[clang] [llvm] [TargetParser][clang] Parse and store Intel IGCA virtual architecture as an OffloadArch (PR #227468)

[Srividya Sundaram via cfe-commits]

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@@ -3928,6 +3928,11 @@ static StringRef getCanonicalArchString(Compilation &C,
         return StringRef();
       }
     }
+  } else if (Triple.isSPIRV() && ArchStr.starts_with("igca_") &&
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srividya-sundaram wrote:


> As for amdgcnspirv, what if I stop this check from running for all AMD triples?

 Could we instead reject IGCA names when `Triple.getVendor() == llvm::Triple::AMD`, and add the `spirv64-amd-amdhsa` test Tom asked for? 

https://github.com/llvm/llvm-project/pull/227468