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
| /* SPDX-License-Identifier: GPL-2.0 */
| /*
| * memscan.S: Optimized memscan for the Sparc.
| *
| * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
| */
|
| #include <asm/export.h>
|
| /* In essence, this is just a fancy strlen. */
|
| #define LO_MAGIC 0x01010101
| #define HI_MAGIC 0x80808080
|
| .text
| .align 4
| .globl __memscan_zero, __memscan_generic
| .globl memscan
| EXPORT_SYMBOL(__memscan_zero)
| EXPORT_SYMBOL(__memscan_generic)
| __memscan_zero:
| /* %o0 = addr, %o1 = size */
| cmp %o1, 0
| bne,a 1f
| andcc %o0, 3, %g0
|
| retl
| nop
|
| 1:
| be mzero_scan_word
| sethi %hi(HI_MAGIC), %g2
|
| ldsb [%o0], %g3
| mzero_still_not_word_aligned:
| cmp %g3, 0
| bne 1f
| add %o0, 1, %o0
|
| retl
| sub %o0, 1, %o0
|
| 1:
| subcc %o1, 1, %o1
| bne,a 1f
| andcc %o0, 3, %g0
|
| retl
| nop
|
| 1:
| bne,a mzero_still_not_word_aligned
| ldsb [%o0], %g3
|
| sethi %hi(HI_MAGIC), %g2
| mzero_scan_word:
| or %g2, %lo(HI_MAGIC), %o3
| sethi %hi(LO_MAGIC), %g3
| or %g3, %lo(LO_MAGIC), %o2
| mzero_next_word:
| ld [%o0], %g2
| mzero_next_word_preloaded:
| sub %g2, %o2, %g2
| mzero_next_word_preloaded_next:
| andcc %g2, %o3, %g0
| bne mzero_byte_zero
| add %o0, 4, %o0
|
| mzero_check_out_of_fuel:
| subcc %o1, 4, %o1
| bg,a 1f
| ld [%o0], %g2
|
| retl
| nop
|
| 1:
| b mzero_next_word_preloaded_next
| sub %g2, %o2, %g2
|
| /* Check every byte. */
| mzero_byte_zero:
| ldsb [%o0 - 4], %g2
| cmp %g2, 0
| bne mzero_byte_one
| sub %o0, 4, %g3
|
| retl
| mov %g3, %o0
|
| mzero_byte_one:
| ldsb [%o0 - 3], %g2
| cmp %g2, 0
| bne,a mzero_byte_two_and_three
| ldsb [%o0 - 2], %g2
|
| retl
| sub %o0, 3, %o0
|
| mzero_byte_two_and_three:
| cmp %g2, 0
| bne,a 1f
| ldsb [%o0 - 1], %g2
|
| retl
| sub %o0, 2, %o0
|
| 1:
| cmp %g2, 0
| bne,a mzero_next_word_preloaded
| ld [%o0], %g2
|
| retl
| sub %o0, 1, %o0
|
| mzero_found_it:
| retl
| sub %o0, 2, %o0
|
| memscan:
| __memscan_generic:
| /* %o0 = addr, %o1 = c, %o2 = size */
| cmp %o2, 0
| bne,a 0f
| ldub [%o0], %g2
|
| b,a 2f
| 1:
| ldub [%o0], %g2
| 0:
| cmp %g2, %o1
| be 2f
| addcc %o2, -1, %o2
| bne 1b
| add %o0, 1, %o0
| 2:
| retl
| nop
|
|
