<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/145875>145875</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [SCEV] Repeated max not hoisted out of loop
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            llvm:optimizations,
            llvm:SCEV,
            missed-optimization
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          aengelke
      </td>
    </tr>
</table>

<pre>
    The repeated computation of a maximum/minimum is not hoisted outside of a loop, preventing the elimination of the loop (instead, the loop gets pointlessly vectorized).

Example (https://godbolt.org/z/faM4od4dM; see also: https://alive2.llvm.org/ce/z/YqPC82)
```c++
#include <cstdint>
uint8_t f(uint8_t n, uint8_t a, uint8_t b) {
    for (uint8_t i = 0; i < n; i++)
 a = a < b ? b : a;
    return a;
}
```

To me this looks like something that SCEV should recognize (I might be wrong here, but in the end, the loop should get eliminated).
</pre>
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