[clang] [llvm] [clang][SPIR-V] Add support for AMDGCN flavoured SPIRV (PR #89796)

[Joseph Huber via cfe-commits]

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@@ -6088,6 +6088,9 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
   StringRef Prefix =
       llvm::Triple::getArchTypePrefix(getTarget().getTriple().getArch());
   if (!Prefix.empty()) {
+    if (Prefix == "spv" &&
+        getTarget().getTriple().getOS() == llvm::Triple::OSType::AMDHSA)
+      Prefix = "amdgcn";
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jhuber6 wrote:

So I was just wondering if it would make more sense to put this in `Triple::getArchTypePrefix(ArchType Kind)` because I wasn't sure if this logic is the expected return value there.

https://github.com/llvm/llvm-project/pull/89796