libc/newlib/libc/machine/rx/strcat.S

23 lines
670 B
ArmAsm

.file "strcat.S"
.section .text
.global _strcat
.type _strcat,@function
_strcat:
;; On entry: r1 => Destination
;; r2 => Source
mov r1, r4 ; Save a copy of the dest pointer.
mov r2, r5 ; Save a copy of the source pointer.
mov #0, r2 ; Search for the NUL byte.
mov #-1, r3 ; Limit on the number of bytes examined.
suntil.b ; Find the end of the destination string.
sub #1, r1 ; suntil.b leaves r1 pointing to the byte beyond the match.
mov #-1, r3 ; Set a limit on the number of bytes copied.
mov r5, r2 ; Restore the source pointer.
smovu ; Copy source to destination
mov r4, r1 ; Return the original dest pointer.
rts