empty_array_proto_elements_(false),
depends_on_string_length_overflow_(false),
type_change_checksum_(0),
maximum_environment_size_(0),
no_side_effects_scope_count_(0),
disallow_adding_new_values_(false) {
if (info->IsStub()) {
// For stubs, explicitly add the context to the environment.
start_environment_ =
new (zone_) HEnvironment(zone_, descriptor.GetParameterCount() + 1);
} else {
start_environment_ =
new(zone_) HEnvironment(NULL, info->scope(), info->closure(), zone_);
}
start_environment_->set_ast_id(BailoutId::FunctionContext());
entry_block_ = CreateBasicBlock();
entry_block_->SetInitialEnvironment(start_environment_);
}
HBasicBlock* HGraph::CreateBasicBlock() {
HBasicBlock* result = new(zone()) HBasicBlock(this);
blocks_.Add(result, zone());
return result;
}
void HGraph::FinalizeUniqueness() {
DisallowHeapAllocation no_gc;
for (int i = 0; i < blocks()->length(); ++i) {
for (HInstructionIterator it(blocks()->at(i)); !it.Done(); it.Advance()) {
it.Current()->FinalizeUniqueness();
}
}
}
// Block ordering was implemented with two mutually recursive methods,
// HGraph::Postorder and HGraph::PostorderLoopBlocks.
// The recursion could lead to stack overflow so the algorithm has been
// implemented iteratively.
// At a high level the algorithm looks like this:
//
// Postorder(block, loop_header) : {
// if (block has already been visited or is of another loop) return;
// mark block as visited;
// if (block is a loop header) {
// VisitLoopMembers(block, loop_header);
// VisitSuccessorsOfLoopHeader(block);
// } else {
// VisitSuccessors(block)
// }
// put block in result list;
// }
//
// VisitLoopMembers(block, outer_loop_header) {
// foreach (block b in block loop members) {
// VisitSuccessorsOfLoopMember(b, outer_loop_header);
// if (b is loop header) VisitLoopMembers(b);
// }
// }
//
// VisitSuccessorsOfLoopMember(block, outer_loop_header) {
// foreach (block b in block successors) Postorder(b, outer_loop_header)
// }
//
// VisitSuccessorsOfLoopHeader(block) {
// foreach (block b in block successors) Postorder(b, block)
// }
//
// VisitSuccessors(block, loop_header) {
// foreach (block b in block successors) Postorder(b, loop_header)
// }
//
// The ordering is started calling Postorder(entry, NULL).
//
// Each instance of PostorderProcessor represents the "stack frame" of the
// recursion, and particularly keeps the state of the loop (iteration) of the
// "Visit..." function it represents.
// To recycle memory we keep all the frames in a double linked list but
// this means that we cannot use constructors to initialize the frames.
//
class PostorderProcessor : public ZoneObject {
public:
// Back link (towards the stack bottom).
PostorderProcessor* parent() {return father_; }
// Forward link (towards the stack top).
PostorderProcessor* child() {return child_; }
HBasicBlock* block() { return block_; }
HLoopInformation* loop() { return loop_; }
HBasicBlock* loop_header() { return loop_header_; }
static PostorderProcessor* CreateEntryProcessor(Zone* zone,
HBasicBlock* block) {
PostorderProcessor* result = new(zone) PostorderProcessor(NULL);
return result->SetupSuccessors(zone, block, NULL);
}
PostorderProcessor* PerformStep(Zone* zone,
ZoneList<HBasicBlock*>* order) {
PostorderProcessor* next =
PerformNonBacktrackingStep(zone, order);
if (next != NULL) {
return next;
} else {
return Backtrack(zone, order);
}
}
private:
explicit PostorderProcessor(PostorderProcessor* father)
: father_(father), child_(NULL), successor_iterator(NULL) { }
// Each enum value states the cycle whose state is kept by this instance.
enum LoopKind {
NONE,
SUCCESSORS,
SUCCESSORS_OF_LOOP_HEADER,
LOOP_MEMBERS,
SUCCESSORS_OF_LOOP_MEMBER
};
// Each "Setup..." method is like a constructor for a cycle state.
PostorderProcessor* SetupSuccessors(Zone* zone,
HBasicBlock* block,
HBasicBlock* loop_header) {
if (block == NULL || block->IsOrdered() ||
block->parent_loop_header() != loop_header) {
kind_ = NONE;
block_ = NULL;
loop_ = NULL;
loop_header_ = NULL;
return this;
} else {
block_ = block;
loop_ = NULL;
block->MarkAsOrdered();
if (block->IsLoopHeader()) {
kind_ = SUCCESSORS_OF_LOOP_HEADER;
loop_header_ = block;
InitializeSuccessors();
PostorderProcessor* result = Push(zone);
return result->SetupLoopMembers(zone, block, block->loop_information(),
loop_header);
} else {
DCHECK(block->IsFinished());
kind_ = SUCCESSORS;
loop_header_ = loop_header;
InitializeSuccessors();
return this;
}
}
}
PostorderProcessor* SetupLoopMembers(Zone* zone,
HBasicBlock* block,
HLoopInformation* loop,
HBasicBlock* loop_header) {
kind_ = LOOP_MEMBERS;
block_ = block;
loop_ = loop;
loop_header_ = loop_header;
InitializeLoopMembers();
return this;
}
PostorderProcessor* SetupSuccessorsOfLoopMember(
HBasicBlock* block,
HLoopInformation* loop,
HBasicBlock* loop_header) {
kind_ = SUCCESSORS_OF_LOOP_MEMBER;
block_ = block;
loop_ = loop;
loop_header_ = loop_header;
InitializeSuccessors();
return this;
}
// This method "allocates" a new stack frame.
PostorderProcessor* Push(Zone* zone) {
if (child_ == NULL) {
child_ = new(zone) PostorderProcessor(this);
}
return child_;
}
void ClosePostorder(ZoneList<HBasicBlock*>* order, Zone* zone) {
DCHECK(block_->end()->FirstSuccessor() == NULL ||
order->Contains(block_->end()->FirstSuccessor()) ||
block_->end()->FirstSuccessor()->IsLoopHeader());
DCHECK(block_->end()->SecondSuccessor() == NULL ||
order->Contains(block_->end()->SecondSuccessor()) ||
block_->end()->SecondSuccessor()->IsLoopHeader());
order->Add(block_, zone);
}
// This method is the basic block to walk up the stack.
PostorderProcessor* Pop(Zone* zone,
ZoneList<HBasicBlock*>* order) {
switch (kind_) {
case SUCCESSORS:
case SUCCESSORS_OF_LOOP_HEADER:
ClosePostorder(order, zone);
return father_;
case LOOP_MEMBERS:
return father_;
case SUCCESSORS_OF_LOOP_MEMBER:
if (block()->IsLoopHeader() && block() != loop_->loop_header()) {
// In this case we need to perform a LOOP_MEMBERS cycle so we
// initialize it and return this instead of father.
return SetupLoopMembers(zone, block(),
block()->loop_information(), loop_header_);
} else {
return father_;
}
case NONE:
return father_;
}
UNREACHABLE();
}
// Walks up the stack.
PostorderProcessor* Backtrack(Zone* zone,
ZoneList<HBasicBlock*>* order) {
PostorderProcessor* parent = Pop(zone, order);
while (parent != NULL) {
PostorderProcessor* next =
parent->PerformNonBacktrackingStep(zone, order);
if (next != NULL) {
return next;
} else {
parent = parent->Pop(zone, order);
}
}
return NULL;
}
PostorderProcessor* PerformNonBacktrackingStep(
Zone* zone,
ZoneList<HBasicBlock*>* order) {
HBasicBlock* next_block;
switch (kind_) {
case SUCCESSORS:
next_block = AdvanceSuccessors();
if (next_block != NULL) {
PostorderProcessor* result = Push(zone);
return result->SetupSuccessors(zone, next_block, loop_header_);
}
break;
case SUCCESSORS_OF_LOOP_HEADER:
next_block = AdvanceSuccessors();
if (next_block != NULL) {
PostorderProcessor* result = Push(zone);
return result->SetupSuccessors(zone, next_block, block());
}
break;
case LOOP_MEMBERS:
next_block = AdvanceLoopMembers();
if (next_block != NULL) {
PostorderProcessor* result = Push(zone);
return result->SetupSuccessorsOfLoopMember(next_block,
loop_, loop_header_);
}
break;
case SUCCESSORS_OF_LOOP_MEMBER:
next_block = AdvanceSuccessors();
if (next_block != NULL) {
PostorderProcessor* result = Push(zone);
return result->SetupSuccessors(zone, next_block, loop_header_);
}
break;
case NONE:
return NULL;
}
return NULL;
}
// The following two methods implement a "foreach b in successors" cycle.
void InitializeSuccessors() {
loop_index = 0;
loop_length = 0;
successor_iterator = HSuccessorIterator(block_->end());
}
HBasicBlock* AdvanceSuccessors() {
if (!successor_iterator.Done()) {
HBasicBlock* result = successor_iterator.Current();
successor_iterator.Advance();
return result;
}
return NULL;
}
// The following two methods implement a "foreach b in loop members" cycle.
void InitializeLoopMembers() {
loop_index = 0;
loop_length = loop_->blocks()->length();
}
HBasicBlock* AdvanceLoopMembers() {
if (loop_index < loop_length) {
HBasicBlock* result = loop_->blocks()->at(loop_index);
loop_index++;
return result;
} else {
return NULL;
}
}
LoopKind kind_;
PostorderProcessor* father_;
PostorderProcessor* child_;
HLoopInformation* loop_;
HBasicBlock* block_;
HBasicBlock* loop_header_;
int loop_index;
int loop_length;
HSuccessorIterator successor_iterator;
};
void HGraph::OrderBlocks() {
CompilationPhase phase("H_Block ordering", info());
#ifdef DEBUG
// Initially the blocks must not be ordered.
for (int i = 0; i < blocks_.length(); ++i) {
DCHECK(!blocks_[i]->IsOrdered());
}
#endif
PostorderProcessor* postorder =
PostorderProcessor::CreateEntryProcessor(zone(), blocks_[0]);
blocks_.Rewind(0);
while (postorder) {
postorder = postorder->PerformStep(zone(), &blocks_);
}
#ifdef DEBUG
// Now all blocks must be marked as ordered.
for (int i = 0; i < blocks_.length(); ++i) {
DCHECK(blocks_[i]->IsOrdered());
}
#endif
// Reverse block list and assign block IDs.
for (int i = 0, j = blocks_.length(); --j >= i; ++i) {
HBasicBlock* bi = blocks_[i];
HBasicBlock* bj = blocks_[j];
bi->set_block_id(j);
bj->set_block_id(i);
blocks_[i] = bj;
blocks_[j] = bi;
}
}
void HGraph::AssignDominators() {
HPhase phase("H_Assign dominators", this);
for (int i = 0; i < blocks_.length(); ++i) {
HBasicBlock* block = blocks_[i];
if (block->IsLoopHeader()) {
// Only the first predecessor of a loop header is from outside the loop.
// All others are back edges, and thus cannot dominate the loop header.
block->AssignCommonDominator(block->predecessors()->first());
block->AssignLoopSuccessorDominators();
} else {
for (int j = blocks_[i]->predecessors()->length() - 1; j >= 0; --j) {
blocks_[i]->AssignCommonDominator(blocks_[i]->predecessors()->at(j));
}
}
}
}
bool HGraph::CheckArgumentsPhiUses() {
int block_count = blocks_.length();
for (int i = 0; i < block_count; ++i) {
for (int j = 0; j < blocks_[i]->phis()->length(); ++j) {
HPhi* phi = blocks_[i]->phis()->at(j);
// We don't support phi uses of arguments for now.
if (phi->CheckFlag(HValue::kIsArguments)) return false;
}
}
return true;
}
bool HGraph::CheckConstPhiUses() {
int block_count = blocks_.length();
for (int i = 0; i < block_count; ++i) {
for (int j = 0; j < blocks_[i]->phis()->length(); ++j) {
HPhi* phi = blocks_[i]->phis()->at(j);
// Check for the hole value (from an uninitialized const).
for (int k = 0; k < phi->OperandCount(); k++) {
if (phi->OperandAt(k) == GetConstantHole()) return false;
}
}
}
return true;
}
void HGraph::CollectPhis() {
int block_count = blocks_.length();
phi_list_ = new(zone()) ZoneList<HPhi*>(block_count, zone());
for (int i = 0; i < block_count; ++i) {
for (int j = 0; j < blocks_[i]->phis()->length(); ++j) {
HPhi* phi = blocks_[i]->phis()->at(j);
phi_list_->Add(phi, zone());
}
}
}
// Implementation of utility class to encapsulate the translation state for
// a (possibly inlined) function.
FunctionState::FunctionState(HOptimizedGraphBuilder* owner,
CompilationInfo* info, InliningKind inlining_kind,
int inlining_id, TailCallMode tail_call_mode)
: owner_(owner),
compilation_info_(info),
call_context_(NULL),
inlining_kind_(inlining_kind),
tail_call_mode_(tail_call_mode),
function_return_(NULL),
test_context_(NULL),
entry_(NULL),
arguments_object_(NULL),
arguments_elements_(NULL),
inlining_id_(inlining_id),
outer_source_position_(SourcePosition::Unknown()),
do_expression_scope_count_(0),
outer_(owner->function_state()) {
if (outer_ != NULL) {
// State for an inline function.
if (owner->ast_context()->IsTest()) {
HBasicBlock* if_true = owner->graph()->CreateBasicBlock();
HBasicBlock* if_false = owner->graph()->CreateBasicBlock();
if_true->MarkAsInlineReturnTarget(owner->current_block());
if_false->MarkAsInlineReturnTarget(owner->current_block());
TestContext* outer_test_context = TestContext::cast(owner->ast_context());
Expression* cond = outer_test_context->condition();
// The AstContext constructor pushed on the context stack. This newed
// instance is the reason that AstContext can't be BASE_EMBEDDED.
test_context_ = new TestContext(owner, cond, if_true, if_false);
} else {
function_return_ = owner->graph()->CreateBasicBlock();
function_return()->MarkAsInlineReturnTarget(owner->current_block());
}
// Set this after possibly allocating a new TestContext above.
call_context_ = owner->ast_context();
}
// Push on the state stack.
owner->set_function_state(this);
if (owner->is_tracking_positions()) {
outer_source_position_ = owner->source_position();
owner->EnterInlinedSource(inlining_id);
owner->SetSourcePosition(info->shared_info()->start_position());
}
}
FunctionState::~FunctionState() {
delete test_context_;
owner_->set_function_state(outer_);
if (owner_->is_tracking_positions()) {
owner_->set_source_position(outer_source_position_);
owner_->EnterInlinedSource(outer_->inlining_id());
}
}
// Implementation of utility classes to represent an expression's context in
// the AST.
AstContext::AstContext(HOptimizedGraphBuilder* owner, Expression::Context kind)
: owner_(owner),
kind_(kind),
outer_(owner->ast_context()),
typeof_mode_(NOT_INSIDE_TYPEOF) {
owner->set_ast_context(this); // Push.
#ifdef DEBUG
DCHECK_EQ(JS_FUNCTION, owner->environment()->frame_type());
original_length_ = owner->environment()->length();
#endif
}
AstContext::~AstContext() {
owner_->set_ast_context(outer_); // Pop.
}
EffectContext::~EffectContext() {
DCHECK(owner()->HasStackOverflow() || owner()->current_block() == NULL ||
(owner()->environment()->length() == original_length_ &&
(owner()->environment()->frame_type() == JS_FUNCTION ||
owner()->environment()->frame_type() == TAIL_CALLER_FUNCTION)));
}
ValueContext::~ValueContext() {
DCHECK(owner()->HasStackOverflow() || owner()->current_block() == NULL ||
(owner()->environment()->length() == original_length_ + 1 &&
(owner()->environment()->frame_type() == JS_FUNCTION ||
owner()->environment()->frame_type() == TAIL_CALLER_FUNCTION)));
}
void EffectContext::ReturnValue(HValue* value) {
// The value is simply ignored.
}
void ValueContext::ReturnValue(HValue* value) {
// The value is tracked in the bailout environment, and communicated
// through the environment as the result of the expression.
if (value->CheckFlag(HValue::kIsArguments)) {
if (flag_ == ARGUMENTS_FAKED) {
value = owner()->graph()->GetConstantUndefined();
} else if (!arguments_allowed()) {
owner()->Bailout(kBadValueContextForArgumentsValue);
}
}
owner()->Push(value);
}
void TestContext::ReturnValue(HValue* value) {
BuildBranch(value);
}
void EffectContext::ReturnInstruction(HInstruction* instr, BailoutId ast_id) {
DCHECK(!instr->IsControlInstruction());
owner()->AddInstruction(instr);
if (instr->HasObservableSideEffects()) {
owner()->Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
}
}
void EffectContext::ReturnControl(HControlInstruction* instr,
BailoutId ast_id) {
DCHECK(!instr->HasObservableSideEffects());
HBasicBlock* empty_true = owner()->graph()->CreateBasicBlock();
HBasicBlock* empty_false = owner()->graph()->CreateBasicBlock();
instr->SetSuccessorAt(0, empty_true);
instr->SetSuccessorAt(1, empty_false);
owner()->FinishCurrentBlock(instr);
HBasicBlock* join = owner()->CreateJoin(empty_true, empty_false, ast_id);
owner()->set_current_block(join);
}
void EffectContext::ReturnContinuation(HIfContinuation* continuation,
BailoutId ast_id) {
HBasicBlock* true_branch = NULL;
HBasicBlock* false_branch = NULL;
continuation->Continue(&true_branch, &false_branch);
if (!continuation->IsTrueReachable()) {
owner()->set_current_block(false_branch);
} else if (!continuation->IsFalseReachable()) {
owner()->set_current_block(true_branch);
} else {
HBasicBlock* join = owner()->CreateJoin(true_branch, false_branch, ast_id);
owner()->set_current_block(join);
}
}
void ValueContext::ReturnInstruction(HInstruction* instr, BailoutId ast_id) {
DCHECK(!instr->IsControlInstruction());
if (!arguments_allowed() && instr->CheckFlag(HValue::kIsArguments)) {
return owner()->Bailout(kBadValueContextForArgumentsObjectValue);
}
owner()->AddInstruction(instr);
owner()->Push(instr);
if (instr->HasObservableSideEffects()) {
owner()->Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
}
}
void ValueContext::ReturnControl(HControlInstruction* instr, BailoutId ast_id) {
DCHECK(!instr->HasObservableSideEffects());
if (!arguments_allowed() && instr->CheckFlag(HValue::kIsArguments)) {
return owner()->Bailout(kBadValueContextForArgumentsObjectValue);
}
HBasicBlock* materialize_false = owner()->graph()->CreateBasicBlock();
HBasicBlock* materialize_true = owner()->graph()->CreateBasicBlock();
instr->SetSuccessorAt(0, materialize_true);
instr->SetSuccessorAt(1, materialize_false);
owner()->FinishCurrentBlock(instr);
owner()->set_current_block(materialize_true);
owner()->Push(owner()->graph()->GetConstantTrue());
owner()->set_current_block(materialize_false);
owner()->Push(owner()->graph()->GetConstantFalse());
HBasicBlock* join =
owner()->CreateJoin(materialize_true, materialize_false, ast_id);
owner()->set_current_block(join);
}
void ValueContext::ReturnContinuation(HIfContinuation* continuation,
BailoutId ast_id) {
HBasicBlock* materialize_true = NULL;
HBasicBlock* materialize_false = NULL;
continuation->Continue(&materialize_true, &materialize_false);
if (continuation->IsTrueReachable()) {
owner()->set_current_block(materialize_true);
owner()->Push(owner()->graph()->GetConstantTrue());
owner()->set_current_block(materialize_true);
}
if (continuation->IsFalseReachable()) {
owner()->set_current_block(materialize_false);
owner()->Push(owner()->graph()->GetConstantFalse());
owner()->set_current_block(materialize_false);
}
if (continuation->TrueAndFalseReachable()) {
HBasicBlock* join =
owner()->CreateJoin(materialize_true, materialize_false, ast_id);
owner()->set_current_block(join);
}
}
void TestContext::ReturnInstruction(HInstruction* instr, BailoutId ast_id) {
DCHECK(!instr->IsControlInstruction());
HOptimizedGraphBuilder* builder = owner();
builder->AddInstruction(instr);
// We expect a simulate after every expression with side effects, though
// this one isn't actually needed (and wouldn't work if it were targeted).
if (instr->HasObservableSideEffects()) {
builder->Push(instr);
builder->Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
builder->Pop();
}
BuildBranch(instr);
}
void TestContext::ReturnControl(HControlInstruction* instr, BailoutId ast_id) {
DCHECK(!instr->HasObservableSideEffects());
HBasicBlock* empty_true = owner()->graph()->CreateBasicBlock();
HBasicBlock* empty_false = owner()->graph()->CreateBasicBlock();
instr->SetSuccessorAt(0, empty_true);
instr->SetSuccessorAt(1, empty_false);
owner()->FinishCurrentBlock(instr);
owner()->Goto(empty_true, if_true(), owner()->function_state());
owner()->Goto(empty_false, if_false(), owner()->function_state());
owner()->set_current_block(NULL);
}
void TestContext::ReturnContinuation(HIfContinuation* continuation,
BailoutId ast_id) {
HBasicBlock* true_branch = NULL;
HBasicBlock* false_branch = NULL;
continuation->Continue(&true_branch, &false_branch);
if (continuation->IsTrueReachable()) {
owner()->Goto(true_branch, if_true(), owner()->function_state());
}
if (continuation->IsFalseReachable()) {
owner()->Goto(false_branch, if_false(), owner()->function_state());
}
owner()->set_current_block(NULL);
}
void TestContext::BuildBranch(HValue* value) {
// We expect the graph to be in edge-split form: there is no edge that
// connects a branch node to a join node. We conservatively ensure that
// property by always adding an empty block on the outgoing edges of this
// branch.
HOptimizedGraphBuilder* builder = owner();
if (value != NULL && value->CheckFlag(HValue::kIsArguments)) {
builder->Bailout(kArgumentsObjectValueInATestContext);
}
ToBooleanHints expected(condition()->to_boolean_types());
ReturnControl(owner()->New<HBranch>(value, expected), BailoutId::None());
}
// HOptimizedGraphBuilder infrastructure for bailing out and checking bailouts.
#define CHECK_BAILOUT(call) \
do { \
call; \
if (HasStackOverflow()) return; \
} while (false)
#define CHECK_ALIVE(call) \
do { \
call; \
if (HasStackOverflow() || current_block() == NULL) return; \
} while (false)
#define CHECK_ALIVE_OR_RETURN(call, value) \
do { \
call; \
if (HasStackOverflow() || current_block() == NULL) return value; \
} while (false)
void HOptimizedGraphBuilder::Bailout(BailoutReason reason) {
current_info()->AbortOptimization(reason);
SetStackOverflow();
}
void HOptimizedGraphBuilder::VisitForEffect(Expression* expr) {
EffectContext for_effect(this);
Visit(expr);
}
void HOptimizedGraphBuilder::VisitForValue(Expression* expr,
ArgumentsAllowedFlag flag) {
ValueContext for_value(this, flag);
Visit(expr);
}
void HOptimizedGraphBuilder::VisitForTypeOf(Expression* expr) {
ValueContext for_value(this, ARGUMENTS_NOT_ALLOWED);
for_value.set_typeof_mode(INSIDE_TYPEOF);
Visit(expr);
}
void HOptimizedGraphBuilder::VisitForControl(Expression* expr,
HBasicBlock* true_block,
HBasicBlock* false_block) {
TestContext for_control(this, expr, true_block, false_block);
Visit(expr);
}
void HOptimizedGraphBuilder::VisitExpressions(
ZoneList<Expression*>* exprs) {
for (int i = 0; i < exprs->length(); ++i) {
CHECK_ALIVE(VisitForValue(exprs->at(i)));
}
}
void HOptimizedGraphBuilder::VisitExpressions(ZoneList<Expression*>* exprs,
ArgumentsAllowedFlag flag) {
for (int i = 0; i < exprs->length(); ++i) {
CHECK_ALIVE(VisitForValue(exprs->at(i), flag));
}
}
bool HOptimizedGraphBuilder::BuildGraph() {
if (IsDerivedConstructor(current_info()->literal()->kind())) {
Bailout(kSuperReference);
return false;
}
DeclarationScope* scope = current_info()->scope();
SetUpScope(scope);
// Add an edge to the body entry. This is warty: the graph's start
// environment will be used by the Lithium translation as the initial
// environment on graph entry, but it has now been mutated by the
// Hydrogen translation of the instructions in the start block. This
// environment uses values which have not been defined yet. These
// Hydrogen instructions will then be replayed by the Lithium
// translation, so they cannot have an environment effect. The edge to
// the body's entry block (along with some special logic for the start
// block in HInstruction::InsertAfter) seals the start block from
// getting unwanted instructions inserted.
//
// TODO(kmillikin): Fix this. Stop mutating the initial environment.
// Make the Hydrogen instructions in the initial block into Hydrogen
// values (but not instructions), present in the initial environment and
// not replayed by the Lithium translation.
HEnvironment* initial_env = environment()->CopyWithoutHistory();
HBasicBlock* body_entry = CreateBasicBlock(initial_env);
Goto(body_entry);
body_entry->SetJoinId(BailoutId::FunctionEntry());
set_current_block(body_entry);
VisitDeclarations(scope->declarations());
Add<HSimulate>(BailoutId::Declarations());
Add<HStackCheck>(HStackCheck::kFunctionEntry);
VisitStatements(current_info()->literal()->body());
if (HasStackOverflow()) return false;
if (current_block() != NULL) {
Add<HReturn>(graph()->GetConstantUndefined());
set_current_block(NULL);
}
// If the checksum of the number of type info changes is the same as the
// last time this function was compiled, then this recompile is likely not
// due to missing/inadequate type feedback, but rather too aggressive
// optimization. Disable optimistic LICM in that case.
Handle<Code> unoptimized_code(current_info()->shared_info()->code());
DCHECK(unoptimized_code->kind() == Code::FUNCTION);
Handle<TypeFeedbackInfo> type_info(
TypeFeedbackInfo::cast(unoptimized_code->type_feedback_info()));
int checksum = type_info->own_type_change_checksum();
int composite_checksum = graph()->update_type_change_checksum(checksum);
graph()->set_use_optimistic_licm(
!type_info->matches_inlined_type_change_checksum(composite_checksum));
type_info->set_inlined_type_change_checksum(composite_checksum);
// Set this predicate early to avoid handle deref during graph optimization.
graph()->set_allow_code_motion(
current_info()->IsStub() ||
current_info()->shared_info()->deopt_count() + 1 < FLAG_max_deopt_count);
// Perform any necessary OSR-specific cleanups or changes to the graph.
osr()->FinishGraph();
return true;
}
bool HGraph::Optimize(BailoutReason* bailout_reason) {
OrderBlocks();
AssignDominators();
// We need to create a HConstant "zero" now so that GVN will fold every
// zero-valued constant in the graph together.
// The constant is needed to make idef-based bounds check work: the pass
// evaluates relations with "zero" and that zero cannot be created after GVN.
GetConstant0();
#ifdef DEBUG
// Do a full verify after building the graph and computing dominators.
Verify(true);
#endif
if (FLAG_analyze_environment_liveness && maximum_environment_size() != 0) {
Run<HEnvironmentLivenessAnalysisPhase>();
}
if (!CheckConstPhiUses()) {
*bailout_reason = kUnsupportedPhiUseOfConstVariable;
return false;
}
Run<HRedundantPhiEliminationPhase>();
if (!CheckArgumentsPhiUses()) {
*bailout_reason = kUnsupportedPhiUseOfArguments;
return false;
}
// Find and mark unreachable code to simplify optimizations, especially gvn,
// where unreachable code could unnecessarily defeat LICM.
Run<HMarkUnreachableBlocksPhase>();
if (FLAG_dead_code_elimination) Run<HDeadCodeEliminationPhase>();
if (FLAG_use_escape_analysis) Run<HEscapeAnalysisPhase>();
if (FLAG_load_elimination) Run<HLoadEliminationPhase>();
CollectPhis();
if (has_osr()) osr()->FinishOsrValues();
Run<HInferRepresentationPhase>();
// Remove HSimulate instructions that have turned out not to be needed
// after all by folding them into the following HSimulate.
// This must happen after inferring representations.
Run<HMergeRemovableSimulatesPhase>();
Run<HRepresentationChangesPhase>();
Run<HInferTypesPhase>();
// Must be performed before canonicalization to ensure that Canonicalize
// will not remove semantically meaningful ToInt32 operations e.g. BIT_OR with
// zero.
Run<HUint32AnalysisPhase>();
if (FLAG_use_canonicalizing) Run<HCanonicalizePhase>();
if (FLAG_use_gvn) Run<HGlobalValueNumberingPhase>();
if (FLAG_check_elimination) Run<HCheckEliminationPhase>();
if (FLAG_store_elimination) Run<HStoreEliminationPhase>();
Run<HRangeAnalysisPhase>();
// Eliminate redundant stack checks on backwards branches.
Run<HStackCheckEliminationPhase>();
if (FLAG_array_bounds_checks_elimination) Run<HBoundsCheckEliminationPhase>();
if (FLAG_array_index_dehoisting) Run<HDehoistIndexComputationsPhase>();
if (FLAG_dead_code_elimination) Run<HDeadCodeEliminationPhase>();
RestoreActualValues();
// Find unreachable code a second time, GVN and other optimizations may have
// made blocks unreachable that were previously reachable.
Run<HMarkUnreachableBlocksPhase>();
return true;
}
void HGraph::RestoreActualValues() {
HPhase phase("H_Restore actual values", this);
for (int block_index = 0; block_index < blocks()->length(); block_index++) {
HBasicBlock* block = blocks()->at(block_index);
#ifdef DEBUG
for (int i = 0; i < block->phis()->length(); i++) {
HPhi* phi = block->phis()->at(i);
DCHECK(phi->ActualValue() == phi);
}
#endif
for (HInstructionIterator it(block); !it.Done(); it.Advance()) {
HInstruction* instruction = it.Current();
if (instruction->ActualValue() == instruction) continue;
if (instruction->CheckFlag(HValue::kIsDead)) {
// The instruction was marked as deleted but left in the graph
// as a control flow dependency point for subsequent
// instructions.
instruction->DeleteAndReplaceWith(instruction->ActualValue());
} else {
DCHECK(instruction->IsInformativeDefinition());
if (instruction->IsPurelyInformativeDefinition()) {
instruction->DeleteAndReplaceWith(instruction->RedefinedOperand());
} else {
instruction->ReplaceAllUsesWith(instruction->ActualValue());
}
}
}
}
}
void HOptimizedGraphBuilder::PushArgumentsFromEnvironment(int count) {
ZoneList<HValue*> arguments(count, zone());
for (int i = 0; i < count; ++i) {
arguments.Add(Pop(), zone());
}
HPushArguments* push_args = New<HPushArguments>();
while (!arguments.is_empty()) {
push_args->AddInput(arguments.RemoveLast());
}
AddInstruction(push_args);
}
template <class Instruction>
HInstruction* HOptimizedGraphBuilder::PreProcessCall(Instruction* call) {
PushArgumentsFromEnvironment(call->argument_count());
return call;
}
void HOptimizedGraphBuilder::SetUpScope(DeclarationScope* scope) {
HEnvironment* prolog_env = environment();
int parameter_count = environment()->parameter_count();
ZoneList<HValue*> parameters(parameter_count, zone());
for (int i = 0; i < parameter_count; ++i) {
HInstruction* parameter = Add<HParameter>(static_cast<unsigned>(i));
parameters.Add(parameter, zone());
environment()->Bind(i, parameter);
}
HConstant* undefined_constant = graph()->GetConstantUndefined();
// Initialize specials and locals to undefined.
for (int i = parameter_count + 1; i < environment()->length(); ++i) {
environment()->Bind(i, undefined_constant);
}
Add<HPrologue>();
HEnvironment* initial_env = environment()->CopyWithoutHistory();
HBasicBlock* body_entry = CreateBasicBlock(initial_env);
GotoNoSimulate(body_entry);
set_current_block(body_entry);
// Initialize context of prolog environment to undefined.
prolog_env->BindContext(undefined_constant);
// First special is HContext.
HInstruction* context = Add<HContext>();
environment()->BindContext(context);
// Create an arguments object containing the initial parameters. Set the
// initial values of parameters including "this" having parameter index 0.
DCHECK_EQ(scope->num_parameters() + 1, parameter_count);
HArgumentsObject* arguments_object = New<HArgumentsObject>(parameter_count);
for (int i = 0; i < parameter_count; ++i) {
HValue* parameter = parameters.at(i);
arguments_object->AddArgument(parameter, zone());
}
AddInstruction(arguments_object);
// Handle the arguments and arguments shadow variables specially (they do
// not have declarations).
if (scope->arguments() != NULL) {
environment()->Bind(scope->arguments(), arguments_object);
}
if (scope->rest_parameter() != nullptr) {
return Bailout(kRestParameter);
}
if (scope->this_function_var() != nullptr ||
scope->new_target_var() != nullptr) {
return Bailout(kSuperReference);
}
// Trace the call.
if (FLAG_trace && top_info()->IsOptimizing()) {
Add<HCallRuntime>(Runtime::FunctionForId(Runtime::kTraceEnter), 0);
}
}
void HOptimizedGraphBuilder::VisitStatements(ZoneList<Statement*>* statements) {
for (int i = 0; i < statements->length(); i++) {
Statement* stmt = statements->at(i);
CHECK_ALIVE(Visit(stmt));
if (stmt->IsJump()) break;
}
}
void HOptimizedGraphBuilder::VisitBlock(Block* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
Scope* outer_scope = scope();
Scope* scope = stmt->scope();
BreakAndContinueInfo break_info(stmt, outer_scope);
{ BreakAndContinueScope push(&break_info, this);
if (scope != NULL) {
if (scope->NeedsContext()) {
// Load the function object.
DeclarationScope* declaration_scope = scope->GetDeclarationScope();
HInstruction* function;
HValue* outer_context = environment()->context();
if (declaration_scope->is_script_scope() ||
declaration_scope->is_eval_scope()) {
function = new (zone())
HLoadContextSlot(outer_context, Context::CLOSURE_INDEX,
HLoadContextSlot::kNoCheck);
} else {
function = New<HThisFunction>();
}
AddInstruction(function);
// Allocate a block context and store it to the stack frame.
HValue* scope_info = Add<HConstant>(scope->scope_info());
Add<HPushArguments>(scope_info, function);
HInstruction* inner_context = Add<HCallRuntime>(
Runtime::FunctionForId(Runtime::kPushBlockContext), 2);
inner_context->SetFlag(HValue::kHasNoObservableSideEffects);
set_scope(scope);
environment()->BindContext(inner_context);
}
VisitDeclarations(scope->declarations());
AddSimulate(stmt->DeclsId(), REMOVABLE_SIMULATE);
}
CHECK_BAILOUT(VisitStatements(stmt->statements()));
}
set_scope(outer_scope);
if (scope != NULL && current_block() != NULL &&
scope->ContextLocalCount() > 0) {
HValue* inner_context = environment()->context();
HValue* outer_context = Add<HLoadNamedField>(
inner_context, nullptr,
HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
environment()->BindContext(outer_context);
}
HBasicBlock* break_block = break_info.break_block();
if (break_block != NULL) {
if (current_block() != NULL) Goto(break_block);
break_block->SetJoinId(stmt->ExitId());
set_current_block(break_block);
}
}
void HOptimizedGraphBuilder::VisitExpressionStatement(
ExpressionStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
VisitForEffect(stmt->expression());
}
void HOptimizedGraphBuilder::VisitEmptyStatement(EmptyStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
}
void HOptimizedGraphBuilder::VisitSloppyBlockFunctionStatement(
SloppyBlockFunctionStatement* stmt) {
Visit(stmt->statement());
}
void HOptimizedGraphBuilder::VisitIfStatement(IfStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (stmt->condition()->ToBooleanIsTrue()) {
Add<HSimulate>(stmt->ThenId());
Visit(stmt->then_statement());
} else if (stmt->condition()->ToBooleanIsFalse()) {
Add<HSimulate>(stmt->ElseId());
Visit(stmt->else_statement());
} else {
HBasicBlock* cond_true = graph()->CreateBasicBlock();
HBasicBlock* cond_false = graph()->CreateBasicBlock();
CHECK_BAILOUT(VisitForControl(stmt->condition(), cond_true, cond_false));
// Technically, we should be able to handle the case when one side of
// the test is not connected, but this can trip up liveness analysis
// if we did not fully connect the test context based on some optimistic
// assumption. If such an assumption was violated, we would end up with
// an environment with optimized-out values. So we should always
// conservatively connect the test context.
CHECK(cond_true->HasPredecessor());
CHECK(cond_false->HasPredecessor());
cond_true->SetJoinId(stmt->ThenId());
set_current_block(cond_true);
CHECK_BAILOUT(Visit(stmt->then_statement()));
cond_true = current_block();
cond_false->SetJoinId(stmt->ElseId());
set_current_block(cond_false);
CHECK_BAILOUT(Visit(stmt->else_statement()));
cond_false = current_block();
HBasicBlock* join = CreateJoin(cond_true, cond_false, stmt->IfId());
set_current_block(join);
}
}
HBasicBlock* HOptimizedGraphBuilder::BreakAndContinueScope::Get(
BreakableStatement* stmt,
BreakType type,
Scope** scope,
int* drop_extra) {
*drop_extra = 0;
BreakAndContinueScope* current = this;
while (current != NULL && current->info()->target() != stmt) {
*drop_extra += current->info()->drop_extra();
current = current->next();
}
DCHECK(current != NULL); // Always found (unless stack is malformed).
*scope = current->info()->scope();
if (type == BREAK) {
*drop_extra += current->info()->drop_extra();
}
HBasicBlock* block = NULL;
switch (type) {
case BREAK:
block = current->info()->break_block();
if (block == NULL) {
block = current->owner()->graph()->CreateBasicBlock();
current->info()->set_break_block(block);
}
break;
case CONTINUE:
block = current->info()->continue_block();
if (block == NULL) {
block = current->owner()->graph()->CreateBasicBlock();
current->info()->set_continue_block(block);
}
break;
}
return block;
}
void HOptimizedGraphBuilder::VisitContinueStatement(
ContinueStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (function_state()->IsInsideDoExpressionScope()) {
return Bailout(kDoExpressionUnmodelable);
}
Scope* outer_scope = NULL;
Scope* inner_scope = scope();
int drop_extra = 0;
HBasicBlock* continue_block = break_scope()->Get(
stmt->target(), BreakAndContinueScope::CONTINUE,
&outer_scope, &drop_extra);
HValue* context = environment()->context();
Drop(drop_extra);
int context_pop_count = inner_scope->ContextChainLength(outer_scope);
if (context_pop_count > 0) {
while (context_pop_count-- > 0) {
HInstruction* context_instruction = Add<HLoadNamedField>(
context, nullptr,
HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
context = context_instruction;
}
environment()->BindContext(context);
}
Goto(continue_block);
set_current_block(NULL);
}
void HOptimizedGraphBuilder::VisitBreakStatement(BreakStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (function_state()->IsInsideDoExpressionScope()) {
return Bailout(kDoExpressionUnmodelable);
}
Scope* outer_scope = NULL;
Scope* inner_scope = scope();
int drop_extra = 0;
HBasicBlock* break_block = break_scope()->Get(
stmt->target(), BreakAndContinueScope::BREAK,
&outer_scope, &drop_extra);
HValue* context = environment()->context();
Drop(drop_extra);
int context_pop_count = inner_scope->ContextChainLength(outer_scope);
if (context_pop_count > 0) {
while (context_pop_count-- > 0) {
HInstruction* context_instruction = Add<HLoadNamedField>(
context, nullptr,
HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
context = context_instruction;
}
environment()->BindContext(context);
}
Goto(break_block);
set_current_block(NULL);
}
void HOptimizedGraphBuilder::VisitReturnStatement(ReturnStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
FunctionState* state = function_state();
AstContext* context = call_context();
if (context == NULL) {
// Not an inlined return, so an actual one.
CHECK_ALIVE(VisitForValue(stmt->expression()));
HValue* result = environment()->Pop();
Add<HReturn>(result);
} else if (state->inlining_kind() == CONSTRUCT_CALL_RETURN) {
// Return from an inlined construct call. In a test context the return value
// will always evaluate to true, in a value context the return value needs
// to be a JSObject.
if (context->IsTest()) {
CHECK_ALIVE(VisitForEffect(stmt->expression()));
context->ReturnValue(graph()->GetConstantTrue());
} else if (context->IsEffect()) {
CHECK_ALIVE(VisitForEffect(stmt->expression()));
Goto(function_return(), state);
} else {
DCHECK(context->IsValue());
CHECK_ALIVE(VisitForValue(stmt->expression()));
HValue* return_value = Pop();
HValue* receiver = environment()->arguments_environment()->Lookup(0);
HHasInstanceTypeAndBranch* typecheck =
New<HHasInstanceTypeAndBranch>(return_value,
FIRST_JS_RECEIVER_TYPE,
LAST_JS_RECEIVER_TYPE);
HBasicBlock* if_spec_object = graph()->CreateBasicBlock();
HBasicBlock* not_spec_object = graph()->CreateBasicBlock();
typecheck->SetSuccessorAt(0, if_spec_object);
typecheck->SetSuccessorAt(1, not_spec_object);
FinishCurrentBlock(typecheck);
AddLeaveInlined(if_spec_object, return_value, state);
AddLeaveInlined(not_spec_object, receiver, state);
}
} else if (state->inlining_kind() == SETTER_CALL_RETURN) {
// Return from an inlined setter call. The returned value is never used, the
// value of an assignment is always the value of the RHS of the assignment.
