xref: /openbmc/linux/arch/m68k/fpsp040/res_func.S (revision e00d82d0)
1|
2|	res_func.sa 3.9 7/29/91
3|
4| Normalizes denormalized numbers if necessary and updates the
5| stack frame.  The function is then restored back into the
6| machine and the 040 completes the operation.  This routine
7| is only used by the unsupported data type/format handler.
8| (Exception vector 55).
9|
10| For packed move out (fmove.p fpm,<ea>) the operation is
11| completed here; data is packed and moved to user memory.
12| The stack is restored to the 040 only in the case of a
13| reportable exception in the conversion.
14|
15|
16|		Copyright (C) Motorola, Inc. 1990
17|			All Rights Reserved
18|
19|       For details on the license for this file, please see the
20|       file, README, in this same directory.
21
22RES_FUNC:    |idnt    2,1 | Motorola 040 Floating Point Software Package
23
24	|section	8
25
26#include "fpsp.h"
27
28sp_bnds:	.short	0x3f81,0x407e
29		.short	0x3f6a,0x0000
30dp_bnds:	.short	0x3c01,0x43fe
31		.short	0x3bcd,0x0000
32
33	|xref	mem_write
34	|xref	bindec
35	|xref	get_fline
36	|xref	round
37	|xref	denorm
38	|xref	dest_ext
39	|xref	dest_dbl
40	|xref	dest_sgl
41	|xref	unf_sub
42	|xref	nrm_set
43	|xref	dnrm_lp
44	|xref	ovf_res
45	|xref	reg_dest
46	|xref	t_ovfl
47	|xref	t_unfl
48
49	.global	res_func
50	.global	p_move
51
52res_func:
53	clrb	DNRM_FLG(%a6)
54	clrb	RES_FLG(%a6)
55	clrb	CU_ONLY(%a6)
56	tstb	DY_MO_FLG(%a6)
57	beqs	monadic
58dyadic:
59	btstb	#7,DTAG(%a6)	|if dop = norm=000, zero=001,
60|				;inf=010 or nan=011
61	beqs	monadic		|then branch
62|				;else denorm
63| HANDLE DESTINATION DENORM HERE
64|				;set dtag to norm
65|				;write the tag & fpte15 to the fstack
66	leal	FPTEMP(%a6),%a0
67
68	bclrb	#sign_bit,LOCAL_EX(%a0)
69	sne	LOCAL_SGN(%a0)
70
71	bsr	nrm_set		|normalize number (exp will go negative)
72	bclrb	#sign_bit,LOCAL_EX(%a0) |get rid of false sign
73	bfclr	LOCAL_SGN(%a0){#0:#8}	|change back to IEEE ext format
74	beqs	dpos
75	bsetb	#sign_bit,LOCAL_EX(%a0)
76dpos:
77	bfclr	DTAG(%a6){#0:#4}	|set tag to normalized, FPTE15 = 0
78	bsetb	#4,DTAG(%a6)	|set FPTE15
79	orb	#0x0f,DNRM_FLG(%a6)
80monadic:
81	leal	ETEMP(%a6),%a0
82	btstb	#direction_bit,CMDREG1B(%a6)	|check direction
83	bne	opclass3			|it is a mv out
84|
85| At this point, only opclass 0 and 2 possible
86|
87	btstb	#7,STAG(%a6)	|if sop = norm=000, zero=001,
88|				;inf=010 or nan=011
89	bne	mon_dnrm	|else denorm
90	tstb	DY_MO_FLG(%a6)	|all cases of dyadic instructions would
91	bne	normal		|require normalization of denorm
92
93| At this point:
94|	monadic instructions:	fabs  = $18  fneg   = $1a  ftst   = $3a
95|				fmove = $00  fsmove = $40  fdmove = $44
96|				fsqrt = $05* fssqrt = $41  fdsqrt = $45
97|				(*fsqrt reencoded to $05)
98|
99	movew	CMDREG1B(%a6),%d0	|get command register
100	andil	#0x7f,%d0			|strip to only command word
101|
102| At this point, fabs, fneg, fsmove, fdmove, ftst, fsqrt, fssqrt, and
103| fdsqrt are possible.
104| For cases fabs, fneg, fsmove, and fdmove goto spos (do not normalize)
105| For cases fsqrt, fssqrt, and fdsqrt goto nrm_src (do normalize)
106|
107	btstl	#0,%d0
108	bne	normal			|weed out fsqrt instructions
109|
110| cu_norm handles fmove in instructions with normalized inputs.
111| The routine round is used to correctly round the input for the
112| destination precision and mode.
113|
114cu_norm:
115	st	CU_ONLY(%a6)		|set cu-only inst flag
116	movew	CMDREG1B(%a6),%d0
117	andib	#0x3b,%d0		|isolate bits to select inst
118	tstb	%d0
119	beql	cu_nmove	|if zero, it is an fmove
120	cmpib	#0x18,%d0
121	beql	cu_nabs		|if $18, it is fabs
122	cmpib	#0x1a,%d0
123	beql	cu_nneg		|if $1a, it is fneg
124|
125| Inst is ftst.  Check the source operand and set the cc's accordingly.
