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  1. 24 Oct, 2018 1 commit
    • Benedikt Meurer's avatar
      [turbofan] ReceiverOrNullOrUndefined feedback for JSEqual. · f19c4a59
      Benedikt Meurer authored 
      This changes the ReceiverOrOddball feedback on JSStrictEqual to
ReceiverOrNullOrUndefined feedback, which can also safely be
consumed by JSEqual (we cannot generally accept any oddball here
since booleans trigger implicit conversions, unfortunately).
Thus we replace the previously introduced CheckReceiverOrOddball
with CheckReceiverOrNullOrUndefined, and drop CheckOddball, since
we will no longer collect Oddball feedback separately.

TurboFan will then turn a JSEqual[ReceiverOrNullOrUndefined] into
a sequence like this:

```
left = CheckReceiverOrNullOrUndefined(left);
right = CheckReceiverOrNullOrUndefined(right);
result = if ObjectIsUndetectable(left) then
           ObjectIsUndetectable(right)
         else
           ReferenceEqual(left, right);
```

This significantly improves the peak performance of abstract equality
with Receiver, Null or Undefined inputs. On the test case outlined in
http://crbug.com/v8/8356 we go from

  naive: 2946 ms.
  tenary: 2134 ms.

to

  naive: 2230 ms.
  tenary: 2250 ms.

which corresponds to a 25% improvement on the abstract equality case.
For regular code this will probably yield more performance, since we
get rid of the JSEqual operator, which might have arbitrary side
effects and thus blocks all kinds of TurboFan optimizations. The
JSStrictEqual case is slightly slower now, since it has to rule out
booleans as well (even though that's not strictly necessary, but
consistency is key here).

This way developers can safely use `a == b` instead of doing a dance
like `a == null ? b == null : a === b` (which is what dart2js does
right now) when both `a` and `b` are known to be Receiver, Null or
Undefined. The abstract equality is not only faster to parse than
the tenary, but also generates a shorter bytecode sequence. In the
test case referenced in http://crbug.com/v8/8356 the bytecode for
`naive` is

```
StackCheck
Ldar a1
TestEqual a0, [0]
JumpIfFalse [5]
LdaSmi [1]
Return
LdaSmi [2]
Return
```

which is 14 bytes, whereas the `tenary` function generates

```
StackCheck
Ldar a0
TestUndetectable
JumpIfFalse [7]
Ldar a1
TestUndetectable
Jump [7]
Ldar a1
TestEqualStrict a0, [0]
JumpIfToBooleanFalse [5]
LdaSmi [1]
Return
LdaSmi [2]
Return
```

which is 24 bytes. So the `naive` version is 40% smaller and requires
fewer bytecode dispatches.

Bug: chromium:898455, v8:8356
Change-Id: If3961b2518b4438700706b3bd6071d546305e233
Reviewed-on: https://chromium-review.googlesource.com/c/1297315Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56948}
      f19c4a59
  3. 18 Sep, 2018 1 commit
  5. 17 Jul, 2018 1 commit
  7. 19 Jun, 2018 1 commit
  9. 18 Jun, 2018 1 commit
  11. 07 May, 2018 1 commit
  13. 04 May, 2018 1 commit
    • Ben L. Titzer's avatar
      [compiler] Factor MachineGraph out from JSGraph · bc218a2e
      Ben L. Titzer authored 
      This CL factors the parts of the JSGraph that only depend on the
machine part of JSGraph into a separate base class, MachineGraph.
This helps separate the two layers and also allows the MachineGraph
to be constructed without an Isolate, which is needed for fully
asynchronous compilation, a goal for WASM.

