[llvm] [InstCombine] Propagate poison pow[i] (PR #146750)

[via llvm-commits]

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@@ -6793,6 +6793,9 @@ static Value *simplifyIntrinsic(CallBase *Call, Value *Callee,
   Function *F = cast<Function>(Callee);
   Intrinsic::ID IID = F->getIntrinsicID();
 
+  if (IID != Intrinsic::not_intrinsic && intrinsicPropagatesPoison(IID) &&
+      any_of(Args, IsaPred<PoisonValue>))
+    return PoisonValue::get(F->getReturnType());
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badumbatish wrote:

this generalizes the handling of poison propagation, but which intrinsics will be poison-propagated will be gated by intrinsicPropagatesPoison.

This is akin to how #146878 handles its poison propagation. Since we only add the case of pow[i] to the switch statement it shouldn't add support for others.

https://github.com/llvm/llvm-project/pull/146750