.area   _CODE

__mulint_rrx_s::
        pop     af
        pop     hl
        pop     de
        push    de
        push    hl
        push    af

        ;; Fall through

__muluchar_rrx_hds::
__mulint_rrx_hds::
	;; Parameters:
	;;	hl, de (left, right irrelevant)
	ld	b,h
	ld	c,l

	;; 16-bit multiplication
	;;
	;; Entry conditions
	;; bc = multiplicand
	;; de = multiplier
	;;
	;; Exit conditions
	;; hl = less significant word of product
	;;
	;; Register used: AF,BC,DE,HL
__mul16::
	xor	a,a
	ld	l,a
	or	a,b
	ld	b,#16

        ;; Optimise for the case when this side has 8 bits of data or
        ;; less.  This is often the case with support address calls.
        jr      NZ,2$
        ld      b,#8
        ld      a,c
1$:
        ;; Taken from z88dk, which originally borrowed from the
        ;; Spectrum rom.
        add     hl,hl
2$:
        rl      c
        rla                     ;DLE 27/11/98
        jr      NC,3$
        add     hl,de
3$:
        djnz    1$
        ret