7709e41aec
Previously ChangeLowering would always box float64 values when going to tagged representation, but that introduces a lot of deoptimizer loops and polymorphism into TurboFan, which is unfortunate and unnecessary. This adds some logic to ChangeFloat64ToTagged to try harder to create a Smi when going from Float64 to Tagged, instead of always allocating a HeapNumber. This might need some additional tweaking, but at least it makes it possible to start comparing TurboFan and Crankshaft for some regular JavaScript. R=jarin@chromium.org Review URL: https://codereview.chromium.org/1420913003 Cr-Commit-Position: refs/heads/master@{#31609}
24 lines
651 B
JavaScript
24 lines
651 B
JavaScript
// Copyright 2015 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: --allow-natives-syntax
|
|
|
|
var doubles = new Float64Array(1);
|
|
function ToHeapNumber(i) {
|
|
doubles[0] = i;
|
|
return doubles[0];
|
|
}
|
|
for (var i = 0; i < 3; i++) ToHeapNumber(i);
|
|
%OptimizeFunctionOnNextCall(ToHeapNumber);
|
|
ToHeapNumber(1);
|
|
|
|
function Fail(a, i, v) {
|
|
a[i] = v;
|
|
}
|
|
|
|
for (var i = 0; i < 3; i++) Fail(new Array(1), 1, i);
|
|
%OptimizeFunctionOnNextCall(Fail);
|
|
// 1050 > JSObject::kMaxGap, causing stub failure and runtime call.
|
|
Fail(new Array(1), ToHeapNumber(1050), 3);
|