CHECK_ALIVE(VisitForEffect(stmt->expression()));
if (context->IsTest()) {
HValue* rhs = environment()->arguments_environment()->Lookup(1);
context->ReturnValue(rhs);
} else if (context->IsEffect()) {
Goto(function_return(), state);
} else {
DCHECK(context->IsValue());
HValue* rhs = environment()->arguments_environment()->Lookup(1);
AddLeaveInlined(rhs, state);
}
} else {
// Return from a normal inlined function. Visit the subexpression in the
// expression context of the call.
if (context->IsTest()) {
TestContext* test = TestContext::cast(context);
VisitForControl(stmt->expression(), test->if_true(), test->if_false());
} else if (context->IsEffect()) {
// Visit in value context and ignore the result. This is needed to keep
// environment in sync with full-codegen since some visitors (e.g.
// VisitCountOperation) use the operand stack differently depending on
// context.
CHECK_ALIVE(VisitForValue(stmt->expression()));
Pop();
Goto(function_return(), state);
} else {
DCHECK(context->IsValue());
CHECK_ALIVE(VisitForValue(stmt->expression()));
AddLeaveInlined(Pop(), state);
}
}
set_current_block(NULL);
}
void HOptimizedGraphBuilder::VisitWithStatement(WithStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kWithStatement);
}
void HOptimizedGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
ZoneList<CaseClause*>* clauses = stmt->cases();
int clause_count = clauses->length();
ZoneList<HBasicBlock*> body_blocks(clause_count, zone());
CHECK_ALIVE(VisitForValue(stmt->tag()));
Add<HSimulate>(stmt->EntryId());
HValue* tag_value = Top();
AstType* tag_type = bounds_.get(stmt->tag()).lower;
// 1. Build all the tests, with dangling true branches
BailoutId default_id = BailoutId::None();
for (int i = 0; i < clause_count; ++i) {
CaseClause* clause = clauses->at(i);
if (clause->is_default()) {
body_blocks.Add(NULL, zone());
if (default_id.IsNone()) default_id = clause->EntryId();
continue;
}
// Generate a compare and branch.
CHECK_BAILOUT(VisitForValue(clause->label()));
if (current_block() == NULL) return Bailout(kUnsupportedSwitchStatement);
HValue* label_value = Pop();
AstType* label_type = bounds_.get(clause->label()).lower;
AstType* combined_type = clause->compare_type();
HControlInstruction* compare = BuildCompareInstruction(
Token::EQ_STRICT, tag_value, label_value, tag_type, label_type,
combined_type,
ScriptPositionToSourcePosition(stmt->tag()->position()),
ScriptPositionToSourcePosition(clause->label()->position()),
PUSH_BEFORE_SIMULATE, clause->id());
HBasicBlock* next_test_block = graph()->CreateBasicBlock();
HBasicBlock* body_block = graph()->CreateBasicBlock();
body_blocks.Add(body_block, zone());
compare->SetSuccessorAt(0, body_block);
compare->SetSuccessorAt(1, next_test_block);
FinishCurrentBlock(compare);
set_current_block(body_block);
Drop(1); // tag_value
set_current_block(next_test_block);
}
// Save the current block to use for the default or to join with the
// exit.
HBasicBlock* last_block = current_block();
Drop(1); // tag_value
// 2. Loop over the clauses and the linked list of tests in lockstep,
// translating the clause bodies.
HBasicBlock* fall_through_block = NULL;
BreakAndContinueInfo break_info(stmt, scope());
{ BreakAndContinueScope push(&break_info, this);
for (int i = 0; i < clause_count; ++i) {
CaseClause* clause = clauses->at(i);
// Identify the block where normal (non-fall-through) control flow
// goes to.
HBasicBlock* normal_block = NULL;
if (clause->is_default()) {
if (last_block == NULL) continue;
normal_block = last_block;
last_block = NULL; // Cleared to indicate we've handled it.
} else {
normal_block = body_blocks[i];
}
if (fall_through_block == NULL) {
set_current_block(normal_block);
} else {
HBasicBlock* join = CreateJoin(fall_through_block,
normal_block,
clause->EntryId());
set_current_block(join);
}
CHECK_BAILOUT(VisitStatements(clause->statements()));
fall_through_block = current_block();
}
}
// Create an up-to-3-way join. Use the break block if it exists since
// it's already a join block.
HBasicBlock* break_block = break_info.break_block();
if (break_block == NULL) {
set_current_block(CreateJoin(fall_through_block,
last_block,
stmt->ExitId()));
} else {
if (fall_through_block != NULL) Goto(fall_through_block, break_block);
if (last_block != NULL) Goto(last_block, break_block);
break_block->SetJoinId(stmt->ExitId());
set_current_block(break_block);
}
}
void HOptimizedGraphBuilder::VisitLoopBody(IterationStatement* stmt,
BailoutId stack_check_id,
HBasicBlock* loop_entry) {
Add<HSimulate>(stack_check_id);
HStackCheck* stack_check =
HStackCheck::cast(Add<HStackCheck>(HStackCheck::kBackwardsBranch));
DCHECK(loop_entry->IsLoopHeader());
loop_entry->loop_information()->set_stack_check(stack_check);
CHECK_BAILOUT(Visit(stmt->body()));
}
void HOptimizedGraphBuilder::VisitDoWhileStatement(DoWhileStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
DCHECK(current_block() != NULL);
HBasicBlock* loop_entry = BuildLoopEntry(stmt);
BreakAndContinueInfo break_info(stmt, scope());
{
BreakAndContinueScope push(&break_info, this);
CHECK_BAILOUT(VisitLoopBody(stmt, stmt->StackCheckId(), loop_entry));
}
HBasicBlock* body_exit = JoinContinue(
stmt, stmt->ContinueId(), current_block(), break_info.continue_block());
HBasicBlock* loop_successor = NULL;
if (body_exit != NULL) {
set_current_block(body_exit);
loop_successor = graph()->CreateBasicBlock();
if (stmt->cond()->ToBooleanIsFalse()) {
loop_entry->loop_information()->stack_check()->Eliminate();
Goto(loop_successor);
body_exit = NULL;
} else {
// The block for a true condition, the actual predecessor block of the
// back edge.
body_exit = graph()->CreateBasicBlock();
CHECK_BAILOUT(VisitForControl(stmt->cond(), body_exit, loop_successor));
}
if (body_exit != NULL && body_exit->HasPredecessor()) {
body_exit->SetJoinId(stmt->BackEdgeId());
} else {
body_exit = NULL;
}
if (loop_successor->HasPredecessor()) {
loop_successor->SetJoinId(stmt->ExitId());
} else {
loop_successor = NULL;
}
}
HBasicBlock* loop_exit = CreateLoop(stmt,
loop_entry,
body_exit,
loop_successor,
break_info.break_block());
set_current_block(loop_exit);
}
void HOptimizedGraphBuilder::VisitWhileStatement(WhileStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
DCHECK(current_block() != NULL);
HBasicBlock* loop_entry = BuildLoopEntry(stmt);
// If the condition is constant true, do not generate a branch.
HBasicBlock* loop_successor = NULL;
HBasicBlock* body_entry = graph()->CreateBasicBlock();
loop_successor = graph()->CreateBasicBlock();
CHECK_BAILOUT(VisitForControl(stmt->cond(), body_entry, loop_successor));
if (body_entry->HasPredecessor()) {
body_entry->SetJoinId(stmt->BodyId());
set_current_block(body_entry);
}
if (loop_successor->HasPredecessor()) {
loop_successor->SetJoinId(stmt->ExitId());
} else {
loop_successor = NULL;
}
BreakAndContinueInfo break_info(stmt, scope());
if (current_block() != NULL) {
BreakAndContinueScope push(&break_info, this);
CHECK_BAILOUT(VisitLoopBody(stmt, stmt->StackCheckId(), loop_entry));
}
HBasicBlock* body_exit = JoinContinue(
stmt, stmt->ContinueId(), current_block(), break_info.continue_block());
HBasicBlock* loop_exit = CreateLoop(stmt,
loop_entry,
body_exit,
loop_successor,
break_info.break_block());
set_current_block(loop_exit);
}
void HOptimizedGraphBuilder::VisitForStatement(ForStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (stmt->init() != NULL) {
CHECK_ALIVE(Visit(stmt->init()));
}
DCHECK(current_block() != NULL);
HBasicBlock* loop_entry = BuildLoopEntry(stmt);
HBasicBlock* loop_successor = graph()->CreateBasicBlock();
HBasicBlock* body_entry = graph()->CreateBasicBlock();
if (stmt->cond() != NULL) {
CHECK_BAILOUT(VisitForControl(stmt->cond(), body_entry, loop_successor));
if (body_entry->HasPredecessor()) {
body_entry->SetJoinId(stmt->BodyId());
set_current_block(body_entry);
}
if (loop_successor->HasPredecessor()) {
loop_successor->SetJoinId(stmt->ExitId());
} else {
loop_successor = NULL;
}
} else {
// Create dummy control flow so that variable liveness analysis
// produces teh correct result.
HControlInstruction* branch = New<HBranch>(graph()->GetConstantTrue());
branch->SetSuccessorAt(0, body_entry);
branch->SetSuccessorAt(1, loop_successor);
FinishCurrentBlock(branch);
set_current_block(body_entry);
}
BreakAndContinueInfo break_info(stmt, scope());
if (current_block() != NULL) {
BreakAndContinueScope push(&break_info, this);
CHECK_BAILOUT(VisitLoopBody(stmt, stmt->StackCheckId(), loop_entry));
}
HBasicBlock* body_exit = JoinContinue(
stmt, stmt->ContinueId(), current_block(), break_info.continue_block());
if (stmt->next() != NULL && body_exit != NULL) {
set_current_block(body_exit);
CHECK_BAILOUT(Visit(stmt->next()));
body_exit = current_block();
}
HBasicBlock* loop_exit = CreateLoop(stmt,
loop_entry,
body_exit,
loop_successor,
break_info.break_block());
set_current_block(loop_exit);
}
void HOptimizedGraphBuilder::VisitForInStatement(ForInStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!stmt->each()->IsVariableProxy() ||
!stmt->each()->AsVariableProxy()->var()->IsStackLocal()) {
return Bailout(kForInStatementWithNonLocalEachVariable);
}
Variable* each_var = stmt->each()->AsVariableProxy()->var();
CHECK_ALIVE(VisitForValue(stmt->enumerable()));
HValue* enumerable = Top(); // Leave enumerable at the top.
IfBuilder if_undefined_or_null(this);
if_undefined_or_null.If<HCompareObjectEqAndBranch>(
enumerable, graph()->GetConstantUndefined());
if_undefined_or_null.Or();
if_undefined_or_null.If<HCompareObjectEqAndBranch>(
enumerable, graph()->GetConstantNull());
if_undefined_or_null.ThenDeopt(DeoptimizeReason::kUndefinedOrNullInForIn);
if_undefined_or_null.End();
BuildForInBody(stmt, each_var, enumerable);
}
void HOptimizedGraphBuilder::BuildForInBody(ForInStatement* stmt,
Variable* each_var,
HValue* enumerable) {
Handle<Map> meta_map = isolate()->factory()->meta_map();
bool fast = stmt->for_in_type() == ForInStatement::FAST_FOR_IN;
BuildCheckHeapObject(enumerable);
Add<HCheckInstanceType>(enumerable, HCheckInstanceType::IS_JS_RECEIVER);
Add<HSimulate>(stmt->ToObjectId());
if (fast) {
HForInPrepareMap* map = Add<HForInPrepareMap>(enumerable);
Push(map);
Add<HSimulate>(stmt->EnumId());
Drop(1);
Add<HCheckMaps>(map, meta_map);
HForInCacheArray* array = Add<HForInCacheArray>(
enumerable, map, DescriptorArray::kEnumCacheBridgeCacheIndex);
HValue* enum_length = BuildEnumLength(map);
HForInCacheArray* index_cache = Add<HForInCacheArray>(
enumerable, map, DescriptorArray::kEnumCacheBridgeIndicesCacheIndex);
array->set_index_cache(index_cache);
Push(map);
Push(array);
Push(enum_length);
Add<HSimulate>(stmt->PrepareId());
} else {
Runtime::FunctionId function_id = Runtime::kForInEnumerate;
Add<HPushArguments>(enumerable);
HCallRuntime* array =
Add<HCallRuntime>(Runtime::FunctionForId(function_id), 1);
Push(array);
Add<HSimulate>(stmt->EnumId());
Drop(1);
IfBuilder if_fast(this);
if_fast.If<HCompareMap>(array, meta_map);
if_fast.Then();
{
HValue* cache_map = array;
HForInCacheArray* cache = Add<HForInCacheArray>(
enumerable, cache_map, DescriptorArray::kEnumCacheBridgeCacheIndex);
HValue* enum_length = BuildEnumLength(cache_map);
Push(cache_map);
Push(cache);
Push(enum_length);
Add<HSimulate>(stmt->PrepareId(), FIXED_SIMULATE);
}
if_fast.Else();
{
Push(graph()->GetConstant1());
Push(array);
Push(AddLoadFixedArrayLength(array));
Add<HSimulate>(stmt->PrepareId(), FIXED_SIMULATE);
}
}
Push(graph()->GetConstant0());
HBasicBlock* loop_entry = BuildLoopEntry(stmt);
// Reload the values to ensure we have up-to-date values inside of the loop.
// This is relevant especially for OSR where the values don't come from the
// computation above, but from the OSR entry block.
HValue* index = environment()->ExpressionStackAt(0);
HValue* limit = environment()->ExpressionStackAt(1);
HValue* array = environment()->ExpressionStackAt(2);
HValue* type = environment()->ExpressionStackAt(3);
enumerable = environment()->ExpressionStackAt(4);
// Check that we still have more keys.
HCompareNumericAndBranch* compare_index =
New<HCompareNumericAndBranch>(index, limit, Token::LT);
compare_index->set_observed_input_representation(
Representation::Smi(), Representation::Smi());
HBasicBlock* loop_body = graph()->CreateBasicBlock();
HBasicBlock* loop_successor = graph()->CreateBasicBlock();
compare_index->SetSuccessorAt(0, loop_body);
compare_index->SetSuccessorAt(1, loop_successor);
FinishCurrentBlock(compare_index);
set_current_block(loop_successor);
Drop(5);
set_current_block(loop_body);
// Compute the next enumerated value.
HValue* key = Add<HLoadKeyed>(array, index, index, nullptr, FAST_ELEMENTS);
HBasicBlock* continue_block = nullptr;
if (fast) {
// Check if expected map still matches that of the enumerable.
Add<HCheckMapValue>(enumerable, type);
Add<HSimulate>(stmt->FilterId());
} else {
// We need the continue block here to be able to skip over invalidated keys.
continue_block = graph()->CreateBasicBlock();
// We cannot use the IfBuilder here, since we need to be able to jump
// over the loop body in case of undefined result from %ForInFilter,
// and the poor soul that is the IfBuilder get's really confused about
// such "advanced control flow requirements".
HBasicBlock* if_fast = graph()->CreateBasicBlock();
HBasicBlock* if_slow = graph()->CreateBasicBlock();
HBasicBlock* if_slow_pass = graph()->CreateBasicBlock();
HBasicBlock* if_slow_skip = graph()->CreateBasicBlock();
HBasicBlock* if_join = graph()->CreateBasicBlock();
// Check if expected map still matches that of the enumerable.
HValue* enumerable_map =
Add<HLoadNamedField>(enumerable, nullptr, HObjectAccess::ForMap());
FinishCurrentBlock(
New<HCompareObjectEqAndBranch>(enumerable_map, type, if_fast, if_slow));
set_current_block(if_fast);
{
// The enum cache for enumerable is still valid, no need to check key.
Push(key);
Goto(if_join);
}
set_current_block(if_slow);
{
Callable callable = CodeFactory::ForInFilter(isolate());
HValue* values[] = {key, enumerable};
HConstant* stub_value = Add<HConstant>(callable.code());
Push(Add<HCallWithDescriptor>(stub_value, 0, callable.descriptor(),
ArrayVector(values)));
Add<HSimulate>(stmt->FilterId());
FinishCurrentBlock(New<HCompareObjectEqAndBranch>(
Top(), graph()->GetConstantUndefined(), if_slow_skip, if_slow_pass));
}
set_current_block(if_slow_pass);
{ Goto(if_join); }
set_current_block(if_slow_skip);
{
// The key is no longer valid for enumerable, skip it.
Drop(1);
Goto(continue_block);
}
if_join->SetJoinId(stmt->FilterId());
set_current_block(if_join);
key = Pop();
}
Bind(each_var, key);
Add<HSimulate>(stmt->AssignmentId());
BreakAndContinueInfo break_info(stmt, scope(), 5);
break_info.set_continue_block(continue_block);
{
BreakAndContinueScope push(&break_info, this);
CHECK_BAILOUT(VisitLoopBody(stmt, stmt->StackCheckId(), loop_entry));
}
HBasicBlock* body_exit = JoinContinue(
stmt, stmt->IncrementId(), current_block(), break_info.continue_block());
if (body_exit != NULL) {
set_current_block(body_exit);
HValue* current_index = Pop();
HValue* increment =
AddUncasted<HAdd>(current_index, graph()->GetConstant1());
increment->ClearFlag(HValue::kCanOverflow);
Push(increment);
body_exit = current_block();
}
HBasicBlock* loop_exit = CreateLoop(stmt,
loop_entry,
body_exit,
loop_successor,
break_info.break_block());
set_current_block(loop_exit);
}
void HOptimizedGraphBuilder::VisitForOfStatement(ForOfStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kForOfStatement);
}
void HOptimizedGraphBuilder::VisitTryCatchStatement(TryCatchStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kTryCatchStatement);
}
void HOptimizedGraphBuilder::VisitTryFinallyStatement(
TryFinallyStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kTryFinallyStatement);
}
void HOptimizedGraphBuilder::VisitDebuggerStatement(DebuggerStatement* stmt) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kDebuggerStatement);
}
void HOptimizedGraphBuilder::VisitCaseClause(CaseClause* clause) {
UNREACHABLE();
}
void HOptimizedGraphBuilder::VisitFunctionLiteral(FunctionLiteral* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
Handle<SharedFunctionInfo> shared_info = Compiler::GetSharedFunctionInfo(
expr, current_info()->script(), top_info());
// We also have a stack overflow if the recursive compilation did.
if (HasStackOverflow()) return;
// Use the fast case closure allocation code that allocates in new
// space for nested functions that don't need pretenuring.
HConstant* shared_info_value = Add<HConstant>(shared_info);
HInstruction* instr;
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
HValue* vector_value = Add<HConstant>(vector);
int index = FeedbackVector::GetIndex(expr->LiteralFeedbackSlot());
HValue* index_value = Add<HConstant>(index);
if (!expr->pretenure()) {
Callable callable = CodeFactory::FastNewClosure(isolate());
HValue* values[] = {shared_info_value, vector_value, index_value};
HConstant* stub_value = Add<HConstant>(callable.code());
instr = New<HCallWithDescriptor>(stub_value, 0, callable.descriptor(),
ArrayVector(values));
} else {
Add<HPushArguments>(shared_info_value);
Add<HPushArguments>(vector_value);
Add<HPushArguments>(index_value);
Runtime::FunctionId function_id =
expr->pretenure() ? Runtime::kNewClosure_Tenured : Runtime::kNewClosure;
instr = New<HCallRuntime>(Runtime::FunctionForId(function_id), 3);
}
return ast_context()->ReturnInstruction(instr, expr->id());
}
void HOptimizedGraphBuilder::VisitClassLiteral(ClassLiteral* lit) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kClassLiteral);
}
void HOptimizedGraphBuilder::VisitNativeFunctionLiteral(
NativeFunctionLiteral* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kNativeFunctionLiteral);
}
void HOptimizedGraphBuilder::VisitDoExpression(DoExpression* expr) {
DoExpressionScope scope(this);
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
CHECK_ALIVE(VisitBlock(expr->block()));
Visit(expr->result());
}
void HOptimizedGraphBuilder::VisitConditional(Conditional* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
HBasicBlock* cond_true = graph()->CreateBasicBlock();
HBasicBlock* cond_false = graph()->CreateBasicBlock();
CHECK_BAILOUT(VisitForControl(expr->condition(), cond_true, cond_false));
// Visit the true and false subexpressions in the same AST context as the
// whole expression.
if (cond_true->HasPredecessor()) {
cond_true->SetJoinId(expr->ThenId());
set_current_block(cond_true);
CHECK_BAILOUT(Visit(expr->then_expression()));
cond_true = current_block();
} else {
cond_true = NULL;
}
if (cond_false->HasPredecessor()) {
cond_false->SetJoinId(expr->ElseId());
set_current_block(cond_false);
CHECK_BAILOUT(Visit(expr->else_expression()));
cond_false = current_block();
} else {
cond_false = NULL;
}
if (!ast_context()->IsTest()) {
HBasicBlock* join = CreateJoin(cond_true, cond_false, expr->id());
set_current_block(join);
if (join != NULL && !ast_context()->IsEffect()) {
return ast_context()->ReturnValue(Pop());
}
}
}
bool HOptimizedGraphBuilder::CanInlineGlobalPropertyAccess(
Variable* var, LookupIterator* it, PropertyAccessType access_type) {
if (var->is_this()) return false;
return CanInlineGlobalPropertyAccess(it, access_type);
}
bool HOptimizedGraphBuilder::CanInlineGlobalPropertyAccess(
LookupIterator* it, PropertyAccessType access_type) {
if (!current_info()->has_global_object()) {
return false;
}
switch (it->state()) {
case LookupIterator::ACCESSOR:
case LookupIterator::ACCESS_CHECK:
case LookupIterator::INTERCEPTOR:
case LookupIterator::INTEGER_INDEXED_EXOTIC:
case LookupIterator::NOT_FOUND:
return false;
case LookupIterator::DATA:
if (access_type == STORE && it->IsReadOnly()) return false;
if (!it->GetHolder<JSObject>()->IsJSGlobalObject()) return false;
return true;
case LookupIterator::JSPROXY:
case LookupIterator::TRANSITION:
UNREACHABLE();
}
UNREACHABLE();
}
HValue* HOptimizedGraphBuilder::BuildContextChainWalk(Variable* var) {
DCHECK(var->IsContextSlot());
HValue* context = environment()->context();
int length = scope()->ContextChainLength(var->scope());
while (length-- > 0) {
context = Add<HLoadNamedField>(
context, nullptr,
HObjectAccess::ForContextSlot(Context::PREVIOUS_INDEX));
}
return context;
}
void HOptimizedGraphBuilder::InlineGlobalPropertyLoad(LookupIterator* it,
BailoutId ast_id) {
Handle<PropertyCell> cell = it->GetPropertyCell();
top_info()->dependencies()->AssumePropertyCell(cell);
auto cell_type = it->property_details().cell_type();
if (cell_type == PropertyCellType::kConstant ||
cell_type == PropertyCellType::kUndefined) {
Handle<Object> constant_object(cell->value(), isolate());
if (constant_object->IsConsString()) {
constant_object = String::Flatten(Handle<String>::cast(constant_object));
}
HConstant* constant = New<HConstant>(constant_object);
return ast_context()->ReturnInstruction(constant, ast_id);
} else {
auto access = HObjectAccess::ForPropertyCellValue();
UniqueSet<Map>* field_maps = nullptr;
if (cell_type == PropertyCellType::kConstantType) {
switch (cell->GetConstantType()) {
case PropertyCellConstantType::kSmi:
access = access.WithRepresentation(Representation::Smi());
break;
case PropertyCellConstantType::kStableMap: {
// Check that the map really is stable. The heap object could
// have mutated without the cell updating state. In that case,
// make no promises about the loaded value except that it's a
// heap object.
access = access.WithRepresentation(Representation::HeapObject());
Handle<Map> map(HeapObject::cast(cell->value())->map());
if (map->is_stable()) {
field_maps = new (zone())
UniqueSet<Map>(Unique<Map>::CreateImmovable(map), zone());
}
break;
}
}
}
HConstant* cell_constant = Add<HConstant>(cell);
HLoadNamedField* instr;
if (field_maps == nullptr) {
instr = New<HLoadNamedField>(cell_constant, nullptr, access);
} else {
instr = New<HLoadNamedField>(cell_constant, nullptr, access, field_maps,
HType::HeapObject());
}
instr->ClearDependsOnFlag(kInobjectFields);
instr->SetDependsOnFlag(kGlobalVars);
return ast_context()->ReturnInstruction(instr, ast_id);
}
}
void HOptimizedGraphBuilder::VisitVariableProxy(VariableProxy* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
Variable* variable = expr->var();
switch (variable->location()) {
case VariableLocation::UNALLOCATED: {
if (IsLexicalVariableMode(variable->mode())) {
// TODO(rossberg): should this be an DCHECK?
return Bailout(kReferenceToGlobalLexicalVariable);
}
// Handle known global constants like 'undefined' specially to avoid a
// load from a global cell for them.
Handle<Object> constant_value =
isolate()->factory()->GlobalConstantFor(variable->name());
if (!constant_value.is_null()) {
HConstant* instr = New<HConstant>(constant_value);
return ast_context()->ReturnInstruction(instr, expr->id());
}
Handle<JSGlobalObject> global(current_info()->global_object());
// Lookup in script contexts.
{
Handle<ScriptContextTable> script_contexts(
global->native_context()->script_context_table());
ScriptContextTable::LookupResult lookup;
if (ScriptContextTable::Lookup(script_contexts, variable->name(),
&lookup)) {
Handle<Context> script_context = ScriptContextTable::GetContext(
script_contexts, lookup.context_index);
Handle<Object> current_value =
FixedArray::get(*script_context, lookup.slot_index, isolate());
// If the values is not the hole, it will stay initialized,
// so no need to generate a check.
if (current_value->IsTheHole(isolate())) {
return Bailout(kReferenceToUninitializedVariable);
}
HInstruction* result = New<HLoadNamedField>(
Add<HConstant>(script_context), nullptr,
HObjectAccess::ForContextSlot(lookup.slot_index));
return ast_context()->ReturnInstruction(result, expr->id());
}
}
LookupIterator it(global, variable->name(), LookupIterator::OWN);
it.TryLookupCachedProperty();
if (CanInlineGlobalPropertyAccess(variable, &it, LOAD)) {
InlineGlobalPropertyLoad(&it, expr->id());
return;
} else {
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
FeedbackSlot slot = expr->VariableFeedbackSlot();
DCHECK(vector->IsLoadGlobalIC(slot));
HValue* vector_value = Add<HConstant>(vector);
HValue* slot_value = Add<HConstant>(vector->GetIndex(slot));
Callable callable = CodeFactory::LoadGlobalICInOptimizedCode(
isolate(), ast_context()->typeof_mode());
HValue* stub = Add<HConstant>(callable.code());
HValue* name = Add<HConstant>(variable->name());
HValue* values[] = {name, slot_value, vector_value};
HCallWithDescriptor* instr = New<HCallWithDescriptor>(
Code::LOAD_GLOBAL_IC, stub, 0, callable.descriptor(),
ArrayVector(values));
return ast_context()->ReturnInstruction(instr, expr->id());
}
}
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL: {
HValue* value = LookupAndMakeLive(variable);
if (value == graph()->GetConstantHole()) {
DCHECK(IsDeclaredVariableMode(variable->mode()) &&
variable->mode() != VAR);
return Bailout(kReferenceToUninitializedVariable);
}
return ast_context()->ReturnValue(value);
}
case VariableLocation::CONTEXT: {
HValue* context = BuildContextChainWalk(variable);
HLoadContextSlot::Mode mode;
switch (variable->mode()) {
case LET:
case CONST:
mode = HLoadContextSlot::kCheckDeoptimize;
break;
default:
mode = HLoadContextSlot::kNoCheck;
break;
}
HLoadContextSlot* instr =
new(zone()) HLoadContextSlot(context, variable->index(), mode);
return ast_context()->ReturnInstruction(instr, expr->id());
}
case VariableLocation::LOOKUP:
return Bailout(kReferenceToAVariableWhichRequiresDynamicLookup);
case VariableLocation::MODULE:
UNREACHABLE();
}
}
void HOptimizedGraphBuilder::VisitLiteral(Literal* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
HConstant* instr = New<HConstant>(expr->value());
return ast_context()->ReturnInstruction(instr, expr->id());
}
void HOptimizedGraphBuilder::VisitRegExpLiteral(RegExpLiteral* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
Callable callable = CodeFactory::FastCloneRegExp(isolate());
int index = FeedbackVector::GetIndex(expr->literal_slot());
HValue* values[] = {AddThisFunction(), Add<HConstant>(index),
Add<HConstant>(expr->pattern()),
Add<HConstant>(expr->flags())};
HConstant* stub_value = Add<HConstant>(callable.code());
HInstruction* instr = New<HCallWithDescriptor>(
stub_value, 0, callable.descriptor(), ArrayVector(values));
return ast_context()->ReturnInstruction(instr, expr->id());
}
static bool CanInlinePropertyAccess(Handle<Map> map) {
if (map->instance_type() == HEAP_NUMBER_TYPE) return true;
if (map->instance_type() < FIRST_NONSTRING_TYPE) return true;
return map->IsJSObjectMap() && !map->is_dictionary_map() &&
!map->has_named_interceptor() &&
// TODO(verwaest): Whitelist contexts to which we have access.
!map->is_access_check_needed();
}
// Determines whether the given array or object literal boilerplate satisfies
// all limits to be considered for fast deep-copying and computes the total
// size of all objects that are part of the graph.
static bool IsFastLiteral(Handle<JSObject> boilerplate,
int max_depth,
int* max_properties) {
if (boilerplate->map()->is_deprecated() &&
!JSObject::TryMigrateInstance(boilerplate)) {
return false;
}
DCHECK(max_depth >= 0 && *max_properties >= 0);
if (max_depth == 0) return false;
Isolate* isolate = boilerplate->GetIsolate();
Handle<FixedArrayBase> elements(boilerplate->elements());
if (elements->length() > 0 &&
elements->map() != isolate->heap()->fixed_cow_array_map()) {
if (boilerplate->HasFastSmiOrObjectElements()) {
Handle<FixedArray> fast_elements = Handle<FixedArray>::cast(elements);
int length = elements->length();
for (int i = 0; i < length; i++) {
if ((*max_properties)-- == 0) return false;
Handle<Object> value(fast_elements->get(i), isolate);
if (value->IsJSObject()) {
Handle<JSObject> value_object = Handle<JSObject>::cast(value);
if (!IsFastLiteral(value_object,
max_depth - 1,
max_properties)) {
return false;
}
}
}
} else if (boilerplate->HasFastDoubleElements()) {
if (elements->Size() > kMaxRegularHeapObjectSize) return false;
} else {
return false;
}
}
Handle<FixedArray> properties(boilerplate->properties());
if (properties->length() > 0) {
return false;
} else {
Handle<DescriptorArray> descriptors(
boilerplate->map()->instance_descriptors());
int limit = boilerplate->map()->NumberOfOwnDescriptors();
for (int i = 0; i < limit; i++) {
PropertyDetails details = descriptors->GetDetails(i);
if (details.location() != kField) continue;
DCHECK_EQ(kData, details.kind());
if ((*max_properties)-- == 0) return false;
FieldIndex field_index = FieldIndex::ForDescriptor(boilerplate->map(), i);
if (boilerplate->IsUnboxedDoubleField(field_index)) continue;
Handle<Object> value(boilerplate->RawFastPropertyAt(field_index),
isolate);
if (value->IsJSObject()) {
Handle<JSObject> value_object = Handle<JSObject>::cast(value);
if (!IsFastLiteral(value_object,
max_depth - 1,
max_properties)) {
return false;
}
}
}
}
return true;
}
void HOptimizedGraphBuilder::VisitObjectLiteral(ObjectLiteral* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
Handle<JSFunction> closure = function_state()->compilation_info()->closure();
HInstruction* literal;
// Check whether to use fast or slow deep-copying for boilerplate.
int max_properties = kMaxFastLiteralProperties;
Handle<Object> literals_cell(
closure->feedback_vector()->Get(expr->literal_slot()), isolate());
Handle<AllocationSite> site;
Handle<JSObject> boilerplate;
if (!literals_cell->IsUndefined(isolate())) {
// Retrieve the boilerplate
site = Handle<AllocationSite>::cast(literals_cell);
boilerplate = Handle<JSObject>(JSObject::cast(site->transition_info()),
isolate());
}
if (!boilerplate.is_null() &&
IsFastLiteral(boilerplate, kMaxFastLiteralDepth, &max_properties)) {
AllocationSiteUsageContext site_context(isolate(), site, false);
site_context.EnterNewScope();
literal = BuildFastLiteral(boilerplate, &site_context);
site_context.ExitScope(site, boilerplate);
} else {
NoObservableSideEffectsScope no_effects(this);
Handle<BoilerplateDescription> constant_properties =
expr->GetOrBuildConstantProperties(isolate());
int literal_index = FeedbackVector::GetIndex(expr->literal_slot());
int flags = expr->ComputeFlags(true);
Add<HPushArguments>(AddThisFunction(), Add<HConstant>(literal_index),
Add<HConstant>(constant_properties),
Add<HConstant>(flags));
Runtime::FunctionId function_id = Runtime::kCreateObjectLiteral;
literal = Add<HCallRuntime>(Runtime::FunctionForId(function_id), 4);
}
// The object is expected in the bailout environment during computation
// of the property values and is the value of the entire expression.
Push(literal);
for (int i = 0; i < expr->properties()->length(); i++) {
ObjectLiteral::Property* property = expr->properties()->at(i);
if (property->is_computed_name()) return Bailout(kComputedPropertyName);
if (property->IsCompileTimeValue()) continue;
Literal* key = property->key()->AsLiteral();
Expression* value = property->value();
switch (property->kind()) {
case ObjectLiteral::Property::MATERIALIZED_LITERAL:
DCHECK(!CompileTimeValue::IsCompileTimeValue(value));
// Fall through.
case ObjectLiteral::Property::COMPUTED:
// It is safe to use [[Put]] here because the boilerplate already
// contains computed properties with an uninitialized value.
if (key->IsStringLiteral()) {
DCHECK(key->IsPropertyName());
if (property->emit_store()) {
CHECK_ALIVE(VisitForValue(value));
HValue* value = Pop();
Handle<Map> map = property->GetReceiverType();
Handle<String> name = key->AsPropertyName();
HValue* store;
FeedbackSlot slot = property->GetSlot();
if (map.is_null()) {
// If we don't know the monomorphic type, do a generic store.
CHECK_ALIVE(store = BuildNamedGeneric(STORE, NULL, slot, literal,
name, value));
} else {
PropertyAccessInfo info(this, STORE, map, name);
if (info.CanAccessMonomorphic()) {
HValue* checked_literal = Add<HCheckMaps>(literal, map);
DCHECK(!info.IsAccessorConstant());
info.MarkAsInitializingStore();
store = BuildMonomorphicAccess(
&info, literal, checked_literal, value,
BailoutId::None(), BailoutId::None());
DCHECK_NOT_NULL(store);
} else {
CHECK_ALIVE(store = BuildNamedGeneric(STORE, NULL, slot,
literal, name, value));
}
}
if (store->IsInstruction()) {
AddInstruction(HInstruction::cast(store));
}
DCHECK(store->HasObservableSideEffects());
Add<HSimulate>(key->id(), REMOVABLE_SIMULATE);
// Add [[HomeObject]] to function literals.
if (FunctionLiteral::NeedsHomeObject(property->value())) {
Handle<Symbol> sym = isolate()->factory()->home_object_symbol();
HInstruction* store_home = BuildNamedGeneric(
STORE, NULL, property->GetSlot(1), value, sym, literal);
AddInstruction(store_home);
DCHECK(store_home->HasObservableSideEffects());
Add<HSimulate>(property->value()->id(), REMOVABLE_SIMULATE);
}
} else {
CHECK_ALIVE(VisitForEffect(value));
}
break;
}
// Fall through.
case ObjectLiteral::Property::PROTOTYPE:
case ObjectLiteral::Property::SETTER:
case ObjectLiteral::Property::GETTER:
return Bailout(kObjectLiteralWithComplexProperty);
default: UNREACHABLE();
}
}
return ast_context()->ReturnValue(Pop());
}
void HOptimizedGraphBuilder::VisitArrayLiteral(ArrayLiteral* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
ZoneList<Expression*>* subexprs = expr->values();
int length = subexprs->length();
HInstruction* literal;
Handle<AllocationSite> site;
Handle<FeedbackVector> vector(environment()->closure()->feedback_vector(),
isolate());
Handle<Object> literals_cell(vector->Get(expr->literal_slot()), isolate());
Handle<JSObject> boilerplate_object;
if (!literals_cell->IsUndefined(isolate())) {
DCHECK(literals_cell->IsAllocationSite());
site = Handle<AllocationSite>::cast(literals_cell);
boilerplate_object = Handle<JSObject>(
JSObject::cast(site->transition_info()), isolate());
}
// Check whether to use fast or slow deep-copying for boilerplate.
int max_properties = kMaxFastLiteralProperties;
if (!boilerplate_object.is_null() &&
IsFastLiteral(boilerplate_object, kMaxFastLiteralDepth,
&max_properties)) {
DCHECK(site->SitePointsToLiteral());
AllocationSiteUsageContext site_context(isolate(), site, false);
site_context.EnterNewScope();
literal = BuildFastLiteral(boilerplate_object, &site_context);
site_context.ExitScope(site, boilerplate_object);
} else {
NoObservableSideEffectsScope no_effects(this);
Handle<ConstantElementsPair> constants =
expr->GetOrBuildConstantElements(isolate());
int literal_index = FeedbackVector::GetIndex(expr->literal_slot());
int flags = expr->ComputeFlags(true);
Add<HPushArguments>(AddThisFunction(), Add<HConstant>(literal_index),
Add<HConstant>(constants), Add<HConstant>(flags));
Runtime::FunctionId function_id = Runtime::kCreateArrayLiteral;
literal = Add<HCallRuntime>(Runtime::FunctionForId(function_id), 4);
// Register to deopt if the boilerplate ElementsKind changes.
if (!site.is_null()) {
top_info()->dependencies()->AssumeTransitionStable(site);
}
}
// The array is expected in the bailout environment during computation
// of the property values and is the value of the entire expression.
Push(literal);
HInstruction* elements = NULL;
for (int i = 0; i < length; i++) {
Expression* subexpr = subexprs->at(i);
DCHECK(!subexpr->IsSpread());
// If the subexpression is a literal or a simple materialized literal it
// is already set in the cloned array.
if (CompileTimeValue::IsCompileTimeValue(subexpr)) continue;
CHECK_ALIVE(VisitForValue(subexpr));
HValue* value = Pop();
if (!Smi::IsValid(i)) return Bailout(kNonSmiKeyInArrayLiteral);
elements = AddLoadElements(literal);
HValue* key = Add<HConstant>(i);
if (!boilerplate_object.is_null()) {
ElementsKind boilerplate_elements_kind =
boilerplate_object->GetElementsKind();
switch (boilerplate_elements_kind) {
case FAST_SMI_ELEMENTS:
case FAST_HOLEY_SMI_ELEMENTS:
case FAST_ELEMENTS:
case FAST_HOLEY_ELEMENTS:
case FAST_DOUBLE_ELEMENTS:
case FAST_HOLEY_DOUBLE_ELEMENTS: {
Add<HStoreKeyed>(elements, key, value, nullptr,
boilerplate_elements_kind);
break;
}
default:
UNREACHABLE();
break;
}
} else {
HInstruction* instr = BuildKeyedGeneric(
STORE, expr, expr->LiteralFeedbackSlot(), literal, key, value);
AddInstruction(instr);
}
Add<HSimulate>(expr->GetIdForElement(i));
}
return ast_context()->ReturnValue(Pop());
}
HCheckMaps* HOptimizedGraphBuilder::AddCheckMap(HValue* object,
Handle<Map> map) {
BuildCheckHeapObject(object);
return Add<HCheckMaps>(object, map);
}
HInstruction* HOptimizedGraphBuilder::BuildLoadNamedField(
PropertyAccessInfo* info,
HValue* checked_object) {
// Check if this is a load of an immutable or constant property.
if (checked_object->ActualValue()->IsConstant()) {
Handle<Object> object(
HConstant::cast(checked_object->ActualValue())->handle(isolate()));
if (object->IsJSObject()) {
LookupIterator it(object, info->name(),
LookupIterator::OWN_SKIP_INTERCEPTOR);
if (it.IsFound()) {
bool is_reaonly_non_configurable =
it.IsReadOnly() && !it.IsConfigurable();
if (is_reaonly_non_configurable ||
(FLAG_track_constant_fields && info->IsDataConstantField())) {
Handle<Object> value = JSReceiver::GetDataProperty(&it);
if (!is_reaonly_non_configurable) {
DCHECK(!it.is_dictionary_holder());
// Add dependency on the map that introduced the field.
