1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Hartvig Ekner <hartvige@mips.com>, 2002.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <features.h>
/*#include <sysdep.h>*/
#include <endian.h>
#include "sysdep.h"
#ifdef __mips64
#error mips32 code being compiled for mips64!
#endif
/* void *memcpy(void *s1, const void *s2, size_t n); */
#if __BYTE_ORDER == __BIG_ENDIAN
# define LWHI lwl /* high part is left in big-endian */
# define SWHI swl /* high part is left in big-endian */
# define LWLO lwr /* low part is right in big-endian */
# define SWLO swr /* low part is right in big-endian */
#else
# define LWHI lwr /* high part is right in little-endian */
# define SWHI swr /* high part is right in little-endian */
# define LWLO lwl /* low part is left in little-endian */
# define SWLO swl /* low part is left in little-endian */
#endif
ENTRY (memcpy)
.set noreorder
slti t0, a2, 8 # Less than 8?
bne t0, zero, L(last8)
move v0, a0 # Setup exit value before too late
xor t0, a1, a0 # Find a0/a1 displacement
andi t0, 0x3
bne t0, zero, L(shift) # Go handle the unaligned case
subu t1, zero, a1
andi t1, 0x3 # a0/a1 are aligned, but are we
beq t1, zero, L(chk8w) # starting in the middle of a word?
subu a2, t1
LWHI t0, 0(a1) # Yes we are... take care of that
addu a1, t1
SWHI t0, 0(a0)
addu a0, t1
L(chk8w):
andi t0, a2, 0x1f # 32 or more bytes left?
beq t0, a2, L(chk1w)
subu a3, a2, t0 # Yes
addu a3, a1 # a3 = end address of loop
move a2, t0 # a2 = what will be left after loop
L(lop8w):
lw t0, 0(a1) # Loop taking 8 words at a time
lw t1, 4(a1)
lw t2, 8(a1)
lw t3, 12(a1)
lw t4, 16(a1)
lw t5, 20(a1)
lw t6, 24(a1)
lw t7, 28(a1)
addiu a0, 32
addiu a1, 32
sw t0, -32(a0)
sw t1, -28(a0)
sw t2, -24(a0)
sw t3, -20(a0)
sw t4, -16(a0)
sw t5, -12(a0)
sw t6, -8(a0)
bne a1, a3, L(lop8w)
sw t7, -4(a0)
L(chk1w):
andi t0, a2, 0x3 # 4 or more bytes left?
beq t0, a2, L(last8)
subu a3, a2, t0 # Yes, handle them one word at a time
addu a3, a1 # a3 again end address
move a2, t0
L(lop1w):
lw t0, 0(a1)
addiu a0, 4
addiu a1, 4
bne a1, a3, L(lop1w)
sw t0, -4(a0)
L(last8):
blez a2, L(lst8e) # Handle last 8 bytes, one at a time
addu a3, a2, a1
L(lst8l):
lb t0, 0(a1)
addiu a0, 1
addiu a1, 1
bne a1, a3, L(lst8l)
sb t0, -1(a0)
L(lst8e):
jr ra # Bye, bye
nop
L(shift):
subu a3, zero, a0 # Src and Dest unaligned
andi a3, 0x3 # (unoptimized case...)
beq a3, zero, L(shft1)
subu a2, a3 # a2 = bytes left
LWHI t0, 0(a1) # Take care of first odd part
LWLO t0, 3(a1)
addu a1, a3
SWHI t0, 0(a0)
addu a0, a3
L(shft1):
andi t0, a2, 0x3
subu a3, a2, t0
addu a3, a1
L(shfth):
LWHI t1, 0(a1) # Limp through, word by word
LWLO t1, 3(a1)
addiu a0, 4
addiu a1, 4
bne a1, a3, L(shfth)
sw t1, -4(a0)
b L(last8) # Handle anything which may be left
move a2, t0
.set reorder
END (memcpy)
libc_hidden_def(memcpy)
|
