interpreter/Register.h

   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 Register_h
  30 #define Register_h
  31
  32 #include "JSValue.h"
  33 #include <wtf/Assertions.h>
  34 #include <wtf/VectorTraits.h>
  35
  36 namespace JSC {
  37
  38     class CodeBlock;
  39     class ExecState;
  40     class JSActivation;
  41     class JSObject;
  42     class JSPropertyNameIterator;
  43     class ScopeChainNode;
  44
  45     struct Instruction;
  46
  47     typedef ExecState CallFrame;
  48
  49     class Register {
  50         WTF_MAKE_FAST_ALLOCATED;
  51     public:
  52         Register();
  53
  54         Register(const JSValue&);
  55         Register& operator=(const JSValue&);
  56         JSValue jsValue() const;
  57         EncodedJSValue encodedJSValue() const;
  58
  59         Register& operator=(CallFrame*);
  60         Register& operator=(CodeBlock*);
  61         Register& operator=(ScopeChainNode*);
  62         Register& operator=(Instruction*);
  63
  64         int32_t i() const;
  65         JSActivation* activation() const;
  66         CallFrame* callFrame() const;
  67         CodeBlock* codeBlock() const;
  68         JSObject* function() const;
  69         JSPropertyNameIterator* propertyNameIterator() const;
  70         ScopeChainNode* scopeChain() const;
  71         Instruction* vPC() const;
  72
  73         static Register withInt(int32_t i)
  74         {
  75             Register r = jsNumber(i);
  76             return r;
  77         }
  78
  79         static inline Register withCallee(JSObject* callee);
  80
  81     private:
  82         union {
  83             EncodedJSValue value;
  84             CallFrame* callFrame;
  85             CodeBlock* codeBlock;
  86             Instruction* vPC;
  87         } u;
  88     };
  89
  90     ALWAYS_INLINE Register::Register()
  91     {
  92 #ifndef NDEBUG
  93         *this = JSValue();
  94 #endif
  95     }
  96
  97     ALWAYS_INLINE Register::Register(const JSValue& v)
  98     {
  99 #if ENABLE(JSC_ZOMBIES)
 100         ASSERT(!v.isZombie());
 101 #endif
 102         u.value = JSValue::encode(v);
 103     }
 104
 105     ALWAYS_INLINE Register& Register::operator=(const JSValue& v)
 106     {
 107 #if ENABLE(JSC_ZOMBIES)
 108         ASSERT(!v.isZombie());
 109 #endif
 110         u.value = JSValue::encode(v);
 111         return *this;
 112     }
 113
 114     ALWAYS_INLINE JSValue Register::jsValue() const
 115     {
 116         return JSValue::decode(u.value);
 117     }
 118
 119     ALWAYS_INLINE EncodedJSValue Register::encodedJSValue() const
 120     {
 121         return u.value;
 122     }
 123
 124     // Interpreter functions
 125
 126     ALWAYS_INLINE Register& Register::operator=(CallFrame* callFrame)
 127     {
 128         u.callFrame = callFrame;
 129         return *this;
 130     }
 131
 132     ALWAYS_INLINE Register& Register::operator=(CodeBlock* codeBlock)
 133     {
 134         u.codeBlock = codeBlock;
 135         return *this;
 136     }
 137
 138     ALWAYS_INLINE Register& Register::operator=(Instruction* vPC)
 139     {
 140         u.vPC = vPC;
 141         return *this;
 142     }
 143
 144     ALWAYS_INLINE int32_t Register::i() const
 145     {
 146         return jsValue().asInt32();
 147     }
 148
 149     ALWAYS_INLINE CallFrame* Register::callFrame() const
 150     {
 151         return u.callFrame;
 152     }
 153
 154     ALWAYS_INLINE CodeBlock* Register::codeBlock() const
 155     {
 156         return u.codeBlock;
 157     }
 158
 159     ALWAYS_INLINE Instruction* Register::vPC() const
 160     {
 161         return u.vPC;
 162     }
 163
 164 } // namespace JSC
 165
 166 namespace WTF {
 167
 168     template<> struct VectorTraits<JSC::Register> : VectorTraitsBase<true, JSC::Register> { };
 169
 170 } // namespace WTF
 171
 172 #endif // Register_h