PatternMatch: migrate to CmpPredicate (#118534)

With the introduction of CmpPredicate in 51a895a (IR: introduce struct
with CmpInst::Predicate and samesign), PatternMatch is one of the first
key pieces of infrastructure that must be updated to match a CmpInst
respecting samesign information. Implement this change to Cmp-matchers.

This is a preparatory step in migrating the codebase over to
CmpPredicate. Since we no functional changes are desired at this stage,
we have chosen not to migrate CmpPredicate::operator==(CmpPredicate)
calls to use CmpPredicate::getMatching(), as that would have visible
impact on tests that are not yet written: instead, we call
CmpPredicate::operator==(Predicate), preserving the old behavior, while
also inserting a few FIXME comments for follow-ups.

1 files changed, 3 insertions, 5 deletions

diff --git a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
index 7fca1a6..f05d32d 100644
--- a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -2164,16 +2164,14 @@ void WidenIV::calculatePostIncRange(Instruction *NarrowDef,
       !NarrowDefRHS->isNonNegative())
     return;
 
-  auto UpdateRangeFromCondition = [&] (Value *Condition,
-                                       bool TrueDest) {
-    CmpInst::Predicate Pred;
+  auto UpdateRangeFromCondition = [&](Value *Condition, bool TrueDest) {
+    CmpPredicate Pred;
     Value *CmpRHS;
     if (!match(Condition, m_ICmp(Pred, m_Specific(NarrowDefLHS),
                                  m_Value(CmpRHS))))
       return;
 
-    CmpInst::Predicate P =
-            TrueDest ? Pred : CmpInst::getInversePredicate(Pred);
+    CmpPredicate P = TrueDest ? Pred : ICmpInst::getInverseCmpPredicate(Pred);
 
     auto CmpRHSRange = SE->getSignedRange(SE->getSCEV(CmpRHS));
     auto CmpConstrainedLHSRange =