summaryrefslogtreecommitdiffstats
path: root/arch/h8300/lib/memset.S
blob: 4549a64c5b79655a5991ec77db03cbd2c96ac5c6 (plain)
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
/* memset.S */

#include <asm/linkage.h>

#if defined(__H8300H__) 
	.h8300h
#endif
#if defined(__H8300S__) 
	.h8300s
#endif
	.text

.global	_memset

;;void *memset(*ptr, int c, size_t count)
;; ptr = er0
;; c   = er1(r1l)
;; count = er2
_memset:
	btst	#0,r0l
	beq	2f

	;; odd address
1:
	mov.b	r1l,@er0
	adds	#1,er0
	dec.l	#1,er2
	beq	6f

	;; even address
2:
	mov.l	er2,er3
	cmp.l	#4,er2
	blo	4f
	;; count>=4 -> count/4
#if defined(__H8300H__)
	shlr.l	er2
	shlr.l	er2
#endif
#if defined(__H8300S__)
	shlr.l	#2,er2
#endif
	;; byte -> long
	mov.b	r1l,r1h
	mov.w	r1,e1
3:
	mov.l	er1,@er0
	adds	#4,er0
	dec.l	#1,er2
	bne	3b
4:
	;; count % 4
	and.b	#3,r3l
	beq	6f
5:
	mov.b	r1l,@er0
	adds	#1,er0
	dec.b	r3l
	bne	5b
6:
	rts
OpenPOWER on IntegriCloud