xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/arm/sec_tabselect.asm (revision 72c7faa4dbb41dbb0238d6b4a109da0d4b236dd4)
1dnl  ARM mpn_sec_tabselect
2
3dnl  Contributed to the GNU project by Torbjörn Granlund.
4
5dnl  Copyright 2013 Free Software Foundation, Inc.
6
7dnl  This file is part of the GNU MP Library.
8dnl
9dnl  The GNU MP Library is free software; you can redistribute it and/or modify
10dnl  it under the terms of either:
11dnl
12dnl    * the GNU Lesser General Public License as published by the Free
13dnl      Software Foundation; either version 3 of the License, or (at your
14dnl      option) any later version.
15dnl
16dnl  or
17dnl
18dnl    * the GNU General Public License as published by the Free Software
19dnl      Foundation; either version 2 of the License, or (at your option) any
20dnl      later version.
21dnl
22dnl  or both in parallel, as here.
23dnl
24dnl  The GNU MP Library is distributed in the hope that it will be useful, but
25dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
26dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
27dnl  for more details.
28dnl
29dnl  You should have received copies of the GNU General Public License and the
30dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
31dnl  see https://www.gnu.org/licenses/.
32
33include(`../config.m4')
34
35C	     cycles/limb
36C StrongARM	 ?
37C XScale	 ?
38C Cortex-A7	 ?
39C Cortex-A8	 ?
40C Cortex-A9	 2.33
41C Cortex-A15	 2.2
42
43C TODO
44C  * Consider using special code for small nents, either swapping the inner and
45C    outer loops, or providing a few completely unrolling the inner loops.
46
47define(`rp',    `r0')
48define(`tp',    `r1')
49define(`n',     `r2')
50define(`nents', `r3')
51C      which  on stack
52
53define(`i',     `r11')
54define(`j',     `r12')
55define(`c',     `r14')
56define(`mask',  `r7')
57
58ASM_START()
59PROLOGUE(mpn_sec_tabselect)
60	push	{r4-r11, r14}
61
62	subs	j, n, #3
63	bmi	L(outer_end)
64L(outer_top):
65	ldr	c, [sp, #36]
66	mov	i, nents
67	push	{tp}
68
69	mov	r8, #0
70	mov	r9, #0
71	mov	r10, #0
72
73L(top):	subs	c, c, #1
74	ldm	tp, {r4,r5,r6}
75	sbc	mask, mask, mask
76	subs	i, i, #1
77	add	tp, tp, n, lsl #2
78	and	r4, r4, mask
79	and	r5, r5, mask
80	and	r6, r6, mask
81	orr	r8, r8, r4
82	orr	r9, r9, r5
83	orr	r10, r10, r6
84	bge	L(top)
85
86	stmia	rp!, {r8,r9,r10}
87	pop	{tp}
88	add	tp, tp, #12
89	subs	j, j, #3
90	bpl	L(outer_top)
91L(outer_end):
92
93	cmp	j, #-1
94	bne	L(n2)
95
96	ldr	c, [sp, #36]
97	mov	i, nents
98	mov	r8, #0
99	mov	r9, #0
100L(tp2):	subs	c, c, #1
101	sbc	mask, mask, mask
102	ldm	tp, {r4,r5}
103	subs	i, i, #1
104	add	tp, tp, n, lsl #2
105	and	r4, r4, mask
106	and	r5, r5, mask
107	orr	r8, r8, r4
108	orr	r9, r9, r5
109	bge	L(tp2)
110	stmia	rp, {r8,r9}
111	pop	{r4-r11, r14}
112	return	lr
113
114L(n2):	cmp	j, #-2
115	bne	L(n1)
116
117	ldr	c, [sp, #36]
118	mov	i, nents
119	mov	r8, #0
120L(tp1):	subs	c, c, #1
121	sbc	mask, mask, mask
122	ldr	r4, [tp]
123	subs	i, i, #1
124	add	tp, tp, n, lsl #2
125	and	r4, r4, mask
126	orr	r8, r8, r4
127	bge	L(tp1)
128	str	r8, [rp]
129L(n1):	pop	{r4-r11, r14}
130	return	lr
131EPILOGUE()
132