AMDGPU: Stop reporting is-noop addrspacecast for constant 32-bit

This will require something to cast. Before this would eliminate
the cast, which would result in copies of $noreg.

llvm-svn: 341803
diff --git a/llvm/lib/Target/AMDGPU/SIISelLowering.cpp b/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
index 9359d53..520ed141 100644
--- a/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
@@ -1120,8 +1120,7 @@
 static bool isFlatGlobalAddrSpace(unsigned AS) {
   return AS == AMDGPUAS::GLOBAL_ADDRESS ||
          AS == AMDGPUAS::FLAT_ADDRESS ||
-         AS == AMDGPUAS::CONSTANT_ADDRESS ||
-         AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT;
+         AS == AMDGPUAS::CONSTANT_ADDRESS;
 }
 
 bool SITargetLowering::isNoopAddrSpaceCast(unsigned SrcAS,