Google Git
Sign in
chromium / v8 / v8 / fa3cbf60d50466685964b36ff95b3599db5188a4 / . / src / arm / macro-assembler-arm.cc
blob: 3a2bb9462741d67d4992e0b86aa9fcaf3300e7a6 [file] [log] [blame]
// Copyright 2012 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 <limits.h> // For LONG_MIN, LONG_MAX.
#if V8_TARGET_ARCH_ARM
#include "src/assembler-inl.h"
#include "src/base/bits.h"
#include "src/base/division-by-constant.h"
#include "src/base/utils/random-number-generator.h"
#include "src/bootstrapper.h"
#include "src/callable.h"
#include "src/code-factory.h"
#include "src/counters.h"
#include "src/debug/debug.h"
#include "src/double.h"
#include "src/external-reference-table.h"
#include "src/frames-inl.h"
#include "src/macro-assembler.h"
#include "src/objects-inl.h"
#include "src/register-configuration.h"
#include "src/runtime/runtime.h"
#include "src/snapshot/embedded-data.h"
#include "src/snapshot/snapshot.h"
#include "src/wasm/wasm-code-manager.h"
// Satisfy cpplint check, but don't include platform-specific header. It is
// included recursively via macro-assembler.h.
#if 0
#include "src/arm/macro-assembler-arm.h"
#endif
namespace v8 {
namespace internal {
MacroAssembler::MacroAssembler(Isolate* isolate,
const AssemblerOptions& options, void* buffer,
int size, CodeObjectRequired create_code_object)
: TurboAssembler(isolate, options, buffer, size, create_code_object) {}
int TurboAssembler::RequiredStackSizeForCallerSaved(SaveFPRegsMode fp_mode,
Register exclusion1,
Register exclusion2,
Register exclusion3) const {
int bytes = 0;
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
bytes += NumRegs(list) * kPointerSize;
if (fp_mode == kSaveFPRegs) {
bytes += DwVfpRegister::NumRegisters() * DwVfpRegister::kSizeInBytes;
}
return bytes;
}
int TurboAssembler::PushCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1,
Register exclusion2, Register exclusion3) {
int bytes = 0;
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
stm(db_w, sp, list);
bytes += NumRegs(list) * kPointerSize;
if (fp_mode == kSaveFPRegs) {
SaveFPRegs(sp, lr);
bytes += DwVfpRegister::NumRegisters() * DwVfpRegister::kSizeInBytes;
}
return bytes;
}
int TurboAssembler::PopCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1,
Register exclusion2, Register exclusion3) {
int bytes = 0;
if (fp_mode == kSaveFPRegs) {
RestoreFPRegs(sp, lr);
bytes += DwVfpRegister::NumRegisters() * DwVfpRegister::kSizeInBytes;
}
RegList exclusions = 0;
if (exclusion1 != no_reg) {
exclusions |= exclusion1.bit();
if (exclusion2 != no_reg) {
exclusions |= exclusion2.bit();
if (exclusion3 != no_reg) {
exclusions |= exclusion3.bit();
}
}
}
RegList list = (kCallerSaved | lr.bit()) & ~exclusions;
ldm(ia_w, sp, list);
bytes += NumRegs(list) * kPointerSize;
return bytes;
}
void TurboAssembler::LoadFromConstantsTable(Register destination,
int constant_index) {
DCHECK(RootsTable::IsImmortalImmovable(RootIndex::kBuiltinsConstantsTable));
// The ldr call below could end up clobbering ip when the offset does not fit
// into 12 bits (and thus needs to be loaded from the constant pool). In that
// case, we need to be extra-careful and temporarily use another register as
// the target.
const uint32_t offset =
FixedArray::kHeaderSize + constant_index * kPointerSize - kHeapObjectTag;
const bool could_clobber_ip = !is_uint12(offset);
Register reg = destination;
if (could_clobber_ip) {
Push(r7);
reg = r7;
}
LoadRoot(reg, RootIndex::kBuiltinsConstantsTable);
ldr(destination, MemOperand(reg, offset));
if (could_clobber_ip) {
DCHECK_EQ(reg, r7);
Pop(r7);
}
}
void TurboAssembler::LoadRootRelative(Register destination, int32_t offset) {
ldr(destination, MemOperand(kRootRegister, offset));
}
void TurboAssembler::LoadRootRegisterOffset(Register destination,
intptr_t offset) {
if (offset == 0) {
Move(destination, kRootRegister);
} else {
add(destination, kRootRegister, Operand(offset));
}
}
void TurboAssembler::Jump(Register target, Condition cond) { bx(target, cond); }
void TurboAssembler::Jump(intptr_t target, RelocInfo::Mode rmode,
Condition cond) {
mov(pc, Operand(target, rmode), LeaveCC, cond);
}
void TurboAssembler::Jump(Address target, RelocInfo::Mode rmode,
Condition cond) {
DCHECK(!RelocInfo::IsCodeTarget(rmode));
Jump(static_cast<intptr_t>(target), rmode, cond);
}
void TurboAssembler::Jump(Handle<Code> code, RelocInfo::Mode rmode,
Condition cond) {
DCHECK(RelocInfo::IsCodeTarget(rmode));
if (FLAG_embedded_builtins) {
int builtin_index = Builtins::kNoBuiltinId;
bool target_is_isolate_independent_builtin =
isolate()->builtins()->IsBuiltinHandle(code, &builtin_index) &&
Builtins::IsIsolateIndependent(builtin_index);
if (target_is_isolate_independent_builtin &&
options().use_pc_relative_calls_and_jumps) {
int32_t code_target_index = AddCodeTarget(code);
b(code_target_index * kInstrSize, cond, RelocInfo::RELATIVE_CODE_TARGET);
return;
} else if (root_array_available_ && options().isolate_independent_code) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
IndirectLoadConstant(scratch, code);
add(scratch, scratch, Operand(Code::kHeaderSize - kHeapObjectTag));
Jump(scratch, cond);
return;
} else if (target_is_isolate_independent_builtin &&
options().inline_offheap_trampolines) {
// Inline the trampoline.
RecordCommentForOffHeapTrampoline(builtin_index);
EmbeddedData d = EmbeddedData::FromBlob();
Address entry = d.InstructionStartOfBuiltin(builtin_index);
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
mov(ip, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Jump(ip, cond);
return;
}
}
// 'code' is always generated ARM code, never THUMB code
Jump(static_cast<intptr_t>(code.address()), rmode, cond);
}
void TurboAssembler::Call(Register target, Condition cond) {
// Block constant pool for the call instruction sequence.
BlockConstPoolScope block_const_pool(this);
blx(target, cond);
}
void TurboAssembler::Call(Address target, RelocInfo::Mode rmode, Condition cond,
TargetAddressStorageMode mode,
bool check_constant_pool) {
// Check if we have to emit the constant pool before we block it.
if (check_constant_pool) MaybeCheckConstPool();
// Block constant pool for the call instruction sequence.
BlockConstPoolScope block_const_pool(this);
bool old_predictable_code_size = predictable_code_size();
if (mode == NEVER_INLINE_TARGET_ADDRESS) {
set_predictable_code_size(true);
}
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
// Call sequence on V7 or later may be :
// movw ip, #... @ call address low 16
// movt ip, #... @ call address high 16
// blx ip
// @ return address
// Or for pre-V7 or values that may be back-patched
// to avoid ICache flushes:
// ldr ip, [pc, #...] @ call address
// blx ip
// @ return address
mov(ip, Operand(target, rmode));
blx(ip, cond);
if (mode == NEVER_INLINE_TARGET_ADDRESS) {
set_predictable_code_size(old_predictable_code_size);
}
}
void TurboAssembler::Call(Handle<Code> code, RelocInfo::Mode rmode,
Condition cond, TargetAddressStorageMode mode,
bool check_constant_pool) {
DCHECK(RelocInfo::IsCodeTarget(rmode));
if (FLAG_embedded_builtins) {
int builtin_index = Builtins::kNoBuiltinId;
bool target_is_isolate_independent_builtin =
isolate()->builtins()->IsBuiltinHandle(code, &builtin_index) &&
Builtins::IsIsolateIndependent(builtin_index);
if (target_is_isolate_independent_builtin &&
options().use_pc_relative_calls_and_jumps) {
int32_t code_target_index = AddCodeTarget(code);
bl(code_target_index * kInstrSize, cond, RelocInfo::RELATIVE_CODE_TARGET);
return;
} else if (root_array_available_ && options().isolate_independent_code) {
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
IndirectLoadConstant(ip, code);
add(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
Call(ip, cond);
return;
} else if (target_is_isolate_independent_builtin &&
options().inline_offheap_trampolines) {
// Inline the trampoline.
RecordCommentForOffHeapTrampoline(builtin_index);
EmbeddedData d = EmbeddedData::FromBlob();
Address entry = d.InstructionStartOfBuiltin(builtin_index);
// Use ip directly instead of using UseScratchRegisterScope, as we do not
// preserve scratch registers across calls.
mov(ip, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Call(ip, cond);
return;
}
}
// 'code' is always generated ARM code, never THUMB code
Call(code.address(), rmode, cond, mode);
}
void TurboAssembler::CallBuiltinPointer(Register builtin_pointer) {
STATIC_ASSERT(kSystemPointerSize == 4);
STATIC_ASSERT(kSmiShiftSize == 0);
STATIC_ASSERT(kSmiTagSize == 1);
STATIC_ASSERT(kSmiTag == 0);
// The builtin_pointer register contains the builtin index as a Smi.
