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  1. 13 Feb, 2018 5 commits
    • Benedikt Meurer's avatar
      [builtins] Optimize PromiseResolveThenableJob for the common case. · 1f8dcc5d
      Benedikt Meurer authored 
      The idea here is that in case the `thenable` is a JSPromise and `then`
is the initial `Promise.prototype.then` method, and the @@species lookup
chain is intact, we can skip creating the temporary promise and the
closures (with the shared context), and instead directly call into our
PerformPromiseThen. This is sound since - given above mentioned
conditions - our short-cut

  PerformPromiseThen(thenable, undefined, undefined, promise_to_resolve)

is not observably different from the actual

  resolve, reject = CreateResolvingFunctions(promise_to_resolve)
  result_capability = NewPromiseCapability(%Promise%)
  PerformPromiseThen(thenable, resolve, reject, result_capability)

except through PromiseHooks (and potentially via the async stack
traces). So we disable the fast-path if either promise hooks are enabled
or the debugger is active for now.

This improves the performance on the wikipedia benchmark by 20-25% and
the bluebird-doxbee benchmark by around 20%.

Bug: v8:7253
Change-Id: I23c92ad365c2b71d65057573f2d8febe2afe00b0
Reviewed-on: https://chromium-review.googlesource.com/911800
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarSathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51261}
      1f8dcc5d
    • Benedikt Meurer's avatar
      [builtins] Refactor the promise resolution and rejection logic. · c0412961
      Benedikt Meurer authored 
      This introduces dedicated builtins

  - FulfillPromise,
  - RejectPromise, and
  - ResolvePromise,

which perform the corresponding operations from the language
specification, and removes the redundant entry points and the
excessive inlining of these operations into other builtins. We
also add the same logic on the C++ side, so that we don't need
to go into JavaScript land when resolving/rejecting from the
API.

The C++ side has a complete implementation, including full support
for the debugger and the current PromiseHook machinery. This is to
avoid constantly crossing the boundary for those cases, and to also
simplify the CSA side (and soon the TurboFan side), where we only
do the fast-path and bail out to the runtime for the general handling.

On top of this we introduce %_RejectPromise and %_ResolvePromise,
which are entry points used by the bytecode and parser desugarings
for async functions, and also used by the V8 Extras API. Thanks to
this we can uniformly optimize these in TurboFan, where we have
corresponding operators JSRejectPromise and JSResolvePromise, which
currently just call into the builtins, but middle-term can be further
optimized, i.e. to skip the "then" lookup for JSResolvePromise when
we know something about the resolution.

In TurboFan we can also already inline the default PromiseCapability
[[Reject]] and [[Resolve]] functions, although this is not as effective
as it can be right now, until we have inlining support for the Promise
constructor (being worked on by petermarshall@ right now) and/or SFI
based CALL_IC feedback.

Overall this change is meant as a refactoring without significant
performance impact anywhere; it seems to improve performance of
simple async functions a bit, but otherwise is neutral.

Bug: v8:7253
Change-Id: Id0b979f9b2843560e38cd8df4b02627dad4b6d8c
Reviewed-on: https://chromium-review.googlesource.com/911632Reviewed-by: 's avatarSathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51260}
      c0412961
    • Sergiy Byelozyorov's avatar
      Add Peter as an owner of the JSTests benchmark · 07955372
      Sergiy Byelozyorov authored 
      This information is useful to know whom to assign bugs to when these tests are
crashing on our infrastructure.

R=petermarshall@chromium.org

No-Try: true
Change-Id: Ia165e0236602cae73e144011537d642e3535fa6b
Reviewed-on: https://chromium-review.googlesource.com/908563
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: 's avatarPeter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51259}
      07955372
    • Sergiy Byelozyorov's avatar
      Whitespace CL · 5e006978
      Sergiy Byelozyorov authored 
      R=sergiyb@google.com

No-Try: true
Bug: chromium:616879
Change-Id: If52f419c7447c88313526fceed10e7dd2e89b10c
Reviewed-on: https://chromium-review.googlesource.com/913948
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: 's avatarSergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51258}
      5e006978
    • Sergiy Byelozyorov's avatar
      Correct try bucket name for internal V8 bots on swarming · d8dc1fc5
      Sergiy Byelozyorov authored 
      TBR=machenbach@chromium.org

No-Try: true
Bug: chromium:616879
Change-Id: I49d3f12216cdc2d26761e8f82fef18512d8eb6fd
Reviewed-on: https://chromium-review.googlesource.com/915141
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: 's avatarSergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51257}
      d8dc1fc5
  3. 12 Feb, 2018 30 commits
  5. 10 Feb, 2018 3 commits
  7. 09 Feb, 2018 2 commits
    • Ben L. Titzer's avatar
      Normalize names of call descriptor local variables · 855cb90d
      Ben L. Titzer authored 
      This is a purely cosmetic change. Rename all local variables and
parameters of type CallDescriptor* to "call_descriptor".
For locals that are now named "call_descriptor", use auto upon
initialization, following the Google style guide
(https://google.github.io/styleguide/cppguide.html#auto).

Note: fields in structs and classes were not renamed in this CL.

R=clemensh@chromium.org,mstarzinger@chromium.org,jarin@chromium.org

Change-Id: Ic6f7afdba12f7b97741b098a9d0e0f58c41c587e
Reviewed-on: https://chromium-review.googlesource.com/909866
Commit-Queue: Ben Titzer <titzer@chromium.org>
Reviewed-by: 's avatarMichael Starzinger <mstarzinger@chromium.org>
Reviewed-by: 's avatarClemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51223}
      855cb90d
    • Benedikt Meurer's avatar
      [ic] Support negative indices for typed array OOB accesses. · 317fad95
      Benedikt Meurer authored 
      Extend the current OOB support for typed arrays to also handle the
negative integer indices in the fast-path. This is safe because in
ECMAScript we never look up integer indexed properties (including
negative indices) on typed arrays in the prototype chain.

This reduces the performance cliff shown in the benchmark on the
relevant bug from

  console.timeEnd: Runtime deopt, 596.185000
  console.timeEnd: Runtime deopt, 1444.289000
  console.timeEnd: Runtime deopt, 1445.191000
  console.timeEnd: Runtime deopt, 1443.008000

to

  console.timeEnd: Runtime deopt, 590.017000
  console.timeEnd: Runtime deopt, 784.899000
  console.timeEnd: Runtime deopt, 792.428000
  console.timeEnd: Runtime deopt, 786.740000

which corresponds to a 2x improvement overall. It's not for free,
especially not in this benchmark, but the cliff isn't as bad as
it was previously.

Bug: v8:7027
Change-Id: Icf8a7ee87bb7ebc54f82c1b9166fc5e78c12bc0e
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/911574Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51222}
      317fad95