Updated WebKit from /home/shausman/src/webkit/trunk to qtwebkit-4.6-snapshot-15062009 ( 65232bf00dc494ebfd978f998c88f58d18ecce1e )

1 files changed, 1046 insertions, 438 deletions

diff --git a/src/3rdparty/webkit/JavaScriptCore/jit/JITArithmetic.cpp b/src/3rdparty/webkit/JavaScriptCore/jit/JITArithmetic.cpp
index f95bab8..2ceb935 100644
--- a/src/3rdparty/webkit/JavaScriptCore/jit/JITArithmetic.cpp
+++ b/src/3rdparty/webkit/JavaScriptCore/jit/JITArithmetic.cpp
@@ -30,6 +30,7 @@
 
 #include "CodeBlock.h"
 #include "JITInlineMethods.h"
+#include "JITStubCall.h"
 #include "JSArray.h"
 #include "JSFunction.h"
 #include "Interpreter.h"
@@ -40,35 +41,43 @@
 #include <stdio.h>
 #endif
 
-#define __ m_assembler.
 
 using namespace std;
 
 namespace JSC {
 
-void JIT::compileFastArith_op_lshift(unsigned result, unsigned op1, unsigned op2)
+void JIT::emit_op_lshift(Instruction* currentInstruction)
 {
-    emitGetVirtualRegisters(op1, X86::eax, op2, X86::ecx);
-    // FIXME: would we be better using 'emitJumpSlowCaseIfNotImmNums'? - we *probably* ought to be consistent.
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
-    emitJumpSlowCaseIfNotImmNum(X86::ecx);
-    emitFastArithImmToInt(X86::eax);
-    emitFastArithImmToInt(X86::ecx);
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    emitGetVirtualRegisters(op1, regT0, op2, regT2);
+    // FIXME: would we be better using 'emitJumpSlowCaseIfNotImmediateIntegers'? - we *probably* ought to be consistent.
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
+    emitJumpSlowCaseIfNotImmediateInteger(regT2);
+    emitFastArithImmToInt(regT0);
+    emitFastArithImmToInt(regT2);
 #if !PLATFORM(X86)
     // Mask with 0x1f as per ecma-262 11.7.2 step 7.
     // On 32-bit x86 this is not necessary, since the shift anount is implicitly masked in the instruction.
-    and32(Imm32(0x1f), X86::ecx);
+    and32(Imm32(0x1f), regT2);
 #endif
-    lshift32(X86::ecx, X86::eax);
+    lshift32(regT2, regT0);
 #if !USE(ALTERNATE_JSIMMEDIATE)
-    addSlowCase(joAdd32(X86::eax, X86::eax));
-    signExtend32ToPtr(X86::eax, X86::eax);
+    addSlowCase(branchAdd32(Overflow, regT0, regT0));
+    signExtend32ToPtr(regT0, regT0);
 #endif
-    emitFastArithReTagImmediate(X86::eax, X86::eax);
+    emitFastArithReTagImmediate(regT0, regT0);
     emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_lshift(unsigned result, unsigned op1, unsigned op2, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_lshift(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
 #if USE(ALTERNATE_JSIMMEDIATE)
     UNUSED_PARAM(op1);
     UNUSED_PARAM(op2);
@@ -79,652 +88,1137 @@ void JIT::compileFastArithSlow_op_lshift(unsigned result, unsigned op1, unsigned
     Jump notImm1 = getSlowCase(iter);
     Jump notImm2 = getSlowCase(iter);
     linkSlowCase(iter);
-    emitGetVirtualRegisters(op1, X86::eax, op2, X86::ecx);
+    emitGetVirtualRegisters(op1, regT0, op2, regT2);
     notImm1.link(this);
     notImm2.link(this);
 #endif
-    emitPutJITStubArg(X86::eax, 1);
-    emitPutJITStubArg(X86::ecx, 2);
-    emitCTICall(Interpreter::cti_op_lshift);
-    emitPutVirtualRegister(result);
+    JITStubCall stubCall(this, JITStubs::cti_op_lshift);
+    stubCall.addArgument(regT0);
+    stubCall.addArgument(regT2);
+    stubCall.call(result);
 }
 
-void JIT::compileFastArith_op_rshift(unsigned result, unsigned op1, unsigned op2)
+void JIT::emit_op_rshift(Instruction* currentInstruction)
 {
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
     if (isOperandConstantImmediateInt(op2)) {
-        emitGetVirtualRegister(op1, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+        // isOperandConstantImmediateInt(op2) => 1 SlowCase
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
         // Mask with 0x1f as per ecma-262 11.7.2 step 7.
 #if USE(ALTERNATE_JSIMMEDIATE)
-        rshift32(Imm32(JSImmediate::getTruncatedUInt32(getConstantOperand(op2)) & 0x1f), X86::eax);
+        rshift32(Imm32(getConstantOperandImmediateInt(op2) & 0x1f), regT0);
 #else
-        rshiftPtr(Imm32(JSImmediate::getTruncatedUInt32(getConstantOperand(op2)) & 0x1f), X86::eax);
+        rshiftPtr(Imm32(getConstantOperandImmediateInt(op2) & 0x1f), regT0);
 #endif
     } else {
-        emitGetVirtualRegisters(op1, X86::eax, op2, X86::ecx);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::ecx);
-        emitFastArithImmToInt(X86::ecx);
+        emitGetVirtualRegisters(op1, regT0, op2, regT2);
+        if (supportsFloatingPoint()) {
+            Jump lhsIsInt = emitJumpIfImmediateInteger(regT0);
+#if USE(ALTERNATE_JSIMMEDIATE)
+            // supportsFloatingPoint() && USE(ALTERNATE_JSIMMEDIATE) => 3 SlowCases
+            addSlowCase(emitJumpIfNotImmediateNumber(regT0));
+            movePtrToDouble(regT0, fpRegT0);
+            addSlowCase(branchTruncateDoubleToInt32(fpRegT0, regT0));
+#else
+            // supportsFloatingPoint() && !USE(ALTERNATE_JSIMMEDIATE) => 5 SlowCases (of which 1 IfNotJSCell)
+            emitJumpSlowCaseIfNotJSCell(regT0, op1);
+            addSlowCase(checkStructure(regT0, m_globalData->numberStructure.get()));
+            loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
+            addSlowCase(branchTruncateDoubleToInt32(fpRegT0, regT0));
+            addSlowCase(branchAdd32(Overflow, regT0, regT0));
+#endif
+            lhsIsInt.link(this);
+            emitJumpSlowCaseIfNotImmediateInteger(regT2);
+        } else {
+            // !supportsFloatingPoint() => 2 SlowCases
+            emitJumpSlowCaseIfNotImmediateInteger(regT0);
+            emitJumpSlowCaseIfNotImmediateInteger(regT2);
+        }
+        emitFastArithImmToInt(regT2);
 #if !PLATFORM(X86)
         // Mask with 0x1f as per ecma-262 11.7.2 step 7.
         // On 32-bit x86 this is not necessary, since the shift anount is implicitly masked in the instruction.
-        and32(Imm32(0x1f), X86::ecx);
+        and32(Imm32(0x1f), regT2);
 #endif
 #if USE(ALTERNATE_JSIMMEDIATE)
-        rshift32(X86::ecx, X86::eax);
+        rshift32(regT2, regT0);
 #else
-        rshiftPtr(X86::ecx, X86::eax);
+        rshiftPtr(regT2, regT0);
 #endif
     }
 #if USE(ALTERNATE_JSIMMEDIATE)
-    emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+    emitFastArithIntToImmNoCheck(regT0, regT0);
 #else
-    orPtr(Imm32(JSImmediate::TagTypeInteger), X86::eax);
+    orPtr(Imm32(JSImmediate::TagTypeNumber), regT0);
 #endif
     emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_rshift(unsigned result, unsigned, unsigned op2, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_rshift(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    linkSlowCase(iter);
-    if (isOperandConstantImmediateInt(op2))
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
-    else {
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    JITStubCall stubCall(this, JITStubs::cti_op_rshift);
+
+    if (isOperandConstantImmediateInt(op2)) {
         linkSlowCase(iter);
-        emitPutJITStubArg(X86::ecx, 2);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(op2, regT2);
+    } else {
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+#else
+            linkSlowCaseIfNotJSCell(iter, op1);
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+#endif
+            // We're reloading op1 to regT0 as we can no longer guarantee that
+            // we have not munged the operand.  It may have already been shifted
+            // correctly, but it still will not have been tagged.
+            stubCall.addArgument(op1, regT0);
+            stubCall.addArgument(regT2);
+        } else {
+            linkSlowCase(iter);
+            linkSlowCase(iter);
+            stubCall.addArgument(regT0);
+            stubCall.addArgument(regT2);
+        }
     }
 
-    emitPutJITStubArg(X86::eax, 1);
-    emitCTICall(Interpreter::cti_op_rshift);
-    emitPutVirtualRegister(result);
+    stubCall.call(result);
 }
 