// Untagging is folded into the indexing operand below.
mov(builtin_pointer,
Operand(builtin_pointer, LSL, kSystemPointerSizeLog2 - kSmiTagSize));
add(builtin_pointer, builtin_pointer,
Operand(IsolateData::builtin_entry_table_offset()));
ldr(builtin_pointer, MemOperand(kRootRegister, builtin_pointer));
Call(builtin_pointer);
}
void TurboAssembler::StoreReturnAddressAndCall(Register target) {
// This generates the final instruction sequence for calls to C functions
// once an exit frame has been constructed.
//
// Note that this assumes the caller code (i.e. the Code object currently
// being generated) is immovable or that the callee function cannot trigger
// GC, since the callee function will return to it.
// Compute the return address in lr to return to after the jump below. The pc
// is already at '+ 8' from the current instruction; but return is after three
// instructions, so add another 4 to pc to get the return address.
Assembler::BlockConstPoolScope block_const_pool(this);
add(lr, pc, Operand(4));
str(lr, MemOperand(sp));
Call(target);
}
void TurboAssembler::Ret(Condition cond) { bx(lr, cond); }
void TurboAssembler::Drop(int count, Condition cond) {
if (count > 0) {
add(sp, sp, Operand(count * kPointerSize), LeaveCC, cond);
}
}
void TurboAssembler::Drop(Register count, Condition cond) {
add(sp, sp, Operand(count, LSL, kPointerSizeLog2), LeaveCC, cond);
}
void TurboAssembler::Ret(int drop, Condition cond) {
Drop(drop, cond);
Ret(cond);
}
void TurboAssembler::Call(Label* target) { bl(target); }
void TurboAssembler::Push(Handle<HeapObject> handle) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(handle));
push(scratch);
}
void TurboAssembler::Push(Smi smi) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(smi));
push(scratch);
}
void TurboAssembler::Move(Register dst, Smi smi) { mov(dst, Operand(smi)); }
void TurboAssembler::Move(Register dst, Handle<HeapObject> value) {
if (FLAG_embedded_builtins) {
if (root_array_available_ && options().isolate_independent_code) {
IndirectLoadConstant(dst, value);
return;
}
}
mov(dst, Operand(value));
}
void TurboAssembler::Move(Register dst, ExternalReference reference) {
if (FLAG_embedded_builtins) {
if (root_array_available_ && options().isolate_independent_code) {
IndirectLoadExternalReference(dst, reference);
return;
}
}
mov(dst, Operand(reference));
}
void TurboAssembler::Move(Register dst, Register src, Condition cond) {
if (dst != src) {
mov(dst, src, LeaveCC, cond);
}
}
void TurboAssembler::Move(SwVfpRegister dst, SwVfpRegister src,
Condition cond) {
if (dst != src) {
vmov(dst, src, cond);
}
}
void TurboAssembler::Move(DwVfpRegister dst, DwVfpRegister src,
Condition cond) {
if (dst != src) {
vmov(dst, src, cond);
}
}
void TurboAssembler::Move(QwNeonRegister dst, QwNeonRegister src) {
if (dst != src) {
vmov(dst, src);
}
}
void TurboAssembler::Swap(Register srcdst0, Register srcdst1) {
DCHECK(srcdst0 != srcdst1);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, srcdst0);
mov(srcdst0, srcdst1);
mov(srcdst1, scratch);
}
void TurboAssembler::Swap(DwVfpRegister srcdst0, DwVfpRegister srcdst1) {
DCHECK(srcdst0 != srcdst1);
DCHECK(VfpRegisterIsAvailable(srcdst0));
DCHECK(VfpRegisterIsAvailable(srcdst1));
if (CpuFeatures::IsSupported(NEON)) {
vswp(srcdst0, srcdst1);
} else {
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = temps.AcquireD();
vmov(scratch, srcdst0);
vmov(srcdst0, srcdst1);
vmov(srcdst1, scratch);
}
}
void TurboAssembler::Swap(QwNeonRegister srcdst0, QwNeonRegister srcdst1) {
DCHECK(srcdst0 != srcdst1);
vswp(srcdst0, srcdst1);
}
void MacroAssembler::Mls(Register dst, Register src1, Register src2,
Register srcA, Condition cond) {
if (CpuFeatures::IsSupported(ARMv7)) {
CpuFeatureScope scope(this, ARMv7);
mls(dst, src1, src2, srcA, cond);
} else {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(srcA != scratch);
mul(scratch, src1, src2, LeaveCC, cond);
sub(dst, srcA, scratch, LeaveCC, cond);
}
}
void MacroAssembler::And(Register dst, Register src1, const Operand& src2,
Condition cond) {
if (!src2.IsRegister() && !src2.MustOutputRelocInfo(this) &&
src2.immediate() == 0) {
mov(dst, Operand::Zero(), LeaveCC, cond);
} else if (!(src2.InstructionsRequired(this) == 1) &&
!src2.MustOutputRelocInfo(this) &&
CpuFeatures::IsSupported(ARMv7) &&
base::bits::IsPowerOfTwo(src2.immediate() + 1)) {
CpuFeatureScope scope(this, ARMv7);
ubfx(dst, src1, 0,
WhichPowerOf2(static_cast<uint32_t>(src2.immediate()) + 1), cond);
} else {
and_(dst, src1, src2, LeaveCC, cond);
}
}
void MacroAssembler::Ubfx(Register dst, Register src1, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
and_(dst, src1, Operand(mask), LeaveCC, cond);
if (lsb != 0) {
mov(dst, Operand(dst, LSR, lsb), LeaveCC, cond);
}
} else {
CpuFeatureScope scope(this, ARMv7);
ubfx(dst, src1, lsb, width, cond);
}
}
void MacroAssembler::Sbfx(Register dst, Register src1, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
and_(dst, src1, Operand(mask), LeaveCC, cond);
int shift_up = 32 - lsb - width;
int shift_down = lsb + shift_up;
if (shift_up != 0) {
mov(dst, Operand(dst, LSL, shift_up), LeaveCC, cond);
}
if (shift_down != 0) {
mov(dst, Operand(dst, ASR, shift_down), LeaveCC, cond);
}
} else {
CpuFeatureScope scope(this, ARMv7);
sbfx(dst, src1, lsb, width, cond);
}
}
void TurboAssembler::Bfc(Register dst, Register src, int lsb, int width,
Condition cond) {
DCHECK_LT(lsb, 32);
if (!CpuFeatures::IsSupported(ARMv7) || predictable_code_size()) {
int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
bic(dst, src, Operand(mask));
} else {
CpuFeatureScope scope(this, ARMv7);
Move(dst, src, cond);
bfc(dst, lsb, width, cond);
}
}
void MacroAssembler::Load(Register dst,
const MemOperand& src,
Representation r) {
DCHECK(!r.IsDouble());
if (r.IsInteger8()) {
ldrsb(dst, src);
} else if (r.IsUInteger8()) {
ldrb(dst, src);
} else if (r.IsInteger16()) {
ldrsh(dst, src);
} else if (r.IsUInteger16()) {
ldrh(dst, src);
} else {
ldr(dst, src);
}
}
void MacroAssembler::Store(Register src,
const MemOperand& dst,
Representation r) {
DCHECK(!r.IsDouble());
if (r.IsInteger8() || r.IsUInteger8()) {
strb(src, dst);
} else if (r.IsInteger16() || r.IsUInteger16()) {
strh(src, dst);
} else {
if (r.IsHeapObject()) {
AssertNotSmi(src);
} else if (r.IsSmi()) {
AssertSmi(src);
}
str(src, dst);
}
}
void TurboAssembler::LoadRoot(Register destination, RootIndex index,
Condition cond) {
ldr(destination,
MemOperand(kRootRegister, RootRegisterOffsetForRootIndex(index)), cond);
}
void MacroAssembler::RecordWriteField(Register object, int offset,
Register value, Register dst,
LinkRegisterStatus lr_status,
SaveFPRegsMode save_fp,
RememberedSetAction remembered_set_action,
SmiCheck smi_check) {
// First, check if a write barrier is even needed. The tests below
// catch stores of Smis.
Label done;
// Skip barrier if writing a smi.
if (smi_check == INLINE_SMI_CHECK) {
JumpIfSmi(value, &done);
}
// Although the object register is tagged, the offset is relative to the start
// of the object, so so offset must be a multiple of kPointerSize.
