<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/92561>92561</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            SIFixSGPRCopies inserts waterfall loop with undefined implicit use of scc
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:AMDGPU
      </td>
    </tr>

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

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

<pre>
    With this [test case](https://github.com/llvm/llvm-project/files/15351548/reduced.txt) I get:
```
$ ~/llvm-release/bin/llc -mtriple=amdgcn -mcpu=gfx1100 -o /dev/null -verify-machineinstrs reduced.txt
[...]
*** Bad machine code: Using an undefined physical register ***
- function:    main
- basic block: %bb.0 bb (0x895f278)
- instruction: %65:sreg_32 = S_CSELECT_B32 1, 0, implicit $scc
- operand 3:   implicit $scc
LLVM ERROR: Found 1 machine code errors.
[...]
```
</pre>
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