126| No write is done, so simply rts.
127|
128cu_ntst:
129	movew	LOCAL_EX(%a0),%d0
130	bclrl	#15,%d0
131	sne	LOCAL_SGN(%a0)
132	beqs	cu_ntpo
133	orl	#neg_mask,USER_FPSR(%a6) |set N
134cu_ntpo:
135	cmpiw	#0x7fff,%d0	|test for inf/nan
136	bnes	cu_ntcz
137	tstl	LOCAL_HI(%a0)
138	bnes	cu_ntn
139	tstl	LOCAL_LO(%a0)
140	bnes	cu_ntn
141	orl	#inf_mask,USER_FPSR(%a6)
142	rts
143cu_ntn:
144	orl	#nan_mask,USER_FPSR(%a6)
145	movel	ETEMP_EX(%a6),FPTEMP_EX(%a6)	|set up fptemp sign for
146|						;snan handler
147
148	rts
149cu_ntcz:
150	tstl	LOCAL_HI(%a0)
151	bnel	cu_ntsx
152	tstl	LOCAL_LO(%a0)
153	bnel	cu_ntsx
154	orl	#z_mask,USER_FPSR(%a6)
155cu_ntsx:
156	rts
157|
158| Inst is fabs.  Execute the absolute value function on the input.
159| Branch to the fmove code.  If the operand is NaN, do nothing.
160|
161cu_nabs:
162	moveb	STAG(%a6),%d0
163	btstl	#5,%d0			|test for NaN or zero
164	bne	wr_etemp		|if either, simply write it
165	bclrb	#7,LOCAL_EX(%a0)		|do abs
166	bras	cu_nmove		|fmove code will finish
167|
168| Inst is fneg.  Execute the negate value function on the input.
169| Fall though to the fmove code.  If the operand is NaN, do nothing.
170|
171cu_nneg:
172	moveb	STAG(%a6),%d0
173	btstl	#5,%d0			|test for NaN or zero
174	bne	wr_etemp		|if either, simply write it
175	bchgb	#7,LOCAL_EX(%a0)		|do neg
176|
177| Inst is fmove.  This code also handles all result writes.
178| If bit 2 is set, round is forced to double.  If it is clear,
179| and bit 6 is set, round is forced to single.  If both are clear,
180| the round precision is found in the fpcr.  If the rounding precision
181| is double or single, round the result before the write.
182|
183cu_nmove:
184	moveb	STAG(%a6),%d0
185	andib	#0xe0,%d0			|isolate stag bits
186	bne	wr_etemp		|if not norm, simply write it
187	btstb	#2,CMDREG1B+1(%a6)	|check for rd
188	bne	cu_nmrd
189	btstb	#6,CMDREG1B+1(%a6)	|check for rs
190	bne	cu_nmrs
191|
192| The move or operation is not with forced precision.  Test for
193| nan or inf as the input; if so, simply write it to FPn.  Use the
194| FPCR_MODE byte to get rounding on norms and zeros.
195|
196cu_nmnr:
197	bfextu	FPCR_MODE(%a6){#0:#2},%d0
198	tstb	%d0			|check for extended
199	beq	cu_wrexn		|if so, just write result
200	cmpib	#1,%d0			|check for single
201	beq	cu_nmrs			|fall through to double
202|
203| The move is fdmove or round precision is double.
204|
205cu_nmrd:
206	movel	#2,%d0			|set up the size for denorm
207	movew	LOCAL_EX(%a0),%d1		|compare exponent to double threshold
208	andw	#0x7fff,%d1
209	cmpw	#0x3c01,%d1
210	bls	cu_nunfl
211	bfextu	FPCR_MODE(%a6){#2:#2},%d1	|get rmode
212	orl	#0x00020000,%d1		|or in rprec (double)
213	clrl	%d0			|clear g,r,s for round
214	bclrb	#sign_bit,LOCAL_EX(%a0)	|convert to internal format
215	sne	LOCAL_SGN(%a0)
216	bsrl	round
217	bfclr	LOCAL_SGN(%a0){#0:#8}
218	beqs	cu_nmrdc
219	bsetb	#sign_bit,LOCAL_EX(%a0)
220cu_nmrdc:
221	movew	LOCAL_EX(%a0),%d1		|check for overflow
222	andw	#0x7fff,%d1
223	cmpw	#0x43ff,%d1
224	bge	cu_novfl		|take care of overflow case
225	bra	cu_wrexn
226|
227| The move is fsmove or round precision is single.