R=mstarzinger@chromium.org
CC=jarin@chromium.org, mvstanton@chromium.org

BUG=v8:7721

Change-Id: Ie8bc3de40159332645dcb3cadcee581e1bf9830a
Reviewed-on: https://chromium-review.googlesource.com/1043746Reviewed-by: 's avatarMichael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52990}
      bc218a2e
  15. 02 Feb, 2018 1 commit
  17. 04 Jan, 2018 2 commits
  19. 03 Jan, 2018 1 commit
  21. 16 Nov, 2017 1 commit
    • Tobias Tebbi's avatar
      Reland^6 "[turbofan] eagerly prune None types and deadness from the graph" · 19ac10e5
      Tobias Tebbi authored 
      Reland of https://chromium-review.googlesource.com/c/v8/v8/+/727893
The crashes should be fixed by https://chromium-review.googlesource.com/c/v8/v8/+/763531

Original change's description:
> Revert "Reland^5 "[turbofan] eagerly prune None types and deadness from the graph""
> 
> This reverts commit ac0661b3.
> 
> Reason for revert: Clusterfuzz unhappy: chromium:783019 chromium:783035
> 
> Original change's description:
> > Reland^5 "[turbofan] eagerly prune None types and deadness from the graph"
> >
> > This gives up on earlier attempts to interpret DeadValue as a signal of
> > unreachable code. This does not work because free-floating dead value
> > nodes, and even pure branch nodes that use them, can get scheduled so
> > early that they get reachable. Instead, we now eagerly remove branches
> > that use DeadValue in DeadCodeElimination and replace DeadValue inputs
> > to value phi nodes with dummy values.
> >
> > Reland of https://chromium-review.googlesource.com/715716
> >
> > Bug: chromium:741225 chromium:776256
> > Change-Id: I251efd507c967d4a8882ad8fd2fd96c4185781fe
> > Reviewed-on: https://chromium-review.googlesource.com/727893
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#49188}
> 
> TBR=jarin@chromium.org,tebbi@chromium.org
> 
> Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
> Change-Id: I6a8fa3a08ce2824a858ae01817688e63ed1f442e
> Reviewed-on: https://chromium-review.googlesource.com/758770
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49262}

TBR=jarin@chromium.org,tebbi@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
Change-Id: I6c02b4beb02997ec34015ed2f6791a93c70f5e36
Reviewed-on: https://chromium-review.googlesource.com/772150
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49429}
      19ac10e5
  23. 14 Nov, 2017 1 commit
    • Michael Stanton's avatar
      Revert "[TurboFan] Diagnostic code to track down bug in representation selection" · ebe6d7a9
      Michael Stanton authored 
      This reverts commit f010b28f.

Reason for revert: Introduces a clusterfuzz issue and CAnary crash

Original change's description:
> [TurboFan] Diagnostic code to track down bug in representation selection
> 
> We need to characterize the types of dead (IrOpcode::kDead) nodes
> introduced in compilation phases prior to representation selection.
> Normally, a dead node isn't expected at the start of this phase. The
> question is, which phase introduced the dead node and failed to
> deal with it properly?
> 
> Bug: chromium:780658
> Change-Id: Ief5b45480bb7d704a2d09dafd60b5d389e0fd42e
> Reviewed-on: https://chromium-review.googlesource.com/765968
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Michael Stanton <mvstanton@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49328}

TBR=mvstanton@chromium.org,mstarzinger@chromium.org

Change-Id: I5d628eb1de630ce4a353b6ef0f80fd74ad740f17
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:780658
Reviewed-on: https://chromium-review.googlesource.com/768747Reviewed-by: 's avatarMichael Stanton <mvstanton@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49347}
      ebe6d7a9
  25. 13 Nov, 2017 1 commit
  27. 09 Nov, 2017 1 commit
    • Tobias Tebbi's avatar
      Revert "Reland^5 "[turbofan] eagerly prune None types and deadness from the graph"" · c899637d
      Tobias Tebbi authored 
      This reverts commit ac0661b3.

