v8/test/mjsunit/compiler/function-bind.js
bmeurer 3028f8075e [turbofan] Optimize Function.prototype.bind for the common case.
When the input to Function.prototype.bind is a known function, we can
inline the allocation of the JSBoundFunction into TurboFan, which
provides a 2x speed-up for several hot functions in Node streams (as
discovered by Matteo Collina). One of example of this can be found in
https://github.com/nodejs/node/pull/13322, which can be optimized and
made more readable using bind instead of closures.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2916063002
Cr-Commit-Position: refs/heads/master@{#45679}
2017-06-02 12:30:04 +00:00

78 lines
1.6 KiB
JavaScript

// Copyright 2017 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() {
"use strict";
function bar() { return this; }
function foo(x) {
return bar.bind(x);
}
assertEquals(0, foo(0)());
assertEquals(1, foo(1)());
%OptimizeFunctionOnNextCall(foo);
assertEquals("", foo("")());
})();
(function() {
"use strict";
function bar(x) { return x; }
function foo(x) {
return bar.bind(undefined, x);
}
assertEquals(0, foo(0)());
assertEquals(1, foo(1)());
%OptimizeFunctionOnNextCall(foo);
assertEquals("", foo("")());
})();
(function() {
function bar(x) { return x; }
function foo(x) {
return bar.bind(undefined, x);
}
assertEquals(0, foo(0)());
assertEquals(1, foo(1)());
%OptimizeFunctionOnNextCall(foo);
assertEquals("", foo("")());
})();
(function() {
"use strict";
function bar(x, y) { return x + y; }
function foo(x, y) {
return bar.bind(undefined, x, y);
}
assertEquals(0, foo(0, 0)());
assertEquals(2, foo(1, 1)());
%OptimizeFunctionOnNextCall(foo);
assertEquals("ab", foo("a", "b")());
assertEquals(0, foo(0, 1).length);
assertEquals("bound bar", foo(1, 2).name)
})();
(function() {
function bar(x, y) { return x + y; }
function foo(x, y) {
return bar.bind(undefined, x, y);
}
assertEquals(0, foo(0, 0)());
assertEquals(2, foo(1, 1)());
%OptimizeFunctionOnNextCall(foo);
assertEquals("ab", foo("a", "b")());
assertEquals(0, foo(0, 1).length);
assertEquals("bound bar", foo(1, 2).name)
})();