[clang] [llvm] [InstCombine] Fold `X > C2 ? X + C1 : C2 + C1` to `max(X, C2) + C1` (PR #116888)

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veera-sivarajan wrote:

> The more idiomatic way to handle this is to have something like if (match(FalseVal, m_Constant())) { std::swap(TrueVal, FalseVal); Pred = ICmpInst::getInversePredicate(Pred); } and then you no longer have to deal with which operand the constant is in.

Thank you for the detailed feedback.

This simplifies the pattern match but I still have to conditionally assign `NewTrue` and `NewFalse` because `matchDecomposedSelectPattern()` takes an `ICmpInst` and not a `ICmpInst:Predicate`.


https://github.com/llvm/llvm-project/pull/116888