Handle<Map> field_owner_map = it.GetFieldOwnerMap();
top_info()->dependencies()->AssumeFieldOwner(field_owner_map);
}
return New<HConstant>(value);
}
}
}
}
HObjectAccess access = info->access();
if (access.representation().IsDouble() &&
(!FLAG_unbox_double_fields || !access.IsInobject())) {
// Load the heap number.
checked_object = Add<HLoadNamedField>(
checked_object, nullptr,
access.WithRepresentation(Representation::Tagged()));
// Load the double value from it.
access = HObjectAccess::ForHeapNumberValue();
}
SmallMapList* map_list = info->field_maps();
if (map_list->length() == 0) {
return New<HLoadNamedField>(checked_object, checked_object, access);
}
UniqueSet<Map>* maps = new(zone()) UniqueSet<Map>(map_list->length(), zone());
for (int i = 0; i < map_list->length(); ++i) {
maps->Add(Unique<Map>::CreateImmovable(map_list->at(i)), zone());
}
return New<HLoadNamedField>(
checked_object, checked_object, access, maps, info->field_type());
}
HValue* HOptimizedGraphBuilder::BuildStoreNamedField(PropertyAccessInfo* info,
HValue* checked_object,
HValue* value) {
bool transition_to_field = info->IsTransition();
// TODO(verwaest): Move this logic into PropertyAccessInfo.
HObjectAccess field_access = info->access();
bool store_to_constant_field = FLAG_track_constant_fields &&
info->StoreMode() != INITIALIZING_STORE &&
info->IsDataConstantField();
HStoreNamedField *instr;
if (field_access.representation().IsDouble() &&
(!FLAG_unbox_double_fields || !field_access.IsInobject())) {
HObjectAccess heap_number_access =
field_access.WithRepresentation(Representation::Tagged());
if (transition_to_field) {
// The store requires a mutable HeapNumber to be allocated.
NoObservableSideEffectsScope no_side_effects(this);
HInstruction* heap_number_size = Add<HConstant>(HeapNumber::kSize);
// TODO(hpayer): Allocation site pretenuring support.
HInstruction* heap_number =
Add<HAllocate>(heap_number_size, HType::HeapObject(), NOT_TENURED,
MUTABLE_HEAP_NUMBER_TYPE, graph()->GetConstant0());
AddStoreMapConstant(
heap_number, isolate()->factory()->mutable_heap_number_map());
Add<HStoreNamedField>(heap_number, HObjectAccess::ForHeapNumberValue(),
value);
instr = New<HStoreNamedField>(checked_object->ActualValue(),
heap_number_access,
heap_number);
} else {
// Already holds a HeapNumber; load the box and write its value field.
HInstruction* heap_number =
Add<HLoadNamedField>(checked_object, nullptr, heap_number_access);
if (store_to_constant_field) {
// If the field is constant check that the value we are going to store
// matches current value.
HInstruction* current_value = Add<HLoadNamedField>(
heap_number, nullptr, HObjectAccess::ForHeapNumberValue());
IfBuilder value_checker(this);
value_checker.IfNot<HCompareNumericAndBranch>(current_value, value,
Token::EQ);
value_checker.ThenDeopt(DeoptimizeReason::kValueMismatch);
value_checker.End();
return nullptr;
} else {
instr = New<HStoreNamedField>(heap_number,
HObjectAccess::ForHeapNumberValue(),
value, STORE_TO_INITIALIZED_ENTRY);
}
}
} else {
if (store_to_constant_field) {
// If the field is constant check that the value we are going to store
// matches current value.
HInstruction* current_value = Add<HLoadNamedField>(
checked_object->ActualValue(), checked_object, field_access);
IfBuilder value_checker(this);
if (field_access.representation().IsDouble()) {
value_checker.IfNot<HCompareNumericAndBranch>(current_value, value,
Token::EQ);
} else {
value_checker.IfNot<HCompareObjectEqAndBranch>(current_value, value);
}
value_checker.ThenDeopt(DeoptimizeReason::kValueMismatch);
value_checker.End();
return nullptr;
} else {
if (field_access.representation().IsHeapObject()) {
BuildCheckHeapObject(value);
}
if (!info->field_maps()->is_empty()) {
DCHECK(field_access.representation().IsHeapObject());
value = Add<HCheckMaps>(value, info->field_maps());
}
// This is a normal store.
instr = New<HStoreNamedField>(checked_object->ActualValue(), field_access,
value, info->StoreMode());
}
}
if (transition_to_field) {
Handle<Map> transition(info->transition());
DCHECK(!transition->is_deprecated());
instr->SetTransition(Add<HConstant>(transition));
}
return instr;
}
Handle<FieldType>
HOptimizedGraphBuilder::PropertyAccessInfo::GetFieldTypeFromMap(
Handle<Map> map) const {
DCHECK(IsFound());
DCHECK(number_ < map->NumberOfOwnDescriptors());
return handle(map->instance_descriptors()->GetFieldType(number_), isolate());
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::IsCompatible(
PropertyAccessInfo* info) {
if (!CanInlinePropertyAccess(map_)) return false;
// Currently only handle AstType::Number as a polymorphic case.
// TODO(verwaest): Support monomorphic handling of numbers with a HCheckNumber
// instruction.
if (IsNumberType()) return false;
// Values are only compatible for monomorphic load if they all behave the same
// regarding value wrappers.
if (IsValueWrapped() != info->IsValueWrapped()) return false;
if (!LookupDescriptor()) return false;
if (!IsFound()) {
return (!info->IsFound() || info->has_holder()) &&
map()->prototype() == info->map()->prototype();
}
// Mismatch if the other access info found the property in the prototype
// chain.
if (info->has_holder()) return false;
if (IsAccessorConstant()) {
return accessor_.is_identical_to(info->accessor_) &&
api_holder_.is_identical_to(info->api_holder_);
}
if (IsDataConstant()) {
return constant_.is_identical_to(info->constant_);
}
DCHECK(IsData());
if (!info->IsData()) return false;
Representation r = access_.representation();
if (IsLoad()) {
if (!info->access_.representation().IsCompatibleForLoad(r)) return false;
} else {
if (!info->access_.representation().IsCompatibleForStore(r)) return false;
}
if (info->access_.offset() != access_.offset()) return false;
if (info->access_.IsInobject() != access_.IsInobject()) return false;
if (IsLoad()) {
if (field_maps_.is_empty()) {
info->field_maps_.Clear();
} else if (!info->field_maps_.is_empty()) {
for (int i = 0; i < field_maps_.length(); ++i) {
info->field_maps_.AddMapIfMissing(field_maps_.at(i), info->zone());
}
info->field_maps_.Sort();
}
} else {
// We can only merge stores that agree on their field maps. The comparison
// below is safe, since we keep the field maps sorted.
if (field_maps_.length() != info->field_maps_.length()) return false;
for (int i = 0; i < field_maps_.length(); ++i) {
if (!field_maps_.at(i).is_identical_to(info->field_maps_.at(i))) {
return false;
}
}
}
info->GeneralizeRepresentation(r);
info->field_type_ = info->field_type_.Combine(field_type_);
return true;
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::LookupDescriptor() {
if (!map_->IsJSObjectMap()) return true;
LookupDescriptor(*map_, *name_);
return LoadResult(map_);
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::LoadResult(Handle<Map> map) {
if (!IsLoad() && IsProperty() && IsReadOnly()) {
return false;
}
if (IsData()) {
// Construct the object field access.
int index = GetLocalFieldIndexFromMap(map);
access_ = HObjectAccess::ForField(map, index, representation(), name_);
// Load field map for heap objects.
return LoadFieldMaps(map);
} else if (IsAccessorConstant()) {
Handle<Object> accessors = GetAccessorsFromMap(map);
if (!accessors->IsAccessorPair()) return false;
Object* raw_accessor =
IsLoad() ? Handle<AccessorPair>::cast(accessors)->getter()
: Handle<AccessorPair>::cast(accessors)->setter();
if (!raw_accessor->IsJSFunction() &&
!raw_accessor->IsFunctionTemplateInfo())
return false;
Handle<Object> accessor = handle(HeapObject::cast(raw_accessor));
CallOptimization call_optimization(accessor);
if (call_optimization.is_simple_api_call()) {
CallOptimization::HolderLookup holder_lookup;
api_holder_ =
call_optimization.LookupHolderOfExpectedType(map_, &holder_lookup);
}
accessor_ = accessor;
} else if (IsDataConstant()) {
constant_ = GetConstantFromMap(map);
}
return true;
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::LoadFieldMaps(
Handle<Map> map) {
// Clear any previously collected field maps/type.
field_maps_.Clear();
field_type_ = HType::Tagged();
// Figure out the field type from the accessor map.
Handle<FieldType> field_type = GetFieldTypeFromMap(map);
// Collect the (stable) maps from the field type.
if (field_type->IsClass()) {
DCHECK(access_.representation().IsHeapObject());
Handle<Map> field_map = field_type->AsClass();
if (field_map->is_stable()) {
field_maps_.Add(field_map, zone());
}
}
if (field_maps_.is_empty()) {
// Store is not safe if the field map was cleared.
return IsLoad() || !field_type->IsNone();
}
// Determine field HType from field type.
field_type_ = HType::FromFieldType(field_type, zone());
DCHECK(field_type_.IsHeapObject());
// Add dependency on the map that introduced the field.
top_info()->dependencies()->AssumeFieldOwner(GetFieldOwnerFromMap(map));
return true;
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::LookupInPrototypes() {
Handle<Map> map = this->map();
if (name_->IsPrivate()) {
NotFound();
return !map->has_hidden_prototype();
}
while (map->prototype()->IsJSObject()) {
holder_ = handle(JSObject::cast(map->prototype()));
if (holder_->map()->is_deprecated()) {
JSObject::TryMigrateInstance(holder_);
}
map = Handle<Map>(holder_->map());
if (!CanInlinePropertyAccess(map)) {
NotFound();
return false;
}
LookupDescriptor(*map, *name_);
if (IsFound()) return LoadResult(map);
}
NotFound();
return !map->prototype()->IsJSReceiver();
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::IsIntegerIndexedExotic() {
InstanceType instance_type = map_->instance_type();
return instance_type == JS_TYPED_ARRAY_TYPE && name_->IsString() &&
IsSpecialIndex(isolate()->unicode_cache(), String::cast(*name_));
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::CanAccessMonomorphic() {
if (!CanInlinePropertyAccess(map_)) return false;
if (IsJSObjectFieldAccessor()) return IsLoad();
if (map_->IsJSFunctionMap() && map_->is_constructor() &&
!map_->has_non_instance_prototype() &&
name_.is_identical_to(isolate()->factory()->prototype_string())) {
return IsLoad();
}
if (!LookupDescriptor()) return false;
if (IsFound()) return IsLoad() || !IsReadOnly();
if (IsIntegerIndexedExotic()) return false;
if (!LookupInPrototypes()) return false;
if (IsLoad()) return true;
if (IsAccessorConstant()) return true;
LookupTransition(*map_, *name_, NONE);
if (IsTransitionToData() && map_->unused_property_fields() > 0) {
// Construct the object field access.
int descriptor = transition()->LastAdded();
int index =
transition()->instance_descriptors()->GetFieldIndex(descriptor) -
map_->GetInObjectProperties();
PropertyDetails details =
transition()->instance_descriptors()->GetDetails(descriptor);
Representation representation = details.representation();
access_ = HObjectAccess::ForField(map_, index, representation, name_);
// Load field map for heap objects.
return LoadFieldMaps(transition());
}
return false;
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::CanAccessAsMonomorphic(
SmallMapList* maps) {
DCHECK(map_.is_identical_to(maps->first()));
if (!CanAccessMonomorphic()) return false;
STATIC_ASSERT(kMaxLoadPolymorphism == kMaxStorePolymorphism);
if (maps->length() > kMaxLoadPolymorphism) return false;
HObjectAccess access = HObjectAccess::ForMap(); // bogus default
if (GetJSObjectFieldAccess(&access)) {
for (int i = 1; i < maps->length(); ++i) {
PropertyAccessInfo test_info(builder_, access_type_, maps->at(i), name_);
HObjectAccess test_access = HObjectAccess::ForMap(); // bogus default
if (!test_info.GetJSObjectFieldAccess(&test_access)) return false;
if (!access.Equals(test_access)) return false;
}
return true;
}
// Currently only handle numbers as a polymorphic case.
// TODO(verwaest): Support monomorphic handling of numbers with a HCheckNumber
// instruction.
if (IsNumberType()) return false;
// Multiple maps cannot transition to the same target map.
DCHECK(!IsLoad() || !IsTransition());
if (IsTransition() && maps->length() > 1) return false;
for (int i = 1; i < maps->length(); ++i) {
PropertyAccessInfo test_info(builder_, access_type_, maps->at(i), name_);
if (!test_info.IsCompatible(this)) return false;
}
return true;
}
Handle<Map> HOptimizedGraphBuilder::PropertyAccessInfo::map() {
Handle<JSFunction> ctor;
if (Map::GetConstructorFunction(
map_, handle(current_info()->closure()->context()->native_context()))
.ToHandle(&ctor)) {
return handle(ctor->initial_map());
}
return map_;
}
static bool NeedsWrapping(Handle<Map> map, Handle<JSFunction> target) {
return !map->IsJSObjectMap() &&
is_sloppy(target->shared()->language_mode()) &&
!target->shared()->native();
}
bool HOptimizedGraphBuilder::PropertyAccessInfo::NeedsWrappingFor(
Handle<JSFunction> target) const {
return NeedsWrapping(map_, target);
}
HValue* HOptimizedGraphBuilder::BuildMonomorphicAccess(
PropertyAccessInfo* info, HValue* object, HValue* checked_object,
HValue* value, BailoutId ast_id, BailoutId return_id,
bool can_inline_accessor) {
HObjectAccess access = HObjectAccess::ForMap(); // bogus default
if (info->GetJSObjectFieldAccess(&access)) {
DCHECK(info->IsLoad());
return New<HLoadNamedField>(object, checked_object, access);
}
if (info->name().is_identical_to(isolate()->factory()->prototype_string()) &&
info->map()->IsJSFunctionMap() && info->map()->is_constructor()) {
DCHECK(!info->map()->has_non_instance_prototype());
return New<HLoadFunctionPrototype>(checked_object);
}
HValue* checked_holder = checked_object;
if (info->has_holder()) {
Handle<JSObject> prototype(JSObject::cast(info->map()->prototype()));
checked_holder = BuildCheckPrototypeMaps(prototype, info->holder());
}
if (!info->IsFound()) {
DCHECK(info->IsLoad());
return graph()->GetConstantUndefined();
}
if (info->IsData()) {
if (info->IsLoad()) {
return BuildLoadNamedField(info, checked_holder);
} else {
return BuildStoreNamedField(info, checked_object, value);
}
}
if (info->IsTransition()) {
DCHECK(!info->IsLoad());
return BuildStoreNamedField(info, checked_object, value);
}
if (info->IsAccessorConstant()) {
MaybeHandle<Name> maybe_name =
FunctionTemplateInfo::TryGetCachedPropertyName(isolate(),
info->accessor());
if (!maybe_name.is_null()) {
Handle<Name> name = maybe_name.ToHandleChecked();
PropertyAccessInfo cache_info(this, LOAD, info->map(), name);
// Load new target.
if (cache_info.CanAccessMonomorphic()) {
return BuildLoadNamedField(&cache_info, checked_object);
}
}
Push(checked_object);
int argument_count = 1;
if (!info->IsLoad()) {
argument_count = 2;
Push(value);
}
if (info->accessor()->IsJSFunction() &&
info->NeedsWrappingFor(Handle<JSFunction>::cast(info->accessor()))) {
HValue* function = Add<HConstant>(info->accessor());
PushArgumentsFromEnvironment(argument_count);
return NewCallFunction(function, argument_count, TailCallMode::kDisallow,
ConvertReceiverMode::kNotNullOrUndefined,
TailCallMode::kDisallow);
} else if (FLAG_inline_accessors && can_inline_accessor) {
bool success = info->IsLoad()
? TryInlineGetter(info->accessor(), info->map(), ast_id, return_id)
: TryInlineSetter(
info->accessor(), info->map(), ast_id, return_id, value);
if (success || HasStackOverflow()) return NULL;
}
PushArgumentsFromEnvironment(argument_count);
if (!info->accessor()->IsJSFunction()) {
Bailout(kInliningBailedOut);
return nullptr;
}
return NewCallConstantFunction(Handle<JSFunction>::cast(info->accessor()),
argument_count, TailCallMode::kDisallow,
TailCallMode::kDisallow);
}
DCHECK(info->IsDataConstant());
if (info->IsLoad()) {
return New<HConstant>(info->constant());
} else {
return New<HCheckValue>(value, Handle<JSFunction>::cast(info->constant()));
}
}
void HOptimizedGraphBuilder::HandlePolymorphicNamedFieldAccess(
PropertyAccessType access_type, Expression* expr, FeedbackSlot slot,
BailoutId ast_id, BailoutId return_id, HValue* object, HValue* value,
SmallMapList* maps, Handle<Name> name) {
// Something did not match; must use a polymorphic load.
int count = 0;
HBasicBlock* join = NULL;
HBasicBlock* number_block = NULL;
bool handled_string = false;
bool handle_smi = false;
STATIC_ASSERT(kMaxLoadPolymorphism == kMaxStorePolymorphism);
int i;
for (i = 0; i < maps->length() && count < kMaxLoadPolymorphism; ++i) {
PropertyAccessInfo info(this, access_type, maps->at(i), name);
if (info.IsStringType()) {
if (handled_string) continue;
handled_string = true;
}
if (info.CanAccessMonomorphic()) {
count++;
if (info.IsNumberType()) {
handle_smi = true;
break;
}
}
}
if (i < maps->length()) {
count = -1;
maps->Clear();
} else {
count = 0;
}
HControlInstruction* smi_check = NULL;
handled_string = false;
for (i = 0; i < maps->length() && count < kMaxLoadPolymorphism; ++i) {
PropertyAccessInfo info(this, access_type, maps->at(i), name);
if (info.IsStringType()) {
if (handled_string) continue;
handled_string = true;
}
if (!info.CanAccessMonomorphic()) continue;
if (count == 0) {
join = graph()->CreateBasicBlock();
if (handle_smi) {
HBasicBlock* empty_smi_block = graph()->CreateBasicBlock();
HBasicBlock* not_smi_block = graph()->CreateBasicBlock();
number_block = graph()->CreateBasicBlock();
smi_check = New<HIsSmiAndBranch>(
object, empty_smi_block, not_smi_block);
FinishCurrentBlock(smi_check);
GotoNoSimulate(empty_smi_block, number_block);
set_current_block(not_smi_block);
} else {
BuildCheckHeapObject(object);
}
}
++count;
HBasicBlock* if_true = graph()->CreateBasicBlock();
HBasicBlock* if_false = graph()->CreateBasicBlock();
HUnaryControlInstruction* compare;
HValue* dependency;
if (info.IsNumberType()) {
Handle<Map> heap_number_map = isolate()->factory()->heap_number_map();
compare = New<HCompareMap>(object, heap_number_map, if_true, if_false);
dependency = smi_check;
} else if (info.IsStringType()) {
compare = New<HIsStringAndBranch>(object, if_true, if_false);
dependency = compare;
} else {
compare = New<HCompareMap>(object, info.map(), if_true, if_false);
dependency = compare;
}
FinishCurrentBlock(compare);
if (info.IsNumberType()) {
GotoNoSimulate(if_true, number_block);
if_true = number_block;
}
set_current_block(if_true);
HValue* access =
BuildMonomorphicAccess(&info, object, dependency, value, ast_id,
return_id, FLAG_polymorphic_inlining);
HValue* result = NULL;
switch (access_type) {
case LOAD:
result = access;
break;
case STORE:
result = value;
break;
}
if (access == NULL) {
if (HasStackOverflow()) return;
} else {
if (access->IsInstruction()) {
HInstruction* instr = HInstruction::cast(access);
if (!instr->IsLinked()) AddInstruction(instr);
}
if (!ast_context()->IsEffect()) Push(result);
}
if (current_block() != NULL) Goto(join);
set_current_block(if_false);
}
// Finish up. Unconditionally deoptimize if we've handled all the maps we
// know about and do not want to handle ones we've never seen. Otherwise
// use a generic IC.
if (count == maps->length() && FLAG_deoptimize_uncommon_cases) {
FinishExitWithHardDeoptimization(
DeoptimizeReason::kUnknownMapInPolymorphicAccess);
} else {
HInstruction* instr =
BuildNamedGeneric(access_type, expr, slot, object, name, value);
AddInstruction(instr);
if (!ast_context()->IsEffect()) Push(access_type == LOAD ? instr : value);
if (join != NULL) {
Goto(join);
} else {
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) ast_context()->ReturnValue(Pop());
return;
}
}
DCHECK(join != NULL);
if (join->HasPredecessor()) {
join->SetJoinId(ast_id);
set_current_block(join);
if (!ast_context()->IsEffect()) ast_context()->ReturnValue(Pop());
} else {
set_current_block(NULL);
}
}
static bool ComputeReceiverTypes(Expression* expr, HValue* receiver,
SmallMapList** t,
HOptimizedGraphBuilder* builder) {
Zone* zone = builder->zone();
SmallMapList* maps = expr->GetReceiverTypes();
*t = maps;
bool monomorphic = expr->IsMonomorphic();
if (maps != nullptr && receiver->HasMonomorphicJSObjectType()) {
if (maps->length() > 0) {
Map* root_map = receiver->GetMonomorphicJSObjectMap()->FindRootMap();
maps->FilterForPossibleTransitions(root_map);
monomorphic = maps->length() == 1;
} else {
// No type feedback, see if we can infer the type. This is safely
// possible if the receiver had a known map at some point, and no
// map-changing stores have happened to it since.
Handle<Map> candidate_map = receiver->GetMonomorphicJSObjectMap();
for (HInstruction* current = builder->current_block()->last();
current != nullptr; current = current->previous()) {
if (current->IsBlockEntry()) break;
if (current->CheckChangesFlag(kMaps)) {
// Only allow map changes that store the candidate map. We don't
// need to care which object the map is being written into.
if (!current->IsStoreNamedField()) break;
HStoreNamedField* map_change = HStoreNamedField::cast(current);
if (!map_change->value()->IsConstant()) break;
HConstant* map_constant = HConstant::cast(map_change->value());
if (!map_constant->representation().IsTagged()) break;
Handle<Object> map = map_constant->handle(builder->isolate());
if (!map.is_identical_to(candidate_map)) break;
}
if (current == receiver) {
// We made it all the way back to the receiver without encountering
// a map change! So we can assume that the receiver still has the
// candidate_map we know about.
maps->Add(candidate_map, zone);
monomorphic = true;
break;
}
}
}
}
return monomorphic && CanInlinePropertyAccess(maps->first());
}
static bool AreStringTypes(SmallMapList* maps) {
for (int i = 0; i < maps->length(); i++) {
if (maps->at(i)->instance_type() >= FIRST_NONSTRING_TYPE) return false;
}
return true;
}
void HOptimizedGraphBuilder::BuildStore(Expression* expr, Property* prop,
FeedbackSlot slot, BailoutId ast_id,
BailoutId return_id,
bool is_uninitialized) {
if (!prop->key()->IsPropertyName()) {
// Keyed store.
HValue* value = Pop();
HValue* key = Pop();
HValue* object = Pop();
bool has_side_effects = false;
HValue* result =
HandleKeyedElementAccess(object, key, value, expr, slot, ast_id,
return_id, STORE, &has_side_effects);
if (has_side_effects) {
if (!ast_context()->IsEffect()) Push(value);
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) Drop(1);
}
if (result == NULL) return;
return ast_context()->ReturnValue(value);
}
// Named store.
HValue* value = Pop();
HValue* object = Pop();
Literal* key = prop->key()->AsLiteral();
Handle<String> name = Handle<String>::cast(key->value());
DCHECK(!name.is_null());
HValue* access = BuildNamedAccess(STORE, ast_id, return_id, expr, slot,
object, name, value, is_uninitialized);
if (access == NULL) return;
if (!ast_context()->IsEffect()) Push(value);
if (access->IsInstruction()) AddInstruction(HInstruction::cast(access));
if (access->HasObservableSideEffects()) {
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
}
if (!ast_context()->IsEffect()) Drop(1);
return ast_context()->ReturnValue(value);
}
void HOptimizedGraphBuilder::HandlePropertyAssignment(Assignment* expr) {
Property* prop = expr->target()->AsProperty();
DCHECK(prop != NULL);
CHECK_ALIVE(VisitForValue(prop->obj()));
if (!prop->key()->IsPropertyName()) {
CHECK_ALIVE(VisitForValue(prop->key()));
}
CHECK_ALIVE(VisitForValue(expr->value()));
BuildStore(expr, prop, expr->AssignmentSlot(), expr->id(),
expr->AssignmentId(), expr->IsUninitialized());
}
HInstruction* HOptimizedGraphBuilder::InlineGlobalPropertyStore(
LookupIterator* it, HValue* value, BailoutId ast_id) {
Handle<PropertyCell> cell = it->GetPropertyCell();
top_info()->dependencies()->AssumePropertyCell(cell);
auto cell_type = it->property_details().cell_type();
if (cell_type == PropertyCellType::kConstant ||
cell_type == PropertyCellType::kUndefined) {
Handle<Object> constant(cell->value(), isolate());
if (value->IsConstant()) {
HConstant* c_value = HConstant::cast(value);
if (!constant.is_identical_to(c_value->handle(isolate()))) {
Add<HDeoptimize>(DeoptimizeReason::kConstantGlobalVariableAssignment,
Deoptimizer::EAGER);
}
} else {
HValue* c_constant = Add<HConstant>(constant);
IfBuilder builder(this);
if (constant->IsNumber()) {
builder.If<HCompareNumericAndBranch>(value, c_constant, Token::EQ);
} else {
builder.If<HCompareObjectEqAndBranch>(value, c_constant);
}
builder.Then();
builder.Else();
Add<HDeoptimize>(DeoptimizeReason::kConstantGlobalVariableAssignment,
Deoptimizer::EAGER);
builder.End();
}
}
HConstant* cell_constant = Add<HConstant>(cell);
auto access = HObjectAccess::ForPropertyCellValue();
if (cell_type == PropertyCellType::kConstantType) {
switch (cell->GetConstantType()) {
case PropertyCellConstantType::kSmi:
access = access.WithRepresentation(Representation::Smi());
break;
case PropertyCellConstantType::kStableMap: {
// First check that the previous value of the {cell} still has the
// map that we are about to check the new {value} for. If not, then
// the stable map assumption was invalidated and we cannot continue
// with the optimized code.
Handle<HeapObject> cell_value(HeapObject::cast(cell->value()));
Handle<Map> cell_value_map(cell_value->map());
if (!cell_value_map->is_stable()) {
Bailout(kUnstableConstantTypeHeapObject);
return nullptr;
}
top_info()->dependencies()->AssumeMapStable(cell_value_map);
// Now check that the new {value} is a HeapObject with the same map
Add<HCheckHeapObject>(value);
value = Add<HCheckMaps>(value, cell_value_map);
access = access.WithRepresentation(Representation::HeapObject());
break;
}
}
}
HInstruction* instr = New<HStoreNamedField>(cell_constant, access, value);
instr->ClearChangesFlag(kInobjectFields);
instr->SetChangesFlag(kGlobalVars);
return instr;
}
// Because not every expression has a position and there is not common
// superclass of Assignment and CountOperation, we cannot just pass the
// owning expression instead of position and ast_id separately.
void HOptimizedGraphBuilder::HandleGlobalVariableAssignment(Variable* var,
HValue* value,
FeedbackSlot slot,
BailoutId ast_id) {
Handle<JSGlobalObject> global(current_info()->global_object());
// Lookup in script contexts.
{
Handle<ScriptContextTable> script_contexts(
global->native_context()->script_context_table());
ScriptContextTable::LookupResult lookup;
if (ScriptContextTable::Lookup(script_contexts, var->name(), &lookup)) {
if (lookup.mode == CONST) {
return Bailout(kNonInitializerAssignmentToConst);
}
Handle<Context> script_context =
ScriptContextTable::GetContext(script_contexts, lookup.context_index);
Handle<Object> current_value =
FixedArray::get(*script_context, lookup.slot_index, isolate());
// If the values is not the hole, it will stay initialized,
// so no need to generate a check.
if (current_value->IsTheHole(isolate())) {
return Bailout(kReferenceToUninitializedVariable);
}
HStoreNamedField* instr = Add<HStoreNamedField>(
Add<HConstant>(script_context),
HObjectAccess::ForContextSlot(lookup.slot_index), value);
USE(instr);
DCHECK(instr->HasObservableSideEffects());
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
return;
}
}
LookupIterator it(global, var->name(), LookupIterator::OWN);
if (CanInlineGlobalPropertyAccess(var, &it, STORE)) {
HInstruction* instr = InlineGlobalPropertyStore(&it, value, ast_id);
if (!instr) return;
AddInstruction(instr);
if (instr->HasObservableSideEffects()) {
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
}
} else {
HValue* global_object = Add<HLoadNamedField>(
BuildGetNativeContext(), nullptr,
HObjectAccess::ForContextSlot(Context::EXTENSION_INDEX));
Handle<FeedbackVector> vector =
handle(current_feedback_vector(), isolate());
HValue* name = Add<HConstant>(var->name());
HValue* vector_value = Add<HConstant>(vector);
HValue* slot_value = Add<HConstant>(vector->GetIndex(slot));
DCHECK(vector->IsStoreGlobalIC(slot));
DCHECK_EQ(vector->GetLanguageMode(slot), function_language_mode());
Callable callable = CodeFactory::StoreGlobalICInOptimizedCode(
isolate(), function_language_mode());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {global_object, name, value, slot_value, vector_value};
HCallWithDescriptor* instr =
Add<HCallWithDescriptor>(Code::STORE_GLOBAL_IC, stub, 0,
callable.descriptor(), ArrayVector(values));
USE(instr);
DCHECK(instr->HasObservableSideEffects());
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
}
}
void HOptimizedGraphBuilder::HandleCompoundAssignment(Assignment* expr) {
Expression* target = expr->target();
VariableProxy* proxy = target->AsVariableProxy();
Property* prop = target->AsProperty();
DCHECK(proxy == NULL || prop == NULL);
// We have a second position recorded in the FullCodeGenerator to have
// type feedback for the binary operation.
BinaryOperation* operation = expr->binary_operation();
if (proxy != NULL) {
Variable* var = proxy->var();
if (var->mode() == LET) {
return Bailout(kUnsupportedLetCompoundAssignment);
}
CHECK_ALIVE(VisitForValue(operation));
switch (var->location()) {
case VariableLocation::UNALLOCATED:
HandleGlobalVariableAssignment(var, Top(), expr->AssignmentSlot(),
expr->AssignmentId());
break;
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL:
if (var->mode() == CONST) {
return Bailout(kNonInitializerAssignmentToConst);
}
BindIfLive(var, Top());
break;
case VariableLocation::CONTEXT: {
// Bail out if we try to mutate a parameter value in a function
// using the arguments object. We do not (yet) correctly handle the
// arguments property of the function.
if (current_info()->scope()->arguments() != NULL) {
// Parameters will be allocated to context slots. We have no
// direct way to detect that the variable is a parameter so we do
// a linear search of the parameter variables.
int count = current_info()->scope()->num_parameters();
for (int i = 0; i < count; ++i) {
if (var == current_info()->scope()->parameter(i)) {
Bailout(kAssignmentToParameterFunctionUsesArgumentsObject);
}
}
}
HStoreContextSlot::Mode mode;
switch (var->mode()) {
case LET:
mode = HStoreContextSlot::kCheckDeoptimize;
break;
case CONST:
if (var->throw_on_const_assignment(function_language_mode())) {
return Bailout(kNonInitializerAssignmentToConst);
} else {
return ast_context()->ReturnValue(Pop());
}
default:
mode = HStoreContextSlot::kNoCheck;
}
HValue* context = BuildContextChainWalk(var);
HStoreContextSlot* instr = Add<HStoreContextSlot>(
context, var->index(), mode, Top());
if (instr->HasObservableSideEffects()) {
Add<HSimulate>(expr->AssignmentId(), REMOVABLE_SIMULATE);
}
break;
}
case VariableLocation::LOOKUP:
return Bailout(kCompoundAssignmentToLookupSlot);
case VariableLocation::MODULE:
UNREACHABLE();
}
return ast_context()->ReturnValue(Pop());
} else if (prop != NULL) {
CHECK_ALIVE(VisitForValue(prop->obj()));
HValue* object = Top();
HValue* key = NULL;
if (!prop->key()->IsPropertyName() || prop->IsStringAccess()) {
CHECK_ALIVE(VisitForValue(prop->key()));
key = Top();
}
CHECK_ALIVE(PushLoad(prop, object, key));
CHECK_ALIVE(VisitForValue(expr->value()));
HValue* right = Pop();
HValue* left = Pop();
Push(BuildBinaryOperation(operation, left, right, PUSH_BEFORE_SIMULATE));
BuildStore(expr, prop, expr->AssignmentSlot(), expr->id(),
expr->AssignmentId(), expr->IsUninitialized());
} else {
return Bailout(kInvalidLhsInCompoundAssignment);
}
}
void HOptimizedGraphBuilder::VisitAssignment(Assignment* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
VariableProxy* proxy = expr->target()->AsVariableProxy();
Property* prop = expr->target()->AsProperty();
DCHECK(proxy == NULL || prop == NULL);
if (expr->is_compound()) {
HandleCompoundAssignment(expr);
return;
}
if (prop != NULL) {
HandlePropertyAssignment(expr);
} else if (proxy != NULL) {
Variable* var = proxy->var();
if (var->mode() == CONST) {
if (expr->op() != Token::INIT) {
if (var->throw_on_const_assignment(function_language_mode())) {
return Bailout(kNonInitializerAssignmentToConst);
} else {
CHECK_ALIVE(VisitForValue(expr->value()));
return ast_context()->ReturnValue(Pop());
}
}
}
// Handle the assignment.
switch (var->location()) {
case VariableLocation::UNALLOCATED:
CHECK_ALIVE(VisitForValue(expr->value()));
HandleGlobalVariableAssignment(var, Top(), expr->AssignmentSlot(),
expr->AssignmentId());
return ast_context()->ReturnValue(Pop());
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL: {
// Perform an initialization check for let declared variables
// or parameters.
if (var->mode() == LET && expr->op() == Token::ASSIGN) {
HValue* env_value = environment()->Lookup(var);
if (env_value == graph()->GetConstantHole()) {
return Bailout(kAssignmentToLetVariableBeforeInitialization);
}
}
// We do not allow the arguments object to occur in a context where it
// may escape, but assignments to stack-allocated locals are
// permitted.
CHECK_ALIVE(VisitForValue(expr->value(), ARGUMENTS_ALLOWED));
HValue* value = Pop();
BindIfLive(var, value);
return ast_context()->ReturnValue(value);
}
case VariableLocation::CONTEXT: {
// Bail out if we try to mutate a parameter value in a function using
// the arguments object. We do not (yet) correctly handle the
// arguments property of the function.
if (current_info()->scope()->arguments() != NULL) {
// Parameters will rewrite to context slots. We have no direct way
// to detect that the variable is a parameter.
int count = current_info()->scope()->num_parameters();
for (int i = 0; i < count; ++i) {
if (var == current_info()->scope()->parameter(i)) {
return Bailout(kAssignmentToParameterInArgumentsObject);
}
}
}
CHECK_ALIVE(VisitForValue(expr->value()));
HStoreContextSlot::Mode mode;
if (expr->op() == Token::ASSIGN) {
switch (var->mode()) {
case LET:
mode = HStoreContextSlot::kCheckDeoptimize;
break;
case CONST:
// If we reached this point, the only possibility
// is a sloppy assignment to a function name.
DCHECK(function_language_mode() == SLOPPY &&
!var->throw_on_const_assignment(SLOPPY));
return ast_context()->ReturnValue(Pop());
default:
mode = HStoreContextSlot::kNoCheck;
}
} else {
DCHECK_EQ(Token::INIT, expr->op());
mode = HStoreContextSlot::kNoCheck;
}
HValue* context = BuildContextChainWalk(var);
HStoreContextSlot* instr = Add<HStoreContextSlot>(
context, var->index(), mode, Top());
if (instr->HasObservableSideEffects()) {
Add<HSimulate>(expr->AssignmentId(), REMOVABLE_SIMULATE);
}
return ast_context()->ReturnValue(Pop());
}
case VariableLocation::LOOKUP:
return Bailout(kAssignmentToLOOKUPVariable);
case VariableLocation::MODULE:
UNREACHABLE();
}
} else {
return Bailout(kInvalidLeftHandSideInAssignment);
}
}
void HOptimizedGraphBuilder::VisitSuspend(Suspend* expr) {
// Generators are not optimized, so we should never get here.
UNREACHABLE();
}
void HOptimizedGraphBuilder::VisitThrow(Throw* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!ast_context()->IsEffect()) {
// The parser turns invalid left-hand sides in assignments into throw
// statements, which may not be in effect contexts. We might still try
// to optimize such functions; bail out now if we do.
return Bailout(kInvalidLeftHandSideInAssignment);
}
CHECK_ALIVE(VisitForValue(expr->exception()));
HValue* value = environment()->Pop();
if (!is_tracking_positions()) SetSourcePosition(expr->position());
Add<HPushArguments>(value);
Add<HCallRuntime>(Runtime::FunctionForId(Runtime::kThrow), 1);
Add<HSimulate>(expr->id());
// If the throw definitely exits the function, we can finish with a dummy
// control flow at this point. This is not the case if the throw is inside
// an inlined function which may be replaced.
if (call_context() == NULL) {
FinishExitCurrentBlock(New<HAbnormalExit>());
}
}
HInstruction* HGraphBuilder::AddLoadStringInstanceType(HValue* string) {
if (string->IsConstant()) {
HConstant* c_string = HConstant::cast(string);
if (c_string->HasStringValue()) {
return Add<HConstant>(c_string->StringValue()->map()->instance_type());
}
}
return Add<HLoadNamedField>(
Add<HLoadNamedField>(string, nullptr, HObjectAccess::ForMap()), nullptr,
HObjectAccess::ForMapInstanceType());
}
HInstruction* HGraphBuilder::AddLoadStringLength(HValue* string) {
return AddInstruction(BuildLoadStringLength(string));
}
HInstruction* HGraphBuilder::BuildLoadStringLength(HValue* string) {
if (string->IsConstant()) {
HConstant* c_string = HConstant::cast(string);
if (c_string->HasStringValue()) {
return New<HConstant>(c_string->StringValue()->length());
}
}
return New<HLoadNamedField>(string, nullptr,
HObjectAccess::ForStringLength());
}
HInstruction* HOptimizedGraphBuilder::BuildNamedGeneric(
PropertyAccessType access_type, Expression* expr, FeedbackSlot slot,
HValue* object, Handle<Name> name, HValue* value, bool is_uninitialized) {
if (is_uninitialized) {
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForGenericNamedAccess,
Deoptimizer::SOFT);
}
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
HValue* key = Add<HConstant>(name);
HValue* vector_value = Add<HConstant>(vector);
HValue* slot_value = Add<HConstant>(vector->GetIndex(slot));
if (access_type == LOAD) {
HValue* values[] = {object, key, slot_value, vector_value};
if (!expr->AsProperty()->key()->IsPropertyName()) {
DCHECK(vector->IsKeyedLoadIC(slot));
// It's possible that a keyed load of a constant string was converted
// to a named load. Here, at the last minute, we need to make sure to
// use a generic Keyed Load if we are using the type vector, because
// it has to share information with full code.
Callable callable = CodeFactory::KeyedLoadICInOptimizedCode(isolate());
HValue* stub = Add<HConstant>(callable.code());
HCallWithDescriptor* result =
New<HCallWithDescriptor>(Code::KEYED_LOAD_IC, stub, 0,
callable.descriptor(), ArrayVector(values));
return result;
}
DCHECK(vector->IsLoadIC(slot));
Callable callable = CodeFactory::LoadICInOptimizedCode(isolate());
HValue* stub = Add<HConstant>(callable.code());
HCallWithDescriptor* result = New<HCallWithDescriptor>(
Code::LOAD_IC, stub, 0, callable.descriptor(), ArrayVector(values));
return result;
} else {
HValue* values[] = {object, key, value, slot_value, vector_value};
if (vector->IsKeyedStoreIC(slot)) {
// It's possible that a keyed store of a constant string was converted
// to a named store. Here, at the last minute, we need to make sure to
// use a generic Keyed Store if we are using the type vector, because
// it has to share information with full code.
