[llvm] [VectorCombine] Fix duplicate freeze scheduling for shared indexes (PR #213461)

[via llvm-commits]

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@@ -2140,9 +2141,11 @@ bool VectorCombine::scalarizeLoadExtract(LoadInst *LI, VectorType *VecTy,
     Value *Idx = EI->getIndexOperand();
 
     // Insert 'freeze' for poison indexes.
-    auto It = NeedFreeze.find(EI);
-    if (It != NeedFreeze.end())
+    auto It = NeedFreeze.find(cast<Instruction>(Idx));
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ParkHanbum wrote:

ExtractElementInst can have constant as operand.

https://github.com/llvm/llvm-project/pull/213461