Retro68/gcc/newlib/libc/machine/rx/strncpy.S
2012-03-27 01:51:53 +02:00

19 lines
565 B
ArmAsm

.file "strncpy.S"
.section .text
.global _strncpy
.type _strncpy,@function
_strncpy:
mov r1, r4 ; Save a copy of the dest pointer.
mov r3, r5 ; Save a copy of the byte count
smovu ; Copy the bytes
cmp #0, r3 ; If we have copied the number of bytes requested
beq 1f ; then skip the next bit:
add r4, r5, r1 ; Point to the last byte that we are supposed to write.
sub r3, r1 ; Subtract the number of bytes left to be written.
mov #0, r2 ; Fill the remaining bytes with NULs,
sstr.b
1:
mov r4, r1 ; Return the destination pointer
rts