<html>
<head>
<base href="https://bugs.llvm.org/">
</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 - Bug in APFloat::mod"
href="https://bugs.llvm.org/show_bug.cgi?id=32177">32177</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Bug in APFloat::mod
</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>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Core LLVM classes
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>sanjoy@playingwithpointers.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>Running @test_a through -instcombine folds %val to 0.0, while at runtime
executing @test_b returns a non-zero value 185438208.000000. I suspect this is
a bug in APFloat::mod (though I do not speak floating point well enough to be
sure):
define float @test_a() {
entry:
%val = frem float 0x43cbfcd960000000, 0xc1e2b34a00000000
ret float %val
}
define float @helper(float %x, float %y) {
%val = frem float %x, %y
ret float %val
}
define external float @test_b() {
%val = call float @helper(float 0x43cbfcd960000000, float 0xc1e2b34a00000000)
ret float %val
}
Notably, IEEEFloat::mod says: "This is not currently correct in all cases".</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>