[clang] [llvm] [AMDGPU] Add amdgpu-as MMRA for fences (PR #78572)

[Sameer Sahasrabuddhe via cfe-commits]

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@@ -18365,6 +18366,28 @@ Value *CodeGenFunction::EmitHLSLBuiltinExpr(unsigned BuiltinID,
   return nullptr;
 }
 
+void CodeGenFunction::AddAMDGCNFenceAddressSpaceMMRA(llvm::Instruction *Inst,
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ssahasra wrote:

The function immediately below this uses "AMDGPU" in its name. I think that's the newer practice. I don't have a strong opinion on this, because the same file also has functions which say "AMDGCN" instead. I am not sure which way the naming convention is leaning.

https://github.com/llvm/llvm-project/pull/78572