[Interpreter] Change the output format of generate-bytecode-expectations.

Now the tool produces a far more readable output format, which bears a
lot of resemblance to YAML. In fact, the output should be machine
parseable as such, one document per testcase. However, the output format
may be subject to changes in future, so don't rely on this property.

In general, the output format has been optimized for producing a meaningful
textual diff, while keeping a decent readability as well. Therefore, not
everything is as compact as it could be, e.g. for an empty const pool we get:

    constant pool: [
    ]

instead of:

    constant pool: []

Also, trailing commas are always inserted in lists.

Additionally, now the tool accepts its output format as input. When
operating in this mode, all the snippets are extracted, processed and
the output is then emitted as usual. If nothing has changed, the output
should match the input. This is very useful for catching bugs in the
bytecode generation by running a textual diff against a known-good file.

The core (namely bytecode-expectations.cc) has been extracted from the
original cc file, which provides the utility as usual. The definitions
in the matching header of the library have been moved into the
v8::internal::interpreter namespace.

The library exposes a class ExpectationPrinter, with a method
PrintExpectation, which takes a test snippet as input, and writes the
formatted expectation to the supplied stream. One might then use a
std::stringstream to retrieve the results as a string and run it through
a diff utility.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1688383003

Cr-Commit-Position: refs/heads/master@{#33997}
4 files changed
tree: 06ef83d8030caa9e3c54ccbbb8a5144243f6593a
  1. benchmarks/
  2. build/
  3. docs/
  4. include/
  5. infra/
  6. samples/
  7. src/
  8. test/
  9. testing/
  10. third_party/
  11. tools/
  12. .clang-format
  13. .gitignore
  14. .ycm_extra_conf.py
  15. AUTHORS
  16. BUILD.gn
  17. ChangeLog
  18. codereview.settings
  19. DEPS
  20. LICENSE
  21. LICENSE.strongtalk
  22. LICENSE.v8
  23. LICENSE.valgrind
  24. Makefile
  25. Makefile.android
  26. Makefile.nacl
  27. OWNERS
  28. PRESUBMIT.py
  29. README.md
  30. snapshot_toolchain.gni
  31. WATCHLISTS
README.md

V8 JavaScript Engine

V8 is Google's open source JavaScript engine.

V8 implements ECMAScript as specified in ECMA-262.

V8 is written in C++ and is used in Google Chrome, the open source browser from Google.

V8 can run standalone, or can be embedded into any C++ application.

V8 Project page: https://github.com/v8/v8/wiki

Getting the Code

Checkout depot tools, and run

    fetch v8

This will checkout V8 into the directory v8 and fetch all of its dependencies. To stay up to date, run

    git pull origin
    gclient sync

For fetching all branches, add the following into your remote configuration in .git/config:

    fetch = +refs/branch-heads/*:refs/remotes/branch-heads/*
    fetch = +refs/tags/*:refs/tags/*

Contributing

Please follow the instructions mentioned on the V8 wiki.