swap.s

PowerPC 的 Diab C源码。包括启动程序crt0.s

; swap.s: assembly "swap" function for Bubble Sort example: PowerPC 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:
        stwu            r1,-8(r1)   ; Set up stack frame. See "Stack layout"
        mfspr           r0,8        ;  in the PowerPC Target User's Manual.
        stw             r0,12(r1)
        
        lwz             r4,0(r3)    ; temp = array[0]
        lwz             r5,4(r3)    ; array[0] = array[1]
        stw             r5,0(r3)
        stw             r4,4(r3)    ; array[1] = temp 

        lwz             r0,12(r1)
        mtspr           8,r0
        addi            r1,r1,8
        blr