[PATCH] D96929: [ValueTracking] Improve impliesPoison

[Juneyoung Lee via Phabricator via llvm-commits]

aqjune marked an inline comment as done.
aqjune added inline comments.


================
Comment at: llvm/lib/Analysis/ValueTracking.cpp:4888-4890
+    if (isa<ExtractValueInst>(I) && isa<ExtractValueInst>(ValAssumedPoison)) {
+      if (I->getOperand(0) == I2->getOperand(0) &&
+          isAllPoisonOrNot(I->getOperand(0)))
----------------
spatel wrote:
> Are there other patterns that you are planning to add here?
> If not, we could make the patch much smaller with a more direct match like we use in InstCombineSelect.cpp:
>   WithOverflowInst *II;
>   if (!match(CondVal, m_ExtractValue<1>(m_WithOverflowInst(II))) ||
>       !match(FalseVal, m_ExtractValue<0>(m_Specific(II))))
>     return nullptr;
Yep, I think dealing with overflow instructions is enough.
I updated the code to use matches (with updates in PatternMatch.h)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D96929/new/

https://reviews.llvm.org/D96929