Reason for revert: Clusterfuzz unhappy: chromium:783019 chromium:783035

Original change's description:
> Reland^5 "[turbofan] eagerly prune None types and deadness from the graph"
>
> This gives up on earlier attempts to interpret DeadValue as a signal of
> unreachable code. This does not work because free-floating dead value
> nodes, and even pure branch nodes that use them, can get scheduled so
> early that they get reachable. Instead, we now eagerly remove branches
> that use DeadValue in DeadCodeElimination and replace DeadValue inputs
> to value phi nodes with dummy values.
>
> Reland of https://chromium-review.googlesource.com/715716
>
> Bug: chromium:741225 chromium:776256
> Change-Id: I251efd507c967d4a8882ad8fd2fd96c4185781fe
> Reviewed-on: https://chromium-review.googlesource.com/727893
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49188}

TBR=jarin@chromium.org,tebbi@chromium.org

Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
Change-Id: I6a8fa3a08ce2824a858ae01817688e63ed1f442e
Reviewed-on: https://chromium-review.googlesource.com/758770Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49262}
      c899637d
  29. 07 Nov, 2017 1 commit
  31. 19 Oct, 2017 1 commit
    • Tobias Tebbi's avatar
      Revert "Reland^4 "[turbofan] eagerly prune None types and deadness from the graph"" · 2bf01995
      Tobias Tebbi authored 
      This revert is manual, but almost completely automatic. 
It was just blocked by a single-line irrelevant refactoring change.
This reverts commit 1cee0e01.

Reason for revert: chromium:776256

Original change's description:
> Reland^4 "[turbofan] eagerly prune None types and deadness from the graph"
>
> This fixes https://bugs.chromium.org/p/chromium/issues/detail?id=773954.
> The issue was that in the EffectControlLinearizer, the effect input of an
> {Unreachable} node was not updated, leaving a {Checkpoint} behind.
>
> This is a reland of 4cf47645
> Original change's description:
> > Reland^3 "[turbofan] eagerly prune None types and deadness from the graph"
> >
> > This fixes the issues
> > https://bugs.chromium.org/p/chromium/issues/detail?id=772873
> > and https://bugs.chromium.org/p/chromium/issues/detail?id=772872.
> >
> > One problem was that mutating an effect node into Unreachable confused
> > the LoadElimination sidetables, so I just always create a new node now.
> >
> > The other problem was that UpdateBlockControl() was executed after
> > UpdateEffectPhi() in the lazy case. This reverted the update to the Merge input.
> > So now I make sure that UpdateEffectPhi() is always executed last.
> >
> > This is a reland of 6ddb5e7d
> > Original change's description:
> > > Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"
> > >
> > > Now, the EffectControlLinearizer connects all occurrences of Unreachable to the
> > > graph end. This fixes issues with later phases running DeadCodeElimination and
> > > introducing new DeadValue nodes when processing uses of Unreachable.
> > >
> > > This is a reland of 3c4bc27f
> > > Original change's description:
> > > > Reland "[turbofan] eagerly prune None types and deadness from the graph"
> > > >
> > > > This is a reland of e1cdda25
> > > > Original change's description:
> > > > > [turbofan] eagerly prune None types and deadness from the graph
> > > > >
> > > > > In addition to using the {Dead} node to prune dead control nodes and nodes that
> > > > > depend on them, we introduce a {DeadValue} node representing an impossible value
> > > > > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > > > > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > > > > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > > > > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > > > > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > > > > of a node with type {None} as dead.
> > > > >
> > > > > Bug: chromium:741225
> > > > > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > > > > Reviewed-on: https://chromium-review.googlesource.com/641250
> > > > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > > > Cr-Commit-Position: refs/heads/master@{#48208}
> > > >
> > > > Bug: chromium:741225
> > > > Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> > > > Reviewed-on: https://chromium-review.googlesource.com/692034
> > > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > > Cr-Commit-Position: refs/heads/master@{#48232}
> > >
> > > Bug: chromium:741225
> > > Change-Id: I5702ec34856c075717162153adc765774453c45f
> > > Reviewed-on: https://chromium-review.googlesource.com/702264
> > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#48366}
> >
> > Bug: chromium:741225
> > Change-Id: I4054a694d2521c2e1f0c4a3ad0f3cf100b5c536f
> > Reviewed-on: https://chromium-review.googlesource.com/709214
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48469}
>
> Bug: chromium:741225
> Change-Id: Id9d4f3a3ae36cb3e38f80edcdba88efa7922ca24
> Reviewed-on: https://chromium-review.googlesource.com/715716
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48660}

