dfg/DFGOSRExit.h

   1 /*
   2  * Copyright (C) 2011, 2013 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 #if ENABLE(DFG_JIT)
  30
  31 #include "CodeOrigin.h"
  32 #include "DFGCommon.h"
  33 #include "DFGExitProfile.h"
  34 #include "DFGOSRExitBase.h"
  35 #include "DFGValueRecoveryOverride.h"
  36 #include "GPRInfo.h"
  37 #include "MacroAssembler.h"
  38 #include "MethodOfGettingAValueProfile.h"
  39 #include "Operands.h"
  40 #include "ValueProfile.h"
  41 #include "ValueRecovery.h"
  42 #include <wtf/Vector.h>
  43
  44 namespace JSC { namespace DFG {
  45
  46 class SpeculativeJIT;
  47 struct BasicBlock;
  48 struct Node;
  49
  50 // This enum describes the types of additional recovery that
  51 // may need be performed should a speculation check fail.
  52 enum SpeculationRecoveryType {
  53     SpeculativeAdd,
  54     BooleanSpeculationCheck
  55 };
  56
  57 // === SpeculationRecovery ===
  58 //
  59 // This class provides additional information that may be associated with a
  60 // speculation check - for example
  61 class SpeculationRecovery {
  62 public:
  63     SpeculationRecovery(SpeculationRecoveryType type, GPRReg dest, GPRReg src)
  64         : m_type(type)
  65         , m_dest(dest)
  66         , m_src(src)
  67     {
  68     }
  69
  70     SpeculationRecoveryType type() { return m_type; }
  71     GPRReg dest() { return m_dest; }
  72     GPRReg src() { return m_src; }
  73
  74 private:
  75     // Indicates the type of additional recovery to be performed.
  76     SpeculationRecoveryType m_type;
  77     // different recovery types may required different additional information here.
  78     GPRReg m_dest;
  79     GPRReg m_src;
  80 };
  81
  82 // === OSRExit ===
  83 //
  84 // This structure describes how to exit the speculative path by
  85 // going into baseline code.
  86 struct OSRExit : public OSRExitBase {
  87     OSRExit(ExitKind, JSValueSource, MethodOfGettingAValueProfile, SpeculativeJIT*, unsigned streamIndex, unsigned recoveryIndex = UINT_MAX);
  88
  89     MacroAssemblerCodeRef m_code;
  90
  91     JSValueSource m_jsValueSource;
  92     MethodOfGettingAValueProfile m_valueProfile;
  93
  94     unsigned m_patchableCodeOffset;
  95
  96     unsigned m_recoveryIndex;
  97
  98     void setPatchableCodeOffset(MacroAssembler::PatchableJump);
  99     MacroAssembler::Jump getPatchableCodeOffsetAsJump() const;
 100     CodeLocationJump codeLocationForRepatch(CodeBlock*) const;
 101     void correctJump(LinkBuffer&);
 102
 103     unsigned m_streamIndex;
 104
 105     RefPtr<ValueRecoveryOverride> m_valueRecoveryOverride;
 106
 107     bool considerAddingAsFrequentExitSite(CodeBlock* profiledCodeBlock)
 108     {
 109         return OSRExitBase::considerAddingAsFrequentExitSite(profiledCodeBlock, ExitFromDFG);
 110     }
 111 };
 112
 113 struct SpeculationFailureDebugInfo {
 114     CodeBlock* codeBlock;
 115     ExitKind kind;
 116     unsigned bytecodeOffset;
 117 };
 118
 119 } } // namespace JSC::DFG
 120
 121 #endif // ENABLE(DFG_JIT)
 122
 123 #endif // DFGOSRExit_h
 124