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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Redundant vmov{q,d} before 32-bit splat"
href="https://bugs.llvm.org/show_bug.cgi?id=45314">45314</a>
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<th>Summary</th>
<td>Redundant vmov{q,d} before 32-bit splat
</td>
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<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
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<th>OS</th>
<td>Windows NT
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>Backend: X86
</td>
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
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<th>Reporter</th>
<td>daan@dsprenkels.com
</td>
</tr>
<tr>
<th>CC</th>
<td>craig.topper@gmail.com, llvm-bugs@lists.llvm.org, llvm-dev@redking.me.uk, spatel+llvm@rotateright.com
</td>
</tr></table>
<p>
<div>
<pre>The following code:
```
#include <immintrin.h>
__m256i broadcast(const __m256i x) {
return _mm256_set_epi32(x[0], x[0], x[0], x[0], x[0], x[0], x[0], x[0]);
}
```
is compiled to:
```
broadcast: # @broadcast
vmovq rax, xmm0
vmovd xmm0, eax
vpbroadcastd ymm0, xmm0
ret
```
These two vmov operations are redundant.
GCC already omits these operations:
```
broadcast:
vpbroadcastd ymm0, xmm0
ret
```
Godbolt link: <a href="https://c.godbolt.org/z/bkVDWj">https://c.godbolt.org/z/bkVDWj</a></pre>
</div>
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