[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 don't think that solves a real problem. I'm not particularly worried about users accidentally passing `--offload-arch=igcaXXX` for an AMD target.

We should have a definitive way of identifying targets that are appropriate for IGCA. If we don't (and the only reason we don't is because we have so far refused to make use of the vendor and OS components to identify Intel devices for reasons that remain unclear to me), then I think we're better off not trying to filter targets that are definitively not Intel rather than hoping that we managed to identify them all.

I think the right answer here would be to require the vendor component to be "intel" when using `--offload-arch=igcaXXX`. That will require further discussion though.

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