diff --git a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Integer.cpp b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Integer.cpp
index a2041c35b5..a95ebd0289 100644
--- a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Integer.cpp
+++ b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Integer.cpp
@@ -294,36 +294,45 @@ void JitIL::mullwx(UGeckoInstruction inst)
 
 void JitIL::mulhwux(UGeckoInstruction inst)
 {
-	Default(inst); return;
-#if 0
-	if(Core::g_CoreStartupParameter.bJITOff || Core::g_CoreStartupParameter.bJITIntegerOff)
-		{Default(inst); return;} // turn off from debugger
+	INSTRUCTION_START
+	JITDISABLE(Integer)
 
-	INSTRUCTION_START;
-	int a = inst.RA, b = inst.RB, d = inst.RD;
-	gpr.FlushLockX(EDX);
-	gpr.Lock(a, b, d);
-	if (d != a && d != b) {
-		gpr.LoadToX64(d, false, true);
-	} else {
-		gpr.LoadToX64(d, true, true);
-	}
-	if (gpr.RX(d) == EDX)
-		PanicAlert("mulhwux : WTF");
-	MOV(32, R(EAX), gpr.R(a));
-	gpr.KillImmediate(b);
-	MUL(32, gpr.R(b));
-	gpr.UnlockAll();
-	gpr.UnlockAllX();
-	if (inst.Rc) {
-		MOV(32, R(EAX), R(EDX));
-		MOV(32, gpr.R(d), R(EDX));
-		// result is already in eax
-		CALL((u8*)asm_routines.computeRc);
-	} else {
-		MOV(32, gpr.R(d), R(EDX));
-	}
-#endif
+	// Compute upper 32-bit of (a * b) using Karatsuba algorithm
+	// Karatsuba algorithm reduces the number of multiplication 4 to 3
+	//   d = a * b
+	//     = {a1 * (1 << 16) + a0} * {b1 * (1 << 16) + b0};
+	//     = d2 * (1 << 32) + d1 * (1 << 16) + d0
+	// where
+	//   d2 = a1 * b1
+	//   d0 = a0 * b0
+	//   d1 = (a1 + a0) * (b1 * b0) - d2 - d0
+	// since
+	//   d1 = (a1 + a0) * (b1 * b0) - d2 - d0
+	//      = a1 * b1 + a1 * b0 + a0 * b1 + a0 * b0 - a1 * b1 - a0 * b0
+	//      = a1 * b0 + a0 * b1
+	// The result of mulhwux is
+	//   d2' = (((d0 >> 16) + d1) >> 16) + d2
+	//
+	// Though it is not so fast...
+	IREmitter::InstLoc a = ibuild.EmitLoadGReg(inst.RA);
+	IREmitter::InstLoc a0 = ibuild.EmitAnd(a, ibuild.EmitIntConst(0xFFFF));
+	IREmitter::InstLoc a1 = ibuild.EmitShrl(a, ibuild.EmitIntConst(16));
+	IREmitter::InstLoc b = ibuild.EmitLoadGReg(inst.RB);
+	IREmitter::InstLoc b0 = ibuild.EmitAnd(b, ibuild.EmitIntConst(0xFFFF));
+	IREmitter::InstLoc b1 = ibuild.EmitShrl(b, ibuild.EmitIntConst(16));
+
+	IREmitter::InstLoc d2 = ibuild.EmitMul(a1, b1);
+	IREmitter::InstLoc d0 = ibuild.EmitMul(a0, b0);
+	IREmitter::InstLoc d1 = ibuild.EmitMul(ibuild.EmitAdd(a1, a0), ibuild.EmitAdd(b1, b0));
+	d1 = ibuild.EmitSub(d1, d2);
+	d1 = ibuild.EmitSub(d1, d0);
+
+	d1 = ibuild.EmitAdd(d1, ibuild.EmitShrl(d0, ibuild.EmitIntConst(16)));
+	d2 = ibuild.EmitAdd(d2, ibuild.EmitShrl(d1, ibuild.EmitIntConst(16)));
+
+	ibuild.EmitStoreGReg(d2, inst.RD);
+	if (inst.Rc)
+		ComputeRC(ibuild, d2);
 }
 
