JavaScriptCore/jit/JITCall.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "JIT.h"

 #if ENABLE(JIT)

 #include "CodeBlock.h"
 #include "JITInlineMethods.h"
 #include "JSArray.h"
 #include "JSFunction.h"
 #include "Interpreter.h"
 #include "ResultType.h"
 #include "SamplingTool.h"

 #ifndef NDEBUG
 #include <stdio.h>
 #endif

 using namespace std;

 namespace JSC {

 void JIT::unlinkCall(CallLinkInfo* callLinkInfo)
 {
     // When the JSFunction is deleted the pointer embedded in the instruction stream will no longer be valid
     // (and, if a new JSFunction happened to be constructed at the same location, we could get a false positive
     // match).  Reset the check so it no longer matches.
     DataLabelPtr::patch(callLinkInfo->hotPathBegin, JSValuePtr::encode(jsImpossibleValue()));
 }

 void JIT::linkCall(JSFunction* callee, CodeBlock* calleeCodeBlock, void* ctiCode, CallLinkInfo* callLinkInfo, int callerArgCount)
 {
     // Currently we only link calls with the exact number of arguments.
     if (callerArgCount == calleeCodeBlock->m_numParameters) {
         ASSERT(!callLinkInfo->isLinked());

         calleeCodeBlock->addCaller(callLinkInfo);

         DataLabelPtr::patch(callLinkInfo->hotPathBegin, callee);
         Jump::patch(callLinkInfo->hotPathOther, ctiCode);
     }

     // patch the instruction that jumps out to the cold path, so that we only try to link once.
     void* patchCheck = reinterpret_cast<void*>(reinterpret_cast<ptrdiff_t>(callLinkInfo->hotPathBegin) + patchOffsetOpCallCompareToJump);
     Jump::patch(patchCheck, callLinkInfo->coldPathOther);
 }

 void JIT::compileOpCallInitializeCallFrame()
 {
     store32(X86::edx, Address(callFrameRegister, RegisterFile::ArgumentCount * static_cast<int>(sizeof(Register))));

     loadPtr(Address(X86::ecx, FIELD_OFFSET(JSFunction, m_scopeChain) + FIELD_OFFSET(ScopeChain, m_node)), X86::edx); // newScopeChain

     storePtr(ImmPtr(JSValuePtr::encode(noValue())), Address(callFrameRegister, RegisterFile::OptionalCalleeArguments * static_cast<int>(sizeof(Register))));
     storePtr(X86::ecx, Address(callFrameRegister, RegisterFile::Callee * static_cast<int>(sizeof(Register))));
     storePtr(X86::edx, Address(callFrameRegister, RegisterFile::ScopeChain * static_cast<int>(sizeof(Register))));
 }

 void JIT::compileOpCallSetupArgs(Instruction* instruction)
 {
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;

     // ecx holds func
     emitPutJITStubArg(X86::ecx, 1);
     emitPutJITStubArgConstant(registerOffset, 2);
     emitPutJITStubArgConstant(argCount, 3);
 }

 void JIT::compileOpCallEvalSetupArgs(Instruction* instruction)
 {
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;

     // ecx holds func
     emitPutJITStubArg(X86::ecx, 1);
     emitPutJITStubArgConstant(registerOffset, 2);
     emitPutJITStubArgConstant(argCount, 3);
 }

 void JIT::compileOpConstructSetupArgs(Instruction* instruction)
 {
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;
     int proto = instruction[5].u.operand;
     int thisRegister = instruction[6].u.operand;

     // ecx holds func
     emitPutJITStubArg(X86::ecx, 1);
     emitPutJITStubArgConstant(registerOffset, 2);
     emitPutJITStubArgConstant(argCount, 3);
     emitPutJITStubArgFromVirtualRegister(proto, 4, X86::eax);
     emitPutJITStubArgConstant(thisRegister, 5);
 }

 #if !ENABLE(JIT_OPTIMIZE_CALL)

 void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned)
 {
     int dst = instruction[1].u.operand;
     int callee = instruction[2].u.operand;
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;

     // Handle eval
     Jump wasEval;
     if (opcodeID == op_call_eval) {
         emitGetVirtualRegister(callee, X86::ecx);
         compileOpCallEvalSetupArgs(instruction);

         emitCTICall(Interpreter::cti_op_call_eval);
         wasEval = jnePtr(X86::eax, ImmPtr(jsImpossibleValue()));
     }

     emitGetVirtualRegister(callee, X86::ecx);
     // The arguments have been set up on the hot path for op_call_eval
     if (opcodeID == op_call)
         compileOpCallSetupArgs(instruction);
     else if (opcodeID == op_construct)
         compileOpConstructSetupArgs(instruction);

