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  1. 27 Mar, 2018 1 commit
  3. 16 Feb, 2018 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Properly optimize calls to promise extras. · 13ca9a0f
      Benedikt Meurer authored 
      Add TurboFan inlining support for the following V8 Extras:

 - v8.createPromise
 - v8.rejectPromise
 - v8.resolvePromise

These are used by the streams implementation in Chrome currently, and
were previously not inlined into TurboFan, although TurboFan already
had all the necessary functionality (namely the JSCreatePromise,
JSRejectPromise and JSResolvePromise operators). We might eventually
want to use these functions in Node core as well (at least short-term
for Node 10), to replace the C++ internal API functions with the same
name that are currently being used by parts of Node core.

For this to work, the rejectPromise and resolvePromise builtins had
to be moved back to CSA, as for JavaScript builtins we still have the
policy that the optimizing compiler must not inline them. But that's
straight-forward since the CSA has all the necessary functionality
available anyways.

Bug: v8:7253
Change-Id: I39ab015c379956cd58ace866e17f8ec23b2257b2
Reviewed-on: https://chromium-review.googlesource.com/924146Reviewed-by: 's avatarSathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51332}
      13ca9a0f
  5. 13 Feb, 2018 1 commit
    • 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
  7. 06 Feb, 2018 1 commit
    • Mathias Bynens's avatar
      [v8-extras] Remove `simpleBind` · fefee7dc
      Mathias Bynens authored 
      The `simpleBind` function exposed by V8 Extras was initially added to
work around the terrible performance of `Function.prototype.bind` at
the time. Nowadays `Function.prototype.bind` is significantly faster
and fully optimized by TurboFan, however, so there’s no need for the
`simpleBind` helper anymore.

Bug: chromium:807522
Change-Id: I1a0456e2aa34f92a3c9a0234a812b660f969d016
Reviewed-on: https://chromium-review.googlesource.com/903164Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51108}
      fefee7dc
  9. 19 Dec, 2017 1 commit
  11. 15 Dec, 2017 2 commits
  13. 30 Jun, 2017 1 commit
    • Igor Sheludko's avatar
      [runtime] Cleanup js/prologue.js. · f79b3d4e
      Igor Sheludko authored 
      This CL removes unused utils.InstallFunctions, utils.InstallGetter(),
utils.SetFunctionName, utils.OverrideFunction and respective runtime
functions (%FunctionSetSharedName and %FunctionRemovePrototype).

This CL is one of a series of cleanup CL which are the preliminary steps for
improving function closures creation.

Bug: v8:6459
Change-Id: I0fb5940ed628f0c1958f585411e2fca3e2038054
Reviewed-on: https://chromium-review.googlesource.com/548037
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46336}
      f79b3d4e
  15. 06 Jun, 2017 1 commit
    • Igor Sheludko's avatar
      [parser] Introduce SharedFunctionInfo::has_shared_name(). · 9a2c18f5
      Igor Sheludko authored 
      Properly propagate the fact that the function has a statically known name from
parser to SharedFunctionInfo objects. The empty string that has been set as
name before this CL does not help to distinguish cases like:
  var o1 = { ''(){} };
  var o1 = { [foo()](){} };
or
  var o2 = { get ''(){} };
  var o2 = { get [foo()](){} };

This is a preliminary step for using different layouts for closure objects with
and without computed names.

TBR=bmeurer@chromium.org, marja@chromium.org

Bug: v8:6459
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I10afa6f4bda7881c3714711a75f720f83c1d875d
Reviewed-on: https://chromium-review.googlesource.com/522073
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45744}
      9a2c18f5
  17. 24 Apr, 2017 1 commit
  19. 19 Apr, 2017 1 commit
  21. 06 Apr, 2017 1 commit
  23. 31 Mar, 2017 1 commit
  25. 13 Mar, 2017 1 commit
    • binji's avatar
      Reland moving Atomics builtins to C++ · 65200967
      binji authored 
      This reverts the previous revert, commit
5a04f4fd.

