<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/57770>57770</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            AArch32 vbfdotq_f32 causes internal compiler fault
        </td>
    </tr>

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

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

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

<pre>
    A function containing BF16 dot product causes a compiler fault.  Intrinsic looks like this
```vacc0x0 = vbfdotq_f32(vacc0x0, va0, vb0);```

Godbolt function that fails in clang15
https://godbolt.org/z/rxxcPjP9q

>From a command line built the error reported is:
```
fatal error: error in backend: Cannot select: 0x5555564090b8: v4bf16 = ARMISD::VEXT 0x55555640d1c0, 0x55555640d1c0, Constant:i32<2>
  0x55555640d1c0: v4bf16,ch = CopyFromReg 0x5555560e6648, Register:v4bf16 %114
    0x55555640d020: v4bf16 = Register %114
  0x55555640d1c0: v4bf16,ch = CopyFromReg 0x5555560e6648, Register:v4bf16 %114
    0x55555640d020: v4bf16 = Register %114
  0x555556418c40: i32 = Constant<2>
In function: xnn_bf16_gemm_minmax_ukernel_3x4c8__neonbf16_bfdot
```
</pre>
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