     // Check for JSFunctions.
     emitJumpSlowCaseIfNotJSCell(X86::ecx);
     addSlowCase(jnePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr)));

     // First, in the case of a construct, allocate the new object.
     if (opcodeID == op_construct) {
         emitCTICall(Interpreter::cti_op_construct_JSConstruct);
         emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
         emitGetVirtualRegister(callee, X86::ecx);
     }

     // Speculatively roll the callframe, assuming argCount will match the arity.
     storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
     addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);
     move(Imm32(argCount), X86::edx);

     emitNakedCall(m_interpreter->m_ctiVirtualCall);

     if (opcodeID == op_call_eval)
         wasEval.link(this);

     // Put the return value in dst. In the interpreter, op_ret does this.
     emitPutVirtualRegister(dst);

     sampleCodeBlock(m_codeBlock);
 }

 void JIT::compileOpCallSlowCase(Instruction* instruction, Vector<SlowCaseEntry>::iterator& iter, unsigned, OpcodeID opcodeID)
 {
     int dst = instruction[1].u.operand;

     linkSlowCase(iter);
     linkSlowCase(iter);

     // This handles host functions
     emitCTICall(((opcodeID == op_construct) ? Interpreter::cti_op_construct_NotJSConstruct : Interpreter::cti_op_call_NotJSFunction));
     // Put the return value in dst. In the interpreter, op_ret does this.
     emitPutVirtualRegister(dst);

     sampleCodeBlock(m_codeBlock);
 }

 #else

 static void unreachable()
 {
     ASSERT_NOT_REACHED();
     exit(1);
 }

 void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned callLinkInfoIndex)
 {
     int dst = instruction[1].u.operand;
     int callee = instruction[2].u.operand;
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;

     // Handle eval
     Jump wasEval;
     if (opcodeID == op_call_eval) {
         emitGetVirtualRegister(callee, X86::ecx);
         compileOpCallEvalSetupArgs(instruction);

         emitCTICall(Interpreter::cti_op_call_eval);
         wasEval = jnePtr(X86::eax, ImmPtr(JSValuePtr::encode(jsImpossibleValue())));
     }

     // This plants a check for a cached JSFunction value, so we can plant a fast link to the callee.
     // This deliberately leaves the callee in ecx, used when setting up the stack frame below
     emitGetVirtualRegister(callee, X86::ecx);
     DataLabelPtr addressOfLinkedFunctionCheck;
     Jump jumpToSlow = jnePtrWithPatch(X86::ecx, addressOfLinkedFunctionCheck, ImmPtr(JSValuePtr::encode(jsImpossibleValue())));
     addSlowCase(jumpToSlow);
     ASSERT(differenceBetween(addressOfLinkedFunctionCheck, jumpToSlow) == patchOffsetOpCallCompareToJump);
     m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathBegin = addressOfLinkedFunctionCheck;

     // The following is the fast case, only used whan a callee can be linked.

     // In the case of OpConstruct, call out to a cti_ function to create the new object.
     if (opcodeID == op_construct) {
         int proto = instruction[5].u.operand;
         int thisRegister = instruction[6].u.operand;

         emitPutJITStubArg(X86::ecx, 1);
         emitPutJITStubArgFromVirtualRegister(proto, 4, X86::eax);
         emitCTICall(Interpreter::cti_op_construct_JSConstruct);
         emitPutVirtualRegister(thisRegister);
         emitGetVirtualRegister(callee, X86::ecx);
     }

     // Fast version of stack frame initialization, directly relative to edi.
     // Note that this omits to set up RegisterFile::CodeBlock, which is set in the callee
     storePtr(ImmPtr(JSValuePtr::encode(noValue())), Address(callFrameRegister, (registerOffset + RegisterFile::OptionalCalleeArguments) * static_cast<int>(sizeof(Register))));
     storePtr(X86::ecx, Address(callFrameRegister, (registerOffset + RegisterFile::Callee) * static_cast<int>(sizeof(Register))));
     loadPtr(Address(X86::ecx, FIELD_OFFSET(JSFunction, m_scopeChain) + FIELD_OFFSET(ScopeChain, m_node)), X86::edx); // newScopeChain
     store32(Imm32(argCount), Address(callFrameRegister, (registerOffset + RegisterFile::ArgumentCount) * static_cast<int>(sizeof(Register))));
     storePtr(callFrameRegister, Address(callFrameRegister, (registerOffset + RegisterFile::CallerFrame) * static_cast<int>(sizeof(Register))));
     storePtr(X86::edx, Address(callFrameRegister, (registerOffset + RegisterFile::ScopeChain) * static_cast<int>(sizeof(Register))));
     addPtr(Imm32(registerOffset * sizeof(Register)), callFrameRegister);