-void JIT::compileFastArith_op_bitand(unsigned result, unsigned op1, unsigned op2)
+void JIT::emit_op_jnless(Instruction* currentInstruction)
 {
-    if (isOperandConstantImmediateInt(op1)) {
-        emitGetVirtualRegister(op2, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+    unsigned op1 = currentInstruction[1].u.operand;
+    unsigned op2 = currentInstruction[2].u.operand;
+    unsigned target = currentInstruction[3].u.operand;
+
+    // We generate inline code for the following cases in the fast path:
+    // - int immediate to constant int immediate
+    // - constant int immediate to int immediate
+    // - int immediate to int immediate
+
+    if (isOperandConstantImmediateInt(op2)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        int32_t imm = JSImmediate::intValue(getConstantOperand(op1));
-        andPtr(Imm32(imm), X86::eax);
-        if (imm >= 0)
-            emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+        int32_t op2imm = getConstantOperandImmediateInt(op2);
 #else
-        andPtr(Imm32(static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op1)))), X86::eax);
+        int32_t op2imm = static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op2)));
 #endif
-    } else if (isOperandConstantImmediateInt(op2)) {
-        emitGetVirtualRegister(op1, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+        addJump(branch32(GreaterThanOrEqual, regT0, Imm32(op2imm)), target + 3);
+    } else if (isOperandConstantImmediateInt(op1)) {
+        emitGetVirtualRegister(op2, regT1);
+        emitJumpSlowCaseIfNotImmediateInteger(regT1);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        int32_t imm = JSImmediate::intValue(getConstantOperand(op2));
-        andPtr(Imm32(imm), X86::eax);
-        if (imm >= 0)
-            emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+        int32_t op1imm = getConstantOperandImmediateInt(op1);
 #else
-        andPtr(Imm32(static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op2)))), X86::eax);
+        int32_t op1imm = static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op1)));
 #endif
+        addJump(branch32(LessThanOrEqual, regT1, Imm32(op1imm)), target + 3);
     } else {
-        emitGetVirtualRegisters(op1, X86::eax, op2, X86::edx);
-        andPtr(X86::edx, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+        emitGetVirtualRegisters(op1, regT0, op2, regT1);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT1);
+
+        addJump(branch32(GreaterThanOrEqual, regT0, regT1), target + 3);
     }
-    emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_bitand(unsigned result, unsigned op1, unsigned op2, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_jnless(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    linkSlowCase(iter);
-    if (isOperandConstantImmediateInt(op1)) {
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArg(X86::eax, 2);
-    } else if (isOperandConstantImmediateInt(op2)) {
-        emitPutJITStubArg(X86::eax, 1);
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
+    unsigned op1 = currentInstruction[1].u.operand;
+    unsigned op2 = currentInstruction[2].u.operand;
+    unsigned target = currentInstruction[3].u.operand;
+
+    // We generate inline code for the following cases in the slow path:
+    // - floating-point number to constant int immediate
+    // - constant int immediate to floating-point number
+    // - floating-point number to floating-point number.
+
+    if (isOperandConstantImmediateInt(op2)) {
+        linkSlowCase(iter);
+
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT0);
+            addPtr(tagTypeNumberRegister, regT0);
+            movePtrToDouble(regT0, fpRegT0);
+#else
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1 = emitJumpIfNotJSCell(regT0);
+
+            Jump fail2 = checkStructure(regT0, m_globalData->numberStructure.get());
+            loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
+#endif
+            
+            int32_t op2imm = getConstantOperand(op2).getInt32Fast();;
+                    
+            move(Imm32(op2imm), regT1);
+            convertInt32ToDouble(regT1, fpRegT1);
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThanOrEqual, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnless));
+
+#if USE(ALTERNATE_JSIMMEDIATE)
+            fail1.link(this);
+#else
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1.link(this);
+            fail2.link(this);
+#endif
+        }
+
+        JITStubCall stubCall(this, JITStubs::cti_op_jless);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
+
+    } else if (isOperandConstantImmediateInt(op1)) {
+        linkSlowCase(iter);
+
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT1);
+            addPtr(tagTypeNumberRegister, regT1);
+            movePtrToDouble(regT1, fpRegT1);
+#else
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail1 = emitJumpIfNotJSCell(regT1);
+            
+            Jump fail2 = checkStructure(regT1, m_globalData->numberStructure.get());
+            loadDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT1);
+#endif
+            
+            int32_t op1imm = getConstantOperand(op1).getInt32Fast();;
+                    
+            move(Imm32(op1imm), regT0);
+            convertInt32ToDouble(regT0, fpRegT0);
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThanOrEqual, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnless));
+
+#if USE(ALTERNATE_JSIMMEDIATE)
+            fail1.link(this);
+#else
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail1.link(this);
+            fail2.link(this);
+#endif
+        }
+
+        JITStubCall stubCall(this, JITStubs::cti_op_jless);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(regT1);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
+
     } else {
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArg(X86::edx, 2);
-    }
-    emitCTICall(Interpreter::cti_op_bitand);
-    emitPutVirtualRegister(result);
-}
+        linkSlowCase(iter);
 
-void JIT::compileFastArith_op_mod(unsigned result, unsigned op1, unsigned op2)
-{
-    emitGetVirtualRegisters(op1, X86::eax, op2, X86::ecx);
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
-    emitJumpSlowCaseIfNotImmNum(X86::ecx);
+        if (supportsFloatingPoint()) {
 #if USE(ALTERNATE_JSIMMEDIATE)
-    addSlowCase(jePtr(X86::ecx, ImmPtr(JSValuePtr::encode(JSImmediate::zeroImmediate()))));
-    mod32(X86::ecx, X86::eax, X86::edx);
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT0);
+            Jump fail2 = emitJumpIfNotImmediateNumber(regT1);
+            Jump fail3 = emitJumpIfImmediateInteger(regT1);
+            addPtr(tagTypeNumberRegister, regT0);
+            addPtr(tagTypeNumberRegister, regT1);
+            movePtrToDouble(regT0, fpRegT0);
+            movePtrToDouble(regT1, fpRegT1);
 #else
-    emitFastArithDeTagImmediate(X86::eax);
-    addSlowCase(emitFastArithDeTagImmediateJumpIfZero(X86::ecx));
-    mod32(X86::ecx, X86::eax, X86::edx);
-    signExtend32ToPtr(X86::edx, X86::edx);
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1 = emitJumpIfNotJSCell(regT0);
+
+            Jump fail2;
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail2 = emitJumpIfNotJSCell(regT1);
+
+            Jump fail3 = checkStructure(regT0, m_globalData->numberStructure.get());
+            Jump fail4 = checkStructure(regT1, m_globalData->numberStructure.get());
+            loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
+            loadDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT1);
 #endif
-    emitFastArithReTagImmediate(X86::edx, X86::eax);
-    emitPutVirtualRegister(result);
-}
-void JIT::compileFastArithSlow_op_mod(unsigned result, unsigned, unsigned, Vector<SlowCaseEntry>::iterator& iter)
-{
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThanOrEqual, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnless));
+
 #if USE(ALTERNATE_JSIMMEDIATE)
-    linkSlowCase(iter);
-    linkSlowCase(iter);
-    linkSlowCase(iter);
+            fail1.link(this);
+            fail2.link(this);
+            fail3.link(this);
 #else
-    Jump notImm1 = getSlowCase(iter);
-    Jump notImm2 = getSlowCase(iter);
-    linkSlowCase(iter);
-    emitFastArithReTagImmediate(X86::eax, X86::eax);
-    emitFastArithReTagImmediate(X86::ecx, X86::ecx);
-    notImm1.link(this);
-    notImm2.link(this);
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1.link(this);
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail2.link(this);
+            fail3.link(this);
+            fail4.link(this);
 #endif
-    emitPutJITStubArg(X86::eax, 1);
-    emitPutJITStubArg(X86::ecx, 2);
-    emitCTICall(Interpreter::cti_op_mod);
-    emitPutVirtualRegister(result);
+        }
+
+        linkSlowCase(iter);
+        JITStubCall stubCall(this, JITStubs::cti_op_jless);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(regT1);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
+    }
 }
 
-void JIT::compileFastArith_op_add(Instruction* currentInstruction)
+void JIT::emit_op_jnlesseq(Instruction* currentInstruction)
 {
-    unsigned result = currentInstruction[1].u.operand;
-    unsigned op1 = currentInstruction[2].u.operand;
-    unsigned op2 = currentInstruction[3].u.operand;
+    unsigned op1 = currentInstruction[1].u.operand;
+    unsigned op2 = currentInstruction[2].u.operand;
+    unsigned target = currentInstruction[3].u.operand;
 
