+// Try and copy between VR128/VR64 and GR64 registers.
+static unsigned CopyToFromAsymmetricReg(unsigned DestReg, unsigned SrcReg) {
+ // SrcReg(VR128) -> DestReg(GR64)
+ // SrcReg(VR64) -> DestReg(GR64)
+ // SrcReg(GR64) -> DestReg(VR128)
+ // SrcReg(GR64) -> DestReg(VR64)
+
+ if (X86::GR64RegClass.contains(DestReg)) {
+ if (X86::VR128RegClass.contains(SrcReg)) {
+ // Copy from a VR128 register to a GR64 register.
+ return X86::MOVPQIto64rr;
+ } else if (X86::VR64RegClass.contains(SrcReg)) {
+ // Copy from a VR64 register to a GR64 register.
+ return X86::MOVSDto64rr;
+ }
+ } else if (X86::GR64RegClass.contains(SrcReg)) {
+ // Copy from a GR64 register to a VR128 register.
+ if (X86::VR128RegClass.contains(DestReg))
+ return X86::MOV64toPQIrr;
+ // Copy from a GR64 register to a VR64 register.
+ else if (X86::VR64RegClass.contains(DestReg))
+ return X86::MOV64toSDrr;
+ }
+
+ return 0;
+}
+