Previously reverted changes:

>    Revert "[SAB] Move Atomics builtins to C++"
>
>     This reverts commit 2b9840d8.
>
>     Revert "[SAB] Remove unreachable Uint8Clamped atomics paths"
>
>     This reverts commit d1160fb1.
>
>     Revert "Remove tiny unit test for MinSimple/MaxSimple"
>
>     This reverts commit 837760ec.
>
>     Revert "Remove infrastructure for experimental JS natives"
>
>     This reverts commit 8cfe45b6.

These changes were reverted to improve a perf regression on a Chrome
bot. Since then, the regression has reappeared, then disappeared again
all from seemingly unrelated changes.

BUG=v8:6033
TBR=adamk@chromium.org,hpayer@chromium.org,yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2732213005
Cr-Commit-Position: refs/heads/master@{#43758}
      65200967
  27. 27 Feb, 2017 1 commit
  29. 24 Feb, 2017 1 commit
    • adamk's avatar
      Remove infrastructure for experimental JS natives · 8cfe45b6
      adamk authored 
      Now that no harmony-flagged features are implemented in experimental
JS, most of this is simply dead code.

As PostExperimentals() is no longer needed, I also removed the use of
Import() in the debug context, allowing the deletion of PostDebug()
along with PostExperimentals(); cleanup code is moved to the
end of PostNatives.

Also gets rid of some longer-dead code in prologue.js related to
TypedArrays, and some duplicate code for setting up SharedArrayBuffer
builtins.

Review-Url: https://codereview.chromium.org/2705293004
Cr-Commit-Position: refs/heads/master@{#43418}
      8cfe45b6
  31. 23 Feb, 2017 2 commits
  33. 15 Feb, 2017 1 commit
    • littledan's avatar
      [bootstrapper] Remove Intl experimental natives files · 407d6bf1
      littledan authored 
      These experimental natives previously only installed functions to the
appropriate parent. In this patch, the exports container is retained
so that the bootstrapper may install the functions instead. This
change is intended to reduce startup time. SharedArrayBuffer retains
some experimental natives exported from JS; this may be addressed
in a follow-on patch. The patch includes some minor cleanup of the
bootstrap process by removing "experimental exports", which was unused.

R=yangguo@chromium.org
BUG=v8:5880
CQ_INCLUDE_TRYBOTS=master.tryserver.v8:v8_linux_noi18n_rel_ng

Review-Url: https://codereview.chromium.org/2683083003
Cr-Commit-Position: refs/heads/master@{#43221}
      407d6bf1
  35. 17 Jan, 2017 1 commit
  37. 04 Jan, 2017 1 commit
  39. 14 Oct, 2016 1 commit
  41. 13 Oct, 2016 1 commit
    • jgruber's avatar
      [regexp] Port RegExp.prototype[@@replace] · 33a4faa4
      jgruber authored 
      This moves the implementation of @@replace from regexp.js to builtins-regexp.cc
(the TurboFan fast path) and runtime-regexp.cc (slow path). The fast path
handles all cases in which the regexp itself is an unmodified JSRegExp
instance, the given 'replace' argument is not callable and does not contain any
'$' characters (i.e. we are doing a string replacement).

BUG=v8:5339

Review-Url: https://codereview.chromium.org/2398423002
Cr-Commit-Position: refs/heads/master@{#40253}
      33a4faa4
  43. 24 Sep, 2016 1 commit
    • littledan's avatar
      Move async/await JS support code out of experimental natives · 13b8a123
      littledan authored 
      The file formerly known as src/js/harmony-async-await.js does not
expose anything directly to JavaScript code; it just makes a few
functions available on the native context for the parser desugaring
to expand into. Experimental natives have various issues with
larger amounts of code, so this patch moves the JS builtins to
support async functions out of experimental natives and into the
core snapshot. The change would be done eventually anyway, but this
patch does it before removing the flag to support shipping the
feature while avoiding the pitfalls of experimental natives.

Drive by cleanup: remove more unused functions from the whitelist for experimental natives.

BUG=v8:5427,v8:4483

Review-Url: https://codereview.chromium.org/2365123002
Cr-Commit-Position: refs/heads/master@{#39706}
      13b8a123
  45. 23 Sep, 2016 1 commit
    • littledan's avatar
      Improve stack traces for async functions · f296dad9
      littledan authored 
      This patch tracks the stack of async functions differently from other
Promise async stack tracking. With this patch, the stack trace of a
callstack of async functions should look similarly to the call stack
if all of the functions were synchronous. An example can be found in
the updated test expectations: https://codereview.chromium.org/2362923002 .

