[llvm] [LowerBufferFatPointers] Fix support for GEP T, p7, <N x T> idxs (PR #126126)

[Matt Arsenault via llvm-commits]

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@@ -1804,14 +1804,26 @@ PtrParts SplitPtrStructs::visitGetElementPtrInst(GetElementPtrInst &GEP) {
   bool IsNUW = GEP.hasNoUnsignedWrap();
   bool IsNUSW = GEP.hasNoUnsignedSignedWrap();
 
+  Type *ResTy = GEP.getType();
+  std::optional<ElementCount> ResEC;
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arsenm wrote:

I don't see the point of ResEC, can just use the `dyn_cast<VectorType>` result later?

https://github.com/llvm/llvm-project/pull/126126