jit/SpecializedThunkJIT.h

   1 /*
   2  * Copyright (C) 2010 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. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef SpecializedThunkJIT_h
  27 #define SpecializedThunkJIT_h
  28
  29 #if ENABLE(JIT)
  30
  31 #include "Executable.h"
  32 #include "JSInterfaceJIT.h"
  33 #include "LinkBuffer.h"
  34
  35 namespace JSC {
  36
  37     class SpecializedThunkJIT : public JSInterfaceJIT {
  38     public:
  39         static const int ThisArgument = -1;
  40         SpecializedThunkJIT(int expectedArgCount)
  41         {
  42             // Check that we have the expected number of arguments
  43             m_failures.append(branch32(NotEqual, payloadFor(JSStack::ArgumentCount), TrustedImm32(expectedArgCount + 1)));
  44         }
  45
  46         void loadDoubleArgument(int argument, FPRegisterID dst, RegisterID scratch)
  47         {
  48             unsigned src = CallFrame::argumentOffset(argument);
  49             m_failures.append(emitLoadDouble(src, dst, scratch));
  50         }
  51
  52         void loadCellArgument(int argument, RegisterID dst)
  53         {
  54             unsigned src = CallFrame::argumentOffset(argument);
  55             m_failures.append(emitLoadJSCell(src, dst));
  56         }
  57
  58         void loadJSStringArgument(VM& vm, int argument, RegisterID dst)
  59         {
  60             loadCellArgument(argument, dst);
  61             m_failures.append(branchPtr(NotEqual, Address(dst, JSCell::structureOffset()), TrustedImmPtr(vm.stringStructure.get())));
  62         }
  63
  64         void loadInt32Argument(int argument, RegisterID dst, Jump& failTarget)
  65         {
  66             unsigned src = CallFrame::argumentOffset(argument);
  67             failTarget = emitLoadInt32(src, dst);
  68         }
  69
  70         void loadInt32Argument(int argument, RegisterID dst)
  71         {
  72             Jump conversionFailed;
  73             loadInt32Argument(argument, dst, conversionFailed);
  74             m_failures.append(conversionFailed);
  75         }
  76
  77         void appendFailure(const Jump& failure)
  78         {
  79             m_failures.append(failure);
  80         }
  81
  82         void returnJSValue(RegisterID src)
  83         {
  84             if (src != regT0)
  85                 move(src, regT0);
  86             loadPtr(payloadFor(JSStack::CallerFrame, callFrameRegister), callFrameRegister);
  87             ret();
  88         }
  89
  90         void returnDouble(FPRegisterID src)
  91         {
  92 #if USE(JSVALUE64)
  93             moveDoubleTo64(src, regT0);
  94             Jump zero = branchTest64(Zero, regT0);
  95             sub64(tagTypeNumberRegister, regT0);
  96             Jump done = jump();
  97             zero.link(this);
  98             move(tagTypeNumberRegister, regT0);
  99             done.link(this);
 100 #else
 101             storeDouble(src, Address(stackPointerRegister, -(int)sizeof(double)));
 102             loadPtr(Address(stackPointerRegister, OBJECT_OFFSETOF(JSValue, u.asBits.tag) - sizeof(double)), regT1);
 103             loadPtr(Address(stackPointerRegister, OBJECT_OFFSETOF(JSValue, u.asBits.payload) - sizeof(double)), regT0);
 104             Jump lowNonZero = branchTestPtr(NonZero, regT1);
 105             Jump highNonZero = branchTestPtr(NonZero, regT0);
 106             move(TrustedImm32(0), regT0);
 107             move(TrustedImm32(Int32Tag), regT1);
 108             lowNonZero.link(this);
 109             highNonZero.link(this);
 110 #endif
 111             loadPtr(payloadFor(JSStack::CallerFrame, callFrameRegister), callFrameRegister);
 112             ret();
 113         }
 114
 115         void returnInt32(RegisterID src)
 116         {
 117             if (src != regT0)
 118                 move(src, regT0);
 119             tagReturnAsInt32();
 120             loadPtr(payloadFor(JSStack::CallerFrame, callFrameRegister), callFrameRegister);
 121             ret();
 122         }
 123
 124         void returnJSCell(RegisterID src)
 125         {
 126             if (src != regT0)
 127                 move(src, regT0);
 128             tagReturnAsJSCell();
 129             loadPtr(payloadFor(JSStack::CallerFrame, callFrameRegister), callFrameRegister);
 130             ret();
 131         }
 132
 133         MacroAssemblerCodeRef finalize(VM& vm, MacroAssemblerCodePtr fallback, const char* thunkKind)
 134         {
 135             LinkBuffer patchBuffer(vm, this, GLOBAL_THUNK_ID);
 136             patchBuffer.link(m_failures, CodeLocationLabel(fallback));
 137             for (unsigned i = 0; i < m_calls.size(); i++)
 138                 patchBuffer.link(m_calls[i].first, m_calls[i].second);
 139             return FINALIZE_CODE(patchBuffer, ("Specialized thunk for %s", thunkKind));
 140         }
 141
 142         // Assumes that the target function uses fpRegister0 as the first argument
 143         // and return value. Like any sensible architecture would.
 144         void callDoubleToDouble(FunctionPtr function)
 145         {
 146             m_calls.append(std::make_pair(call(), function));
 147         }
 148
 149         void callDoubleToDoublePreservingReturn(FunctionPtr function)
 150         {
 151             if (!isX86())
 152                 preserveReturnAddressAfterCall(regT3);
 153             callDoubleToDouble(function);
 154             if (!isX86())
 155                 restoreReturnAddressBeforeReturn(regT3);
 156         }
 157
 158     private:
 159
 160         void tagReturnAsInt32()
 161         {
 162 #if USE(JSVALUE64)
 163             or64(tagTypeNumberRegister, regT0);
 164 #else
 165             move(TrustedImm32(JSValue::Int32Tag), regT1);
 166 #endif
 167         }
 168
 169         void tagReturnAsJSCell()
 170         {
 171 #if USE(JSVALUE32_64)
 172             move(TrustedImm32(JSValue::CellTag), regT1);
 173 #endif
 174         }
 175
 176         MacroAssembler::JumpList m_failures;
 177         Vector<std::pair<Call, FunctionPtr> > m_calls;
 178     };
 179
 180 }
 181
 182 #endif // ENABLE(JIT)
 183
 184 #endif // SpecializedThunkJIT_h