sort

sort.c

#include <stdio.h>
#include <stdlib.h>

void sort(int *ap, int n);
#if 0
void sort(int *ap, int n)
{
    int bubbled;
    int i;

    do {
        bubbled = 0;
        for (i = 1; i < n; i++) {
            if (ap[i - 1] > ap[i]) {
                int t = ap[i - 1];
                ap[i - 1] = ap[i];
                ap[i] = t;
                bubbled = 1;
            }
        }
    } while (bubbled);

}
#endif

int main()
{

    int n = 10;
    int *ap;
    int *bp;
    int i;

    ap = (int *) malloc(sizeof(int) * n);
    bp = (int *) malloc(sizeof(int) * n);

    for (;;) {
        for (i = 0; i < n; i++) {
            ap[i] = rand() % 10;
            bp[i] = ap[i];
        }

        sort(ap, n);

        for (i = 0; i < n; i++) {
            fprintf(stderr, "ap'[%d] = %d\n", i, bp[i]);

        }
        for (i = 0; i < n; i++) {
            fprintf(stderr, "ap[%d] = %d\n", i, ap[i]);
        }
        for (i = 1; i < n; i++) {
            if (ap[i - 1] > ap[i]) {
                fprintf(stderr, "ap[%d] = %d > ap[%d] = %d\n", i - 1,
                        ap[i - 1], i, ap[i]);
                free(bp);
                free(ap);
                return 0;
            }
        }
    }


    free(bp);
    free(ap);
    return 0;
}

sort.S

    .globl  sort
sort:
    push    %ebp
    mov     %esp, %ebp
    pushl   %esi
    pushl   %ebx
    
1:
    xorl    %ebx, %ebx

    movl    8(%ebp), %esi
    movl    12(%ebp), %ecx

    leal    (%esi, %ecx, 4), %esi
    negl    %ecx
    addl    $1, %ecx
2:
    movl    -4(%esi,%ecx,4), %eax
    movl    (%esi,%ecx,4), %edx

    cmpl     %edx, %eax

    jle      3f

    movl    %edx, -4(%esi,%ecx,4)
    movl    %eax, (%esi,%ecx,4)

    orl     $1, %ebx
3:
    addl    $1, %ecx
    jnz     2b

    testl   %ebx, %ebx
    jnz     1b

    popl    %ebx
    popl    %esi
    popl    %ebp
    ret