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

[Shilei Tian via cfe-commits]

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@@ -626,6 +626,18 @@ static Value *emitQuaternaryBuiltin(CodeGenFunction &CGF, const CallExpr *E,
   return CGF.Builder.CreateCall(F, {Src0, Src1, Src2, Src3});
 }
 
+static Value *emitQuinaryBuiltin(CodeGenFunction &CGF, const CallExpr *E,
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shiltian wrote:

If we look at existing `emitXXXBuiltin` (ignore quaternary one which was added by me), it looks like `XXX` means the number of arguments we have for the builtin, and all of them just have single mangling.
I think a better unified function signature might be `template <unsigned N> void emitBuiltinWithSingleMangling` but it is out of the scope. I can do it in a separate patch.

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