228|
229cu_nmrs:
230	movel	#1,%d0
231	movew	LOCAL_EX(%a0),%d1
232	andw	#0x7fff,%d1
233	cmpw	#0x3f81,%d1
234	bls	cu_nunfl
235	bfextu	FPCR_MODE(%a6){#2:#2},%d1
236	orl	#0x00010000,%d1
237	clrl	%d0
238	bclrb	#sign_bit,LOCAL_EX(%a0)
239	sne	LOCAL_SGN(%a0)
240	bsrl	round
241	bfclr	LOCAL_SGN(%a0){#0:#8}
242	beqs	cu_nmrsc
243	bsetb	#sign_bit,LOCAL_EX(%a0)
244cu_nmrsc:
245	movew	LOCAL_EX(%a0),%d1
246	andw	#0x7FFF,%d1
247	cmpw	#0x407f,%d1
248	blt	cu_wrexn
249|
250| The operand is above precision boundaries.  Use t_ovfl to
251| generate the correct value.
252|
253cu_novfl:
254	bsr	t_ovfl
255	bra	cu_wrexn
256|
257| The operand is below precision boundaries.  Use denorm to
258| generate the correct value.
259|
260cu_nunfl:
261	bclrb	#sign_bit,LOCAL_EX(%a0)
262	sne	LOCAL_SGN(%a0)
263	bsr	denorm
264	bfclr	LOCAL_SGN(%a0){#0:#8}	|change back to IEEE ext format
265	beqs	cu_nucont
266	bsetb	#sign_bit,LOCAL_EX(%a0)
267cu_nucont:
268	bfextu	FPCR_MODE(%a6){#2:#2},%d1
269	btstb	#2,CMDREG1B+1(%a6)	|check for rd
270	bne	inst_d
271	btstb	#6,CMDREG1B+1(%a6)	|check for rs
272	bne	inst_s
273	swap	%d1
274	moveb	FPCR_MODE(%a6),%d1
275	lsrb	#6,%d1
276	swap	%d1
277	bra	inst_sd
278inst_d:
279	orl	#0x00020000,%d1
280	bra	inst_sd
281inst_s:
282	orl	#0x00010000,%d1
283inst_sd:
284	bclrb	#sign_bit,LOCAL_EX(%a0)
285	sne	LOCAL_SGN(%a0)
286	bsrl	round
287	bfclr	LOCAL_SGN(%a0){#0:#8}
288	beqs	cu_nuflp
289	bsetb	#sign_bit,LOCAL_EX(%a0)
290cu_nuflp:
291	btstb	#inex2_bit,FPSR_EXCEPT(%a6)
292	beqs	cu_nuninx
293	orl	#aunfl_mask,USER_FPSR(%a6) |if the round was inex, set AUNFL
294cu_nuninx:
295	tstl	LOCAL_HI(%a0)		|test for zero
296	bnes	cu_nunzro
297	tstl	LOCAL_LO(%a0)
298	bnes	cu_nunzro
299|
300| The mantissa is zero from the denorm loop.  Check sign and rmode
301| to see if rounding should have occurred which would leave the lsb.
302|
303	movel	USER_FPCR(%a6),%d0
304	andil	#0x30,%d0		|isolate rmode
305	cmpil	#0x20,%d0
306	blts	cu_nzro
307	bnes	cu_nrp
308cu_nrm:
309	tstw	LOCAL_EX(%a0)	|if positive, set lsb
310	bges	cu_nzro
311	btstb	#7,FPCR_MODE(%a6) |check for double
312	beqs	cu_nincs
313	bras	cu_nincd
314cu_nrp:
315	tstw	LOCAL_EX(%a0)	|if positive, set lsb
316	blts	cu_nzro
317	btstb	#7,FPCR_MODE(%a6) |check for double
318	beqs	cu_nincs
319cu_nincd:
320	orl	#0x800,LOCAL_LO(%a0) |inc for double
321	bra	cu_nunzro
322cu_nincs:
323	orl	#0x100,LOCAL_HI(%a0) |inc for single
324	bra	cu_nunzro
325cu_nzro:
326	orl	#z_mask,USER_FPSR(%a6)
327	moveb	STAG(%a6),%d0
328	andib	#0xe0,%d0
329	cmpib	#0x40,%d0		|check if input was tagged zero
330	beqs	cu_numv
331cu_nunzro:
332	orl	#unfl_mask,USER_FPSR(%a6) |set unfl
333cu_numv:
334	movel	(%a0),ETEMP(%a6)
335	movel	4(%a0),ETEMP_HI(%a6)
336	movel	8(%a0),ETEMP_LO(%a6)
337|
338| Write the result to memory, setting the fpsr cc bits.  NaN and Inf
339| bypass cu_wrexn.
340|
341cu_wrexn:
342	tstw	LOCAL_EX(%a0)		|test for zero
343	beqs	cu_wrzero
344	cmpw	#0x8000,LOCAL_EX(%a0)	|test for zero
345	bnes	cu_wreon
346cu_wrzero:
347	orl	#z_mask,USER_FPSR(%a6)	|set Z bit
348cu_wreon:
349	tstw	LOCAL_EX(%a0)
350	bpl	wr_etemp
351	orl	#neg_mask,USER_FPSR(%a6)
352	bra	wr_etemp
353
354|
355| HANDLE SOURCE DENORM HERE
356|
357|				;clear denorm stag to norm
358|				;write the new tag & ete15 to the fstack
359mon_dnrm:
360|
361| At this point, check for the cases in which normalizing the
362| denorm produces incorrect results.