     // Call to the callee
     m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathOther = emitNakedCall(reinterpret_cast<void*>(unreachable));

     if (opcodeID == op_call_eval)
         wasEval.link(this);

     // Put the return value in dst. In the interpreter, op_ret does this.
     emitPutVirtualRegister(dst);

     sampleCodeBlock(m_codeBlock);
 }

 void JIT::compileOpCallSlowCase(Instruction* instruction, Vector<SlowCaseEntry>::iterator& iter, unsigned callLinkInfoIndex, OpcodeID opcodeID)
 {
     int dst = instruction[1].u.operand;
     int callee = instruction[2].u.operand;
     int argCount = instruction[3].u.operand;
     int registerOffset = instruction[4].u.operand;

     linkSlowCase(iter);

     // The arguments have been set up on the hot path for op_call_eval
     if (opcodeID == op_call)
         compileOpCallSetupArgs(instruction);
     else if (opcodeID == op_construct)
         compileOpConstructSetupArgs(instruction);

     // Fast check for JS function.
     Jump callLinkFailNotObject = emitJumpIfNotJSCell(X86::ecx);
     Jump callLinkFailNotJSFunction = jnePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr));

     // First, in the case of a construct, allocate the new object.
     if (opcodeID == op_construct) {
         emitCTICall(Interpreter::cti_op_construct_JSConstruct);
         emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
         emitGetVirtualRegister(callee, X86::ecx);
     }

     move(Imm32(argCount), X86::edx);

     // Speculatively roll the callframe, assuming argCount will match the arity.
     storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
     addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);

     m_callStructureStubCompilationInfo[callLinkInfoIndex].callReturnLocation =
         emitNakedCall(m_interpreter->m_ctiVirtualCallPreLink);

     Jump storeResultForFirstRun = jump();

 // FIXME: this label can be removed, since it is a fixed offset from 'callReturnLocation'.
     // This is the address for the cold path *after* the first run (which tries to link the call).
     m_callStructureStubCompilationInfo[callLinkInfoIndex].coldPathOther = MacroAssembler::Label(this);

     // The arguments have been set up on the hot path for op_call_eval
     if (opcodeID == op_call)
         compileOpCallSetupArgs(instruction);
     else if (opcodeID == op_construct)
         compileOpConstructSetupArgs(instruction);

     // Check for JSFunctions.
     Jump isNotObject = emitJumpIfNotJSCell(X86::ecx);
     Jump isJSFunction = jePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr));

     // This handles host functions
     isNotObject.link(this);
     callLinkFailNotObject.link(this);
     callLinkFailNotJSFunction.link(this);
     emitCTICall(((opcodeID == op_construct) ? Interpreter::cti_op_construct_NotJSConstruct : Interpreter::cti_op_call_NotJSFunction));
     Jump wasNotJSFunction = jump();

     // Next, handle JSFunctions...
     isJSFunction.link(this);

     // First, in the case of a construct, allocate the new object.
     if (opcodeID == op_construct) {
         emitCTICall(Interpreter::cti_op_construct_JSConstruct);
         emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
         emitGetVirtualRegister(callee, X86::ecx);
     }

     // Speculatively roll the callframe, assuming argCount will match the arity.
     storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
     addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);
     move(Imm32(argCount), X86::edx);

     emitNakedCall(m_interpreter->m_ctiVirtualCall);

     // Put the return value in dst. In the interpreter, op_ret does this.
     wasNotJSFunction.link(this);
     storeResultForFirstRun.link(this);
     emitPutVirtualRegister(dst);

     sampleCodeBlock(m_codeBlock);
 }

 #endif

 } // namespace JSC

 #endif // ENABLE(JIT)
	/*
	* Copyright (C) 2008 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "JIT.h"

	#if ENABLE(JIT)