The new stack traces are implemented using existing mechanisms in the
inspector. The inspector has two ways to save async stack traces: recurring
and non-recurring stacks. An example of a non-recurring stack is setTimeout,
and a recurring one is saved for setInterval. Recurring stacks are deleted
only when a special "cancel" function is called, rather than being deleted
after being used the first time. Previous Promise async stack tracking always
used non-recurring stacks.

For async functions, this patch saves a recurring stack. The top frame of
the stack is duplicated, as the resuming function contains a similar frame;
the devtools frontend is responsible for removing or marking this frame,
which it can do based on seeing the [async function] line which follows it.
The second frame will instead be provided by the resuming execution
context. The recurring stack is saved when the async function is entered, and
it is deleted from a finally block. The id of the stack is saved in the outer
Promise being constructed by the async function. When an intermediate
throwaway Promise will be triggered as a reaction, it will be identified as
such based on its debugging metadata, and the corresponding async function's
recurring stack will be used.

BUG=v8:4483

Review-Url: https://codereview.chromium.org/2357423002
Cr-Commit-Position: refs/heads/master@{#39695}
      f296dad9
  47. 20 Sep, 2016 2 commits
    • littledan's avatar
      Reland Async/await Promise dependency graph · 1b414e28
      littledan authored 
      This patch knits together Promises returned by async/await such that when
one async function awaits the result of another one, catch prediction works
across the boundaries, whether the exception comes synchronously or
asynchronously. Edges are added in three places:
- When a locally uncaught await happens, if the value passed into await
  is a Promise, from the awaited value to the Promise under construction
  in the broader async function
- From a "throwaway" Promise, which may be found on the Promise debug
  stack, to the Promise under construction in the async function that
  surrounds it
- When a Promise is resolved with another Promise (e.g., when returning a
  Promise from an async function)

In this reland, the caught tests are broken up into four parts to avoid
timeouts.

BUG=v8:5167

Review-Url: https://codereview.chromium.org/2346363004
Cr-Commit-Position: refs/heads/master@{#39564}
      1b414e28
    • littledan's avatar
      Revert of Async/await Promise dependency graph (patchset #30 id:550001 of... · 100336f5
      littledan authored 
      Revert of Async/await Promise dependency graph (patchset #30 id:550001 of https://codereview.chromium.org/2317383002/ )

Reason for revert:
Need to break up test into smaller tests to avoid timeouts

Original issue's description:
> Async/await Promise dependency graph
>
> This patch knits together Promises returned by async/await such that when
> one async function awaits the result of another one, catch prediction works
> across the boundaries, whether the exception comes synchronously or
> asynchronously. Edges are added in three places:
> - When a locally uncaught await happens, if the value passed into await
>   is a Promise, from the awaited value to the Promise under construction
>   in the broader async function
> - From a "throwaway" Promise, which may be found on the Promise debug
>   stack, to the Promise under construction in the async function that
>   surrounds it
> - When a Promise is resolved with another Promise (e.g., when returning a
>   Promise from an async function)
>
> BUG=v8:5167
>
> Committed: https://crrev.com/7265fdde7c76b9f875b40b0b139515936d491d64
> Cr-Commit-Position: refs/heads/master@{#39522}

TBR=adamk@chromium.org,jgruber@chromium.org,kozyatinskiy@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5167

Review-Url: https://codereview.chromium.org/2351953002
Cr-Commit-Position: refs/heads/master@{#39523}
      100336f5
  49. 19 Sep, 2016 1 commit
    • littledan's avatar
      Async/await Promise dependency graph · 7265fdde
      littledan authored 
      This patch knits together Promises returned by async/await such that when
one async function awaits the result of another one, catch prediction works
across the boundaries, whether the exception comes synchronously or
asynchronously. Edges are added in three places:
- When a locally uncaught await happens, if the value passed into await
  is a Promise, from the awaited value to the Promise under construction
  in the broader async function
- From a "throwaway" Promise, which may be found on the Promise debug
  stack, to the Promise under construction in the async function that
  surrounds it
- When a Promise is resolved with another Promise (e.g., when returning a
  Promise from an async function)

