[llvm] [VectorCombine] scalarizeLoadExtract - don't create scalar loads if any extract is waiting to be erased (PR #129375)

[Simon Pilgrim via llvm-commits]

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@@ -1579,6 +1579,11 @@ bool VectorCombine::scalarizeLoadExtract(Instruction &I) {
     if (!UI || UI->getParent() != LI->getParent())
       return false;
 
+    // If any extract is waiting to be erased, then bail out as this will
+    // distort the cost calculation and possibly lead to infinite loops.
+    if (isInstructionTriviallyDead(UI))
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RKSimon wrote:

yes - as we're just dealing with extractelement instructions

https://github.com/llvm/llvm-project/pull/129375