 // skipped some of the special handling in here - if we get crashes, let the interpreter handle this op
@@ -375,36 +384,28 @@ void JitIL::addzex(UGeckoInstruction inst)
 	if (inst.Rc)
 		ComputeRC(ibuild, val);
 }
-// This can be optimized
+
 void JitIL::addex(UGeckoInstruction inst)
 {
-	Default(inst); return;
-#if 0
-	// USES_XER
-	if(Core::g_CoreStartupParameter.bJITOff || Core::g_CoreStartupParameter.bJITIntegerOff)
-		{Default(inst); return;} // turn off from debugger
+	INSTRUCTION_START
+	JITDISABLE(Integer)
 
-	INSTRUCTION_START;
-	int a = inst.RA, b = inst.RB, d = inst.RD;
-	gpr.FlushLockX(ECX);
-	gpr.Lock(a, b, d);
-	if (d != a && d != b)
-		gpr.LoadToX64(d, false);
-	else
-		gpr.LoadToX64(d, true);
-	MOV(32, R(EAX), M(&PowerPC::ppcState.spr[SPR_XER]));
-	SHR(32, R(EAX), Imm8(30)); // shift the carry flag out into the x86 carry flag
-	MOV(32, R(EAX), gpr.R(a));
-	ADC(32, R(EAX), gpr.R(b));
-	MOV(32, gpr.R(d), R(EAX));
-	//GenerateCarry(ECX);
-	gpr.UnlockAll();
-	gpr.UnlockAllX();
+	IREmitter::InstLoc a = ibuild.EmitLoadGReg(inst.RA);
+	IREmitter::InstLoc b = ibuild.EmitLoadGReg(inst.RB);
+
+	IREmitter::InstLoc ab = ibuild.EmitAdd(a, b);
+	IREmitter::InstLoc new_carry = ibuild.EmitICmpUlt(ab, a);
+
+	IREmitter::InstLoc previous_carry = ibuild.EmitLoadCarry();
+	IREmitter::InstLoc abc = ibuild.EmitAdd(ab, previous_carry);
+	new_carry = ibuild.EmitOr(new_carry, ibuild.EmitICmpUlt(abc, ab));
+
+	ibuild.EmitStoreGReg(abc, inst.RD);
+	ibuild.EmitStoreCarry(new_carry);
+
+	if (inst.OE) PanicAlert("OE: addex");
 	if (inst.Rc)
-	{
-		CALL((u8*)asm_routines.computeRc);
-	}
-#endif
+		ComputeRC(ibuild, abc);
 }
 
 void JitIL::rlwinmx(UGeckoInstruction inst)
diff --git a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_SystemRegisters.cpp b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_SystemRegisters.cpp
index 9356729d69..4e9f765773 100644
--- a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_SystemRegisters.cpp
+++ b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_SystemRegisters.cpp
@@ -128,63 +128,31 @@ void JitIL::mftb(UGeckoInstruction inst)
 
 void JitIL::mfcr(UGeckoInstruction inst)
 {
-	Default(inst); return;
-#if 0
-	if(Core::g_CoreStartupParameter.bJITOff || Core::g_CoreStartupParameter.bJITSystemRegistersOff)
-	{Default(inst); return;} // turn off from debugger
 	INSTRUCTION_START;
-	// USES_CR
-	int d = inst.RD;
-	gpr.LoadToX64(d, false, true);
-	MOV(8, R(EAX), M(&PowerPC::ppcState.cr_fast[0]));
-	SHL(32, R(EAX), Imm8(4));
-	for (int i = 1; i < 7; i++) {
-		OR(8, R(EAX), M(&PowerPC::ppcState.cr_fast[i]));
-		SHL(32, R(EAX), Imm8(4));
+	JITDISABLE(SystemRegisters)
+
+	IREmitter::InstLoc d = ibuild.EmitIntConst(0);
+	for (int i = 0; i < 8; ++i)
+	{
+		d = ibuild.EmitShl(d, ibuild.EmitIntConst(4));
+		d = ibuild.EmitOr(d, ibuild.EmitLoadCR(i));
 	}
-	OR(8, R(EAX), M(&PowerPC::ppcState.cr_fast[7]));
-	MOV(32, gpr.R(d), R(EAX));
-#endif
+	ibuild.EmitStoreGReg(d, inst.RD);
 }
 
