1 /* 2 * Copyright (C) 2008, 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 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef EvalCodeCache_h 30 #define EvalCodeCache_h 31 32 #include "Executable.h" 33 #include "JSGlobalObject.h" 34 #include "Nodes.h" 35 #include "Parser.h" 36 #include "SourceCode.h" 37 #include "UString.h" 38 #include <wtf/HashMap.h> 39 #include <wtf/RefPtr.h> 40 #include <wtf/text/StringHash.h> 41 42 namespace JSC { 43 44 class MarkStack; 45 46 class EvalCodeCache { 47 public: 48 EvalExecutable* get(ExecState* exec, ScriptExecutable* owner, bool inStrictContext, const UString& evalSource, ScopeChainNode* scopeChain, JSValue& exceptionValue) 49 { 50 EvalExecutable* evalExecutable = 0; 51 52 if (!inStrictContext && evalSource.length() < maxCacheableSourceLength && (*scopeChain->begin())->isVariableObject()) 53 evalExecutable = m_cacheMap.get(evalSource.impl()).get(); 54 55 if (!evalExecutable) { 56 evalExecutable = EvalExecutable::create(exec, makeSource(evalSource), inStrictContext); 57 exceptionValue = evalExecutable->compile(exec, scopeChain); 58 if (exceptionValue) 59 return 0; 60 61 if (!inStrictContext && evalSource.length() < maxCacheableSourceLength && (*scopeChain->begin())->isVariableObject() && m_cacheMap.size() < maxCacheEntries) 62 m_cacheMap.set(evalSource.impl(), WriteBarrier<EvalExecutable>(exec->globalData(), owner, evalExecutable)); 63 } 64 65 return evalExecutable; 66 } 67 68 bool isEmpty() const { return m_cacheMap.isEmpty(); } 69 70 void markAggregate(MarkStack&); 71 72 private: 73 static const unsigned maxCacheableSourceLength = 256; 74 static const int maxCacheEntries = 64; 75 76 typedef HashMap<RefPtr<StringImpl>, WriteBarrier<EvalExecutable> > EvalCacheMap; 77 EvalCacheMap m_cacheMap; 78 }; 79 80 } // namespace JSC 81 82 #endif // EvalCodeCache_h 83
