AMDGPU/SI: Fix spilling of 96-bit registers

[• tstellarAMD]

Summary

It seems like this was broken in r252327. I thought we had test cases
for this, but it's really hard to tirgger spills of this exact register
size since they aren't used very much.

[arsenm]

LGTM

[nhaehnle]

LGTM

lib/Target/AMDGPU/SIInstrInfo.cpp

 }
 
 static unsigned getVGPRSpillSaveOpcode(unsigned Size) {
   switch (Size) {
   case 4:
     return AMDGPU::SI_SPILL_V32_SAVE;
   case 8:
     return AMDGPU::SI_SPILL_V64_SAVE;
+  case 12:
+    return AMDGPU::SI_SPILL_V96_SAVE;
   case 16:
     return AMDGPU::SI_SPILL_V128_SAVE;
   case 32:
     return AMDGPU::SI_SPILL_V256_SAVE;
   case 64:
     return AMDGPU::SI_SPILL_V512_SAVE;
   default:
     llvm_unreachable("unknown register size");

 }
 
 static unsigned getVGPRSpillRestoreOpcode(unsigned Size) {
   switch (Size) {
   case 4:
     return AMDGPU::SI_SPILL_V32_RESTORE;
   case 8:
     return AMDGPU::SI_SPILL_V64_RESTORE;
+  case 12:
+    return AMDGPU::SI_SPILL_V96_RESTORE;
   case 16:
     return AMDGPU::SI_SPILL_V128_RESTORE;
   case 32:
     return AMDGPU::SI_SPILL_V256_RESTORE;
   case 64:
     return AMDGPU::SI_SPILL_V512_RESTORE;
   default:
     llvm_unreachable("unknown register size");