[PATCH] D105392: [InstCombine] Add optimization to prevent poison from being propagated.

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:3544
+    SmallPtrSet<const Value *, 4> NonPoisonOps;
+    getGuaranteedNonPoisonOps(Inst, NonPoisonOps);
+    if (Inst->hasOneUse() && !canCreateUndefOrPoison(dyn_cast<Operator>(Op0)) &&
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This is the wrong API to use here: You want `isGuaranteedNotToBeUndefOrPoison()` on the operands of the instruction.

`getGuaranteedNonPoisonOps()` is about which operands of an instruction would result in immediate UB if they are poison.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105392/new/

https://reviews.llvm.org/D105392