[clang] [llvm] [AArch64] Add optional extensions enabled on Grace (PR #127620)

[David Green via cfe-commits]

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@@ -944,6 +944,15 @@ def ProcessorFeatures {
   list<SubtargetFeature> Falkor   = [HasV8_0aOps, FeatureCRC, FeatureSHA2, FeatureAES,
                                      FeatureFPARMv8, FeatureNEON, FeaturePerfMon,
                                      FeatureRDM];
+  list<SubtargetFeature> Grace    =  [HasV9_0aOps, FeatureBF16, FeatureSPE,
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davemgreen wrote:

Does it work to do something like `!listconcat(NeoverseV2, [<New features>])`?

It is probably better to use `FeatureSHA2, FeatureAES` than `FeatureCrypto` nowadays.

https://github.com/llvm/llvm-project/pull/127620