swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
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Tip revision: cbfe8fa6cd672011c755c3cd85c9ffd4e2d10a6f authored by Linus Torvalds on 26 July 2015, 19:26:21 UTC
Linux 4.2-rc4
Tip revision: cbfe8fa
memset.S
/* memset.S */

#include <asm/linkage.h>

#if defined(CONFIG_CPU_H8300H)
	.h8300h
#endif
#if defined(CONFIG_CPU_H8S)
	.h8300s
#endif
	.text

.global	memset
.global	clear_user

;;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(CONFIG_CPU_H8300H)
	shlr.l	er2
	shlr.l	er2
#endif
#if defined(CONFIG_CPU_H8S)
	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

clear_user:
	mov.l	er1, er2
	sub.l	er1, er1
	bra	memset

	.end
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