1/* Compute maximum of two numbers, regarding NaN as missing argument.
2 Copyright (C) 2002-2018 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Andreas Jaeger <aj@suse.de>, 2002.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20#include <sysdep.h>
21#include <libm-alias-double.h>
22
23 .text
24ENTRY(__fmax)
25 ucomisd %xmm0, %xmm1
26 jp 1f // jump if unordered
27 maxsd %xmm1, %xmm0
28 jmp 2f
29
301: ucomisd %xmm1, %xmm1 // Is xmm1 a NaN?
31 jp 3f
32 // xmm0 is a NaN; xmm1 is not. Test if xmm0 is signaling.
33 movsd %xmm0, -8(%rsp)
34 testb $0x8, -2(%rsp)
35 jz 4f
36 movsd %xmm1, %xmm0 // otherwise return xmm1
37 ret
38
393: // xmm1 is a NaN; xmm0 may or may not be.
40 ucomisd %xmm0, %xmm0
41 jp 4f
42 // xmm1 is a NaN; xmm0 is not. Test if xmm1 is signaling.
43 movsd %xmm1, -8(%rsp)
44 testb $0x8, -2(%rsp)
45 jz 4f
46 ret
47
484: // Both arguments are NaNs, or one is a signaling NaN.
49 addsd %xmm1, %xmm0
50
512: ret
52END(__fmax)
53libm_alias_double (__fmax, fmax)
54