363|
364	tstb	DY_MO_FLG(%a6)	|all cases of dyadic instructions would
365	bnes	nrm_src		|require normalization of denorm
366
367| At this point:
368|	monadic instructions:	fabs  = $18  fneg   = $1a  ftst   = $3a
369|				fmove = $00  fsmove = $40  fdmove = $44
370|				fsqrt = $05* fssqrt = $41  fdsqrt = $45
371|				(*fsqrt reencoded to $05)
372|
373	movew	CMDREG1B(%a6),%d0	|get command register
374	andil	#0x7f,%d0			|strip to only command word
375|
376| At this point, fabs, fneg, fsmove, fdmove, ftst, fsqrt, fssqrt, and
377| fdsqrt are possible.
378| For cases fabs, fneg, fsmove, and fdmove goto spos (do not normalize)
379| For cases fsqrt, fssqrt, and fdsqrt goto nrm_src (do normalize)
380|
381	btstl	#0,%d0
382	bnes	nrm_src		|weed out fsqrt instructions
383	st	CU_ONLY(%a6)	|set cu-only inst flag
384	bra	cu_dnrm		|fmove, fabs, fneg, ftst
385|				;cases go to cu_dnrm
386nrm_src:
387	bclrb	#sign_bit,LOCAL_EX(%a0)
388	sne	LOCAL_SGN(%a0)
389	bsr	nrm_set		|normalize number (exponent will go
390|				; negative)
391	bclrb	#sign_bit,LOCAL_EX(%a0) |get rid of false sign
392
393	bfclr	LOCAL_SGN(%a0){#0:#8}	|change back to IEEE ext format
394	beqs	spos
395	bsetb	#sign_bit,LOCAL_EX(%a0)
396spos:
397	bfclr	STAG(%a6){#0:#4}	|set tag to normalized, FPTE15 = 0
398	bsetb	#4,STAG(%a6)	|set ETE15
399	orb	#0xf0,DNRM_FLG(%a6)
400normal:
401	tstb	DNRM_FLG(%a6)	|check if any of the ops were denorms
402	bne	ck_wrap		|if so, check if it is a potential
403|				;wrap-around case
404fix_stk:
405	moveb	#0xfe,CU_SAVEPC(%a6)
406	bclrb	#E1,E_BYTE(%a6)
407
408	clrw	NMNEXC(%a6)
409
410	st	RES_FLG(%a6)	|indicate that a restore is needed
411	rts
412
413|
414| cu_dnrm handles all cu-only instructions (fmove, fabs, fneg, and
415| ftst) completely in software without an frestore to the 040.
416|
417cu_dnrm:
418	st	CU_ONLY(%a6)
419	movew	CMDREG1B(%a6),%d0
420	andib	#0x3b,%d0		|isolate bits to select inst
421	tstb	%d0
422	beql	cu_dmove	|if zero, it is an fmove
423	cmpib	#0x18,%d0
424	beql	cu_dabs		|if $18, it is fabs
425	cmpib	#0x1a,%d0
426	beql	cu_dneg		|if $1a, it is fneg
427|
428| Inst is ftst.  Check the source operand and set the cc's accordingly.
429| No write is done, so simply rts.
430|
431cu_dtst:
432	movew	LOCAL_EX(%a0),%d0
433	bclrl	#15,%d0
434	sne	LOCAL_SGN(%a0)
435	beqs	cu_dtpo
436	orl	#neg_mask,USER_FPSR(%a6) |set N
437cu_dtpo:
438	cmpiw	#0x7fff,%d0	|test for inf/nan
439	bnes	cu_dtcz
440	tstl	LOCAL_HI(%a0)
441	bnes	cu_dtn
442	tstl	LOCAL_LO(%a0)
443	bnes	cu_dtn
444	orl	#inf_mask,USER_FPSR(%a6)
445	rts
446cu_dtn:
447	orl	#nan_mask,USER_FPSR(%a6)
448	movel	ETEMP_EX(%a6),FPTEMP_EX(%a6)	|set up fptemp sign for
449|						;snan handler
450	rts
451cu_dtcz:
452	tstl	LOCAL_HI(%a0)
453	bnel	cu_dtsx
454	tstl	LOCAL_LO(%a0)
455	bnel	cu_dtsx
456	orl	#z_mask,USER_FPSR(%a6)
457cu_dtsx:
458	rts
459|
460| Inst is fabs.  Execute the absolute value function on the input.
461| Branch to the fmove code.
462|
463cu_dabs:
464	bclrb	#7,LOCAL_EX(%a0)		|do abs
465	bras	cu_dmove		|fmove code will finish
466|
467| Inst is fneg.  Execute the negate value function on the input.
468| Fall though to the fmove code.
469|
470cu_dneg:
471	bchgb	#7,LOCAL_EX(%a0)		|do neg
472|
473| Inst is fmove.  This code also handles all result writes.
