[Mlir-commits] [mlir] [mlir][affine] fix the issue of ceildiv-mul-ceildiv form expression n… (PR #111254)

[Johannes Reifferscheid]

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@@ -406,12 +419,25 @@ static bool isDivisibleBySymbol(AffineExpr expr, unsigned symbolPos,
     AffineBinaryOpExpr binaryExpr = cast<AffineBinaryOpExpr>(expr);
     if (opKind != expr.getKind())
       return false;
-    return isDivisibleBySymbol(binaryExpr.getLHS(), symbolPos, expr.getKind());
+    if (llvm::any_of(visitedExprs, [](auto expr) {
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jreiffers wrote:

I don't understand this condition. I didn't understand the condition before either, but I still don't understand it. Won't this say `that s0 // 42 + s0` is divisible by `s0`? 

I think we should have unit tests for isDivisibleBySymbol, not just integration-style tests for all of simplification.

https://github.com/llvm/llvm-project/pull/111254