multiplication-pt1.ibcm.txt

Mem	Loc'n	Label	Opcode	Addr	Comments
					push the return address onto stack
4002	27	mult	store	tmp	store the return address into tmp
3001	28		load	sptr	load the stack pointer
5004	29		add	store	create a store instruction
402c	2a		store	pos3	store the store inst into pos3
3002	2b		load	tmp	load up the value to push onto stack
b000	2c	pos3	nop		will hold the push-to-stack inst
3001	2d		load	sptr	load the stack pointer
6007	2e		sub	one	decrement it
4001	2f		store	sptr	store it back
					set possible return value of zero
3006	30		load	zero	load zero into the accumulator
400a	31		store	retval	if we are returning, store zero in 
					the return value
					get the 2nd parameter, compare to 0
3001	32		load	sptr	load the stack pointer
5003	33		add	load	create a load instruction
5009	34		add	three	move to the pos of the 2nd parameter
4036	35		store	pos4	store the load instruction into pos4
b000	36	pos4	nop		will hold inst to load 2nd parameter
4002	37		store	tmp	store it in tmp for use on line 049
d03a	38		jmpe	ret	if 0, we're done with the recursion
c046	39		jmp	recurse	otherwise call ourselves recursively
					in order to return, we need to 
					create a jump inst, clean up the 
					stack, and return 0
3001	3a	ret	load	sptr	load the stack pointer
5003	3b		add	load	create a load instruction
5007	3c		add	one	move to the pos of return address
403e	3d		store	pos5	store the load instruction into pos5
b000	3e	pos5	nop		will hold inst to load return addr
5005	3f		add	jmp	create a jump instruction
4045	40		store	pos6	store the jmp instruction into pos6
3001	41		load	sptr	load the stack pointer
5007	42		add	one	add one to 'remove' the return addr
4001	43		store	sptr	store it back
300a	44		load	retval	load the return value
b000	45	pos6	nop		will hold the jmp (return) inst;
					to call ourselves recursively, we
					push the 2 parameters onto the stack
					stack, then call with brl.
					load 2nd parameter, decrement it,
					then push it onto the stack
3001	46	recurse	load	sptr	load the stack pointer
5004	47		add	store	create a store instruction