ifpsp060/src/pfpsp.S

446 set ovfl_bit,		4			# overflow
453 set aovfl_bit,		6			# accrued overflow bit
474 set ovfl_mask,		0x00001000		# overflow exception mask
481 set aovfl_mask,		0x00000040		# accrued overflow
611 #	On the 060, if an FP overflow is present as the result of any	#
612 # instruction, the 060 will take an overflow exception whether the	#
623 # _real_ovfl() so that the operating system enabled overflow handler	#
625 #	Two other conditions exist. First, if overflow was disabled	#
630 # overflow was disabled and the trace exception was enabled, this	#
721 # the exceptional possibilities we have left ourselves with are ONLY overflow
722 # and inexact. and, the inexact is such that overflow occurred and was disabled
738 # overflow is enabled AND overflow, of course, occurred. so, we have the EXOP
755 # overflow occurred but is disabled. meanwhile, inexact is enabled. Therefore,
863 # _real_unfl() so that the operating system enabled overflow handler	#
969 # the exceptional possibilities we have left ourselves with are ONLY overflow
970 # and inexact. and, the inexact is such that overflow occurred and was disabled
988 # overflow is enabled AND overflow, of course, occurred. so, we have the EXOP
1360 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
1366 	bra.w		fu_in_exc_ovfl		# go insert overflow frame
1391 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did disabled overflow occur?
1620 # if a disabled overflow occurred and inexact was enabled but the result
1622 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
1938 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # was overflow set?
1969 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did disabled overflow occur?
2652 # no exception occurred. now, did a disabled, exact overflow occur with inexact
2653 # enabled? if so, then we have to stuff an overflow frame into the FPU.
2654 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
2669 # the enabled exception was inexact. so, if it occurs with an overflow
2670 # or underflow that was disabled, then we have to force an overflow or
2672 	btst		&ovfl_bit,FPSR_EXCEPT(%a6) # did overflow occur?
6253 	bcc.b		scc_clr			# no mantissa overflow
6946 #	ovf_res(): routine to produce the default overflow result of	#
6967 #	The default overflow result can be determined by the sign of	#
7056 #	ovf_res() - create default overflow result for sgl/dbl precision#
7073 #	fp0 : intermediate underflow or overflow result if		#
7084 #	For sgl or dbl precision, overflow or underflow can occur. If	#
7341 # would cause either an underflow or overflow. these cases are handled
7348 	cmpi.w		%d0,&SGL_HI		# will operand overflow?
7444 # it's definitely an overflow so call ovf_res to get the correct answer
7460 # overflow result. DON'T save the returned ccodes from ovf_res() since
7466 	fmovm.x		(%a0),&0x80		# load default overflow result
7494 # move out MAY overflow:
7517 	bra.w		fout_sgl_ovfl		# yes; go handle overflow
7579 # would cause either an underflow or overflow. these cases are handled
7586 	cmpi.w		%d0,&DBL_HI		# will operand overflow?
7665 # it's definitely an overflow so call ovf_res to get the correct answer
7681 # overflow result. DON'T save the returned ccodes from ovf_res() since
7687 	fmovm.x		(%a0),&0x80		# load default overflow result
7705 # move out MAY overflow:
7728 	bra.w		fout_dbl_ovfl		# yes; go handle overflow
7962 #	ovf_res() - return default overflow result			#
7981 # an exception. If so, return the default overflow/underflow result	#
8038 	beq.w		fmul_may_ovfl		# result may rnd to overflow
8039 	blt.w		fmul_ovfl		# result will overflow
8047 # - the result of the multiply operation will neither overflow nor underflow.
8082 # - the result of the multiply operation is an overflow.
8086 # - if overflow or inexact is enabled, we need a multiply result rounded to
8166 # - the result of the multiply operation MAY overflow.
8186 	fbge.w		fmul_ovfl_tst		# yes; overflow has occurred
8188 # no, it didn't overflow; we have correct result
8197 # - if overflow or inexact is enabled, we need a multiply result rounded to
8457 #	ovf_res() - return default overflow result			#
8509 # or overflow because of rounding to the correct precision. so...
8576 	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
8578 	blt.w		fin_sd_ovfl		# yes; go handle overflow
8581 # operand will NOT overflow or underflow when moved into the fp reg file
8619 	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
8621 	blt.w		fin_sd_ovfl		# yes; go handle overflow
8671 # operand WILL overflow.
