[llvm] [StructurizeCFG] bug fix in zero cost hoist (PR #157969)

[Jay Foad via llvm-commits]

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@@ -435,24 +448,14 @@ static bool isHoistableInstruction(Instruction *I, BasicBlock *BB,
   // Check if any operands are instructions defined in the same block.
   for (auto &Op : I->operands()) {
     if (auto *OpI = dyn_cast<Instruction>(Op)) {
-      if (OpI->getParent() == BB)
+      if (OpI->getParent() == BB || !DT->dominates(OpI->getParent(), HoistTo))
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jayfoad wrote:

Do you still need the `== BB` check? Shouldn't it be subsumed by the `dominates` check?

https://github.com/llvm/llvm-project/pull/157969