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
|
/*
* String handling functions.
*
* Copyright IBM Corp. 2012
*/
#include <linux/linkage.h>
#include <asm/export.h>
/*
* void *memmove(void *dest, const void *src, size_t n)
*/
ENTRY(memmove)
ltgr %r4,%r4
lgr %r1,%r2
bzr %r14
clgr %r2,%r3
jnh .Lmemmove_forward
la %r5,0(%r4,%r3)
clgr %r2,%r5
jl .Lmemmove_reverse
.Lmemmove_forward:
aghi %r4,-1
srlg %r0,%r4,8
ltgr %r0,%r0
jz .Lmemmove_rest
.Lmemmove_loop:
mvc 0(256,%r1),0(%r3)
la %r1,256(%r1)
la %r3,256(%r3)
brctg %r0,.Lmemmove_loop
.Lmemmove_rest:
larl %r5,.Lmemmove_mvc
ex %r4,0(%r5)
br %r14
.Lmemmove_reverse:
aghi %r4,-1
.Lmemmove_reverse_loop:
ic %r0,0(%r4,%r3)
stc %r0,0(%r4,%r1)
brctg %r4,.Lmemmove_reverse_loop
ic %r0,0(%r4,%r3)
stc %r0,0(%r4,%r1)
br %r14
.Lmemmove_mvc:
mvc 0(1,%r1),0(%r3)
EXPORT_SYMBOL(memmove)
/*
* memset implementation
*
* This code corresponds to the C construct below. We do distinguish
* between clearing (c == 0) and setting a memory array (c != 0) simply
* because nearly all memset invocations in the kernel clear memory and
* the xc instruction is preferred in such cases.
*
* void *memset(void *s, int c, size_t n)
* {
* if (likely(c == 0))
* return __builtin_memset(s, 0, n);
* return __builtin_memset(s, c, n);
* }
*/
ENTRY(memset)
ltgr %r4,%r4
bzr %r14
ltgr %r3,%r3
jnz .Lmemset_fill
aghi %r4,-1
srlg %r3,%r4,8
ltgr %r3,%r3
lgr %r1,%r2
jz .Lmemset_clear_rest
.Lmemset_clear_loop:
xc 0(256,%r1),0(%r1)
la %r1,256(%r1)
brctg %r3,.Lmemset_clear_loop
.Lmemset_clear_rest:
larl %r3,.Lmemset_xc
ex %r4,0(%r3)
br %r14
.Lmemset_fill:
stc %r3,0(%r2)
cghi %r4,1
lgr %r1,%r2
ber %r14
aghi %r4,-2
srlg %r3,%r4,8
ltgr %r3,%r3
jz .Lmemset_fill_rest
.Lmemset_fill_loop:
mvc 1(256,%r1),0(%r1)
la %r1,256(%r1)
brctg %r3,.Lmemset_fill_loop
.Lmemset_fill_rest:
larl %r3,.Lmemset_mvc
ex %r4,0(%r3)
br %r14
.Lmemset_xc:
xc 0(1,%r1),0(%r1)
.Lmemset_mvc:
mvc 1(1,%r1),0(%r1)
EXPORT_SYMBOL(memset)
/*
* memcpy implementation
*
* void *memcpy(void *dest, const void *src, size_t n)
*/
ENTRY(memcpy)
ltgr %r4,%r4
bzr %r14
aghi %r4,-1
srlg %r5,%r4,8
ltgr %r5,%r5
lgr %r1,%r2
jnz .Lmemcpy_loop
.Lmemcpy_rest:
larl %r5,.Lmemcpy_mvc
ex %r4,0(%r5)
br %r14
.Lmemcpy_loop:
mvc 0(256,%r1),0(%r3)
la %r1,256(%r1)
la %r3,256(%r3)
brctg %r5,.Lmemcpy_loop
j .Lmemcpy_rest
.Lmemcpy_mvc:
mvc 0(1,%r1),0(%r3)
EXPORT_SYMBOL(memcpy)
|
