[llvm] [SCEV] Fix incorrect NUW inference (PR #70521)

[Nikita Popov via llvm-commits]

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@@ -12637,6 +12637,11 @@ ScalarEvolution::howManyLessThans(const SCEV *LHS, const SCEV *RHS,
       const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(ZExt->getOperand());
       if (AR && AR->getLoop() == L && AR->isAffine()) {
         auto canProveNUW = [&]() {
+          // We can use the comparison to infer no-wrap flags only it fully
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nikic wrote:

```suggestion
          // We can use the comparison to infer no-wrap flags only if it fully
```

https://github.com/llvm/llvm-project/pull/70521