TBR=jarin@chromium.org,tebbi@chromium.org,bmeurer@chromium.org


Bug: chromium:741225 chromium:776256
Change-Id: Iaf2af3cb6dea5fdece43297cb9d987e7decc726d
Reviewed-on: https://chromium-review.googlesource.com/727804
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48749}
      2bf01995
  33. 18 Oct, 2017 1 commit
    • Tobias Tebbi's avatar
      Reland^4 "[turbofan] eagerly prune None types and deadness from the graph" · 1cee0e01
      Tobias Tebbi authored 
      This fixes https://bugs.chromium.org/p/chromium/issues/detail?id=773954.
The issue was that in the EffectControlLinearizer, the effect input of an
{Unreachable} node was not updated, leaving a {Checkpoint} behind.

This is a reland of 4cf47645
Original change's description:
> Reland^3 "[turbofan] eagerly prune None types and deadness from the graph"
> 
> This fixes the issues 
> https://bugs.chromium.org/p/chromium/issues/detail?id=772873 
> and https://bugs.chromium.org/p/chromium/issues/detail?id=772872.
> 
> One problem was that mutating an effect node into Unreachable confused 
> the LoadElimination sidetables, so I just always create a new node now.
> 
> The other problem was that UpdateBlockControl() was executed after 
> UpdateEffectPhi() in the lazy case. This reverted the update to the Merge input.
> So now I make sure that UpdateEffectPhi() is always executed last.
> 
> This is a reland of 6ddb5e7d
> Original change's description:
> > Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"
> > 
> > Now, the EffectControlLinearizer connects all occurrences of Unreachable to the 
> > graph end. This fixes issues with later phases running DeadCodeElimination and
> > introducing new DeadValue nodes when processing uses of Unreachable.
> > 
> > This is a reland of 3c4bc27f
> > Original change's description:
> > > Reland "[turbofan] eagerly prune None types and deadness from the graph"
> > > 
> > > This is a reland of e1cdda25
> > > Original change's description:
> > > > [turbofan] eagerly prune None types and deadness from the graph
> > > > 
> > > > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > > > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > > > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > > > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > > > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > > > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > > > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > > > of a node with type {None} as dead.
> > > > 
> > > > Bug: chromium:741225
> > > > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > > > Reviewed-on: https://chromium-review.googlesource.com/641250
> > > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > > Cr-Commit-Position: refs/heads/master@{#48208}
> > > 
> > > Bug: chromium:741225
> > > Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> > > Reviewed-on: https://chromium-review.googlesource.com/692034
> > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#48232}
> > 
> > Bug: chromium:741225
> > Change-Id: I5702ec34856c075717162153adc765774453c45f
> > Reviewed-on: https://chromium-review.googlesource.com/702264
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48366}
> 
> Bug: chromium:741225
> Change-Id: I4054a694d2521c2e1f0c4a3ad0f3cf100b5c536f
> Reviewed-on: https://chromium-review.googlesource.com/709214
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48469}

Bug: chromium:741225
Change-Id: Id9d4f3a3ae36cb3e38f80edcdba88efa7922ca24
Reviewed-on: https://chromium-review.googlesource.com/715716Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48660}
      1cee0e01
  35. 13 Oct, 2017 1 commit
  37. 12 Oct, 2017 1 commit
    • Benedikt Meurer's avatar
      Revert "Reland^3 "[turbofan] eagerly prune None types and deadness from the graph"" · e29fd74c
      Benedikt Meurer authored 
      This reverts commit 4cf47645.

Reason for revert: Broken effect chains detected by Clusterfuzz. Playing it safe for the 63 branch.

Original change's description:
> Reland^3 "[turbofan] eagerly prune None types and deadness from the graph"
> 
> This fixes the issues 
> https://bugs.chromium.org/p/chromium/issues/detail?id=772873 
> and https://bugs.chromium.org/p/chromium/issues/detail?id=772872.
> 
> One problem was that mutating an effect node into Unreachable confused 
> the LoadElimination sidetables, so I just always create a new node now.
> 
> The other problem was that UpdateBlockControl() was executed after 
> UpdateEffectPhi() in the lazy case. This reverted the update to the Merge input.
> So now I make sure that UpdateEffectPhi() is always executed last.
> 
> This is a reland of 6ddb5e7d
> Original change's description:
> > Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"
> > 
> > Now, the EffectControlLinearizer connects all occurrences of Unreachable to the 
> > graph end. This fixes issues with later phases running DeadCodeElimination and
> > introducing new DeadValue nodes when processing uses of Unreachable.
> > 
> > This is a reland of 3c4bc27f
> > Original change's description:
> > > Reland "[turbofan] eagerly prune None types and deadness from the graph"
> > > 
> > > This is a reland of e1cdda25
> > > Original change's description:
> > > > [turbofan] eagerly prune None types and deadness from the graph
> > > > 
> > > > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > > > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > > > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > > > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > > > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > > > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > > > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > > > of a node with type {None} as dead.
> > > > 
> > > > Bug: chromium:741225
> > > > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > > > Reviewed-on: https://chromium-review.googlesource.com/641250
> > > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > > Cr-Commit-Position: refs/heads/master@{#48208}
> > > 
> > > Bug: chromium:741225
> > > Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> > > Reviewed-on: https://chromium-review.googlesource.com/692034
> > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#48232}
> > 
> > Bug: chromium:741225
> > Change-Id: I5702ec34856c075717162153adc765774453c45f
> > Reviewed-on: https://chromium-review.googlesource.com/702264
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48366}
> 
> Bug: chromium:741225
> Change-Id: I4054a694d2521c2e1f0c4a3ad0f3cf100b5c536f
> Reviewed-on: https://chromium-review.googlesource.com/709214
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48469}

TBR=jarin@chromium.org,tebbi@chromium.org

Change-Id: Icf6a6af4feaafd4bde28cb7b996735ff91bb3810
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:741225
Reviewed-on: https://chromium-review.googlesource.com/715096Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48482}
      e29fd74c
  39. 11 Oct, 2017 1 commit
    • Tobias Tebbi's avatar
      Reland^3 "[turbofan] eagerly prune None types and deadness from the graph" · 4cf47645
      Tobias Tebbi authored 
      This fixes the issues 
https://bugs.chromium.org/p/chromium/issues/detail?id=772873 
and https://bugs.chromium.org/p/chromium/issues/detail?id=772872.

One problem was that mutating an effect node into Unreachable confused 
the LoadElimination sidetables, so I just always create a new node now.

The other problem was that UpdateBlockControl() was executed after 
UpdateEffectPhi() in the lazy case. This reverted the update to the Merge input.
So now I make sure that UpdateEffectPhi() is always executed last.

This is a reland of 6ddb5e7d
Original change's description:
> Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"
> 
> Now, the EffectControlLinearizer connects all occurrences of Unreachable to the 
> graph end. This fixes issues with later phases running DeadCodeElimination and
> introducing new DeadValue nodes when processing uses of Unreachable.
> 
> This is a reland of 3c4bc27f
> Original change's description:
> > Reland "[turbofan] eagerly prune None types and deadness from the graph"
> > 
> > This is a reland of e1cdda25
> > Original change's description:
> > > [turbofan] eagerly prune None types and deadness from the graph
> > > 
> > > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > > of a node with type {None} as dead.
> > > 
> > > Bug: chromium:741225
> > > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > > Reviewed-on: https://chromium-review.googlesource.com/641250
> > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#48208}
> > 
> > Bug: chromium:741225
> > Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> > Reviewed-on: https://chromium-review.googlesource.com/692034
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48232}
> 
> Bug: chromium:741225
> Change-Id: I5702ec34856c075717162153adc765774453c45f
> Reviewed-on: https://chromium-review.googlesource.com/702264
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48366}

Bug: chromium:741225
Change-Id: I4054a694d2521c2e1f0c4a3ad0f3cf100b5c536f
Reviewed-on: https://chromium-review.googlesource.com/709214
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48469}
      4cf47645
  41. 09 Oct, 2017 2 commits
    • Tobias Tebbi's avatar
      Revert "Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"" · 738e773b
      Tobias Tebbi authored 
      This reverts commit 6ddb5e7d.

