[clang] [llvm] [ASan] Skip explicit check of 'xnack' feature for gfx1250 && gfx1251. (PR #166754)

[Joseph Huber via cfe-commits]

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@@ -161,6 +161,9 @@ enum ArchFeatureKind : uint32_t {
 
   // WGP mode is supported.
   FEATURE_WGP = 1 << 9,
+
+  // Xnack is available by default
+  FEATURE_XNACK_ALWAYS = 1 << 10
----------------
jhuber6 wrote:

The target ID handling always seemed weird. There's tons of history passing things like `-maxv2` and we could've just done `-Xarch_gfx942 -mxnack` or something. ELF flags are sufficient for binary loading, so I think the only relevance is for unpacking fat binaries which could've been more easily solved as a separate flag IMO. But I think ti's a little too late to reevaluate this.

https://github.com/llvm/llvm-project/pull/166754