bytecode/ResolveOperation.h

   1 /*
   2  * Copyright (C) 2012 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 #ifndef ResolveOperation_h
  27 #define ResolveOperation_h
  28
  29 #include "PropertyOffset.h"
  30 #include "WriteBarrier.h"
  31
  32 #include <wtf/Vector.h>
  33
  34 namespace JSC {
  35
  36 class Structure;
  37
  38 struct ResolveOperation {
  39     typedef enum {
  40         Fail,
  41         SetBaseToUndefined,
  42         ReturnScopeAsBase,
  43         SetBaseToScope,
  44         SetBaseToGlobal,
  45         GetAndReturnScopedVar,
  46         GetAndReturnGlobalVar,
  47         GetAndReturnGlobalVarWatchable,
  48         SkipTopScopeNode,
  49         SkipScopes,
  50         ReturnGlobalObjectAsBase,
  51         GetAndReturnGlobalProperty,
  52         CheckForDynamicEntriesBeforeGlobalScope
  53     } ResolveOperationType;
  54
  55     ResolveOperationType m_operation;
  56     WriteBarrier<Structure> m_structure;
  57     union {
  58         PropertyOffset m_offset;
  59         WriteBarrier<Unknown>* m_registerAddress;
  60         int m_scopesToSkip;
  61         int m_activationRegister;
  62     };
  63     static ResolveOperation getAndReturnScopedVar(PropertyOffset offset)
  64     {
  65         ResolveOperation op;
  66         op.m_operation = GetAndReturnScopedVar;
  67         op.m_offset = offset;
  68         return op;
  69     }
  70     static ResolveOperation checkForDynamicEntriesBeforeGlobalScope()
  71     {
  72         ResolveOperation op;
  73         op.m_operation = CheckForDynamicEntriesBeforeGlobalScope;
  74         return op;
  75     }
  76
  77     static ResolveOperation getAndReturnGlobalVar(WriteBarrier<Unknown>* registerAddress, bool couldBeWatched)
  78     {
  79         ResolveOperation op;
  80         op.m_operation = couldBeWatched ? GetAndReturnGlobalVarWatchable : GetAndReturnGlobalVar;
  81         op.m_registerAddress = registerAddress;
  82         return op;
  83     }
  84     static ResolveOperation getAndReturnGlobalProperty()
  85     {
  86         ResolveOperation op;
  87         op.m_operation = GetAndReturnGlobalProperty;
  88         return op;
  89     }
  90     static ResolveOperation resolveFail()
  91     {
  92         ResolveOperation op;
  93         op.m_operation = Fail;
  94         return op;
  95     }
  96     static ResolveOperation skipTopScopeNode(int activationRegister)
  97     {
  98         ResolveOperation op;
  99         op.m_operation = SkipTopScopeNode;
 100         op.m_activationRegister = activationRegister;
 101         return op;
 102     }
 103     static ResolveOperation skipScopes(int scopesToSkip)
 104     {
 105         ResolveOperation op;
 106         op.m_operation = SkipScopes;
 107         op.m_scopesToSkip = scopesToSkip;
 108         return op;
 109     }
 110     static ResolveOperation returnGlobalObjectAsBase()
 111     {
 112         ResolveOperation op;
 113         op.m_operation = ReturnGlobalObjectAsBase;
 114         return op;
 115     }
 116     static ResolveOperation setBaseToGlobal()
 117     {
 118         ResolveOperation op;
 119         op.m_operation = SetBaseToGlobal;
 120         return op;
 121     }
 122     static ResolveOperation setBaseToUndefined()
 123     {
 124         ResolveOperation op;
 125         op.m_operation = SetBaseToUndefined;
 126         return op;
 127     }
 128     static ResolveOperation setBaseToScope()
 129     {
 130         ResolveOperation op;
 131         op.m_operation = SetBaseToScope;
 132         return op;
 133     }
 134     static ResolveOperation returnScopeAsBase()
 135     {
 136         ResolveOperation op;
 137         op.m_operation = ReturnScopeAsBase;
 138         return op;
 139     }
 140 };
 141
 142 typedef Vector<ResolveOperation> ResolveOperations;
 143
 144 struct PutToBaseOperation {
 145     PutToBaseOperation(bool isStrict)
 146         : m_kind(Uninitialised)
 147         , m_isDynamic(false)
 148         , m_isStrict(isStrict)
 149         , m_predicatePointer(0)
 150     {
 151
 152     }
 153     enum Kind { Uninitialised, Generic, Readonly, GlobalVariablePut, GlobalVariablePutChecked, GlobalPropertyPut, VariablePut };
 154     union {
 155         Kind m_kind : 8;
 156         uint8_t m_kindAsUint8;
 157     };
 158     bool m_isDynamic : 8;
 159     bool m_isStrict : 8;
 160     union {
 161         bool* m_predicatePointer;
 162         unsigned m_scopeDepth;
 163     };
 164     WriteBarrier<Structure> m_structure;
 165     union {
 166         // Used for GlobalVariablePut
 167         WriteBarrier<Unknown>* m_registerAddress;
 168
 169         // Used for GlobalPropertyPut and VariablePut
 170         struct {
 171             PropertyOffset m_offset;
 172             int32_t m_offsetInButterfly;
 173         };
 174     };
 175 };
 176 }
 177
 178 #endif // ResolveOperation_h