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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Suboptimal lowering of conditional binop identity"
href="https://bugs.llvm.org/show_bug.cgi?id=47922">47922</a>
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<th>Summary</th>
<td>Suboptimal lowering of conditional binop identity
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<th>Product</th>
<td>libraries
</td>
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<th>Version</th>
<td>trunk
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<th>Hardware</th>
<td>PC
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<th>OS</th>
<td>All
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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>laytonkifer@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, pengfei.wang@intel.com, spatel+llvm@rotateright.com
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<pre>The x86 backend fails to notice when expanding selects/phis will cause things
like addition of 0 and emits unnecessary instructions.
examples: <a href="https://godbolt.org/z/j5onGK">https://godbolt.org/z/j5onGK</a>
I would potentially be interested in looking into this, but I am fairly new to
LLVM. This would be my first time working on one of the backends. If anyone
could point me in the right direction as to where to begin, that would be
great.</pre>
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