linux/arch/h8300/lib/memset.S

71 lines
858 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/* 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