.TITLE	MINUS		
; JEFFREY KODOSKY	ARL	NOV75
;
; SUBR
; ENTRY:	1 ARG		<NUM>
; EXIT:		1 ARG		<NUM>
; ERRORS:	NONE
; CALLS:	ATM2N
;		R2ATM
;		I2ATM
; R2,R3 PRESERVED
	.GLOBL	MINUS,ZMINUS,QATM2N,QR2ATM,QI2ATM
MINUS:	QATM2N
	BCS	MINUS2
	NEG	@SP	;NEGATE INTEGER
	BVC	MINUS1
	CLR	@SP	;CONVERT TO REAL IF OVERFLOW
	MOV	#^F32768.,-(SP)	;-NEGMAX
MINUS0:	QR2ATM
	.WORD	0
MINUS1:	QI2ATM
	.WORD	0
MINUS2:	MOV	@SP,R0	;NEGATE A REAL NUMBER OR INFINITY
	ADD	#100000,@SP
	ASL	R0
	BNE	MINUS0
MINUS4:	MOV	2(SP),R0;LOOK AT LO ORDER
	BNE	MINUS6	;JUMP IF INFINITY
MINUS5:	CLR	@SP	;MAKE A CLEAN ZERO
	BR	MINUS0
MINUS6:	MOV	#-1,2(SP)	;MAKE A CLEAN INFINITY
	BR	MINUS0
ZMINUS=.-MINUS
	.END