.pg
.x subq
.x subq3
.lt
------------------------------------------------------------------------
SUBQ	sub,dif
SUBQ3	sub,min,dif
------------------------------------------------------------------------
.el
.b 3
These macros perform quadword subtraction.
.b
These macros will produce inline code to perform the quadword subtraction.
After the subtraction is performed, r0 will contain the following values:
.b
.lt
	-1	if dif < 0
	0	if dif = 0
	1	if dif > 0
.el
.b
The SUBQ macro is equivalent to the expression:
.b
.lt
	dif = sub - dif
.el
.b
and the SUBQ3 macro is equivalent to the expression:
.b
.lt
	dif = sub - min
.el
.b
For example:
.b
.lt
	subq3	sub,min,dif
.el
.b
will produce the following code:
.b
.lt
		movq	min,dif
		subl	sub,dif
		sbcw	4+sub,4+dif
		tstl	4+dif
		blss	30001$
		bgtr	30002$
		tstl	dif
		bnequ	30002$
		clrl	r0
		brb	30003$
	30001$:	movl	#-1,r0
		brb	30003$
	30002$:	movl	#1,r0
	30003$:
.el
.b
See also ADDQ, ADDQ3, CMPQ, DIVQ4, MULQ, MULQ3, and TSTQ.