[llvm] [DependenceAnalysis] Fix incorrect analysis of wrapping AddRec expressions (PR #154982)

[Ryotaro Kasuga via llvm-commits]

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@@ -168,7 +168,7 @@ test2.for.body:                                         ; preds = %entry, %test2
   %add = fadd float %0, %1
   %arrayidx2 = getelementptr inbounds float, ptr %a, i64 %i.02
   store float %add, ptr %arrayidx2, align 4
-  %inc = add i64 %i.02, 1
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kasuga-fj wrote:

Why is it correct to add `nsw`? The pseudo code in the above says `%n` is unsigned.
As for the other tests, I generally think it's not a good idea to modify the IR.

https://github.com/llvm/llvm-project/pull/154982