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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Incorrect code when right shifting signed int by more than its size"
href="https://bugs.llvm.org/show_bug.cgi?id=39914">39914</a>
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<th>Summary</th>
<td>Incorrect code when right shifting signed int by more than its size
</td>
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>7.0
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
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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
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<th>Component</th>
<td>-New Bugs
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>bugzilla@poradnik-webmastera.com
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<th>CC</th>
<td>htmldeveloper@gmail.com, llvm-bugs@lists.llvm.org, neeilans@live.com, richard-llvm@metafoo.co.uk
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<p>
<div>
<pre>When signed int is shifted right by more than its width, results will be either
0 or -1. However clang always evaluates this as 0. Sample code below, compiled
with "-O3 -march=skylake-avx512".
[code]
void f();
void g();
void test(int n)
{
if (n >> 222)
f();
else
g();
}
[/code]
[asm]
test(int): # @test(int)
jmp g() # TAILCALL
[/asm]</pre>
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