BUG=v8:5167

Review-Url: https://codereview.chromium.org/2317383002
Cr-Commit-Position: refs/heads/master@{#39522}
      7265fdde
  51. 16 Sep, 2016 1 commit
  53. 15 Sep, 2016 1 commit
  55. 13 Sep, 2016 1 commit
    • littledan's avatar
      Mark await expressions as caught or uncaught · edb4d315
      littledan authored 
      Handle some examples of the "asynchronous case" by marking await expressions
as either caught or uncaught; in the caught case, this marks the Promise passed
in as having a catch predicted. The marking is done in AST numbering, which
chooses between two different runtime function calls based on catch prediction.

BUG=v8:5167

Review-Url: https://codereview.chromium.org/2276243002
Cr-Commit-Position: refs/heads/master@{#39394}
      edb4d315
  57. 07 Sep, 2016 1 commit
    • bmeurer's avatar
      [builtins] Migrate Number predicates and make them optimizable. · 7ac19fe5
      bmeurer authored 
      Migrate the isNaN, isFinite, Number.isFinite, Number.isInteger,
Number.isSafeInteger and Number.isNaN predicates to TurboFan
builtins and make them optimizable (for certain input types) in
JavaScript callees being optimized by TurboFan. That means both
the baseline and the optimized version is now always at maximum,
consistent performance. Especially TurboFan suffered from poor
baseline (and optimized) performance because it cannot play the
same weird tricks that Crankshaft plays for %_IsSmi.

This also adds a bunch of new tests to properly cover the use
of the Harmony predicates in optimized code.

R=franzih@chromium.org
BUG=v8:5049,v8:5267

Review-Url: https://codereview.chromium.org/2313073002
Cr-Commit-Position: refs/heads/master@{#39242}
      7ac19fe5
  59. 06 Sep, 2016 1 commit
  61. 01 Sep, 2016 1 commit
  63. 26 Aug, 2016 1 commit
    • littledan's avatar
      Desugar async/await to create the resulting Promise upfront · 5386c006
      littledan authored 
      As part of the work to implement catch prediction for async functions,
the resulting Promise that is the output of the function needs to be
available earlier for a couple reasons:
- To be able to do %DebugPushPromise/%DebugPopPromise over the body
  of the async function
- To be able to pass the resulting promise into AsyncFunctionAwait
  in order to set up the dependency chains

This patch creates the Promise earlier and pushes it onto the debug
stack; a later patch will set up the dependency chain. Although the
debug stack is set up, it's not anticipated that this will change
the catch prediction helpfully yet, as everything will still likely
be predicted as 'caught' for now, as before.

R=caitp@igalia.com,yangguo@chromium.org
CC=neis@chromium.org,gsathya@chromium.org
BUG=v8:5167

Review-Url: https://codereview.chromium.org/2233923003
Cr-Commit-Position: refs/heads/master@{#38957}
      5386c006
  65. 22 Aug, 2016 1 commit
  67. 09 Aug, 2016 1 commit
  69. 06 Aug, 2016 1 commit
    • littledan's avatar
      [promise] Async/await edge case spec compliance fix · 7826bfa7
      littledan authored 
      - Don't read .constructor when returning a Promise from an async function.
  Instead, call out to the internals of Promise.resolve directly.
  This is done by adding back in an "optimization" from an earlier form of
  the async/await code written by Caitlin Potter.
- Async functions always return a new Promise with a distinct identity,
  even if they simply return another Promise.

R=caitp@igalia.com
BUG=v8:4483

Review-Url: https://codereview.chromium.org/2219623002
Cr-Commit-Position: refs/heads/master@{#38404}
      7826bfa7
  71. 04 Aug, 2016 1 commit
    • caitp's avatar
      [promise] separate PerformPromiseThen from PromiseThen · 0272aa50
      caitp authored 
      The `PerformPromiseThen` spec-internal operation is used by the async functions
proposal, in order to ensure that AwaitExpressions are not observable via
usual mechanisms/hooks, such as Symbol.species.

BUG=v8:5253
R=littledan@chromium.org, adamk@chromium.org, gsathya@chromium.org, yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2209433003
Cr-Commit-Position: refs/heads/master@{#38353}
      0272aa50
  73. 03 Aug, 2016 1 commit