DCHECK_EQ(vector->GetLanguageMode(slot), function_language_mode());
Callable callable = CodeFactory::KeyedStoreICInOptimizedCode(
isolate(), function_language_mode());
HValue* stub = Add<HConstant>(callable.code());
HCallWithDescriptor* result =
New<HCallWithDescriptor>(Code::KEYED_STORE_IC, stub, 0,
callable.descriptor(), ArrayVector(values));
return result;
}
HCallWithDescriptor* result;
if (vector->IsStoreOwnIC(slot)) {
Callable callable = CodeFactory::StoreOwnICInOptimizedCode(isolate());
HValue* stub = Add<HConstant>(callable.code());
result = New<HCallWithDescriptor>(
Code::STORE_IC, stub, 0, callable.descriptor(), ArrayVector(values));
} else {
DCHECK(vector->IsStoreIC(slot));
DCHECK_EQ(vector->GetLanguageMode(slot), function_language_mode());
Callable callable = CodeFactory::StoreICInOptimizedCode(
isolate(), function_language_mode());
HValue* stub = Add<HConstant>(callable.code());
result = New<HCallWithDescriptor>(
Code::STORE_IC, stub, 0, callable.descriptor(), ArrayVector(values));
}
return result;
}
}
HInstruction* HOptimizedGraphBuilder::BuildKeyedGeneric(
PropertyAccessType access_type, Expression* expr, FeedbackSlot slot,
HValue* object, HValue* key, HValue* value) {
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
HValue* vector_value = Add<HConstant>(vector);
HValue* slot_value = Add<HConstant>(vector->GetIndex(slot));
if (access_type == LOAD) {
HValue* values[] = {object, key, slot_value, vector_value};
Callable callable = CodeFactory::KeyedLoadICInOptimizedCode(isolate());
HValue* stub = Add<HConstant>(callable.code());
HCallWithDescriptor* result =
New<HCallWithDescriptor>(Code::KEYED_LOAD_IC, stub, 0,
callable.descriptor(), ArrayVector(values));
return result;
} else {
HValue* values[] = {object, key, value, slot_value, vector_value};
Callable callable = CodeFactory::KeyedStoreICInOptimizedCode(
isolate(), function_language_mode());
HValue* stub = Add<HConstant>(callable.code());
HCallWithDescriptor* result =
New<HCallWithDescriptor>(Code::KEYED_STORE_IC, stub, 0,
callable.descriptor(), ArrayVector(values));
return result;
}
}
LoadKeyedHoleMode HOptimizedGraphBuilder::BuildKeyedHoleMode(Handle<Map> map) {
// Loads from a "stock" fast holey double arrays can elide the hole check.
// Loads from a "stock" fast holey array can convert the hole to undefined
// with impunity.
LoadKeyedHoleMode load_mode = NEVER_RETURN_HOLE;
bool holey_double_elements =
*map == isolate()->get_initial_js_array_map(FAST_HOLEY_DOUBLE_ELEMENTS);
bool holey_elements =
*map == isolate()->get_initial_js_array_map(FAST_HOLEY_ELEMENTS);
if ((holey_double_elements || holey_elements) &&
isolate()->IsFastArrayConstructorPrototypeChainIntact()) {
load_mode =
holey_double_elements ? ALLOW_RETURN_HOLE : CONVERT_HOLE_TO_UNDEFINED;
Handle<JSObject> prototype(JSObject::cast(map->prototype()), isolate());
Handle<JSObject> object_prototype = isolate()->initial_object_prototype();
BuildCheckPrototypeMaps(prototype, object_prototype);
graph()->MarkDependsOnEmptyArrayProtoElements();
}
return load_mode;
}
HInstruction* HOptimizedGraphBuilder::BuildMonomorphicElementAccess(
HValue* object,
HValue* key,
HValue* val,
HValue* dependency,
Handle<Map> map,
PropertyAccessType access_type,
KeyedAccessStoreMode store_mode) {
HCheckMaps* checked_object = Add<HCheckMaps>(object, map, dependency);
if (access_type == STORE && map->prototype()->IsJSObject()) {
// monomorphic stores need a prototype chain check because shape
// changes could allow callbacks on elements in the chain that
// aren't compatible with monomorphic keyed stores.
PrototypeIterator iter(map);
JSObject* holder = NULL;
while (!iter.IsAtEnd()) {
// JSProxies can't occur here because we wouldn't have installed a
// non-generic IC if there were any.
holder = *PrototypeIterator::GetCurrent<JSObject>(iter);
iter.Advance();
}
DCHECK(holder && holder->IsJSObject());
BuildCheckPrototypeMaps(handle(JSObject::cast(map->prototype())),
Handle<JSObject>(holder));
}
LoadKeyedHoleMode load_mode = BuildKeyedHoleMode(map);
return BuildUncheckedMonomorphicElementAccess(
checked_object, key, val,
map->instance_type() == JS_ARRAY_TYPE,
map->elements_kind(), access_type,
load_mode, store_mode);
}
static bool CanInlineElementAccess(Handle<Map> map) {
return map->IsJSObjectMap() &&
(map->has_fast_elements() || map->has_fixed_typed_array_elements()) &&
!map->has_indexed_interceptor() && !map->is_access_check_needed();
}
HInstruction* HOptimizedGraphBuilder::TryBuildConsolidatedElementLoad(
HValue* object,
HValue* key,
HValue* val,
SmallMapList* maps) {
// For polymorphic loads of similar elements kinds (i.e. all tagged or all
// double), always use the "worst case" code without a transition. This is
// much faster than transitioning the elements to the worst case, trading a
// HTransitionElements for a HCheckMaps, and avoiding mutation of the array.
bool has_double_maps = false;
bool has_smi_or_object_maps = false;
bool has_js_array_access = false;
bool has_non_js_array_access = false;
bool has_seen_holey_elements = false;
Handle<Map> most_general_consolidated_map;
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
if (!CanInlineElementAccess(map)) return NULL;
// Don't allow mixing of JSArrays with JSObjects.
if (map->instance_type() == JS_ARRAY_TYPE) {
if (has_non_js_array_access) return NULL;
has_js_array_access = true;
} else if (has_js_array_access) {
return NULL;
} else {
has_non_js_array_access = true;
}
// Don't allow mixed, incompatible elements kinds.
if (map->has_fast_double_elements()) {
if (has_smi_or_object_maps) return NULL;
has_double_maps = true;
} else if (map->has_fast_smi_or_object_elements()) {
if (has_double_maps) return NULL;
has_smi_or_object_maps = true;
} else {
return NULL;
}
// Remember if we've ever seen holey elements.
if (IsHoleyElementsKind(map->elements_kind())) {
has_seen_holey_elements = true;
}
// Remember the most general elements kind, the code for its load will
// properly handle all of the more specific cases.
if ((i == 0) || IsMoreGeneralElementsKindTransition(
most_general_consolidated_map->elements_kind(),
map->elements_kind())) {
most_general_consolidated_map = map;
}
}
if (!has_double_maps && !has_smi_or_object_maps) return NULL;
HCheckMaps* checked_object = Add<HCheckMaps>(object, maps);
// FAST_ELEMENTS is considered more general than FAST_HOLEY_SMI_ELEMENTS.
// If we've seen both, the consolidated load must use FAST_HOLEY_ELEMENTS.
ElementsKind consolidated_elements_kind = has_seen_holey_elements
? GetHoleyElementsKind(most_general_consolidated_map->elements_kind())
: most_general_consolidated_map->elements_kind();
LoadKeyedHoleMode load_mode = NEVER_RETURN_HOLE;
if (has_seen_holey_elements) {
// Make sure that all of the maps we are handling have the initial array
// prototype.
bool saw_non_array_prototype = false;
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
if (map->prototype() != *isolate()->initial_array_prototype()) {
// We can't guarantee that loading the hole is safe. The prototype may
// have an element at this position.
saw_non_array_prototype = true;
break;
}
}
if (!saw_non_array_prototype) {
Handle<Map> holey_map = handle(
isolate()->get_initial_js_array_map(consolidated_elements_kind));
load_mode = BuildKeyedHoleMode(holey_map);
if (load_mode != NEVER_RETURN_HOLE) {
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
// The prototype check was already done for the holey map in
// BuildKeyedHoleMode.
if (!map.is_identical_to(holey_map)) {
Handle<JSObject> prototype(JSObject::cast(map->prototype()),
isolate());
Handle<JSObject> object_prototype =
isolate()->initial_object_prototype();
BuildCheckPrototypeMaps(prototype, object_prototype);
}
}
}
}
}
HInstruction* instr = BuildUncheckedMonomorphicElementAccess(
checked_object, key, val,
most_general_consolidated_map->instance_type() == JS_ARRAY_TYPE,
consolidated_elements_kind, LOAD, load_mode, STANDARD_STORE);
return instr;
}
HValue* HOptimizedGraphBuilder::HandlePolymorphicElementAccess(
Expression* expr, FeedbackSlot slot, HValue* object, HValue* key,
HValue* val, SmallMapList* maps, PropertyAccessType access_type,
KeyedAccessStoreMode store_mode, bool* has_side_effects) {
*has_side_effects = false;
BuildCheckHeapObject(object);
if (access_type == LOAD) {
HInstruction* consolidated_load =
TryBuildConsolidatedElementLoad(object, key, val, maps);
if (consolidated_load != NULL) {
*has_side_effects |= consolidated_load->HasObservableSideEffects();
return consolidated_load;
}
}
// Elements_kind transition support.
MapHandles transition_target;
transition_target.reserve(maps->length());
// Collect possible transition targets.
MapHandles possible_transitioned_maps;
possible_transitioned_maps.reserve(maps->length());
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
// Loads from strings or loads with a mix of string and non-string maps
// shouldn't be handled polymorphically.
DCHECK(access_type != LOAD || !map->IsStringMap());
ElementsKind elements_kind = map->elements_kind();
if (CanInlineElementAccess(map) && IsFastElementsKind(elements_kind) &&
elements_kind != GetInitialFastElementsKind()) {
possible_transitioned_maps.push_back(map);
}
if (IsSloppyArgumentsElementsKind(elements_kind)) {
HInstruction* result =
BuildKeyedGeneric(access_type, expr, slot, object, key, val);
*has_side_effects = result->HasObservableSideEffects();
return AddInstruction(result);
}
}
// Get transition target for each map (NULL == no transition).
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
// Don't generate elements kind transitions from stable maps.
Map* transitioned_map =
map->is_stable()
? nullptr
: map->FindElementsKindTransitionedMap(possible_transitioned_maps);
if (transitioned_map != nullptr) {
transition_target.push_back(handle(transitioned_map));
} else {
transition_target.push_back(Handle<Map>());
}
}
MapHandles untransitionable_maps;
untransitionable_maps.reserve(maps->length());
HTransitionElementsKind* transition = NULL;
for (int i = 0; i < maps->length(); ++i) {
Handle<Map> map = maps->at(i);
DCHECK(map->IsMap());
if (!transition_target.at(i).is_null()) {
DCHECK(Map::IsValidElementsTransition(
map->elements_kind(),
transition_target.at(i)->elements_kind()));
transition = Add<HTransitionElementsKind>(object, map,
transition_target.at(i));
} else {
untransitionable_maps.push_back(map);
}
}
// If only one map is left after transitioning, handle this case
// monomorphically.
DCHECK(untransitionable_maps.size() >= 1);
if (untransitionable_maps.size() == 1) {
Handle<Map> untransitionable_map = untransitionable_maps[0];
HInstruction* instr = NULL;
if (!CanInlineElementAccess(untransitionable_map)) {
instr = AddInstruction(
BuildKeyedGeneric(access_type, expr, slot, object, key, val));
} else {
instr = BuildMonomorphicElementAccess(
object, key, val, transition, untransitionable_map, access_type,
store_mode);
}
*has_side_effects |= instr->HasObservableSideEffects();
return access_type == STORE ? val : instr;
}
HBasicBlock* join = graph()->CreateBasicBlock();
for (Handle<Map> map : untransitionable_maps) {
ElementsKind elements_kind = map->elements_kind();
HBasicBlock* this_map = graph()->CreateBasicBlock();
HBasicBlock* other_map = graph()->CreateBasicBlock();
HCompareMap* mapcompare =
New<HCompareMap>(object, map, this_map, other_map);
FinishCurrentBlock(mapcompare);
set_current_block(this_map);
HInstruction* access = NULL;
if (!CanInlineElementAccess(map)) {
access = AddInstruction(
BuildKeyedGeneric(access_type, expr, slot, object, key, val));
} else {
DCHECK(IsFastElementsKind(elements_kind) ||
IsFixedTypedArrayElementsKind(elements_kind));
LoadKeyedHoleMode load_mode = BuildKeyedHoleMode(map);
// Happily, mapcompare is a checked object.
access = BuildUncheckedMonomorphicElementAccess(
mapcompare, key, val,
map->instance_type() == JS_ARRAY_TYPE,
elements_kind, access_type,
load_mode,
store_mode);
}
*has_side_effects |= access->HasObservableSideEffects();
// The caller will use has_side_effects and add a correct Simulate.
access->SetFlag(HValue::kHasNoObservableSideEffects);
if (access_type == LOAD) {
Push(access);
}
NoObservableSideEffectsScope scope(this);
GotoNoSimulate(join);
set_current_block(other_map);
}
// Ensure that we visited at least one map above that goes to join. This is
// necessary because FinishExitWithHardDeoptimization does an AbnormalExit
// rather than joining the join block. If this becomes an issue, insert a
// generic access in the case length() == 0.
DCHECK(join->predecessors()->length() > 0);
// Deopt if none of the cases matched.
NoObservableSideEffectsScope scope(this);
FinishExitWithHardDeoptimization(
DeoptimizeReason::kUnknownMapInPolymorphicElementAccess);
set_current_block(join);
return access_type == STORE ? val : Pop();
}
HValue* HOptimizedGraphBuilder::HandleKeyedElementAccess(
HValue* obj, HValue* key, HValue* val, Expression* expr, FeedbackSlot slot,
BailoutId ast_id, BailoutId return_id, PropertyAccessType access_type,
bool* has_side_effects) {
// A keyed name access with type feedback may contain the name.
Handle<FeedbackVector> vector = handle(current_feedback_vector(), isolate());
HValue* expected_key = key;
if (!key->ActualValue()->IsConstant()) {
Name* name = nullptr;
if (access_type == LOAD) {
KeyedLoadICNexus nexus(vector, slot);
name = nexus.FindFirstName();
} else {
KeyedStoreICNexus nexus(vector, slot);
name = nexus.FindFirstName();
}
if (name != nullptr) {
Handle<Name> handle_name(name);
expected_key = Add<HConstant>(handle_name);
// We need a check against the key.
bool in_new_space = isolate()->heap()->InNewSpace(*handle_name);
Unique<Name> unique_name = Unique<Name>::CreateUninitialized(handle_name);
Add<HCheckValue>(key, unique_name, in_new_space);
}
}
if (expected_key->ActualValue()->IsConstant()) {
Handle<Object> constant =
HConstant::cast(expected_key->ActualValue())->handle(isolate());
uint32_t array_index;
if ((constant->IsString() &&
!Handle<String>::cast(constant)->AsArrayIndex(&array_index)) ||
constant->IsSymbol()) {
if (!constant->IsUniqueName()) {
constant = isolate()->factory()->InternalizeString(
Handle<String>::cast(constant));
}
HValue* access =
BuildNamedAccess(access_type, ast_id, return_id, expr, slot, obj,
Handle<Name>::cast(constant), val, false);
if (access == NULL || access->IsPhi() ||
HInstruction::cast(access)->IsLinked()) {
*has_side_effects = false;
} else {
HInstruction* instr = HInstruction::cast(access);
AddInstruction(instr);
*has_side_effects = instr->HasObservableSideEffects();
}
return access;
}
}
DCHECK(!expr->IsPropertyName());
HInstruction* instr = NULL;
SmallMapList* maps;
bool monomorphic = ComputeReceiverTypes(expr, obj, &maps, this);
bool force_generic = false;
if (expr->GetKeyType() == PROPERTY) {
// Non-Generic accesses assume that elements are being accessed, and will
// deopt for non-index keys, which the IC knows will occur.
// TODO(jkummerow): Consider adding proper support for property accesses.
force_generic = true;
monomorphic = false;
} else if (access_type == STORE &&
(monomorphic || (maps != NULL && !maps->is_empty()))) {
// Stores can't be mono/polymorphic if their prototype chain has dictionary
// elements. However a receiver map that has dictionary elements itself
// should be left to normal mono/poly behavior (the other maps may benefit
// from highly optimized stores).
for (int i = 0; i < maps->length(); i++) {
Handle<Map> current_map = maps->at(i);
if (current_map->DictionaryElementsInPrototypeChainOnly()) {
force_generic = true;
monomorphic = false;
break;
}
}
} else if (access_type == LOAD && !monomorphic &&
(maps != NULL && !maps->is_empty())) {
// Polymorphic loads have to go generic if any of the maps are strings.
// If some, but not all of the maps are strings, we should go generic
// because polymorphic access wants to key on ElementsKind and isn't
// compatible with strings.
for (int i = 0; i < maps->length(); i++) {
Handle<Map> current_map = maps->at(i);
if (current_map->IsStringMap()) {
force_generic = true;
break;
}
}
}
if (monomorphic) {
Handle<Map> map = maps->first();
if (!CanInlineElementAccess(map)) {
instr = AddInstruction(
BuildKeyedGeneric(access_type, expr, slot, obj, key, val));
} else {
BuildCheckHeapObject(obj);
instr = BuildMonomorphicElementAccess(
obj, key, val, NULL, map, access_type, expr->GetStoreMode());
}
} else if (!force_generic && (maps != NULL && !maps->is_empty())) {
return HandlePolymorphicElementAccess(expr, slot, obj, key, val, maps,
access_type, expr->GetStoreMode(),
has_side_effects);
} else {
if (access_type == STORE) {
if (expr->IsAssignment() &&
expr->AsAssignment()->HasNoTypeInformation()) {
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForGenericKeyedAccess,
Deoptimizer::SOFT);
}
} else {
if (expr->AsProperty()->HasNoTypeInformation()) {
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForGenericKeyedAccess,
Deoptimizer::SOFT);
}
}
instr = AddInstruction(
BuildKeyedGeneric(access_type, expr, slot, obj, key, val));
}
*has_side_effects = instr->HasObservableSideEffects();
return instr;
}
void HOptimizedGraphBuilder::EnsureArgumentsArePushedForAccess() {
// Outermost function already has arguments on the stack.
if (function_state()->outer() == NULL) return;
if (function_state()->arguments_pushed()) return;
// Push arguments when entering inlined function.
HEnterInlined* entry = function_state()->entry();
entry->set_arguments_pushed();
HArgumentsObject* arguments = entry->arguments_object();
const ZoneList<HValue*>* arguments_values = arguments->arguments_values();
HInstruction* insert_after = entry;
for (int i = 0; i < arguments_values->length(); i++) {
HValue* argument = arguments_values->at(i);
HInstruction* push_argument = New<HPushArguments>(argument);
push_argument->InsertAfter(insert_after);
insert_after = push_argument;
}
HArgumentsElements* arguments_elements = New<HArgumentsElements>(true);
arguments_elements->ClearFlag(HValue::kUseGVN);
arguments_elements->InsertAfter(insert_after);
function_state()->set_arguments_elements(arguments_elements);
}
bool HOptimizedGraphBuilder::IsAnyParameterContextAllocated() {
int count = current_info()->scope()->num_parameters();
for (int i = 0; i < count; ++i) {
if (current_info()->scope()->parameter(i)->location() ==
VariableLocation::CONTEXT) {
return true;
}
}
return false;
}
bool HOptimizedGraphBuilder::TryArgumentsAccess(Property* expr) {
VariableProxy* proxy = expr->obj()->AsVariableProxy();
if (proxy == NULL) return false;
if (!proxy->var()->IsStackAllocated()) return false;
if (!environment()->Lookup(proxy->var())->CheckFlag(HValue::kIsArguments)) {
return false;
}
HInstruction* result = NULL;
if (expr->key()->IsPropertyName()) {
Handle<String> name = expr->key()->AsLiteral()->AsPropertyName();
if (!String::Equals(name, isolate()->factory()->length_string())) {
return false;
}
// Make sure we visit the arguments object so that the liveness analysis
// still records the access.
CHECK_ALIVE_OR_RETURN(VisitForValue(expr->obj(), ARGUMENTS_ALLOWED), true);
Drop(1);
if (function_state()->outer() == NULL) {
HInstruction* elements = Add<HArgumentsElements>(false);
result = New<HArgumentsLength>(elements);
} else {
// Number of arguments without receiver.
int argument_count = environment()->
arguments_environment()->parameter_count() - 1;
result = New<HConstant>(argument_count);
}
} else {
// We need to take into account the KEYED_LOAD_IC feedback to guard the
// HBoundsCheck instructions below.
if (!expr->IsMonomorphic() && !expr->IsUninitialized()) return false;
if (IsAnyParameterContextAllocated()) return false;
CHECK_ALIVE_OR_RETURN(VisitForValue(expr->obj(), ARGUMENTS_ALLOWED), true);
CHECK_ALIVE_OR_RETURN(VisitForValue(expr->key()), true);
HValue* key = Pop();
Drop(1); // Arguments object.
if (function_state()->outer() == NULL) {
HInstruction* elements = Add<HArgumentsElements>(false);
HInstruction* length = Add<HArgumentsLength>(elements);
HInstruction* checked_key = Add<HBoundsCheck>(key, length);
result = New<HAccessArgumentsAt>(elements, length, checked_key);
} else {
EnsureArgumentsArePushedForAccess();
// Number of arguments without receiver.
HInstruction* elements = function_state()->arguments_elements();
int argument_count = environment()->
arguments_environment()->parameter_count() - 1;
HInstruction* length = Add<HConstant>(argument_count);
HInstruction* checked_key = Add<HBoundsCheck>(key, length);
result = New<HAccessArgumentsAt>(elements, length, checked_key);
}
}
ast_context()->ReturnInstruction(result, expr->id());
return true;
}
HValue* HOptimizedGraphBuilder::BuildNamedAccess(
PropertyAccessType access, BailoutId ast_id, BailoutId return_id,
Expression* expr, FeedbackSlot slot, HValue* object, Handle<Name> name,
HValue* value, bool is_uninitialized) {
SmallMapList* maps;
ComputeReceiverTypes(expr, object, &maps, this);
DCHECK(maps != NULL);
// Check for special case: Access via a single map to the global proxy
// can also be handled monomorphically.
if (maps->length() > 0) {
Handle<Object> map_constructor =
handle(maps->first()->GetConstructor(), isolate());
if (map_constructor->IsJSFunction()) {
Handle<Context> map_context =
handle(Handle<JSFunction>::cast(map_constructor)->context());
Handle<Context> current_context(current_info()->context());
bool is_same_context_global_proxy_access =
maps->length() == 1 && // >1 map => fallback to polymorphic
maps->first()->IsJSGlobalProxyMap() &&
(*map_context == *current_context);
if (is_same_context_global_proxy_access) {
Handle<JSGlobalObject> global_object(current_info()->global_object());
LookupIterator it(global_object, name, LookupIterator::OWN);
if (CanInlineGlobalPropertyAccess(&it, access)) {
BuildCheckHeapObject(object);
Add<HCheckMaps>(object, maps);
if (access == LOAD) {
InlineGlobalPropertyLoad(&it, expr->id());
return nullptr;
} else {
return InlineGlobalPropertyStore(&it, value, expr->id());
}
}
}
}
PropertyAccessInfo info(this, access, maps->first(), name);
if (!info.CanAccessAsMonomorphic(maps)) {
HandlePolymorphicNamedFieldAccess(access, expr, slot, ast_id, return_id,
object, value, maps, name);
return NULL;
}
HValue* checked_object;
// AstType::Number() is only supported by polymorphic load/call handling.
DCHECK(!info.IsNumberType());
BuildCheckHeapObject(object);
if (AreStringTypes(maps)) {
checked_object =
Add<HCheckInstanceType>(object, HCheckInstanceType::IS_STRING);
} else {
checked_object = Add<HCheckMaps>(object, maps);
}
return BuildMonomorphicAccess(
&info, object, checked_object, value, ast_id, return_id);
}
return BuildNamedGeneric(access, expr, slot, object, name, value,
is_uninitialized);
}
void HOptimizedGraphBuilder::PushLoad(Property* expr,
HValue* object,
HValue* key) {
ValueContext for_value(this, ARGUMENTS_NOT_ALLOWED);
Push(object);
if (key != NULL) Push(key);
BuildLoad(expr, expr->LoadId());
}
void HOptimizedGraphBuilder::BuildLoad(Property* expr,
BailoutId ast_id) {
HInstruction* instr = NULL;
if (expr->IsStringAccess() && expr->GetKeyType() == ELEMENT) {
HValue* index = Pop();
HValue* string = Pop();
HInstruction* char_code = BuildStringCharCodeAt(string, index);
AddInstruction(char_code);
if (char_code->IsConstant()) {
HConstant* c_code = HConstant::cast(char_code);
if (c_code->HasNumberValue() && std::isnan(c_code->DoubleValue())) {
Add<HDeoptimize>(DeoptimizeReason::kOutOfBounds, Deoptimizer::EAGER);
}
}
instr = NewUncasted<HStringCharFromCode>(char_code);
} else if (expr->key()->IsPropertyName()) {
Handle<String> name = expr->key()->AsLiteral()->AsPropertyName();
HValue* object = Pop();
HValue* value = BuildNamedAccess(LOAD, ast_id, expr->LoadId(), expr,
expr->PropertyFeedbackSlot(), object, name,
NULL, expr->IsUninitialized());
if (value == NULL) return;
if (value->IsPhi()) return ast_context()->ReturnValue(value);
instr = HInstruction::cast(value);
if (instr->IsLinked()) return ast_context()->ReturnValue(instr);
} else {
HValue* key = Pop();
HValue* obj = Pop();
bool has_side_effects = false;
HValue* load = HandleKeyedElementAccess(
obj, key, NULL, expr, expr->PropertyFeedbackSlot(), ast_id,
expr->LoadId(), LOAD, &has_side_effects);
if (has_side_effects) {
if (ast_context()->IsEffect()) {
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
} else {
Push(load);
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
Drop(1);
}
}
if (load == NULL) return;
return ast_context()->ReturnValue(load);
}
return ast_context()->ReturnInstruction(instr, ast_id);
}
void HOptimizedGraphBuilder::VisitProperty(Property* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (TryArgumentsAccess(expr)) return;
CHECK_ALIVE(VisitForValue(expr->obj()));
if (!expr->key()->IsPropertyName() || expr->IsStringAccess()) {
CHECK_ALIVE(VisitForValue(expr->key()));
}
BuildLoad(expr, expr->id());
}
HInstruction* HGraphBuilder::BuildConstantMapCheck(Handle<JSObject> constant,
bool ensure_no_elements) {
HCheckMaps* check = Add<HCheckMaps>(
Add<HConstant>(constant), handle(constant->map()));
check->ClearDependsOnFlag(kElementsKind);
if (ensure_no_elements) {
// TODO(ishell): remove this once we support NO_ELEMENTS elements kind.
HValue* elements = AddLoadElements(check, nullptr);
HValue* empty_elements =
Add<HConstant>(isolate()->factory()->empty_fixed_array());
IfBuilder if_empty(this);
if_empty.IfNot<HCompareObjectEqAndBranch>(elements, empty_elements);
if_empty.ThenDeopt(DeoptimizeReason::kWrongMap);
if_empty.End();
}
return check;
}
HInstruction* HGraphBuilder::BuildCheckPrototypeMaps(Handle<JSObject> prototype,
Handle<JSObject> holder,
bool ensure_no_elements) {
PrototypeIterator iter(isolate(), prototype, kStartAtReceiver);
while (holder.is_null() ||
!PrototypeIterator::GetCurrent(iter).is_identical_to(holder)) {
BuildConstantMapCheck(PrototypeIterator::GetCurrent<JSObject>(iter),
ensure_no_elements);
iter.Advance();
if (iter.IsAtEnd()) {
return NULL;
}
}
return BuildConstantMapCheck(holder);
}
void HOptimizedGraphBuilder::AddCheckPrototypeMaps(Handle<JSObject> holder,
Handle<Map> receiver_map) {
if (!holder.is_null()) {
Handle<JSObject> prototype(JSObject::cast(receiver_map->prototype()));
BuildCheckPrototypeMaps(prototype, holder);
}
}
void HOptimizedGraphBuilder::BuildEnsureCallable(HValue* object) {
NoObservableSideEffectsScope scope(this);
const Runtime::Function* throw_called_non_callable =
Runtime::FunctionForId(Runtime::kThrowCalledNonCallable);
IfBuilder is_not_function(this);
HValue* smi_check = is_not_function.If<HIsSmiAndBranch>(object);
is_not_function.Or();
HValue* map = AddLoadMap(object, smi_check);
HValue* bit_field =
Add<HLoadNamedField>(map, nullptr, HObjectAccess::ForMapBitField());
HValue* bit_field_masked = AddUncasted<HBitwise>(
Token::BIT_AND, bit_field, Add<HConstant>(1 << Map::kIsCallable));
is_not_function.IfNot<HCompareNumericAndBranch>(
bit_field_masked, Add<HConstant>(1 << Map::kIsCallable), Token::EQ);
is_not_function.Then();
{
Add<HPushArguments>(object);
Add<HCallRuntime>(throw_called_non_callable, 1);
}
is_not_function.End();
}
HInstruction* HOptimizedGraphBuilder::NewCallFunction(
HValue* function, int argument_count, TailCallMode syntactic_tail_call_mode,
ConvertReceiverMode convert_mode, TailCallMode tail_call_mode) {
if (syntactic_tail_call_mode == TailCallMode::kAllow) {
BuildEnsureCallable(function);
} else {
DCHECK_EQ(TailCallMode::kDisallow, tail_call_mode);
}
HValue* arity = Add<HConstant>(argument_count - 1);
HValue* op_vals[] = {function, arity};
Callable callable =
CodeFactory::Call(isolate(), convert_mode, tail_call_mode);
HConstant* stub = Add<HConstant>(callable.code());
return New<HCallWithDescriptor>(stub, argument_count, callable.descriptor(),
ArrayVector(op_vals),
syntactic_tail_call_mode);
}
HInstruction* HOptimizedGraphBuilder::NewCallFunctionViaIC(
HValue* function, int argument_count, TailCallMode syntactic_tail_call_mode,
ConvertReceiverMode convert_mode, TailCallMode tail_call_mode,
FeedbackSlot slot) {
if (syntactic_tail_call_mode == TailCallMode::kAllow) {
BuildEnsureCallable(function);
} else {
DCHECK_EQ(TailCallMode::kDisallow, tail_call_mode);
}
int arity = argument_count - 1;
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
HValue* arity_val = Add<HConstant>(arity);
HValue* index_val = Add<HConstant>(vector->GetIndex(slot));
HValue* vector_val = Add<HConstant>(vector);
HValue* op_vals[] = {function, arity_val, index_val, vector_val};
Callable callable =
CodeFactory::CallIC(isolate(), convert_mode, tail_call_mode);
HConstant* stub = Add<HConstant>(callable.code());
return New<HCallWithDescriptor>(stub, argument_count, callable.descriptor(),
ArrayVector(op_vals),
syntactic_tail_call_mode);
}
HInstruction* HOptimizedGraphBuilder::NewCallConstantFunction(
Handle<JSFunction> function, int argument_count,
TailCallMode syntactic_tail_call_mode, TailCallMode tail_call_mode) {
HValue* target = Add<HConstant>(function);
return New<HInvokeFunction>(target, function, argument_count,
syntactic_tail_call_mode, tail_call_mode);
}
class FunctionSorter {
public:
explicit FunctionSorter(int index = 0, int ticks = 0, int size = 0)
: index_(index), ticks_(ticks), size_(size) {}
int index() const { return index_; }
int ticks() const { return ticks_; }
int size() const { return size_; }
private:
int index_;
int ticks_;
int size_;
};
inline bool operator<(const FunctionSorter& lhs, const FunctionSorter& rhs) {
int diff = lhs.ticks() - rhs.ticks();
if (diff != 0) return diff > 0;
return lhs.size() < rhs.size();
}
void HOptimizedGraphBuilder::HandlePolymorphicCallNamed(Call* expr,
HValue* receiver,
SmallMapList* maps,
Handle<String> name) {
int argument_count = expr->arguments()->length() + 1; // Includes receiver.
FunctionSorter order[kMaxCallPolymorphism];
bool handle_smi = false;
bool handled_string = false;
int ordered_functions = 0;
TailCallMode syntactic_tail_call_mode = expr->tail_call_mode();
TailCallMode tail_call_mode =
function_state()->ComputeTailCallMode(syntactic_tail_call_mode);
int i;
for (i = 0; i < maps->length() && ordered_functions < kMaxCallPolymorphism;
++i) {
PropertyAccessInfo info(this, LOAD, maps->at(i), name);
if (info.CanAccessMonomorphic() && info.IsDataConstant() &&
info.constant()->IsJSFunction()) {
if (info.IsStringType()) {
if (handled_string) continue;
handled_string = true;
}
Handle<JSFunction> target = Handle<JSFunction>::cast(info.constant());
if (info.IsNumberType()) {
handle_smi = true;
}
expr->set_target(target);
order[ordered_functions++] = FunctionSorter(
i, target->shared()->profiler_ticks(), InliningAstSize(target));
}
}
std::sort(order, order + ordered_functions);
if (i < maps->length()) {
maps->Clear();
ordered_functions = -1;
}
HBasicBlock* number_block = NULL;
HBasicBlock* join = NULL;
handled_string = false;
int count = 0;
for (int fn = 0; fn < ordered_functions; ++fn) {
int i = order[fn].index();
PropertyAccessInfo info(this, LOAD, maps->at(i), name);
if (info.IsStringType()) {
if (handled_string) continue;
handled_string = true;
}
// Reloads the target.
info.CanAccessMonomorphic();
Handle<JSFunction> target = Handle<JSFunction>::cast(info.constant());
expr->set_target(target);
if (count == 0) {
// Only needed once.
join = graph()->CreateBasicBlock();
if (handle_smi) {
HBasicBlock* empty_smi_block = graph()->CreateBasicBlock();
HBasicBlock* not_smi_block = graph()->CreateBasicBlock();
number_block = graph()->CreateBasicBlock();
FinishCurrentBlock(New<HIsSmiAndBranch>(
receiver, empty_smi_block, not_smi_block));
GotoNoSimulate(empty_smi_block, number_block);
set_current_block(not_smi_block);
} else {
BuildCheckHeapObject(receiver);
}
}
++count;
HBasicBlock* if_true = graph()->CreateBasicBlock();
HBasicBlock* if_false = graph()->CreateBasicBlock();
HUnaryControlInstruction* compare;
Handle<Map> map = info.map();
if (info.IsNumberType()) {
Handle<Map> heap_number_map = isolate()->factory()->heap_number_map();
compare = New<HCompareMap>(receiver, heap_number_map, if_true, if_false);
} else if (info.IsStringType()) {
compare = New<HIsStringAndBranch>(receiver, if_true, if_false);
} else {
compare = New<HCompareMap>(receiver, map, if_true, if_false);
}
FinishCurrentBlock(compare);
if (info.IsNumberType()) {
GotoNoSimulate(if_true, number_block);
if_true = number_block;
}
set_current_block(if_true);
AddCheckPrototypeMaps(info.holder(), map);
HValue* function = Add<HConstant>(expr->target());
environment()->SetExpressionStackAt(0, function);
Push(receiver);
CHECK_ALIVE(VisitExpressions(expr->arguments()));
bool needs_wrapping = info.NeedsWrappingFor(target);
bool try_inline = FLAG_polymorphic_inlining && !needs_wrapping;
if (FLAG_trace_inlining && try_inline) {
Handle<JSFunction> caller = current_info()->closure();
std::unique_ptr<char[]> caller_name =
caller->shared()->DebugName()->ToCString();
PrintF("Trying to inline the polymorphic call to %s from %s\n",
name->ToCString().get(),
caller_name.get());
}
if (try_inline && TryInlineCall(expr)) {
// Trying to inline will signal that we should bailout from the
// entire compilation by setting stack overflow on the visitor.
if (HasStackOverflow()) return;
} else {
// Since HWrapReceiver currently cannot actually wrap numbers and strings,
// use the regular call builtin for method calls to wrap the receiver.
// TODO(verwaest): Support creation of value wrappers directly in
// HWrapReceiver.
HInstruction* call =
needs_wrapping
? NewCallFunction(
function, argument_count, syntactic_tail_call_mode,
ConvertReceiverMode::kNotNullOrUndefined, tail_call_mode)
: NewCallConstantFunction(target, argument_count,
syntactic_tail_call_mode,
tail_call_mode);
PushArgumentsFromEnvironment(argument_count);
AddInstruction(call);
Drop(1); // Drop the function.
if (!ast_context()->IsEffect()) Push(call);
}
if (current_block() != NULL) Goto(join);
set_current_block(if_false);
}
// Finish up. Unconditionally deoptimize if we've handled all the maps we
// know about and do not want to handle ones we've never seen. Otherwise
// use a generic IC.
if (ordered_functions == maps->length() && FLAG_deoptimize_uncommon_cases) {
FinishExitWithHardDeoptimization(
DeoptimizeReason::kUnknownMapInPolymorphicCall);
} else {
Property* prop = expr->expression()->AsProperty();
HInstruction* function =
BuildNamedGeneric(LOAD, prop, prop->PropertyFeedbackSlot(), receiver,
name, NULL, prop->IsUninitialized());
AddInstruction(function);
Push(function);
AddSimulate(prop->LoadId(), REMOVABLE_SIMULATE);
environment()->SetExpressionStackAt(1, function);
environment()->SetExpressionStackAt(0, receiver);
CHECK_ALIVE(VisitExpressions(expr->arguments()));
HInstruction* call = NewCallFunction(
function, argument_count, syntactic_tail_call_mode,
ConvertReceiverMode::kNotNullOrUndefined, tail_call_mode);
PushArgumentsFromEnvironment(argument_count);
Drop(1); // Function.
if (join != NULL) {
AddInstruction(call);
if (!ast_context()->IsEffect()) Push(call);
Goto(join);
} else {
return ast_context()->ReturnInstruction(call, expr->id());
}
}
// We assume that control flow is always live after an expression. So
// even without predecessors to the join block, we set it as the exit
// block and continue by adding instructions there.
DCHECK(join != NULL);
if (join->HasPredecessor()) {
set_current_block(join);
join->SetJoinId(expr->id());
if (!ast_context()->IsEffect()) return ast_context()->ReturnValue(Pop());
} else {
set_current_block(NULL);
}
}
void HOptimizedGraphBuilder::TraceInline(Handle<JSFunction> target,
Handle<JSFunction> caller,
const char* reason,
TailCallMode tail_call_mode) {
if (FLAG_trace_inlining) {
std::unique_ptr<char[]> target_name =
target->shared()->DebugName()->ToCString();
std::unique_ptr<char[]> caller_name =
caller->shared()->DebugName()->ToCString();
if (reason == NULL) {
const char* call_mode =
tail_call_mode == TailCallMode::kAllow ? "tail called" : "called";
PrintF("Inlined %s %s from %s.\n", target_name.get(), call_mode,
caller_name.get());
} else {
PrintF("Did not inline %s called from %s (%s).\n",
target_name.get(), caller_name.get(), reason);
}
}
}
static const int kNotInlinable = 1000000000;
int HOptimizedGraphBuilder::InliningAstSize(Handle<JSFunction> target) {
if (!FLAG_use_inlining) return kNotInlinable;
// Precondition: call is monomorphic and we have found a target with the
// appropriate arity.
Handle<JSFunction> caller = current_info()->closure();
Handle<SharedFunctionInfo> target_shared(target->shared());
// Always inline functions that force inlining.
if (target_shared->force_inline()) {
return 0;
}
if (!target->shared()->IsUserJavaScript()) {
return kNotInlinable;
}
if (target_shared->IsApiFunction()) {
TraceInline(target, caller, "target is api function");
return kNotInlinable;
}
// Do a quick check on source code length to avoid parsing large
// inlining candidates.
if (target_shared->SourceSize() >
Min(FLAG_max_inlined_source_size, kUnlimitedMaxInlinedSourceSize)) {
TraceInline(target, caller, "target text too big");
return kNotInlinable;
}
// Target must be inlineable.
BailoutReason noopt_reason = target_shared->disable_optimization_reason();
if (!target_shared->IsInlineable() && noopt_reason != kHydrogenFilter) {
TraceInline(target, caller, "target not inlineable");
return kNotInlinable;
}
if (noopt_reason != kNoReason && noopt_reason != kHydrogenFilter) {
TraceInline(target, caller, "target contains unsupported syntax [early]");
return kNotInlinable;
}
int nodes_added = target_shared->ast_node_count();
return nodes_added;
}
bool HOptimizedGraphBuilder::TryInline(Handle<JSFunction> target,
int arguments_count,
HValue* implicit_return_value,
BailoutId ast_id, BailoutId return_id,
InliningKind inlining_kind,
TailCallMode syntactic_tail_call_mode) {
if (target->context()->native_context() !=
top_info()->closure()->context()->native_context()) {
return false;
}
int nodes_added = InliningAstSize(target);
if (nodes_added == kNotInlinable) return false;
Handle<JSFunction> caller = current_info()->closure();
if (nodes_added > Min(FLAG_max_inlined_nodes, kUnlimitedMaxInlinedNodes)) {
TraceInline(target, caller, "target AST is too large [early]");
return false;
}
// Don't inline deeper than the maximum number of inlining levels.
