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; UPD ID= 1720 on 2/22/79 at 10:19 AM by W:<WRIGHT>
TITLE	SIZ23 FOR LIBOL V12
SUBTTL	CHECK 2-WORD ITEM FOR SIZE ERROR		AL BLACKINGTON/CAM



;THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY ONLY BE USED
;  OR COPIED IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE.
;
;COPYRIGHT (C) 1974, 1979 BY DIGITAL EQUIPMENT CORPORATION


	SEARCH	LBLPRM

	HISEG

ENTRY SIZE.2	;LITERAL TO BE COMPARED AGAINST IS 1 WORD.
ENTRY SIZE.3	;LITERAL TO BE COMPARED AGAINST IS 2 WORDS.

PP=17	;PUSH-DOWN POINTER
PA=16	;INPUT UUO
TA=13	;HIGH-ORDER AC
TB=14	;LOW-ORDER AC
TC=15	;TEMP
TH=10	;HIGH-ORDER OF LITERAL
TL=11	;LOW-ORDER OF LITERAL

EXTERNAL SZERA.	;SIZE ERROR INDICATOR
EXTERNAL OVFLO.	;OVERFLOW INDICATION

;EDIT HISTORY
;**** VERSION 12 *****
;DAW	20-FEB-79	[554] ENCLOSE QUAD-WORD ROUTINES IN BIS CONDITIONAL
;		THIS IS ACTUALLY PART OF COBOL EDIT 634-- CUSTOMERS MUST
;		REBUILD BOTH COBOL AND LIBOL

;CALLING SEQUENCE:
;	MOVEI	PA,<FIRST OF 2 AC'S TO BE TESTED>
;	PUSHJ	PP,SIZE.2  (OR SIZE.3)
;	XWD	<EXIT IF SIZE ERROR>,<ADDRESS OF VALUE TO BE COMPARED AGAINST>

SIZE.2:	MOVE	TC,@0(PP)	;PICK UP XWD
	MOVEI	TH,0		;HIGH ORDER HALF OF LITERAL IS ZERO
	MOVE	TL,0(TC)	;PICK UP LOW ORDER HALF
	JRST	SIZ.23

SIZE.3:	MOVE	TC,@0(PP)	;PICK UP XWD
IFN BIS,<
	DMOVE	TH,0(TC)	;PICK UP LITERAL
>
IFE BIS,<
	MOVE	TH,0(TC)	;PICK UP HIGH ORDER OF LITERAL
	MOVE	TL,1(TC)	;PICK UP LOW ORDER OF LITERAL
>


SIZ.23:	SKIPE	OVFLO.		;WAS THERE ANY OVERFLOW?
	JRST	SIZ23E		;YES
	MOVE	TB,1(PA)	;PICK UP LOW-ORDER AC
	SKIPGE	TA,0(PA)	;IS HIGH-ORDER PART NEGATIVE?
IFN BIS,<
	DMOVN	TA,TA		;YES, MAKE POSITIVE
>
IFE BIS,<
	JRST	SIZ23G		;YES--IT WILL HAVE TO BE MADE POSITIVE
>

SIZ23A:	CAML	TA,TH		;COMPARE THE HIGH-ORDER HALVES
	JRST	SIZ23C		;AC IS NOT SMALLER THAN LITERAL

SIZ23B:	AOS	(PP)		;RETURN TO WORD FOLLOWING THE XWD
	POPJ	PP,

SIZ23C:	CAME	TA,TH		;ARE HIGH-ORDER PARTS EQUAL?
	JRST	SIZ23E		;NO

	CAMGE	TB,TL		;COMPARE LOW-ORDER HALVES
	JRST	SIZ23B		;AC LESS THAN LITERAL--OK

SIZ23E:	HLRM	TC,0(PP)	;NO--SIZE ERROR--SET UP RETURN
	SETOM	SZERA.		;SET ERROR INDICATOR
	POPJ	PP,

IFE BIS,<
SIZ23G:	SETCA	TA,		;NEGATE AC (IN ORDER TO GET POSITIVE)
	TLO	TB,1B18		;INSURE THAT LOW-ORDER PART HAS SIGN
	MOVMS	TB		;GET MAGNITUDE OF LOW-ORDER HALF
	TLZ	TB,1B18		;INSURE SIGN BIT IS ZERO
	JUMPN	TB,SIZ23A	;IF LOW-ORDER HALF NOT ZERO, OK
	AOJA	TA,SIZ23A	;LOW-ORDER HALF ZERO, BUMP HIGH-ORDER
>

SUBTTL	CHECK 4-WORD ITEM FOR SIZE ERROR IN LOWER 2-WORDS

IFN BIS,<			;[554] PUT IN BIS CONDITIONAL
ENTRY SIZE.4	;LITERAL TO BE COMPARED AGAINST IS 1 WORD.
ENTRY SIZE.5	;LITERAL TO BE COMPARED AGAINST IS 2 WORDS.

SIZE.4:	PUSHJ	PP,SIZE4T	;TEST HIGH 2-WORDS
	JRST	SIZE.2		;TEST LOWER 2-WORDS

SIZE.5:	PUSHJ	PP,SIZE4T	;TEST HIGH 2-WORDS
	JRST	SIZE.3		;TEST LOWER 2-WORDS

SIZE4T:	SKIPE	TH,0(PA)	;BOTH WORDS MUST BE 0
	AOJN	TH,SIZE4F	;OR -1
	SKIPE	TL,1(PA)
	AOJN	TL,SIZE4F
	ADDI	PA,2		;POINT TO LOWER 2-WORDS
	POPJ	PP,

SIZE4F:	POP	PP,(PP)
	MOVE	TC,@0(PP)	;PICKUP XWD
	JRST	SIZ23E		;FAILED
>;END IFN BIS			;[554]


	END