[AArch64] Implement frspx

Improves performance in povray bench by 2%

Source/Core/Core/PowerPC/JitArm64/Jit.h

@@ -145,6 +145,7 @@ public:
 	void fsubsx(UGeckoInstruction inst);
 	void fsubx(UGeckoInstruction inst);
 	void fcmpx(UGeckoInstruction inst);
+	void frspx(UGeckoInstruction inst);
 
 	// Paired
 	void ps_abs(UGeckoInstruction inst);

Source/Core/Core/PowerPC/JitArm64/JitArm64_FloatingPoint.cpp

@@ -458,6 +458,22 @@ void JitArm64::fsubx(UGeckoInstruction inst)
 	}
 }
 
+void JitArm64::frspx(UGeckoInstruction inst)
+{
+	INSTRUCTION_START
+	JITDISABLE(bJITFloatingPointOff);
+
+	u32 b = inst.FB, d = inst.FD;
+	fpr.BindToRegister(d, d == b, false);
+
+	ARM64Reg VB = fpr.R(b);
+	ARM64Reg VD = fpr.R(d, false);
+
+	m_float_emit.FCVTN(32, EncodeRegToDouble(VD), EncodeRegToDouble(VB));
+	m_float_emit.FCVTL(64, EncodeRegToDouble(VD), EncodeRegToDouble(VD));
+	m_float_emit.INS(64, VD, 1, VD, 0);
+}
+
 void JitArm64::fcmpx(UGeckoInstruction inst)
 {
 	INSTRUCTION_START

Source/Core/Core/PowerPC/JitArm64/JitArm64_Tables.cpp

@@ -334,7 +334,7 @@ static GekkoOPTemplate table63[] =
 	{72,  &JitArm64::fmrx},                     // fmrx
 	{136, &JitArm64::fnabsx},                   // fnabsx
 	{40,  &JitArm64::fnegx},                    // fnegx
-	{12,  &JitArm64::FallBackToInterpreter},    // frspx
+	{12,  &JitArm64::frspx},                    // frspx
 
 	{64,  &JitArm64::FallBackToInterpreter},    // mcrfs
 	{583, &JitArm64::FallBackToInterpreter},    // mffsx