blob: 3065be2b440ce0f92436a9e0e9cc39f62b921907 [file] [log] [blame]
/*
* arch/s390/kernel/strncpy.S
* S390 strncpy routine
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
*/
/*
* R2 = address of destination
* R3 = address of source string
* R4 = max number of bytes to copy
*/
.globl strncpy
strncpy:
LR 1,2 # don't touch address in R2
LTR 4,4
JZ strncpy_exit # 0 bytes -> nothing to do
SR 0,0
strncpy_loop:
ICM 0,1,0(3) # ICM sets the cc, IC does not
LA 3,1(3)
STC 0,0(1)
LA 1,1(1)
JZ strncpy_exit # ICM inserted a 0x00
BRCT 4,strncpy_loop # R4 -= 1, jump to strncpy_loop if > 0
strncpy_exit:
BR 14