[clang] [SPIR-V] Add hlsl_private address space for HLSL/SPIR-V (PR #122103)

[Nathan Gauër via cfe-commits]

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@@ -83,6 +84,7 @@ const LangASMap AMDGPUTargetInfo::AMDGPUDefIsPrivMap = {
     llvm::AMDGPUAS::FLAT_ADDRESS, // ptr32_uptr
     llvm::AMDGPUAS::FLAT_ADDRESS, // ptr64
     llvm::AMDGPUAS::FLAT_ADDRESS, // hlsl_groupshared
+    llvm::AMDGPUAS::FLAT_ADDRESS, // hlsl_private
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Keenuts wrote:

This address space will be used for:
 - static [const] global variables
Which matches the `Private` storage class for SPIR-V.

Would `LOCAL_ADDRESS` be a better match?

https://github.com/llvm/llvm-project/pull/122103