[llvm] [VFABI] Refactor try demangle for vfabi to use only the vector abi mangled names (PR #67430)

[Paul Walker via llvm-commits]

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@@ -174,13 +174,9 @@ static constexpr char const *_LLVM_Scalarize_ = "_LLVM_Scalarize_";
 ///
 /// \param MangledName -> input string in the format
 /// _ZGV<isa><mask><vlen><parameters>_<scalarname>[(<redirection>)].
-/// \param M -> Module used to retrieve informations about the vector
-/// function that are not possible to retrieve from the mangled
-/// name. At the moment, this parameter is needed only to retrieve the
-/// Vectorization Factor of scalable vector functions from their
-/// respective IR declarations.
+/// \param CI -> the call instruction.
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paulwalker-arm wrote:

It's worth being a little more verbose here and say something like "the call instruction to the scalar function to which MangledName is being linked and whose return and parameter types are required to calculate the expected ElementCount for the matching vector function".

https://github.com/llvm/llvm-project/pull/67430