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

[Paul Walker via llvm-commits]

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@@ -1477,6 +1480,37 @@ void VFABI::getVectorVariantNames(
   }
 }
 
+std::optional<FunctionType *>
+VFABI::createFunctionType(const VFInfo &Info, const FunctionType *ScalarFTy) {
+  ElementCount VF = Info.Shape.VF;
+  // Create vector parameter types
+  SmallVector<Type *, 8> VecTypes;
+  for (auto [STy, VFParam] : zip(ScalarFTy->params(), Info.Shape.Parameters)) {
+    if (VFParam.ParamKind == VFParamKind::Vector)
+      VecTypes.push_back(VectorType::get(STy, VF));
+    else
+      VecTypes.push_back(STy);
+  }
+
+  // Get mask's position mask and append one if not present in the Instruction.
+  int MaskPos = -1;
+  if (Info.isMasked()) {
+    auto OptMaskPos = Info.getParamIndexForOptionalMask();
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paulwalker-arm wrote:

What about `if (auto OptMaskPos = Info.getParamIndexForOptionalMask())`?

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