<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/112890>112890</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            On 32-bit x86, `half` return ABI is incorrect when SSE is enabled but SSE2 is disabled
        </td>
    </tr>

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

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

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

<pre>
    Consider the following IR ([compiler explorer](https://godbolt.org/z/nMrcsed1a)):

```llvm
target triple = "i586-unknown-linux-gnu"

define half @only_sse(half) #0 {
 ret half %0
}

attributes #0 = { "target-features"="+sse,-sse2" }

define half @sse_and_sse2(half) #1 {
    ret half %0
}

attributes #1 = { "target-features"="+sse,+sse2" }
```

The 32-bit x86 ABI for returning `half` is specified as using the `xmm0` register. As both `only_sse` and `sse_and_sse2` have SSE registers available, they should both be able to use the specified ABI. However, LLVM currently only compiles `sse_and_sse2` correctly, with `only_sse` incorrectly returning the `half` in `eax` instead.
</pre>
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