xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/arm/copyd.asm (revision 41f3ac3e09f0c1c4d8b911b4c8a1d6450bd14f46)
1dnl  ARM mpn_copyd.
2
3dnl  Contributed to the GNU project by Robert Harley and Torbjörn Granlund.
4
5dnl  Copyright 2003, 2012, 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	 1.25-1.5
41C Cortex-A15	 1.25
42
43C TODO
44C  * Consider wider unrolling.  Analogous 8-way code runs 10% faster on both A9
45C    and A15.  But it probably slows things down for 8 <= n < a few dozen.
46
47define(`rp', `r0')
48define(`up', `r1')
49define(`n',  `r2')
50
51ASM_START()
52PROLOGUE(mpn_copyd)
53	mov	r12, n, lsl #2
54	sub	r12, r12, #4
55	add	rp, rp, r12
56	add	up, up, r12
57
58	tst	n, #1
59	beq	L(skip1)
60	ldr	r3, [up], #-4
61	str	r3, [rp], #-4
62L(skip1):
63	tst	n, #2
64	beq	L(skip2)
65	ldmda	up!, { r3,r12 }
66	stmda	rp!, { r3,r12 }
67L(skip2):
68	bics	n, n, #3
69	beq	L(rtn)
70
71	push	{ r4-r5 }
72	subs	n, n, #4
73	ldmda	up!, { r3,r4,r5,r12 }
74	beq	L(end)
75
76L(top):	subs	n, n, #4
77	stmda	rp!, { r3,r4,r5,r12 }
78	ldmda	up!, { r3,r4,r5,r12 }
79	bne	L(top)
80
81L(end):	stmda	rp, { r3,r4,r5,r12 }
82	pop	{ r4-r5 }
83L(rtn):	return	lr
84EPILOGUE()
85