[clang] [Clang][AMDGPU] Add builtins for instrinsic `llvm.amdgcn.raw.buffer.store` (PR #94576)

[Shilei Tian via cfe-commits]

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@@ -149,6 +149,19 @@ BUILTIN(__builtin_amdgcn_mqsad_pk_u16_u8, "WUiWUiUiWUi", "nc")
 BUILTIN(__builtin_amdgcn_mqsad_u32_u8, "V4UiWUiUiV4Ui", "nc")
 
 BUILTIN(__builtin_amdgcn_make_buffer_rsrc, "Qbv*sii", "nc")
+BUILTIN(__builtin_amdgcn_raw_ptr_buffer_store_i8, "vcQbiiIi", "n")
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shiltian wrote:

The current variants don't have v16 version anyway. I think it might be more reasonable to provide the actual low level thingy to users and they need to take care of types, since we never know what kind of types there will be.

https://github.com/llvm/llvm-project/pull/94576