<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54650>54650</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [AArch64] Optimise modulo comparison operation
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    When the result of a modulo by constant is compared against another constant we can sometimes avoid the expensive modulo instructions as described in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87290

For example

```
int
mod16 (int a, int b)
{
  return a % 16 == 13;
}
```
with -O2 using this on aarch64 GCC produces better code: https://godbolt.org/z/9K8Gd1Eaf
</pre>
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