DCHECK(IsAligned(offset, kPointerSize));
add(dst, object, Operand(offset - kHeapObjectTag));
if (emit_debug_code()) {
Label ok;
tst(dst, Operand(kPointerSize - 1));
b(eq, &ok);
stop("Unaligned cell in write barrier");
bind(&ok);
}
RecordWrite(object, dst, value, lr_status, save_fp, remembered_set_action,
OMIT_SMI_CHECK);
bind(&done);
// Clobber clobbered input registers when running with the debug-code flag
// turned on to provoke errors.
if (emit_debug_code()) {
mov(value, Operand(bit_cast<int32_t>(kZapValue + 4)));
mov(dst, Operand(bit_cast<int32_t>(kZapValue + 8)));
}
}
void TurboAssembler::SaveRegisters(RegList registers) {
DCHECK_GT(NumRegs(registers), 0);
RegList regs = 0;
for (int i = 0; i < Register::kNumRegisters; ++i) {
if ((registers >> i) & 1u) {
regs |= Register::from_code(i).bit();
}
}
stm(db_w, sp, regs);
}
void TurboAssembler::RestoreRegisters(RegList registers) {
DCHECK_GT(NumRegs(registers), 0);
RegList regs = 0;
for (int i = 0; i < Register::kNumRegisters; ++i) {
if ((registers >> i) & 1u) {
regs |= Register::from_code(i).bit();
}
}
ldm(ia_w, sp, regs);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Register address,
RememberedSetAction remembered_set_action, SaveFPRegsMode fp_mode) {
CallRecordWriteStub(
object, address, remembered_set_action, fp_mode,
isolate()->builtins()->builtin_handle(Builtins::kRecordWrite),
kNullAddress);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Register address,
RememberedSetAction remembered_set_action, SaveFPRegsMode fp_mode,
Address wasm_target) {
CallRecordWriteStub(object, address, remembered_set_action, fp_mode,
Handle<Code>::null(), wasm_target);
}
void TurboAssembler::CallRecordWriteStub(
Register object, Register address,
RememberedSetAction remembered_set_action, SaveFPRegsMode fp_mode,
Handle<Code> code_target, Address wasm_target) {
DCHECK_NE(code_target.is_null(), wasm_target == kNullAddress);
// TODO(albertnetymk): For now we ignore remembered_set_action and fp_mode,
// i.e. always emit remember set and save FP registers in RecordWriteStub. If
// large performance regression is observed, we should use these values to
// avoid unnecessary work.
RecordWriteDescriptor descriptor;
RegList registers = descriptor.allocatable_registers();
SaveRegisters(registers);
Register object_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kObject));
Register slot_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kSlot));
Register remembered_set_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kRememberedSet));
Register fp_mode_parameter(
descriptor.GetRegisterParameter(RecordWriteDescriptor::kFPMode));
Push(object);
Push(address);
Pop(slot_parameter);
Pop(object_parameter);
Move(remembered_set_parameter, Smi::FromEnum(remembered_set_action));
Move(fp_mode_parameter, Smi::FromEnum(fp_mode));
if (code_target.is_null()) {
Call(wasm_target, RelocInfo::WASM_STUB_CALL);
} else {
Call(code_target, RelocInfo::CODE_TARGET);
}
RestoreRegisters(registers);
}
// Will clobber 3 registers: object, address, and value. The register 'object'
// contains a heap object pointer. The heap object tag is shifted away.
// A scratch register also needs to be available.
void MacroAssembler::RecordWrite(Register object, Register address,
Register value, LinkRegisterStatus lr_status,
SaveFPRegsMode fp_mode,
RememberedSetAction remembered_set_action,
SmiCheck smi_check) {
DCHECK(object != value);
if (emit_debug_code()) {
{
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
ldr(scratch, MemOperand(address));
cmp(scratch, value);
}
Check(eq, AbortReason::kWrongAddressOrValuePassedToRecordWrite);
}
if (remembered_set_action == OMIT_REMEMBERED_SET &&
!FLAG_incremental_marking) {
return;
}
// First, check if a write barrier is even needed. The tests below
// catch stores of smis and stores into the young generation.
Label done;
if (smi_check == INLINE_SMI_CHECK) {
JumpIfSmi(value, &done);
}
CheckPageFlag(value,
value, // Used as scratch.
MemoryChunk::kPointersToHereAreInterestingMask, eq, &done);
CheckPageFlag(object,
value, // Used as scratch.
MemoryChunk::kPointersFromHereAreInterestingMask,
eq,
&done);
// Record the actual write.
if (lr_status == kLRHasNotBeenSaved) {
push(lr);
}
CallRecordWriteStub(object, address, remembered_set_action, fp_mode);
if (lr_status == kLRHasNotBeenSaved) {
pop(lr);
}
bind(&done);
// Count number of write barriers in generated code.
isolate()->counters()->write_barriers_static()->Increment();
{
UseScratchRegisterScope temps(this);
IncrementCounter(isolate()->counters()->write_barriers_dynamic(), 1,
temps.Acquire(), value);
}
// Clobber clobbered registers when running with the debug-code flag
// turned on to provoke errors.
if (emit_debug_code()) {
mov(address, Operand(bit_cast<int32_t>(kZapValue + 12)));
mov(value, Operand(bit_cast<int32_t>(kZapValue + 16)));
}
}
void TurboAssembler::PushCommonFrame(Register marker_reg) {
if (marker_reg.is_valid()) {
if (marker_reg.code() > fp.code()) {
stm(db_w, sp, fp.bit() | lr.bit());
mov(fp, Operand(sp));
Push(marker_reg);
} else {
stm(db_w, sp, marker_reg.bit() | fp.bit() | lr.bit());
add(fp, sp, Operand(kPointerSize));
}
} else {
stm(db_w, sp, fp.bit() | lr.bit());
mov(fp, sp);
}
}
void TurboAssembler::PushStandardFrame(Register function_reg) {
DCHECK(!function_reg.is_valid() || function_reg.code() < cp.code());
stm(db_w, sp, (function_reg.is_valid() ? function_reg.bit() : 0) | cp.bit() |
fp.bit() | lr.bit());
int offset = -StandardFrameConstants::kContextOffset;
offset += function_reg.is_valid() ? kPointerSize : 0;
add(fp, sp, Operand(offset));
}
// Push and pop all registers that can hold pointers.
void MacroAssembler::PushSafepointRegisters() {
// Safepoints expect a block of contiguous register values starting with r0.
DCHECK_EQ(kSafepointSavedRegisters, (1 << kNumSafepointSavedRegisters) - 1);
// Safepoints expect a block of kNumSafepointRegisters values on the
// stack, so adjust the stack for unsaved registers.
const int num_unsaved = kNumSafepointRegisters - kNumSafepointSavedRegisters;
DCHECK_GE(num_unsaved, 0);
sub(sp, sp, Operand(num_unsaved * kPointerSize));
stm(db_w, sp, kSafepointSavedRegisters);
}
void MacroAssembler::PopSafepointRegisters() {
const int num_unsaved = kNumSafepointRegisters - kNumSafepointSavedRegisters;
ldm(ia_w, sp, kSafepointSavedRegisters);
add(sp, sp, Operand(num_unsaved * kPointerSize));
}
int MacroAssembler::SafepointRegisterStackIndex(int reg_code) {
// The registers are pushed starting with the highest encoding,
// which means that lowest encodings are closest to the stack pointer.
DCHECK(reg_code >= 0 && reg_code < kNumSafepointRegisters);
return reg_code;
}
void TurboAssembler::VFPCanonicalizeNaN(const DwVfpRegister dst,
const DwVfpRegister src,
const Condition cond) {
// Subtracting 0.0 preserves all inputs except for signalling NaNs, which
// become quiet NaNs. We use vsub rather than vadd because vsub preserves -0.0
// inputs: -0.0 + 0.0 = 0.0, but -0.0 - 0.0 = -0.0.
vsub(dst, src, kDoubleRegZero, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const SwVfpRegister src1,
const SwVfpRegister src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const SwVfpRegister src1,
const float src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const DwVfpRegister src1,
const DwVfpRegister src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndSetFlags(const DwVfpRegister src1,
const double src2,
const Condition cond) {
// Compare and move FPSCR flags to the normal condition flags.
VFPCompareAndLoadFlags(src1, src2, pc, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const SwVfpRegister src1,
const SwVfpRegister src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const SwVfpRegister src1,
const float src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const DwVfpRegister src1,
const DwVfpRegister src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VFPCompareAndLoadFlags(const DwVfpRegister src1,
const double src2,
const Register fpscr_flags,
const Condition cond) {
// Compare and load FPSCR.
vcmp(src1, src2, cond);
vmrs(fpscr_flags, cond);
}
void TurboAssembler::VmovHigh(Register dst, DwVfpRegister src) {
if (src.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(src.code());
vmov(dst, loc.high());
} else {
vmov(NeonS32, dst, src, 1);
}
}
void TurboAssembler::VmovHigh(DwVfpRegister dst, Register src) {
if (dst.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(dst.code());
vmov(loc.high(), src);
} else {
vmov(NeonS32, dst, 1, src);
}
}
void TurboAssembler::VmovLow(Register dst, DwVfpRegister src) {
if (src.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(src.code());
vmov(dst, loc.low());
} else {
vmov(NeonS32, dst, src, 0);
}
}
void TurboAssembler::VmovLow(DwVfpRegister dst, Register src) {
if (dst.code() < 16) {
const LowDwVfpRegister loc = LowDwVfpRegister::from_code(dst.code());
vmov(loc.low(), src);
} else {
vmov(NeonS32, dst, 0, src);
}
}
void TurboAssembler::VmovExtended(Register dst, int src_code) {
DCHECK_LE(SwVfpRegister::kNumRegisters, src_code);
DCHECK_GT(SwVfpRegister::kNumRegisters * 2, src_code);
if (src_code & 0x1) {
VmovHigh(dst, DwVfpRegister::from_code(src_code / 2));
} else {
VmovLow(dst, DwVfpRegister::from_code(src_code / 2));
}
}
void TurboAssembler::VmovExtended(int dst_code, Register src) {
DCHECK_LE(SwVfpRegister::kNumRegisters, dst_code);
DCHECK_GT(SwVfpRegister::kNumRegisters * 2, dst_code);
if (dst_code & 0x1) {
VmovHigh(DwVfpRegister::from_code(dst_code / 2), src);
} else {
VmovLow(DwVfpRegister::from_code(dst_code / 2), src);
}
}
void TurboAssembler::VmovExtended(int dst_code, int src_code) {
if (src_code == dst_code) return;
if (src_code < SwVfpRegister::kNumRegisters &&
dst_code < SwVfpRegister::kNumRegisters) {
// src and dst are both s-registers.
