ifpsp060/src/ilsp.S

75 #	0x8(sp)  = hi(dividend)						#
76 #	0xc(sp)  = lo(dividend)						#
138 	mov.l		0xc(%a6), %d5		# get dividend hi
139 	mov.l		0x10(%a6), %d6		# get dividend lo
152 # save the sign of the dividend
153 # make dividend unsigned if it's negative
155 	tst.l		%d5			# chk sign of hi(dividend)
156 	slt		NDIVIDEND(%a6)		# save sign of dividend
160 	negx.l		%d6			# complement signed dividend
164 #	- is (dividend == 0) ?
165 #	- is (hi(dividend) == 0 && (divisor <= lo(dividend))) ? (32-bit div)
167 	tst.l		%d5			# is (hi(dividend) == 0)
170 	tst.l		%d6			# is (lo(dividend) == 0), too
171 	beq.w		lddone			# yes, so (dividend == 0)
173 	cmp.l		%d7,%d6			# is (divisor <= lo(dividend))
176 	exg		%d5,%d6			# q = 0, r = dividend
186 #	- is hi(dividend) >= divisor ? if yes, then overflow
200 	beq.b		ldcc			# as dividend.
201 	neg.l		%d5			# sgn(rem) = sgn(dividend)
241 # the result should be the unchanged dividend
243 	mov.l		0xc(%a6), %d5		# get dividend hi
244 	mov.l		0x10(%a6), %d6		# get dividend lo
272 # where U,V are words of the quadword dividend and longword divisor,	#
275 # The most sig. longword of the 64 bit dividend must be in %d5, least	#
279 # v (overflow) bit is set in the saved %ccr. If overflow, the dividend	#
289 # Since the divisor is only a word (and larger than the mslw of the dividend),
292 # dividing the divisor word into each dividend word. In this case,
295 # longword of the dividend as (0) remainder (see Knuth) and merely complete
321 # which is divided into a 3 digit (word) dividend to get one quotient
322 # digit (word). After subtraction, the dividend is shifted and the
343 	mov.l		%d5, %d2		# dividend mslw
388 # the 3 digit (word) result with the current dividend words
396 	mov.l		(%sp)+, %d5		# restore dividend
402 # need to add back divisor longword to current ms 3 digits of dividend
404 # divisor, dividend selection.
409 	add.l		%d3, %d6		# aligned with 3rd word of dividend
413 	swap		%d3			# aligned with 2nd word of dividend
419 # (subtracted) dividend