[llvm] [DA] Fix the check between Subscript and Size after delinearization (PR #151326)

[Ryotaro Kasuga via llvm-commits]

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@@ -719,12 +719,14 @@ for.end:                                          ; preds = %for.body
 ;;    for(int j = 0; j < M; j+=1)
 ;;      A[M*N + M*i + j] = 2;
 
+; FIXME: Currently failing to infer %M being positive.
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kasuga-fj wrote:

I might be misunderstanding something, but in principle, we can infer it from `nsw` on `%add10.us`?

https://github.com/llvm/llvm-project/pull/151326