<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72293>72293</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Missed optimization for unnecessary shl/ashr pair in loop body
        </td>
    </tr>

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

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

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

<pre>
    Similar to #72212.
Alive2 proof: https://alive2.llvm.org/ce/z/ifqwPe
Missed example: https://godbolt.org/z/W6YT9EPMz

Real-world motivation: This snippet of IR is derived from FFmpeg/.../extr_aacdec_template.c_decode_drc_channel_exclusions.c.

Let me know if you can confirm that it's an optimization opportunity, please.
</pre>
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