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
|
TEXT memset(SB),$0
#define BDNZ BC 16,0,
MOVW R3, p+0(FP) /* R3 is pointer */
/*
* performance:
* about 100mbytes/sec (8k blocks) on a 603/105 without L2 cache
* drops to 40mbytes/sec (10k blocks) and 28mbytes/sec with 32k blocks
*/
MOVW n+8(FP), R4 /* R4 is count */
CMP R4, $0
BLE ret
MOVW c+4(FP), R5 /* R5 is char */
/*
* create 16 copies of c in R5 .. R8
*/
RLWNM $0, R5, $0xff, R5
RLWMI $8, R5, $0xff00, R5
RLWMI $16, R5, $0xffff0000, R5
MOVW R5, R6
MOVW R5, R7
MOVW R5, R8
/*
* let STSW do the work for 16 characters or less; aligned and unaligned
*/
CMP R4, $16
BLE out
/*
* store enough bytes to align pointer
*/
ANDCC $7,R3, R9
BEQ l2
SUBC R9, $8, R9
MOVW R9, XER
STSW R5, (R3)
ADD R9, R3
SUB R9, R4
/*
* store 16 at a time while there's room
* STSW was used here originally, but it's `completion serialised'
*/
l2:
SRAWCC $4, R4, R9
BLE out
MOVW R9, CTR
l3:
MOVW R5, 0(R3)
ADD $8, R3, R10
MOVW R6, 4(R3)
MOVW R7, 0(R10)
ADD $8, R10, R3
MOVW R8, 4(R10)
BDNZ l3
RLWNMCC $0, R4, $15, R4 /* residue */
BEQ ret
/*
* store up to 16 bytes from R5 .. R8; aligned and unaligned
*/
out:
MOVW R4, XER
STSW R5, (R3)
ret:
MOVW 0(FP), R3
RETURN
END
|
