6b13f685e
 김민수
BSP 최초 추가
|
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
|
/* MN10300 Optimised simple memory to memory copy
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <asm/cache.h>
.section .text
.balign L1_CACHE_BYTES
###############################################################################
#
# void *memcpy(void *dst, const void *src, size_t n)
#
###############################################################################
.globl memcpy
.type memcpy,@function
memcpy:
movm [d2,d3],(sp)
mov d0,(12,sp)
mov d1,(16,sp)
mov (20,sp),d2 # count
mov d0,a0 # dst
mov d1,a1 # src
mov d0,e3 # the return value
cmp +0,d2
beq memcpy_done # return if zero-length copy
# see if the three parameters are all four-byte aligned
or d0,d1,d3
or d2,d3
and +3,d3
bne memcpy_1 # jump if not
# we want to transfer as much as we can in chunks of 32 bytes
cmp +31,d2
bls memcpy_4_remainder # 4-byte aligned remainder
movm [exreg1],(sp)
add -32,d2
mov +32,d3
memcpy_4_loop:
mov (a1+),d0
mov (a1+),d1
mov (a1+),e0
mov (a1+),e1
mov (a1+),e4
mov (a1+),e5
mov (a1+),e6
mov (a1+),e7
mov d0,(a0+)
mov d1,(a0+)
mov e0,(a0+)
mov e1,(a0+)
mov e4,(a0+)
mov e5,(a0+)
mov e6,(a0+)
mov e7,(a0+)
sub d3,d2
bcc memcpy_4_loop
movm (sp),[exreg1]
add d3,d2
beq memcpy_4_no_remainder
memcpy_4_remainder:
# cut 4-7 words down to 0-3
cmp +16,d2
bcs memcpy_4_three_or_fewer_words
mov (a1+),d0
mov (a1+),d1
mov (a1+),e0
mov (a1+),e1
mov d0,(a0+)
mov d1,(a0+)
mov e0,(a0+)
mov e1,(a0+)
add -16,d2
beq memcpy_4_no_remainder
# copy the remaining 1, 2 or 3 words
memcpy_4_three_or_fewer_words:
cmp +8,d2
bcs memcpy_4_one_word
beq memcpy_4_two_words
mov (a1+),d0
mov d0,(a0+)
memcpy_4_two_words:
mov (a1+),d0
mov d0,(a0+)
memcpy_4_one_word:
mov (a1+),d0
mov d0,(a0+)
memcpy_4_no_remainder:
# check we copied the correct amount
# TODO: REMOVE CHECK
sub e3,a0,d2
mov (20,sp),d1
cmp d2,d1
beq memcpy_done
break
break
break
memcpy_done:
mov e3,a0
ret [d2,d3],8
# handle misaligned copying
memcpy_1:
add -1,d2
mov +1,d3
setlb # setlb requires the next insns
# to occupy exactly 4 bytes
sub d3,d2
movbu (a1),d0
movbu d0,(a0)
add_add d3,a1,d3,a0
lcc
mov e3,a0
ret [d2,d3],8
memcpy_end:
.size memcpy, memcpy_end-memcpy
|