<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 - Missed optimization in math expression: max(min(a,b),max(a,b)) == max(a,b)"
href="https://bugs.llvm.org/show_bug.cgi?id=35607">35607</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Missed optimization in math expression: max(min(a,b),max(a,b)) == max(a,b)
</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>Common Code Generator Code
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>zamazan4ik@tut.by
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>clang(trunk) with '--std=c++17 -O3 -march=native -ffast-math' flags for this
code:
#include <algorithm>
int test(int a, int b)
{
return std::max(std::min(a,b), std::max(a,b));
}
generates this assembly:
test(int, int): # @test(int, int)
cmp esi, edi
mov eax, edi
cmovle eax, esi
cmp edi, esi
cmovl edi, esi
cmp eax, edi
cmovge edi, eax
mov eax, edi
ret
gcc(trunk) with '--std=c++17 -O3 -march=native -ffast-math':
test(int, int):
cmp edi, esi
mov eax, edi
cmovl eax, esi
ret
Helpful link:
<a href="https://github.com/gcc-mirror/gcc/blob/07b69d3f1cd3dd8ebb0af1fbff95914daee477d2/gcc/match.pd">https://github.com/gcc-mirror/gcc/blob/07b69d3f1cd3dd8ebb0af1fbff95914daee477d2/gcc/match.pd</a></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>