HEnvironment* env = environment();
int current_level = 1;
while (env->outer() != NULL) {
if (current_level == FLAG_max_inlining_levels) {
TraceInline(target, caller, "inline depth limit reached");
return false;
}
if (env->outer()->frame_type() == JS_FUNCTION) {
current_level++;
}
env = env->outer();
}
// Don't inline recursive functions.
for (FunctionState* state = function_state();
state != NULL;
state = state->outer()) {
if (*state->compilation_info()->closure() == *target) {
TraceInline(target, caller, "target is recursive");
return false;
}
}
// We don't want to add more than a certain number of nodes from inlining.
// Always inline small methods (<= 10 nodes).
if (inlined_count_ > Min(FLAG_max_inlined_nodes_cumulative,
kUnlimitedMaxInlinedNodesCumulative)) {
TraceInline(target, caller, "cumulative AST node limit reached");
return false;
}
// Parse and allocate variables.
// Use the same AstValueFactory for creating strings in the sub-compilation
// step, but don't transfer ownership to target_info.
Handle<SharedFunctionInfo> target_shared(target->shared());
ParseInfo parse_info(target_shared, top_info()->parse_info()->zone_shared());
parse_info.set_ast_value_factory(
top_info()->parse_info()->ast_value_factory());
parse_info.set_ast_value_factory_owned(false);
CompilationInfo target_info(parse_info.zone(), &parse_info,
target->GetIsolate(), target);
if (inlining_kind != CONSTRUCT_CALL_RETURN &&
IsClassConstructor(target_shared->kind())) {
TraceInline(target, caller, "target is classConstructor");
return false;
}
if (target_shared->HasDebugInfo()) {
TraceInline(target, caller, "target is being debugged");
return false;
}
if (!Compiler::ParseAndAnalyze(&target_info)) {
if (target_info.isolate()->has_pending_exception()) {
// Parse or scope error, never optimize this function.
SetStackOverflow();
target_shared->DisableOptimization(kParseScopeError);
}
TraceInline(target, caller, "parse failure");
return false;
}
if (target_shared->must_use_ignition_turbo()) {
TraceInline(target, caller, "ParseAndAnalyze found incompatibility");
return false;
}
if (target_info.scope()->NeedsContext()) {
TraceInline(target, caller, "target has context-allocated variables");
return false;
}
if (target_info.scope()->rest_parameter() != nullptr) {
TraceInline(target, caller, "target uses rest parameters");
return false;
}
FunctionLiteral* function = target_info.literal();
// The following conditions must be checked again after re-parsing, because
// earlier the information might not have been complete due to lazy parsing.
nodes_added = function->ast_node_count();
if (nodes_added > Min(FLAG_max_inlined_nodes, kUnlimitedMaxInlinedNodes)) {
TraceInline(target, caller, "target AST is too large [late]");
return false;
}
if (function->dont_optimize()) {
TraceInline(target, caller, "target contains unsupported syntax [late]");
return false;
}
// If the function uses the arguments object check that inlining of functions
// with arguments object is enabled and the arguments-variable is
// stack allocated.
if (function->scope()->arguments() != NULL) {
if (!FLAG_inline_arguments) {
TraceInline(target, caller, "target uses arguments object");
return false;
}
}
// Unsupported variable references present.
if (function->scope()->this_function_var() != nullptr ||
function->scope()->new_target_var() != nullptr) {
TraceInline(target, caller, "target uses new target or this function");
return false;
}
// All declarations must be inlineable.
Declaration::List* decls = target_info.scope()->declarations();
for (Declaration* decl : *decls) {
if (decl->IsFunctionDeclaration() ||
!decl->proxy()->var()->IsStackAllocated()) {
TraceInline(target, caller, "target has non-trivial declaration");
return false;
}
}
// Generate the deoptimization data for the unoptimized version of
// the target function if we don't already have it.
if (!Compiler::EnsureDeoptimizationSupport(&target_info)) {
TraceInline(target, caller, "could not generate deoptimization info");
return false;
}
// Remember that we inlined this function. This needs to be called right
// after the EnsureDeoptimizationSupport call so that the code flusher
// does not remove the code with the deoptimization support.
int inlining_id = top_info()->AddInlinedFunction(target_info.shared_info(),
source_position());
// ----------------------------------------------------------------
// After this point, we've made a decision to inline this function (so
// TryInline should always return true).
// If target was lazily compiled, it's literals array may not yet be set up.
JSFunction::EnsureLiterals(target);
// Type-check the inlined function.
DCHECK(target_shared->has_deoptimization_support());
AstTyper(target_info.isolate(), target_info.zone(), target_info.closure(),
target_info.scope(), target_info.osr_ast_id(), target_info.literal(),
&bounds_)
.Run();
// Save the pending call context. Set up new one for the inlined function.
// The function state is new-allocated because we need to delete it
// in two different places.
FunctionState* target_state = new FunctionState(
this, &target_info, inlining_kind, inlining_id,
function_state()->ComputeTailCallMode(syntactic_tail_call_mode));
HConstant* undefined = graph()->GetConstantUndefined();
HEnvironment* inner_env = environment()->CopyForInlining(
target, arguments_count, function, undefined,
function_state()->inlining_kind(), syntactic_tail_call_mode);
HConstant* context = Add<HConstant>(Handle<Context>(target->context()));
inner_env->BindContext(context);
// Create a dematerialized arguments object for the function, also copy the
// current arguments values to use them for materialization.
HEnvironment* arguments_env = inner_env->arguments_environment();
int parameter_count = arguments_env->parameter_count();
HArgumentsObject* arguments_object = Add<HArgumentsObject>(parameter_count);
for (int i = 0; i < parameter_count; i++) {
arguments_object->AddArgument(arguments_env->Lookup(i), zone());
}
// If the function uses arguments object then bind bind one.
if (function->scope()->arguments() != NULL) {
DCHECK(function->scope()->arguments()->IsStackAllocated());
inner_env->Bind(function->scope()->arguments(), arguments_object);
}
// Capture the state before invoking the inlined function for deopt in the
// inlined function. This simulate has no bailout-id since it's not directly
// reachable for deopt, and is only used to capture the state. If the simulate
// becomes reachable by merging, the ast id of the simulate merged into it is
// adopted.
Add<HSimulate>(BailoutId::None());
current_block()->UpdateEnvironment(inner_env);
Scope* saved_scope = scope();
set_scope(target_info.scope());
HEnterInlined* enter_inlined = Add<HEnterInlined>(
return_id, target, context, arguments_count, function,
function_state()->inlining_kind(), function->scope()->arguments(),
arguments_object, syntactic_tail_call_mode);
if (is_tracking_positions()) {
enter_inlined->set_inlining_id(inlining_id);
}
function_state()->set_entry(enter_inlined);
VisitDeclarations(target_info.scope()->declarations());
VisitStatements(function->body());
set_scope(saved_scope);
if (HasStackOverflow()) {
// Bail out if the inline function did, as we cannot residualize a call
// instead, but do not disable optimization for the outer function.
TraceInline(target, caller, "inline graph construction failed");
target_shared->DisableOptimization(kInliningBailedOut);
current_info()->RetryOptimization(kInliningBailedOut);
delete target_state;
return true;
}
// Update inlined nodes count.
inlined_count_ += nodes_added;
Handle<Code> unoptimized_code(target_shared->code());
DCHECK(unoptimized_code->kind() == Code::FUNCTION);
Handle<TypeFeedbackInfo> type_info(
TypeFeedbackInfo::cast(unoptimized_code->type_feedback_info()));
graph()->update_type_change_checksum(type_info->own_type_change_checksum());
TraceInline(target, caller, NULL, syntactic_tail_call_mode);
if (current_block() != NULL) {
FunctionState* state = function_state();
if (state->inlining_kind() == CONSTRUCT_CALL_RETURN) {
// Falling off the end of an inlined construct call. In a test context the
// return value will always evaluate to true, in a value context the
// return value is the newly allocated receiver.
if (call_context()->IsTest()) {
inlined_test_context()->ReturnValue(graph()->GetConstantTrue());
} else if (call_context()->IsEffect()) {
Goto(function_return(), state);
} else {
DCHECK(call_context()->IsValue());
AddLeaveInlined(implicit_return_value, state);
}
} else if (state->inlining_kind() == SETTER_CALL_RETURN) {
// Falling off the end of an inlined setter call. The returned value is
// never used, the value of an assignment is always the value of the RHS
// of the assignment.
if (call_context()->IsTest()) {
inlined_test_context()->ReturnValue(implicit_return_value);
} else if (call_context()->IsEffect()) {
Goto(function_return(), state);
} else {
DCHECK(call_context()->IsValue());
AddLeaveInlined(implicit_return_value, state);
}
} else {
// Falling off the end of a normal inlined function. This basically means
// returning undefined.
if (call_context()->IsTest()) {
inlined_test_context()->ReturnValue(graph()->GetConstantFalse());
} else if (call_context()->IsEffect()) {
Goto(function_return(), state);
} else {
DCHECK(call_context()->IsValue());
AddLeaveInlined(undefined, state);
}
}
}
// Fix up the function exits.
if (inlined_test_context() != NULL) {
HBasicBlock* if_true = inlined_test_context()->if_true();
HBasicBlock* if_false = inlined_test_context()->if_false();
HEnterInlined* entry = function_state()->entry();
// Pop the return test context from the expression context stack.
DCHECK(ast_context() == inlined_test_context());
ClearInlinedTestContext();
delete target_state;
// Forward to the real test context.
if (if_true->HasPredecessor()) {
entry->RegisterReturnTarget(if_true, zone());
if_true->SetJoinId(ast_id);
HBasicBlock* true_target = TestContext::cast(ast_context())->if_true();
Goto(if_true, true_target, function_state());
}
if (if_false->HasPredecessor()) {
entry->RegisterReturnTarget(if_false, zone());
if_false->SetJoinId(ast_id);
HBasicBlock* false_target = TestContext::cast(ast_context())->if_false();
Goto(if_false, false_target, function_state());
}
set_current_block(NULL);
return true;
} else if (function_return()->HasPredecessor()) {
function_state()->entry()->RegisterReturnTarget(function_return(), zone());
function_return()->SetJoinId(ast_id);
set_current_block(function_return());
} else {
set_current_block(NULL);
}
delete target_state;
return true;
}
bool HOptimizedGraphBuilder::TryInlineCall(Call* expr) {
return TryInline(expr->target(), expr->arguments()->length(), NULL,
expr->id(), expr->ReturnId(), NORMAL_RETURN,
expr->tail_call_mode());
}
bool HOptimizedGraphBuilder::TryInlineConstruct(CallNew* expr,
HValue* implicit_return_value) {
return TryInline(expr->target(), expr->arguments()->length(),
implicit_return_value, expr->id(), expr->ReturnId(),
CONSTRUCT_CALL_RETURN, TailCallMode::kDisallow);
}
bool HOptimizedGraphBuilder::TryInlineGetter(Handle<Object> getter,
Handle<Map> receiver_map,
BailoutId ast_id,
BailoutId return_id) {
if (TryInlineApiGetter(getter, receiver_map, ast_id)) return true;
if (getter->IsJSFunction()) {
Handle<JSFunction> getter_function = Handle<JSFunction>::cast(getter);
return TryInlineBuiltinGetterCall(getter_function, receiver_map, ast_id) ||
TryInline(getter_function, 0, NULL, ast_id, return_id,
GETTER_CALL_RETURN, TailCallMode::kDisallow);
}
return false;
}
bool HOptimizedGraphBuilder::TryInlineSetter(Handle<Object> setter,
Handle<Map> receiver_map,
BailoutId id,
BailoutId assignment_id,
HValue* implicit_return_value) {
if (TryInlineApiSetter(setter, receiver_map, id)) return true;
return setter->IsJSFunction() &&
TryInline(Handle<JSFunction>::cast(setter), 1, implicit_return_value,
id, assignment_id, SETTER_CALL_RETURN,
TailCallMode::kDisallow);
}
bool HOptimizedGraphBuilder::TryInlineIndirectCall(Handle<JSFunction> function,
Call* expr,
int arguments_count) {
return TryInline(function, arguments_count, NULL, expr->id(),
expr->ReturnId(), NORMAL_RETURN, expr->tail_call_mode());
}
bool HOptimizedGraphBuilder::TryInlineBuiltinFunctionCall(Call* expr) {
if (!expr->target()->shared()->HasBuiltinFunctionId()) return false;
BuiltinFunctionId id = expr->target()->shared()->builtin_function_id();
// We intentionally ignore expr->tail_call_mode() here because builtins
// we inline here do not observe if they were tail called or not.
switch (id) {
case kMathCos:
case kMathExp:
case kMathRound:
case kMathFround:
case kMathFloor:
case kMathAbs:
case kMathSin:
case kMathSqrt:
case kMathLog:
case kMathClz32:
if (expr->arguments()->length() == 1) {
HValue* argument = Pop();
Drop(2); // Receiver and function.
HInstruction* op = NewUncasted<HUnaryMathOperation>(argument, id);
ast_context()->ReturnInstruction(op, expr->id());
return true;
}
break;
case kMathImul:
if (expr->arguments()->length() == 2) {
HValue* right = Pop();
HValue* left = Pop();
Drop(2); // Receiver and function.
HInstruction* op =
HMul::NewImul(isolate(), zone(), context(), left, right);
ast_context()->ReturnInstruction(op, expr->id());
return true;
}
break;
default:
// Not supported for inlining yet.
break;
}
return false;
}
// static
bool HOptimizedGraphBuilder::IsReadOnlyLengthDescriptor(
Handle<Map> jsarray_map) {
DCHECK(!jsarray_map->is_dictionary_map());
Isolate* isolate = jsarray_map->GetIsolate();
Handle<Name> length_string = isolate->factory()->length_string();
DescriptorArray* descriptors = jsarray_map->instance_descriptors();
int number =
descriptors->SearchWithCache(isolate, *length_string, *jsarray_map);
DCHECK_NE(DescriptorArray::kNotFound, number);
return descriptors->GetDetails(number).IsReadOnly();
}
// static
bool HOptimizedGraphBuilder::CanInlineArrayResizeOperation(
Handle<Map> receiver_map) {
return !receiver_map.is_null() && receiver_map->prototype()->IsJSObject() &&
receiver_map->instance_type() == JS_ARRAY_TYPE &&
IsFastElementsKind(receiver_map->elements_kind()) &&
!receiver_map->is_dictionary_map() && receiver_map->is_extensible() &&
(!receiver_map->is_prototype_map() || receiver_map->is_stable()) &&
!IsReadOnlyLengthDescriptor(receiver_map);
}
bool HOptimizedGraphBuilder::TryInlineBuiltinGetterCall(
Handle<JSFunction> function, Handle<Map> receiver_map, BailoutId ast_id) {
if (!function->shared()->HasBuiltinFunctionId()) return false;
BuiltinFunctionId id = function->shared()->builtin_function_id();
// Try to inline getter calls like DataView.prototype.byteLength/byteOffset
// as operations in the calling function.
switch (id) {
case kDataViewBuffer: {
if (!receiver_map->IsJSDataViewMap()) return false;
HObjectAccess access = HObjectAccess::ForMapAndOffset(
receiver_map, JSDataView::kBufferOffset);
HValue* object = Pop(); // receiver
HInstruction* result = New<HLoadNamedField>(object, object, access);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
case kDataViewByteLength:
case kDataViewByteOffset: {
if (!receiver_map->IsJSDataViewMap()) return false;
int offset = (id == kDataViewByteLength) ? JSDataView::kByteLengthOffset
: JSDataView::kByteOffsetOffset;
HObjectAccess access =
HObjectAccess::ForMapAndOffset(receiver_map, offset);
HValue* object = Pop(); // receiver
HValue* checked_object = Add<HCheckArrayBufferNotNeutered>(object);
HInstruction* result =
New<HLoadNamedField>(object, checked_object, access);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
case kTypedArrayByteLength:
case kTypedArrayByteOffset:
case kTypedArrayLength: {
if (!receiver_map->IsJSTypedArrayMap()) return false;
int offset = (id == kTypedArrayLength)
? JSTypedArray::kLengthOffset
: (id == kTypedArrayByteLength)
? JSTypedArray::kByteLengthOffset
: JSTypedArray::kByteOffsetOffset;
HObjectAccess access =
HObjectAccess::ForMapAndOffset(receiver_map, offset);
HValue* object = Pop(); // receiver
HValue* checked_object = Add<HCheckArrayBufferNotNeutered>(object);
HInstruction* result =
New<HLoadNamedField>(object, checked_object, access);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
default:
return false;
}
}
// static
bool HOptimizedGraphBuilder::NoElementsInPrototypeChain(
Handle<Map> receiver_map) {
// TODO(ishell): remove this once we support NO_ELEMENTS elements kind.
PrototypeIterator iter(receiver_map);
Handle<Object> empty_fixed_array =
iter.isolate()->factory()->empty_fixed_array();
while (true) {
Handle<JSObject> current = PrototypeIterator::GetCurrent<JSObject>(iter);
if (current->elements() != *empty_fixed_array) return false;
iter.Advance();
if (iter.IsAtEnd()) {
return true;
}
}
}
bool HOptimizedGraphBuilder::TryInlineBuiltinMethodCall(
Handle<JSFunction> function, Handle<Map> receiver_map, BailoutId ast_id,
int args_count_no_receiver) {
if (!function->shared()->HasBuiltinFunctionId()) return false;
BuiltinFunctionId id = function->shared()->builtin_function_id();
int argument_count = args_count_no_receiver + 1; // Plus receiver.
if (receiver_map.is_null()) {
HValue* receiver = environment()->ExpressionStackAt(args_count_no_receiver);
if (receiver->IsConstant() &&
HConstant::cast(receiver)->handle(isolate())->IsHeapObject()) {
receiver_map =
handle(Handle<HeapObject>::cast(
HConstant::cast(receiver)->handle(isolate()))->map());
}
}
// Try to inline calls like Math.* as operations in the calling function.
switch (id) {
case kObjectHasOwnProperty: {
// It's not safe to look through the phi for elements if we're compiling
// for osr.
if (top_info()->is_osr()) return false;
if (argument_count != 2) return false;
HValue* key = Top();
if (!key->IsLoadKeyed()) return false;
HValue* elements = HLoadKeyed::cast(key)->elements();
if (!elements->IsPhi() || elements->OperandCount() != 1) return false;
if (!elements->OperandAt(0)->IsForInCacheArray()) return false;
HForInCacheArray* cache = HForInCacheArray::cast(elements->OperandAt(0));
HValue* receiver = environment()->ExpressionStackAt(1);
if (!receiver->IsPhi() || receiver->OperandCount() != 1) return false;
if (cache->enumerable() != receiver->OperandAt(0)) return false;
Drop(3); // key, receiver, function
Add<HCheckMapValue>(receiver, cache->map());
ast_context()->ReturnValue(graph()->GetConstantTrue());
return true;
}
case kStringCharCodeAt:
case kStringCharAt:
if (argument_count == 2) {
HValue* index = Pop();
HValue* string = Pop();
Drop(1); // Function.
HInstruction* char_code =
BuildStringCharCodeAt(string, index);
if (id == kStringCharCodeAt) {
ast_context()->ReturnInstruction(char_code, ast_id);
return true;
}
AddInstruction(char_code);
HInstruction* result = NewUncasted<HStringCharFromCode>(char_code);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
break;
case kStringFromCharCode:
if (argument_count == 2) {
HValue* argument = Pop();
Drop(2); // Receiver and function.
argument = AddUncasted<HForceRepresentation>(
argument, Representation::Integer32());
argument->SetFlag(HValue::kTruncatingToInt32);
HInstruction* result = NewUncasted<HStringCharFromCode>(argument);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
break;
case kMathCos:
case kMathExp:
case kMathRound:
case kMathFround:
case kMathFloor:
case kMathAbs:
case kMathSin:
case kMathSqrt:
case kMathLog:
case kMathClz32:
if (argument_count == 2) {
HValue* argument = Pop();
Drop(2); // Receiver and function.
HInstruction* op = NewUncasted<HUnaryMathOperation>(argument, id);
ast_context()->ReturnInstruction(op, ast_id);
return true;
}
break;
case kMathPow:
if (argument_count == 3) {
HValue* right = Pop();
HValue* left = Pop();
Drop(2); // Receiver and function.
HInstruction* result = NULL;
// Use sqrt() if exponent is 0.5 or -0.5.
if (right->IsConstant() && HConstant::cast(right)->HasDoubleValue()) {
double exponent = HConstant::cast(right)->DoubleValue();
if (exponent == 0.5) {
result = NewUncasted<HUnaryMathOperation>(left, kMathPowHalf);
} else if (exponent == -0.5) {
HValue* one = graph()->GetConstant1();
HInstruction* sqrt = AddUncasted<HUnaryMathOperation>(
left, kMathPowHalf);
// MathPowHalf doesn't have side effects so there's no need for
// an environment simulation here.
DCHECK(!sqrt->HasObservableSideEffects());
result = NewUncasted<HDiv>(one, sqrt);
} else if (exponent == 2.0) {
result = NewUncasted<HMul>(left, left);
}
}
if (result == NULL) {
result = NewUncasted<HPower>(left, right);
}
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
break;
case kMathMax:
case kMathMin:
if (argument_count == 3) {
HValue* right = Pop();
HValue* left = Pop();
Drop(2); // Receiver and function.
HMathMinMax::Operation op = (id == kMathMin) ? HMathMinMax::kMathMin
: HMathMinMax::kMathMax;
HInstruction* result = NewUncasted<HMathMinMax>(left, right, op);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
break;
case kMathImul:
if (argument_count == 3) {
HValue* right = Pop();
HValue* left = Pop();
Drop(2); // Receiver and function.
HInstruction* result =
HMul::NewImul(isolate(), zone(), context(), left, right);
ast_context()->ReturnInstruction(result, ast_id);
return true;
}
break;
case kArrayPop: {
if (!CanInlineArrayResizeOperation(receiver_map)) return false;
ElementsKind elements_kind = receiver_map->elements_kind();
Drop(args_count_no_receiver);
HValue* result;
HValue* reduced_length;
HValue* receiver = Pop();
HValue* checked_object = AddCheckMap(receiver, receiver_map);
HValue* length =
Add<HLoadNamedField>(checked_object, nullptr,
HObjectAccess::ForArrayLength(elements_kind));
Drop(1); // Function.
{ NoObservableSideEffectsScope scope(this);
IfBuilder length_checker(this);
HValue* bounds_check = length_checker.If<HCompareNumericAndBranch>(
length, graph()->GetConstant0(), Token::EQ);
length_checker.Then();
if (!ast_context()->IsEffect()) Push(graph()->GetConstantUndefined());
length_checker.Else();
HValue* elements = AddLoadElements(checked_object);
// Ensure that we aren't popping from a copy-on-write array.
if (IsFastSmiOrObjectElementsKind(elements_kind)) {
elements = BuildCopyElementsOnWrite(checked_object, elements,
elements_kind, length);
}
reduced_length = AddUncasted<HSub>(length, graph()->GetConstant1());
result = AddElementAccess(elements, reduced_length, nullptr,
bounds_check, nullptr, elements_kind, LOAD);
HValue* hole = IsFastSmiOrObjectElementsKind(elements_kind)
? graph()->GetConstantHole()
: Add<HConstant>(HConstant::kHoleNaN);
if (IsFastSmiOrObjectElementsKind(elements_kind)) {
elements_kind = FAST_HOLEY_ELEMENTS;
}
AddElementAccess(elements, reduced_length, hole, bounds_check, nullptr,
elements_kind, STORE);
Add<HStoreNamedField>(
checked_object, HObjectAccess::ForArrayLength(elements_kind),
reduced_length, STORE_TO_INITIALIZED_ENTRY);
if (!ast_context()->IsEffect()) Push(result);
length_checker.End();
}
result = ast_context()->IsEffect() ? graph()->GetConstant0() : Top();
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) Drop(1);
ast_context()->ReturnValue(result);
return true;
}
case kArrayPush: {
if (!CanInlineArrayResizeOperation(receiver_map)) return false;
ElementsKind elements_kind = receiver_map->elements_kind();
// If there may be elements accessors in the prototype chain, the fast
// inlined version can't be used.
if (receiver_map->DictionaryElementsInPrototypeChainOnly()) return false;
// If there currently can be no elements accessors on the prototype chain,
// it doesn't mean that there won't be any later. Install a full prototype
// chain check to trap element accessors being installed on the prototype
// chain, which would cause elements to go to dictionary mode and result
// in a map change.
Handle<JSObject> prototype(JSObject::cast(receiver_map->prototype()));
BuildCheckPrototypeMaps(prototype, Handle<JSObject>());
// Protect against adding elements to the Array prototype, which needs to
// route through appropriate bottlenecks.
if (isolate()->IsFastArrayConstructorPrototypeChainIntact() &&
!prototype->IsJSArray()) {
return false;
}
const int argc = args_count_no_receiver;
if (argc != 1) return false;
HValue* value_to_push = Pop();
HValue* array = Pop();
Drop(1); // Drop function.
HInstruction* new_size = NULL;
HValue* length = NULL;
{
NoObservableSideEffectsScope scope(this);
length = Add<HLoadNamedField>(
array, nullptr, HObjectAccess::ForArrayLength(elements_kind));
new_size = AddUncasted<HAdd>(length, graph()->GetConstant1());
bool is_array = receiver_map->instance_type() == JS_ARRAY_TYPE;
HValue* checked_array = Add<HCheckMaps>(array, receiver_map);
BuildUncheckedMonomorphicElementAccess(
checked_array, length, value_to_push, is_array, elements_kind,
STORE, NEVER_RETURN_HOLE, STORE_AND_GROW_NO_TRANSITION);
if (!ast_context()->IsEffect()) Push(new_size);
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) Drop(1);
}
ast_context()->ReturnValue(new_size);
return true;
}
case kArrayShift: {
if (!CanInlineArrayResizeOperation(receiver_map)) return false;
if (!NoElementsInPrototypeChain(receiver_map)) return false;
ElementsKind kind = receiver_map->elements_kind();
// If there may be elements accessors in the prototype chain, the fast
// inlined version can't be used.
if (receiver_map->DictionaryElementsInPrototypeChainOnly()) return false;
// If there currently can be no elements accessors on the prototype chain,
// it doesn't mean that there won't be any later. Install a full prototype
// chain check to trap element accessors being installed on the prototype
// chain, which would cause elements to go to dictionary mode and result
// in a map change.
BuildCheckPrototypeMaps(
handle(JSObject::cast(receiver_map->prototype()), isolate()),
Handle<JSObject>::null(), true);
// Threshold for fast inlined Array.shift().
HConstant* inline_threshold = Add<HConstant>(JSArray::kMaxCopyElements);
Drop(args_count_no_receiver);
HValue* result;
HValue* receiver = Pop();
HValue* checked_object = AddCheckMap(receiver, receiver_map);
HValue* length = Add<HLoadNamedField>(
receiver, checked_object, HObjectAccess::ForArrayLength(kind));
Drop(1); // Function.
{
NoObservableSideEffectsScope scope(this);
IfBuilder if_lengthiszero(this);
HValue* lengthiszero = if_lengthiszero.If<HCompareNumericAndBranch>(
length, graph()->GetConstant0(), Token::EQ);
if_lengthiszero.Then();
{
if (!ast_context()->IsEffect()) Push(graph()->GetConstantUndefined());
}
if_lengthiszero.Else();
{
HValue* elements = AddLoadElements(receiver);
// Check if we can use the fast inlined Array.shift().
IfBuilder if_inline(this);
if_inline.If<HCompareNumericAndBranch>(
length, inline_threshold, Token::LTE);
if (IsFastSmiOrObjectElementsKind(kind)) {
// We cannot handle copy-on-write backing stores here.
if_inline.AndIf<HCompareMap>(
elements, isolate()->factory()->fixed_array_map());
}
if_inline.Then();
{
// Remember the result.
if (!ast_context()->IsEffect()) {
Push(AddElementAccess(elements, graph()->GetConstant0(), nullptr,
lengthiszero, nullptr, kind, LOAD));
}
// Compute the new length.
HValue* new_length = AddUncasted<HSub>(
length, graph()->GetConstant1());
new_length->ClearFlag(HValue::kCanOverflow);
// Copy the remaining elements.
LoopBuilder loop(this, context(), LoopBuilder::kPostIncrement);
{
HValue* new_key = loop.BeginBody(
graph()->GetConstant0(), new_length, Token::LT);
HValue* key = AddUncasted<HAdd>(new_key, graph()->GetConstant1());
key->ClearFlag(HValue::kCanOverflow);
ElementsKind copy_kind =
kind == FAST_HOLEY_SMI_ELEMENTS ? FAST_HOLEY_ELEMENTS : kind;
HValue* element =
AddUncasted<HLoadKeyed>(elements, key, lengthiszero, nullptr,
copy_kind, ALLOW_RETURN_HOLE);
HStoreKeyed* store = Add<HStoreKeyed>(elements, new_key, element,
nullptr, copy_kind);
store->SetFlag(HValue::kTruncatingToNumber);
}
loop.EndBody();
// Put a hole at the end.
HValue* hole = IsFastSmiOrObjectElementsKind(kind)
? graph()->GetConstantHole()
: Add<HConstant>(HConstant::kHoleNaN);
if (IsFastSmiOrObjectElementsKind(kind)) kind = FAST_HOLEY_ELEMENTS;
Add<HStoreKeyed>(elements, new_length, hole, nullptr, kind,
INITIALIZING_STORE);
// Remember new length.
Add<HStoreNamedField>(
receiver, HObjectAccess::ForArrayLength(kind),
new_length, STORE_TO_INITIALIZED_ENTRY);
}
if_inline.Else();
{
Add<HPushArguments>(receiver);
result = AddInstruction(NewCallConstantFunction(
function, 1, TailCallMode::kDisallow, TailCallMode::kDisallow));
if (!ast_context()->IsEffect()) Push(result);
}
if_inline.End();
}
if_lengthiszero.End();
}
result = ast_context()->IsEffect() ? graph()->GetConstant0() : Top();
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) Drop(1);
ast_context()->ReturnValue(result);
return true;
}
case kArrayIndexOf:
case kArrayLastIndexOf: {
if (receiver_map.is_null()) return false;
if (receiver_map->instance_type() != JS_ARRAY_TYPE) return false;
if (!receiver_map->prototype()->IsJSObject()) return false;
ElementsKind kind = receiver_map->elements_kind();
if (!IsFastElementsKind(kind)) return false;
if (argument_count != 2) return false;
if (!receiver_map->is_extensible()) return false;
// If there may be elements accessors in the prototype chain, the fast
// inlined version can't be used.
if (receiver_map->DictionaryElementsInPrototypeChainOnly()) return false;
// If there currently can be no elements accessors on the prototype chain,
// it doesn't mean that there won't be any later. Install a full prototype
// chain check to trap element accessors being installed on the prototype
// chain, which would cause elements to go to dictionary mode and result
// in a map change.
BuildCheckPrototypeMaps(
handle(JSObject::cast(receiver_map->prototype()), isolate()),
Handle<JSObject>::null());
HValue* search_element = Pop();
HValue* receiver = Pop();
Drop(1); // Drop function.
ArrayIndexOfMode mode = (id == kArrayIndexOf)
? kFirstIndexOf : kLastIndexOf;
HValue* index = BuildArrayIndexOf(receiver, search_element, kind, mode);
if (!ast_context()->IsEffect()) Push(index);
Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) Drop(1);
ast_context()->ReturnValue(index);
return true;
}
default:
// Not yet supported for inlining.
break;
}
return false;
}
bool HOptimizedGraphBuilder::TryInlineApiFunctionCall(Call* expr,
HValue* receiver) {
if (V8_UNLIKELY(FLAG_runtime_stats)) return false;
Handle<JSFunction> function = expr->target();
int argc = expr->arguments()->length();
SmallMapList receiver_maps;
return TryInlineApiCall(function, receiver, &receiver_maps, argc, expr->id(),
kCallApiFunction, expr->tail_call_mode());
}
bool HOptimizedGraphBuilder::TryInlineApiMethodCall(
Call* expr,
HValue* receiver,
SmallMapList* receiver_maps) {
if (V8_UNLIKELY(FLAG_runtime_stats)) return false;
Handle<JSFunction> function = expr->target();
int argc = expr->arguments()->length();
return TryInlineApiCall(function, receiver, receiver_maps, argc, expr->id(),
kCallApiMethod, expr->tail_call_mode());
}
bool HOptimizedGraphBuilder::TryInlineApiGetter(Handle<Object> function,
Handle<Map> receiver_map,
BailoutId ast_id) {
if (V8_UNLIKELY(FLAG_runtime_stats)) return false;
SmallMapList receiver_maps(1, zone());
receiver_maps.Add(receiver_map, zone());
return TryInlineApiCall(function,
NULL, // Receiver is on expression stack.
&receiver_maps, 0, ast_id, kCallApiGetter,
TailCallMode::kDisallow);
}
bool HOptimizedGraphBuilder::TryInlineApiSetter(Handle<Object> function,
Handle<Map> receiver_map,
BailoutId ast_id) {
SmallMapList receiver_maps(1, zone());
receiver_maps.Add(receiver_map, zone());
return TryInlineApiCall(function,
NULL, // Receiver is on expression stack.
&receiver_maps, 1, ast_id, kCallApiSetter,
TailCallMode::kDisallow);
}
bool HOptimizedGraphBuilder::TryInlineApiCall(
Handle<Object> function, HValue* receiver, SmallMapList* receiver_maps,
int argc, BailoutId ast_id, ApiCallType call_type,
TailCallMode syntactic_tail_call_mode) {
if (V8_UNLIKELY(FLAG_runtime_stats)) return false;
if (function->IsJSFunction() &&
Handle<JSFunction>::cast(function)->context()->native_context() !=
top_info()->closure()->context()->native_context()) {
return false;
}
if (argc > CallApiCallbackStub::kArgMax) {
return false;
}
CallOptimization optimization(function);
if (!optimization.is_simple_api_call()) return false;
Handle<Map> holder_map;
for (int i = 0; i < receiver_maps->length(); ++i) {
auto map = receiver_maps->at(i);
// Don't inline calls to receivers requiring accesschecks.
if (map->is_access_check_needed()) return false;
}
if (call_type == kCallApiFunction) {
// Cannot embed a direct reference to the global proxy map
// as it maybe dropped on deserialization.
CHECK(!isolate()->serializer_enabled());
DCHECK(function->IsJSFunction());
DCHECK_EQ(0, receiver_maps->length());
receiver_maps->Add(
handle(Handle<JSFunction>::cast(function)->global_proxy()->map()),
zone());
}
CallOptimization::HolderLookup holder_lookup =
CallOptimization::kHolderNotFound;
Handle<JSObject> api_holder = optimization.LookupHolderOfExpectedType(
receiver_maps->first(), &holder_lookup);
if (holder_lookup == CallOptimization::kHolderNotFound) return false;
if (FLAG_trace_inlining) {
PrintF("Inlining api function ");
function->ShortPrint();
PrintF("\n");
}
bool is_function = false;
bool is_store = false;
switch (call_type) {
case kCallApiFunction:
case kCallApiMethod:
// Need to check that none of the receiver maps could have changed.
Add<HCheckMaps>(receiver, receiver_maps);
// Need to ensure the chain between receiver and api_holder is intact.
if (holder_lookup == CallOptimization::kHolderFound) {
AddCheckPrototypeMaps(api_holder, receiver_maps->first());
} else {
DCHECK_EQ(holder_lookup, CallOptimization::kHolderIsReceiver);
}
// Includes receiver.
PushArgumentsFromEnvironment(argc + 1);
is_function = true;
break;
case kCallApiGetter:
// Receiver and prototype chain cannot have changed.
DCHECK_EQ(0, argc);
DCHECK_NULL(receiver);
// Receiver is on expression stack.
receiver = Pop();
Add<HPushArguments>(receiver);
break;
case kCallApiSetter:
{
is_store = true;
// Receiver and prototype chain cannot have changed.
DCHECK_EQ(1, argc);
DCHECK_NULL(receiver);
// Receiver and value are on expression stack.
HValue* value = Pop();
receiver = Pop();
Add<HPushArguments>(receiver, value);
break;
}
}
HValue* holder = NULL;
switch (holder_lookup) {
case CallOptimization::kHolderFound:
holder = Add<HConstant>(api_holder);
break;
case CallOptimization::kHolderIsReceiver:
holder = receiver;
break;
case CallOptimization::kHolderNotFound:
UNREACHABLE();
break;
}
Handle<CallHandlerInfo> api_call_info = optimization.api_call_info();
Handle<Object> call_data_obj(api_call_info->data(), isolate());
HValue* call_data = Add<HConstant>(call_data_obj);
ApiFunction fun(v8::ToCData<Address>(api_call_info->callback()));
ExternalReference ref = ExternalReference(&fun,
ExternalReference::DIRECT_API_CALL,
isolate());
HValue* api_function_address = Add<HConstant>(ExternalReference(ref));
HValue* op_vals[] = {Add<HConstant>(function), call_data, holder,
api_function_address};
HInstruction* call = nullptr;
CHECK(argc <= CallApiCallbackStub::kArgMax);
if (!is_function) {
CallApiCallbackStub stub(isolate(), is_store,
!optimization.is_constant_call());
Handle<Code> code = stub.GetCode();
HConstant* code_value = Add<HConstant>(code);
call = New<HCallWithDescriptor>(
code_value, argc + 1, stub.GetCallInterfaceDescriptor(),
Vector<HValue*>(op_vals, arraysize(op_vals)), syntactic_tail_call_mode);
} else {
CallApiCallbackStub stub(isolate(), argc, false);
Handle<Code> code = stub.GetCode();
HConstant* code_value = Add<HConstant>(code);
call = New<HCallWithDescriptor>(
code_value, argc + 1, stub.GetCallInterfaceDescriptor(),
Vector<HValue*>(op_vals, arraysize(op_vals)), syntactic_tail_call_mode);
Drop(1); // Drop function.
}
ast_context()->ReturnInstruction(call, ast_id);
return true;
}
void HOptimizedGraphBuilder::HandleIndirectCall(Call* expr, HValue* function,
int arguments_count) {
Handle<JSFunction> known_function;
int args_count_no_receiver = arguments_count - 1;
if (function->IsConstant() &&
HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
known_function =
Handle<JSFunction>::cast(HConstant::cast(function)->handle(isolate()));
if (TryInlineBuiltinMethodCall(known_function, Handle<Map>(), expr->id(),
args_count_no_receiver)) {
if (FLAG_trace_inlining) {
PrintF("Inlining builtin ");
known_function->ShortPrint();
PrintF("\n");
}
return;
}
if (TryInlineIndirectCall(known_function, expr, args_count_no_receiver)) {
return;
}
}
TailCallMode syntactic_tail_call_mode = expr->tail_call_mode();
TailCallMode tail_call_mode =
function_state()->ComputeTailCallMode(syntactic_tail_call_mode);
PushArgumentsFromEnvironment(arguments_count);
HInvokeFunction* call =
New<HInvokeFunction>(function, known_function, arguments_count,
syntactic_tail_call_mode, tail_call_mode);
Drop(1); // Function
ast_context()->ReturnInstruction(call, expr->id());
}
bool HOptimizedGraphBuilder::TryIndirectCall(Call* expr) {
DCHECK(expr->expression()->IsProperty());
if (!expr->IsMonomorphic()) {
return false;
}
Handle<Map> function_map = expr->GetReceiverTypes()->first();
if (function_map->instance_type() != JS_FUNCTION_TYPE ||
!expr->target()->shared()->HasBuiltinFunctionId()) {
return false;
}
switch (expr->target()->shared()->builtin_function_id()) {
case kFunctionCall: {
if (expr->arguments()->length() == 0) return false;
BuildFunctionCall(expr);
return true;
}
case kFunctionApply: {
// For .apply, only the pattern f.apply(receiver, arguments)
// is supported.
if (!CanBeFunctionApplyArguments(expr)) return false;
BuildFunctionApply(expr);
return true;
}
default: { return false; }
}
UNREACHABLE();
}
// f.apply(...)
void HOptimizedGraphBuilder::BuildFunctionApply(Call* expr) {
ZoneList<Expression*>* args = expr->arguments();
CHECK_ALIVE(VisitForValue(args->at(0)));
HValue* receiver = Pop(); // receiver
HValue* function = Pop(); // f
Drop(1); // apply
// Make sure the arguments object is live.
