<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/150229>150229</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [GVN] hits assertion "Cannot split critical edge from IndirectBrInst" in llvm::SplitKnownCriticalEdge
        </td>
    </tr>

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

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

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

<pre>
    The gvn pass cannot handle the indirectbr instruction with more than one destination. It hits an assertion in llvm::SplitKnownCriticalEdge trying to add a "dead" block after the indirectbr.
The newgvn pass works fine.

Reproducer:
```llvm
define void @foo(i1 %cmp) {
first:
  br i1 %cmp, label %exit, label %second

second:
  br i1 %cmp, label %ibr, label %exit ; cmp must be false to reach this, branch to ibr never taken

ibr: ; this block is dead
 indirectbr ptr blockaddress(@foo, %exit), [label %exit, label %exit] ; double label required, works with just one

exit:
  ret void
}
```

`opt --passes=gvn -S minimal.ll`

Related Bug: https://github.com/llvm/llvm-project/issues/49237
</pre>
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