linux/arch/blackfin/lib/strncpy.S

53 lines
794 B
ArmAsm

/*
* Copyright 2005-2010 Analog Devices Inc.
*
* Licensed under the ADI BSD license or the GPL-2 (or later)
*/
#include <linux/linkage.h>
/* void *strncpy(char *dest, const char *src, size_t n);
* R0 = address (dest)
* R1 = address (src)
* R2 = size
* Returns a pointer to the destination string dest
*/
#ifdef CONFIG_STRNCPY_L1
.section .l1.text
#else
.text
#endif
.align 2
ENTRY(_strncpy)
CC = R2 == 0;
if CC JUMP 4f;
P0 = R0 ; /* dst*/
P1 = R1 ; /* src*/
1:
R1 = B [P1++] (Z);
B [P0++] = R1;
CC = R1;
if ! cc jump 2f;
R2 += -1;
CC = R2 == 0;
if ! cc jump 1b (bp);
jump 4f;
2:
/* if src is shorter than n, we need to null pad bytes in dest */
R1 = 0;
3:
R2 += -1;
CC = R2 == 0;
if cc jump 4f;
B [P0++] = R1;
jump 3b;
4:
RTS;
ENDPROC(_strncpy)