[AMDGPU] Add FixupVectorISel pass, currently Supports SREGs in GLOBAL LD/ST

Add a pass to fixup various vector ISel issues.
Currently we handle converting GLOBAL_{LOAD|STORE}_*
and GLOBAL_Atomic_* instructions into their _SADDR variants.
This involves feeding the sreg into the saddr field of the new instruction.

llvm-svn: 347008
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
index fc1e712..c43389a 100644
--- a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -755,6 +755,7 @@
   case AMDGPU::VS_64RegClassID:
   case AMDGPU::SReg_64RegClassID:
   case AMDGPU::VReg_64RegClassID:
+  case AMDGPU::SReg_64_XEXECRegClassID:
     return 64;
   case AMDGPU::VReg_96RegClassID:
     return 96;