v8/test/mjsunit/regress/regress-5660.js
Nico Hartmann 120d433345 Reland "[turbofan] Improve equality on NumberOrOddball"
This is a reland of 6204768bab

The original issue exposed the problem that NumberEqual performs
implicit conversion of oddballs to numbers, which is incorrect for
abstract equality comparison (i.e. 0 == null must not be true).

This reland fixes this by applying the following steps:
* Introduced a new kNumberOrBoolean value for CompareOperationFeedback,
  CompareOperationHint, TypeCheckKind and CheckedTaggedInputMode.
* In CodeStubAssembler::Equal: Further distinguish between boolean and
  non-boolean oddballs and set feedback accoringly.
* In JSTypedLowering: Construct [Speculative]NumberEqual operator with
  CompareOperationHint::kNumberOrBoolean, when this feedback is present.
  JSOperatorBuilder and operator cache are extended accordingly.
* In SimplifiedLowering: Propagate a UseInfo with new
  TypeCheckKind::kNumberOrBoolean.
* This leads to the generation of CheckedTaggedToFloat64 in
  RepresentationChanger with new CheckedTaggedInputMode::kNumberOrBoolean.
* In EffectControlLinearizer: Handle this new mode. Accept and convert
  number and boolean and deopt for rest.

Original change's description:
> [turbofan] Improve equality on NumberOrOddball
>
> This CL cleans up CompareOperationFeedback by replacing it with a
> composable set of flags. The interpreter is changed to collect
> more specific feedback for abstract equality, especially if oddballs
> are involved.
>
> TurboFan is changed to construct SpeculativeNumberEqual operator
> instead of the generic JSEqual in many more cases. This change has
> shown a local speedup of a factor of 3-10, because the specific
> operator is way faster than calling into the generic builtin, but
> it also enables additional optimizations, further improving
> runtime performance.
>
> Bug: v8:5660
> Change-Id: I856752caa707e9a4f742c6e7a9c75552fb431d28
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2162854
> Reviewed-by: Mythri Alle <mythria@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67645}

TBR: tebbi@chromium.org
Bug: v8:5660
Change-Id: I12e733149a1d2773cafb781a1d4b10aa1eb242a7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2193713
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68037}
2020-05-28 11:33:46 +00:00

42 lines
965 B
JavaScript

// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --opt --allow-natives-syntax
(function() {
function test(a, b) {
return a === b;
}
%PrepareFunctionForOptimization(test);
assertTrue(test(undefined, undefined));
assertTrue(test(undefined, undefined));
%OptimizeFunctionOnNextCall(test);
assertTrue(test(undefined, undefined));
})();
(function() {
function test(a, b) {
return a === b;
}
%PrepareFunctionForOptimization(test);
assertTrue(test(true, true));
assertTrue(test(true, true));
%OptimizeFunctionOnNextCall(test);
assertFalse(test(true, 1));
})();
(function() {
function test(a, b) {
return a == b;
}
%PrepareFunctionForOptimization(test);
assertTrue(test(true, true));
assertTrue(test(true, true));
%OptimizeFunctionOnNextCall(test);
assertTrue(test(true, 1));
})();