v8/test/mjsunit/arguments-lazy.js
kasperl@chromium.org f66ea38c0b Allocate arguments object on-demand instead of at function entry.
This allows Function.prototype.apply to not allocate the objects 
and copy the arguments directly from the stack.
Review URL: http://codereview.chromium.org/147075

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2256 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2009-06-24 08:01:38 +00:00

48 lines
2.0 KiB
JavaScript

// Copyright 2009 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Make sure we don't allocate the arguments object over and
// over again.
function SharedLazyArguments() {
return arguments === arguments;
}
assertTrue(SharedLazyArguments());
// Make sure that accessing arguments doesn't clobber any
// local variables called arguments.
function ArgumentsOverride(x) {
var arguments = 42;
x = x ? x : 0;
return x + arguments;
}
assertEquals(42, ArgumentsOverride());
assertEquals(43, ArgumentsOverride(1));
assertEquals(44, ArgumentsOverride(2,3));