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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [X86] Use scheduler models to remove inputs from dependency breaking instructions"
href="https://bugs.llvm.org/show_bug.cgi?id=39980">39980</a>
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<th>Summary</th>
<td>[X86] Use scheduler models to remove inputs from dependency breaking instructions
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<th>Product</th>
<td>libraries
</td>
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Windows NT
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>Backend: X86
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>craig.topper@gmail.com
</td>
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<th>CC</th>
<td>craig.topper@gmail.com, llvm-bugs@lists.llvm.org, llvm-dev@redking.me.uk, spatel+llvm@rotateright.com
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<pre>After r348959, the X86 backend creates more SBB instructions with a dependency
breaking MOV32r0 pseudo in front of it. On some AMD CPUs, SBB with the same
register is recognized as a dependency breaking instruction on its own. We
should remove the MOV32r0 dependency for those CPUs.</pre>
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