[AMDPU] Add support for idxen and bothen buffer load/store merging in SILoadStoreOptimizer (#86285)

Added more buffer instruction merging support

Author: dstutt

llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp

@@ -399,19 +399,35 @@ static InstClassEnum getInstClass(unsigned Opc, const SIInstrInfo &TII) {
       switch (AMDGPU::getMUBUFBaseOpcode(Opc)) {
       default:
         return UNKNOWN;
+      case AMDGPU::BUFFER_LOAD_DWORD_BOTHEN:
+      case AMDGPU::BUFFER_LOAD_DWORD_BOTHEN_exact:
+      case AMDGPU::BUFFER_LOAD_DWORD_IDXEN:
+      case AMDGPU::BUFFER_LOAD_DWORD_IDXEN_exact:
       case AMDGPU::BUFFER_LOAD_DWORD_OFFEN:
       case AMDGPU::BUFFER_LOAD_DWORD_OFFEN_exact:
       case AMDGPU::BUFFER_LOAD_DWORD_OFFSET:
       case AMDGPU::BUFFER_LOAD_DWORD_OFFSET_exact:
+      case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_BOTHEN:
+      case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_BOTHEN_exact:
+      case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_IDXEN:
+      case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_IDXEN_exact:
       case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_OFFEN:
       case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_OFFEN_exact:
       case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_OFFSET:
       case AMDGPU::BUFFER_LOAD_DWORD_VBUFFER_OFFSET_exact:
         return BUFFER_LOAD;
+      case AMDGPU::BUFFER_STORE_DWORD_BOTHEN:
+      case AMDGPU::BUFFER_STORE_DWORD_BOTHEN_exact:
+      case AMDGPU::BUFFER_STORE_DWORD_IDXEN:
+      case AMDGPU::BUFFER_STORE_DWORD_IDXEN_exact:
       case AMDGPU::BUFFER_STORE_DWORD_OFFEN:
       case AMDGPU::BUFFER_STORE_DWORD_OFFEN_exact:
       case AMDGPU::BUFFER_STORE_DWORD_OFFSET:
       case AMDGPU::BUFFER_STORE_DWORD_OFFSET_exact:
+      case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_BOTHEN:
+      case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_BOTHEN_exact:
+      case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_IDXEN:
+      case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_IDXEN_exact:
       case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_OFFEN:
       case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_OFFEN_exact:
       case AMDGPU::BUFFER_STORE_DWORD_VBUFFER_OFFSET: