[clang] [llvm] [AArch64][FMV] Add missing feature dependencies and detect at runtime. (PR #119231)

[Alexandros Lamprineas via llvm-commits]

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@@ -349,6 +349,14 @@ void AArch64::ExtensionSet::reconstructFromParsedFeatures(
   }
 }
 
+uint64_t AArch64::ExtensionSet::toCpuSupportsMask() const {
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labrinea wrote:

Hmm, I am thinking we may want to reuse this once we change [getFMVPriority](https://github.com/llvm/llvm-project/pull/119231/files#diff-d380d584ecd28d0608428cfaf49b7d7a8df5ec765f7d8e94ab95f65bf7534cfcR51) (it is under discussion). Perhaps we want a better naming, like `toFMVFeatureMask`? I used the naming convetion inspired from `toLLVMFeatureList` in the same class.

https://github.com/llvm/llvm-project/pull/119231