[llvm] [ValueTracking] Compute knownbits from `(icmp ult/ule (add nuw X, Y), C)` (PR #87180)

[Yingwei Zheng via llvm-commits]

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@@ -9283,11 +9289,21 @@ void llvm::findValuesAffectedByCondition(
             AddAffected(X);
         }
       } else {
-        // Handle (A + C1) u< C2, which is the canonical form of
-        // A > C3 && A < C4.
-        if (match(A, m_AddLike(m_Value(X), m_ConstantInt())) &&
-            match(B, m_ConstantInt()))
-          AddAffected(X);
+        if (match(B, m_ConstantInt())) {
+          // Handle (A + C1) u< C2, which is the canonical form of
+          // A > C3 && A < C4.
+          if (match(A, m_AddLike(m_Value(X), m_ConstantInt())))
+            AddAffected(X);
+
+          Value *Y;
+          // X & Y u> C -> X >u C && Y >u C
+          // X | Y u< C -> X u< C && Y u< C
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dtcxzyw wrote:

Please update the comments.

https://github.com/llvm/llvm-project/pull/87180