ifpsp060/src/ilsp.S

139 	mov.l		0x10(%a6), %d6		# get dividend lo
160 	negx.l		%d6			# complement signed dividend
170 	tst.l		%d6			# is (lo(dividend) == 0), too
173 	cmp.l		%d7,%d6			# is (divisor <= lo(dividend))
176 	exg		%d5,%d6			# q = 0, r = dividend
180 	tdivu.l		%d7, %d5:%d6		# it's only a 32/32 bit div!
209 	cmpi.l		%d6, &0x80000000	# will (-quot) fit in 32 bits?
212 	neg.l		%d6			# make (-quot) 2's comp
217 	btst		&0x1f, %d6		# will (+quot) fit in 32 bits?
225 	tst.l		%d6			# may set 'N' ccode bit
244 	mov.l		0x10(%a6), %d6		# get dividend lo
276 # in %d6. The divisor must be in the variable ddivisor, and the		#
278 # The quotient is returned in %d6, remainder in %d5, unless the		#
300 	swap		%d6			# get u3 to lsw position
301 	mov.w		%d6, %d5		# rb + u3
306 	swap		%d6			# get u4
307 	mov.w		%d6, %d5		# rb + u4
315 	mov.l		%d1, %d6		# and quotient
335 	lsl.l		&0x1, %d6		# shift u4,u3 with overflow to u2
361 	mov.l		%d6, -(%sp)
362 	clr.w		%d6			# word u3 left
363 	swap		%d6			# in lsw position
375 	mov.w		%d6,%d4			# insert lower word (U3)
380 #	add.l		%d6, %d4		# (U1U2 - V1q) + U3
389 	mov.l		%d5, -(%sp)		# save %d5 (%d6 already saved)
390 	mov.l		%d1, %d6
391 	swap		%d6			# shift answer to ms 3 words
395 	mov.l		%d6, %d3
397 	mov.l		(%sp)+, %d6
398 	sub.l		%d3, %d6
409 	add.l		%d3, %d6		# aligned with 3rd word of dividend
423 	swap		%d6
424 	mov.w		%d6, %d5
425 	clr.w		%d6
432 	mov.w		%d5, %d6
433 	swap		%d6
439 	lsr.l		&0x1, %d5		# shift into %d6
440 	roxr.l		&0x1, %d6
443 	mov.l		%d6, %d5		# remainder
444 	mov.l		DDQUOTIENT(%a6), %d6	# quotient
448 # factors for the 32X32->64 multiplication are in %d5 and %d6.
449 # returns 64 bit result in %d5 (hi) %d6(lo).
453 	mov.l		%d6, %d2
454 	mov.l		%d6, %d3
458 	mulu.w		%d5, %d6		# %d6 <- lsw*lsw
464 	swap		%d6
465 	add.w		%d5, %d6		# add msw of l*l to lsw of m*l product
467 	add.w		%d2, %d6		# add in lsw of other m*l product
469 	swap		%d6			# %d6 is low 32 bits of final product