	#include "CodeBlock.h"
	#include "JITInlineMethods.h"
	#include "JSArray.h"
	#include "JSFunction.h"
	#include "Interpreter.h"
	#include "ResultType.h"
	#include "SamplingTool.h"

	#ifndef NDEBUG
	#include <stdio.h>
	#endif

	using namespace std;

	namespace JSC {

	void JIT::unlinkCall(CallLinkInfo* callLinkInfo)
	{
	// When the JSFunction is deleted the pointer embedded in the instruction stream will no longer be valid
	// (and, if a new JSFunction happened to be constructed at the same location, we could get a false positive
	// match). Reset the check so it no longer matches.
	DataLabelPtr::patch(callLinkInfo->hotPathBegin, JSValuePtr::encode(jsImpossibleValue()));
	}

	void JIT::linkCall(JSFunction* callee, CodeBlock* calleeCodeBlock, void* ctiCode, CallLinkInfo* callLinkInfo, int callerArgCount)
	{
	// Currently we only link calls with the exact number of arguments.
	if (callerArgCount == calleeCodeBlock->m_numParameters) {
	ASSERT(!callLinkInfo->isLinked());

	calleeCodeBlock->addCaller(callLinkInfo);

	DataLabelPtr::patch(callLinkInfo->hotPathBegin, callee);
	Jump::patch(callLinkInfo->hotPathOther, ctiCode);
	}

	// patch the instruction that jumps out to the cold path, so that we only try to link once.
	void* patchCheck = reinterpret_cast<void*>(reinterpret_cast<ptrdiff_t>(callLinkInfo->hotPathBegin) + patchOffsetOpCallCompareToJump);
	Jump::patch(patchCheck, callLinkInfo->coldPathOther);
	}

	void JIT::compileOpCallInitializeCallFrame()
	{
	store32(X86::edx, Address(callFrameRegister, RegisterFile::ArgumentCount * static_cast<int>(sizeof(Register))));

	loadPtr(Address(X86::ecx, FIELD_OFFSET(JSFunction, m_scopeChain) + FIELD_OFFSET(ScopeChain, m_node)), X86::edx); // newScopeChain

	storePtr(ImmPtr(JSValuePtr::encode(noValue())), Address(callFrameRegister, RegisterFile::OptionalCalleeArguments * static_cast<int>(sizeof(Register))));
	storePtr(X86::ecx, Address(callFrameRegister, RegisterFile::Callee * static_cast<int>(sizeof(Register))));
	storePtr(X86::edx, Address(callFrameRegister, RegisterFile::ScopeChain * static_cast<int>(sizeof(Register))));
	}

	void JIT::compileOpCallSetupArgs(Instruction* instruction)
	{
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;

	// ecx holds func
	emitPutJITStubArg(X86::ecx, 1);
	emitPutJITStubArgConstant(registerOffset, 2);
	emitPutJITStubArgConstant(argCount, 3);
	}

	void JIT::compileOpCallEvalSetupArgs(Instruction* instruction)
	{
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;

	// ecx holds func
	emitPutJITStubArg(X86::ecx, 1);
	emitPutJITStubArgConstant(registerOffset, 2);
	emitPutJITStubArgConstant(argCount, 3);
	}

	void JIT::compileOpConstructSetupArgs(Instruction* instruction)
	{
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;
	int proto = instruction[5].u.operand;
	int thisRegister = instruction[6].u.operand;

	// ecx holds func
	emitPutJITStubArg(X86::ecx, 1);
	emitPutJITStubArgConstant(registerOffset, 2);
	emitPutJITStubArgConstant(argCount, 3);
	emitPutJITStubArgFromVirtualRegister(proto, 4, X86::eax);
	emitPutJITStubArgConstant(thisRegister, 5);
	}

	#if !ENABLE(JIT_OPTIMIZE_CALL)

	void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned)
	{
	int dst = instruction[1].u.operand;
	int callee = instruction[2].u.operand;
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;

	// Handle eval
	Jump wasEval;
	if (opcodeID == op_call_eval) {
	emitGetVirtualRegister(callee, X86::ecx);
	compileOpCallEvalSetupArgs(instruction);

	emitCTICall(Interpreter::cti_op_call_eval);
	wasEval = jnePtr(X86::eax, ImmPtr(jsImpossibleValue()));
	}

	emitGetVirtualRegister(callee, X86::ecx);
	// The arguments have been set up on the hot path for op_call_eval
	if (opcodeID == op_call)
	compileOpCallSetupArgs(instruction);
	else if (opcodeID == op_construct)
	compileOpConstructSetupArgs(instruction);

