source: webkit/trunk/JavaScriptCore/runtime/JSGlobalData.h@ 58224

/*
 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer. 
 * 2.  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. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef JSGlobalData_h
#define JSGlobalData_h

#include "Collector.h"
#include "DateInstanceCache.h"
#include "ExecutableAllocator.h"
#include "JITStubs.h"
#include "JSValue.h"
#include "MarkStack.h"
#include "NumericStrings.h"
#include "SmallStrings.h"
#include "Terminator.h"
#include "TimeoutChecker.h"
#include "WeakRandom.h"
#include <wtf/Forward.h>
#include <wtf/HashMap.h>
#include <wtf/RefCounted.h>

struct OpaqueJSClass;
struct OpaqueJSClassContextData;

namespace JSC {

    class CodeBlock;
    class CommonIdentifiers;
    class IdentifierTable;
    class Interpreter;
    class JSGlobalObject;
    class JSObject;
    class Lexer;
    class LiteralTable;
    class Parser;
    class Stringifier;
    class Structure;
    class UString;

    struct HashTable;
    struct Instruction;    

    struct DSTOffsetCache {
        DSTOffsetCache()
        {
            reset();
        }
        
        void reset()
        {
            offset = 0.0;
            start = 0.0;
            end = -1.0;
            increment = 0.0;
        }

        double offset;
        double start;
        double end;
        double increment;
    };

    enum ThreadStackType {
        ThreadStackTypeLarge,
        ThreadStackTypeSmall
    };

    class JSGlobalData : public RefCounted<JSGlobalData> {
    public:
        // WebCore has a one-to-one mapping of threads to JSGlobalDatas;
        // either create() or createLeaked() should only be called once
        // on a thread, this is the 'default' JSGlobalData (it uses the
        // thread's default string uniquing table from wtfThreadData).
        // API contexts created using the new context group aware interface
        // create APIContextGroup objects which require less locking of JSC
        // than the old singleton APIShared JSGlobalData created for use by
        // the original API.
        enum GlobalDataType { Default, APIContextGroup, APIShared };

        struct ClientData {
            virtual ~ClientData() = 0;
        };

        bool isSharedInstance() { return globalDataType == APIShared; }
        static bool sharedInstanceExists();
        static JSGlobalData& sharedInstance();

        static PassRefPtr<JSGlobalData> create(ThreadStackType);
        static PassRefPtr<JSGlobalData> createLeaked(ThreadStackType);
        static PassRefPtr<JSGlobalData> createContextGroup(ThreadStackType);
        ~JSGlobalData();

#if ENABLE(JSC_MULTIPLE_THREADS)
        // Will start tracking threads that use the heap, which is resource-heavy.
        void makeUsableFromMultipleThreads() { heap.makeUsableFromMultipleThreads(); }
#endif

        GlobalDataType globalDataType;
        ClientData* clientData;

        const HashTable* arrayTable;
        const HashTable* dateTable;
        const HashTable* jsonTable;
        const HashTable* mathTable;
        const HashTable* numberTable;
        const HashTable* regExpTable;
        const HashTable* regExpConstructorTable;
        const HashTable* stringTable;
        
        RefPtr<Structure> activationStructure;
        RefPtr<Structure> interruptedExecutionErrorStructure;
        RefPtr<Structure> terminatedExecutionErrorStructure;
        RefPtr<Structure> staticScopeStructure;
        RefPtr<Structure> stringStructure;
        RefPtr<Structure> notAnObjectErrorStubStructure;
        RefPtr<Structure> notAnObjectStructure;
        RefPtr<Structure> propertyNameIteratorStructure;
        RefPtr<Structure> getterSetterStructure;
        RefPtr<Structure> apiWrapperStructure;
        RefPtr<Structure> dummyMarkableCellStructure;

#if USE(JSVALUE32)
        RefPtr<Structure> numberStructure;
#endif

        static void storeVPtrs();
        static JS_EXPORTDATA void* jsArrayVPtr;
        static JS_EXPORTDATA void* jsByteArrayVPtr;
        static JS_EXPORTDATA void* jsStringVPtr;
        static JS_EXPORTDATA void* jsFunctionVPtr;

        IdentifierTable* identifierTable;
        LiteralTable* literalTable;
        CommonIdentifiers* propertyNames;
        const MarkedArgumentBuffer* emptyList; // Lists are supposed to be allocated on the stack to have their elements properly marked, which is not the case here - but this list has nothing to mark.
        SmallStrings smallStrings;
        NumericStrings numericStrings;
        DateInstanceCache dateInstanceCache;
        
#if ENABLE(ASSEMBLER)
        ExecutableAllocator executableAllocator;
#endif

        Lexer* lexer;
        Parser* parser;
        Interpreter* interpreter;
#if ENABLE(JIT)
        JITThunks jitStubs;
#endif
        TimeoutChecker timeoutChecker;
        Terminator terminator;
        Heap heap;

        JSValue exception;
#if ENABLE(JIT)
        ReturnAddressPtr exceptionLocation;
#endif

        const Vector<Instruction>& numericCompareFunction(ExecState*);
        Vector<Instruction> lazyNumericCompareFunction;
        bool initializingLazyNumericCompareFunction;

        HashMap<OpaqueJSClass*, OpaqueJSClassContextData*> opaqueJSClassData;

        JSGlobalObject* head;
        JSGlobalObject* dynamicGlobalObject;

        HashSet<JSObject*> arrayVisitedElements;

        CodeBlock* functionCodeBlockBeingReparsed;
        Stringifier* firstStringifierToMark;

        MarkStack markStack;

        double cachedUTCOffset;
        DSTOffsetCache dstOffsetCache;
        
        UString cachedDateString;
        double cachedDateStringValue;
        
        WeakRandom weakRandom;

        int maxReentryDepth;
#ifndef NDEBUG
        ThreadIdentifier exclusiveThread;
#endif

        void resetDateCache();

        void startSampling();
        void stopSampling();
        void dumpSampleData(ExecState* exec);
    private:
        JSGlobalData(GlobalDataType, ThreadStackType);
        static JSGlobalData*& sharedInstanceInternal();
        void createNativeThunk();
    };
    
} // namespace JSC

#endif // JSGlobalData_h