xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/x86/atom/cnd_sub_n.asm (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1dnl  X86 mpn_cnd_sub_n optimised for Intel Atom.
2
3dnl  Copyright 2013 Free Software Foundation, Inc.
4
5dnl  This file is part of the GNU MP Library.
6dnl
7dnl  The GNU MP Library is free software; you can redistribute it and/or modify
8dnl  it under the terms of either:
9dnl
10dnl    * the GNU Lesser General Public License as published by the Free
11dnl      Software Foundation; either version 3 of the License, or (at your
12dnl      option) any later version.
13dnl
14dnl  or
15dnl
16dnl    * the GNU General Public License as published by the Free Software
17dnl      Foundation; either version 2 of the License, or (at your option) any
18dnl      later version.
19dnl
20dnl  or both in parallel, as here.
21dnl
22dnl  The GNU MP Library is distributed in the hope that it will be useful, but
23dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
24dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
25dnl  for more details.
26dnl
27dnl  You should have received copies of the GNU General Public License and the
28dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
29dnl  see https://www.gnu.org/licenses/.
30
31include(`../config.m4')
32
33C			    cycles/limb
34C P5				 ?
35C P6 model 0-8,10-12		 ?
36C P6 model 9   (Banias)		 ?
37C P6 model 13  (Dothan)		 ?
38C P4 model 0-1 (Willamette)	 ?
39C P4 model 2   (Northwood)	 ?
40C P4 model 3-4 (Prescott)	 ?
41C Intel atom			 5.67
42C AMD K6			 ?
43C AMD K7			 ?
44C AMD K8			 ?
45
46
47define(`rp',  `%edi')
48define(`up',  `%esi')
49define(`vp',  `%ebp')
50define(`n',   `%ecx')
51define(`cnd', `20(%esp)')
52
53ASM_START()
54	TEXT
55	ALIGN(16)
56PROLOGUE(mpn_cnd_sub_n)
57	push	%edi
58	push	%esi
59	push	%ebx
60	push	%ebp
61
62	mov	cnd, %eax		C make cnd into a mask (1)
63	mov	24(%esp), rp
64	neg	%eax			C make cnd into a mask (1)
65	mov	28(%esp), up
66	sbb	%eax, %eax		C make cnd into a mask (1)
67	mov	32(%esp), vp
68	mov	%eax, cnd		C make cnd into a mask (1)
69	mov	36(%esp), n
70
71	xor	%edx, %edx
72
73	inc	n
74	shr	n
75	jnc	L(ent)
76
77	mov	0(vp), %eax
78	and	cnd, %eax
79	lea	4(vp), vp
80	mov	0(up), %edx
81	sub	%eax, %edx
82	lea	4(rp), rp
83	lea	4(up), up
84	mov	%edx, -4(rp)
85	sbb	%edx, %edx		C save cy
86
87L(ent):	mov	0(vp), %ebx
88	and	cnd, %ebx
89	add	%edx, %edx		C restore cy
90	mov	0(up), %edx
91	dec	n
92	je	L(end)
93
94L(top):	sbb	%ebx, %edx
95	mov	4(vp), %eax
96	mov	%edx, 0(rp)
97	sbb	%edx, %edx		C save cy
98	mov	8(vp), %ebx
99	lea	8(up), up
100	and	cnd, %ebx
101	and	cnd, %eax
102	add	%edx, %edx		C restore cy
103	mov	-4(up), %edx
104	lea	8(rp), rp
105	sbb	%eax, %edx
106	mov	%edx, -4(rp)
107	dec	n
108	mov	0(up), %edx
109	lea	8(vp), vp
110	jne	L(top)
111
112L(end):	sbb	%ebx, %edx
113	mov	%edx, 0(rp)
114
115	mov	$0, %eax
116	adc	%eax, %eax
117
118	pop	%ebp
119	pop	%ebx
120	pop	%esi
121	pop	%edi
122	ret
123EPILOGUE()
124ASM_END()
125