VariableProxy* arg_two = args->at(1)->AsVariableProxy();
LookupAndMakeLive(arg_two->var());
Handle<Map> function_map = expr->GetReceiverTypes()->first();
HValue* checked_function = AddCheckMap(function, function_map);
if (function_state()->outer() == NULL) {
TailCallMode syntactic_tail_call_mode = expr->tail_call_mode();
TailCallMode tail_call_mode =
function_state()->ComputeTailCallMode(syntactic_tail_call_mode);
HInstruction* elements = Add<HArgumentsElements>(false);
HInstruction* length = Add<HArgumentsLength>(elements);
HValue* wrapped_receiver = BuildWrapReceiver(receiver, checked_function);
HInstruction* result = New<HApplyArguments>(
function, wrapped_receiver, length, elements, tail_call_mode);
ast_context()->ReturnInstruction(result, expr->id());
} else {
// We are inside inlined function and we know exactly what is inside
// arguments object. But we need to be able to materialize at deopt.
DCHECK_EQ(environment()->arguments_environment()->parameter_count(),
function_state()->entry()->arguments_object()->arguments_count());
HArgumentsObject* args = function_state()->entry()->arguments_object();
const ZoneList<HValue*>* arguments_values = args->arguments_values();
int arguments_count = arguments_values->length();
Push(function);
Push(BuildWrapReceiver(receiver, checked_function));
for (int i = 1; i < arguments_count; i++) {
Push(arguments_values->at(i));
}
HandleIndirectCall(expr, function, arguments_count);
}
}
// f.call(...)
void HOptimizedGraphBuilder::BuildFunctionCall(Call* expr) {
HValue* function = Top(); // f
Handle<Map> function_map = expr->GetReceiverTypes()->first();
HValue* checked_function = AddCheckMap(function, function_map);
// f and call are on the stack in the unoptimized code
// during evaluation of the arguments.
CHECK_ALIVE(VisitExpressions(expr->arguments()));
int args_length = expr->arguments()->length();
int receiver_index = args_length - 1;
// Patch the receiver.
HValue* receiver = BuildWrapReceiver(
environment()->ExpressionStackAt(receiver_index), checked_function);
environment()->SetExpressionStackAt(receiver_index, receiver);
// Call must not be on the stack from now on.
int call_index = args_length + 1;
environment()->RemoveExpressionStackAt(call_index);
HandleIndirectCall(expr, function, args_length);
}
HValue* HOptimizedGraphBuilder::ImplicitReceiverFor(HValue* function,
Handle<JSFunction> target) {
SharedFunctionInfo* shared = target->shared();
if (is_sloppy(shared->language_mode()) && !shared->native()) {
// Cannot embed a direct reference to the global proxy
// as is it dropped on deserialization.
CHECK(!isolate()->serializer_enabled());
Handle<JSObject> global_proxy(target->context()->global_proxy());
return Add<HConstant>(global_proxy);
}
return graph()->GetConstantUndefined();
}
HValue* HOptimizedGraphBuilder::BuildArrayIndexOf(HValue* receiver,
HValue* search_element,
ElementsKind kind,
ArrayIndexOfMode mode) {
DCHECK(IsFastElementsKind(kind));
NoObservableSideEffectsScope no_effects(this);
HValue* elements = AddLoadElements(receiver);
HValue* length = AddLoadArrayLength(receiver, kind);
HValue* initial;
HValue* terminating;
Token::Value token;
LoopBuilder::Direction direction;
if (mode == kFirstIndexOf) {
initial = graph()->GetConstant0();
terminating = length;
token = Token::LT;
direction = LoopBuilder::kPostIncrement;
} else {
DCHECK_EQ(kLastIndexOf, mode);
initial = length;
terminating = graph()->GetConstant0();
token = Token::GT;
direction = LoopBuilder::kPreDecrement;
}
Push(graph()->GetConstantMinus1());
if (IsFastDoubleElementsKind(kind) || IsFastSmiElementsKind(kind)) {
// Make sure that we can actually compare numbers correctly below, see
// https://code.google.com/p/chromium/issues/detail?id=407946 for details.
search_element = AddUncasted<HForceRepresentation>(
search_element, IsFastSmiElementsKind(kind) ? Representation::Smi()
: Representation::Double());
LoopBuilder loop(this, context(), direction);
{
HValue* index = loop.BeginBody(initial, terminating, token);
HValue* element = AddUncasted<HLoadKeyed>(
elements, index, nullptr, nullptr, kind, ALLOW_RETURN_HOLE);
IfBuilder if_issame(this);
if_issame.If<HCompareNumericAndBranch>(element, search_element,
Token::EQ_STRICT);
if_issame.Then();
{
Drop(1);
Push(index);
loop.Break();
}
if_issame.End();
}
loop.EndBody();
} else {
IfBuilder if_isstring(this);
if_isstring.If<HIsStringAndBranch>(search_element);
if_isstring.Then();
{
LoopBuilder loop(this, context(), direction);
{
HValue* index = loop.BeginBody(initial, terminating, token);
HValue* element = AddUncasted<HLoadKeyed>(
elements, index, nullptr, nullptr, kind, ALLOW_RETURN_HOLE);
IfBuilder if_issame(this);
if_issame.If<HIsStringAndBranch>(element);
if_issame.AndIf<HStringCompareAndBranch>(
element, search_element, Token::EQ_STRICT);
if_issame.Then();
{
Drop(1);
Push(index);
loop.Break();
}
if_issame.End();
}
loop.EndBody();
}
if_isstring.Else();
{
IfBuilder if_isnumber(this);
if_isnumber.If<HIsSmiAndBranch>(search_element);
if_isnumber.OrIf<HCompareMap>(
search_element, isolate()->factory()->heap_number_map());
if_isnumber.Then();
{
HValue* search_number =
AddUncasted<HForceRepresentation>(search_element,
Representation::Double());
LoopBuilder loop(this, context(), direction);
{
HValue* index = loop.BeginBody(initial, terminating, token);
HValue* element = AddUncasted<HLoadKeyed>(
elements, index, nullptr, nullptr, kind, ALLOW_RETURN_HOLE);
IfBuilder if_element_isnumber(this);
if_element_isnumber.If<HIsSmiAndBranch>(element);
if_element_isnumber.OrIf<HCompareMap>(
element, isolate()->factory()->heap_number_map());
if_element_isnumber.Then();
{
HValue* number =
AddUncasted<HForceRepresentation>(element,
Representation::Double());
IfBuilder if_issame(this);
if_issame.If<HCompareNumericAndBranch>(
number, search_number, Token::EQ_STRICT);
if_issame.Then();
{
Drop(1);
Push(index);
loop.Break();
}
if_issame.End();
}
if_element_isnumber.End();
}
loop.EndBody();
}
if_isnumber.Else();
{
LoopBuilder loop(this, context(), direction);
{
HValue* index = loop.BeginBody(initial, terminating, token);
HValue* element = AddUncasted<HLoadKeyed>(
elements, index, nullptr, nullptr, kind, ALLOW_RETURN_HOLE);
IfBuilder if_issame(this);
if_issame.If<HCompareObjectEqAndBranch>(
element, search_element);
if_issame.Then();
{
Drop(1);
Push(index);
loop.Break();
}
if_issame.End();
}
loop.EndBody();
}
if_isnumber.End();
}
if_isstring.End();
}
return Pop();
}
template <class T>
bool HOptimizedGraphBuilder::TryHandleArrayCall(T* expr, HValue* function) {
if (!array_function().is_identical_to(expr->target())) {
return false;
}
Handle<AllocationSite> site = expr->allocation_site();
if (site.is_null()) return false;
Add<HCheckValue>(function, array_function());
int arguments_count = expr->arguments()->length();
if (TryInlineArrayCall(expr, arguments_count, site)) return true;
HInstruction* call = PreProcessCall(New<HCallNewArray>(
function, arguments_count + 1, site->GetElementsKind(), site));
if (expr->IsCall()) Drop(1);
ast_context()->ReturnInstruction(call, expr->id());
return true;
}
bool HOptimizedGraphBuilder::CanBeFunctionApplyArguments(Call* expr) {
ZoneList<Expression*>* args = expr->arguments();
if (args->length() != 2) return false;
VariableProxy* arg_two = args->at(1)->AsVariableProxy();
if (arg_two == NULL || !arg_two->var()->IsStackAllocated()) return false;
HValue* arg_two_value = environment()->Lookup(arg_two->var());
if (!arg_two_value->CheckFlag(HValue::kIsArguments)) return false;
DCHECK_NOT_NULL(current_info()->scope()->arguments());
return true;
}
void HOptimizedGraphBuilder::VisitCall(Call* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!is_tracking_positions()) SetSourcePosition(expr->position());
Expression* callee = expr->expression();
int argument_count = expr->arguments()->length() + 1; // Plus receiver.
HInstruction* call = NULL;
TailCallMode syntactic_tail_call_mode = expr->tail_call_mode();
TailCallMode tail_call_mode =
function_state()->ComputeTailCallMode(syntactic_tail_call_mode);
Property* prop = callee->AsProperty();
if (prop != NULL) {
CHECK_ALIVE(VisitForValue(prop->obj()));
HValue* receiver = Top();
SmallMapList* maps;
ComputeReceiverTypes(expr, receiver, &maps, this);
if (prop->key()->IsPropertyName() && maps->length() > 0) {
Handle<String> name = prop->key()->AsLiteral()->AsPropertyName();
PropertyAccessInfo info(this, LOAD, maps->first(), name);
if (!info.CanAccessAsMonomorphic(maps)) {
HandlePolymorphicCallNamed(expr, receiver, maps, name);
return;
}
}
HValue* key = NULL;
if (!prop->key()->IsPropertyName()) {
CHECK_ALIVE(VisitForValue(prop->key()));
key = Pop();
}
CHECK_ALIVE(PushLoad(prop, receiver, key));
HValue* function = Pop();
if (function->IsConstant() &&
HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
// Push the function under the receiver.
environment()->SetExpressionStackAt(0, function);
Push(receiver);
Handle<JSFunction> known_function = Handle<JSFunction>::cast(
HConstant::cast(function)->handle(isolate()));
expr->set_target(known_function);
if (TryIndirectCall(expr)) return;
CHECK_ALIVE(VisitExpressions(expr->arguments()));
Handle<Map> map = maps->length() == 1 ? maps->first() : Handle<Map>();
if (TryInlineBuiltinMethodCall(known_function, map, expr->id(),
expr->arguments()->length())) {
if (FLAG_trace_inlining) {
PrintF("Inlining builtin ");
known_function->ShortPrint();
PrintF("\n");
}
return;
}
if (TryInlineApiMethodCall(expr, receiver, maps)) return;
// Wrap the receiver if necessary.
if (NeedsWrapping(maps->first(), known_function)) {
// Since HWrapReceiver currently cannot actually wrap numbers and
// strings, use the regular call builtin for method calls to wrap
// the receiver.
// TODO(verwaest): Support creation of value wrappers directly in
// HWrapReceiver.
call = NewCallFunction(
function, argument_count, syntactic_tail_call_mode,
ConvertReceiverMode::kNotNullOrUndefined, tail_call_mode);
} else if (TryInlineCall(expr)) {
return;
} else {
call =
NewCallConstantFunction(known_function, argument_count,
syntactic_tail_call_mode, tail_call_mode);
}
} else {
ArgumentsAllowedFlag arguments_flag = ARGUMENTS_NOT_ALLOWED;
if (CanBeFunctionApplyArguments(expr) && expr->is_uninitialized()) {
// We have to use EAGER deoptimization here because Deoptimizer::SOFT
// gets ignored by the always-opt flag, which leads to incorrect code.
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForCallWithArguments,
Deoptimizer::EAGER);
arguments_flag = ARGUMENTS_FAKED;
}
// Push the function under the receiver.
environment()->SetExpressionStackAt(0, function);
Push(receiver);
CHECK_ALIVE(VisitExpressions(expr->arguments(), arguments_flag));
call = NewCallFunction(function, argument_count, syntactic_tail_call_mode,
ConvertReceiverMode::kNotNullOrUndefined,
tail_call_mode);
}
PushArgumentsFromEnvironment(argument_count);
} else {
if (expr->is_possibly_eval()) {
return Bailout(kPossibleDirectCallToEval);
}
// The function is on the stack in the unoptimized code during
// evaluation of the arguments.
CHECK_ALIVE(VisitForValue(expr->expression()));
HValue* function = Top();
if (function->IsConstant() &&
HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
Handle<Object> constant = HConstant::cast(function)->handle(isolate());
Handle<JSFunction> target = Handle<JSFunction>::cast(constant);
expr->SetKnownGlobalTarget(target);
}
// Placeholder for the receiver.
Push(graph()->GetConstantUndefined());
CHECK_ALIVE(VisitExpressions(expr->arguments()));
if (expr->IsMonomorphic() &&
!IsClassConstructor(expr->target()->shared()->kind())) {
Add<HCheckValue>(function, expr->target());
// Patch the global object on the stack by the expected receiver.
HValue* receiver = ImplicitReceiverFor(function, expr->target());
const int receiver_index = argument_count - 1;
environment()->SetExpressionStackAt(receiver_index, receiver);
if (TryInlineBuiltinFunctionCall(expr)) {
if (FLAG_trace_inlining) {
PrintF("Inlining builtin ");
expr->target()->ShortPrint();
PrintF("\n");
}
return;
}
if (TryInlineApiFunctionCall(expr, receiver)) return;
if (TryHandleArrayCall(expr, function)) return;
if (TryInlineCall(expr)) return;
PushArgumentsFromEnvironment(argument_count);
call = NewCallConstantFunction(expr->target(), argument_count,
syntactic_tail_call_mode, tail_call_mode);
} else {
PushArgumentsFromEnvironment(argument_count);
if (expr->is_uninitialized()) {
// We've never seen this call before, so let's have Crankshaft learn
// through the type vector.
call = NewCallFunctionViaIC(function, argument_count,
syntactic_tail_call_mode,
ConvertReceiverMode::kNullOrUndefined,
tail_call_mode, expr->CallFeedbackICSlot());
} else {
call = NewCallFunction(
function, argument_count, syntactic_tail_call_mode,
ConvertReceiverMode::kNullOrUndefined, tail_call_mode);
}
}
}
Drop(1); // Drop the function.
return ast_context()->ReturnInstruction(call, expr->id());
}
bool HOptimizedGraphBuilder::TryInlineArrayCall(Expression* expression,
int argument_count,
Handle<AllocationSite> site) {
Handle<JSFunction> caller = current_info()->closure();
Handle<JSFunction> target = array_function();
if (!site->CanInlineCall()) {
TraceInline(target, caller, "AllocationSite requested no inlining.");
return false;
}
if (argument_count > 1) {
TraceInline(target, caller, "Too many arguments to inline.");
return false;
}
int array_length = 0;
// Do not inline if the constant length argument is not a smi or outside the
// valid range for unrolled loop initialization.
if (argument_count == 1) {
HValue* argument = Top();
if (!argument->IsConstant()) {
TraceInline(target, caller,
"Dont inline [new] Array(n) where n isn't constant.");
return false;
}
HConstant* constant_argument = HConstant::cast(argument);
if (!constant_argument->HasSmiValue()) {
TraceInline(target, caller,
"Constant length outside of valid inlining range.");
return false;
}
array_length = constant_argument->Integer32Value();
if (array_length < 0 || array_length > kElementLoopUnrollThreshold) {
TraceInline(target, caller,
"Constant length outside of valid inlining range.");
return false;
}
}
TraceInline(target, caller, NULL);
NoObservableSideEffectsScope no_effects(this);
// Register on the site for deoptimization if the transition feedback changes.
top_info()->dependencies()->AssumeTransitionStable(site);
// Build the array.
ElementsKind kind = site->GetElementsKind();
HValue* capacity;
HValue* length;
if (array_length == 0) {
STATIC_ASSERT(0 < JSArray::kPreallocatedArrayElements);
const int initial_capacity = JSArray::kPreallocatedArrayElements;
capacity = Add<HConstant>(initial_capacity);
length = graph()->GetConstant0();
} else {
length = Top();
capacity = length;
kind = GetHoleyElementsKind(kind);
}
// These HForceRepresentations are because we store these as fields in the
// objects we construct, and an int32-to-smi HChange could deopt. Accept
// the deopt possibility now, before allocation occurs.
length = AddUncasted<HForceRepresentation>(length, Representation::Smi());
capacity = AddUncasted<HForceRepresentation>(capacity, Representation::Smi());
// Generate size calculation code here in order to make it dominate
// the JSArray allocation.
HValue* elements_size = BuildCalculateElementsSize(kind, capacity);
// Bail out for large objects.
HValue* max_size = Add<HConstant>(kMaxRegularHeapObjectSize);
Add<HBoundsCheck>(elements_size, max_size);
// Allocate (dealing with failure appropriately).
AllocationSiteMode mode = DONT_TRACK_ALLOCATION_SITE;
HAllocate* new_object = AllocateJSArrayObject(mode);
// Fill in the fields: map, properties, length.
Handle<Map> map_constant(isolate()->get_initial_js_array_map(kind));
HValue* map = Add<HConstant>(map_constant);
BuildJSArrayHeader(new_object, map,
nullptr, // set elements to empty fixed array
mode, kind, nullptr, length);
// Allocate and initialize the elements.
HAllocate* elements = BuildAllocateElements(kind, elements_size);
BuildInitializeElementsHeader(elements, kind, capacity);
BuildFillElementsWithHole(elements, kind, graph()->GetConstant0(), capacity);
// Set the elements.
Add<HStoreNamedField>(new_object, HObjectAccess::ForElementsPointer(),
elements);
int args_to_drop = argument_count + (expression->IsCall() ? 2 : 1);
Drop(args_to_drop);
ast_context()->ReturnValue(new_object);
return true;
}
// Checks whether allocation using the given constructor can be inlined.
static bool IsAllocationInlineable(Handle<JSFunction> constructor) {
return constructor->has_initial_map() &&
!IsDerivedConstructor(constructor->shared()->kind()) &&
!constructor->initial_map()->is_dictionary_map() &&
constructor->initial_map()->instance_type() == JS_OBJECT_TYPE &&
constructor->initial_map()->instance_size() <
HAllocate::kMaxInlineSize;
}
void HOptimizedGraphBuilder::VisitCallNew(CallNew* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!is_tracking_positions()) SetSourcePosition(expr->position());
int argument_count = expr->arguments()->length() + 1; // Plus constructor.
Factory* factory = isolate()->factory();
// The constructor function is on the stack in the unoptimized code
// during evaluation of the arguments.
CHECK_ALIVE(VisitForValue(expr->expression()));
HValue* function = Top();
CHECK_ALIVE(VisitExpressions(expr->arguments()));
if (function->IsConstant() &&
HConstant::cast(function)->handle(isolate())->IsJSFunction()) {
Handle<Object> constant = HConstant::cast(function)->handle(isolate());
expr->SetKnownGlobalTarget(Handle<JSFunction>::cast(constant));
}
if (FLAG_inline_construct &&
expr->IsMonomorphic() &&
IsAllocationInlineable(expr->target())) {
Handle<JSFunction> constructor = expr->target();
DCHECK(constructor->shared()->construct_stub() ==
isolate()->builtins()->builtin(
Builtins::kJSConstructStubGenericRestrictedReturn) ||
constructor->shared()->construct_stub() ==
isolate()->builtins()->builtin(
Builtins::kJSConstructStubGenericUnrestrictedReturn) ||
constructor->shared()->construct_stub() ==
isolate()->builtins()->builtin(Builtins::kJSConstructStubApi));
HValue* check = Add<HCheckValue>(function, constructor);
// Force completion of inobject slack tracking before generating
// allocation code to finalize instance size.
constructor->CompleteInobjectSlackTrackingIfActive();
// Calculate instance size from initial map of constructor.
DCHECK(constructor->has_initial_map());
Handle<Map> initial_map(constructor->initial_map());
int instance_size = initial_map->instance_size();
// Allocate an instance of the implicit receiver object.
HValue* size_in_bytes = Add<HConstant>(instance_size);
HAllocationMode allocation_mode;
HAllocate* receiver = BuildAllocate(
size_in_bytes, HType::JSObject(), JS_OBJECT_TYPE, allocation_mode);
receiver->set_known_initial_map(initial_map);
// Initialize map and fields of the newly allocated object.
{ NoObservableSideEffectsScope no_effects(this);
DCHECK(initial_map->instance_type() == JS_OBJECT_TYPE);
Add<HStoreNamedField>(receiver,
HObjectAccess::ForMapAndOffset(initial_map, JSObject::kMapOffset),
Add<HConstant>(initial_map));
HValue* empty_fixed_array = Add<HConstant>(factory->empty_fixed_array());
Add<HStoreNamedField>(receiver,
HObjectAccess::ForMapAndOffset(initial_map,
JSObject::kPropertiesOffset),
empty_fixed_array);
Add<HStoreNamedField>(receiver,
HObjectAccess::ForMapAndOffset(initial_map,
JSObject::kElementsOffset),
empty_fixed_array);
BuildInitializeInobjectProperties(receiver, initial_map);
}
// Replace the constructor function with a newly allocated receiver using
// the index of the receiver from the top of the expression stack.
const int receiver_index = argument_count - 1;
DCHECK(environment()->ExpressionStackAt(receiver_index) == function);
environment()->SetExpressionStackAt(receiver_index, receiver);
if (TryInlineConstruct(expr, receiver)) {
// Inlining worked, add a dependency on the initial map to make sure that
// this code is deoptimized whenever the initial map of the constructor
// changes.
top_info()->dependencies()->AssumeInitialMapCantChange(initial_map);
return;
}
// TODO(mstarzinger): For now we remove the previous HAllocate and all
// corresponding instructions and instead add HPushArguments for the
// arguments in case inlining failed. What we actually should do is for
// inlining to try to build a subgraph without mutating the parent graph.
HInstruction* instr = current_block()->last();
do {
HInstruction* prev_instr = instr->previous();
instr->DeleteAndReplaceWith(NULL);
instr = prev_instr;
} while (instr != check);
environment()->SetExpressionStackAt(receiver_index, function);
} else {
// The constructor function is both an operand to the instruction and an
// argument to the construct call.
if (TryHandleArrayCall(expr, function)) return;
}
HValue* arity = Add<HConstant>(argument_count - 1);
HValue* op_vals[] = {function, function, arity};
Callable callable = CodeFactory::Construct(isolate());
HConstant* stub = Add<HConstant>(callable.code());
PushArgumentsFromEnvironment(argument_count);
HInstruction* construct = New<HCallWithDescriptor>(
stub, argument_count, callable.descriptor(), ArrayVector(op_vals));
return ast_context()->ReturnInstruction(construct, expr->id());
}
void HOptimizedGraphBuilder::BuildInitializeInobjectProperties(
HValue* receiver, Handle<Map> initial_map) {
if (initial_map->GetInObjectProperties() != 0) {
HConstant* undefined = graph()->GetConstantUndefined();
for (int i = 0; i < initial_map->GetInObjectProperties(); i++) {
int property_offset = initial_map->GetInObjectPropertyOffset(i);
Add<HStoreNamedField>(receiver, HObjectAccess::ForMapAndOffset(
initial_map, property_offset),
undefined);
}
}
}
void HOptimizedGraphBuilder::GenerateMaxSmi(CallRuntime* expr) {
DCHECK(expr->arguments()->length() == 0);
HConstant* max_smi = New<HConstant>(static_cast<int32_t>(Smi::kMaxValue));
return ast_context()->ReturnInstruction(max_smi, expr->id());
}
void HOptimizedGraphBuilder::GenerateTypedArrayMaxSizeInHeap(
CallRuntime* expr) {
DCHECK(expr->arguments()->length() == 0);
HConstant* result = New<HConstant>(static_cast<int32_t>(
FLAG_typed_array_max_size_in_heap));
return ast_context()->ReturnInstruction(result, expr->id());
}
void HOptimizedGraphBuilder::GenerateArrayBufferGetByteLength(
CallRuntime* expr) {
DCHECK(expr->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(expr->arguments()->at(0)));
HValue* buffer = Pop();
HInstruction* result = New<HLoadNamedField>(
buffer, nullptr, HObjectAccess::ForJSArrayBufferByteLength());
return ast_context()->ReturnInstruction(result, expr->id());
}
void HOptimizedGraphBuilder::GenerateArrayBufferViewGetByteLength(
CallRuntime* expr) {
NoObservableSideEffectsScope scope(this);
DCHECK(expr->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(expr->arguments()->at(0)));
HValue* view = Pop();
return ast_context()->ReturnValue(BuildArrayBufferViewFieldAccessor(
view, nullptr,
FieldIndex::ForInObjectOffset(JSArrayBufferView::kByteLengthOffset)));
}
void HOptimizedGraphBuilder::GenerateArrayBufferViewGetByteOffset(
CallRuntime* expr) {
NoObservableSideEffectsScope scope(this);
DCHECK(expr->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(expr->arguments()->at(0)));
HValue* view = Pop();
return ast_context()->ReturnValue(BuildArrayBufferViewFieldAccessor(
view, nullptr,
FieldIndex::ForInObjectOffset(JSArrayBufferView::kByteOffsetOffset)));
}
void HOptimizedGraphBuilder::GenerateArrayBufferViewWasNeutered(
CallRuntime* expr) {
NoObservableSideEffectsScope scope(this);
DCHECK_EQ(expr->arguments()->length(), 1);
CHECK_ALIVE(VisitForValue(expr->arguments()->at(0)));
HValue* view = Pop();
HInstruction* buffer = Add<HLoadNamedField>(
view, nullptr, HObjectAccess::ForJSArrayBufferViewBuffer());
HInstruction* flags = Add<HLoadNamedField>(
buffer, nullptr, HObjectAccess::ForJSArrayBufferBitField());
HValue* was_neutered_mask =
Add<HConstant>(1 << JSArrayBuffer::WasNeutered::kShift);
HValue* was_neutered =
AddUncasted<HBitwise>(Token::BIT_AND, flags, was_neutered_mask);
return ast_context()->ReturnValue(was_neutered);
}
void HOptimizedGraphBuilder::GenerateTypedArrayGetLength(
CallRuntime* expr) {
NoObservableSideEffectsScope scope(this);
DCHECK(expr->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(expr->arguments()->at(0)));
HValue* view = Pop();
return ast_context()->ReturnValue(BuildArrayBufferViewFieldAccessor(
view, nullptr,
FieldIndex::ForInObjectOffset(JSTypedArray::kLengthOffset)));
}
void HOptimizedGraphBuilder::VisitCallRuntime(CallRuntime* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (expr->is_jsruntime()) {
// Crankshaft always specializes to the native context, so we can just grab
// the constant function from the current native context and embed that into
// the code object.
Handle<JSFunction> known_function(
JSFunction::cast(
current_info()->native_context()->get(expr->context_index())),
isolate());
// The callee and the receiver both have to be pushed onto the operand stack
// before arguments are being evaluated.
HConstant* function = Add<HConstant>(known_function);
HValue* receiver = ImplicitReceiverFor(function, known_function);
Push(function);
Push(receiver);
int argument_count = expr->arguments()->length() + 1; // Count receiver.
CHECK_ALIVE(VisitExpressions(expr->arguments()));
PushArgumentsFromEnvironment(argument_count);
HInstruction* call = NewCallConstantFunction(known_function, argument_count,
TailCallMode::kDisallow,
TailCallMode::kDisallow);
Drop(1); // Function
return ast_context()->ReturnInstruction(call, expr->id());
}
const Runtime::Function* function = expr->function();
DCHECK(function != NULL);
switch (function->function_id) {
#define CALL_INTRINSIC_GENERATOR(Name) \
case Runtime::kInline##Name: \
return Generate##Name(expr);
FOR_EACH_HYDROGEN_INTRINSIC(CALL_INTRINSIC_GENERATOR)
#undef CALL_INTRINSIC_GENERATOR
default: {
int argument_count = expr->arguments()->length();
CHECK_ALIVE(VisitExpressions(expr->arguments()));
PushArgumentsFromEnvironment(argument_count);
HCallRuntime* call = New<HCallRuntime>(function, argument_count);
return ast_context()->ReturnInstruction(call, expr->id());
}
}
}
void HOptimizedGraphBuilder::VisitUnaryOperation(UnaryOperation* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
switch (expr->op()) {
case Token::DELETE: return VisitDelete(expr);
case Token::VOID: return VisitVoid(expr);
case Token::TYPEOF: return VisitTypeof(expr);
case Token::NOT: return VisitNot(expr);
default: UNREACHABLE();
}
}
void HOptimizedGraphBuilder::VisitDelete(UnaryOperation* expr) {
Property* prop = expr->expression()->AsProperty();
VariableProxy* proxy = expr->expression()->AsVariableProxy();
if (prop != NULL) {
CHECK_ALIVE(VisitForValue(prop->obj()));
CHECK_ALIVE(VisitForValue(prop->key()));
HValue* key = Pop();
HValue* obj = Pop();
HValue* language_mode = Add<HConstant>(
static_cast<int32_t>(function_language_mode()), Representation::Smi());
Add<HPushArguments>(obj, key, language_mode);
HInstruction* instr =
New<HCallRuntime>(Runtime::FunctionForId(Runtime::kDeleteProperty), 3);
return ast_context()->ReturnInstruction(instr, expr->id());
} else if (proxy != NULL) {
Variable* var = proxy->var();
if (var->IsUnallocated()) {
Bailout(kDeleteWithGlobalVariable);
} else if (var->IsStackAllocated() || var->IsContextSlot()) {
// Result of deleting non-global variables is false. 'this' is not really
// a variable, though we implement it as one. The subexpression does not
// have side effects.
HValue* value = var->is_this() ? graph()->GetConstantTrue()
: graph()->GetConstantFalse();
return ast_context()->ReturnValue(value);
} else {
Bailout(kDeleteWithNonGlobalVariable);
}
} else {
// Result of deleting non-property, non-variable reference is true.
// Evaluate the subexpression for side effects.
CHECK_ALIVE(VisitForEffect(expr->expression()));
return ast_context()->ReturnValue(graph()->GetConstantTrue());
}
}
void HOptimizedGraphBuilder::VisitVoid(UnaryOperation* expr) {
CHECK_ALIVE(VisitForEffect(expr->expression()));
return ast_context()->ReturnValue(graph()->GetConstantUndefined());
}
void HOptimizedGraphBuilder::VisitTypeof(UnaryOperation* expr) {
CHECK_ALIVE(VisitForTypeOf(expr->expression()));
HValue* value = Pop();
HInstruction* instr = New<HTypeof>(value);
return ast_context()->ReturnInstruction(instr, expr->id());
}
void HOptimizedGraphBuilder::VisitNot(UnaryOperation* expr) {
if (ast_context()->IsTest()) {
TestContext* context = TestContext::cast(ast_context());
VisitForControl(expr->expression(),
context->if_false(),
context->if_true());
return;
}
if (ast_context()->IsEffect()) {
VisitForEffect(expr->expression());
return;
}
DCHECK(ast_context()->IsValue());
HBasicBlock* materialize_false = graph()->CreateBasicBlock();
HBasicBlock* materialize_true = graph()->CreateBasicBlock();
CHECK_BAILOUT(VisitForControl(expr->expression(),
materialize_false,
materialize_true));
if (materialize_false->HasPredecessor()) {
materialize_false->SetJoinId(expr->MaterializeFalseId());
set_current_block(materialize_false);
Push(graph()->GetConstantFalse());
} else {
materialize_false = NULL;
}
if (materialize_true->HasPredecessor()) {
materialize_true->SetJoinId(expr->MaterializeTrueId());
set_current_block(materialize_true);
Push(graph()->GetConstantTrue());
} else {
materialize_true = NULL;
}
HBasicBlock* join =
CreateJoin(materialize_false, materialize_true, expr->id());
set_current_block(join);
if (join != NULL) return ast_context()->ReturnValue(Pop());
}
static Representation RepresentationFor(AstType* type) {
DisallowHeapAllocation no_allocation;
if (type->Is(AstType::None())) return Representation::None();
if (type->Is(AstType::SignedSmall())) return Representation::Smi();
if (type->Is(AstType::Signed32())) return Representation::Integer32();
if (type->Is(AstType::Number())) return Representation::Double();
return Representation::Tagged();
}
HInstruction* HOptimizedGraphBuilder::BuildIncrement(CountOperation* expr) {
// The input to the count operation is on top of the expression stack.
Representation rep = RepresentationFor(expr->type());
if (rep.IsNone() || rep.IsTagged()) {
rep = Representation::Smi();
}
// We need an explicit HValue representing ToNumber(input). The
// actual HChange instruction we need is (sometimes) added in a later
// phase, so it is not available now to be used as an input to HAdd and
// as the return value.
HInstruction* number_input = AddUncasted<HForceRepresentation>(Pop(), rep);
if (!rep.IsDouble()) {
number_input->SetFlag(HInstruction::kFlexibleRepresentation);
number_input->SetFlag(HInstruction::kCannotBeTagged);
}
Push(number_input);
// The addition has no side effects, so we do not need
// to simulate the expression stack after this instruction.
// Any later failures deopt to the load of the input or earlier.
HConstant* delta = (expr->op() == Token::INC)
? graph()->GetConstant1()
: graph()->GetConstantMinus1();
HInstruction* instr = AddUncasted<HAdd>(Top(), delta);
if (instr->IsAdd()) {
HAdd* add = HAdd::cast(instr);
add->set_observed_input_representation(1, rep);
add->set_observed_input_representation(2, Representation::Smi());
}
instr->ClearAllSideEffects();
instr->SetFlag(HInstruction::kCannotBeTagged);
return instr;
}
void HOptimizedGraphBuilder::BuildStoreForEffect(
Expression* expr, Property* prop, FeedbackSlot slot, BailoutId ast_id,
BailoutId return_id, HValue* object, HValue* key, HValue* value) {
EffectContext for_effect(this);
Push(object);
if (key != NULL) Push(key);
Push(value);
BuildStore(expr, prop, slot, ast_id, return_id);
}
void HOptimizedGraphBuilder::VisitCountOperation(CountOperation* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!is_tracking_positions()) SetSourcePosition(expr->position());
Expression* target = expr->expression();
VariableProxy* proxy = target->AsVariableProxy();
Property* prop = target->AsProperty();
if (proxy == NULL && prop == NULL) {
return Bailout(kInvalidLhsInCountOperation);
}
// Match the full code generator stack by simulating an extra stack
// element for postfix operations in a non-effect context. The return
// value is ToNumber(input).
bool returns_original_input =
expr->is_postfix() && !ast_context()->IsEffect();
HValue* input = NULL; // ToNumber(original_input).
HValue* after = NULL; // The result after incrementing or decrementing.
if (proxy != NULL) {
Variable* var = proxy->var();
if (var->mode() == CONST) {
return Bailout(kNonInitializerAssignmentToConst);
}
// Argument of the count operation is a variable, not a property.
DCHECK(prop == NULL);
CHECK_ALIVE(VisitForValue(target));
after = BuildIncrement(expr);
input = returns_original_input ? Top() : Pop();
Push(after);
switch (var->location()) {
case VariableLocation::UNALLOCATED:
HandleGlobalVariableAssignment(var, after, expr->CountSlot(),
expr->AssignmentId());
break;
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL:
BindIfLive(var, after);
break;
case VariableLocation::CONTEXT: {
HValue* context = BuildContextChainWalk(var);
HStoreContextSlot::Mode mode = IsLexicalVariableMode(var->mode())
? HStoreContextSlot::kCheckDeoptimize : HStoreContextSlot::kNoCheck;
HStoreContextSlot* instr = Add<HStoreContextSlot>(context, var->index(),
mode, after);
if (instr->HasObservableSideEffects()) {
Add<HSimulate>(expr->AssignmentId(), REMOVABLE_SIMULATE);
}
break;
}
case VariableLocation::LOOKUP:
return Bailout(kLookupVariableInCountOperation);
case VariableLocation::MODULE:
UNREACHABLE();
}
Drop(returns_original_input ? 2 : 1);
return ast_context()->ReturnValue(expr->is_postfix() ? input : after);
}
// Argument of the count operation is a property.
DCHECK(prop != NULL);
if (returns_original_input) Push(graph()->GetConstantUndefined());
CHECK_ALIVE(VisitForValue(prop->obj()));
HValue* object = Top();
HValue* key = NULL;
if (!prop->key()->IsPropertyName() || prop->IsStringAccess()) {
CHECK_ALIVE(VisitForValue(prop->key()));
key = Top();
}
CHECK_ALIVE(PushLoad(prop, object, key));
after = BuildIncrement(expr);
if (returns_original_input) {
input = Pop();
// Drop object and key to push it again in the effect context below.
Drop(key == NULL ? 1 : 2);
environment()->SetExpressionStackAt(0, input);
CHECK_ALIVE(BuildStoreForEffect(expr, prop, expr->CountSlot(), expr->id(),
expr->AssignmentId(), object, key, after));
return ast_context()->ReturnValue(Pop());
}
environment()->SetExpressionStackAt(0, after);
return BuildStore(expr, prop, expr->CountSlot(), expr->id(),
expr->AssignmentId());
}
HInstruction* HOptimizedGraphBuilder::BuildStringCharCodeAt(
HValue* string,
HValue* index) {
if (string->IsConstant() && index->IsConstant()) {
HConstant* c_string = HConstant::cast(string);
HConstant* c_index = HConstant::cast(index);
if (c_string->HasStringValue() && c_index->HasNumberValue()) {
int32_t i = c_index->NumberValueAsInteger32();
Handle<String> s = c_string->StringValue();
if (i < 0 || i >= s->length()) {
return New<HConstant>(std::numeric_limits<double>::quiet_NaN());
}
return New<HConstant>(s->Get(i));
}
}
string = BuildCheckString(string);
index = Add<HBoundsCheck>(index, AddLoadStringLength(string));
return New<HStringCharCodeAt>(string, index);
}
// Checks if the given shift amounts have following forms:
// (N1) and (N2) with N1 + N2 = 32; (sa) and (32 - sa).
static bool ShiftAmountsAllowReplaceByRotate(HValue* sa,
HValue* const32_minus_sa) {
if (sa->IsConstant() && const32_minus_sa->IsConstant()) {
const HConstant* c1 = HConstant::cast(sa);
const HConstant* c2 = HConstant::cast(const32_minus_sa);
return c1->HasInteger32Value() && c2->HasInteger32Value() &&
(c1->Integer32Value() + c2->Integer32Value() == 32);
}
if (!const32_minus_sa->IsSub()) return false;
HSub* sub = HSub::cast(const32_minus_sa);
return sub->left()->EqualsInteger32Constant(32) && sub->right() == sa;
}
// Checks if the left and the right are shift instructions with the oposite
// directions that can be replaced by one rotate right instruction or not.
// Returns the operand and the shift amount for the rotate instruction in the
// former case.
bool HGraphBuilder::MatchRotateRight(HValue* left,
HValue* right,
HValue** operand,
HValue** shift_amount) {
HShl* shl;
HShr* shr;
if (left->IsShl() && right->IsShr()) {
shl = HShl::cast(left);
shr = HShr::cast(right);
} else if (left->IsShr() && right->IsShl()) {
shl = HShl::cast(right);
shr = HShr::cast(left);
} else {
return false;
}
if (shl->left() != shr->left()) return false;
if (!ShiftAmountsAllowReplaceByRotate(shl->right(), shr->right()) &&
!ShiftAmountsAllowReplaceByRotate(shr->right(), shl->right())) {
return false;
}
*operand = shr->left();
*shift_amount = shr->right();
return true;
}
bool CanBeZero(HValue* right) {
if (right->IsConstant()) {
HConstant* right_const = HConstant::cast(right);
if (right_const->HasInteger32Value() &&
(right_const->Integer32Value() & 0x1f) != 0) {
return false;
}
}
return true;
}
HValue* HGraphBuilder::EnforceNumberType(HValue* number, AstType* expected) {
if (expected->Is(AstType::SignedSmall())) {
return AddUncasted<HForceRepresentation>(number, Representation::Smi());
}
if (expected->Is(AstType::Signed32())) {
return AddUncasted<HForceRepresentation>(number,
Representation::Integer32());
}
return number;
}
HValue* HGraphBuilder::TruncateToNumber(HValue* value, AstType** expected) {
if (value->IsConstant()) {
HConstant* constant = HConstant::cast(value);
Maybe<HConstant*> number =
constant->CopyToTruncatedNumber(isolate(), zone());
if (number.IsJust()) {
*expected = AstType::Number();
return AddInstruction(number.FromJust());
}
}
// We put temporary values on the stack, which don't correspond to anything
// in baseline code. Since nothing is observable we avoid recording those
// pushes with a NoObservableSideEffectsScope.
NoObservableSideEffectsScope no_effects(this);
AstType* expected_type = *expected;
// Separate the number type from the rest.
AstType* expected_obj =
AstType::Intersect(expected_type, AstType::NonNumber(), zone());
AstType* expected_number =
AstType::Intersect(expected_type, AstType::Number(), zone());
// We expect to get a number.
// (We need to check first, since AstType::None->Is(AstType::Any()) == true.
if (expected_obj->Is(AstType::None())) {
DCHECK(!expected_number->Is(AstType::None()));
return value;
}
if (expected_obj->Is(AstType::Undefined())) {
// This is already done by HChange.