474| If bit 2 is set, round is forced to double.  If it is clear,
475| and bit 6 is set, round is forced to single.  If both are clear,
476| the round precision is found in the fpcr.  If the rounding precision
477| is double or single, the result is zero, and the mode is checked
478| to determine if the lsb of the result should be set.
479|
480cu_dmove:
481	btstb	#2,CMDREG1B+1(%a6)	|check for rd
482	bne	cu_dmrd
483	btstb	#6,CMDREG1B+1(%a6)	|check for rs
484	bne	cu_dmrs
485|
486| The move or operation is not with forced precision.  Use the
487| FPCR_MODE byte to get rounding.
488|
489cu_dmnr:
490	bfextu	FPCR_MODE(%a6){#0:#2},%d0
491	tstb	%d0			|check for extended
492	beq	cu_wrexd		|if so, just write result
493	cmpib	#1,%d0			|check for single
494	beq	cu_dmrs			|fall through to double
495|
496| The move is fdmove or round precision is double.  Result is zero.
497| Check rmode for rp or rm and set lsb accordingly.
498|
499cu_dmrd:
500	bfextu	FPCR_MODE(%a6){#2:#2},%d1	|get rmode
501	tstw	LOCAL_EX(%a0)		|check sign
502	blts	cu_dmdn
503	cmpib	#3,%d1			|check for rp
504	bne	cu_dpd			|load double pos zero
505	bra	cu_dpdr			|load double pos zero w/lsb
506cu_dmdn:
507	cmpib	#2,%d1			|check for rm
508	bne	cu_dnd			|load double neg zero
509	bra	cu_dndr			|load double neg zero w/lsb
510|
511| The move is fsmove or round precision is single.  Result is zero.
512| Check for rp or rm and set lsb accordingly.
513|
514cu_dmrs:
515	bfextu	FPCR_MODE(%a6){#2:#2},%d1	|get rmode
516	tstw	LOCAL_EX(%a0)		|check sign
517	blts	cu_dmsn
518	cmpib	#3,%d1			|check for rp
519	bne	cu_spd			|load single pos zero
520	bra	cu_spdr			|load single pos zero w/lsb
521cu_dmsn:
522	cmpib	#2,%d1			|check for rm
523	bne	cu_snd			|load single neg zero
524	bra	cu_sndr			|load single neg zero w/lsb
525|
526| The precision is extended, so the result in etemp is correct.
527| Simply set unfl (not inex2 or aunfl) and write the result to
528| the correct fp register.
529cu_wrexd:
530	orl	#unfl_mask,USER_FPSR(%a6)
531	tstw	LOCAL_EX(%a0)
532	beq	wr_etemp
533	orl	#neg_mask,USER_FPSR(%a6)
534	bra	wr_etemp
535|
536| These routines write +/- zero in double format.  The routines
537| cu_dpdr and cu_dndr set the double lsb.
538|
539cu_dpd:
540	movel	#0x3c010000,LOCAL_EX(%a0)	|force pos double zero
541	clrl	LOCAL_HI(%a0)
542	clrl	LOCAL_LO(%a0)
543	orl	#z_mask,USER_FPSR(%a6)
544	orl	#unfinx_mask,USER_FPSR(%a6)
545	bra	wr_etemp
546cu_dpdr:
547	movel	#0x3c010000,LOCAL_EX(%a0)	|force pos double zero
548	clrl	LOCAL_HI(%a0)
549	movel	#0x800,LOCAL_LO(%a0)	|with lsb set
550	orl	#unfinx_mask,USER_FPSR(%a6)
551	bra	wr_etemp
552cu_dnd:
553	movel	#0xbc010000,LOCAL_EX(%a0)	|force pos double zero
554	clrl	LOCAL_HI(%a0)
555	clrl	LOCAL_LO(%a0)
556	orl	#z_mask,USER_FPSR(%a6)
557	orl	#neg_mask,USER_FPSR(%a6)
558	orl	#unfinx_mask,USER_FPSR(%a6)
559	bra	wr_etemp
560cu_dndr:
561	movel	#0xbc010000,LOCAL_EX(%a0)	|force pos double zero
562	clrl	LOCAL_HI(%a0)
563	movel	#0x800,LOCAL_LO(%a0)	|with lsb set
564	orl	#neg_mask,USER_FPSR(%a6)
565	orl	#unfinx_mask,USER_FPSR(%a6)
566	bra	wr_etemp
567|
568| These routines write +/- zero in single format.  The routines
569| cu_dpdr and cu_dndr set the single lsb.
