[llvm] LICM: teach hoistMinMax about samesign (PR #122730)

[Nikita Popov via llvm-commits]

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@@ -2453,16 +2453,16 @@ static bool hoistMinMax(Instruction &I, Loop &L, ICFLoopSafetyInfo &SafetyInfo,
   if (!MatchICmpAgainstInvariant(Cond1, P1, LHS1, RHS1) ||
       !MatchICmpAgainstInvariant(Cond2, P2, LHS2, RHS2))
     return false;
-  // FIXME: Use CmpPredicate::getMatching here.
-  if (P1 != static_cast<CmpInst::Predicate>(P2) || LHS1 != LHS2)
+  auto MatchingPred = CmpPredicate::getMatching(P1, P2);
+  if (!MatchingPred || LHS1 != LHS2)
     return false;
 
   // Everything is fine, we can do the transform.
   bool UseMin = ICmpInst::isLT(P1) || ICmpInst::isLE(P1);
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nikic wrote:

Also use MatchingPred here? Strictly speaking doesn't matter as these checks are signedness independent, but better safe than sorry.

https://github.com/llvm/llvm-project/pull/122730