-    if (isOperandConstantImmediateInt(op1)) {
-        emitGetVirtualRegister(op2, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+    // We generate inline code for the following cases in the fast path:
+    // - int immediate to constant int immediate
+    // - constant int immediate to int immediate
+    // - int immediate to int immediate
+
+    if (isOperandConstantImmediateInt(op2)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        // FIXME: investigate performing a 31-bit add here (can we preserve upper bit & detect overflow from low word to high?)
-        //        (or, detect carry? - if const is positive, will only carry when overflowing from negative to positive?)
-        addSlowCase(joAdd32(Imm32(getConstantOperandImmediateInt(op1)), X86::eax));
-        emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+        int32_t op2imm = getConstantOperandImmediateInt(op2);
 #else
-        addSlowCase(joAdd32(Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), X86::eax));
-        signExtend32ToPtr(X86::eax, X86::eax);
+        int32_t op2imm = static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op2)));
 #endif
-        emitPutVirtualRegister(result);
-    } else if (isOperandConstantImmediateInt(op2)) {
-        emitGetVirtualRegister(op1, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+        addJump(branch32(GreaterThan, regT0, Imm32(op2imm)), target + 3);
+    } else if (isOperandConstantImmediateInt(op1)) {
+        emitGetVirtualRegister(op2, regT1);
+        emitJumpSlowCaseIfNotImmediateInteger(regT1);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        emitFastArithImmToInt(X86::eax);
-        addSlowCase(joAdd32(Imm32(getConstantOperandImmediateInt(op2)), X86::eax));
-        emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+        int32_t op1imm = getConstantOperandImmediateInt(op1);
 #else
-        addSlowCase(joAdd32(Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), X86::eax));
-        signExtend32ToPtr(X86::eax, X86::eax);
+        int32_t op1imm = static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op1)));
 #endif
-        emitPutVirtualRegister(result);
+        addJump(branch32(LessThan, regT1, Imm32(op1imm)), target + 3);
     } else {
-        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
-        if (types.first().mightBeNumber() && types.second().mightBeNumber())
-            compileBinaryArithOp(op_add, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
-        else {
-            emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-            emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
-            emitCTICall(Interpreter::cti_op_add);
-            emitPutVirtualRegister(result);
-        }
+        emitGetVirtualRegisters(op1, regT0, op2, regT1);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT1);
+
+        addJump(branch32(GreaterThan, regT0, regT1), target + 3);
     }
 }
-void JIT::compileFastArithSlow_op_add(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_jnlesseq(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    unsigned result = currentInstruction[1].u.operand;
-    unsigned op1 = currentInstruction[2].u.operand;
-    unsigned op2 = currentInstruction[3].u.operand;
+    unsigned op1 = currentInstruction[1].u.operand;
+    unsigned op2 = currentInstruction[2].u.operand;
+    unsigned target = currentInstruction[3].u.operand;
 
-    if (isOperandConstantImmediateInt(op1)) {
-#if USE(ALTERNATE_JSIMMEDIATE)
-        linkSlowCase(iter);
+    // We generate inline code for the following cases in the slow path:
+    // - floating-point number to constant int immediate
+    // - constant int immediate to floating-point number
+    // - floating-point number to floating-point number.
+
+    if (isOperandConstantImmediateInt(op2)) {
         linkSlowCase(iter);
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
+
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT0);
+            addPtr(tagTypeNumberRegister, regT0);
+            movePtrToDouble(regT0, fpRegT0);
 #else
-        Jump notImm = getSlowCase(iter);
-        linkSlowCase(iter);
-        sub32(Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), X86::eax);
-        notImm.link(this);
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArg(X86::eax, 2);
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1 = emitJumpIfNotJSCell(regT0);
+
+            Jump fail2 = checkStructure(regT0, m_globalData->numberStructure.get());
+            loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
 #endif
-        emitCTICall(Interpreter::cti_op_add);
-        emitPutVirtualRegister(result);
-    } else if (isOperandConstantImmediateInt(op2)) {
+            
+            int32_t op2imm = getConstantOperand(op2).getInt32Fast();;
+                    
+            move(Imm32(op2imm), regT1);
+            convertInt32ToDouble(regT1, fpRegT1);
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThan, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnlesseq));
+
 #if USE(ALTERNATE_JSIMMEDIATE)
-        linkSlowCase(iter);
-        linkSlowCase(iter);
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
+            fail1.link(this);
 #else
-        Jump notImm = getSlowCase(iter);
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1.link(this);
+            fail2.link(this);
+#endif
+        }
+
+        JITStubCall stubCall(this, JITStubs::cti_op_jlesseq);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
+
+    } else if (isOperandConstantImmediateInt(op1)) {
         linkSlowCase(iter);
-        sub32(Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), X86::eax);
-        notImm.link(this);
-        emitPutJITStubArg(X86::eax, 1);
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
+
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT1);
+            addPtr(tagTypeNumberRegister, regT1);
+            movePtrToDouble(regT1, fpRegT1);
+#else
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail1 = emitJumpIfNotJSCell(regT1);
+            
+            Jump fail2 = checkStructure(regT1, m_globalData->numberStructure.get());
+            loadDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT1);
 #endif
-        emitCTICall(Interpreter::cti_op_add);
-        emitPutVirtualRegister(result);
+            
+            int32_t op1imm = getConstantOperand(op1).getInt32Fast();;
+                    
+            move(Imm32(op1imm), regT0);
+            convertInt32ToDouble(regT0, fpRegT0);
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThan, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnlesseq));
+
+#if USE(ALTERNATE_JSIMMEDIATE)
+            fail1.link(this);
+#else
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail1.link(this);
+            fail2.link(this);
+#endif
+        }
+
+        JITStubCall stubCall(this, JITStubs::cti_op_jlesseq);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(regT1);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
+
     } else {
-        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
-        ASSERT(types.first().mightBeNumber() && types.second().mightBeNumber());
-        compileBinaryArithOpSlowCase(op_add, iter, result, op1, op2, types);
+        linkSlowCase(iter);
+
+        if (supportsFloatingPoint()) {
+#if USE(ALTERNATE_JSIMMEDIATE)
+            Jump fail1 = emitJumpIfNotImmediateNumber(regT0);
+            Jump fail2 = emitJumpIfNotImmediateNumber(regT1);
+            Jump fail3 = emitJumpIfImmediateInteger(regT1);
+            addPtr(tagTypeNumberRegister, regT0);
+            addPtr(tagTypeNumberRegister, regT1);
+            movePtrToDouble(regT0, fpRegT0);
+            movePtrToDouble(regT1, fpRegT1);
+#else
+            Jump fail1;
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1 = emitJumpIfNotJSCell(regT0);
+
+            Jump fail2;
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail2 = emitJumpIfNotJSCell(regT1);
+
+            Jump fail3 = checkStructure(regT0, m_globalData->numberStructure.get());
+            Jump fail4 = checkStructure(regT1, m_globalData->numberStructure.get());
+            loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
+            loadDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT1);
+#endif
+
+            emitJumpSlowToHot(branchDouble(DoubleLessThan, fpRegT1, fpRegT0), target + 3);
+
+            emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_jnlesseq));
+
+#if USE(ALTERNATE_JSIMMEDIATE)
+            fail1.link(this);
+            fail2.link(this);
+            fail3.link(this);
+#else
+            if (!m_codeBlock->isKnownNotImmediate(op1))
+                fail1.link(this);
+            if (!m_codeBlock->isKnownNotImmediate(op2))
+                fail2.link(this);
+            fail3.link(this);
+            fail4.link(this);
+#endif
+        }
+
+        linkSlowCase(iter);
+        JITStubCall stubCall(this, JITStubs::cti_op_jlesseq);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(regT1);
+        stubCall.call();
+        emitJumpSlowToHot(branchTest32(Zero, regT0), target + 3);
     }
 }
 
-void JIT::compileFastArith_op_mul(Instruction* currentInstruction)
+void JIT::emit_op_bitand(Instruction* currentInstruction)
 {
     unsigned result = currentInstruction[1].u.operand;
     unsigned op1 = currentInstruction[2].u.operand;
     unsigned op2 = currentInstruction[3].u.operand;
 
