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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Failure to vectorize a std::find across a dereferencable array"
href="https://bugs.llvm.org/show_bug.cgi?id=46518">46518</a>
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<th>Summary</th>
<td>Failure to vectorize a std::find across a dereferencable array
</td>
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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
</td>
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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>Scalar Optimizations
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>llvm-dev@redking.me.uk
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<th>CC</th>
<td>florian_hahn@apple.com, lebedev.ri@gmail.com, llvm-bugs@lists.llvm.org, spatel+llvm@rotateright.com
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<p>
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<pre>#include <array>
#include <algorithm>
bool findme(const std::array<int, 8> &db, int key) {
return std::find(db.begin(), db.end(), key) != db.end();
}
<a href="https://godbolt.org/z/rdWStD">https://godbolt.org/z/rdWStD</a>
We end up with a full cmp+branch tree when we could very efficiently use a
vector comparison followed by an anyof reduction.</pre>
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