570|
571cu_spd:
572	movel	#0x3f810000,LOCAL_EX(%a0)	|force pos single zero
573	clrl	LOCAL_HI(%a0)
574	clrl	LOCAL_LO(%a0)
575	orl	#z_mask,USER_FPSR(%a6)
576	orl	#unfinx_mask,USER_FPSR(%a6)
577	bra	wr_etemp
578cu_spdr:
579	movel	#0x3f810000,LOCAL_EX(%a0)	|force pos single zero
580	movel	#0x100,LOCAL_HI(%a0)	|with lsb set
581	clrl	LOCAL_LO(%a0)
582	orl	#unfinx_mask,USER_FPSR(%a6)
583	bra	wr_etemp
584cu_snd:
585	movel	#0xbf810000,LOCAL_EX(%a0)	|force pos single zero
586	clrl	LOCAL_HI(%a0)
587	clrl	LOCAL_LO(%a0)
588	orl	#z_mask,USER_FPSR(%a6)
589	orl	#neg_mask,USER_FPSR(%a6)
590	orl	#unfinx_mask,USER_FPSR(%a6)
591	bra	wr_etemp
592cu_sndr:
593	movel	#0xbf810000,LOCAL_EX(%a0)	|force pos single zero
594	movel	#0x100,LOCAL_HI(%a0)	|with lsb set
595	clrl	LOCAL_LO(%a0)
596	orl	#neg_mask,USER_FPSR(%a6)
597	orl	#unfinx_mask,USER_FPSR(%a6)
598	bra	wr_etemp
599
600|
601| This code checks for 16-bit overflow conditions on dyadic
602| operations which are not restorable into the floating-point
603| unit and must be completed in software.  Basically, this
604| condition exists with a very large norm and a denorm.  One
605| of the operands must be denormalized to enter this code.
606|
607| Flags used:
608|	DY_MO_FLG contains 0 for monadic op, $ff for dyadic
609|	DNRM_FLG contains $00 for neither op denormalized
610|	                  $0f for the destination op denormalized
611|	                  $f0 for the source op denormalized
612|	                  $ff for both ops denormalized
613|
614| The wrap-around condition occurs for add, sub, div, and cmp
615| when
616|
617|	abs(dest_exp - src_exp) >= $8000
618|
619| and for mul when
620|
621|	(dest_exp + src_exp) < $0
622|
623| we must process the operation here if this case is true.
624|
625| The rts following the frcfpn routine is the exit from res_func
626| for this condition.  The restore flag (RES_FLG) is left clear.
627| No frestore is done unless an exception is to be reported.
628|
629| For fadd:
630|	if(sign_of(dest) != sign_of(src))
631|		replace exponent of src with $3fff (keep sign)
632|		use fpu to perform dest+new_src (user's rmode and X)
633|		clr sticky
634|	else
635|		set sticky
636|	call round with user's precision and mode
637|	move result to fpn and wbtemp
638|
639| For fsub:
640|	if(sign_of(dest) == sign_of(src))
641|		replace exponent of src with $3fff (keep sign)
642|		use fpu to perform dest+new_src (user's rmode and X)
643|		clr sticky
644|	else
645|		set sticky
646|	call round with user's precision and mode
647|	move result to fpn and wbtemp
648|
649| For fdiv/fsgldiv:
650|	if(both operands are denorm)
651|		restore_to_fpu;
652|	if(dest is norm)
653|		force_ovf;
654|	else(dest is denorm)
655|		force_unf:
656|
657| For fcmp:
658|	if(dest is norm)
659|		N = sign_of(dest);
660|	else(dest is denorm)
661|		N = sign_of(src);
662|
663| For fmul:
664|	if(both operands are denorm)
665|		force_unf;
666|	if((dest_exp + src_exp) < 0)
667|		force_unf:
668|	else
669|		restore_to_fpu;
670|
671| local equates:
672	.set	addcode,0x22
673	.set	subcode,0x28
674	.set	mulcode,0x23
675	.set	divcode,0x20
676	.set	cmpcode,0x38
677ck_wrap:
678	| tstb	DY_MO_FLG(%a6)	;check for fsqrt
679	beq	fix_stk		|if zero, it is fsqrt
680	movew	CMDREG1B(%a6),%d0
681	andiw	#0x3b,%d0		|strip to command bits
682	cmpiw	#addcode,%d0
683	beq	wrap_add
684	cmpiw	#subcode,%d0
685	beq	wrap_sub
686	cmpiw	#mulcode,%d0
687	beq	wrap_mul
688	cmpiw	#cmpcode,%d0
689	beq	wrap_cmp
690|
691| Inst is fdiv.
692|
693wrap_div:
694	cmpb	#0xff,DNRM_FLG(%a6) |if both ops denorm,
695	beq	fix_stk		 |restore to fpu
696|
697| One of the ops is denormalized.  Test for wrap condition
698| and force the result.
