swap.s

M68K 的 Diab C源码。包括启动程序crt0.s

; swap.s: assembly "swap" function for Bubble Sort example: 68K target.
;
; Equivalent C code:
;
;       void swap (int array[])
;       {
;           int temp = array[0];
;           array[0] = array[1];
;           array[1] = temp;
;       }
        
        .name   "swap.s"
        .section .text2,,c      ; Locate the code in the ".text2" section.

        .align  4
        .xdef   _swap

_swap:
        link    a6,#-0          ; Maintain stack frame for debugging.
        
        move.l  8(a6),a0        ; address of "array" to a0
        move.l  (a0),d0         ; "array[0]" to d0 ("temp")
        move.l  4(a0),(a0)      ; "array[1]" to "array[0]"
        move.l  d0,4(a0)        ; d0 ("temp") to "array[1]"

        unlk    a6              ; Match for "link" above.
        rts