Reason for revert: chromium:772873 chromium:772872

Original change's description:
> Reland^2 "[turbofan] eagerly prune None types and deadness from the graph"
> 
> Now, the EffectControlLinearizer connects all occurrences of Unreachable to the 
> graph end. This fixes issues with later phases running DeadCodeElimination and
> introducing new DeadValue nodes when processing uses of Unreachable.
> 
> This is a reland of 3c4bc27f
> Original change's description:
> > Reland "[turbofan] eagerly prune None types and deadness from the graph"
> > 
> > This is a reland of e1cdda25
> > Original change's description:
> > > [turbofan] eagerly prune None types and deadness from the graph
> > > 
> > > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > > of a node with type {None} as dead.
> > > 
> > > Bug: chromium:741225
> > > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > > Reviewed-on: https://chromium-review.googlesource.com/641250
> > > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#48208}
> > 
> > Bug: chromium:741225
> > Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> > Reviewed-on: https://chromium-review.googlesource.com/692034
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48232}
> 
> Bug: chromium:741225
> Change-Id: I5702ec34856c075717162153adc765774453c45f
> Reviewed-on: https://chromium-review.googlesource.com/702264
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48366}

TBR=jarin@chromium.org,tebbi@chromium.org

Change-Id: Ib0f59b8463681abf6a9158112515aefae3c76b5f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:741225
Reviewed-on: https://chromium-review.googlesource.com/707275Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48407}
      738e773b
    • Tobias Tebbi's avatar
      Reland^2 "[turbofan] eagerly prune None types and deadness from the graph" · 6ddb5e7d
      Tobias Tebbi authored 
      Now, the EffectControlLinearizer connects all occurrences of Unreachable to the 
graph end. This fixes issues with later phases running DeadCodeElimination and
introducing new DeadValue nodes when processing uses of Unreachable.

This is a reland of 3c4bc27f
Original change's description:
> Reland "[turbofan] eagerly prune None types and deadness from the graph"
> 
> This is a reland of e1cdda25
> Original change's description:
> > [turbofan] eagerly prune None types and deadness from the graph
> > 
> > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > of a node with type {None} as dead.
> > 
> > Bug: chromium:741225
> > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > Reviewed-on: https://chromium-review.googlesource.com/641250
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48208}
> 
> Bug: chromium:741225
> Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> Reviewed-on: https://chromium-review.googlesource.com/692034
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48232}

Bug: chromium:741225
Change-Id: I5702ec34856c075717162153adc765774453c45f
Reviewed-on: https://chromium-review.googlesource.com/702264Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48366}
      6ddb5e7d
  43. 30 Sep, 2017 1 commit
    • Tobias Tebbi's avatar
      Revert "Reland "[turbofan] eagerly prune None types and deadness from the graph"" · 4651f644
      Tobias Tebbi authored 
      This reverts commit 3c4bc27f.

Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=770257

Original change's description:
> Reland "[turbofan] eagerly prune None types and deadness from the graph"
> 
> This is a reland of e1cdda25
> Original change's description:
> > [turbofan] eagerly prune None types and deadness from the graph
> > 
> > In addition to using the {Dead} node to prune dead control nodes and nodes that 
> > depend on them, we introduce a {DeadValue} node representing an impossible value 
> > that can occur at any position in the graph. The extended {DeadCodeElimination}
> > prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> > the effect chain when possible. The remaining uses of {DeadValue} are handled
> > in {EffectControlLinearizer}, where we always have access to the effect chain.
> > In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> > of a node with type {None} as dead.
> > 
> > Bug: chromium:741225
> > Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> > Reviewed-on: https://chromium-review.googlesource.com/641250
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48208}
> 
> Bug: chromium:741225
> Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
> Reviewed-on: https://chromium-review.googlesource.com/692034
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48232}

