1/* Compute maximum of two numbers, regarding NaN as missing argument.
2   Copyright (C) 2002-2022 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <sysdep.h>
20#include <libm-alias-double.h>
21
22	.text
23ENTRY(__fmax)
24	ucomisd	%xmm0, %xmm1
25	jp	1f		// jump if unordered
26	maxsd	%xmm1, %xmm0
27	jmp	2f
28
291:	ucomisd	%xmm1, %xmm1	// Is xmm1 a NaN?
30	jp	3f
31	// xmm0 is a NaN; xmm1 is not.  Test if xmm0 is signaling.
32	movsd	%xmm0, -8(%rsp)
33	testb	$0x8, -2(%rsp)
34	jz	4f
35	movsd	%xmm1, %xmm0	// otherwise return xmm1
36	ret
37
383:	// xmm1 is a NaN; xmm0 may or may not be.
39	ucomisd	%xmm0, %xmm0
40	jp	4f
41	// xmm1 is a NaN; xmm0 is not.  Test if xmm1 is signaling.
42	movsd	%xmm1, -8(%rsp)
43	testb	$0x8, -2(%rsp)
44	jz	4f
45	ret
46
474:	// Both arguments are NaNs, or one is a signaling NaN.
48	addsd	%xmm1, %xmm0
49
502:	ret
51END(__fmax)
52libm_alias_double (__fmax, fmax)
53