699|
700	cmpb	#0x0f,DNRM_FLG(%a6) |check for dest denorm
701	bnes	div_srcd
702div_destd:
703	bsrl	ckinf_ns
704	bne	fix_stk
705	bfextu	ETEMP_EX(%a6){#1:#15},%d0	|get src exp (always pos)
706	bfexts	FPTEMP_EX(%a6){#1:#15},%d1	|get dest exp (always neg)
707	subl	%d1,%d0			|subtract dest from src
708	cmpl	#0x7fff,%d0
709	blt	fix_stk			|if less, not wrap case
710	clrb	WBTEMP_SGN(%a6)
711	movew	ETEMP_EX(%a6),%d0		|find the sign of the result
712	movew	FPTEMP_EX(%a6),%d1
713	eorw	%d1,%d0
714	andiw	#0x8000,%d0
715	beq	force_unf
716	st	WBTEMP_SGN(%a6)
717	bra	force_unf
718
719ckinf_ns:
720	moveb	STAG(%a6),%d0		|check source tag for inf or nan
721	bra	ck_in_com
722ckinf_nd:
723	moveb	DTAG(%a6),%d0		|check destination tag for inf or nan
724ck_in_com:
725	andib	#0x60,%d0			|isolate tag bits
726	cmpb	#0x40,%d0			|is it inf?
727	beq	nan_or_inf		|not wrap case
728	cmpb	#0x60,%d0			|is it nan?
729	beq	nan_or_inf		|yes, not wrap case?
730	cmpb	#0x20,%d0			|is it a zero?
731	beq	nan_or_inf		|yes
732	clrl	%d0
733	rts				|then ; it is either a zero of norm,
734|					;check wrap case
735nan_or_inf:
736	moveql	#-1,%d0
737	rts
738
739
740
741div_srcd:
742	bsrl	ckinf_nd
743	bne	fix_stk
744	bfextu	FPTEMP_EX(%a6){#1:#15},%d0	|get dest exp (always pos)
745	bfexts	ETEMP_EX(%a6){#1:#15},%d1	|get src exp (always neg)
746	subl	%d1,%d0			|subtract src from dest
747	cmpl	#0x8000,%d0
748	blt	fix_stk			|if less, not wrap case
749	clrb	WBTEMP_SGN(%a6)
750	movew	ETEMP_EX(%a6),%d0		|find the sign of the result
751	movew	FPTEMP_EX(%a6),%d1
752	eorw	%d1,%d0
753	andiw	#0x8000,%d0
754	beqs	force_ovf
755	st	WBTEMP_SGN(%a6)
756|
757| This code handles the case of the instruction resulting in
758| an overflow condition.
759|
760force_ovf:
761	bclrb	#E1,E_BYTE(%a6)
762	orl	#ovfl_inx_mask,USER_FPSR(%a6)
763	clrw	NMNEXC(%a6)
764	leal	WBTEMP(%a6),%a0		|point a0 to memory location
765	movew	CMDREG1B(%a6),%d0
766	btstl	#6,%d0			|test for forced precision
767	beqs	frcovf_fpcr
768	btstl	#2,%d0			|check for double
769	bnes	frcovf_dbl
770	movel	#0x1,%d0			|inst is forced single
771	bras	frcovf_rnd
772frcovf_dbl:
773	movel	#0x2,%d0			|inst is forced double
774	bras	frcovf_rnd
775frcovf_fpcr:
776	bfextu	FPCR_MODE(%a6){#0:#2},%d0	|inst not forced - use fpcr prec
777frcovf_rnd:
778
779| The 881/882 does not set inex2 for the following case, so the
780| line is commented out to be compatible with 881/882
781|	tst.b	%d0
782|	beq.b	frcovf_x
783|	or.l	#inex2_mask,USER_FPSR(%a6) ;if prec is s or d, set inex2
784
785|frcovf_x:
786	bsrl	ovf_res			|get correct result based on
787|					;round precision/mode.  This
788|					;sets FPSR_CC correctly
789|					;returns in external format
790	bfclr	WBTEMP_SGN(%a6){#0:#8}
791	beq	frcfpn
792	bsetb	#sign_bit,WBTEMP_EX(%a6)
793	bra	frcfpn
794|
795| Inst is fadd.
796|
797wrap_add:
798	cmpb	#0xff,DNRM_FLG(%a6) |if both ops denorm,
799	beq	fix_stk		 |restore to fpu
800|
801| One of the ops is denormalized.  Test for wrap condition
802| and complete the instruction.
803|
804	cmpb	#0x0f,DNRM_FLG(%a6) |check for dest denorm
805	bnes	add_srcd
806add_destd:
807	bsrl	ckinf_ns
808	bne	fix_stk
809	bfextu	ETEMP_EX(%a6){#1:#15},%d0	|get src exp (always pos)
810	bfexts	FPTEMP_EX(%a6){#1:#15},%d1	|get dest exp (always neg)
811	subl	%d1,%d0			|subtract dest from src
812	cmpl	#0x8000,%d0
813	blt	fix_stk			|if less, not wrap case
814	bra	add_wrap
815add_srcd:
816	bsrl	ckinf_nd
817	bne	fix_stk
818	bfextu	FPTEMP_EX(%a6){#1:#15},%d0	|get dest exp (always pos)
819	bfexts	ETEMP_EX(%a6){#1:#15},%d1	|get src exp (always neg)
820	subl	%d1,%d0			|subtract src from dest
821	cmpl	#0x8000,%d0
822	blt	fix_stk			|if less, not wrap case
823|
824| Check the signs of the operands.  If they are unlike, the fpu
825| can be used to add the norm and 1.0 with the sign of the
826| denorm and it will correctly generate the result in extended
827| precision.  We can then call round with no sticky and the result
828| will be correct for the user's rounding mode and precision.  If
829| the signs are the same, we call round with the sticky bit set
830| and the result will be correct for the user's rounding mode and
831| precision.