TBR=jarin@chromium.org,tebbi@chromium.org

Change-Id: Ied8da411a9c8cbe4ed2e1d3e98a76162c2834c97
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:741225 chromium:770257
Reviewed-on: https://chromium-review.googlesource.com/693235Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48246}
      4651f644
  45. 29 Sep, 2017 1 commit
    • Tobias Tebbi's avatar
      Reland "[turbofan] eagerly prune None types and deadness from the graph" · 3c4bc27f
      Tobias Tebbi authored 
      This is a reland of e1cdda25
Original change's description:
> [turbofan] eagerly prune None types and deadness from the graph
> 
> In addition to using the {Dead} node to prune dead control nodes and nodes that 
> depend on them, we introduce a {DeadValue} node representing an impossible value 
> that can occur at any position in the graph. The extended {DeadCodeElimination}
> prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> the effect chain when possible. The remaining uses of {DeadValue} are handled
> in {EffectControlLinearizer}, where we always have access to the effect chain.
> In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> of a node with type {None} as dead.
> 
> Bug: chromium:741225
> Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> Reviewed-on: https://chromium-review.googlesource.com/641250
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48208}

Bug: chromium:741225
Change-Id: I21316913dae02864f7a6d7c9269405a79f054138
Reviewed-on: https://chromium-review.googlesource.com/692034Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48232}
      3c4bc27f
  47. 28 Sep, 2017 2 commits
    • Clemens Hammacher's avatar
      Revert "[turbofan] eagerly prune None types and deadness from the graph" · 324e0a7a
      Clemens Hammacher authored 
      This reverts commit e1cdda25.

Reason for revert: Fails 'constructor-inlining' on GC-Stress bot: https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/builds/15270

Original change's description:
> [turbofan] eagerly prune None types and deadness from the graph
> 
> In addition to using the {Dead} node to prune dead control nodes and nodes that 
> depend on them, we introduce a {DeadValue} node representing an impossible value 
> that can occur at any position in the graph. The extended {DeadCodeElimination}
> prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
> the effect chain when possible. The remaining uses of {DeadValue} are handled
> in {EffectControlLinearizer}, where we always have access to the effect chain.
> In addition to explicitly introduced {DeadValue} nodes, we consider any value use
> of a node with type {None} as dead.
> 
> Bug: chromium:741225
> Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
> Reviewed-on: https://chromium-review.googlesource.com/641250
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48208}

TBR=jarin@chromium.org,tebbi@chromium.org

Change-Id: I9c175d47e2ee4b11a36ed90421202f2354610398
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:741225
Reviewed-on: https://chromium-review.googlesource.com/690080Reviewed-by: 's avatarClemens Hammacher <clemensh@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48210}
      324e0a7a
    • Tobias Tebbi's avatar
      [turbofan] eagerly prune None types and deadness from the graph · e1cdda25
      Tobias Tebbi authored 
      In addition to using the {Dead} node to prune dead control nodes and nodes that 
depend on them, we introduce a {DeadValue} node representing an impossible value 
that can occur at any position in the graph. The extended {DeadCodeElimination}
prunes {DeadValue} and its uses, inserting a crashing {Unreachable} node into
the effect chain when possible. The remaining uses of {DeadValue} are handled
in {EffectControlLinearizer}, where we always have access to the effect chain.
In addition to explicitly introduced {DeadValue} nodes, we consider any value use
of a node with type {None} as dead.

Bug: chromium:741225
Change-Id: Icc4b636d1d018c452ba1a2fa7cd3e00e522f1655
Reviewed-on: https://chromium-review.googlesource.com/641250
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48208}
      e1cdda25
  49. 11 Jul, 2017 1 commit
  51. 10 Jul, 2017 2 commits
    • Benedikt Meurer's avatar
      [turbofan] Widen the fast-path for JSCreateArray. · 1edb46cc
      Benedikt Meurer authored 
      This improves the general Array constructor call performance (w/o
usable AllocationSite feedback) in TurboFan by ~2x, i.e. for example
invoking the Array constructor like this

  var a = Array.call(undefined, n);

instead of

  var a = Array(n);

such that the CallIC doesn't know that it's eventually calling the
Array constructor.