vmov(SwVfpRegister::from_code(dst_code),
SwVfpRegister::from_code(src_code));
return;
}
DwVfpRegister dst_d_reg = DwVfpRegister::from_code(dst_code / 2);
DwVfpRegister src_d_reg = DwVfpRegister::from_code(src_code / 2);
int dst_offset = dst_code & 1;
int src_offset = src_code & 1;
if (CpuFeatures::IsSupported(NEON)) {
UseScratchRegisterScope temps(this);
DwVfpRegister scratch = temps.AcquireD();
// On Neon we can shift and insert from d-registers.
if (src_offset == dst_offset) {
// Offsets are the same, use vdup to copy the source to the opposite lane.
vdup(Neon32, scratch, src_d_reg, src_offset);
// Here we are extending the lifetime of scratch.
src_d_reg = scratch;
src_offset = dst_offset ^ 1;
}
if (dst_offset) {
if (dst_d_reg == src_d_reg) {
vdup(Neon32, dst_d_reg, src_d_reg, 0);
} else {
vsli(Neon64, dst_d_reg, src_d_reg, 32);
}
} else {
if (dst_d_reg == src_d_reg) {
vdup(Neon32, dst_d_reg, src_d_reg, 1);
} else {
vsri(Neon64, dst_d_reg, src_d_reg, 32);
}
}
return;
}
// Without Neon, use the scratch registers to move src and/or dst into
// s-registers.
UseScratchRegisterScope temps(this);
LowDwVfpRegister d_scratch = temps.AcquireLowD();
LowDwVfpRegister d_scratch2 = temps.AcquireLowD();
int s_scratch_code = d_scratch.low().code();
int s_scratch_code2 = d_scratch2.low().code();
if (src_code < SwVfpRegister::kNumRegisters) {
// src is an s-register, dst is not.
vmov(d_scratch, dst_d_reg);
vmov(SwVfpRegister::from_code(s_scratch_code + dst_offset),
SwVfpRegister::from_code(src_code));
vmov(dst_d_reg, d_scratch);
} else if (dst_code < SwVfpRegister::kNumRegisters) {
// dst is an s-register, src is not.
vmov(d_scratch, src_d_reg);
vmov(SwVfpRegister::from_code(dst_code),
SwVfpRegister::from_code(s_scratch_code + src_offset));
} else {
// Neither src or dst are s-registers. Both scratch double registers are
// available when there are 32 VFP registers.
vmov(d_scratch, src_d_reg);
vmov(d_scratch2, dst_d_reg);
vmov(SwVfpRegister::from_code(s_scratch_code + dst_offset),
SwVfpRegister::from_code(s_scratch_code2 + src_offset));
vmov(dst_d_reg, d_scratch2);
}
}
void TurboAssembler::VmovExtended(int dst_code, const MemOperand& src) {
if (dst_code < SwVfpRegister::kNumRegisters) {
vldr(SwVfpRegister::from_code(dst_code), src);
} else {
UseScratchRegisterScope temps(this);
LowDwVfpRegister scratch = temps.AcquireLowD();
// TODO(bbudge) If Neon supported, use load single lane form of vld1.
int dst_s_code = scratch.low().code() + (dst_code & 1);
vmov(scratch, DwVfpRegister::from_code(dst_code / 2));
vldr(SwVfpRegister::from_code(dst_s_code), src);
vmov(DwVfpRegister::from_code(dst_code / 2), scratch);
}
}
void TurboAssembler::VmovExtended(const MemOperand& dst, int src_code) {
if (src_code < SwVfpRegister::kNumRegisters) {
vstr(SwVfpRegister::from_code(src_code), dst);
} else {
// TODO(bbudge) If Neon supported, use store single lane form of vst1.
UseScratchRegisterScope temps(this);
LowDwVfpRegister scratch = temps.AcquireLowD();
int src_s_code = scratch.low().code() + (src_code & 1);
vmov(scratch, DwVfpRegister::from_code(src_code / 2));
vstr(SwVfpRegister::from_code(src_s_code), dst);
}
}
void TurboAssembler::ExtractLane(Register dst, QwNeonRegister src,
NeonDataType dt, int lane) {
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_word = byte >> kDoubleSizeLog2;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
DwVfpRegister double_source =
DwVfpRegister::from_code(src.code() * 2 + double_word);
vmov(dt, dst, double_source, double_lane);
}
void TurboAssembler::ExtractLane(Register dst, DwVfpRegister src,
NeonDataType dt, int lane) {
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
vmov(dt, dst, src, double_lane);
}
void TurboAssembler::ExtractLane(SwVfpRegister dst, QwNeonRegister src,
int lane) {
int s_code = src.code() * 4 + lane;
VmovExtended(dst.code(), s_code);
}
void TurboAssembler::ReplaceLane(QwNeonRegister dst, QwNeonRegister src,
Register src_lane, NeonDataType dt, int lane) {
Move(dst, src);
int size = NeonSz(dt); // 0, 1, 2
int byte = lane << size;
int double_word = byte >> kDoubleSizeLog2;
int double_byte = byte & (kDoubleSize - 1);
int double_lane = double_byte >> size;
DwVfpRegister double_dst =
DwVfpRegister::from_code(dst.code() * 2 + double_word);
vmov(dt, double_dst, double_lane, src_lane);
}
void TurboAssembler::ReplaceLane(QwNeonRegister dst, QwNeonRegister src,
SwVfpRegister src_lane, int lane) {
Move(dst, src);
int s_code = dst.code() * 4 + lane;
VmovExtended(s_code, src_lane.code());
}
void TurboAssembler::LslPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_high, src_low));
DCHECK(!AreAliased(dst_high, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
lsl(dst_high, src_low, Operand(scratch));
mov(dst_low, Operand(0));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsl(dst_high, src_high, Operand(shift));
orr(dst_high, dst_high, Operand(src_low, LSR, scratch));
lsl(dst_low, src_low, Operand(shift));
bind(&done);
}
void TurboAssembler::LslPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK(!AreAliased(dst_high, src_low));
Label less_than_32;
Label done;
if (shift == 0) {
Move(dst_high, src_high);
Move(dst_low, src_low);
} else if (shift == 32) {
Move(dst_high, src_low);
Move(dst_low, Operand(0));
} else if (shift >= 32) {
shift &= 0x1F;
lsl(dst_high, src_low, Operand(shift));
mov(dst_low, Operand(0));
} else {
lsl(dst_high, src_high, Operand(shift));
orr(dst_high, dst_high, Operand(src_low, LSR, 32 - shift));
lsl(dst_low, src_low, Operand(shift));
}
}
void TurboAssembler::LsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_low, src_high));
DCHECK(!AreAliased(dst_low, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
lsr(dst_low, src_high, Operand(scratch));
mov(dst_high, Operand(0));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, scratch));
lsr(dst_high, src_high, Operand(shift));
bind(&done);
}
void TurboAssembler::LsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK(!AreAliased(dst_low, src_high));
Label less_than_32;
Label done;
if (shift == 32) {
mov(dst_low, src_high);
mov(dst_high, Operand(0));
} else if (shift > 32) {
shift &= 0x1F;
lsr(dst_low, src_high, Operand(shift));
mov(dst_high, Operand(0));
} else if (shift == 0) {
Move(dst_low, src_low);
Move(dst_high, src_high);
} else {
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, 32 - shift));
lsr(dst_high, src_high, Operand(shift));
}
}
void TurboAssembler::AsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
Register shift) {
DCHECK(!AreAliased(dst_low, src_high));
DCHECK(!AreAliased(dst_low, shift));
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Label less_than_32;
Label done;
rsb(scratch, shift, Operand(32), SetCC);
b(gt, &less_than_32);
// If shift >= 32
and_(scratch, shift, Operand(0x1F));
asr(dst_low, src_high, Operand(scratch));
asr(dst_high, src_high, Operand(31));
jmp(&done);
bind(&less_than_32);
// If shift < 32
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, scratch));
asr(dst_high, src_high, Operand(shift));
bind(&done);
}
void TurboAssembler::AsrPair(Register dst_low, Register dst_high,
Register src_low, Register src_high,
uint32_t shift) {
DCHECK(!AreAliased(dst_low, src_high));
Label less_than_32;
Label done;
if (shift == 32) {
mov(dst_low, src_high);
asr(dst_high, src_high, Operand(31));
} else if (shift > 32) {
shift &= 0x1F;
asr(dst_low, src_high, Operand(shift));
asr(dst_high, src_high, Operand(31));
} else if (shift == 0) {
Move(dst_low, src_low);
Move(dst_high, src_high);
} else {
lsr(dst_low, src_low, Operand(shift));
orr(dst_low, dst_low, Operand(src_high, LSL, 32 - shift));
asr(dst_high, src_high, Operand(shift));
}
}
void TurboAssembler::StubPrologue(StackFrame::Type type) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(StackFrame::TypeToMarker(type)));
PushCommonFrame(scratch);
}
void TurboAssembler::Prologue() { PushStandardFrame(r1); }
void TurboAssembler::EnterFrame(StackFrame::Type type,
bool load_constant_pool_pointer_reg) {
// r0-r3: preserved
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
mov(scratch, Operand(StackFrame::TypeToMarker(type)));
PushCommonFrame(scratch);
}
int TurboAssembler::LeaveFrame(StackFrame::Type type) {
// r0: preserved
// r1: preserved
// r2: preserved
// Drop the execution stack down to the frame pointer and restore
// the caller frame pointer and return address.
mov(sp, fp);
int frame_ends = pc_offset();
ldm(ia_w, sp, fp.bit() | lr.bit());
return frame_ends;
}
void MacroAssembler::EnterExitFrame(bool save_doubles, int stack_space,
StackFrame::Type frame_type) {
DCHECK(frame_type == StackFrame::EXIT ||
frame_type == StackFrame::BUILTIN_EXIT);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
// Set up the frame structure on the stack.
