<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 --- - GVN removes assumes if there are multiple assumes for the same predicate in a loop"
href="https://llvm.org/bugs/show_bug.cgi?id=25285">25285</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>GVN removes assumes if there are multiple assumes for the same predicate in a loop
</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>Windows NT
</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>Scalar Optimizations
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>michael.m.kuperstein@intel.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>Running GVN over the below test case results in both assumes being removed:
define i32 @foo (i32 %val, i1 %k) {
br label %next
next:
tail call void @llvm.assume(i1 %k)
tail call void @llvm.assume(i1 %k)
%ret = call i32 @do(i32 %val)
%cont = call i1 @continue(i32 %ret)
br i1 %cont, label %next, label %end
end:
ret i32 %ret
}
declare i1 @continue(i32) #0
declare i32 @do(i32) #0
declare void @llvm.assume(i1) #0
attributes #0 = { nounwind }
This does not happen if there is only one assume in the "next" block, or if the
block is not in a loop (e.g. the branch is an unconditional branch to "end")</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>