*expected = AstType::Union(expected_number, AstType::Number(), zone());
return value;
}
return value;
}
HValue* HOptimizedGraphBuilder::BuildBinaryOperation(
BinaryOperation* expr,
HValue* left,
HValue* right,
PushBeforeSimulateBehavior push_sim_result) {
AstType* left_type = bounds_.get(expr->left()).lower;
AstType* right_type = bounds_.get(expr->right()).lower;
AstType* result_type = bounds_.get(expr).lower;
Maybe<int> fixed_right_arg = expr->fixed_right_arg();
Handle<AllocationSite> allocation_site = expr->allocation_site();
HAllocationMode allocation_mode;
if (FLAG_allocation_site_pretenuring && !allocation_site.is_null()) {
allocation_mode = HAllocationMode(allocation_site);
}
HValue* result = HGraphBuilder::BuildBinaryOperation(
expr->op(), left, right, left_type, right_type, result_type,
fixed_right_arg, allocation_mode, expr->id());
// Add a simulate after instructions with observable side effects, and
// after phis, which are the result of BuildBinaryOperation when we
// inlined some complex subgraph.
if (result->HasObservableSideEffects() || result->IsPhi()) {
if (push_sim_result == PUSH_BEFORE_SIMULATE) {
Push(result);
Add<HSimulate>(expr->id(), REMOVABLE_SIMULATE);
Drop(1);
} else {
Add<HSimulate>(expr->id(), REMOVABLE_SIMULATE);
}
}
return result;
}
HValue* HGraphBuilder::BuildBinaryOperation(
Token::Value op, HValue* left, HValue* right, AstType* left_type,
AstType* right_type, AstType* result_type, Maybe<int> fixed_right_arg,
HAllocationMode allocation_mode, BailoutId opt_id) {
bool maybe_string_add = false;
if (op == Token::ADD) {
// If we are adding constant string with something for which we don't have
// a feedback yet, assume that it's also going to be a string and don't
// generate deopt instructions.
if (!left_type->IsInhabited() && right->IsConstant() &&
HConstant::cast(right)->HasStringValue()) {
left_type = AstType::String();
}
if (!right_type->IsInhabited() && left->IsConstant() &&
HConstant::cast(left)->HasStringValue()) {
right_type = AstType::String();
}
maybe_string_add = (left_type->Maybe(AstType::String()) ||
left_type->Maybe(AstType::Receiver()) ||
right_type->Maybe(AstType::String()) ||
right_type->Maybe(AstType::Receiver()));
}
Representation left_rep = RepresentationFor(left_type);
Representation right_rep = RepresentationFor(right_type);
if (!left_type->IsInhabited()) {
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForLHSOfBinaryOperation,
Deoptimizer::SOFT);
left_type = AstType::Any();
left_rep = RepresentationFor(left_type);
maybe_string_add = op == Token::ADD;
}
if (!right_type->IsInhabited()) {
Add<HDeoptimize>(
DeoptimizeReason::kInsufficientTypeFeedbackForRHSOfBinaryOperation,
Deoptimizer::SOFT);
right_type = AstType::Any();
right_rep = RepresentationFor(right_type);
maybe_string_add = op == Token::ADD;
}
if (!maybe_string_add) {
left = TruncateToNumber(left, &left_type);
right = TruncateToNumber(right, &right_type);
}
// Special case for string addition here.
if (op == Token::ADD &&
(left_type->Is(AstType::String()) || right_type->Is(AstType::String()))) {
// Validate type feedback for left argument.
if (left_type->Is(AstType::String())) {
left = BuildCheckString(left);
}
// Validate type feedback for right argument.
if (right_type->Is(AstType::String())) {
right = BuildCheckString(right);
}
// Convert left argument as necessary.
if (left_type->Is(AstType::Number())) {
DCHECK(right_type->Is(AstType::String()));
left = BuildNumberToString(left, left_type);
} else if (!left_type->Is(AstType::String())) {
DCHECK(right_type->Is(AstType::String()));
return AddUncasted<HStringAdd>(
left, right, allocation_mode.GetPretenureMode(),
STRING_ADD_CONVERT_LEFT, allocation_mode.feedback_site());
}
// Convert right argument as necessary.
if (right_type->Is(AstType::Number())) {
DCHECK(left_type->Is(AstType::String()));
right = BuildNumberToString(right, right_type);
} else if (!right_type->Is(AstType::String())) {
DCHECK(left_type->Is(AstType::String()));
return AddUncasted<HStringAdd>(
left, right, allocation_mode.GetPretenureMode(),
STRING_ADD_CONVERT_RIGHT, allocation_mode.feedback_site());
}
// Fast paths for empty constant strings.
Handle<String> left_string =
left->IsConstant() && HConstant::cast(left)->HasStringValue()
? HConstant::cast(left)->StringValue()
: Handle<String>();
Handle<String> right_string =
right->IsConstant() && HConstant::cast(right)->HasStringValue()
? HConstant::cast(right)->StringValue()
: Handle<String>();
if (!left_string.is_null() && left_string->length() == 0) return right;
if (!right_string.is_null() && right_string->length() == 0) return left;
if (!left_string.is_null() && !right_string.is_null()) {
return AddUncasted<HStringAdd>(
left, right, allocation_mode.GetPretenureMode(),
STRING_ADD_CHECK_NONE, allocation_mode.feedback_site());
}
// Register the dependent code with the allocation site.
if (!allocation_mode.feedback_site().is_null()) {
DCHECK(!graph()->info()->IsStub());
Handle<AllocationSite> site(allocation_mode.feedback_site());
top_info()->dependencies()->AssumeTenuringDecision(site);
}
// Inline the string addition into the stub when creating allocation
// mementos to gather allocation site feedback, or if we can statically
// infer that we're going to create a cons string.
if ((graph()->info()->IsStub() &&
allocation_mode.CreateAllocationMementos()) ||
(left->IsConstant() &&
HConstant::cast(left)->HasStringValue() &&
HConstant::cast(left)->StringValue()->length() + 1 >=
ConsString::kMinLength) ||
(right->IsConstant() &&
HConstant::cast(right)->HasStringValue() &&
HConstant::cast(right)->StringValue()->length() + 1 >=
ConsString::kMinLength)) {
return BuildStringAdd(left, right, allocation_mode);
}
// Fallback to using the string add stub.
return AddUncasted<HStringAdd>(
left, right, allocation_mode.GetPretenureMode(), STRING_ADD_CHECK_NONE,
allocation_mode.feedback_site());
}
// Special case for +x here.
if (op == Token::MUL) {
if (left->EqualsInteger32Constant(1)) {
return BuildToNumber(right);
}
if (right->EqualsInteger32Constant(1)) {
return BuildToNumber(left);
}
}
if (graph()->info()->IsStub()) {
left = EnforceNumberType(left, left_type);
right = EnforceNumberType(right, right_type);
}
Representation result_rep = RepresentationFor(result_type);
bool is_non_primitive = (left_rep.IsTagged() && !left_rep.IsSmi()) ||
(right_rep.IsTagged() && !right_rep.IsSmi());
HInstruction* instr = NULL;
// Only the stub is allowed to call into the runtime, since otherwise we would
// inline several instructions (including the two pushes) for every tagged
// operation in optimized code, which is more expensive, than a stub call.
if (graph()->info()->IsStub() && is_non_primitive) {
HValue* values[] = {left, right};
#define GET_STUB(Name) \
do { \
Callable callable = CodeFactory::Name(isolate()); \
HValue* stub = Add<HConstant>(callable.code()); \
instr = AddUncasted<HCallWithDescriptor>(stub, 0, callable.descriptor(), \
ArrayVector(values)); \
} while (false)
switch (op) {
default:
UNREACHABLE();
case Token::ADD:
GET_STUB(Add);
break;
case Token::SUB:
GET_STUB(Subtract);
break;
case Token::MUL:
GET_STUB(Multiply);
break;
case Token::DIV:
GET_STUB(Divide);
break;
case Token::MOD:
GET_STUB(Modulus);
break;
case Token::BIT_OR:
GET_STUB(BitwiseOr);
break;
case Token::BIT_AND:
GET_STUB(BitwiseAnd);
break;
case Token::BIT_XOR:
GET_STUB(BitwiseXor);
break;
case Token::SAR:
GET_STUB(ShiftRight);
break;
case Token::SHR:
GET_STUB(ShiftRightLogical);
break;
case Token::SHL:
GET_STUB(ShiftLeft);
break;
}
#undef GET_STUB
} else {
switch (op) {
case Token::ADD:
instr = AddUncasted<HAdd>(left, right);
break;
case Token::SUB:
instr = AddUncasted<HSub>(left, right);
break;
case Token::MUL:
instr = AddUncasted<HMul>(left, right);
break;
case Token::MOD: {
if (fixed_right_arg.IsJust() &&
!right->EqualsInteger32Constant(fixed_right_arg.FromJust())) {
HConstant* fixed_right =
Add<HConstant>(static_cast<int>(fixed_right_arg.FromJust()));
IfBuilder if_same(this);
if_same.If<HCompareNumericAndBranch>(right, fixed_right, Token::EQ);
if_same.Then();
if_same.ElseDeopt(DeoptimizeReason::kUnexpectedRHSOfBinaryOperation);
right = fixed_right;
}
instr = AddUncasted<HMod>(left, right);
break;
}
case Token::DIV:
instr = AddUncasted<HDiv>(left, right);
break;
case Token::BIT_XOR:
case Token::BIT_AND:
instr = AddUncasted<HBitwise>(op, left, right);
break;
case Token::BIT_OR: {
HValue *operand, *shift_amount;
if (left_type->Is(AstType::Signed32()) &&
right_type->Is(AstType::Signed32()) &&
MatchRotateRight(left, right, &operand, &shift_amount)) {
instr = AddUncasted<HRor>(operand, shift_amount);
} else {
instr = AddUncasted<HBitwise>(op, left, right);
}
break;
}
case Token::SAR:
instr = AddUncasted<HSar>(left, right);
break;
case Token::SHR:
instr = AddUncasted<HShr>(left, right);
if (instr->IsShr() && CanBeZero(right)) {
graph()->RecordUint32Instruction(instr);
}
break;
case Token::SHL:
instr = AddUncasted<HShl>(left, right);
break;
default:
UNREACHABLE();
}
}
if (instr->IsBinaryOperation()) {
HBinaryOperation* binop = HBinaryOperation::cast(instr);
binop->set_observed_input_representation(1, left_rep);
binop->set_observed_input_representation(2, right_rep);
binop->initialize_output_representation(result_rep);
if (graph()->info()->IsStub()) {
// Stub should not call into stub.
instr->SetFlag(HValue::kCannotBeTagged);
// And should truncate on HForceRepresentation already.
if (left->IsForceRepresentation()) {
left->CopyFlag(HValue::kTruncatingToSmi, instr);
left->CopyFlag(HValue::kTruncatingToInt32, instr);
}
if (right->IsForceRepresentation()) {
right->CopyFlag(HValue::kTruncatingToSmi, instr);
right->CopyFlag(HValue::kTruncatingToInt32, instr);
}
}
}
return instr;
}
// Check for the form (%_ClassOf(foo) === 'BarClass').
static bool IsClassOfTest(CompareOperation* expr) {
if (expr->op() != Token::EQ_STRICT) return false;
CallRuntime* call = expr->left()->AsCallRuntime();
if (call == NULL) return false;
Literal* literal = expr->right()->AsLiteral();
if (literal == NULL) return false;
if (!literal->value()->IsString()) return false;
if (call->is_jsruntime()) return false;
if (call->function()->function_id != Runtime::kInlineClassOf) return false;
DCHECK_EQ(call->arguments()->length(), 1);
return true;
}
void HOptimizedGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
switch (expr->op()) {
case Token::COMMA:
return VisitComma(expr);
case Token::OR:
case Token::AND:
return VisitLogicalExpression(expr);
default:
return VisitArithmeticExpression(expr);
}
}
void HOptimizedGraphBuilder::VisitComma(BinaryOperation* expr) {
CHECK_ALIVE(VisitForEffect(expr->left()));
// Visit the right subexpression in the same AST context as the entire
// expression.
Visit(expr->right());
}
void HOptimizedGraphBuilder::VisitLogicalExpression(BinaryOperation* expr) {
bool is_logical_and = expr->op() == Token::AND;
if (ast_context()->IsTest()) {
TestContext* context = TestContext::cast(ast_context());
// Translate left subexpression.
HBasicBlock* eval_right = graph()->CreateBasicBlock();
if (is_logical_and) {
CHECK_BAILOUT(VisitForControl(expr->left(),
eval_right,
context->if_false()));
} else {
CHECK_BAILOUT(VisitForControl(expr->left(),
context->if_true(),
eval_right));
}
// Translate right subexpression by visiting it in the same AST
// context as the entire expression.
CHECK(eval_right->HasPredecessor());
eval_right->SetJoinId(expr->RightId());
set_current_block(eval_right);
Visit(expr->right());
} else if (ast_context()->IsValue()) {
CHECK_ALIVE(VisitForValue(expr->left()));
DCHECK(current_block() != NULL);
HValue* left_value = Top();
// Short-circuit left values that always evaluate to the same boolean value.
if (expr->left()->ToBooleanIsTrue() || expr->left()->ToBooleanIsFalse()) {
// l (evals true) && r -> r
// l (evals true) || r -> l
// l (evals false) && r -> l
// l (evals false) || r -> r
if (is_logical_and == expr->left()->ToBooleanIsTrue()) {
Drop(1);
CHECK_ALIVE(VisitForValue(expr->right()));
}
return ast_context()->ReturnValue(Pop());
}
// We need an extra block to maintain edge-split form.
HBasicBlock* empty_block = graph()->CreateBasicBlock();
HBasicBlock* eval_right = graph()->CreateBasicBlock();
ToBooleanHints expected(expr->left()->to_boolean_types());
HBranch* test = is_logical_and
? New<HBranch>(left_value, expected, eval_right, empty_block)
: New<HBranch>(left_value, expected, empty_block, eval_right);
FinishCurrentBlock(test);
set_current_block(eval_right);
Drop(1); // Value of the left subexpression.
CHECK_BAILOUT(VisitForValue(expr->right()));
HBasicBlock* join_block =
CreateJoin(empty_block, current_block(), expr->id());
set_current_block(join_block);
return ast_context()->ReturnValue(Pop());
} else {
DCHECK(ast_context()->IsEffect());
// In an effect context, we don't need the value of the left subexpression,
// only its control flow and side effects. We need an extra block to
// maintain edge-split form.
HBasicBlock* empty_block = graph()->CreateBasicBlock();
HBasicBlock* right_block = graph()->CreateBasicBlock();
if (is_logical_and) {
CHECK_BAILOUT(VisitForControl(expr->left(), right_block, empty_block));
} else {
CHECK_BAILOUT(VisitForControl(expr->left(), empty_block, right_block));
}
// TODO(kmillikin): Find a way to fix this. It's ugly that there are
// actually two empty blocks (one here and one inserted by
// TestContext::BuildBranch, and that they both have an HSimulate though the
// second one is not a merge node, and that we really have no good AST ID to
// put on that first HSimulate.
// Technically, we should be able to handle the case when one side of
// the test is not connected, but this can trip up liveness analysis
// if we did not fully connect the test context based on some optimistic
// assumption. If such an assumption was violated, we would end up with
// an environment with optimized-out values. So we should always
// conservatively connect the test context.
CHECK(right_block->HasPredecessor());
CHECK(empty_block->HasPredecessor());
empty_block->SetJoinId(expr->id());
right_block->SetJoinId(expr->RightId());
set_current_block(right_block);
CHECK_BAILOUT(VisitForEffect(expr->right()));
right_block = current_block();
HBasicBlock* join_block =
CreateJoin(empty_block, right_block, expr->id());
set_current_block(join_block);
// We did not materialize any value in the predecessor environments,
// so there is no need to handle it here.
}
}
void HOptimizedGraphBuilder::VisitArithmeticExpression(BinaryOperation* expr) {
CHECK_ALIVE(VisitForValue(expr->left()));
CHECK_ALIVE(VisitForValue(expr->right()));
SetSourcePosition(expr->position());
HValue* right = Pop();
HValue* left = Pop();
HValue* result =
BuildBinaryOperation(expr, left, right,
ast_context()->IsEffect() ? NO_PUSH_BEFORE_SIMULATE
: PUSH_BEFORE_SIMULATE);
return ast_context()->ReturnValue(result);
}
void HOptimizedGraphBuilder::HandleLiteralCompareTypeof(CompareOperation* expr,
Expression* sub_expr,
Handle<String> check) {
CHECK_ALIVE(VisitForTypeOf(sub_expr));
SetSourcePosition(expr->position());
HValue* value = Pop();
HTypeofIsAndBranch* instr = New<HTypeofIsAndBranch>(value, check);
return ast_context()->ReturnControl(instr, expr->id());
}
namespace {
bool IsLiteralCompareStrict(Isolate* isolate, HValue* left, Token::Value op,
HValue* right) {
return op == Token::EQ_STRICT &&
((left->IsConstant() &&
!HConstant::cast(left)->handle(isolate)->IsNumber() &&
!HConstant::cast(left)->handle(isolate)->IsString()) ||
(right->IsConstant() &&
!HConstant::cast(right)->handle(isolate)->IsNumber() &&
!HConstant::cast(right)->handle(isolate)->IsString()));
}
} // namespace
void HOptimizedGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
if (!is_tracking_positions()) SetSourcePosition(expr->position());
// Check for a few fast cases. The AST visiting behavior must be in sync
// with the full codegen: We don't push both left and right values onto
// the expression stack when one side is a special-case literal.
Expression* sub_expr = NULL;
Literal* literal;
if (expr->IsLiteralCompareTypeof(&sub_expr, &literal)) {
return HandleLiteralCompareTypeof(expr, sub_expr,
Handle<String>::cast(literal->value()));
}
if (expr->IsLiteralCompareUndefined(&sub_expr)) {
return HandleLiteralCompareNil(expr, sub_expr, kUndefinedValue);
}
if (expr->IsLiteralCompareNull(&sub_expr)) {
return HandleLiteralCompareNil(expr, sub_expr, kNullValue);
}
if (IsClassOfTest(expr)) {
CallRuntime* call = expr->left()->AsCallRuntime();
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
Literal* literal = expr->right()->AsLiteral();
Handle<String> rhs = Handle<String>::cast(literal->value());
HClassOfTestAndBranch* instr = New<HClassOfTestAndBranch>(value, rhs);
return ast_context()->ReturnControl(instr, expr->id());
}
AstType* left_type = bounds_.get(expr->left()).lower;
AstType* right_type = bounds_.get(expr->right()).lower;
AstType* combined_type = expr->combined_type();
CHECK_ALIVE(VisitForValue(expr->left()));
CHECK_ALIVE(VisitForValue(expr->right()));
HValue* right = Pop();
HValue* left = Pop();
Token::Value op = expr->op();
if (IsLiteralCompareStrict(isolate(), left, op, right)) {
HCompareObjectEqAndBranch* result =
New<HCompareObjectEqAndBranch>(left, right);
return ast_context()->ReturnControl(result, expr->id());
}
if (op == Token::INSTANCEOF) {
// Check to see if the rhs of the instanceof is a known function.
if (right->IsConstant() &&
HConstant::cast(right)->handle(isolate())->IsJSFunction()) {
Handle<JSFunction> function =
Handle<JSFunction>::cast(HConstant::cast(right)->handle(isolate()));
// Make sure that the {function} already has a meaningful initial map
// (i.e. we constructed at least one instance using the constructor
// {function}), and has an instance as .prototype.
if (function->has_initial_map() &&
!function->map()->has_non_instance_prototype()) {
// Lookup @@hasInstance on the {function}.
Handle<Map> function_map(function->map(), isolate());
PropertyAccessInfo has_instance(
this, LOAD, function_map,
isolate()->factory()->has_instance_symbol());
// Check if we are using the Function.prototype[@@hasInstance].
if (has_instance.CanAccessMonomorphic() &&
has_instance.IsDataConstant() &&
has_instance.constant().is_identical_to(
isolate()->function_has_instance())) {
// Add appropriate receiver map check and prototype chain
// checks to guard the @@hasInstance lookup chain.
AddCheckMap(right, function_map);
if (has_instance.has_holder()) {
Handle<JSObject> prototype(
JSObject::cast(has_instance.map()->prototype()), isolate());
BuildCheckPrototypeMaps(prototype, has_instance.holder());
}
// Perform the prototype chain walk.
Handle<Map> initial_map(function->initial_map(), isolate());
top_info()->dependencies()->AssumeInitialMapCantChange(initial_map);
HInstruction* prototype =
Add<HConstant>(handle(initial_map->prototype(), isolate()));
HHasInPrototypeChainAndBranch* result =
New<HHasInPrototypeChainAndBranch>(left, prototype);
return ast_context()->ReturnControl(result, expr->id());
}
}
}
Callable callable = CodeFactory::InstanceOf(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {left, right};
HCallWithDescriptor* result = New<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
result->set_type(HType::Boolean());
return ast_context()->ReturnInstruction(result, expr->id());
} else if (op == Token::IN) {
Callable callable = CodeFactory::HasProperty(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {left, right};
HInstruction* result =
New<HCallWithDescriptor>(stub, 0, callable.descriptor(),
Vector<HValue*>(values, arraysize(values)));
return ast_context()->ReturnInstruction(result, expr->id());
}
PushBeforeSimulateBehavior push_behavior =
ast_context()->IsEffect() ? NO_PUSH_BEFORE_SIMULATE
: PUSH_BEFORE_SIMULATE;
HControlInstruction* compare = BuildCompareInstruction(
op, left, right, left_type, right_type, combined_type,
ScriptPositionToSourcePosition(expr->left()->position()),
ScriptPositionToSourcePosition(expr->right()->position()),
push_behavior, expr->id());
if (compare == NULL) return; // Bailed out.
return ast_context()->ReturnControl(compare, expr->id());
}
HControlInstruction* HOptimizedGraphBuilder::BuildCompareInstruction(
Token::Value op, HValue* left, HValue* right, AstType* left_type,
AstType* right_type, AstType* combined_type, SourcePosition left_position,
SourcePosition right_position, PushBeforeSimulateBehavior push_sim_result,
BailoutId bailout_id) {
// Cases handled below depend on collected type feedback. They should
// soft deoptimize when there is no type feedback.
if (!combined_type->IsInhabited()) {
Add<HDeoptimize>(
DeoptimizeReason::
kInsufficientTypeFeedbackForCombinedTypeOfBinaryOperation,
Deoptimizer::SOFT);
combined_type = left_type = right_type = AstType::Any();
}
Representation left_rep = RepresentationFor(left_type);
Representation right_rep = RepresentationFor(right_type);
Representation combined_rep = RepresentationFor(combined_type);
if (combined_type->Is(AstType::Receiver())) {
if (Token::IsEqualityOp(op)) {
// HCompareObjectEqAndBranch can only deal with object, so
// exclude numbers.
if ((left->IsConstant() &&
HConstant::cast(left)->HasNumberValue()) ||
(right->IsConstant() &&
HConstant::cast(right)->HasNumberValue())) {
Add<HDeoptimize>(
DeoptimizeReason::kTypeMismatchBetweenFeedbackAndConstant,
Deoptimizer::SOFT);
// The caller expects a branch instruction, so make it happy.
return New<HBranch>(graph()->GetConstantTrue());
}
if (op == Token::EQ) {
// For abstract equality we need to check both sides are receivers.
if (combined_type->IsClass()) {
Handle<Map> map = combined_type->AsClass()->Map();
AddCheckMap(left, map);
AddCheckMap(right, map);
} else {
BuildCheckHeapObject(left);
Add<HCheckInstanceType>(left, HCheckInstanceType::IS_JS_RECEIVER);
BuildCheckHeapObject(right);
Add<HCheckInstanceType>(right, HCheckInstanceType::IS_JS_RECEIVER);
}
} else {
// For strict equality we only need to check one side.
HValue* operand_to_check =
left->block()->block_id() < right->block()->block_id() ? left
: right;
if (combined_type->IsClass()) {
Handle<Map> map = combined_type->AsClass()->Map();
AddCheckMap(operand_to_check, map);
} else {
BuildCheckHeapObject(operand_to_check);
Add<HCheckInstanceType>(operand_to_check,
HCheckInstanceType::IS_JS_RECEIVER);
}
}
HCompareObjectEqAndBranch* result =
New<HCompareObjectEqAndBranch>(left, right);
return result;
} else {
if (combined_type->IsClass()) {
// TODO(bmeurer): This is an optimized version of an x < y, x > y,
// x <= y or x >= y, where both x and y are spec objects with the
// same map. The CompareIC collects this map for us. So if we know
// that there's no @@toPrimitive on the map (including the prototype
// chain), and both valueOf and toString are the default initial
// implementations (on the %ObjectPrototype%), then we can reduce
// the comparison to map checks on x and y, because the comparison
// will turn into a comparison of "[object CLASS]" to itself (the
// default outcome of toString, since valueOf returns a spec object).
// This is pretty much adhoc, so in TurboFan we could do a lot better
// and inline the interesting parts of ToPrimitive (actually we could
// even do that in Crankshaft but we don't want to waste too much
// time on this now).
DCHECK(Token::IsOrderedRelationalCompareOp(op));
Handle<Map> map = combined_type->AsClass()->Map();
PropertyAccessInfo value_of(this, LOAD, map,
isolate()->factory()->valueOf_string());
PropertyAccessInfo to_primitive(
this, LOAD, map, isolate()->factory()->to_primitive_symbol());
PropertyAccessInfo to_string(this, LOAD, map,
isolate()->factory()->toString_string());
PropertyAccessInfo to_string_tag(
this, LOAD, map, isolate()->factory()->to_string_tag_symbol());
if (to_primitive.CanAccessMonomorphic() && !to_primitive.IsFound() &&
to_string_tag.CanAccessMonomorphic() &&
(!to_string_tag.IsFound() || to_string_tag.IsData() ||
to_string_tag.IsDataConstant()) &&
value_of.CanAccessMonomorphic() && value_of.IsDataConstant() &&
value_of.constant().is_identical_to(isolate()->object_value_of()) &&
to_string.CanAccessMonomorphic() && to_string.IsDataConstant() &&
to_string.constant().is_identical_to(
isolate()->object_to_string())) {
// We depend on the prototype chain to stay the same, because we
// also need to deoptimize when someone installs @@toPrimitive
// or @@toStringTag somewhere in the prototype chain.
Handle<Object> prototype(map->prototype(), isolate());
if (prototype->IsJSObject()) {
BuildCheckPrototypeMaps(Handle<JSObject>::cast(prototype),
Handle<JSObject>::null());
}
AddCheckMap(left, map);
AddCheckMap(right, map);
// The caller expects a branch instruction, so make it happy.
return New<HBranch>(
graph()->GetConstantBool(op == Token::LTE || op == Token::GTE));
}
}
Bailout(kUnsupportedNonPrimitiveCompare);
return NULL;
}
} else if (combined_type->Is(AstType::InternalizedString()) &&
Token::IsEqualityOp(op)) {
// If we have a constant argument, it should be consistent with the type
// feedback (otherwise we fail assertions in HCompareObjectEqAndBranch).
if ((left->IsConstant() &&
!HConstant::cast(left)->HasInternalizedStringValue()) ||
(right->IsConstant() &&
!HConstant::cast(right)->HasInternalizedStringValue())) {
Add<HDeoptimize>(
DeoptimizeReason::kTypeMismatchBetweenFeedbackAndConstant,
Deoptimizer::SOFT);
// The caller expects a branch instruction, so make it happy.
return New<HBranch>(graph()->GetConstantTrue());
}
BuildCheckHeapObject(left);
Add<HCheckInstanceType>(left, HCheckInstanceType::IS_INTERNALIZED_STRING);
BuildCheckHeapObject(right);
Add<HCheckInstanceType>(right, HCheckInstanceType::IS_INTERNALIZED_STRING);
HCompareObjectEqAndBranch* result =
New<HCompareObjectEqAndBranch>(left, right);
return result;
} else if (combined_type->Is(AstType::String())) {
BuildCheckHeapObject(left);
Add<HCheckInstanceType>(left, HCheckInstanceType::IS_STRING);
BuildCheckHeapObject(right);
Add<HCheckInstanceType>(right, HCheckInstanceType::IS_STRING);
HStringCompareAndBranch* result =
New<HStringCompareAndBranch>(left, right, op);
return result;
} else if (combined_type->Is(AstType::Boolean())) {
AddCheckMap(left, isolate()->factory()->boolean_map());
AddCheckMap(right, isolate()->factory()->boolean_map());
if (Token::IsEqualityOp(op)) {
HCompareObjectEqAndBranch* result =
New<HCompareObjectEqAndBranch>(left, right);
return result;
}
left = Add<HLoadNamedField>(
left, nullptr,
HObjectAccess::ForOddballToNumber(Representation::Smi()));
right = Add<HLoadNamedField>(
right, nullptr,
HObjectAccess::ForOddballToNumber(Representation::Smi()));
HCompareNumericAndBranch* result =
New<HCompareNumericAndBranch>(left, right, op);
return result;
} else {
if (op == Token::EQ) {
if (left->IsConstant() &&
HConstant::cast(left)->GetInstanceType() == ODDBALL_TYPE &&
HConstant::cast(left)->IsUndetectable()) {
return New<HIsUndetectableAndBranch>(right);
}
if (right->IsConstant() &&
HConstant::cast(right)->GetInstanceType() == ODDBALL_TYPE &&
HConstant::cast(right)->IsUndetectable()) {
return New<HIsUndetectableAndBranch>(left);
}
}
if (combined_rep.IsTagged() || combined_rep.IsNone()) {
HCompareGeneric* result = Add<HCompareGeneric>(left, right, op);
result->set_observed_input_representation(1, left_rep);
result->set_observed_input_representation(2, right_rep);
if (result->HasObservableSideEffects()) {
if (push_sim_result == PUSH_BEFORE_SIMULATE) {
Push(result);
AddSimulate(bailout_id, REMOVABLE_SIMULATE);
Drop(1);
} else {
AddSimulate(bailout_id, REMOVABLE_SIMULATE);
}
}
// TODO(jkummerow): Can we make this more efficient?
HBranch* branch = New<HBranch>(result);
return branch;
} else {
HCompareNumericAndBranch* result =
New<HCompareNumericAndBranch>(left, right, op);
result->set_observed_input_representation(left_rep, right_rep);
return result;
}
}
}
void HOptimizedGraphBuilder::HandleLiteralCompareNil(CompareOperation* expr,
Expression* sub_expr,
NilValue nil) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
DCHECK(expr->op() == Token::EQ || expr->op() == Token::EQ_STRICT);
if (!is_tracking_positions()) SetSourcePosition(expr->position());
CHECK_ALIVE(VisitForValue(sub_expr));
HValue* value = Pop();
HControlInstruction* instr;
if (expr->op() == Token::EQ_STRICT) {
HConstant* nil_constant = nil == kNullValue
? graph()->GetConstantNull()
: graph()->GetConstantUndefined();
instr = New<HCompareObjectEqAndBranch>(value, nil_constant);
} else {
DCHECK_EQ(Token::EQ, expr->op());
instr = New<HIsUndetectableAndBranch>(value);
}
return ast_context()->ReturnControl(instr, expr->id());
}
void HOptimizedGraphBuilder::VisitSpread(Spread* expr) { UNREACHABLE(); }
void HOptimizedGraphBuilder::VisitEmptyParentheses(EmptyParentheses* expr) {
UNREACHABLE();
}
void HOptimizedGraphBuilder::VisitGetIterator(GetIterator* expr) {
UNREACHABLE();
}
void HOptimizedGraphBuilder::VisitImportCallExpression(
ImportCallExpression* expr) {
UNREACHABLE();
}
HValue* HOptimizedGraphBuilder::AddThisFunction() {
return AddInstruction(BuildThisFunction());
}
HInstruction* HOptimizedGraphBuilder::BuildThisFunction() {
// If we share optimized code between different closures, the
// this-function is not a constant, except inside an inlined body.
if (function_state()->outer() != NULL) {
return New<HConstant>(
function_state()->compilation_info()->closure());
} else {
return New<HThisFunction>();
}
}
HInstruction* HOptimizedGraphBuilder::BuildFastLiteral(
Handle<JSObject> boilerplate_object,
AllocationSiteUsageContext* site_context) {
NoObservableSideEffectsScope no_effects(this);
Handle<Map> initial_map(boilerplate_object->map());
InstanceType instance_type = initial_map->instance_type();
DCHECK(instance_type == JS_ARRAY_TYPE || instance_type == JS_OBJECT_TYPE);
HType type = instance_type == JS_ARRAY_TYPE
? HType::JSArray() : HType::JSObject();
HValue* object_size_constant = Add<HConstant>(initial_map->instance_size());
PretenureFlag pretenure_flag = NOT_TENURED;
Handle<AllocationSite> top_site(*site_context->top(), isolate());
if (FLAG_allocation_site_pretenuring) {
pretenure_flag = top_site->GetPretenureMode();
}
Handle<AllocationSite> current_site(*site_context->current(), isolate());
if (*top_site == *current_site) {
// We install a dependency for pretenuring only on the outermost literal.
top_info()->dependencies()->AssumeTenuringDecision(top_site);
}
top_info()->dependencies()->AssumeTransitionStable(current_site);
HInstruction* object =
Add<HAllocate>(object_size_constant, type, pretenure_flag, instance_type,
graph()->GetConstant0(), top_site);
// If allocation folding reaches kMaxRegularHeapObjectSize the
// elements array may not get folded into the object. Hence, we set the
// elements pointer to empty fixed array and let store elimination remove
// this store in the folding case.
HConstant* empty_fixed_array = Add<HConstant>(
isolate()->factory()->empty_fixed_array());
Add<HStoreNamedField>(object, HObjectAccess::ForElementsPointer(),
empty_fixed_array);
BuildEmitObjectHeader(boilerplate_object, object);
// Similarly to the elements pointer, there is no guarantee that all
// property allocations can get folded, so pre-initialize all in-object
// properties to a safe value.
BuildInitializeInobjectProperties(object, initial_map);
// Copy in-object properties.
if (initial_map->NumberOfFields() != 0 ||
initial_map->unused_property_fields() > 0) {
BuildEmitInObjectProperties(boilerplate_object, object, site_context,
pretenure_flag);
}
// Copy elements.
Handle<FixedArrayBase> elements(boilerplate_object->elements());
int elements_size = (elements->length() > 0 &&
elements->map() != isolate()->heap()->fixed_cow_array_map()) ?
elements->Size() : 0;
if (pretenure_flag == TENURED &&
elements->map() == isolate()->heap()->fixed_cow_array_map() &&
isolate()->heap()->InNewSpace(*elements)) {
// If we would like to pretenure a fixed cow array, we must ensure that the
// array is already in old space, otherwise we'll create too many old-to-
// new-space pointers (overflowing the store buffer).
elements = Handle<FixedArrayBase>(
isolate()->factory()->CopyAndTenureFixedCOWArray(
Handle<FixedArray>::cast(elements)));
boilerplate_object->set_elements(*elements);
}
HInstruction* object_elements = NULL;
if (elements_size > 0) {
HValue* object_elements_size = Add<HConstant>(elements_size);
InstanceType instance_type = boilerplate_object->HasFastDoubleElements()
? FIXED_DOUBLE_ARRAY_TYPE : FIXED_ARRAY_TYPE;
object_elements = Add<HAllocate>(object_elements_size, HType::HeapObject(),
pretenure_flag, instance_type,
graph()->GetConstant0(), top_site);
BuildEmitElements(boilerplate_object, elements, object_elements,
site_context);
Add<HStoreNamedField>(object, HObjectAccess::ForElementsPointer(),
object_elements);
} else {
Handle<Object> elements_field =
Handle<Object>(boilerplate_object->elements(), isolate());
HInstruction* object_elements_cow = Add<HConstant>(elements_field);
Add<HStoreNamedField>(object, HObjectAccess::ForElementsPointer(),
object_elements_cow);
}
return object;
}
void HOptimizedGraphBuilder::BuildEmitObjectHeader(
Handle<JSObject> boilerplate_object,
HInstruction* object) {
DCHECK(boilerplate_object->properties()->length() == 0);
Handle<Map> boilerplate_object_map(boilerplate_object->map());
AddStoreMapConstant(object, boilerplate_object_map);
Handle<Object> properties_field =
Handle<Object>(boilerplate_object->properties(), isolate());
DCHECK(*properties_field == isolate()->heap()->empty_fixed_array());
HInstruction* properties = Add<HConstant>(properties_field);
HObjectAccess access = HObjectAccess::ForPropertiesPointer();
Add<HStoreNamedField>(object, access, properties);
if (boilerplate_object->IsJSArray()) {
Handle<JSArray> boilerplate_array =
Handle<JSArray>::cast(boilerplate_object);
Handle<Object> length_field =
Handle<Object>(boilerplate_array->length(), isolate());
HInstruction* length = Add<HConstant>(length_field);
DCHECK(boilerplate_array->length()->IsSmi());
Add<HStoreNamedField>(object, HObjectAccess::ForArrayLength(
boilerplate_array->GetElementsKind()), length);
}
}
void HOptimizedGraphBuilder::BuildEmitInObjectProperties(
Handle<JSObject> boilerplate_object,
HInstruction* object,
AllocationSiteUsageContext* site_context,
PretenureFlag pretenure_flag) {
Handle<Map> boilerplate_map(boilerplate_object->map());
Handle<DescriptorArray> descriptors(boilerplate_map->instance_descriptors());
int limit = boilerplate_map->NumberOfOwnDescriptors();
int copied_fields = 0;
for (int i = 0; i < limit; i++) {
PropertyDetails details = descriptors->GetDetails(i);
if (details.location() != kField) continue;
DCHECK_EQ(kData, details.kind());
copied_fields++;
FieldIndex field_index = FieldIndex::ForDescriptor(*boilerplate_map, i);
int property_offset = field_index.offset();
Handle<Name> name(descriptors->GetKey(i));
// The access for the store depends on the type of the boilerplate.
HObjectAccess access = boilerplate_object->IsJSArray() ?
HObjectAccess::ForJSArrayOffset(property_offset) :
HObjectAccess::ForMapAndOffset(boilerplate_map, property_offset);
if (boilerplate_object->IsUnboxedDoubleField(field_index)) {
CHECK(!boilerplate_object->IsJSArray());
double value = boilerplate_object->RawFastDoublePropertyAt(field_index);
access = access.WithRepresentation(Representation::Double());
Add<HStoreNamedField>(object, access, Add<HConstant>(value));
continue;
}
Handle<Object> value(boilerplate_object->RawFastPropertyAt(field_index),
isolate());
if (value->IsJSObject()) {
Handle<JSObject> value_object = Handle<JSObject>::cast(value);
Handle<AllocationSite> current_site = site_context->EnterNewScope();
HInstruction* result =
BuildFastLiteral(value_object, site_context);
site_context->ExitScope(current_site, value_object);
Add<HStoreNamedField>(object, access, result);
} else {
Representation representation = details.representation();
HInstruction* value_instruction;
if (representation.IsDouble()) {
// Allocate a HeapNumber box and store the value into it.
HValue* heap_number_constant = Add<HConstant>(HeapNumber::kSize);
HInstruction* double_box = Add<HAllocate>(
heap_number_constant, HType::HeapObject(), pretenure_flag,
MUTABLE_HEAP_NUMBER_TYPE, graph()->GetConstant0());
AddStoreMapConstant(double_box,
isolate()->factory()->mutable_heap_number_map());
// Unwrap the mutable heap number from the boilerplate.