	// Check for JSFunctions.
	emitJumpSlowCaseIfNotJSCell(X86::ecx);
	addSlowCase(jnePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr)));

	// First, in the case of a construct, allocate the new object.
	if (opcodeID == op_construct) {
	emitCTICall(Interpreter::cti_op_construct_JSConstruct);
	emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
	emitGetVirtualRegister(callee, X86::ecx);
	}

	// Speculatively roll the callframe, assuming argCount will match the arity.
	storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
	addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);
	move(Imm32(argCount), X86::edx);

	emitNakedCall(m_interpreter->m_ctiVirtualCall);

	if (opcodeID == op_call_eval)
	wasEval.link(this);

	// Put the return value in dst. In the interpreter, op_ret does this.
	emitPutVirtualRegister(dst);

	sampleCodeBlock(m_codeBlock);
	}

	void JIT::compileOpCallSlowCase(Instruction* instruction, Vector<SlowCaseEntry>::iterator& iter, unsigned, OpcodeID opcodeID)
	{
	int dst = instruction[1].u.operand;

	linkSlowCase(iter);
	linkSlowCase(iter);

	// This handles host functions
	emitCTICall(((opcodeID == op_construct) ? Interpreter::cti_op_construct_NotJSConstruct : Interpreter::cti_op_call_NotJSFunction));
	// Put the return value in dst. In the interpreter, op_ret does this.
	emitPutVirtualRegister(dst);

	sampleCodeBlock(m_codeBlock);
	}

	#else

	static void unreachable()
	{
	ASSERT_NOT_REACHED();
	exit(1);
	}

	void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned callLinkInfoIndex)
	{
	int dst = instruction[1].u.operand;
	int callee = instruction[2].u.operand;
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;

	// Handle eval
	Jump wasEval;
	if (opcodeID == op_call_eval) {
	emitGetVirtualRegister(callee, X86::ecx);
	compileOpCallEvalSetupArgs(instruction);

	emitCTICall(Interpreter::cti_op_call_eval);
	wasEval = jnePtr(X86::eax, ImmPtr(JSValuePtr::encode(jsImpossibleValue())));
	}

	// This plants a check for a cached JSFunction value, so we can plant a fast link to the callee.
	// This deliberately leaves the callee in ecx, used when setting up the stack frame below
	emitGetVirtualRegister(callee, X86::ecx);
	DataLabelPtr addressOfLinkedFunctionCheck;
	Jump jumpToSlow = jnePtrWithPatch(X86::ecx, addressOfLinkedFunctionCheck, ImmPtr(JSValuePtr::encode(jsImpossibleValue())));
	addSlowCase(jumpToSlow);
	ASSERT(differenceBetween(addressOfLinkedFunctionCheck, jumpToSlow) == patchOffsetOpCallCompareToJump);
	m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathBegin = addressOfLinkedFunctionCheck;

	// The following is the fast case, only used whan a callee can be linked.

	// In the case of OpConstruct, call out to a cti_ function to create the new object.
	if (opcodeID == op_construct) {
	int proto = instruction[5].u.operand;
	int thisRegister = instruction[6].u.operand;

	emitPutJITStubArg(X86::ecx, 1);
	emitPutJITStubArgFromVirtualRegister(proto, 4, X86::eax);
	emitCTICall(Interpreter::cti_op_construct_JSConstruct);
	emitPutVirtualRegister(thisRegister);
	emitGetVirtualRegister(callee, X86::ecx);
	}

	// Fast version of stack frame initialization, directly relative to edi.
	// Note that this omits to set up RegisterFile::CodeBlock, which is set in the callee
	storePtr(ImmPtr(JSValuePtr::encode(noValue())), Address(callFrameRegister, (registerOffset + RegisterFile::OptionalCalleeArguments) * static_cast<int>(sizeof(Register))));
	storePtr(X86::ecx, Address(callFrameRegister, (registerOffset + RegisterFile::Callee) * static_cast<int>(sizeof(Register))));
	loadPtr(Address(X86::ecx, FIELD_OFFSET(JSFunction, m_scopeChain) + FIELD_OFFSET(ScopeChain, m_node)), X86::edx); // newScopeChain
	store32(Imm32(argCount), Address(callFrameRegister, (registerOffset + RegisterFile::ArgumentCount) * static_cast<int>(sizeof(Register))));
	storePtr(callFrameRegister, Address(callFrameRegister, (registerOffset + RegisterFile::CallerFrame) * static_cast<int>(sizeof(Register))));
	storePtr(X86::edx, Address(callFrameRegister, (registerOffset + RegisterFile::ScopeChain) * static_cast<int>(sizeof(Register))));
	addPtr(Imm32(registerOffset * sizeof(Register)), callFrameRegister);

