dfg/DFGOSRExit.h

   1 /*
   2  * Copyright (C) 2011 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 DFGOSRExit_h
  27 #define DFGOSRExit_h
  28
  29 #include <wtf/Platform.h>
  30
  31 #if ENABLE(DFG_JIT)
  32
  33 #include "CodeOrigin.h"
  34 #include "DFGCommon.h"
  35 #include "DFGCorrectableJumpPoint.h"
  36 #include "DFGExitProfile.h"
  37 #include "DFGGPRInfo.h"
  38 #include "MacroAssembler.h"
  39 #include "MethodOfGettingAValueProfile.h"
  40 #include "Operands.h"
  41 #include "ValueProfile.h"
  42 #include "ValueRecovery.h"
  43 #include <wtf/Vector.h>
  44
  45 namespace JSC { namespace DFG {
  46
  47 class SpeculativeJIT;
  48
  49 // This enum describes the types of additional recovery that
  50 // may need be performed should a speculation check fail.
  51 enum SpeculationRecoveryType {
  52     SpeculativeAdd,
  53     BooleanSpeculationCheck
  54 };
  55
  56 // === SpeculationRecovery ===
  57 //
  58 // This class provides additional information that may be associated with a
  59 // speculation check - for example
  60 class SpeculationRecovery {
  61 public:
  62     SpeculationRecovery(SpeculationRecoveryType type, GPRReg dest, GPRReg src)
  63         : m_type(type)
  64         , m_dest(dest)
  65         , m_src(src)
  66     {
  67     }
  68
  69     SpeculationRecoveryType type() { return m_type; }
  70     GPRReg dest() { return m_dest; }
  71     GPRReg src() { return m_src; }
  72
  73 private:
  74     // Indicates the type of additional recovery to be performed.
  75     SpeculationRecoveryType m_type;
  76     // different recovery types may required different additional information here.
  77     GPRReg m_dest;
  78     GPRReg m_src;
  79 };
  80
  81 // === OSRExit ===
  82 //
  83 // This structure describes how to exit the speculative path by
  84 // going into baseline code.
  85 struct OSRExit {
  86     OSRExit(ExitKind, JSValueSource, MethodOfGettingAValueProfile, MacroAssembler::Jump, SpeculativeJIT*, unsigned recoveryIndex = 0);
  87
  88     MacroAssemblerCodeRef m_code;
  89
  90     JSValueSource m_jsValueSource;
  91     MethodOfGettingAValueProfile m_valueProfile;
  92
  93     CorrectableJumpPoint m_check;
  94     NodeIndex m_nodeIndex;
  95     CodeOrigin m_codeOrigin;
  96     CodeOrigin m_codeOriginForExitProfile;
  97
  98     unsigned m_recoveryIndex;
  99
 100     ExitKind m_kind;
 101     uint32_t m_count;
 102
 103     // Convenient way of iterating over ValueRecoveries while being
 104     // generic over argument versus variable.
 105     int numberOfRecoveries() const { return m_arguments.size() + m_variables.size(); }
 106     const ValueRecovery& valueRecovery(int index) const
 107     {
 108         if (index < (int)m_arguments.size())
 109             return m_arguments[index];
 110         return m_variables[index - m_arguments.size()];
 111     }
 112     ValueRecovery& valueRecoveryForOperand(int operand)
 113     {
 114         if (operandIsArgument(operand))
 115             return m_arguments[operandToArgument(operand)];
 116         return m_variables[operand];
 117     }
 118     bool isArgument(int index) const { return index < (int)m_arguments.size(); }
 119     bool isVariable(int index) const { return !isArgument(index); }
 120     int argumentForIndex(int index) const
 121     {
 122         return index;
 123     }
 124     int variableForIndex(int index) const
 125     {
 126         return index - m_arguments.size();
 127     }
 128     int operandForIndex(int index) const
 129     {
 130         if (index < (int)m_arguments.size())
 131             return operandToArgument(index);
 132         return index - m_arguments.size();
 133     }
 134
 135     bool considerAddingAsFrequentExitSite(CodeBlock* dfgCodeBlock, CodeBlock* profiledCodeBlock)
 136     {
 137         if (!m_count || !exitKindIsCountable(m_kind))
 138             return false;
 139         return considerAddingAsFrequentExitSiteSlow(dfgCodeBlock, profiledCodeBlock);
 140     }
 141
 142     void dump(FILE* out) const;
 143
 144     Vector<ValueRecovery, 0> m_arguments;
 145     Vector<ValueRecovery, 0> m_variables;
 146     int m_lastSetOperand;
 147
 148 private:
 149     bool considerAddingAsFrequentExitSiteSlow(CodeBlock* dfgCodeBlock, CodeBlock* profiledCodeBlock);
 150 };
 151
 152 #if DFG_ENABLE(VERBOSE_SPECULATION_FAILURE)
 153 struct SpeculationFailureDebugInfo {
 154     CodeBlock* codeBlock;
 155     NodeIndex nodeIndex;
 156 };
 157 #endif
 158
 159 } } // namespace JSC::DFG
 160
 161 #endif // ENABLE(DFG_JIT)
 162
 163 #endif // DFGOSRExit_h
 164