source: webkit/trunk/JavaScriptCore/runtime/JSByteArray.cpp@ 39625

Last change on this file since 39625 was 39625, checked in by [email protected], 16 years ago

CanvasPixelArray performance is too slow
<https://bugs.webkit.org/show_bug.cgi?id=23123>

Reviewed by Gavin Barraclough

JavaScriptCore:
The fix to this is to devirtualise get and put in a manner similar to
JSString and JSArray. To do this I've added a ByteArray implementation
and JSByteArray wrapper to JSC. We can then do vptr comparisons to
devirtualise the calls.

This devirtualisation improves performance by 1.5-2x in my somewhat ad
hoc tests.

WebCore:
Remove the WebCore CanvasPixelArray implementation and replace
CPA usage with JSC::ByteArray. Replace the JSCanvasPixelArray
wrapper with an explicitly instantiated JSByteArray put on the
JSImageData object as an ordinary ReadOnly, DontDelete property.

File size: 3.3 KB
Line 
1/*
2 * Copyright (C) 2009 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "JSByteArray.h"
28
29#include "JSGlobalObject.h"
30#include "PropertyNameArray.h"
31
32namespace JSC {
33
34const ClassInfo JSByteArray::s_defaultInfo = { "ByteArray", 0, 0, 0 };
35
36JSByteArray::JSByteArray(ExecState* exec, PassRefPtr<Structure> structure, ByteArray* storage, const JSC::ClassInfo* classInfo)
37 : JSObject(structure)
38 , m_storage(storage)
39 , m_classInfo(classInfo)
40{
41 putDirect(exec->globalData().propertyNames->length, jsNumber(exec, m_storage->length()), ReadOnly | DontDelete);
42}
43
44PassRefPtr<Structure> JSByteArray::createStructure(JSValue* prototype)
45{
46 PassRefPtr<Structure> result = Structure::create(prototype, TypeInfo(ObjectType));
47 return result;
48}
49
50bool JSByteArray::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
51{
52 bool ok;
53 unsigned index = propertyName.toUInt32(&ok, false);
54 if (ok && canAccessIndex(index)) {
55 slot.setValue(getIndex(index));
56 return true;
57 }
58 return JSObject::getOwnPropertySlot(exec, propertyName, slot);
59}
60
61bool JSByteArray::getOwnPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot)
62{
63 if (canAccessIndex(propertyName)) {
64 slot.setValue(getIndex(propertyName));
65 return true;
66 }
67 return JSObject::getOwnPropertySlot(exec, Identifier::from(exec, propertyName), slot);
68}
69
70void JSByteArray::put(ExecState* exec, const Identifier& propertyName, JSValue* value, PutPropertySlot& slot)
71{
72 bool ok;
73 unsigned index = propertyName.toUInt32(&ok, false);
74 if (ok) {
75 setIndex(exec, index, value);
76 return;
77 }
78 JSObject::put(exec, propertyName, value, slot);
79}
80
81void JSByteArray::put(ExecState* exec, unsigned propertyName, JSValue* value)
82{
83 setIndex(exec, propertyName, value);
84}
85
86void JSByteArray::getPropertyNames(ExecState* exec, PropertyNameArray& propertyNames)
87{
88 unsigned length = m_storage->length();
89 for (unsigned i = 0; i < length; ++i)
90 propertyNames.add(Identifier::from(exec, i));
91 JSObject::getPropertyNames(exec, propertyNames);
92}
93
94}
95
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