-    // For now, only plant a fast int case if the constant operand is greater than zero.
-    int32_t value;
-    if (isOperandConstantImmediateInt(op1) && ((value = getConstantOperandImmediateInt(op1)) > 0)) {
-        emitGetVirtualRegister(op2, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+    if (isOperandConstantImmediateInt(op1)) {
+        emitGetVirtualRegister(op2, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        addSlowCase(joMul32(Imm32(value), X86::eax, X86::eax));
+        int32_t imm = getConstantOperandImmediateInt(op1);
+        andPtr(Imm32(imm), regT0);
+        if (imm >= 0)
+            emitFastArithIntToImmNoCheck(regT0, regT0);
 #else
-        emitFastArithDeTagImmediate(X86::eax);
-        addSlowCase(joMul32(Imm32(value), X86::eax, X86::eax));
-        signExtend32ToPtr(X86::eax, X86::eax);
+        andPtr(Imm32(static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op1)))), regT0);
 #endif
-        emitFastArithReTagImmediate(X86::eax, X86::eax);
-        emitPutVirtualRegister(result);
-    } else if (isOperandConstantImmediateInt(op2) && ((value = getConstantOperandImmediateInt(op2)) > 0)) {
-        emitGetVirtualRegister(op1, X86::eax);
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
+    } else if (isOperandConstantImmediateInt(op2)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-        addSlowCase(joMul32(Imm32(value), X86::eax, X86::eax));
+        int32_t imm = getConstantOperandImmediateInt(op2);
+        andPtr(Imm32(imm), regT0);
+        if (imm >= 0)
+            emitFastArithIntToImmNoCheck(regT0, regT0);
 #else
-        emitFastArithDeTagImmediate(X86::eax);
-        addSlowCase(joMul32(Imm32(value), X86::eax, X86::eax));
-        signExtend32ToPtr(X86::eax, X86::eax);
+        andPtr(Imm32(static_cast<int32_t>(JSImmediate::rawValue(getConstantOperand(op2)))), regT0);
 #endif
-        emitFastArithReTagImmediate(X86::eax, X86::eax);
-        emitPutVirtualRegister(result);
-    } else
-        compileBinaryArithOp(op_mul, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
+    } else {
+        emitGetVirtualRegisters(op1, regT0, op2, regT1);
+        andPtr(regT1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+    }
+    emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_mul(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_bitand(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    int result = currentInstruction[1].u.operand;
-    int op1 = currentInstruction[2].u.operand;
-    int op2 = currentInstruction[3].u.operand;
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
 
-    if ((isOperandConstantImmediateInt(op1) && (getConstantOperandImmediateInt(op1) > 0))
-        || (isOperandConstantImmediateInt(op2) && (getConstantOperandImmediateInt(op2) > 0))) {
-        linkSlowCase(iter);
-        linkSlowCase(iter);
-        // There is an extra slow case for (op1 * -N) or (-N * op2), to check for 0 since this should produce a result of -0.
-        emitPutJITStubArgFromVirtualRegister(op1, 1, X86::ecx);
-        emitPutJITStubArgFromVirtualRegister(op2, 2, X86::ecx);
-        emitCTICall(Interpreter::cti_op_mul);
-        emitPutVirtualRegister(result);
-    } else
-        compileBinaryArithOpSlowCase(op_mul, iter, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
+    linkSlowCase(iter);
+    if (isOperandConstantImmediateInt(op1)) {
+        JITStubCall stubCall(this, JITStubs::cti_op_bitand);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(regT0);
+        stubCall.call(result);
+    } else if (isOperandConstantImmediateInt(op2)) {
+        JITStubCall stubCall(this, JITStubs::cti_op_bitand);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+    } else {
+        JITStubCall stubCall(this, JITStubs::cti_op_bitand);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(regT1);
+        stubCall.call(result);
+    }
 }
 
-void JIT::compileFastArith_op_post_inc(unsigned result, unsigned srcDst)
+void JIT::emit_op_post_inc(Instruction* currentInstruction)
 {
-    emitGetVirtualRegister(srcDst, X86::eax);
-    move(X86::eax, X86::edx);
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned srcDst = currentInstruction[2].u.operand;
+
+    emitGetVirtualRegister(srcDst, regT0);
+    move(regT0, regT1);
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-    addSlowCase(joAdd32(Imm32(1), X86::edx));
-    emitFastArithIntToImmNoCheck(X86::edx, X86::edx);
+    addSlowCase(branchAdd32(Overflow, Imm32(1), regT1));
+    emitFastArithIntToImmNoCheck(regT1, regT1);
 #else
-    addSlowCase(joAdd32(Imm32(1 << JSImmediate::IntegerPayloadShift), X86::edx));
-    signExtend32ToPtr(X86::edx, X86::edx);
+    addSlowCase(branchAdd32(Overflow, Imm32(1 << JSImmediate::IntegerPayloadShift), regT1));
+    signExtend32ToPtr(regT1, regT1);
 #endif
-    emitPutVirtualRegister(srcDst, X86::edx);
+    emitPutVirtualRegister(srcDst, regT1);
     emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_post_inc(unsigned result, unsigned srcDst, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_post_inc(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned srcDst = currentInstruction[2].u.operand;
+
     linkSlowCase(iter);
     linkSlowCase(iter);
-    emitPutJITStubArg(X86::eax, 1);
-    emitCTICall(Interpreter::cti_op_post_inc);
-    emitPutVirtualRegister(srcDst, X86::edx);
-    emitPutVirtualRegister(result);
+    JITStubCall stubCall(this, JITStubs::cti_op_post_inc);
+    stubCall.addArgument(regT0);
+    stubCall.addArgument(Imm32(srcDst));
+    stubCall.call(result);
 }
 
-void JIT::compileFastArith_op_post_dec(unsigned result, unsigned srcDst)
+void JIT::emit_op_post_dec(Instruction* currentInstruction)
 {
-    emitGetVirtualRegister(srcDst, X86::eax);
-    move(X86::eax, X86::edx);
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned srcDst = currentInstruction[2].u.operand;
+
+    emitGetVirtualRegister(srcDst, regT0);
+    move(regT0, regT1);
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-    addSlowCase(joSub32(Imm32(1), X86::edx));
-    emitFastArithIntToImmNoCheck(X86::edx, X86::edx);
+    addSlowCase(branchSub32(Zero, Imm32(1), regT1));
+    emitFastArithIntToImmNoCheck(regT1, regT1);
 #else
-    addSlowCase(joSub32(Imm32(1 << JSImmediate::IntegerPayloadShift), X86::edx));
-    signExtend32ToPtr(X86::edx, X86::edx);
+    addSlowCase(branchSub32(Zero, Imm32(1 << JSImmediate::IntegerPayloadShift), regT1));
+    signExtend32ToPtr(regT1, regT1);
 #endif
-    emitPutVirtualRegister(srcDst, X86::edx);
+    emitPutVirtualRegister(srcDst, regT1);
     emitPutVirtualRegister(result);
 }
-void JIT::compileFastArithSlow_op_post_dec(unsigned result, unsigned srcDst, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_post_dec(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned srcDst = currentInstruction[2].u.operand;
+
     linkSlowCase(iter);
     linkSlowCase(iter);
-    emitPutJITStubArg(X86::eax, 1);
-    emitCTICall(Interpreter::cti_op_post_dec);
-    emitPutVirtualRegister(srcDst, X86::edx);
-    emitPutVirtualRegister(result);
+    JITStubCall stubCall(this, JITStubs::cti_op_post_dec);
+    stubCall.addArgument(regT0);
+    stubCall.addArgument(Imm32(srcDst));
+    stubCall.call(result);
 }
 
-void JIT::compileFastArith_op_pre_inc(unsigned srcDst)
+void JIT::emit_op_pre_inc(Instruction* currentInstruction)
 {
-    emitGetVirtualRegister(srcDst, X86::eax);
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
+    unsigned srcDst = currentInstruction[1].u.operand;
+
+    emitGetVirtualRegister(srcDst, regT0);
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-    // FIXME: Could add ptr & specify int64; no need to re-sign-extend?
-    addSlowCase(joAdd32(Imm32(1), X86::eax));
-    emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+    addSlowCase(branchAdd32(Overflow, Imm32(1), regT0));
+    emitFastArithIntToImmNoCheck(regT0, regT0);
 #else
-    addSlowCase(joAdd32(Imm32(1 << JSImmediate::IntegerPayloadShift), X86::eax));
-    signExtend32ToPtr(X86::eax, X86::eax);
+    addSlowCase(branchAdd32(Overflow, Imm32(1 << JSImmediate::IntegerPayloadShift), regT0));
+    signExtend32ToPtr(regT0, regT0);
 #endif
     emitPutVirtualRegister(srcDst);
 }
-void JIT::compileFastArithSlow_op_pre_inc(unsigned srcDst, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_pre_inc(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    unsigned srcDst = currentInstruction[1].u.operand;
+
     Jump notImm = getSlowCase(iter);
     linkSlowCase(iter);
-    emitGetVirtualRegister(srcDst, X86::eax);
+    emitGetVirtualRegister(srcDst, regT0);
     notImm.link(this);
-    emitPutJITStubArg(X86::eax, 1);
-    emitCTICall(Interpreter::cti_op_pre_inc);
-    emitPutVirtualRegister(srcDst);
+    JITStubCall stubCall(this, JITStubs::cti_op_pre_inc);
+    stubCall.addArgument(regT0);
+    stubCall.call(srcDst);
 }
 
