[clang] [llvm] [NFC][clang][FMV][TargetInfo] Refactor API for FMV feature priority. (PR #116257)

[Alexandros Lamprineas via cfe-commits]

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@@ -218,8 +218,8 @@ void ABIInfo::appendAttributeMangling(StringRef AttrStr,
     // only have "+" prefixes here.
     assert(LHS.starts_with("+") && RHS.starts_with("+") &&
            "Features should always have a prefix.");
-    return TI.multiVersionSortPriority(LHS.substr(1)) >
-           TI.multiVersionSortPriority(RHS.substr(1));
+    return TI.getFMVPriority({LHS.substr(1)}) >
+           TI.getFMVPriority({RHS.substr(1)});
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labrinea wrote:

Perhaps there is value in adding another hook `getFMVPriority(StringRef feature)` which would be called on each feature of `ArrayRef<StringRef> Features` from the other hook, in order to avoid this inefficiency here of having to create a single element smallvector each time?

https://github.com/llvm/llvm-project/pull/116257