It also thus changes the single argument Array constructor to always
return holey arrays. Previously the single argument case for the Array
constructor was somehow trying to dynamically detect 0 and in that case
returned a packed array instead of a holey one. That adds quite a lot
of churn, and doesn't seem to be very useful, especially since this
might lead to unnecessary feedback pollution later.

R=mvstanton@chromium.org

Bug: v8:2229, v8:5269, v8:6399
Change-Id: I3d7cb9bd975ec0e491e3cdbcf1230185cfd1e3de
Reviewed-on: https://chromium-review.googlesource.com/565721Reviewed-by: 's avatarMichael Stanton <mvstanton@chromium.org>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46538}
      1edb46cc
    • Jaroslav Sevcik's avatar
      Initial optimization of Map.prototype.(get|has) in Turbofan. · aba708a1
      Jaroslav Sevcik authored 
      This introduces a new builtin (MapLookupHashIndex) and uses it
in Turbofan to compute Map.p.get and Map.p.has.

I have also refactored the existing CSA builtins for Map.p.get and 
Map.p.has to use the new builtin under the hood.

The code for the lookup has been also improved.
- Specialized lookups for smis, strings, heap numbers and everything else.
  - the advantage is that we can use fast equalities for the lookup.
  - strings can likely be optimized further if we care about the 
    internalized string fast case.
- Instead of a call to runtime to get the hash code, we now call C directly.

In the Turbofan implementation itself, there are no special optimizations yet.
The next step is to teach load elimination to reuse the indexes from
previous calls of MapLookupHashIndex. 

BUG=v8:6410

Change-Id: I0b1a70493eb031d444e51002f6b2cc1f30ea2b68
Reviewed-on: https://chromium-review.googlesource.com/560169Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46510}
      aba708a1
  53. 04 May, 2017 1 commit
  55. 06 Feb, 2017 1 commit
    • mvstanton's avatar
      [TypeFeedbackVector] Root feedback vectors at function literal site. · aea3ce3d
      mvstanton authored 
      TypeFeedbackVectors are strongly rooted by a closure. However, in modern
JavaScript closures are created and abandoned more freely. An important
closure may not be present in the root-set at time of garbage collection,
even though we've cached optimized code and use it regularly. For
example, consider leaf functions in an event dispatching system. They may
well be "hot," but tragically non-present when we collect the heap.

Until now, we've relied on a weak root to cache the feedback vector in
this case. Since there is no way to signal intent or relative importance,
this weak root is as susceptible to clearing as any other weak root at
garbage collection time.

Meanwhile, the feedback vector has become more important. All of our
ICs store their data there. Literal and regex boilerplates are stored there.
If we lose the vector, then we not only lose optimized code built from
it, we also lose the very feedback which allowed us to create that optimized
code. Therefore it's vital to express that dependency through the root
set.

This CL does this by creating a strong link to a feedback
vector at the instantiation site of the function closure.
This instantiation site is in the code and feedback vector
of the outer closure.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2674593003
Cr-Commit-Position: refs/heads/master@{#42953}
      aea3ce3d
  57. 30 Jan, 2017 1 commit
    • mvstanton's avatar
      [TypeFeedbackVector] Combine the literals array and the feedback vector. · 93f05b64
      mvstanton authored 
      They have the same lifetime. It's a match!

Both structures are native context dependent and dealt with (creation,
clearing, gathering feedback) at the same time. By treating the spaces used
for literal boilerplates as feedback vector slots, we no longer have to keep
track of the materialized literal count elsewhere.

A follow-on CL removes even more parser infrastructure related to this count.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2655853010
Cr-Commit-Position: refs/heads/master@{#42771}
      93f05b64
  59. 19 Jan, 2017 3 commits
  61. 12 Jan, 2017 3 commits
  63. 30 Dec, 2016 1 commit