;
; Computes sum from i = 1 to N, placing result in sum.
; The algorithm used is the straightforward one, not that used by Gauss.
;

0x0100		;			.org 0x0100
0x011101110101	; 0x0100	gauss:	subge sum,sum,next
0x010d010d0102	; 0x0101		subge i,i,next
0x010d010c0103	; 0x0102	loop:	subge,i,neg1,next
0x010e010e0104	; 0x0103		subge tmp,tmp,next
0x010e01100105	; 0x0104		subge tmp,N,next
0x010f010f0106	; 0x0105		subge k,k,next
0x010f010e0107	; 0x0106		subge k,tmp,next
0x010f010d0109	; 0x0107		subge k,i,next
0x000000000000	; 0x0108	ret:	subge 0,0,0	; placeholder
0x010f010f010a	; 0x0109		subge k,k,next
0x010f010d010b	; 0x010a		subge k,i,next
0x0111010f0102	; 0x010b		subge sum,k,loop
		;			sum = sum - k = sum + i;
		;			sum >= 0 must be true, so always
		;			goes to loop (unless overflow)
0xffffffffffff	; 0x010c	neg1:	.word -1
0x000000000000	; 0x010d	i:	.word 0
0x000000000000	; 0x010e	tmp:	.word 0
0x000000000000	; 0x010f	k:	.word 0
0x000000000000	; 0x0110	N:	.word 0	; (input)
0x000000000000	; 0x0111	sum:	.word 0	; (output)