[llvm] VT: teach isImpliedCondMatchingOperands about samesign (PR #122474)

[Yingwei Zheng via llvm-commits]

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@@ -9374,12 +9374,11 @@ isImpliedCondOperands(CmpInst::Predicate Pred, const Value *ALHS,
 /// Return true if "icmp1 LPred X, Y" implies "icmp2 RPred X, Y" is true.
 /// Return false if "icmp1 LPred X, Y" implies "icmp2 RPred X, Y" is false.
 /// Otherwise, return std::nullopt if we can't infer anything.
-static std::optional<bool>
-isImpliedCondMatchingOperands(CmpInst::Predicate LPred,
-                              CmpInst::Predicate RPred) {
-  if (CmpInst::isImpliedTrueByMatchingCmp(LPred, RPred))
+static std::optional<bool> isImpliedCondMatchingOperands(CmpPredicate LPred,
+                                                         CmpPredicate RPred) {
+  if (ICmpInst::isImpliedTrueByMatchingCmp(LPred, RPred))
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dtcxzyw wrote:

Seems like `isImpliedTrueByMatchingCmp` and `isImpliedFalseByMatchingCmp` are always called together. We can replace them with a helper `std::optional<bool> isImpliedByMatchingCmp` in the future.


https://github.com/llvm/llvm-project/pull/122474