	// Call to the callee
	m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathOther = emitNakedCall(reinterpret_cast<void*>(unreachable));

	if (opcodeID == op_call_eval)
	wasEval.link(this);

	// Put the return value in dst. In the interpreter, op_ret does this.
	emitPutVirtualRegister(dst);

	sampleCodeBlock(m_codeBlock);
	}

	void JIT::compileOpCallSlowCase(Instruction* instruction, Vector<SlowCaseEntry>::iterator& iter, unsigned callLinkInfoIndex, OpcodeID opcodeID)
	{
	int dst = instruction[1].u.operand;
	int callee = instruction[2].u.operand;
	int argCount = instruction[3].u.operand;
	int registerOffset = instruction[4].u.operand;

	linkSlowCase(iter);

	// The arguments have been set up on the hot path for op_call_eval
	if (opcodeID == op_call)
	compileOpCallSetupArgs(instruction);
	else if (opcodeID == op_construct)
	compileOpConstructSetupArgs(instruction);

	// Fast check for JS function.
	Jump callLinkFailNotObject = emitJumpIfNotJSCell(X86::ecx);
	Jump callLinkFailNotJSFunction = jnePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr));

	// First, in the case of a construct, allocate the new object.
	if (opcodeID == op_construct) {
	emitCTICall(Interpreter::cti_op_construct_JSConstruct);
	emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
	emitGetVirtualRegister(callee, X86::ecx);
	}

	move(Imm32(argCount), X86::edx);

	// Speculatively roll the callframe, assuming argCount will match the arity.
	storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
	addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);

	m_callStructureStubCompilationInfo[callLinkInfoIndex].callReturnLocation =
	emitNakedCall(m_interpreter->m_ctiVirtualCallPreLink);

	Jump storeResultForFirstRun = jump();

	// FIXME: this label can be removed, since it is a fixed offset from 'callReturnLocation'.
	// This is the address for the cold path after the first run (which tries to link the call).
	m_callStructureStubCompilationInfo[callLinkInfoIndex].coldPathOther = MacroAssembler::Label(this);

	// The arguments have been set up on the hot path for op_call_eval
	if (opcodeID == op_call)
	compileOpCallSetupArgs(instruction);
	else if (opcodeID == op_construct)
	compileOpConstructSetupArgs(instruction);

	// Check for JSFunctions.
	Jump isNotObject = emitJumpIfNotJSCell(X86::ecx);
	Jump isJSFunction = jePtr(Address(X86::ecx), ImmPtr(m_interpreter->m_jsFunctionVptr));

	// This handles host functions
	isNotObject.link(this);
	callLinkFailNotObject.link(this);
	callLinkFailNotJSFunction.link(this);
	emitCTICall(((opcodeID == op_construct) ? Interpreter::cti_op_construct_NotJSConstruct : Interpreter::cti_op_call_NotJSFunction));
	Jump wasNotJSFunction = jump();

	// Next, handle JSFunctions...
	isJSFunction.link(this);

	// First, in the case of a construct, allocate the new object.
	if (opcodeID == op_construct) {
	emitCTICall(Interpreter::cti_op_construct_JSConstruct);
	emitPutVirtualRegister(registerOffset - RegisterFile::CallFrameHeaderSize - argCount);
	emitGetVirtualRegister(callee, X86::ecx);
	}

	// Speculatively roll the callframe, assuming argCount will match the arity.
	storePtr(callFrameRegister, Address(callFrameRegister, (RegisterFile::CallerFrame + registerOffset) * static_cast<int>(sizeof(Register))));
	addPtr(Imm32(registerOffset * static_cast<int>(sizeof(Register))), callFrameRegister);
	move(Imm32(argCount), X86::edx);

	emitNakedCall(m_interpreter->m_ctiVirtualCall);

	// Put the return value in dst. In the interpreter, op_ret does this.
	wasNotJSFunction.link(this);
	storeResultForFirstRun.link(this);
	emitPutVirtualRegister(dst);

	sampleCodeBlock(m_codeBlock);
	}

	#endif

	} // namespace JSC

	#endif // ENABLE(JIT)