<html>
<head>
<base href="http://llvm.org/bugs/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - loop vectorizer miscompile (t10135 case from PR16431)"
href="http://llvm.org/bugs/show_bug.cgi?id=16455">16455</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>loop vectorizer miscompile (t10135 case from PR16431)
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Loop Optimizer
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>hfinkel@anl.gov
</td>
</tr>
<tr>
<th>CC</th>
<td>llvmbugs@cs.uiuc.edu
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=10767" name="attach_10767" title="bugpoint reduced test case and input file">attachment 10767</a> <a href="attachment.cgi?id=10767&action=edit" title="bugpoint reduced test case and input file">[details]</a></span>
bugpoint reduced test case and input file
The loop vectorizer miscompiles the attached input (there is an input text file
read by the program which demonstrates the problem). This is the t10135 case
from PR16431.
Specifically, if you run:
opt -loop-vectorize -mcpu=x86-64 bugpoint-passinput.ll
Then the resulting program outputs:
res = 3453
whereas compiling it without running the loop vectorizer, the resulting program
outputs:
res = 5321
Unfortunately, bugpoint crashes when attempting to further reduce the test case
:(
-- but at least it was able to isolate the relevant pass.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>