DCHECK_EQ(2 * kPointerSize, ExitFrameConstants::kCallerSPDisplacement);
DCHECK_EQ(1 * kPointerSize, ExitFrameConstants::kCallerPCOffset);
DCHECK_EQ(0 * kPointerSize, ExitFrameConstants::kCallerFPOffset);
mov(scratch, Operand(StackFrame::TypeToMarker(frame_type)));
PushCommonFrame(scratch);
// Reserve room for saved entry sp and code object.
sub(sp, fp, Operand(ExitFrameConstants::kFixedFrameSizeFromFp));
if (emit_debug_code()) {
mov(scratch, Operand::Zero());
str(scratch, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
Move(scratch, CodeObject());
str(scratch, MemOperand(fp, ExitFrameConstants::kCodeOffset));
// Save the frame pointer and the context in top.
Move(scratch, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
str(fp, MemOperand(scratch));
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
str(cp, MemOperand(scratch));
// Optionally save all double registers.
if (save_doubles) {
SaveFPRegs(sp, scratch);
// Note that d0 will be accessible at
// fp - ExitFrameConstants::kFrameSize -
// DwVfpRegister::kNumRegisters * kDoubleSize,
// since the sp slot and code slot were pushed after the fp.
}
// Reserve place for the return address and stack space and align the frame
// preparing for calling the runtime function.
const int frame_alignment = MacroAssembler::ActivationFrameAlignment();
sub(sp, sp, Operand((stack_space + 1) * kPointerSize));
if (frame_alignment > 0) {
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
and_(sp, sp, Operand(-frame_alignment));
}
// Set the exit frame sp value to point just before the return address
// location.
add(scratch, sp, Operand(kPointerSize));
str(scratch, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
int TurboAssembler::ActivationFrameAlignment() {
#if V8_HOST_ARCH_ARM
// Running on the real platform. Use the alignment as mandated by the local
// environment.
// Note: This will break if we ever start generating snapshots on one ARM
// platform for another ARM platform with a different alignment.
return base::OS::ActivationFrameAlignment();
#else // V8_HOST_ARCH_ARM
// If we are using the simulator then we should always align to the expected
// alignment. As the simulator is used to generate snapshots we do not know
// if the target platform will need alignment, so this is controlled from a
// flag.
return FLAG_sim_stack_alignment;
#endif // V8_HOST_ARCH_ARM
}
void MacroAssembler::LeaveExitFrame(bool save_doubles, Register argument_count,
bool argument_count_is_length) {
ConstantPoolUnavailableScope constant_pool_unavailable(this);
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
// Optionally restore all double registers.
if (save_doubles) {
// Calculate the stack location of the saved doubles and restore them.
const int offset = ExitFrameConstants::kFixedFrameSizeFromFp;
sub(r3, fp, Operand(offset + DwVfpRegister::kNumRegisters * kDoubleSize));
RestoreFPRegs(r3, scratch);
}
// Clear top frame.
mov(r3, Operand::Zero());
Move(scratch, ExternalReference::Create(IsolateAddressId::kCEntryFPAddress,
isolate()));
str(r3, MemOperand(scratch));
// Restore current context from top and clear it in debug mode.
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
ldr(cp, MemOperand(scratch));
#ifdef DEBUG
mov(r3, Operand(Context::kInvalidContext));
Move(scratch,
ExternalReference::Create(IsolateAddressId::kContextAddress, isolate()));
str(r3, MemOperand(scratch));
#endif
// Tear down the exit frame, pop the arguments, and return.
mov(sp, Operand(fp));
ldm(ia_w, sp, fp.bit() | lr.bit());
if (argument_count.is_valid()) {
if (argument_count_is_length) {
add(sp, sp, argument_count);
} else {
add(sp, sp, Operand(argument_count, LSL, kPointerSizeLog2));
}
}
}
void TurboAssembler::MovFromFloatResult(const DwVfpRegister dst) {
if (use_eabi_hardfloat()) {
Move(dst, d0);
} else {
vmov(dst, r0, r1);
}
}
// On ARM this is just a synonym to make the purpose clear.
void TurboAssembler::MovFromFloatParameter(DwVfpRegister dst) {
MovFromFloatResult(dst);
}
void TurboAssembler::PrepareForTailCall(const ParameterCount& callee_args_count,
Register caller_args_count_reg,
Register scratch0, Register scratch1) {
#if DEBUG
if (callee_args_count.is_reg()) {
DCHECK(!AreAliased(callee_args_count.reg(), caller_args_count_reg, scratch0,
scratch1));
} else {
DCHECK(!AreAliased(caller_args_count_reg, scratch0, scratch1));
}
#endif
// Calculate the end of destination area where we will put the arguments
// after we drop current frame. We add kPointerSize to count the receiver
// argument which is not included into formal parameters count.
Register dst_reg = scratch0;
add(dst_reg, fp, Operand(caller_args_count_reg, LSL, kPointerSizeLog2));
add(dst_reg, dst_reg,
Operand(StandardFrameConstants::kCallerSPOffset + kPointerSize));
Register src_reg = caller_args_count_reg;
// Calculate the end of source area. +kPointerSize is for the receiver.
if (callee_args_count.is_reg()) {
add(src_reg, sp, Operand(callee_args_count.reg(), LSL, kPointerSizeLog2));
add(src_reg, src_reg, Operand(kPointerSize));
} else {
add(src_reg, sp,
Operand((callee_args_count.immediate() + 1) * kPointerSize));
}
if (FLAG_debug_code) {
cmp(src_reg, dst_reg);
Check(lo, AbortReason::kStackAccessBelowStackPointer);
}
// Restore caller's frame pointer and return address now as they will be
// overwritten by the copying loop.
ldr(lr, MemOperand(fp, StandardFrameConstants::kCallerPCOffset));
ldr(fp, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
// Now copy callee arguments to the caller frame going backwards to avoid
// callee arguments corruption (source and destination areas could overlap).
// Both src_reg and dst_reg are pointing to the word after the one to copy,
// so they must be pre-decremented in the loop.
Register tmp_reg = scratch1;
Label loop, entry;
b(&entry);
bind(&loop);
ldr(tmp_reg, MemOperand(src_reg, -kPointerSize, PreIndex));
str(tmp_reg, MemOperand(dst_reg, -kPointerSize, PreIndex));
bind(&entry);
cmp(sp, src_reg);
b(ne, &loop);
// Leave current frame.
mov(sp, dst_reg);
}
void MacroAssembler::InvokePrologue(const ParameterCount& expected,
const ParameterCount& actual, Label* done,
bool* definitely_mismatches,
InvokeFlag flag) {
bool definitely_matches = false;
*definitely_mismatches = false;
Label regular_invoke;
// Check whether the expected and actual arguments count match. If not,
// setup registers according to contract with ArgumentsAdaptorTrampoline:
// r0: actual arguments count
// r1: function (passed through to callee)
// r2: expected arguments count
// The code below is made a lot easier because the calling code already sets
// up actual and expected registers according to the contract if values are
// passed in registers.
DCHECK(actual.is_immediate() || actual.reg() == r0);
DCHECK(expected.is_immediate() || expected.reg() == r2);
if (expected.is_immediate()) {
DCHECK(actual.is_immediate());
mov(r0, Operand(actual.immediate()));
if (expected.immediate() == actual.immediate()) {
definitely_matches = true;
} else {
const int sentinel = SharedFunctionInfo::kDontAdaptArgumentsSentinel;
if (expected.immediate() == sentinel) {
// Don't worry about adapting arguments for builtins that
// don't want that done. Skip adaption code by making it look
// like we have a match between expected and actual number of
// arguments.
definitely_matches = true;
} else {
*definitely_mismatches = true;
mov(r2, Operand(expected.immediate()));
}
}
} else {
if (actual.is_immediate()) {
mov(r0, Operand(actual.immediate()));
cmp(expected.reg(), Operand(actual.immediate()));
b(eq, &regular_invoke);
} else {
cmp(expected.reg(), Operand(actual.reg()));
b(eq, &regular_invoke);
}
}
if (!definitely_matches) {
Handle<Code> adaptor = BUILTIN_CODE(isolate(), ArgumentsAdaptorTrampoline);
if (flag == CALL_FUNCTION) {
Call(adaptor);
if (!*definitely_mismatches) {
b(done);
}
} else {
Jump(adaptor, RelocInfo::CODE_TARGET);
}
bind(&regular_invoke);
}
}
void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
const ParameterCount& expected,
const ParameterCount& actual) {
Label skip_hook;
ExternalReference debug_hook_active =
ExternalReference::debug_hook_on_function_call_address(isolate());
Move(r4, debug_hook_active);
ldrsb(r4, MemOperand(r4));
cmp(r4, Operand(0));
b(eq, &skip_hook);
{
// Load receiver to pass it later to DebugOnFunctionCall hook.
if (actual.is_reg()) {
mov(r4, actual.reg());
} else {
mov(r4, Operand(actual.immediate()));
}
ldr(r4, MemOperand(sp, r4, LSL, kPointerSizeLog2));
FrameScope frame(this,
has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
if (expected.is_reg()) {
SmiTag(expected.reg());
Push(expected.reg());
}
if (actual.is_reg()) {
SmiTag(actual.reg());
Push(actual.reg());
}
if (new_target.is_valid()) {
Push(new_target);
}
Push(fun);
Push(fun);
Push(r4);
CallRuntime(Runtime::kDebugOnFunctionCall);
Pop(fun);
if (new_target.is_valid()) {
Pop(new_target);
}
if (actual.is_reg()) {
Pop(actual.reg());
SmiUntag(actual.reg());
}
if (expected.is_reg()) {
Pop(expected.reg());
SmiUntag(expected.reg());
}
}
bind(&skip_hook);
}
void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
const ParameterCount& expected,
const ParameterCount& actual,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK(flag == JUMP_FUNCTION || has_frame());
DCHECK(function == r1);
DCHECK_IMPLIES(new_target.is_valid(), new_target == r3);
// On function call, call into the debugger if necessary.