-void JIT::compileFastArith_op_pre_dec(unsigned srcDst)
+void JIT::emit_op_pre_dec(Instruction* currentInstruction)
 {
-    emitGetVirtualRegister(srcDst, X86::eax);
-    emitJumpSlowCaseIfNotImmNum(X86::eax);
+    unsigned srcDst = currentInstruction[1].u.operand;
+
+    emitGetVirtualRegister(srcDst, regT0);
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
 #if USE(ALTERNATE_JSIMMEDIATE)
-    addSlowCase(joSub32(Imm32(1), X86::eax));
-    emitFastArithIntToImmNoCheck(X86::eax, X86::eax);
+    addSlowCase(branchSub32(Zero, Imm32(1), regT0));
+    emitFastArithIntToImmNoCheck(regT0, regT0);
 #else
-    addSlowCase(joSub32(Imm32(1 << JSImmediate::IntegerPayloadShift), X86::eax));
-    signExtend32ToPtr(X86::eax, X86::eax);
+    addSlowCase(branchSub32(Zero, Imm32(1 << JSImmediate::IntegerPayloadShift), regT0));
+    signExtend32ToPtr(regT0, regT0);
 #endif
     emitPutVirtualRegister(srcDst);
 }
-void JIT::compileFastArithSlow_op_pre_dec(unsigned srcDst, Vector<SlowCaseEntry>::iterator& iter)
+
+void JIT::emitSlow_op_pre_dec(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    unsigned srcDst = currentInstruction[1].u.operand;
+
     Jump notImm = getSlowCase(iter);
     linkSlowCase(iter);
-    emitGetVirtualRegister(srcDst, X86::eax);
+    emitGetVirtualRegister(srcDst, regT0);
     notImm.link(this);
-    emitPutJITStubArg(X86::eax, 1);
-    emitCTICall(Interpreter::cti_op_pre_dec);
-    emitPutVirtualRegister(srcDst);
+    JITStubCall stubCall(this, JITStubs::cti_op_pre_dec);
+    stubCall.addArgument(regT0);
+    stubCall.call(srcDst);
 }
 
+/* ------------------------------ BEGIN: OP_MOD ------------------------------ */
+
+#if PLATFORM(X86) || PLATFORM(X86_64)
+
+void JIT::emit_op_mod(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    emitGetVirtualRegisters(op1, X86::eax, op2, X86::ecx);
+    emitJumpSlowCaseIfNotImmediateInteger(X86::eax);
+    emitJumpSlowCaseIfNotImmediateInteger(X86::ecx);
+#if USE(ALTERNATE_JSIMMEDIATE)
+    addSlowCase(branchPtr(Equal, X86::ecx, ImmPtr(JSValue::encode(jsNumber(m_globalData, 0)))));
+    m_assembler.cdq();
+    m_assembler.idivl_r(X86::ecx);
+#else
+    emitFastArithDeTagImmediate(X86::eax);
+    addSlowCase(emitFastArithDeTagImmediateJumpIfZero(X86::ecx));
+    m_assembler.cdq();
+    m_assembler.idivl_r(X86::ecx);
+    signExtend32ToPtr(X86::edx, X86::edx);
+#endif
+    emitFastArithReTagImmediate(X86::edx, X86::eax);
+    emitPutVirtualRegister(result);
+}
+
+void JIT::emitSlow_op_mod(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    unsigned result = currentInstruction[1].u.operand;
+
+#if USE(ALTERNATE_JSIMMEDIATE)
+    linkSlowCase(iter);
+    linkSlowCase(iter);
+    linkSlowCase(iter);
+#else
+    Jump notImm1 = getSlowCase(iter);
+    Jump notImm2 = getSlowCase(iter);
+    linkSlowCase(iter);
+    emitFastArithReTagImmediate(X86::eax, X86::eax);
+    emitFastArithReTagImmediate(X86::ecx, X86::ecx);
+    notImm1.link(this);
+    notImm2.link(this);
+#endif
+    JITStubCall stubCall(this, JITStubs::cti_op_mod);
+    stubCall.addArgument(X86::eax);
+    stubCall.addArgument(X86::ecx);
+    stubCall.call(result);
+}
+
+#else // PLATFORM(X86) || PLATFORM(X86_64)
+
+void JIT::emit_op_mod(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    JITStubCall stubCall(this, JITStubs::cti_op_mod);
+    stubCall.addArgument(op1, regT2);
+    stubCall.addArgument(op2, regT2);
+    stubCall.call(result);
+}
+
+void JIT::emitSlow_op_mod(Instruction*, Vector<SlowCaseEntry>::iterator&)
+{
+    ASSERT_NOT_REACHED();
+}
+
+#endif // PLATFORM(X86) || PLATFORM(X86_64)
+
+/* ------------------------------ END: OP_MOD ------------------------------ */
 
 #if !ENABLE(JIT_OPTIMIZE_ARITHMETIC)
 
-void JIT::compileBinaryArithOp(OpcodeID opcodeID, unsigned dst, unsigned src1, unsigned src2, OperandTypes)
+/* ------------------------------ BEGIN: !ENABLE(JIT_OPTIMIZE_ARITHMETIC) (OP_ADD, OP_SUB, OP_MUL) ------------------------------ */
+
+void JIT::emit_op_add(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    JITStubCall stubCall(this, JITStubs::cti_op_add);
+    stubCall.addArgument(op1, regT2);
+    stubCall.addArgument(op2, regT2);
+    stubCall.call(result);
+}
+
+void JIT::emitSlow_op_add(Instruction*, Vector<SlowCaseEntry>::iterator&)
+{
+    ASSERT_NOT_REACHED();
+}
+
+void JIT::emit_op_mul(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    JITStubCall stubCall(this, JITStubs::cti_op_mul);
+    stubCall.addArgument(op1, regT2);
+    stubCall.addArgument(op2, regT2);
+    stubCall.call(result);
+}
+
+void JIT::emitSlow_op_mul(Instruction*, Vector<SlowCaseEntry>::iterator&)
+{
+    ASSERT_NOT_REACHED();
+}
+
+void JIT::emit_op_sub(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    JITStubCall stubCall(this, JITStubs::cti_op_sub);
+    stubCall.addArgument(op1, regT2);
+    stubCall.addArgument(op2, regT2);
+    stubCall.call(result);
+}
+
+void JIT::emitSlow_op_sub(Instruction*, Vector<SlowCaseEntry>::iterator&)
+{
+    ASSERT_NOT_REACHED();
+}
+
+#elif USE(ALTERNATE_JSIMMEDIATE) // *AND* ENABLE(JIT_OPTIMIZE_ARITHMETIC)
+
+/* ------------------------------ BEGIN: USE(ALTERNATE_JSIMMEDIATE) (OP_ADD, OP_SUB, OP_MUL) ------------------------------ */
+
+void JIT::compileBinaryArithOp(OpcodeID opcodeID, unsigned, unsigned op1, unsigned op2, OperandTypes)
 {
-    emitPutJITStubArgFromVirtualRegister(src1, 1, X86::ecx);
-    emitPutJITStubArgFromVirtualRegister(src2, 2, X86::ecx);
+    emitGetVirtualRegisters(op1, regT0, op2, regT1);
+    emitJumpSlowCaseIfNotImmediateInteger(regT0);
+    emitJumpSlowCaseIfNotImmediateInteger(regT1);
     if (opcodeID == op_add)
-        emitCTICall(Interpreter::cti_op_add);
+        addSlowCase(branchAdd32(Overflow, regT1, regT0));
     else if (opcodeID == op_sub)
-        emitCTICall(Interpreter::cti_op_sub);
+        addSlowCase(branchSub32(Overflow, regT1, regT0));
     else {
         ASSERT(opcodeID == op_mul);
-        emitCTICall(Interpreter::cti_op_mul);
+        addSlowCase(branchMul32(Overflow, regT1, regT0));
+        addSlowCase(branchTest32(Zero, regT0));
     }
-    emitPutVirtualRegister(dst);
+    emitFastArithIntToImmNoCheck(regT0, regT0);
 }
 
