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

[Sander de Smalen 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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sdesmalen-arm wrote:

I guess you could always move the functionality back into a separate function if future changes require that. That said, I would prefer `getFMVFeatureMask` if you keep it, because it makes it clear that the bitmask describes features for the purpose of FMV.

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