added an assert for scratch flat

Author: broxigarchen

llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp

@@ -2395,6 +2395,7 @@ bool SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
 
       unsigned Opc;
       if (MI->getOpcode() == AMDGPU::SI_SPILL_V16_SAVE) {
+        assert(ST.enableFlatScratch() && "Flat Scratch is not enabled!");
         Opc = AMDGPU::SCRATCH_STORE_SHORT_SADDR_t16;
       } else {
         Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_STORE_DWORD_SADDR
@@ -2470,6 +2471,7 @@ bool SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
 
       unsigned Opc;
       if (MI->getOpcode() == AMDGPU::SI_SPILL_V16_RESTORE) {
+        assert(ST.enableFlatScratch() && "Flat Scratch is not enabled!");
         Opc = AMDGPU::SCRATCH_LOAD_SHORT_D16_SADDR_t16;
       } else {
         Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_LOAD_DWORD_SADDR