view fib.s68 @ 756:e1dc98f7ed9f

Preserve scratch2 when using it as a temporary in memory read functions. This fixes a bunch of issues with the Z80 core and possibly some issues with the 68K core as well
author Michael Pavone <pavone@retrodev.com>
date Sat, 27 Jun 2015 13:18:55 -0700
parents f664eeb55cb4
children 2455662378ed f7fe240a7da6
line wrap: on
line source

    dc.l $0, start
start:
	moveq #36, d0
	bsr fib
	illegal
fib:
	cmp.l #2, d0
	blt base
	subq.l #1, d0
	move.l d0, -(a7)
	bsr fib
	move.l (a7), d1
	exg d0, d1
	move.l d1, (a7)
	subq.l #1, d0
	bsr fib
	move.l (a7)+, d1
	add.l d1, d0
	rts
base:
	moveq #1, d0
	rts