[llvm] [InstSimplify] Fold `X * C >= X` to `true` (PR #129352)

[Nikita Popov via llvm-commits]

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@@ -3047,24 +3049,31 @@ static void getUnsignedMonotonicValues(SmallPtrSetImpl<Value *> &Res, Value *V,
   if (Type == MonotonicType::GreaterEq) {
     if (match(I, m_Or(m_Value(X), m_Value(Y))) ||
         match(I, m_Intrinsic<Intrinsic::uadd_sat>(m_Value(X), m_Value(Y)))) {
-      getUnsignedMonotonicValues(Res, X, Type, Depth);
-      getUnsignedMonotonicValues(Res, Y, Type, Depth);
+      getUnsignedMonotonicValues(Res, X, Type, Q, Depth);
+      getUnsignedMonotonicValues(Res, Y, Type, Q, Depth);
+    }
+    // X * Y >= X --> true
+    if (match(I, m_NUWMul(m_Value(X), m_Value(Y)))) {
+      if (isKnownNonZero(X, Q))
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nikic wrote:

Do we need the non-constant support?

https://github.com/llvm/llvm-project/pull/129352