[thirdparty/glibc.git] / sysdeps / i386 / fpu / s_fminl.S

/* Compute minimum of two numbers, regarding NaN as missing argument.
   Copyright (C) 1997-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <libm-alias-ldouble.h>
#include <sysdep.h>

	.text
ENTRY(__fminl)
	fldt	16(%esp)	// y
	fxam
	fnstsw
	fldt	4(%esp)		// y : x

	andb	$0x45, %ah
	cmpb	$0x01, %ah
	je	2f		// y == NaN

	fxam
	fnstsw
	andb	$0x45, %ah
	cmpb	$0x01, %ah
	je	3f		// x == NaN

	fucom	%st(1)
	fnstsw
	sahf
	jc	1f

	fxch	%st(1)
1:	fstp	%st(1)

	ret

2:	// st(1) is a NaN; st(0) may or may not be.
	fxam
	fnstsw
	andb	$0x45, %ah
	cmpb	$0x01, %ah
	je	4f
	// st(1) is a NaN; st(0) is not.  Test if st(1) is signaling.
	testb	$0x40, 23(%esp)
	jz	4f
	fstp	%st(1)
	ret

3:	// st(0) is a NaN; st(1) is not.  Test if st(0) is signaling.
	testb	$0x40, 11(%esp)
	jz	4f
	fstp	%st(0)
	ret

4:	// Both arguments are NaNs, or one is a signaling NaN.
	faddp
	ret
END(__fminl)
libm_alias_ldouble (__fmin, fmin)
Commit	Line	Data
6973fc01	1	/* Compute minimum of two numbers, regarding NaN as missing argument.
2b778ceb	2	Copyright (C) 1997-2021 Free Software Foundation, Inc.
6973fc01 UD	3	This file is part of the GNU C Library.
	4	Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
	5
	6	The GNU C Library is free software; you can redistribute it and/or
41bdb6e2 AJ	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.
6973fc01 UD	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
41bdb6e2	14	Lesser General Public License for more details.
6973fc01	15
41bdb6e2	16	You should have received a copy of the GNU Lesser General Public
59ba27a6	17	License along with the GNU C Library; if not, see
5a82c748	18	<https://www.gnu.org/licenses/>. */
6973fc01	19
2ce30701	20	#include <libm-alias-ldouble.h>
6973fc01 UD	21	#include <sysdep.h>
	22
	23	.text
	24	ENTRY(__fminl)
0a2546cd JM	25	fldt 16(%esp) // y
	26	fxam
	27	fnstsw
	28	fldt 4(%esp) // y : x
	29
	30	andb $0x45, %ah
	31	cmpb $0x01, %ah
	32	je 2f // y == NaN
6973fc01 UD	33
	34	fxam
	35	fnstsw
	36	andb $0x45, %ah
	37	cmpb $0x01, %ah
0a2546cd	38	je 3f // x == NaN
6973fc01 UD	39
	40	fucom %st(1)
	41	fnstsw
	42	sahf
0a2546cd JM	43	jc 1f
	44
	45	fxch %st(1)
	46	1: fstp %st(1)
	47
	48	ret
6973fc01	49
0a2546cd JM	50	2: // st(1) is a NaN; st(0) may or may not be.
	51	fxam
	52	fnstsw
	53	andb $0x45, %ah
	54	cmpb $0x01, %ah
	55	je 4f
	56	// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
	57	testb $0x40, 23(%esp)
	58	jz 4f
	59	fstp %st(1)
	60	ret
	61
	62	3: // st(0) is a NaN; st(1) is not. Test if st(0) is signaling.
	63	testb $0x40, 11(%esp)
	64	jz 4f
	65	fstp %st(0)
	66	ret
6973fc01	67
0a2546cd JM	68	4: // Both arguments are NaNs, or one is a signaling NaN.
0a2546cd JM	69	faddp
6973fc01 UD	70	ret
6973fc01 UD	71	END(__fminl)
2ce30701	72	libm_alias_ldouble (__fmin, fmin)