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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Thin LTO ignores -fno-vectorize and -fno-slp-vectorize"
href="https://bugs.llvm.org/show_bug.cgi?id=45434">45434</a>
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<th>Summary</th>
<td>Thin LTO ignores -fno-vectorize and -fno-slp-vectorize
</td>
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<th>Product</th>
<td>lld
</td>
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<th>Version</th>
<td>unspecified
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>All Bugs
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
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<th>Reporter</th>
<td>dave@znu.io
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org, smithp352@googlemail.com
</td>
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<p>
<div>
<pre>Currently, there is no way to disable loop or SLP vectorization when using LTO.
This is unfortunate when targeting AVX2 or AVX512 machines where poor cost
modeling by the auto-vectorizers becomes painfully obvious.
The normal workaround doesn't work either, namely:
`-Wl,-plugin-opt,-vectorize-loops=false and
-Wl,-plugin-opt,-vectorize-slp=false`. Teresa Johnson confirmed via private
email that this is the case.</pre>
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