CheckDebugHook(function, new_target, expected, actual);
// Clear the new.target register if not given.
if (!new_target.is_valid()) {
LoadRoot(r3, RootIndex::kUndefinedValue);
}
Label done;
bool definitely_mismatches = false;
InvokePrologue(expected, actual, &done, &definitely_mismatches, flag);
if (!definitely_mismatches) {
// We call indirectly through the code field in the function to
// allow recompilation to take effect without changing any of the
// call sites.
Register code = kJavaScriptCallCodeStartRegister;
ldr(code, FieldMemOperand(function, JSFunction::kCodeOffset));
add(code, code, Operand(Code::kHeaderSize - kHeapObjectTag));
if (flag == CALL_FUNCTION) {
Call(code);
} else {
DCHECK(flag == JUMP_FUNCTION);
Jump(code);
}
// Continue here if InvokePrologue does handle the invocation due to
// mismatched parameter counts.
bind(&done);
}
}
void MacroAssembler::InvokeFunction(Register fun, Register new_target,
const ParameterCount& actual,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK(flag == JUMP_FUNCTION || has_frame());
// Contract with called JS functions requires that function is passed in r1.
DCHECK(fun == r1);
Register expected_reg = r2;
Register temp_reg = r4;
ldr(temp_reg, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
ldrh(expected_reg,
FieldMemOperand(temp_reg,
SharedFunctionInfo::kFormalParameterCountOffset));
ParameterCount expected(expected_reg);
InvokeFunctionCode(fun, new_target, expected, actual, flag);
}
void MacroAssembler::InvokeFunction(Register function,
const ParameterCount& expected,
const ParameterCount& actual,
InvokeFlag flag) {
// You can't call a function without a valid frame.
DCHECK(flag == JUMP_FUNCTION || has_frame());
// Contract with called JS functions requires that function is passed in r1.
DCHECK(function == r1);
// Get the function and setup the context.
ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
InvokeFunctionCode(r1, no_reg, expected, actual, flag);
}
void MacroAssembler::MaybeDropFrames() {
// Check whether we need to drop frames to restart a function on the stack.
ExternalReference restart_fp =
ExternalReference::debug_restart_fp_address(isolate());
Move(r1, restart_fp);
ldr(r1, MemOperand(r1));
tst(r1, r1);
Jump(BUILTIN_CODE(isolate(), FrameDropperTrampoline), RelocInfo::CODE_TARGET,
ne);
}
void MacroAssembler::PushStackHandler() {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 2 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
Push(Smi::zero()); // Padding.
// Link the current handler as the next handler.
Move(r6,
ExternalReference::Create(IsolateAddressId::kHandlerAddress, isolate()));
ldr(r5, MemOperand(r6));
push(r5);
// Set this new handler as the current one.
str(sp, MemOperand(r6));
}
void MacroAssembler::PopStackHandler() {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
pop(r1);
Move(scratch,
ExternalReference::Create(IsolateAddressId::kHandlerAddress, isolate()));
str(r1, MemOperand(scratch));
add(sp, sp, Operand(StackHandlerConstants::kSize - kPointerSize));
}
void MacroAssembler::CompareObjectType(Register object,
Register map,
Register type_reg,
InstanceType type) {
UseScratchRegisterScope temps(this);
const Register temp = type_reg == no_reg ? temps.Acquire() : type_reg;
ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
CompareInstanceType(map, temp, type);
}
void MacroAssembler::CompareInstanceType(Register map,
Register type_reg,
InstanceType type) {
ldrh(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
cmp(type_reg, Operand(type));
}
void MacroAssembler::CompareRoot(Register obj, RootIndex index) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
DCHECK(obj != scratch);
LoadRoot(scratch, index);
cmp(obj, scratch);
}
void MacroAssembler::TryDoubleToInt32Exact(Register result,
DwVfpRegister double_input,
LowDwVfpRegister double_scratch) {
DCHECK(double_input != double_scratch);
vcvt_s32_f64(double_scratch.low(), double_input);
vmov(result, double_scratch.low());
vcvt_f64_s32(double_scratch, double_scratch.low());
VFPCompareAndSetFlags(double_input, double_scratch);
}
void TurboAssembler::TryInlineTruncateDoubleToI(Register result,
DwVfpRegister double_input,
Label* done) {
UseScratchRegisterScope temps(this);
SwVfpRegister single_scratch = SwVfpRegister::no_reg();
if (temps.CanAcquireVfp<SwVfpRegister>()) {
single_scratch = temps.AcquireS();
} else {
// Re-use the input as a scratch register. However, we can only do this if
// the input register is d0-d15 as there are no s32+ registers.
DCHECK_LT(double_input.code(), LowDwVfpRegister::kNumRegisters);
LowDwVfpRegister double_scratch =
LowDwVfpRegister::from_code(double_input.code());
single_scratch = double_scratch.low();
}
vcvt_s32_f64(single_scratch, double_input);
vmov(result, single_scratch);
Register scratch = temps.Acquire();
// If result is not saturated (0x7FFFFFFF or 0x80000000), we are done.
sub(scratch, result, Operand(1));
cmp(scratch, Operand(0x7FFFFFFE));
b(lt, done);
}
void TurboAssembler::TruncateDoubleToI(Isolate* isolate, Zone* zone,
Register result,
DwVfpRegister double_input,
StubCallMode stub_mode) {
Label done;
TryInlineTruncateDoubleToI(result, double_input, &done);
// If we fell through then inline version didn't succeed - call stub instead.
push(lr);
sub(sp, sp, Operand(kDoubleSize)); // Put input on stack.
vstr(double_input, MemOperand(sp, 0));
if (stub_mode == StubCallMode::kCallWasmRuntimeStub) {
Call(wasm::WasmCode::kDoubleToI, RelocInfo::WASM_STUB_CALL);
} else {
Call(BUILTIN_CODE(isolate, DoubleToI), RelocInfo::CODE_TARGET);
}
ldr(result, MemOperand(sp, 0));
add(sp, sp, Operand(kDoubleSize));
pop(lr);
bind(&done);
}
void TurboAssembler::CallRuntimeWithCEntry(Runtime::FunctionId fid,
Register centry) {
const Runtime::Function* f = Runtime::FunctionForId(fid);
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
mov(r0, Operand(f->nargs));
Move(r1, ExternalReference::Create(f));
DCHECK(!AreAliased(centry, r0, r1));
add(centry, centry, Operand(Code::kHeaderSize - kHeapObjectTag));
Call(centry);
}
void MacroAssembler::CallRuntime(const Runtime::Function* f,
int num_arguments,
SaveFPRegsMode save_doubles) {
// All parameters are on the stack. r0 has the return value after call.
// If the expected number of arguments of the runtime function is
// constant, we check that the actual number of arguments match the
// expectation.
CHECK(f->nargs < 0 || f->nargs == num_arguments);
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
mov(r0, Operand(num_arguments));
Move(r1, ExternalReference::Create(f));
Handle<Code> code =
CodeFactory::CEntry(isolate(), f->result_size, save_doubles);
Call(code, RelocInfo::CODE_TARGET);
}
void MacroAssembler::TailCallRuntime(Runtime::FunctionId fid) {
const Runtime::Function* function = Runtime::FunctionForId(fid);
DCHECK_EQ(1, function->result_size);
if (function->nargs >= 0) {
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
mov(r0, Operand(function->nargs));
}
JumpToExternalReference(ExternalReference::Create(fid));
}
void MacroAssembler::JumpToExternalReference(const ExternalReference& builtin,
bool builtin_exit_frame) {
#if defined(__thumb__)
// Thumb mode builtin.
