[llvm] Fix mechanism propagating mangled names for TLI function mappings (PR #66656)

[Paul Walker via llvm-commits]

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@@ -171,11 +200,17 @@ class TargetLibraryInfoImpl {
   /// vectorization factor.
   bool isFunctionVectorizable(StringRef F) const;
 
-  /// Return the name of the equivalent of F, vectorized with factor VF. If no
-  /// such mapping exists, return the empty string.
+  /// Return the name of the equivalent of F, vectorized with factor VF.
+  /// If no such mapping exists, return empty strings.
   StringRef getVectorizedFunction(StringRef F, const ElementCount &VF,
                                   bool Masked) const;
 
+  /// Return a pointer to a VecDesc object holding all info for scalar to vector
+  /// mappings in TLI for the equivalent of F, vectorized with factor VF.
+  /// If no such mapping exists, return nullpointer.
+  const VecDesc *getMangledTLIVectorName(StringRef F, const ElementCount &VF,
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paulwalker-arm wrote:

Something like `getVectorMappingInfo` seems more representative of what the functions does?

https://github.com/llvm/llvm-project/pull/66656