[clang] [llvm] [clang][Driver] Add HIPAMD Driver support for AMDGCN flavoured SPIR-V (PR #95061)

[Yaxun Liu via cfe-commits]

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@@ -147,6 +147,14 @@ getNVIDIAOffloadTargetTriple(const Driver &D, const ArgList &Args,
 static std::optional<llvm::Triple>
 getHIPOffloadTargetTriple(const Driver &D, const ArgList &Args) {
   if (!Args.hasArg(options::OPT_offload_EQ)) {
+    auto OffloadArchs = Args.getAllArgValues(options::OPT_offload_arch_EQ);
+    if (llvm::find(OffloadArchs, "amdgcnspirv") != OffloadArchs.cend()) {
+      if (OffloadArchs.size() == 1)
+        return llvm::Triple("spirv64-amd-amdhsa");
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yxsamliu wrote:

Use a toolchain with spirv64 as triple will cause trouble for us to support mixed amdgcn and spirv fat binaries, which is critical for us.

Better to take the approach similar to https://github.com/llvm/llvm-project/pull/75357, i.e. treat spirv as a processor of amgcn triple, so that we can use HIPAMD toolchain for both spirv and real amdgcn processor.

https://github.com/llvm/llvm-project/pull/95061