DCHECK_EQ(builtin.address() & 1, 1);
#endif
Move(r1, builtin);
Handle<Code> code = CodeFactory::CEntry(isolate(), 1, kDontSaveFPRegs,
kArgvOnStack, builtin_exit_frame);
Jump(code, RelocInfo::CODE_TARGET);
}
void MacroAssembler::JumpToInstructionStream(Address entry) {
mov(kOffHeapTrampolineRegister, Operand(entry, RelocInfo::OFF_HEAP_TARGET));
Jump(kOffHeapTrampolineRegister);
}
void MacroAssembler::LoadWeakValue(Register out, Register in,
Label* target_if_cleared) {
cmp(in, Operand(kClearedWeakHeapObjectLower32));
b(eq, target_if_cleared);
and_(out, in, Operand(~kWeakHeapObjectMask));
}
void MacroAssembler::IncrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
DCHECK_GT(value, 0);
if (FLAG_native_code_counters && counter->Enabled()) {
Move(scratch2, ExternalReference::Create(counter));
ldr(scratch1, MemOperand(scratch2));
add(scratch1, scratch1, Operand(value));
str(scratch1, MemOperand(scratch2));
}
}
void MacroAssembler::DecrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
DCHECK_GT(value, 0);
if (FLAG_native_code_counters && counter->Enabled()) {
Move(scratch2, ExternalReference::Create(counter));
ldr(scratch1, MemOperand(scratch2));
sub(scratch1, scratch1, Operand(value));
str(scratch1, MemOperand(scratch2));
}
}
void TurboAssembler::Assert(Condition cond, AbortReason reason) {
if (emit_debug_code())
Check(cond, reason);
}
void TurboAssembler::AssertUnreachable(AbortReason reason) {
if (emit_debug_code()) Abort(reason);
}
void TurboAssembler::Check(Condition cond, AbortReason reason) {
Label L;
b(cond, &L);
Abort(reason);
// will not return here
bind(&L);
}
void TurboAssembler::Abort(AbortReason reason) {
Label abort_start;
bind(&abort_start);
const char* msg = GetAbortReason(reason);
#ifdef DEBUG
RecordComment("Abort message: ");
RecordComment(msg);
#endif
// Avoid emitting call to builtin if requested.
if (trap_on_abort()) {
stop(msg);
return;
}
if (should_abort_hard()) {
// We don't care if we constructed a frame. Just pretend we did.
FrameScope assume_frame(this, StackFrame::NONE);
Move32BitImmediate(r0, Operand(static_cast<int>(reason)));
PrepareCallCFunction(1, 0, r1);
Move(r1, ExternalReference::abort_with_reason());
// Use Call directly to avoid any unneeded overhead. The function won't
// return anyway.
Call(r1);
return;
}
Move(r1, Smi::FromInt(static_cast<int>(reason)));
// Disable stub call restrictions to always allow calls to abort.
if (!has_frame()) {
// We don't actually want to generate a pile of code for this, so just
// claim there is a stack frame, without generating one.
FrameScope scope(this, StackFrame::NONE);
Call(BUILTIN_CODE(isolate(), Abort), RelocInfo::CODE_TARGET);
} else {
Call(BUILTIN_CODE(isolate(), Abort), RelocInfo::CODE_TARGET);
}
// will not return here
}
void MacroAssembler::LoadGlobalProxy(Register dst) {
LoadNativeContextSlot(Context::GLOBAL_PROXY_INDEX, dst);
}
void MacroAssembler::LoadNativeContextSlot(int index, Register dst) {
ldr(dst, NativeContextMemOperand());
ldr(dst, ContextMemOperand(dst, index));
}
void TurboAssembler::InitializeRootRegister() {
ExternalReference isolate_root = ExternalReference::isolate_root(isolate());
mov(kRootRegister, Operand(isolate_root));
}
void MacroAssembler::SmiTag(Register reg, SBit s) {
add(reg, reg, Operand(reg), s);
}
void MacroAssembler::SmiTag(Register dst, Register src, SBit s) {
add(dst, src, Operand(src), s);
}
void MacroAssembler::UntagAndJumpIfSmi(
Register dst, Register src, Label* smi_case) {
STATIC_ASSERT(kSmiTag == 0);
SmiUntag(dst, src, SetCC);
b(cc, smi_case); // Shifter carry is not set for a smi.
}
void MacroAssembler::SmiTst(Register value) {
tst(value, Operand(kSmiTagMask));
}
void TurboAssembler::JumpIfSmi(Register value, Label* smi_label) {
tst(value, Operand(kSmiTagMask));
b(eq, smi_label);
}
void TurboAssembler::JumpIfEqual(Register x, int32_t y, Label* dest) {
cmp(x, Operand(y));
b(eq, dest);
}
void TurboAssembler::JumpIfLessThan(Register x, int32_t y, Label* dest) {
cmp(x, Operand(y));
b(lt, dest);
}
void MacroAssembler::JumpIfNotSmi(Register value, Label* not_smi_label) {
tst(value, Operand(kSmiTagMask));
b(ne, not_smi_label);
}
void MacroAssembler::JumpIfEitherSmi(Register reg1,
Register reg2,
Label* on_either_smi) {
STATIC_ASSERT(kSmiTag == 0);
tst(reg1, Operand(kSmiTagMask));
tst(reg2, Operand(kSmiTagMask), ne);
b(eq, on_either_smi);
}
void MacroAssembler::AssertNotSmi(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmi);
}
}
void MacroAssembler::AssertSmi(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(eq, AbortReason::kOperandIsNotASmi);
}
}
void MacroAssembler::AssertConstructor(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAConstructor);
push(object);
ldr(object, FieldMemOperand(object, HeapObject::kMapOffset));
ldrb(object, FieldMemOperand(object, Map::kBitFieldOffset));
tst(object, Operand(Map::IsConstructorBit::kMask));
pop(object);
Check(ne, AbortReason::kOperandIsNotAConstructor);
}
}
void MacroAssembler::AssertFunction(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAFunction);
push(object);
CompareObjectType(object, object, object, JS_FUNCTION_TYPE);
pop(object);
Check(eq, AbortReason::kOperandIsNotAFunction);
}
}
void MacroAssembler::AssertBoundFunction(Register object) {
if (emit_debug_code()) {
STATIC_ASSERT(kSmiTag == 0);
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotABoundFunction);
push(object);
CompareObjectType(object, object, object, JS_BOUND_FUNCTION_TYPE);
pop(object);
Check(eq, AbortReason::kOperandIsNotABoundFunction);
}
}
void MacroAssembler::AssertGeneratorObject(Register object) {
if (!emit_debug_code()) return;
tst(object, Operand(kSmiTagMask));
Check(ne, AbortReason::kOperandIsASmiAndNotAGeneratorObject);
// Load map
Register map = object;
push(object);
ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
// Check if JSGeneratorObject
Label do_check;
Register instance_type = object;
CompareInstanceType(map, instance_type, JS_GENERATOR_OBJECT_TYPE);
b(eq, &do_check);
// Check if JSAsyncFunctionObject (See MacroAssembler::CompareInstanceType)
cmp(instance_type, Operand(JS_ASYNC_FUNCTION_OBJECT_TYPE));
b(eq, &do_check);
// Check if JSAsyncGeneratorObject (See MacroAssembler::CompareInstanceType)
cmp(instance_type, Operand(JS_ASYNC_GENERATOR_OBJECT_TYPE));
bind(&do_check);
// Restore generator object to register and perform assertion
pop(object);
Check(eq, AbortReason::kOperandIsNotAGeneratorObject);
}
void MacroAssembler::AssertUndefinedOrAllocationSite(Register object,
Register scratch) {
if (emit_debug_code()) {
Label done_checking;
AssertNotSmi(object);
CompareRoot(object, RootIndex::kUndefinedValue);
b(eq, &done_checking);
ldr(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
CompareInstanceType(scratch, scratch, ALLOCATION_SITE_TYPE);
Assert(eq, AbortReason::kExpectedUndefinedOrCell);
bind(&done_checking);
}
}
void TurboAssembler::CheckFor32DRegs(Register scratch) {
Move(scratch, ExternalReference::cpu_features());
ldr(scratch, MemOperand(scratch));
tst(scratch, Operand(1u << VFP32DREGS));
}
void TurboAssembler::SaveFPRegs(Register location, Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vstm(db_w, location, d16, d31, ne);
sub(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
vstm(db_w, location, d0, d15);
}
void TurboAssembler::RestoreFPRegs(Register location, Register scratch) {
CpuFeatureScope scope(this, VFP32DREGS, CpuFeatureScope::kDontCheckSupported);
CheckFor32DRegs(scratch);
vldm(ia_w, location, d0, d15);
vldm(ia_w, location, d16, d31, ne);
add(location, location, Operand(16 * kDoubleSize), LeaveCC, eq);
}
template <typename T>
void TurboAssembler::FloatMaxHelper(T result, T left, T right,
Label* out_of_line) {
// This trivial case is caught sooner, so that the out-of-line code can be
// completely avoided.
DCHECK(left != right);
if (CpuFeatures::IsSupported(ARMv8)) {
CpuFeatureScope scope(this, ARMv8);
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
vmaxnm(result, left, right);
} else {
Label done;
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
// Avoid a conditional instruction if the result register is unique.
bool aliased_result_reg = result == left || result == right;
Move(result, right, aliased_result_reg ? mi : al);
Move(result, left, gt);
b(ne, &done);
// Left and right are equal, but check for +/-0.
VFPCompareAndSetFlags(left, 0.0);
b(eq, out_of_line);
// The arguments are equal and not zero, so it doesn't matter which input we
// pick. We have already moved one input into the result (if it didn't
// already alias) so there's nothing more to do.
bind(&done);
}
}
template <typename T>
void TurboAssembler::FloatMaxOutOfLineHelper(T result, T left, T right) {
DCHECK(left != right);
// ARMv8: At least one of left and right is a NaN.
// Anything else: At least one of left and right is a NaN, or both left and
// right are zeroes with unknown sign.
// If left and right are +/-0, select the one with the most positive sign.
// If left or right are NaN, vadd propagates the appropriate one.
vadd(result, left, right);
}
template <typename T>
void TurboAssembler::FloatMinHelper(T result, T left, T right,
Label* out_of_line) {
// This trivial case is caught sooner, so that the out-of-line code can be
// completely avoided.
