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Trailing-Edge - PDP-10 Archives - bb-bt99h-bb - mthdbl.c13
There is 1 other file named mthdbl.c13 in the archive. Click here to see a list.
 REP 4/1	;13C1
		TV	MTHDBL	DOUBLE PRECISION ROUTINES ,2(4011)
 WIT
		TV	MTHDBL	DOUBLE PRECISION ROUTINES ,2(4020)
 INS 111/1	;13C2
	4020	DCE	17-Dec-85
		The GFLOATING exponentiation routine uses an incorrect method of
		getting the exponent of the magnitude of certain intermediate 
		GFLOATING numbers. A MOVM on the first word of the double word 
		value is used followed by stripping out the exponent field. 
		This does not work for all negative GFLOATING numbers where the 
		mantissa part in the first word is all zero (the first 
		non-zero bit of the mantissa is in the second word). Due to the 
		fact that these errors occur in an intermediate calculation, 
		it is impossible to specify the class of input numbers which 
		will result in this problem.
 REP 241/13	;13C3
	WOK2:	SETZ	G2,			;ZERO G2
		MOVM	G1,T2			;GET HIGH ORDER OF W
 WIT
	WOK2:	SKIPGE	G1,T2			;[4020] GET |W|
		DMOVN	G1,T2			;[4020] THE HARD WAY (IF NEGATIVE)
		SETZ	G2,			;ZERO G2
 REP 256/13	;13C4
		MOVM	T0,T4			;SAVE A COPY OF ABS(W)
 WIT
		SKIPGE	T0,T4			;[4020] SAVE A COPY OF ABS(W)
		DMOVN	T0,T4			;[4020] THE HARD WAY (IF NEGATIVE)
 REP 271/13	;13C5
		MOVM	T4,T2			;SAVE A COPY OF ABS(W2)
 WIT
		SKIPGE	T4,T2			;[4020] SAVE A COPY OF ABS(W2)
		DMOVN	T4,T2			;[4020] THE HARD WAY (IF NEGATIVE)
 SUM 248247