source: trunk/minix/lib/i86/int64/sub64u.s@ 10

!       sub64u() - unsigned from 64 bit subtraction     Author: Kees J. Bot
!                                                               24 Dec 1995
.sect .text
.define _sub64u, _sub64ul

_sub64u:                        ! u64_t sub64u(u64_t i, unsigned j);
        push    bp
        mov     bp, sp
        xor     cx, cx
        jmp     0f
_sub64ul:                       ! u64_t sub64ul(u64_t i, unsigned long j);
        push    bp
        mov     bp, sp
        mov     cx, 16(bp)
0:      mov     bx, 4(bp)
        mov     ax, 6(bp)
        sub     ax, 14(bp)
        mov     (bx), ax
        mov     ax, 8(bp)
        sbb     ax, cx
        mov     2(bx), ax
        mov     ax, 10(bp)
        sbb     ax, #0
        mov     4(bx), ax
        mov     ax, 12(bp)
        sbb     ax, #0
        mov     6(bx), ax
        mov     ax, bx
        pop     bp
        ret