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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [InstSimplify] Miscompilation of sdiv + urem"
href="https://bugs.llvm.org/show_bug.cgi?id=32948">32948</a>
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<th>Summary</th>
<td>[InstSimplify] Miscompilation of sdiv + urem
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<th>Product</th>
<td>libraries
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<th>Version</th>
<td>trunk
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<th>Hardware</th>
<td>All
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
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<th>Keywords</th>
<td>miscompilation
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<th>Severity</th>
<td>normal
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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>nunoplopes@sapo.pt
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<th>CC</th>
<td>david.majnemer@gmail.com, llvm-bugs@lists.llvm.org, regehr@cs.utah.edu, spatel+llvm@rotateright.com
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<pre>InstSimplify miscompiles the following:
define i2 @func76883517(i2) {
%2 = sdiv exact i2 1, %0
%3 = sdiv exact i2 -1, %0
%4 = urem i2 %2, %3
ret i2 %4
}
$ opt -S a.ll -instsimplify
define i2 @func76883517(i2) {
%2 = sdiv exact i2 1, %0
ret i2 %2
}
Alive says:
%0 i2 = 0x3 (3, -1)
%2 i2 = 0x3 (3, -1)
%3 i2 = 0x1 (1)
%4 i2 = 0x0 (0)
%5 i2 = 0x3 (3, -1)
Source value: 0x0 (0)
Target value: 0x3 (3, -1)
<a href="http://rise4fun.com/Alive/wslA">http://rise4fun.com/Alive/wslA</a></pre>
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