-void JIT::compileBinaryArithOpSlowCase(OpcodeID, Vector<SlowCaseEntry>::iterator&, unsigned, unsigned, unsigned, OperandTypes)
+void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>::iterator& iter, unsigned result, unsigned op1, unsigned, OperandTypes types)
 {
-    ASSERT_NOT_REACHED();
+    // We assume that subtracting TagTypeNumber is equivalent to adding DoubleEncodeOffset.
+    COMPILE_ASSERT(((JSImmediate::TagTypeNumber + JSImmediate::DoubleEncodeOffset) == 0), TagTypeNumber_PLUS_DoubleEncodeOffset_EQUALS_0);
+
+    Jump notImm1 = getSlowCase(iter);
+    Jump notImm2 = getSlowCase(iter);
+
+    linkSlowCase(iter); // Integer overflow case - we could handle this in JIT code, but this is likely rare.
+    if (opcodeID == op_mul) // op_mul has an extra slow case to handle 0 * negative number.
+        linkSlowCase(iter);
+    emitGetVirtualRegister(op1, regT0);
+
+    Label stubFunctionCall(this);
+    JITStubCall stubCall(this, opcodeID == op_add ? JITStubs::cti_op_add : opcodeID == op_sub ? JITStubs::cti_op_sub : JITStubs::cti_op_mul);
+    stubCall.addArgument(regT0);
+    stubCall.addArgument(regT1);
+    stubCall.call(result);
+    Jump end = jump();
+
+    // if we get here, eax is not an int32, edx not yet checked.
+    notImm1.link(this);
+    if (!types.first().definitelyIsNumber())
+        emitJumpIfNotImmediateNumber(regT0).linkTo(stubFunctionCall, this);
+    if (!types.second().definitelyIsNumber())
+        emitJumpIfNotImmediateNumber(regT1).linkTo(stubFunctionCall, this);
+    addPtr(tagTypeNumberRegister, regT0);
+    movePtrToDouble(regT0, fpRegT1);
+    Jump op2isDouble = emitJumpIfNotImmediateInteger(regT1);
+    convertInt32ToDouble(regT1, fpRegT2);
+    Jump op2wasInteger = jump();
+
+    // if we get here, eax IS an int32, edx is not.
+    notImm2.link(this);
+    if (!types.second().definitelyIsNumber())
+        emitJumpIfNotImmediateNumber(regT1).linkTo(stubFunctionCall, this);
+    convertInt32ToDouble(regT0, fpRegT1);
+    op2isDouble.link(this);
+    addPtr(tagTypeNumberRegister, regT1);
+    movePtrToDouble(regT1, fpRegT2);
+    op2wasInteger.link(this);
+
+    if (opcodeID == op_add)
+        addDouble(fpRegT2, fpRegT1);
+    else if (opcodeID == op_sub)
+        subDouble(fpRegT2, fpRegT1);
+    else {
+        ASSERT(opcodeID == op_mul);
+        mulDouble(fpRegT2, fpRegT1);
+    }
+    moveDoubleToPtr(fpRegT1, regT0);
+    subPtr(tagTypeNumberRegister, regT0);
+    emitPutVirtualRegister(result, regT0);
+
+    end.link(this);
 }
 
-#else
+void JIT::emit_op_add(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
 
-typedef X86Assembler::JmpSrc JmpSrc;
-typedef X86Assembler::JmpDst JmpDst;
-typedef X86Assembler::XMMRegisterID XMMRegisterID;
+    if (!types.first().mightBeNumber() || !types.second().mightBeNumber()) {
+        JITStubCall stubCall(this, JITStubs::cti_op_add);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+        return;
+    }
 
-#if PLATFORM(MAC)
+    if (isOperandConstantImmediateInt(op1)) {
+        emitGetVirtualRegister(op2, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op1)), regT0));
+        emitFastArithIntToImmNoCheck(regT0, regT0);
+    } else if (isOperandConstantImmediateInt(op2)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op2)), regT0));
+        emitFastArithIntToImmNoCheck(regT0, regT0);
+    } else
+        compileBinaryArithOp(op_add, result, op1, op2, types);
+
+    emitPutVirtualRegister(result);
+}
 
-static inline bool isSSE2Present()
+void JIT::emitSlow_op_add(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    return true; // All X86 Macs are guaranteed to support at least SSE2
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    if (isOperandConstantImmediateInt(op1) || isOperandConstantImmediateInt(op2)) {
+        linkSlowCase(iter);
+        linkSlowCase(iter);
+        JITStubCall stubCall(this, JITStubs::cti_op_add);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+    } else
+        compileBinaryArithOpSlowCase(op_add, iter, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
 }
 
-#else
+void JIT::emit_op_mul(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
 
-static bool isSSE2Present()
-{
-    static const int SSE2FeatureBit = 1 << 26;
-    struct SSE2Check {
-        SSE2Check()
-        {
-            int flags;
-#if COMPILER(MSVC)
-            _asm {
-                mov eax, 1 // cpuid function 1 gives us the standard feature set
-                cpuid;
-                mov flags, edx;
-            }
-#else
-            flags = 0;
-            // FIXME: Add GCC code to do above asm
-#endif
-            present = (flags & SSE2FeatureBit) != 0;
-        }
-        bool present;
-    };
-    static SSE2Check check;
-    return check.present;
+    // For now, only plant a fast int case if the constant operand is greater than zero.
+    int32_t value;
+    if (isOperandConstantImmediateInt(op1) && ((value = getConstantOperandImmediateInt(op1)) > 0)) {
+        emitGetVirtualRegister(op2, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchMul32(Overflow, Imm32(value), regT0, regT0));
+        emitFastArithReTagImmediate(regT0, regT0);
+    } else if (isOperandConstantImmediateInt(op2) && ((value = getConstantOperandImmediateInt(op2)) > 0)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchMul32(Overflow, Imm32(value), regT0, regT0));
+        emitFastArithReTagImmediate(regT0, regT0);
+    } else
+        compileBinaryArithOp(op_mul, result, op1, op2, types);
+
+    emitPutVirtualRegister(result);
 }
 
-#endif
+void JIT::emitSlow_op_mul(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
 
-/*
-  This is required since number representation is canonical - values representable as a JSImmediate should not be stored in a JSNumberCell.
-  
-  In the common case, the double value from 'xmmSource' is written to the reusable JSNumberCell pointed to by 'jsNumberCell', then 'jsNumberCell'
-  is written to the output SF Register 'dst', and then a jump is planted (stored into *wroteJSNumberCell).
-  
-  However if the value from xmmSource is representable as a JSImmediate, then the JSImmediate value will be written to the output, and flow
-  control will fall through from the code planted.
-*/
-void JIT::putDoubleResultToJSNumberCellOrJSImmediate(X86::XMMRegisterID xmmSource, X86::RegisterID jsNumberCell, unsigned dst, JmpSrc* wroteJSNumberCell,  X86::XMMRegisterID tempXmm, X86::RegisterID tempReg1, X86::RegisterID tempReg2)
-{
-    // convert (double -> JSImmediate -> double), and check if the value is unchanged - in which case the value is representable as a JSImmediate.
-    __ cvttsd2si_rr(xmmSource, tempReg1);
-    __ addl_rr(tempReg1, tempReg1);
-    __ sarl_i8r(1, tempReg1);
-    __ cvtsi2sd_rr(tempReg1, tempXmm);
-    // Compare & branch if immediate. 
-    __ ucomis_rr(tempXmm, xmmSource);
-    JmpSrc resultIsImm = __ je();
-    JmpDst resultLookedLikeImmButActuallyIsnt = __ label();
-    
-    // Store the result to the JSNumberCell and jump.
-    __ movsd_rm(xmmSource, FIELD_OFFSET(JSNumberCell, m_value), jsNumberCell);
-    if (jsNumberCell != X86::eax)
-        __ movl_rr(jsNumberCell, X86::eax);
-    emitPutVirtualRegister(dst);
-    *wroteJSNumberCell = __ jmp();
-
-    __ link(resultIsImm, __ label());
-    // value == (double)(JSImmediate)value... or at least, it looks that way...
-    // ucomi will report that (0 == -0), and will report true if either input in NaN (result is unordered).
-    __ link(__ jp(), resultLookedLikeImmButActuallyIsnt); // Actually was a NaN
-    __ pextrw_irr(3, xmmSource, tempReg2);
-    __ cmpl_ir(0x8000, tempReg2);
-    __ link(__ je(), resultLookedLikeImmButActuallyIsnt); // Actually was -0
-    // Yes it really really really is representable as a JSImmediate.
-    emitFastArithIntToImmNoCheck(tempReg1, X86::eax);
-    emitPutVirtualRegister(dst);
+    if ((isOperandConstantImmediateInt(op1) && (getConstantOperandImmediateInt(op1) > 0))
+        || (isOperandConstantImmediateInt(op2) && (getConstantOperandImmediateInt(op2) > 0))) {
+        linkSlowCase(iter);
+        linkSlowCase(iter);
+        // There is an extra slow case for (op1 * -N) or (-N * op2), to check for 0 since this should produce a result of -0.
+        JITStubCall stubCall(this, JITStubs::cti_op_mul);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+    } else
+        compileBinaryArithOpSlowCase(op_mul, iter, result, op1, op2, types);
 }
 
+void JIT::emit_op_sub(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
+
+    compileBinaryArithOp(op_sub, result, op1, op2, types);
+
+    emitPutVirtualRegister(result);
+}
+
+void JIT::emitSlow_op_sub(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+    OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
+
+    compileBinaryArithOpSlowCase(op_sub, iter, result, op1, op2, types);
+}
+
+#else // !ENABLE(JIT_OPTIMIZE_ARITHMETIC)
+
+/* ------------------------------ BEGIN: !ENABLE(JIT_OPTIMIZE_ARITHMETIC) (OP_ADD, OP_SUB, OP_MUL) ------------------------------ */
+
 void JIT::compileBinaryArithOp(OpcodeID opcodeID, unsigned dst, unsigned src1, unsigned src2, OperandTypes types)
 {
     Structure* numberStructure = m_globalData->numberStructure.get();
-    JmpSrc wasJSNumberCell1;
-    JmpSrc wasJSNumberCell1b;
-    JmpSrc wasJSNumberCell2;
-    JmpSrc wasJSNumberCell2b;
+    Jump wasJSNumberCell1;
+    Jump wasJSNumberCell2;
 
