1/* memcpy.S
2 * Copyright (C) 2003-2007 Analog Devices Inc., All Rights Reserved.
3 *
4 * This file is subject to the terms and conditions of the GNU Library General
5 * Public License. See the file "COPYING.LIB" in the main directory of this
6 * archive for more details.
7 *
8 * Non-LGPL License also available as part of VisualDSP++
9 * http://www.analog.com/processors/resources/crosscore/visualDspDevSoftware.html
10 */
11
12#include <sysdep.h>
13
14/* void *memcpy(void *dest, const void *src, size_t n);
15 * R0 = To Address (dest) (leave unchanged to form result)
16 * R1 = From Address (src)
17 * R2 = count
18 *
19 * Note: Favours word alignment
20 */
21
22.text
23
24.align 2
25
26.weak _memcpy
27ENTRY(_memcpy)
28	[--SP] = P3;
29	P0 = R0;              /* P0 = To address */
30	P3 = R1;              /* P3 = From Address */
31	P2 = R2;              /* P2 = count */
32	CC = R2 <= 7(IU);
33	IF CC JUMP .Ltoo_small;
34	I0 = R1;
35	R3 = R1 | R0;         /* OR addresses together */
36	R3 <<= 30;            /* check bottom two bits */
37	CC =  AZ;             /* AZ set if zero. */
38	IF !CC JUMP .Lbytes;  /* Jump if addrs not aligned. */
39	P1 = P2 >> 2;         /* count = n/4 */
40	P1 += -1;
41	R3 =  3;
42	R2 = R2 & R3;         /* remainder */
43	P2 = R2;              /* set remainder */
44	R1 = [I0++];
45#if !defined(__WORKAROUND_AVOID_DAG1)
46	LSETUP (.Lquad_loop, .Lquad_loop) LC0=P1;
47.Lquad_loop:	MNOP || [P0++] = R1 || R1 = [I0++];
48#else
49	LSETUP (.Lquad_loop_s, .Lquad_loop_e) LC0=P1;
50.Lquad_loop_s:	[P0++] = R1;
51.Lquad_loop_e:	R1 = [I0++];
52#endif
53	[P0++] = R1;
54
55	CC = P2 == 0;         /* any remaining bytes? */
56	P3 = I0;              /* Ammend P3 for remaining copy */
57	IF !CC JUMP .Lbytes;
58	P3 = [SP++];
59	RTS;
60
61.Ltoo_small:
62	CC = P2 == 0;          /* Check zero count */
63	IF CC JUMP .Lfinished; /* very unlikely */
64
65.Lbytes:
66	LSETUP (.Lbyte_loop_s, .Lbyte_loop_e) LC0=P2;
67.Lbyte_loop_s:	R1 = B[P3++](Z);
68.Lbyte_loop_e:	B[P0++] = R1;
69
70.Lfinished:
71	P3 = [SP++];
72
73	RTS;
74
75.size _memcpy,.-_memcpy
76
77libc_hidden_def (memcpy)
78