Skip to content

V
V8
Switch branch/tag
  1. 23 Apr, 2020 3 commits
    • Leszek Swirski's avatar
      [compile] Add an UnoptimizedCompileState class · 6458a529
      Leszek Swirski authored 
      Move the persistent compilation state and Isolate inputs (such as the
allocator, shared AST constants, hash seed, logger, etc.) which survives
across both parse and compile, out of ParseInfo and into a new
UnoptimizedCompileState class. Also add UnoptimizedCompilePerThreadState
for per-thread state such as stack limit and RCS.

In particular, this new state survives the ParseInfo being destructed,
which means it is available after off-thread finalization. This allows a
followup to access the PendingCompilationErrorHandler after finalization
and report errors on merge.

Bug: v8:10314
Change-Id: Ia186bc0f267c704efd771aa1895f50a4525a8364
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2105636
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67329}
      6458a529
    • Zhao Jiazhong's avatar
      [mips64][wasm-simd] Implement I64x2 splat extract_lane replace_lane · b9c3921d
      Zhao Jiazhong authored 
      Change-Id: I815979c232f0c781a76dd7954fbba9edabec7359
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2152071Reviewed-by: 's avatarZhi An Ng <zhin@chromium.org>
Reviewed-by: 's avatarBill Budge <bbudge@chromium.org>
Commit-Queue: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#67328}
      b9c3921d
    • Timothy Gu's avatar
      [builtins] Clean up the use of class_name / ES5 [[Class]] · 29c1eab9
      Timothy Gu authored 
      Before ES2015, the ES spec had a [[Class]] internal slot for all
objects, which Object.prototype.toString() would use to figure the
returned string. Post-ES2015, the [[Class]] slot was removed in spec for
all objects, with the @@toStringTag well-known symbol the proper way to
change Object.prototype.toString() output.

At the time, spec-identical handling without the use of [[Class]] was
implemented in V8 for all objects other than API objects, where issues
with the Web IDL spec [1] prevented Blink, and hence V8, to totally
migrate to @@toStringTag. However, since 2016 [2] Blink has been setting
@@toStringTag on API class prototypes to manage the
Object.prototype.toString() output, so the legacy [[Class]] handling in
V8 has not been necessary for the past couple of years.

This CL removes the remaining legacy [[Class]] handling in
Object.prototype.toString(), JSReceiver::class_name(), and
GetConstructorName(). However, it does not remove the class_name field
in FunctionTemplateInfo, as it is still used for the `name` property of
created functions.

This CL also cleans up other places in the codebase that still reference
[[Class]].

This change should have minimal impact on web-compatibility. For the
change to be observable, a script must do one of the following:

1. delete APIConstructor.prototype[Symbol.toStringTag];
2. Object.setPrototypeOf(apiObject, somethingElse);

Before this CL, these changes will not change the apiObject.toString()
output. But after this CL, they will make apiObject.toString() show
"[object Object]" (in the first case) or the @@toStringTag of the other
prototype (in the latter case).

However, both are deemed unlikely. @@toStringTag is not well-known
feature of JavaScript, nor does it get tampered much on API
constructors. In the second case, setting the prototype of an API object
would effectly render the object useless, as all its methods (including
property getters/setters) would no longer be accessible.

Currently, @@toStringTag-based API object branding is not yet
implemented by other browsers. This V8 bug in particular has been an
impediment to standardizing toString behavior. Fixing this bug will
unblock [3] and lead to a better Web IDL spec, and better toString()
compatibility for all.

[1]: https://www.w3.org/Bugs/Public/show_bug.cgi?id=28244
[2]: https://crrev.com/909c0d7d5a53c8526ded351683c65ea7d17531d4
[3]: https://github.com/heycam/webidl/pull/357

Bug: chromium:793406
Cq-Include-Trybots: luci.chromium.try:linux-rel
Change-Id: Iceded24e37afa2646ec385d5018909f55b177f93
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2146996
Commit-Queue: Timothy Gu <timothygu@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67327}
      29c1eab9
  3. 22 Apr, 2020 29 commits
  5. 21 Apr, 2020 8 commits