HValue* double_value =
Add<HConstant>(Handle<HeapNumber>::cast(value)->value());
Add<HStoreNamedField>(
double_box, HObjectAccess::ForHeapNumberValue(), double_value);
value_instruction = double_box;
} else if (representation.IsSmi()) {
value_instruction = value->IsUninitialized(isolate())
? graph()->GetConstant0()
: Add<HConstant>(value);
// Ensure that value is stored as smi.
access = access.WithRepresentation(representation);
} else {
value_instruction = Add<HConstant>(value);
}
Add<HStoreNamedField>(object, access, value_instruction);
}
}
int inobject_properties = boilerplate_object->map()->GetInObjectProperties();
HInstruction* value_instruction =
Add<HConstant>(isolate()->factory()->one_pointer_filler_map());
for (int i = copied_fields; i < inobject_properties; i++) {
DCHECK(boilerplate_object->IsJSObject());
int property_offset = boilerplate_object->GetInObjectPropertyOffset(i);
HObjectAccess access =
HObjectAccess::ForMapAndOffset(boilerplate_map, property_offset);
Add<HStoreNamedField>(object, access, value_instruction);
}
}
void HOptimizedGraphBuilder::BuildEmitElements(
Handle<JSObject> boilerplate_object,
Handle<FixedArrayBase> elements,
HValue* object_elements,
AllocationSiteUsageContext* site_context) {
ElementsKind kind = boilerplate_object->map()->elements_kind();
int elements_length = elements->length();
HValue* object_elements_length = Add<HConstant>(elements_length);
BuildInitializeElementsHeader(object_elements, kind, object_elements_length);
// Copy elements backing store content.
if (elements->IsFixedDoubleArray()) {
BuildEmitFixedDoubleArray(elements, kind, object_elements);
} else if (elements->IsFixedArray()) {
BuildEmitFixedArray(elements, kind, object_elements,
site_context);
} else {
UNREACHABLE();
}
}
void HOptimizedGraphBuilder::BuildEmitFixedDoubleArray(
Handle<FixedArrayBase> elements,
ElementsKind kind,
HValue* object_elements) {
HInstruction* boilerplate_elements = Add<HConstant>(elements);
int elements_length = elements->length();
for (int i = 0; i < elements_length; i++) {
HValue* key_constant = Add<HConstant>(i);
HInstruction* value_instruction =
Add<HLoadKeyed>(boilerplate_elements, key_constant, nullptr, nullptr,
kind, ALLOW_RETURN_HOLE);
HInstruction* store = Add<HStoreKeyed>(object_elements, key_constant,
value_instruction, nullptr, kind);
store->SetFlag(HValue::kTruncatingToNumber);
}
}
void HOptimizedGraphBuilder::BuildEmitFixedArray(
Handle<FixedArrayBase> elements,
ElementsKind kind,
HValue* object_elements,
AllocationSiteUsageContext* site_context) {
HInstruction* boilerplate_elements = Add<HConstant>(elements);
int elements_length = elements->length();
Handle<FixedArray> fast_elements = Handle<FixedArray>::cast(elements);
for (int i = 0; i < elements_length; i++) {
Handle<Object> value(fast_elements->get(i), isolate());
HValue* key_constant = Add<HConstant>(i);
if (value->IsJSObject()) {
Handle<JSObject> value_object = Handle<JSObject>::cast(value);
Handle<AllocationSite> current_site = site_context->EnterNewScope();
HInstruction* result =
BuildFastLiteral(value_object, site_context);
site_context->ExitScope(current_site, value_object);
Add<HStoreKeyed>(object_elements, key_constant, result, nullptr, kind);
} else {
ElementsKind copy_kind =
kind == FAST_HOLEY_SMI_ELEMENTS ? FAST_HOLEY_ELEMENTS : kind;
HInstruction* value_instruction =
Add<HLoadKeyed>(boilerplate_elements, key_constant, nullptr, nullptr,
copy_kind, ALLOW_RETURN_HOLE);
Add<HStoreKeyed>(object_elements, key_constant, value_instruction,
nullptr, copy_kind);
}
}
}
void HOptimizedGraphBuilder::VisitThisFunction(ThisFunction* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
HInstruction* instr = BuildThisFunction();
return ast_context()->ReturnInstruction(instr, expr->id());
}
void HOptimizedGraphBuilder::VisitSuperPropertyReference(
SuperPropertyReference* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kSuperReference);
}
void HOptimizedGraphBuilder::VisitSuperCallReference(SuperCallReference* expr) {
DCHECK(!HasStackOverflow());
DCHECK(current_block() != NULL);
DCHECK(current_block()->HasPredecessor());
return Bailout(kSuperReference);
}
void HOptimizedGraphBuilder::VisitDeclarations(
Declaration::List* declarations) {
DCHECK(globals_.is_empty());
AstVisitor<HOptimizedGraphBuilder>::VisitDeclarations(declarations);
if (!globals_.is_empty()) {
Handle<FixedArray> array =
isolate()->factory()->NewFixedArray(globals_.length(), TENURED);
for (int i = 0; i < globals_.length(); ++i) array->set(i, *globals_.at(i));
int flags = current_info()->GetDeclareGlobalsFlags();
Handle<FeedbackVector> vector(current_feedback_vector(), isolate());
Add<HDeclareGlobals>(array, flags, vector);
globals_.Rewind(0);
}
}
void HOptimizedGraphBuilder::VisitVariableDeclaration(
VariableDeclaration* declaration) {
VariableProxy* proxy = declaration->proxy();
Variable* variable = proxy->var();
switch (variable->location()) {
case VariableLocation::UNALLOCATED: {
DCHECK(!variable->binding_needs_init());
globals_.Add(variable->name(), zone());
FeedbackSlot slot = proxy->VariableFeedbackSlot();
DCHECK(!slot.IsInvalid());
globals_.Add(handle(Smi::FromInt(slot.ToInt()), isolate()), zone());
globals_.Add(isolate()->factory()->undefined_value(), zone());
globals_.Add(isolate()->factory()->undefined_value(), zone());
return;
}
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL:
if (variable->binding_needs_init()) {
HValue* value = graph()->GetConstantHole();
environment()->Bind(variable, value);
}
break;
case VariableLocation::CONTEXT:
if (variable->binding_needs_init()) {
HValue* value = graph()->GetConstantHole();
HValue* context = environment()->context();
HStoreContextSlot* store = Add<HStoreContextSlot>(
context, variable->index(), HStoreContextSlot::kNoCheck, value);
if (store->HasObservableSideEffects()) {
Add<HSimulate>(proxy->id(), REMOVABLE_SIMULATE);
}
}
break;
case VariableLocation::LOOKUP:
return Bailout(kUnsupportedLookupSlotInDeclaration);
case VariableLocation::MODULE:
UNREACHABLE();
}
}
void HOptimizedGraphBuilder::VisitFunctionDeclaration(
FunctionDeclaration* declaration) {
VariableProxy* proxy = declaration->proxy();
Variable* variable = proxy->var();
switch (variable->location()) {
case VariableLocation::UNALLOCATED: {
globals_.Add(variable->name(), zone());
FeedbackSlot slot = proxy->VariableFeedbackSlot();
DCHECK(!slot.IsInvalid());
globals_.Add(handle(Smi::FromInt(slot.ToInt()), isolate()), zone());
// We need the slot where the literals array lives, too.
slot = declaration->fun()->LiteralFeedbackSlot();
DCHECK(!slot.IsInvalid());
globals_.Add(handle(Smi::FromInt(slot.ToInt()), isolate()), zone());
Handle<SharedFunctionInfo> function = Compiler::GetSharedFunctionInfo(
declaration->fun(), current_info()->script(), top_info());
// Check for stack-overflow exception.
if (function.is_null()) return SetStackOverflow();
globals_.Add(function, zone());
return;
}
case VariableLocation::PARAMETER:
case VariableLocation::LOCAL: {
CHECK_ALIVE(VisitForValue(declaration->fun()));
HValue* value = Pop();
BindIfLive(variable, value);
break;
}
case VariableLocation::CONTEXT: {
CHECK_ALIVE(VisitForValue(declaration->fun()));
HValue* value = Pop();
HValue* context = environment()->context();
HStoreContextSlot* store = Add<HStoreContextSlot>(
context, variable->index(), HStoreContextSlot::kNoCheck, value);
if (store->HasObservableSideEffects()) {
Add<HSimulate>(proxy->id(), REMOVABLE_SIMULATE);
}
break;
}
case VariableLocation::LOOKUP:
return Bailout(kUnsupportedLookupSlotInDeclaration);
case VariableLocation::MODULE:
UNREACHABLE();
}
}
void HOptimizedGraphBuilder::VisitRewritableExpression(
RewritableExpression* node) {
CHECK_ALIVE(Visit(node->expression()));
}
// Generators for inline runtime functions.
// Support for types.
void HOptimizedGraphBuilder::GenerateIsSmi(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HIsSmiAndBranch* result = New<HIsSmiAndBranch>(value);
return ast_context()->ReturnControl(result, call->id());
}
void HOptimizedGraphBuilder::GenerateIsJSReceiver(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HHasInstanceTypeAndBranch* result =
New<HHasInstanceTypeAndBranch>(value,
FIRST_JS_RECEIVER_TYPE,
LAST_JS_RECEIVER_TYPE);
return ast_context()->ReturnControl(result, call->id());
}
void HOptimizedGraphBuilder::GenerateIsArray(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HHasInstanceTypeAndBranch* result =
New<HHasInstanceTypeAndBranch>(value, JS_ARRAY_TYPE);
return ast_context()->ReturnControl(result, call->id());
}
void HOptimizedGraphBuilder::GenerateIsTypedArray(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HHasInstanceTypeAndBranch* result =
New<HHasInstanceTypeAndBranch>(value, JS_TYPED_ARRAY_TYPE);
return ast_context()->ReturnControl(result, call->id());
}
void HOptimizedGraphBuilder::GenerateToInteger(CallRuntime* call) {
DCHECK_EQ(1, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* input = Pop();
if (input->type().IsSmi()) {
return ast_context()->ReturnValue(input);
} else {
Callable callable = CodeFactory::ToInteger(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {input};
HInstruction* result = New<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
return ast_context()->ReturnInstruction(result, call->id());
}
}
void HOptimizedGraphBuilder::GenerateToObject(CallRuntime* call) {
DCHECK_EQ(1, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HValue* result = BuildToObject(value);
return ast_context()->ReturnValue(result);
}
void HOptimizedGraphBuilder::GenerateToString(CallRuntime* call) {
DCHECK_EQ(1, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* input = Pop();
if (input->type().IsString()) {
return ast_context()->ReturnValue(input);
} else {
Callable callable = CodeFactory::ToString(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {input};
HInstruction* result = New<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
return ast_context()->ReturnInstruction(result, call->id());
}
}
void HOptimizedGraphBuilder::GenerateToLength(CallRuntime* call) {
DCHECK_EQ(1, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
Callable callable = CodeFactory::ToLength(isolate());
HValue* input = Pop();
HValue* stub = Add<HConstant>(callable.code());
HValue* values[] = {input};
HInstruction* result = New<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
return ast_context()->ReturnInstruction(result, call->id());
}
void HOptimizedGraphBuilder::GenerateToNumber(CallRuntime* call) {
DCHECK_EQ(1, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
Callable callable = CodeFactory::ToNumber(isolate());
HValue* input = Pop();
HValue* result = BuildToNumber(input);
if (result->HasObservableSideEffects()) {
if (!ast_context()->IsEffect()) Push(result);
Add<HSimulate>(call->id(), REMOVABLE_SIMULATE);
if (!ast_context()->IsEffect()) result = Pop();
}
return ast_context()->ReturnValue(result);
}
void HOptimizedGraphBuilder::GenerateIsJSProxy(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* value = Pop();
HIfContinuation continuation;
IfBuilder if_proxy(this);
HValue* smicheck = if_proxy.IfNot<HIsSmiAndBranch>(value);
if_proxy.And();
HValue* map = Add<HLoadNamedField>(value, smicheck, HObjectAccess::ForMap());
HValue* instance_type =
Add<HLoadNamedField>(map, nullptr, HObjectAccess::ForMapInstanceType());
if_proxy.If<HCompareNumericAndBranch>(
instance_type, Add<HConstant>(JS_PROXY_TYPE), Token::EQ);
if_proxy.CaptureContinuation(&continuation);
return ast_context()->ReturnContinuation(&continuation, call->id());
}
void HOptimizedGraphBuilder::GenerateHasFastPackedElements(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* object = Pop();
HIfContinuation continuation(graph()->CreateBasicBlock(),
graph()->CreateBasicBlock());
IfBuilder if_not_smi(this);
if_not_smi.IfNot<HIsSmiAndBranch>(object);
if_not_smi.Then();
{
NoObservableSideEffectsScope no_effects(this);
IfBuilder if_fast_packed(this);
HValue* elements_kind = BuildGetElementsKind(object);
if_fast_packed.If<HCompareNumericAndBranch>(
elements_kind, Add<HConstant>(FAST_SMI_ELEMENTS), Token::EQ);
if_fast_packed.Or();
if_fast_packed.If<HCompareNumericAndBranch>(
elements_kind, Add<HConstant>(FAST_ELEMENTS), Token::EQ);
if_fast_packed.Or();
if_fast_packed.If<HCompareNumericAndBranch>(
elements_kind, Add<HConstant>(FAST_DOUBLE_ELEMENTS), Token::EQ);
if_fast_packed.JoinContinuation(&continuation);
}
if_not_smi.JoinContinuation(&continuation);
return ast_context()->ReturnContinuation(&continuation, call->id());
}
// Fast support for charCodeAt(n).
void HOptimizedGraphBuilder::GenerateStringCharCodeAt(CallRuntime* call) {
DCHECK(call->arguments()->length() == 2);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
CHECK_ALIVE(VisitForValue(call->arguments()->at(1)));
HValue* index = Pop();
HValue* string = Pop();
HInstruction* result = BuildStringCharCodeAt(string, index);
return ast_context()->ReturnInstruction(result, call->id());
}
// Fast support for SubString.
void HOptimizedGraphBuilder::GenerateSubString(CallRuntime* call) {
DCHECK_EQ(3, call->arguments()->length());
CHECK_ALIVE(VisitExpressions(call->arguments()));
Callable callable = CodeFactory::SubString(isolate());
HValue* stub = Add<HConstant>(callable.code());
HValue* to = Pop();
HValue* from = Pop();
HValue* string = Pop();
HValue* values[] = {string, from, to};
HInstruction* result = New<HCallWithDescriptor>(
stub, 0, callable.descriptor(), ArrayVector(values));
result->set_type(HType::String());
return ast_context()->ReturnInstruction(result, call->id());
}
// Fast support for calls.
void HOptimizedGraphBuilder::GenerateCall(CallRuntime* call) {
DCHECK_LE(2, call->arguments()->length());
CHECK_ALIVE(VisitExpressions(call->arguments()));
CallTrampolineDescriptor descriptor(isolate());
PushArgumentsFromEnvironment(call->arguments()->length() - 1);
HValue* trampoline = Add<HConstant>(isolate()->builtins()->Call());
HValue* target = Pop();
HValue* values[] = {target, Add<HConstant>(call->arguments()->length() - 2)};
HInstruction* result =
New<HCallWithDescriptor>(trampoline, call->arguments()->length() - 1,
descriptor, ArrayVector(values));
return ast_context()->ReturnInstruction(result, call->id());
}
void HOptimizedGraphBuilder::GenerateFixedArrayGet(CallRuntime* call) {
DCHECK(call->arguments()->length() == 2);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
CHECK_ALIVE(VisitForValue(call->arguments()->at(1)));
HValue* index = Pop();
HValue* object = Pop();
HInstruction* result = New<HLoadKeyed>(
object, index, nullptr, nullptr, FAST_HOLEY_ELEMENTS, ALLOW_RETURN_HOLE);
return ast_context()->ReturnInstruction(result, call->id());
}
void HOptimizedGraphBuilder::GenerateFixedArraySet(CallRuntime* call) {
DCHECK(call->arguments()->length() == 3);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
CHECK_ALIVE(VisitForValue(call->arguments()->at(1)));
CHECK_ALIVE(VisitForValue(call->arguments()->at(2)));
HValue* value = Pop();
HValue* index = Pop();
HValue* object = Pop();
NoObservableSideEffectsScope no_effects(this);
Add<HStoreKeyed>(object, index, value, nullptr, FAST_HOLEY_ELEMENTS);
return ast_context()->ReturnValue(graph()->GetConstantUndefined());
}
void HOptimizedGraphBuilder::GenerateTheHole(CallRuntime* call) {
DCHECK(call->arguments()->length() == 0);
return ast_context()->ReturnValue(graph()->GetConstantHole());
}
void HOptimizedGraphBuilder::GenerateCreateIterResultObject(CallRuntime* call) {
DCHECK_EQ(2, call->arguments()->length());
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
CHECK_ALIVE(VisitForValue(call->arguments()->at(1)));
HValue* done = Pop();
HValue* value = Pop();
HValue* result = BuildCreateIterResultObject(value, done);
return ast_context()->ReturnValue(result);
}
void HOptimizedGraphBuilder::GenerateJSCollectionGetTable(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* receiver = Pop();
HInstruction* result = New<HLoadNamedField>(
receiver, nullptr, HObjectAccess::ForJSCollectionTable());
return ast_context()->ReturnInstruction(result, call->id());
}
void HOptimizedGraphBuilder::GenerateStringGetRawHashField(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* object = Pop();
HInstruction* result = New<HLoadNamedField>(
object, nullptr, HObjectAccess::ForStringHashField());
return ast_context()->ReturnInstruction(result, call->id());
}
template <typename CollectionType>
HValue* HOptimizedGraphBuilder::BuildAllocateOrderedHashTable() {
static const int kCapacity = CollectionType::kMinCapacity;
static const int kBucketCount = kCapacity / CollectionType::kLoadFactor;
static const int kFixedArrayLength = CollectionType::kHashTableStartIndex +
kBucketCount +
(kCapacity * CollectionType::kEntrySize);
static const int kSizeInBytes =
FixedArray::kHeaderSize + (kFixedArrayLength * kPointerSize);
// Allocate the table and add the proper map.
HValue* table =
Add<HAllocate>(Add<HConstant>(kSizeInBytes), HType::HeapObject(),
NOT_TENURED, FIXED_ARRAY_TYPE, graph()->GetConstant0());
AddStoreMapConstant(table, isolate()->factory()->ordered_hash_table_map());
// Initialize the FixedArray...
HValue* length = Add<HConstant>(kFixedArrayLength);
Add<HStoreNamedField>(table, HObjectAccess::ForFixedArrayLength(), length);
// ...and the OrderedHashTable fields.
Add<HStoreNamedField>(
table,
HObjectAccess::ForOrderedHashTableNumberOfBuckets<CollectionType>(),
Add<HConstant>(kBucketCount));
Add<HStoreNamedField>(
table,
HObjectAccess::ForOrderedHashTableNumberOfElements<CollectionType>(),
graph()->GetConstant0());
Add<HStoreNamedField>(
table, HObjectAccess::ForOrderedHashTableNumberOfDeletedElements<
CollectionType>(),
graph()->GetConstant0());
// Fill the buckets with kNotFound.
HValue* not_found = Add<HConstant>(CollectionType::kNotFound);
for (int i = 0; i < kBucketCount; ++i) {
Add<HStoreNamedField>(
table, HObjectAccess::ForOrderedHashTableBucket<CollectionType>(i),
not_found);
}
// Fill the data table with undefined.
HValue* undefined = graph()->GetConstantUndefined();
for (int i = 0; i < (kCapacity * CollectionType::kEntrySize); ++i) {
Add<HStoreNamedField>(table,
HObjectAccess::ForOrderedHashTableDataTableIndex<
CollectionType, kBucketCount>(i),
undefined);
}
return table;
}
void HOptimizedGraphBuilder::GenerateSetInitialize(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* receiver = Pop();
NoObservableSideEffectsScope no_effects(this);
HValue* table = BuildAllocateOrderedHashTable<OrderedHashSet>();
Add<HStoreNamedField>(receiver, HObjectAccess::ForJSCollectionTable(), table);
return ast_context()->ReturnValue(receiver);
}
void HOptimizedGraphBuilder::GenerateMapInitialize(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* receiver = Pop();
NoObservableSideEffectsScope no_effects(this);
HValue* table = BuildAllocateOrderedHashTable<OrderedHashMap>();
Add<HStoreNamedField>(receiver, HObjectAccess::ForJSCollectionTable(), table);
return ast_context()->ReturnValue(receiver);
}
template <typename CollectionType>
void HOptimizedGraphBuilder::BuildOrderedHashTableClear(HValue* receiver) {
HValue* old_table = Add<HLoadNamedField>(
receiver, nullptr, HObjectAccess::ForJSCollectionTable());
HValue* new_table = BuildAllocateOrderedHashTable<CollectionType>();
Add<HStoreNamedField>(
old_table, HObjectAccess::ForOrderedHashTableNextTable<CollectionType>(),
new_table);
Add<HStoreNamedField>(
old_table, HObjectAccess::ForOrderedHashTableNumberOfDeletedElements<
CollectionType>(),
Add<HConstant>(CollectionType::kClearedTableSentinel));
Add<HStoreNamedField>(receiver, HObjectAccess::ForJSCollectionTable(),
new_table);
}
void HOptimizedGraphBuilder::GenerateSetClear(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* receiver = Pop();
NoObservableSideEffectsScope no_effects(this);
BuildOrderedHashTableClear<OrderedHashSet>(receiver);
return ast_context()->ReturnValue(graph()->GetConstantUndefined());
}
void HOptimizedGraphBuilder::GenerateMapClear(CallRuntime* call) {
DCHECK(call->arguments()->length() == 1);
CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
HValue* receiver = Pop();
NoObservableSideEffectsScope no_effects(this);
BuildOrderedHashTableClear<OrderedHashMap>(receiver);
return ast_context()->ReturnValue(graph()->GetConstantUndefined());
}
void HOptimizedGraphBuilder::GenerateDebugBreakInOptimizedCode(
CallRuntime* call) {
Add<HDebugBreak>();
return ast_context()->ReturnValue(graph()->GetConstant0());
}
void HOptimizedGraphBuilder::GenerateDebugIsActive(CallRuntime* call) {
DCHECK(call->arguments()->length() == 0);
HValue* ref =
Add<HConstant>(ExternalReference::debug_is_active_address(isolate()));
HValue* value =
Add<HLoadNamedField>(ref, nullptr, HObjectAccess::ForExternalUInteger8());
return ast_context()->ReturnValue(value);
}
#undef CHECK_BAILOUT
#undef CHECK_ALIVE
HEnvironment::HEnvironment(HEnvironment* outer,
Scope* scope,
Handle<JSFunction> closure,
Zone* zone)
: closure_(closure),
values_(0, zone),
frame_type_(JS_FUNCTION),
parameter_count_(0),
specials_count_(1),
local_count_(0),
outer_(outer),
entry_(NULL),
pop_count_(0),
push_count_(0),
ast_id_(BailoutId::None()),
zone_(zone) {
DeclarationScope* declaration_scope = scope->GetDeclarationScope();
Initialize(declaration_scope->num_parameters() + 1,
declaration_scope->num_stack_slots(), 0);
}
HEnvironment::HEnvironment(Zone* zone, int parameter_count)
: values_(0, zone),
frame_type_(STUB),
parameter_count_(parameter_count),
specials_count_(1),
local_count_(0),
outer_(NULL),
entry_(NULL),
pop_count_(0),
push_count_(0),
ast_id_(BailoutId::None()),
zone_(zone) {
Initialize(parameter_count, 0, 0);
}
HEnvironment::HEnvironment(const HEnvironment* other, Zone* zone)
: values_(0, zone),
frame_type_(JS_FUNCTION),
parameter_count_(0),
specials_count_(0),
local_count_(0),
outer_(NULL),
entry_(NULL),
pop_count_(0),
push_count_(0),
ast_id_(other->ast_id()),
zone_(zone) {
Initialize(other);
}
HEnvironment::HEnvironment(HEnvironment* outer,
Handle<JSFunction> closure,
FrameType frame_type,
int arguments,
Zone* zone)
: closure_(closure),
values_(arguments, zone),
frame_type_(frame_type),
parameter_count_(arguments),
specials_count_(0),
local_count_(0),
outer_(outer),
entry_(NULL),
pop_count_(0),
push_count_(0),
ast_id_(BailoutId::None()),
zone_(zone) {
}
void HEnvironment::Initialize(int parameter_count,
int local_count,
int stack_height) {
parameter_count_ = parameter_count;
local_count_ = local_count;
// Avoid reallocating the temporaries' backing store on the first Push.
int total = parameter_count + specials_count_ + local_count + stack_height;
values_.Initialize(total + 4, zone());
for (int i = 0; i < total; ++i) values_.Add(NULL, zone());
}
void HEnvironment::Initialize(const HEnvironment* other) {
closure_ = other->closure();
values_.AddAll(other->values_, zone());
assigned_variables_.Union(other->assigned_variables_, zone());
frame_type_ = other->frame_type_;
parameter_count_ = other->parameter_count_;
local_count_ = other->local_count_;
if (other->outer_ != NULL) outer_ = other->outer_->Copy(); // Deep copy.
entry_ = other->entry_;
pop_count_ = other->pop_count_;
push_count_ = other->push_count_;
specials_count_ = other->specials_count_;
ast_id_ = other->ast_id_;
}
void HEnvironment::AddIncomingEdge(HBasicBlock* block, HEnvironment* other) {
DCHECK(!block->IsLoopHeader());
DCHECK(values_.length() == other->values_.length());
int length = values_.length();
for (int i = 0; i < length; ++i) {
HValue* value = values_[i];
if (value != NULL && value->IsPhi() && value->block() == block) {
// There is already a phi for the i'th value.
HPhi* phi = HPhi::cast(value);
// Assert index is correct and that we haven't missed an incoming edge.
DCHECK(phi->merged_index() == i || !phi->HasMergedIndex());
DCHECK(phi->OperandCount() == block->predecessors()->length());
phi->AddInput(other->values_[i]);
} else if (values_[i] != other->values_[i]) {
// There is a fresh value on the incoming edge, a phi is needed.
DCHECK(values_[i] != NULL && other->values_[i] != NULL);
HPhi* phi = block->AddNewPhi(i);
HValue* old_value = values_[i];
for (int j = 0; j < block->predecessors()->length(); j++) {
phi->AddInput(old_value);
}
phi->AddInput(other->values_[i]);
this->values_[i] = phi;
}
}
}
void HEnvironment::Bind(int index, HValue* value) {
DCHECK(value != NULL);
assigned_variables_.Add(index, zone());
values_[index] = value;
}
bool HEnvironment::HasExpressionAt(int index) const {
return index >= parameter_count_ + specials_count_ + local_count_;
}
bool HEnvironment::ExpressionStackIsEmpty() const {
DCHECK(length() >= first_expression_index());
return length() == first_expression_index();
}
void HEnvironment::SetExpressionStackAt(int index_from_top, HValue* value) {
int count = index_from_top + 1;
int index = values_.length() - count;
DCHECK(HasExpressionAt(index));
// The push count must include at least the element in question or else
// the new value will not be included in this environment's history.
if (push_count_ < count) {
// This is the same effect as popping then re-pushing 'count' elements.
pop_count_ += (count - push_count_);
push_count_ = count;
}
values_[index] = value;
}
HValue* HEnvironment::RemoveExpressionStackAt(int index_from_top) {
int count = index_from_top + 1;
int index = values_.length() - count;
DCHECK(HasExpressionAt(index));
// Simulate popping 'count' elements and then
// pushing 'count - 1' elements back.
pop_count_ += Max(count - push_count_, 0);
push_count_ = Max(push_count_ - count, 0) + (count - 1);
return values_.Remove(index);
}
void HEnvironment::Drop(int count) {
for (int i = 0; i < count; ++i) {
Pop();
}
}
void HEnvironment::Print() const {
OFStream os(stdout);
os << *this << "\n";
}
HEnvironment* HEnvironment::Copy() const {
return new(zone()) HEnvironment(this, zone());
}
HEnvironment* HEnvironment::CopyWithoutHistory() const {
HEnvironment* result = Copy();
result->ClearHistory();
return result;
}
HEnvironment* HEnvironment::CopyAsLoopHeader(HBasicBlock* loop_header) const {
HEnvironment* new_env = Copy();
for (int i = 0; i < values_.length(); ++i) {
HPhi* phi = loop_header->AddNewPhi(i);
phi->AddInput(values_[i]);
new_env->values_[i] = phi;
}
new_env->ClearHistory();
return new_env;
}
HEnvironment* HEnvironment::CreateStubEnvironment(HEnvironment* outer,
Handle<JSFunction> target,
FrameType frame_type,
int arguments) const {
HEnvironment* new_env =
new(zone()) HEnvironment(outer, target, frame_type,
arguments + 1, zone());
for (int i = 0; i <= arguments; ++i) { // Include receiver.
new_env->Push(ExpressionStackAt(arguments - i));
}
new_env->ClearHistory();
return new_env;
}
void HEnvironment::MarkAsTailCaller() {
DCHECK_EQ(JS_FUNCTION, frame_type());
frame_type_ = TAIL_CALLER_FUNCTION;
}
void HEnvironment::ClearTailCallerMark() {
DCHECK_EQ(TAIL_CALLER_FUNCTION, frame_type());
frame_type_ = JS_FUNCTION;
}
HEnvironment* HEnvironment::CopyForInlining(
Handle<JSFunction> target, int arguments, FunctionLiteral* function,
HConstant* undefined, InliningKind inlining_kind,
TailCallMode syntactic_tail_call_mode) const {
DCHECK_EQ(JS_FUNCTION, frame_type());
// Outer environment is a copy of this one without the arguments.
int arity = function->scope()->num_parameters();
HEnvironment* outer = Copy();
outer->Drop(arguments + 1); // Including receiver.
outer->ClearHistory();
if (syntactic_tail_call_mode == TailCallMode::kAllow) {
DCHECK_EQ(NORMAL_RETURN, inlining_kind);
outer->MarkAsTailCaller();
}
if (inlining_kind == CONSTRUCT_CALL_RETURN) {
// Create artificial constructor stub environment. The receiver should
// actually be the constructor function, but we pass the newly allocated
// object instead, DoComputeConstructStubFrame() relies on that.
outer = CreateStubEnvironment(outer, target, JS_CONSTRUCT, arguments);
} else if (inlining_kind == GETTER_CALL_RETURN) {
// We need an additional StackFrame::INTERNAL frame for restoring the
// correct context.
outer = CreateStubEnvironment(outer, target, JS_GETTER, arguments);
} else if (inlining_kind == SETTER_CALL_RETURN) {
// We need an additional StackFrame::INTERNAL frame for temporarily saving
// the argument of the setter, see StoreStubCompiler::CompileStoreViaSetter.
outer = CreateStubEnvironment(outer, target, JS_SETTER, arguments);
}
if (arity != arguments) {
// Create artificial arguments adaptation environment.
outer = CreateStubEnvironment(outer, target, ARGUMENTS_ADAPTOR, arguments);
}
HEnvironment* inner =
new(zone()) HEnvironment(outer, function->scope(), target, zone());
// Get the argument values from the original environment.
for (int i = 0; i <= arity; ++i) { // Include receiver.
HValue* push = (i <= arguments) ?
ExpressionStackAt(arguments - i) : undefined;
inner->SetValueAt(i, push);
}
inner->SetValueAt(arity + 1, context());
for (int i = arity + 2; i < inner->length(); ++i) {
inner->SetValueAt(i, undefined);
}
inner->set_ast_id(BailoutId::FunctionEntry());
return inner;
}
std::ostream& operator<<(std::ostream& os, const HEnvironment& env) {
for (int i = 0; i < env.length(); i++) {
if (i == 0) os << "parameters\n";
if (i == env.parameter_count()) os << "specials\n";
if (i == env.parameter_count() + env.specials_count()) os << "locals\n";
if (i == env.parameter_count() + env.specials_count() + env.local_count()) {
os << "expressions\n";
}
HValue* val = env.values()->at(i);
os << i << ": ";
if (val != NULL) {
os << val;
} else {
os << "NULL";
}
os << "\n";
}
return os << "\n";
}
void HTracer::TraceCompilation(CompilationInfo* info) {
Tag tag(this, "compilation");
std::string name;
if (info->parse_info()) {
Object* source_name = info->script()->name();
if (source_name->IsString()) {
String* str = String::cast(source_name);
if (str->length() > 0) {
name.append(str->ToCString().get());
name.append(":");
}
}
}
std::unique_ptr<char[]> method_name = info->GetDebugName();
name.append(method_name.get());
if (info->IsOptimizing()) {
PrintStringProperty("name", name.c_str());
PrintIndent();
trace_.Add("method \"%s:%d\"\n", method_name.get(),
info->optimization_id());
} else {
PrintStringProperty("name", name.c_str());
PrintStringProperty("method", "stub");
}
PrintLongProperty("date",
static_cast<int64_t>(base::OS::TimeCurrentMillis()));
}
void HTracer::TraceLithium(const char* name, LChunk* chunk) {
DCHECK(!chunk->isolate()->concurrent_recompilation_enabled());
AllowHandleDereference allow_deref;
AllowDeferredHandleDereference allow_deferred_deref;
Trace(name, chunk->graph(), chunk);
}
void HTracer::TraceHydrogen(const char* name, HGraph* graph) {
DCHECK(!graph->isolate()->concurrent_recompilation_enabled());
AllowHandleDereference allow_deref;
AllowDeferredHandleDereference allow_deferred_deref;
Trace(name, graph, NULL);
}
void HTracer::Trace(const char* name, HGraph* graph, LChunk* chunk) {
Tag tag(this, "cfg");
PrintStringProperty("name", name);
const ZoneList<HBasicBlock*>* blocks = graph->blocks();
for (int i = 0; i < blocks->length(); i++) {
HBasicBlock* current = blocks->at(i);
Tag block_tag(this, "block");
PrintBlockProperty("name", current->block_id());
PrintIntProperty("from_bci", -1);
PrintIntProperty("to_bci", -1);
if (!current->predecessors()->is_empty()) {
PrintIndent();
trace_.Add("predecessors");
for (int j = 0; j < current->predecessors()->length(); ++j) {
trace_.Add(" \"B%d\"", current->predecessors()->at(j)->block_id());
}
trace_.Add("\n");
} else {
PrintEmptyProperty("predecessors");
}
if (current->end()->SuccessorCount() == 0) {
PrintEmptyProperty("successors");
} else {
PrintIndent();
trace_.Add("successors");
for (HSuccessorIterator it(current->end()); !it.Done(); it.Advance()) {
trace_.Add(" \"B%d\"", it.Current()->block_id());
}
trace_.Add("\n");
}
PrintEmptyProperty("xhandlers");
{
PrintIndent();
trace_.Add("flags");
if (current->IsLoopSuccessorDominator()) {
trace_.Add(" \"dom-loop-succ\"");
}
if (current->IsUnreachable()) {
trace_.Add(" \"dead\"");
}
if (current->is_osr_entry()) {
trace_.Add(" \"osr\"");
}
trace_.Add("\n");
}
if (current->dominator() != NULL) {
PrintBlockProperty("dominator", current->dominator()->block_id());
}
PrintIntProperty("loop_depth", current->LoopNestingDepth());
if (chunk != NULL) {
int first_index = current->first_instruction_index();
int last_index = current->last_instruction_index();
PrintIntProperty(
"first_lir_id",
LifetimePosition::FromInstructionIndex(first_index).Value());
PrintIntProperty(
"last_lir_id",
LifetimePosition::FromInstructionIndex(last_index).Value());
}
{
Tag states_tag(this, "states");
Tag locals_tag(this, "locals");
int total = current->phis()->length();
PrintIntProperty("size", current->phis()->length());
PrintStringProperty("method", "None");
for (int j = 0; j < total; ++j) {
HPhi* phi = current->phis()->at(j);
PrintIndent();
std::ostringstream os;
os << phi->merged_index() << " " << NameOf(phi) << " " << *phi << "\n";
trace_.Add(os.str().c_str());
}
}
{
Tag HIR_tag(this, "HIR");
for (HInstructionIterator it(current); !it.Done(); it.Advance()) {
HInstruction* instruction = it.Current();
int uses = instruction->UseCount();
PrintIndent();
std::ostringstream os;
os << "0 " << uses << " " << NameOf(instruction) << " " << *instruction;
if (instruction->has_position()) {
const SourcePosition pos = instruction->position();
os << " pos:";
if (pos.isInlined()) os << "inlining(" << pos.InliningId() << "),";
os << pos.ScriptOffset();
}
os << " <|@\n";
trace_.Add(os.str().c_str());
}
}
if (chunk != NULL) {
Tag LIR_tag(this, "LIR");
int first_index = current->first_instruction_index();
int last_index = current->last_instruction_index();
if (first_index != -1 && last_index != -1) {
const ZoneList<LInstruction*>* instructions = chunk->instructions();
for (int i = first_index; i <= last_index; ++i) {
LInstruction* linstr = instructions->at(i);
if (linstr != NULL) {
PrintIndent();
trace_.Add("%d ",
LifetimePosition::FromInstructionIndex(i).Value());
linstr->PrintTo(&trace_);
std::ostringstream os;
os << " [hir:" << NameOf(linstr->hydrogen_value()) << "] <|@\n";
trace_.Add(os.str().c_str());
}
}
}
}
}
}
void HTracer::TraceLiveRanges(const char* name, LAllocator* allocator) {
Tag tag(this, "intervals");
PrintStringProperty("name", name);
const Vector<LiveRange*>* fixed_d = allocator->fixed_double_live_ranges();
for (int i = 0; i < fixed_d->length(); ++i) {
TraceLiveRange(fixed_d->at(i), "fixed", allocator->zone());
}
const Vector<LiveRange*>* fixed = allocator->fixed_live_ranges();
for (int i = 0; i < fixed->length(); ++i) {
TraceLiveRange(fixed->at(i), "fixed", allocator->zone());
}
const ZoneList<LiveRange*>* live_ranges = allocator->live_ranges();
for (int i = 0; i < live_ranges->length(); ++i) {
TraceLiveRange(live_ranges->at(i), "object", allocator->zone());
}
}
void HTracer::TraceLiveRange(LiveRange* range, const char* type,
Zone* zone) {
if (range != NULL && !range->IsEmpty()) {
PrintIndent();
trace_.Add("%d %s", range->id(), type);
if (range->HasRegisterAssigned()) {
LOperand* op = range->CreateAssignedOperand(zone);
int assigned_reg = op->index();
if (op->IsDoubleRegister()) {
trace_.Add(" \"%s\"",
GetRegConfig()->GetDoubleRegisterName(assigned_reg));
} else {
DCHECK(op->IsRegister());
trace_.Add(" \"%s\"",
GetRegConfig()->GetGeneralRegisterName(assigned_reg));
}
} else if (range->IsSpilled()) {
LOperand* op = range->TopLevel()->GetSpillOperand();
if (op->IsDoubleStackSlot()) {
trace_.Add(" \"double_stack:%d\"", op->index());
} else {
DCHECK(op->IsStackSlot());
trace_.Add(" \"stack:%d\"", op->index());
}
}
int parent_index = -1;
if (range->IsChild()) {
parent_index = range->parent()->id();
} else {
parent_index = range->id();
}
LOperand* op = range->FirstHint();
int hint_index = -1;
if (op != NULL && op->IsUnallocated()) {
hint_index = LUnallocated::cast(op)->virtual_register();
}
trace_.Add(" %d %d", parent_index, hint_index);
UseInterval* cur_interval = range->first_interval();
while (cur_interval != NULL && range->Covers(cur_interval->start())) {
trace_.Add(" [%d, %d[",
cur_interval->start().Value(),
cur_interval->end().Value());
cur_interval = cur_interval->next();
}
UsePosition* current_pos = range->first_pos();
while (current_pos != NULL) {
if (current_pos->RegisterIsBeneficial() || FLAG_trace_all_uses) {
trace_.Add(" %d M", current_pos->pos().Value());
}
current_pos = current_pos->next();
}
trace_.Add(" \"\"\n");
}
}
void HTracer::FlushToFile() {
AppendChars(filename_.start(), trace_.ToCString().get(), trace_.length(),
false);
trace_.Reset();
}
void HStatistics::Initialize(CompilationInfo* info) {
if (!info->has_shared_info()) return;
source_size_ += info->shared_info()->SourceSize();
}
void HStatistics::Print() {
PrintF(
"\n"
"----------------------------------------"
"----------------------------------------\n"
"--- Hydrogen timing results:\n"
"----------------------------------------"
"----------------------------------------\n");
base::TimeDelta sum;
for (int i = 0; i < times_.length(); ++i) {
sum += times_[i];
}
for (int i = 0; i < names_.length(); ++i) {
PrintF("%33s", names_[i]);
double ms = times_[i].InMillisecondsF();
double percent = times_[i].PercentOf(sum);
PrintF(" %8.3f ms / %4.1f %% ", ms, percent);
size_t size = sizes_[i];
double size_percent = static_cast<double>(size) * 100 / total_size_;
PrintF(" %9zu bytes / %4.1f %%\n", size, size_percent);
}
PrintF(
"----------------------------------------"
"----------------------------------------\n");
base::TimeDelta total = create_graph_ + optimize_graph_ + generate_code_;
PrintF("%33s %8.3f ms / %4.1f %% \n", "Create graph",
create_graph_.InMillisecondsF(), create_graph_.PercentOf(total));
PrintF("%33s %8.3f ms / %4.1f %% \n", "Optimize graph",
optimize_graph_.InMillisecondsF(), optimize_graph_.PercentOf(total));
PrintF("%33s %8.3f ms / %4.1f %% \n", "Generate and install code",
generate_code_.InMillisecondsF(), generate_code_.PercentOf(total));
PrintF(
"----------------------------------------"
"----------------------------------------\n");
PrintF("%33s %8.3f ms %9zu bytes\n", "Total",
total.InMillisecondsF(), total_size_);
PrintF("%33s (%.1f times slower than full code gen)\n", "",
total.TimesOf(full_code_gen_));
double source_size_in_kb = static_cast<double>(source_size_) / 1024;
double normalized_time = source_size_in_kb > 0
? total.InMillisecondsF() / source_size_in_kb
: 0;
double normalized_size_in_kb =
source_size_in_kb > 0
? static_cast<double>(total_size_) / 1024 / source_size_in_kb
: 0;
PrintF("%33s %8.3f ms %7.3f kB allocated\n",
"Average per kB source", normalized_time, normalized_size_in_kb);
}
void HStatistics::SaveTiming(const char* name, base::TimeDelta time,
size_t size) {
total_size_ += size;
for (int i = 0; i < names_.length(); ++i) {
if (strcmp(names_[i], name) == 0) {
times_[i] += time;
sizes_[i] += size;
return;
}
}
names_.Add(name);
times_.Add(time);
sizes_.Add(size);
}
HPhase::~HPhase() {
if (ShouldProduceTraceOutput()) {
isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
}
#ifdef DEBUG
graph_->Verify(false); // No full verify.
#endif
}
} // namespace internal
} // namespace v8