<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54870>54870</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            codegen backend optimization pass not printed with -debug-pass=Arguments in LTO
        </td>
    </tr>

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

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

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

<pre>
    For example, using `-Oz` optimization level, using `-mllvm -debug-pass=Arguments`  to see whether Machine Outliner pass is executed.

When using -fno-lto, all passes are printed, included:
```
 -machine-outliner
```

But when using -flto, all codegen backend releated pass not printed.

Is this behaviour intended or a bug? 

And is there a way to print codegen backend pass in LTO mode?

Thanks.
</pre>
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