[llvm] [SCEV] Improve handling of divisibility information from loop guards. (PR #163021)

[Florian Hahn via llvm-commits]

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@@ -15932,7 +15945,12 @@ void ScalarEvolution::LoopGuards::collectFromBlock(
             EnterIfTrue ? Cmp->getPredicate() : Cmp->getInversePredicate();
         const auto *LHS = SE.getSCEV(Cmp->getOperand(0));
         const auto *RHS = SE.getSCEV(Cmp->getOperand(1));
-        CollectCondition(Predicate, LHS, RHS, Guards.RewriteMap);
+        // If LHS is a constant, apply information to the other expression.
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fhahn wrote:

Yep, that currently just preserves the current behavior. I added a TODO

https://github.com/llvm/llvm-project/pull/163021