v8/test/mjsunit/regress/regress-460917.js
Mathias Bynens c6a16c10dd [test] Add %PrepareForOptimization to even more tests
With bytecode flushing and lazy feedback allocation, we need to call
%PrepareForOptimization before we call %OptimizeFunctionOnNextCall,
ideally after declaring the function.

Bug: v8:8801, v8:8394, v8:9183
Change-Id: I3fb257282a30f6526a376a3afdedb44786320d34
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1648255
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62119}
2019-06-12 14:40:14 +00:00

38 lines
1.1 KiB
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
function boom(a1, a2) {
// Do something with a2 that needs a map check (for DOUBLE_ELEMENTS).
var s = a2[0];
// Emit a load that transitions a1 to PACKED_ELEMENTS.
var t = a1[0];
// Emit a store to a2 that assumes DOUBLE_ELEMENTS.
// The map check is considered redundant and will be eliminated.
a2[0] = 0.3;
}
// Prepare type feedback for the "t = a1[0]" load: fast elements.
;
%PrepareFunctionForOptimization(boom);
var fast_elem = new Array(1);
fast_elem[0] = 'tagged';
boom(fast_elem, [1]);
// Prepare type feedback for the "a2[0] = 0.3" store: double elements.
var double_elem = new Array(1);
double_elem[0] = 0.1;
boom(double_elem, double_elem);
// Reset |double_elem| and go have a party.
double_elem = new Array(10);
double_elem[0] = 0.1;
%OptimizeFunctionOnNextCall(boom);
boom(double_elem, double_elem);
assertEquals(0.3, double_elem[0]);
assertEquals(undefined, double_elem[1]);