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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - And in cmp expanded too much"
href="https://bugs.llvm.org/show_bug.cgi?id=41340">41340</a>
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<th>Summary</th>
<td>And in cmp expanded too much
</td>
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<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
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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>Linux
</td>
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<th>Status</th>
<td>NEW
</td>
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<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
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>david.bolvansky@gmail.com
</td>
</tr>
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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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<p>
<div>
<pre>int and_cmp(int x) {
return (x & 2048) == 0;
}
Clang trunk:
and_cmp(int): # @and_cmp(int)
mov eax, edi
shr eax, 11
not eax
and eax, 1
ret
Expected:
and_cmp(int):
xor eax, eax
and edi, 2048
sete al
ret
The problem is the return type. If I change it to bool, I get:
and_cmp(unsigned int): # @and_cmp(unsigned int)
test edi, 2048
sete al
ret
Clang should realize in the int case, that the range of the return value is i1
only.
All -OX levels affected.</pre>
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