[llvm] [SCEV] Fold (C * A /u C) -> A, if A is a multiple of C and C a pow-of-2. (PR #156730)

[Philip Reames via llvm-commits]

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@@ -3215,6 +3215,15 @@ const SCEV *ScalarEvolution::getMulExpr(SmallVectorImpl<const SCEV *> &Ops,
           return getZeroExtendExpr(Res, Ops[1]->getType(), Depth + 1);
         };
       }
+
+      // Try to fold (C * D /u C) -> D, if C is a power-of-2 and D is a multiple
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preames wrote:

> Would you like me to include either generalization here or OK as followup?

Followups are totally fine.  

https://github.com/llvm/llvm-project/pull/156730