[modules] Store Module metadata in per-Context EmbedderData

This is a re-land of https://codereview.chromium.org/2393303002/ with
an additional call to DisposeModuleEmbedderData() added to fix lsan failures.

Unifies the approaches used for storing the specifier -> module mapping
and the module -> directory mapping, using std::unordered_maps for both
and storing them per-Context.

This requires adding a method to the v8::Module API to get a hash code
for a Module, but allows slimming down the API in return: gone are
SetEmbedderData/GetEmbedderData, along with the fourth argument
to ResolveModuleCallback.

Besides a simpler API, this allows d8 to get closer to the HTML loader,
which requires each Realm to have a persistent module map (though this
capability is not yet exercised by any tests).

BUG=v8:1569
TBR=neis@chromium.org,jochen@chromium.org

Review-Url: https://codereview.chromium.org/2405313002
Cr-Commit-Position: refs/heads/master@{#40186}
11 files changed
tree: 16f696ec81d96e5af1fb0920b81dfecd0ee99e73
  1. benchmarks/
  2. build_overrides/
  3. docs/
  4. gni/
  5. gypfiles/
  6. include/
  7. infra/
  8. samples/
  9. src/
  10. test/
  11. testing/
  12. third_party/
  13. tools/
  14. .clang-format
  15. .gitignore
  16. .gn
  17. .ycm_extra_conf.py
  18. AUTHORS
  19. BUILD.gn
  20. ChangeLog
  21. CODE_OF_CONDUCT.md
  22. codereview.settings
  23. DEPS
  24. LICENSE
  25. LICENSE.fdlibm
  26. LICENSE.strongtalk
  27. LICENSE.v8
  28. LICENSE.valgrind
  29. Makefile
  30. Makefile.android
  31. OWNERS
  32. PRESUBMIT.py
  33. README.md
  34. snapshot_toolchain.gni
  35. 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.