<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/86079>86079</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            missed fold, failed to kill redundant shufflevector
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            llvm:optimizations,
            llvm:instcombine
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          zhengyang92
      </td>
    </tr>
</table>

<pre>
    https://godbolt.org/z/T4sTh8W87
https://alive2.llvm.org/ce/z/fh2VmQ

```
define <2 x float> @src(<2 x float> %0, i8 %1) {
if.else433:
  %2 = shufflevector <2 x float> %0, <2 x float> poison, <2 x i32> <i32 1, i32 poison>
  %3 = fneg <2 x float> %0
  %4 = shufflevector <2 x float> %2, <2 x float> %3, <2 x i32> <i32 0, i32 3>
  ret <2 x float> %4
}

define <2 x float> @tgt(<2 x float> %0, i8 %1) {
if.else433:
  %2 = fneg <2 x float> %0
  %sv = shufflevector <2 x float> %0, <2 x float> %2, <2 x i32> <i32 1, i32 3>
  ret <2 x float> %sv
}
```
@dtcxzyw @regehr @RKSimon 
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJysVEFvnDwQ_TXDxcrKjM0CBw5JNly-09dG7dngAdwae4XNNtlfX0E2zWaTSJFaCYHxPM97fg-sQjC9I6ogu4Fsl6g5Dn6qjgO5_lG5vsSk8fqxGmLcBxDXgDVg3XvdeBs3fuoB6yNgfS_D_VB8L3LgO-DXr-HKmgPhxtrDeFrS0mldN-C38f-nRaf7lp-u9VVTZxwxELfIHlhnvYog7hhIHqYWsHhTwIwD3jJTLMMUsGSQ3zz1Mt2GbCApxCJtnWILChmIHQvD3HWWDtRGP70lPPW9nN97E7w7qxiBK17cGoEsXbUIfMaJuzNesfJ2jvr36V6Q8nMK8T2FC9GH-vizPnEmbaL4Xhd5Cijfnef1cUCxj_80oM8YFQ5_keWFgx8k-QmnwuHSqtcfNUiuY_twfPy1-DRRT8O0jL7899WM3rFEV0KXolQJVWme8rLMt1uZDBU2SK0UosW0aLK0yzDDNlNc56i4kG1iKuQoucCUyxRTsSk6yrXIqMianNJtA5LTqIz98zcmJoSZqmLL8zKxqiEb1sMAcUGAuPb7aEZzVNF4FwAXh16KxoXY-rExjpZStkumaildNXMfQHJrQgwvXNFES9VoQiDNOm_1YmqnjCXNomc_jbVsIj07rVx8nWIyT_byGDJxmJtN60fAehX09LjaT_4HtRGwXjcXAOt1f78DAAD__-nmYBY">