DCHECK(left != right);
if (CpuFeatures::IsSupported(ARMv8)) {
CpuFeatureScope scope(this, ARMv8);
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
vminnm(result, left, right);
} else {
Label done;
VFPCompareAndSetFlags(left, right);
b(vs, out_of_line);
// Avoid a conditional instruction if the result register is unique.
bool aliased_result_reg = result == left || result == right;
Move(result, left, aliased_result_reg ? mi : al);
Move(result, right, gt);
b(ne, &done);
// Left and right are equal, but check for +/-0.
VFPCompareAndSetFlags(left, 0.0);
// If the arguments are equal and not zero, it doesn't matter which input we
// pick. We have already moved one input into the result (if it didn't
// already alias) so there's nothing more to do.
b(ne, &done);
// At this point, both left and right are either 0 or -0.
// We could use a single 'vorr' instruction here if we had NEON support.
// The algorithm used is -((-L) + (-R)), which is most efficiently expressed
// as -((-L) - R).
if (left == result) {
DCHECK(right != result);
vneg(result, left);
vsub(result, result, right);
vneg(result, result);
} else {
DCHECK(left != result);
vneg(result, right);
vsub(result, result, left);
vneg(result, result);
}
bind(&done);
}
}
template <typename T>
void TurboAssembler::FloatMinOutOfLineHelper(T result, T left, T right) {
DCHECK(left != right);
// At least one of left and right is a NaN. Use vadd to propagate the NaN
// appropriately. +/-0 is handled inline.
vadd(result, left, right);
}
void TurboAssembler::FloatMax(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right, Label* out_of_line) {
FloatMaxHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMin(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right, Label* out_of_line) {
FloatMinHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMax(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right, Label* out_of_line) {
FloatMaxHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMin(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right, Label* out_of_line) {
FloatMinHelper(result, left, right, out_of_line);
}
void TurboAssembler::FloatMaxOutOfLine(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right) {
FloatMaxOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMinOutOfLine(SwVfpRegister result, SwVfpRegister left,
SwVfpRegister right) {
FloatMinOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMaxOutOfLine(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right) {
FloatMaxOutOfLineHelper(result, left, right);
}
void TurboAssembler::FloatMinOutOfLine(DwVfpRegister result, DwVfpRegister left,
DwVfpRegister right) {
FloatMinOutOfLineHelper(result, left, right);
}
static const int kRegisterPassedArguments = 4;
int TurboAssembler::CalculateStackPassedWords(int num_reg_arguments,
int num_double_arguments) {
int stack_passed_words = 0;
if (use_eabi_hardfloat()) {
// In the hard floating point calling convention, we can use
// all double registers to pass doubles.
if (num_double_arguments > DoubleRegister::NumRegisters()) {
stack_passed_words +=
2 * (num_double_arguments - DoubleRegister::NumRegisters());
}
} else {
// In the soft floating point calling convention, every double
// argument is passed using two registers.
num_reg_arguments += 2 * num_double_arguments;
}
// Up to four simple arguments are passed in registers r0..r3.
if (num_reg_arguments > kRegisterPassedArguments) {
stack_passed_words += num_reg_arguments - kRegisterPassedArguments;
}
return stack_passed_words;
}
void TurboAssembler::PrepareCallCFunction(int num_reg_arguments,
int num_double_arguments,
Register scratch) {
int frame_alignment = ActivationFrameAlignment();
int stack_passed_arguments = CalculateStackPassedWords(
num_reg_arguments, num_double_arguments);
if (frame_alignment > kPointerSize) {
UseScratchRegisterScope temps(this);
if (!scratch.is_valid()) scratch = temps.Acquire();
// Make stack end at alignment and make room for num_arguments - 4 words
// and the original value of sp.
mov(scratch, sp);
sub(sp, sp, Operand((stack_passed_arguments + 1) * kPointerSize));
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
and_(sp, sp, Operand(-frame_alignment));
str(scratch, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else if (stack_passed_arguments > 0) {
sub(sp, sp, Operand(stack_passed_arguments * kPointerSize));
}
}
void TurboAssembler::MovToFloatParameter(DwVfpRegister src) {
DCHECK(src == d0);
if (!use_eabi_hardfloat()) {
vmov(r0, r1, src);
}
}
// On ARM this is just a synonym to make the purpose clear.
void TurboAssembler::MovToFloatResult(DwVfpRegister src) {
MovToFloatParameter(src);
}
void TurboAssembler::MovToFloatParameters(DwVfpRegister src1,
DwVfpRegister src2) {
DCHECK(src1 == d0);
DCHECK(src2 == d1);
if (!use_eabi_hardfloat()) {
vmov(r0, r1, src1);
vmov(r2, r3, src2);
}
}
void TurboAssembler::CallCFunction(ExternalReference function,
int num_reg_arguments,
int num_double_arguments) {
UseScratchRegisterScope temps(this);
Register scratch = temps.Acquire();
Move(scratch, function);
CallCFunctionHelper(scratch, num_reg_arguments, num_double_arguments);
}
void TurboAssembler::CallCFunction(Register function, int num_reg_arguments,
int num_double_arguments) {
CallCFunctionHelper(function, num_reg_arguments, num_double_arguments);
}
void TurboAssembler::CallCFunction(ExternalReference function,
int num_arguments) {
CallCFunction(function, num_arguments, 0);
}
void TurboAssembler::CallCFunction(Register function, int num_arguments) {
CallCFunction(function, num_arguments, 0);
}
void TurboAssembler::CallCFunctionHelper(Register function,
int num_reg_arguments,
int num_double_arguments) {
DCHECK_LE(num_reg_arguments + num_double_arguments, kMaxCParameters);
DCHECK(has_frame());
// Make sure that the stack is aligned before calling a C function unless
// running in the simulator. The simulator has its own alignment check which
// provides more information.
#if V8_HOST_ARCH_ARM
if (emit_debug_code()) {
int frame_alignment = base::OS::ActivationFrameAlignment();
int frame_alignment_mask = frame_alignment - 1;
if (frame_alignment > kPointerSize) {
DCHECK(base::bits::IsPowerOfTwo(frame_alignment));
Label alignment_as_expected;
tst(sp, Operand(frame_alignment_mask));
b(eq, &alignment_as_expected);
// Don't use Check here, as it will call Runtime_Abort possibly
// re-entering here.
stop("Unexpected alignment");
bind(&alignment_as_expected);
}
}
#endif
// Save the frame pointer and PC so that the stack layout remains iterable,
// even without an ExitFrame which normally exists between JS and C frames.
if (isolate() != nullptr) {
Register scratch = r4;
Push(scratch);
Move(scratch, ExternalReference::fast_c_call_caller_pc_address(isolate()));
str(pc, MemOperand(scratch));
Move(scratch, ExternalReference::fast_c_call_caller_fp_address(isolate()));
str(fp, MemOperand(scratch));
Pop(scratch);
}
// Just call directly. The function called cannot cause a GC, or
// allow preemption, so the return address in the link register
// stays correct.
Call(function);
if (isolate() != nullptr) {
// We don't unset the PC; the FP is the source of truth.
Register scratch1 = r4;
Register scratch2 = r5;
Push(scratch1);
Push(scratch2);
Move(scratch1, ExternalReference::fast_c_call_caller_fp_address(isolate()));
mov(scratch2, Operand::Zero());
str(scratch2, MemOperand(scratch1));
Pop(scratch2);
Pop(scratch1);
}
int stack_passed_arguments = CalculateStackPassedWords(
num_reg_arguments, num_double_arguments);
if (ActivationFrameAlignment() > kPointerSize) {
ldr(sp, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else {
add(sp, sp, Operand(stack_passed_arguments * kPointerSize));
}
}
void TurboAssembler::CheckPageFlag(Register object, Register scratch, int mask,
Condition cc, Label* condition_met) {
DCHECK(cc == eq || cc == ne);
Bfc(scratch, object, 0, kPageSizeBits);
ldr(scratch, MemOperand(scratch, MemoryChunk::kFlagsOffset));
tst(scratch, Operand(mask));
b(cc, condition_met);
}
Register GetRegisterThatIsNotOneOf(Register reg1,
Register reg2,
Register reg3,
Register reg4,
Register reg5,
Register reg6) {
RegList regs = 0;
if (reg1.is_valid()) regs |= reg1.bit();
if (reg2.is_valid()) regs |= reg2.bit();
if (reg3.is_valid()) regs |= reg3.bit();
if (reg4.is_valid()) regs |= reg4.bit();
if (reg5.is_valid()) regs |= reg5.bit();
if (reg6.is_valid()) regs |= reg6.bit();
const RegisterConfiguration* config = RegisterConfiguration::Default();
for (int i = 0; i < config->num_allocatable_general_registers(); ++i) {
int code = config->GetAllocatableGeneralCode(i);
Register candidate = Register::from_code(code);
if (regs & candidate.bit()) continue;
return candidate;
}
UNREACHABLE();
}
void TurboAssembler::ComputeCodeStartAddress(Register dst) {
// We can use the register pc - 8 for the address of the current instruction.
sub(dst, pc, Operand(pc_offset() + Instruction::kPcLoadDelta));
}
void TurboAssembler::ResetSpeculationPoisonRegister() {
mov(kSpeculationPoisonRegister, Operand(-1));
}
} // namespace internal
} // namespace v8
#endif // V8_TARGET_ARCH_ARM