-    emitGetVirtualRegisters(src1, X86::eax, src2, X86::edx);
+    emitGetVirtualRegisters(src1, regT0, src2, regT1);
 
-    if (types.second().isReusable() && isSSE2Present()) {
+    if (types.second().isReusable() && supportsFloatingPoint()) {
         ASSERT(types.second().mightBeNumber());
 
         // Check op2 is a number
-        __ testl_i32r(JSImmediate::TagTypeInteger, X86::edx);
-        JmpSrc op2imm = __ jne();
+        Jump op2imm = emitJumpIfImmediateInteger(regT1);
         if (!types.second().definitelyIsNumber()) {
-            emitJumpSlowCaseIfNotJSCell(X86::edx, src2);
-            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::edx);
-            addSlowCase(__ jne());
+            emitJumpSlowCaseIfNotJSCell(regT1, src2);
+            addSlowCase(checkStructure(regT1, numberStructure));
         }
 
         // (1) In this case src2 is a reusable number cell.
         //     Slow case if src1 is not a number type.
-        __ testl_i32r(JSImmediate::TagTypeInteger, X86::eax);
-        JmpSrc op1imm = __ jne();
+        Jump op1imm = emitJumpIfImmediateInteger(regT0);
         if (!types.first().definitelyIsNumber()) {
-            emitJumpSlowCaseIfNotJSCell(X86::eax, src1);
-            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::eax);
-            addSlowCase(__ jne());
+            emitJumpSlowCaseIfNotJSCell(regT0, src1);
+            addSlowCase(checkStructure(regT0, numberStructure));
         }
 
         // (1a) if we get here, src1 is also a number cell
-        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::eax, X86::xmm0);
-        JmpSrc loadedDouble = __ jmp();
+        loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
+        Jump loadedDouble = jump();
         // (1b) if we get here, src1 is an immediate
-        __ link(op1imm, __ label());
-        emitFastArithImmToInt(X86::eax);
-        __ cvtsi2sd_rr(X86::eax, X86::xmm0);
+        op1imm.link(this);
+        emitFastArithImmToInt(regT0);
+        convertInt32ToDouble(regT0, fpRegT0);
         // (1c) 
-        __ link(loadedDouble, __ label());
+        loadedDouble.link(this);
         if (opcodeID == op_add)
-            __ addsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
+            addDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
         else if (opcodeID == op_sub)
-            __ subsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
+            subDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
         else {
             ASSERT(opcodeID == op_mul);
-            __ mulsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm0);
+            mulDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
         }
 
-        putDoubleResultToJSNumberCellOrJSImmediate(X86::xmm0, X86::edx, dst, &wasJSNumberCell2, X86::xmm1, X86::ecx, X86::eax);
-        wasJSNumberCell2b = __ jmp();
+        // Store the result to the JSNumberCell and jump.
+        storeDouble(fpRegT0, Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)));
+        move(regT1, regT0);
+        emitPutVirtualRegister(dst);
+        wasJSNumberCell2 = jump();
 
         // (2) This handles cases where src2 is an immediate number.
         //     Two slow cases - either src1 isn't an immediate, or the subtract overflows.
-        __ link(op2imm, __ label());
-        emitJumpSlowCaseIfNotImmNum(X86::eax);
-    } else if (types.first().isReusable() && isSSE2Present()) {
+        op2imm.link(this);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+    } else if (types.first().isReusable() && supportsFloatingPoint()) {
         ASSERT(types.first().mightBeNumber());
 
         // Check op1 is a number
-        __ testl_i32r(JSImmediate::TagTypeInteger, X86::eax);
-        JmpSrc op1imm = __ jne();
+        Jump op1imm = emitJumpIfImmediateInteger(regT0);
         if (!types.first().definitelyIsNumber()) {
-            emitJumpSlowCaseIfNotJSCell(X86::eax, src1);
-            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::eax);
-            addSlowCase(__ jne());
+            emitJumpSlowCaseIfNotJSCell(regT0, src1);
+            addSlowCase(checkStructure(regT0, numberStructure));
         }
 
         // (1) In this case src1 is a reusable number cell.
         //     Slow case if src2 is not a number type.
-        __ testl_i32r(JSImmediate::TagTypeInteger, X86::edx);
-        JmpSrc op2imm = __ jne();
+        Jump op2imm = emitJumpIfImmediateInteger(regT1);
         if (!types.second().definitelyIsNumber()) {
-            emitJumpSlowCaseIfNotJSCell(X86::edx, src2);
-            __ cmpl_im(reinterpret_cast<unsigned>(numberStructure), FIELD_OFFSET(JSCell, m_structure), X86::edx);
-            addSlowCase(__ jne());
+            emitJumpSlowCaseIfNotJSCell(regT1, src2);
+            addSlowCase(checkStructure(regT1, numberStructure));
         }
 
         // (1a) if we get here, src2 is also a number cell
-        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::edx, X86::xmm1);
-        JmpSrc loadedDouble = __ jmp();
+        loadDouble(Address(regT1, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT1);
+        Jump loadedDouble = jump();
         // (1b) if we get here, src2 is an immediate
-        __ link(op2imm, __ label());
-        emitFastArithImmToInt(X86::edx);
-        __ cvtsi2sd_rr(X86::edx, X86::xmm1);
+        op2imm.link(this);
+        emitFastArithImmToInt(regT1);
+        convertInt32ToDouble(regT1, fpRegT1);
         // (1c) 
-        __ link(loadedDouble, __ label());
-        __ movsd_mr(FIELD_OFFSET(JSNumberCell, m_value), X86::eax, X86::xmm0);
+        loadedDouble.link(this);
+        loadDouble(Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)), fpRegT0);
         if (opcodeID == op_add)
-            __ addsd_rr(X86::xmm1, X86::xmm0);
+            addDouble(fpRegT1, fpRegT0);
         else if (opcodeID == op_sub)
-            __ subsd_rr(X86::xmm1, X86::xmm0);
+            subDouble(fpRegT1, fpRegT0);
         else {
             ASSERT(opcodeID == op_mul);
-            __ mulsd_rr(X86::xmm1, X86::xmm0);
+            mulDouble(fpRegT1, fpRegT0);
         }
-        __ movsd_rm(X86::xmm0, FIELD_OFFSET(JSNumberCell, m_value), X86::eax);
+        storeDouble(fpRegT0, Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)));
         emitPutVirtualRegister(dst);
 
-        putDoubleResultToJSNumberCellOrJSImmediate(X86::xmm0, X86::eax, dst, &wasJSNumberCell1, X86::xmm1, X86::ecx, X86::edx);
-        wasJSNumberCell1b = __ jmp();
+        // Store the result to the JSNumberCell and jump.
+        storeDouble(fpRegT0, Address(regT0, FIELD_OFFSET(JSNumberCell, m_value)));
+        emitPutVirtualRegister(dst);
+        wasJSNumberCell1 = jump();
 
         // (2) This handles cases where src1 is an immediate number.
         //     Two slow cases - either src2 isn't an immediate, or the subtract overflows.
-        __ link(op1imm, __ label());
-        emitJumpSlowCaseIfNotImmNum(X86::edx);
+        op1imm.link(this);
+        emitJumpSlowCaseIfNotImmediateInteger(regT1);
     } else
-        emitJumpSlowCaseIfNotImmNums(X86::eax, X86::edx, X86::ecx);
+        emitJumpSlowCaseIfNotImmediateIntegers(regT0, regT1, regT2);
 