8725 # the move in MAY overflow. so...
8740 	fbge.w		fin_sd_ovfl_tst		# yes; overflow has occurred
8742 # no, it didn't overflow; we have correct result
8779 #	ovf_res() - return default overflow result			#
8798 # an exception. If so, return the default overflow/underflow result	#
8811 	long		0x3fff - 0x7ffe		# ext overflow exponent
8812 	long		0x3fff - 0x407e		# sgl overflow exponent
8813 	long		0x3fff - 0x43fe		# dbl overflow exponent
8860 	cmp.l		%d0,(tbl_fdiv_ovfl.b,%pc,%d1.w*4) # will result overflow?
8861 	ble.w		fdiv_may_ovfl		# result will overflow
9232 #	ovf_res() - return default overflow result			#
9249 # and an actual fneg performed to see if overflow/underflow would have	#
9250 # occurred. If so, return default underflow/overflow result. Else,	#
9282 # or overflow because of rounding to the correct precision. so...
9356 	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
9358 	blt.w		fneg_sd_ovfl		# yes; go handle overflow
9361 # operand will NOT overflow or underflow when moved in to the fp reg file
9399 	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
9401 	blt.w		fneg_sd_ovfl		# yes; go handle overflow
9451 # operand WILL overflow.
9520 	fbge.w		fneg_sd_ovfl_tst	# yes; overflow has occurred
9522 # no, it didn't overflow; we have correct result
9852 #	ovf_res() - calculate overflow result				#
9868 #	Double and single precision can overflow and underflow. First,	#
9905 # or overflow because of rounding to the correct precision. so...
9974 	cmpi.l		%d0,&0x3fff-0x407e	# will move in overflow?
9976 	blt.w		fabs_sd_ovfl		# yes; go handle overflow
9979 # operand will NOT overflow or underflow when moved in to the fp reg file
10017 	cmpi.l		%d0,&0x3fff-0x43fe	# will move in overflow?
10019 	blt.w		fabs_sd_ovfl		# yes; go handle overflow
10066 # operand WILL overflow.
10135 	fbge.w		fabs_sd_ovfl_tst	# yes; overflow has occurred
10137 # no, it didn't overflow; we have correct result
10364 #	ovf_res() - return default overflow result			#
10383 # an exception. If so, return the default overflow/underflow result	#
10417 	beq.w		fsglmul_may_ovfl	# result may rnd to overflow
10418 	blt.w		fsglmul_ovfl		# result will overflow
10515 	fbge.w		fsglmul_ovfl_tst	# yes; overflow has occurred
10517 # no, it didn't overflow; we have correct result
10705 #	ovf_res() - return default overflow result			#
10724 # an exception. If so, return the default overflow/underflow result	#
10816 	cmp.l		%d1,&0x7fff		# did divide overflow?
11040 #	ovf_res() - return default overflow result			#
11120 	cmp.l		%d2,(tbl_fadd_ovfl.b,%pc,%d1.w*4) # is it an overflow?
11493 #	ovf_res() - return default overflow result			#
11573 	cmp.l		%d2,(tbl_fsub_ovfl.b,%pc,%d1.w*4) # is it an overflow?
11940 #	ovf_res() - return default overflow result			#
11958 # an exception. If so, return the default overflow/underflow result	#
12037 	cmpi.l		%d0,&0x3fff-0x407f	# will move in overflow?
12039 	blt.w		fsqrt_sd_ovfl		# yes; go handle overflow
12042 # operand will NOT overflow or underflow when moved in to the fp reg file
12082 	cmpi.l		%d0,&0x3fff-0x43ff	# will move in overflow?
12084 	blt.w		fsqrt_sd_ovfl		# yes; go handle overflow
12148 # operand WILL overflow.
12206 	bne.w		fsqrt_sd_ovfl		# yes, so overflow
12220 	fbge.w		fsqrt_sd_ovfl_tst	# yes; overflow has occurred
12222 # no, it didn't overflow; we have correct result
12972 #	Note: this operation can never overflow.			#
12978 #	Note: this operation can never overflow.			#
13860 #     to overflow.  Only a negative iscale can cause this, so