 void JitIL::mtcrf(UGeckoInstruction inst)
 {
-	Default(inst); return;
-#if 0
-	if(Core::g_CoreStartupParameter.bJITOff || Core::g_CoreStartupParameter.bJITSystemRegistersOff)
-	{Default(inst); return;} // turn off from debugger
 	INSTRUCTION_START;
+	JITDISABLE(SystemRegisters)
 
-	// USES_CR
-	u32 mask = 0;
-	u32 crm = inst.CRM;
-	if (crm == 0xFF) {
-		gpr.FlushLockX(ECX);			
-		MOV(32, R(EAX), gpr.R(inst.RS));
-		for (int i = 0; i < 8; i++) {
-			MOV(32, R(ECX), R(EAX));
-			SHR(32, R(ECX), Imm8(28 - (i * 4)));
-			AND(32, R(ECX), Imm32(0xF));
-			MOV(8, M(&PowerPC::ppcState.cr_fast[i]), R(ECX));
+	IREmitter::InstLoc s = ibuild.EmitLoadGReg(inst.RS);
+	for (int i = 0; i < 8; ++i)
+	{
+		if (inst.CRM & (1 << i))
+		{
+			ibuild.EmitStoreCR(ibuild.EmitAnd(ibuild.EmitShrl(s, ibuild.EmitIntConst(28 - 4 * i)), ibuild.EmitIntConst(0xf)), i);
 		}
-		gpr.UnlockAllX();
-	} else {
-		Default(inst);
-		return;
-
-		// TODO: translate this to work in new CR model.
-		for (int i = 0; i < 8; i++) {
-			if (crm & (1 << i))
-				mask |= 0xF << (i*4);
-		}
-		MOV(32, R(EAX), gpr.R(inst.RS));
-		MOV(32, R(ECX), M(&PowerPC::ppcState.cr));
-		AND(32, R(EAX), Imm32(mask));
-		AND(32, R(ECX), Imm32(~mask));
-		OR(32, R(EAX), R(ECX));
-		MOV(32, M(&PowerPC::ppcState.cr), R(EAX));
 	}
-#endif
 }
 
 void JitIL::crXX(UGeckoInstruction inst)
diff --git a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Tables.cpp b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Tables.cpp
index 6830f9da1d..9024080402 100644
--- a/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Tables.cpp
+++ b/Source/Core/Core/Src/PowerPC/Jit64IL/JitIL_Tables.cpp
@@ -186,7 +186,7 @@ static GekkoOPTemplate table19[] =
 	{193, &JitIL::crXX}, //"crxor",  OPTYPE_CR, FL_EVIL}},
 												   
 	{150, &JitIL::DoNothing}, //"isync",  OPTYPE_ICACHE, FL_EVIL}},
-	{0,   &JitIL::Default}, //"mcrf",   OPTYPE_SYSTEM, FL_EVIL}},
+	{0,   &JitIL::mfcr}, //"mcrf",   OPTYPE_SYSTEM, FL_EVIL}},
 												   
 	{50,  &JitIL::rfi}, //"rfi",    OPTYPE_SYSTEM, FL_ENDBLOCK | FL_CHECKEXCEPTIONS, 1}},
 	{18,  &JitIL::Default}, //"rfid",   OPTYPE_SYSTEM, FL_ENDBLOCK | FL_CHECKEXCEPTIONS}}