<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/142347>142347</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            slp-vectorizer miscompile
        </td>
    </tr>

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

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

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

<pre>
    llvm commit: 9801fdf669b
Reproduce with: ```opt -passes="slp-vectorizer" bbi-107513.ll -S -o -```
Result:
```
define i16 @foo() {
entry:
  %cond3 = select i1 false, i16 1, i16 0
  ret i16 %cond3
}
```
The function should return the value 1, but with slp-vectorizer we get 0 instead.

This starts happening with d41e517748e
```
[SLP] Make getSameOpcode support interchangeable instructions. (#135797)

We use the term "interchangeable instructions" to refer to different
operators that have the same meaning (e.g., `add x, 0` is equivalent to
`mul x, 1`).
Non-constant values are not supported, as they may incur high costs with
little benefit.

---------

Co-authored-by: Alexey Bataev <a.bataev@gmx.com>
```

[bbi-107513.ll.gz](https://github.com/user-attachments/files/20547856/bbi-107513.ll.gz)
</pre>
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