<html>
<head>
<base href="https://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 --- - CopyFromReg with a use removed with -jump-is-expensive=false"
href="https://llvm.org/bugs/show_bug.cgi?id=31914">31914</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>CopyFromReg with a use removed with -jump-is-expensive=false
</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>All
</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>Backend: PowerPC
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>nemanja.i.ibm@gmail.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=17956" name="attach_17956" title="Test case to reproduce the failure">attachment 17956</a> <a href="attachment.cgi?id=17956&action=edit" title="Test case to reproduce the failure">[details]</a></span>
Test case to reproduce the failure
Compiling the attached test case with -jump-is-expensive=false
-verify-machineinstrs illustrates the problem. Without -verify-machineinstrs,
it's a segfault in MachineCSE because the pass will get a definition of a vreg
from MachineRegisterInfo and dereference the returned null pointer.
This failure appears as of revision 292944 (<a href="https://reviews.llvm.org/rL292944">https://reviews.llvm.org/rL292944</a>).
To reproduce:
llc -verify-machineinstrs -jump-is-expensive=false
-mtriple=powerpc64le-unknown-unknown -mcpu=pwr8 crashWithCheapBranches.ll</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>