[llvm] Simplify `(a % b) lt/ge (b-1)` into `(a % b) eq/ne (b-1)` (PR #72504)

[Yingwei Zheng via llvm-commits]

================
@@ -6837,6 +6837,25 @@ Instruction *InstCombinerImpl::visitICmpInst(ICmpInst &I) {
     Changed = true;
   }
 
+  {
+    Value *X, *Y;
+    const APInt *C;
+    ICmpInst::Predicate Pred = I.getPredicate();
+    if ((Pred == ICmpInst::ICMP_SGE || Pred == ICmpInst::ICMP_SLT) &&
+        match(Op0, m_OneUse(m_SRem(m_Value(X), m_Value(Y)))) &&
+        ((match(Op1, m_OneUse(m_c_Add(m_Deferred(Y), m_AllOnes()))) &&
+          isKnownNonNegative(Y, DL, 0, Q.AC, Q.CxtI, Q.DT)) ||
----------------
dtcxzyw wrote:

Please rebase on https://github.com/llvm/llvm-project/commit/4b3ea337ad188d5c3ff05bf64cc61c3355e66376.

https://github.com/llvm/llvm-project/pull/72504