[llvm] [VFABI] Create FunctionType for vector functions (PR #75058)

[Paschalis Mpeis via llvm-commits]

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@@ -1477,6 +1479,34 @@ void VFABI::getVectorVariantNames(
   }
 }
 
+std::optional<std::pair<FunctionType *, int>>
+VFABI::createFunctionType(const VFInfo &Info, const FunctionType *ScalarFTy,
+                          Type *VecRetTy, const Module *M) {
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paschalis-mpeis wrote:

Discussed in person and decided to drop `VecRetTy`.

`VFInfo` does not hold such information since mangled names do not encode it,
however, if that changes then it will. So one should be able to get it from there.

https://github.com/llvm/llvm-project/pull/75058