[llvm] [AggressiveInstCombine] Fix crash when folding consecutive loads into a type smaller than the combined load (PR #207229)

[Kyungtak Woo via llvm-commits]

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@@ -1231,7 +1231,7 @@ struct LoadOps {
   bool FoundRoot = false;
   uint64_t LoadSize = 0;
   uint64_t Shift = 0;
-  Type *ZextType;
+  Type *ZextType = nullptr;
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kevinwkt wrote:

My bad.

https://github.com/llvm/llvm-project/pull/207229