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

[Tom Honermann 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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tahonermann wrote:

I'm not fond of singling out AMD as a vendor here. Microsoft is embracing SPIR-V these days, so a future `spirv64-microsoft-XXX` could be a reality.

Ideally, I think we would require the vendor component to be `intel`. If that isn't an option, then I think we should not bother with attempting to diagnose the AMD case.

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