1/*
2 *  arch/s390/kernel/strncpy.S
3 *    S390 strncpy routine
4 *
5 *  S390 version
6 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
7 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
8 */
9
10/*
11 * R2 = address of destination
12 * R3 = address of source string
13 * R4 = max number of bytes to copy
14 */
15        .globl   strncpy
16strncpy:
17        LGR     1,2            # don't touch address in R2
18	LTR     4,4
19        JZ      strncpy_exit   # 0 bytes -> nothing to do
20	SGR     0,0
21strncpy_loop:
22        ICM     0,1,0(3)       # ICM sets the cc, IC does not
23	LA      3,1(3)
24        STC     0,0(1)
25	LA      1,1(1)
26        JZ      strncpy_exit   # ICM inserted a 0x00
27        BRCTG   4,strncpy_loop # R4 -= 1, jump to strncpy_loop if > 0
28strncpy_exit:
29        BR      14
30
31