m68k/fpsp040/util.S

12 |	g_rndpr: returns the rounding precision.
48 |					;largest -ext
70 |	ovf_r_k --- overflow result calculation
74 | This forces the destination precision to be extended
86 |	ovf_r_x2 --- overflow result calculation
93 | This sets the round precision according to the user's FPCR unless the
96 | If the instruction is fsgldiv of fsglmul, the rounding precision must be
97 | extended.  If the instruction is not fsgldiv or fsglmul but a force-
98 | precision instruction, the rounding precision is then set to the force
99 | precision.
109 	beql	ovff_sgl		|force precision is single
111 	beql	ovff_dbl		|force precision is double
136 | Inst is either fsgldiv or fsglmul.  Force extended precision.
149 | The precision is in the fpcr.
152 	bfextu	FPCR_MODE(%a6){#0:#2},%d0 |set round precision
157 |	ovf_r_x3 --- overflow result calculation
164 | This sets the round precision according to the destination size.
170 |				;is the rounding precision
173 |	ovf_res --- overflow result calculation
182 	lsll	#2,%d0		|move round precision to d0{3:2}
192 	leal	EXT_PINF,%a1	|answer is +/- infinity
196 	leal	EXT_PLRG,%a1	|answer is +/- large number
223 	leal	EXT_PINF,%a1	|answer is +/- infinity
227 	leal	DBL_PLRG,%a1	|answer is +/- large number
254 	leal	EXT_PINF,%a1	|answer is +/-  infinity
258 	leal	SGL_PLRG,%a1	|answer is +/- large number
301 |	get_fline --- get f-line opcode of interrupted instruction
303 |	Returns opcode in the low word of d0.
307 	movel	#0,-(%a7)	|reserve a word on the stack
308 	leal	2(%a7),%a1	|point to low word of temporary
314 |	g_rndpr --- put rounding precision in d0{1:0}
317 |		00 - extended
318 |		01 - single
319 |		10 - double
322 | get rounding precision (cmdreg3b{6:5})
325 |	get destination format - this is the also the rounding precision
332 |		use precision from FPCR{7:6}
337 |	     use precision in FPCR{7:6}
350 | is the same as the rounding precision.  Pass results from g_dfmtou.
358 	movel	CMDREG3B(%a6),%d0	|rounding precision in d0{10:9}
361 	beql	unff_sgl	|force precision is single
362 	cmpil	#0x3,%d0		|force precision is double
390 |	cmdreg3b	return	     precision
391 |	--------	------	     ---------
413 | Get rounding precision set in FPCR{7:6}.
416 	movel	USER_FPCR(%a6),%d0 |rounding precision bits in d0{7:6}
420 |	g_opcls --- put opclass in d0{2:0}
433 |	g_dfmtou --- put destination format in d0{1:0}
439 |		extended  010 -> 00
440 |		single    001 -> 01
441 |		double    101 -> 10
482 |	UNF_SUB --- underflow result calculation
485 |	d0	contains round precision
489 |	a0	points to correct internal extended precision result.
512 	lsll	#2,%d0		|move round precision to d0{3:2}
522 	leal	EXT_PZRO,%a1	|answer is +/- zero
526 	leal	EXT_PZRO,%a1	|answer is +/- zero
554 	leal	DBL_PZRO,%a1	|answer is +/- zero
558 	leal	DBL_PZRO,%a1	|answer is +/- zero
586 	leal	SGL_PZRO,%a1	|answer is +/- zero
590 	leal	SGL_PZRO,%a1	|answer is +/- zero
627 |	reg_dest --- write byte, word, or long data to Dn
635 |       -----------------------------------------------
637 |       -----------------------------------------------
640 |		0 - Byte
641 |		1 - Word
642 |		2 - Long/Single