v8/test/mjsunit/array-literal-feedback.js
Camillo Bruni 015edc60ff [runtime] Don't store object literal boilerplates on first run
Storing the boilerplate on the first run leads to memory ovehead for code
that is run only once. Hence we directly return the creating literal on the
first run and only start creating copies from the second run on.

Bug: v8:6211
Change-Id: I69b96d124a5b594b991fdbcc76dbf935d973ffad
Reviewed-on: https://chromium-review.googlesource.com/530688
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45975}
2017-06-16 10:43:19 +00:00

119 lines
4.3 KiB
JavaScript

// Copyright 2013 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.
// Flags: --allow-natives-syntax --expose-gc
// Flags: --opt --no-always-opt
var elements_kind = {
fast_smi_only : 'fast smi only elements',
fast : 'fast elements',
fast_double : 'fast double elements',
dictionary : 'dictionary elements',
external_byte : 'external byte elements',
external_unsigned_byte : 'external unsigned byte elements',
external_short : 'external short elements',
external_unsigned_short : 'external unsigned short elements',
external_int : 'external int elements',
external_unsigned_int : 'external unsigned int elements',
external_float : 'external float elements',
external_double : 'external double elements',
external_pixel : 'external pixel elements'
}
function getKind(obj) {
if (%HasFastSmiElements(obj)) return elements_kind.fast_smi_only;
if (%HasFastObjectElements(obj)) return elements_kind.fast;
if (%HasFastDoubleElements(obj)) return elements_kind.fast_double;
if (%HasDictionaryElements(obj)) return elements_kind.dictionary;
}
function isHoley(obj) {
if (%HasFastHoleyElements(obj)) return true;
return false;
}
function assertKind(expected, obj, name_opt) {
assertEquals(expected, getKind(obj), name_opt);
}
function get_literal(x) {
var literal = [1, 2, x];
return literal;
}
get_literal(3);
// It's important to store a from before we crankshaft get_literal, because
// mementos won't be created from crankshafted code at all.
a = get_literal(3);
%OptimizeFunctionOnNextCall(get_literal);
get_literal(3);
assertOptimized(get_literal);
assertTrue(%HasFastSmiElements(a));
// a has a memento so the transition caused by the store will affect the
// boilerplate.
a[0] = 3.5;
// We should have transitioned the boilerplate array to double, and
// crankshafted code should de-opt on the unexpected elements kind
b = get_literal(3);
assertTrue(%HasFastDoubleElements(b));
assertEquals([1, 2, 3], b);
assertUnoptimized(get_literal);
// Optimize again
get_literal(3);
%OptimizeFunctionOnNextCall(get_literal);
b = get_literal(3);
assertTrue(%HasFastDoubleElements(b));
assertOptimized(get_literal);
// Test: make sure allocation site information is updated through a
// transition from SMI->DOUBLE->FAST
(function() {
function bar(a, b, c) {
return [a, b, c];
}
var a = bar(1, 2, 3);
assertKind(elements_kind.fast_smi_only, a);
a[0] = 3.5;
a[1] = 'hi';
assertKind(elements_kind.fast, a);
// We only start tracking transition information with the second
// instantiation.
var b = bar(1, 2, 3);
assertKind(elements_kind.fast_smi_only, b);
b[0] = 3.5;
b[1] = 'hi';
assertKind(elements_kind.fast, b);
var c = bar(1, 2, 3);
assertKind(elements_kind.fast, c);
})();