     if (opcodeID == op_add) {
-        emitFastArithDeTagImmediate(X86::eax);
-        __ addl_rr(X86::edx, X86::eax);
-        addSlowCase(__ jo());
+        emitFastArithDeTagImmediate(regT0);
+        addSlowCase(branchAdd32(Overflow, regT1, regT0));
     } else  if (opcodeID == op_sub) {
-        __ subl_rr(X86::edx, X86::eax);
-        addSlowCase(__ jo());
-        signExtend32ToPtr(X86::eax, X86::eax);
-        emitFastArithReTagImmediate(X86::eax, X86::eax);
+        addSlowCase(branchSub32(Overflow, regT1, regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitFastArithReTagImmediate(regT0, regT0);
     } else {
         ASSERT(opcodeID == op_mul);
         // convert eax & edx from JSImmediates to ints, and check if either are zero
-        emitFastArithImmToInt(X86::edx);
-        JmpSrc op1Zero = emitFastArithDeTagImmediateJumpIfZero(X86::eax);
-        __ testl_rr(X86::edx, X86::edx);
-        JmpSrc op2NonZero = __ jne();
-        __ link(op1Zero, __ label());
+        emitFastArithImmToInt(regT1);
+        Jump op1Zero = emitFastArithDeTagImmediateJumpIfZero(regT0);
+        Jump op2NonZero = branchTest32(NonZero, regT1);
+        op1Zero.link(this);
         // if either input is zero, add the two together, and check if the result is < 0.
         // If it is, we have a problem (N < 0), (N * 0) == -0, not representatble as a JSImmediate. 
-        __ movl_rr(X86::eax, X86::ecx);
-        __ addl_rr(X86::edx, X86::ecx);
-        addSlowCase(__ js());
+        move(regT0, regT2);
+        addSlowCase(branchAdd32(Signed, regT1, regT2));
         // Skip the above check if neither input is zero
-        __ link(op2NonZero, __ label());
-        __ imull_rr(X86::edx, X86::eax);
-        addSlowCase(__ jo());
-        signExtend32ToPtr(X86::eax, X86::eax);
-        emitFastArithReTagImmediate(X86::eax, X86::eax);
+        op2NonZero.link(this);
+        addSlowCase(branchMul32(Overflow, regT1, regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitFastArithReTagImmediate(regT0, regT0);
     }
     emitPutVirtualRegister(dst);
 
-    if (types.second().isReusable() && isSSE2Present()) {
-        __ link(wasJSNumberCell2, __ label());
-        __ link(wasJSNumberCell2b, __ label());
-    }
-    else if (types.first().isReusable() && isSSE2Present()) {
-        __ link(wasJSNumberCell1, __ label());
-        __ link(wasJSNumberCell1b, __ label());
-    }
+    if (types.second().isReusable() && supportsFloatingPoint())
+        wasJSNumberCell2.link(this);
+    else if (types.first().isReusable() && supportsFloatingPoint())
+        wasJSNumberCell1.link(this);
 }
 
 void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>::iterator& iter, unsigned dst, unsigned src1, unsigned src2, OperandTypes types)
 {
     linkSlowCase(iter);
-    if (types.second().isReusable() && isSSE2Present()) {
+    if (types.second().isReusable() && supportsFloatingPoint()) {
         if (!types.first().definitelyIsNumber()) {
             linkSlowCaseIfNotJSCell(iter, src1);
             linkSlowCase(iter);
@@ -733,7 +1227,7 @@ void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>:
             linkSlowCaseIfNotJSCell(iter, src2);
             linkSlowCase(iter);
         }
-    } else if (types.first().isReusable() && isSSE2Present()) {
+    } else if (types.first().isReusable() && supportsFloatingPoint()) {
         if (!types.first().definitelyIsNumber()) {
             linkSlowCaseIfNotJSCell(iter, src1);
             linkSlowCase(iter);
@@ -749,20 +1243,134 @@ void JIT::compileBinaryArithOpSlowCase(OpcodeID opcodeID, Vector<SlowCaseEntry>:
     if (opcodeID == op_mul)
         linkSlowCase(iter);
 
-    emitPutJITStubArgFromVirtualRegister(src1, 1, X86::ecx);
-    emitPutJITStubArgFromVirtualRegister(src2, 2, X86::ecx);
-    if (opcodeID == op_add)
-        emitCTICall(Interpreter::cti_op_add);
-    else if (opcodeID == op_sub)
-        emitCTICall(Interpreter::cti_op_sub);
-    else {
-        ASSERT(opcodeID == op_mul);
-        emitCTICall(Interpreter::cti_op_mul);
+    JITStubCall stubCall(this, opcodeID == op_add ? JITStubs::cti_op_add : opcodeID == op_sub ? JITStubs::cti_op_sub : JITStubs::cti_op_mul);
+    stubCall.addArgument(src1, regT2);
+    stubCall.addArgument(src2, regT2);
+    stubCall.call(dst);
+}
+
+void JIT::emit_op_add(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    if (isOperandConstantImmediateInt(op1)) {
+        emitGetVirtualRegister(op2, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitPutVirtualRegister(result);
+    } else if (isOperandConstantImmediateInt(op2)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        addSlowCase(branchAdd32(Overflow, Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitPutVirtualRegister(result);
+    } else {
+        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
+        if (types.first().mightBeNumber() && types.second().mightBeNumber())
+            compileBinaryArithOp(op_add, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
+        else {
+            JITStubCall stubCall(this, JITStubs::cti_op_add);
+            stubCall.addArgument(op1, regT2);
+            stubCall.addArgument(op2, regT2);
+            stubCall.call(result);
+        }
     }
-    emitPutVirtualRegister(dst);
 }
 
-#endif
+void JIT::emitSlow_op_add(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    if (isOperandConstantImmediateInt(op1)) {
+        Jump notImm = getSlowCase(iter);
+        linkSlowCase(iter);
+        sub32(Imm32(getConstantOperandImmediateInt(op1) << JSImmediate::IntegerPayloadShift), regT0);
+        notImm.link(this);
+        JITStubCall stubCall(this, JITStubs::cti_op_add);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(regT0);
+        stubCall.call(result);
+    } else if (isOperandConstantImmediateInt(op2)) {
+        Jump notImm = getSlowCase(iter);
+        linkSlowCase(iter);
+        sub32(Imm32(getConstantOperandImmediateInt(op2) << JSImmediate::IntegerPayloadShift), regT0);
+        notImm.link(this);
+        JITStubCall stubCall(this, JITStubs::cti_op_add);
+        stubCall.addArgument(regT0);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+    } else {
+        OperandTypes types = OperandTypes::fromInt(currentInstruction[4].u.operand);
+        ASSERT(types.first().mightBeNumber() && types.second().mightBeNumber());
+        compileBinaryArithOpSlowCase(op_add, iter, result, op1, op2, types);
+    }
+}
+
+void JIT::emit_op_mul(Instruction* currentInstruction)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    // For now, only plant a fast int case if the constant operand is greater than zero.
+    int32_t value;
+    if (isOperandConstantImmediateInt(op1) && ((value = getConstantOperandImmediateInt(op1)) > 0)) {
+        emitGetVirtualRegister(op2, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        emitFastArithDeTagImmediate(regT0);
+        addSlowCase(branchMul32(Overflow, Imm32(value), regT0, regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitFastArithReTagImmediate(regT0, regT0);
+        emitPutVirtualRegister(result);
+    } else if (isOperandConstantImmediateInt(op2) && ((value = getConstantOperandImmediateInt(op2)) > 0)) {
+        emitGetVirtualRegister(op1, regT0);
+        emitJumpSlowCaseIfNotImmediateInteger(regT0);
+        emitFastArithDeTagImmediate(regT0);
+        addSlowCase(branchMul32(Overflow, Imm32(value), regT0, regT0));
+        signExtend32ToPtr(regT0, regT0);
+        emitFastArithReTagImmediate(regT0, regT0);
+        emitPutVirtualRegister(result);
+    } else
+        compileBinaryArithOp(op_mul, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
+}
+
+void JIT::emitSlow_op_mul(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    unsigned result = currentInstruction[1].u.operand;
+    unsigned op1 = currentInstruction[2].u.operand;
+    unsigned op2 = currentInstruction[3].u.operand;
+
+    if ((isOperandConstantImmediateInt(op1) && (getConstantOperandImmediateInt(op1) > 0))
+        || (isOperandConstantImmediateInt(op2) && (getConstantOperandImmediateInt(op2) > 0))) {
+        linkSlowCase(iter);
+        linkSlowCase(iter);
+        // There is an extra slow case for (op1 * -N) or (-N * op2), to check for 0 since this should produce a result of -0.
+        JITStubCall stubCall(this, JITStubs::cti_op_mul);
+        stubCall.addArgument(op1, regT2);
+        stubCall.addArgument(op2, regT2);
+        stubCall.call(result);
+    } else
+        compileBinaryArithOpSlowCase(op_mul, iter, result, op1, op2, OperandTypes::fromInt(currentInstruction[4].u.operand));
+}
+
+void JIT::emit_op_sub(Instruction* currentInstruction)
+{
+    compileBinaryArithOp(op_sub, currentInstruction[1].u.operand, currentInstruction[2].u.operand, currentInstruction[3].u.operand, OperandTypes::fromInt(currentInstruction[4].u.operand));
+}
+
+void JIT::emitSlow_op_sub(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    compileBinaryArithOpSlowCase(op_sub, iter, currentInstruction[1].u.operand, currentInstruction[2].u.operand, currentInstruction[3].u.operand, OperandTypes::fromInt(currentInstruction[4].u.operand));
+}
+
+#endif // !ENABLE(JIT_OPTIMIZE_ARITHMETIC)
+
+/* ------------------------------ END: OP_ADD, OP_SUB, OP_MUL ------------------------------ */
 
 } // namespace JSC