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
|
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2013 Regents of the University of California
*/
#include <linux/linkage.h>
#include <asm/asm.h>
/* void *memcpy(void *, const void *, size_t) */
ENTRY(__memcpy)
WEAK(memcpy)
move t6, a0 /* Preserve return value */
/* Defer to byte-oriented copy for small sizes */
sltiu a3, a2, 128
bnez a3, 4f
/* Use word-oriented copy only if low-order bits match */
andi a3, t6, SZREG-1
andi a4, a1, SZREG-1
bne a3, a4, 4f
beqz a3, 2f /* Skip if already aligned */
/*
* Round to nearest double word-aligned address
* greater than or equal to start address
*/
andi a3, a1, ~(SZREG-1)
addi a3, a3, SZREG
/* Handle initial misalignment */
sub a4, a3, a1
1:
lb a5, 0(a1)
addi a1, a1, 1
sb a5, 0(t6)
addi t6, t6, 1
bltu a1, a3, 1b
sub a2, a2, a4 /* Update count */
2:
andi a4, a2, ~((16*SZREG)-1)
beqz a4, 4f
add a3, a1, a4
3:
REG_L a4, 0(a1)
REG_L a5, SZREG(a1)
REG_L a6, 2*SZREG(a1)
REG_L a7, 3*SZREG(a1)
REG_L t0, 4*SZREG(a1)
REG_L t1, 5*SZREG(a1)
REG_L t2, 6*SZREG(a1)
REG_L t3, 7*SZREG(a1)
REG_L t4, 8*SZREG(a1)
REG_L t5, 9*SZREG(a1)
REG_S a4, 0(t6)
REG_S a5, SZREG(t6)
REG_S a6, 2*SZREG(t6)
REG_S a7, 3*SZREG(t6)
REG_S t0, 4*SZREG(t6)
REG_S t1, 5*SZREG(t6)
REG_S t2, 6*SZREG(t6)
REG_S t3, 7*SZREG(t6)
REG_S t4, 8*SZREG(t6)
REG_S t5, 9*SZREG(t6)
REG_L a4, 10*SZREG(a1)
REG_L a5, 11*SZREG(a1)
REG_L a6, 12*SZREG(a1)
REG_L a7, 13*SZREG(a1)
REG_L t0, 14*SZREG(a1)
REG_L t1, 15*SZREG(a1)
addi a1, a1, 16*SZREG
REG_S a4, 10*SZREG(t6)
REG_S a5, 11*SZREG(t6)
REG_S a6, 12*SZREG(t6)
REG_S a7, 13*SZREG(t6)
REG_S t0, 14*SZREG(t6)
REG_S t1, 15*SZREG(t6)
addi t6, t6, 16*SZREG
bltu a1, a3, 3b
andi a2, a2, (16*SZREG)-1 /* Update count */
4:
/* Handle trailing misalignment */
beqz a2, 6f
add a3, a1, a2
/* Use word-oriented copy if co-aligned to word boundary */
or a5, a1, t6
or a5, a5, a3
andi a5, a5, 3
bnez a5, 5f
7:
lw a4, 0(a1)
addi a1, a1, 4
sw a4, 0(t6)
addi t6, t6, 4
bltu a1, a3, 7b
ret
5:
lb a4, 0(a1)
addi a1, a1, 1
sb a4, 0(t6)
addi t6, t6, 1
bltu a1, a3, 5b
6:
ret
END(__memcpy)
|