832|
833add_wrap:
834	movew	ETEMP_EX(%a6),%d0
835	movew	FPTEMP_EX(%a6),%d1
836	eorw	%d1,%d0
837	andiw	#0x8000,%d0
838	beq	add_same
839|
840| The signs are unlike.
841|
842	cmpb	#0x0f,DNRM_FLG(%a6) |is dest the denorm?
843	bnes	add_u_srcd
844	movew	FPTEMP_EX(%a6),%d0
845	andiw	#0x8000,%d0
846	orw	#0x3fff,%d0	|force the exponent to +/- 1
847	movew	%d0,FPTEMP_EX(%a6) |in the denorm
848	movel	USER_FPCR(%a6),%d0
849	andil	#0x30,%d0
850	fmovel	%d0,%fpcr		|set up users rmode and X
851	fmovex	ETEMP(%a6),%fp0
852	faddx	FPTEMP(%a6),%fp0
853	leal	WBTEMP(%a6),%a0	|point a0 to wbtemp in frame
854	fmovel	%fpsr,%d1
855	orl	%d1,USER_FPSR(%a6) |capture cc's and inex from fadd
856	fmovex	%fp0,WBTEMP(%a6)	|write result to memory
857	lsrl	#4,%d0		|put rmode in lower 2 bits
858	movel	USER_FPCR(%a6),%d1
859	andil	#0xc0,%d1
860	lsrl	#6,%d1		|put precision in upper word
861	swap	%d1
862	orl	%d0,%d1		|set up for round call
863	clrl	%d0		|force sticky to zero
864	bclrb	#sign_bit,WBTEMP_EX(%a6)
865	sne	WBTEMP_SGN(%a6)
866	bsrl	round		|round result to users rmode & prec
867	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
868	beq	frcfpnr
869	bsetb	#sign_bit,WBTEMP_EX(%a6)
870	bra	frcfpnr
871add_u_srcd:
872	movew	ETEMP_EX(%a6),%d0
873	andiw	#0x8000,%d0
874	orw	#0x3fff,%d0	|force the exponent to +/- 1
875	movew	%d0,ETEMP_EX(%a6) |in the denorm
876	movel	USER_FPCR(%a6),%d0
877	andil	#0x30,%d0
878	fmovel	%d0,%fpcr		|set up users rmode and X
879	fmovex	ETEMP(%a6),%fp0
880	faddx	FPTEMP(%a6),%fp0
881	fmovel	%fpsr,%d1
882	orl	%d1,USER_FPSR(%a6) |capture cc's and inex from fadd
883	leal	WBTEMP(%a6),%a0	|point a0 to wbtemp in frame
884	fmovex	%fp0,WBTEMP(%a6)	|write result to memory
885	lsrl	#4,%d0		|put rmode in lower 2 bits
886	movel	USER_FPCR(%a6),%d1
887	andil	#0xc0,%d1
888	lsrl	#6,%d1		|put precision in upper word
889	swap	%d1
890	orl	%d0,%d1		|set up for round call
891	clrl	%d0		|force sticky to zero
892	bclrb	#sign_bit,WBTEMP_EX(%a6)
893	sne	WBTEMP_SGN(%a6)	|use internal format for round
894	bsrl	round		|round result to users rmode & prec
895	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
896	beq	frcfpnr
897	bsetb	#sign_bit,WBTEMP_EX(%a6)
898	bra	frcfpnr
899|
900| Signs are alike:
901|
902add_same:
903	cmpb	#0x0f,DNRM_FLG(%a6) |is dest the denorm?
904	bnes	add_s_srcd
905add_s_destd:
906	leal	ETEMP(%a6),%a0
907	movel	USER_FPCR(%a6),%d0
908	andil	#0x30,%d0
909	lsrl	#4,%d0		|put rmode in lower 2 bits
910	movel	USER_FPCR(%a6),%d1
911	andil	#0xc0,%d1
912	lsrl	#6,%d1		|put precision in upper word
913	swap	%d1
914	orl	%d0,%d1		|set up for round call
915	movel	#0x20000000,%d0	|set sticky for round
916	bclrb	#sign_bit,ETEMP_EX(%a6)
917	sne	ETEMP_SGN(%a6)
918	bsrl	round		|round result to users rmode & prec
919	bfclr	ETEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
920	beqs	add_s_dclr
921	bsetb	#sign_bit,ETEMP_EX(%a6)
922add_s_dclr:
923	leal	WBTEMP(%a6),%a0
924	movel	ETEMP(%a6),(%a0)	|write result to wbtemp
925	movel	ETEMP_HI(%a6),4(%a0)
926	movel	ETEMP_LO(%a6),8(%a0)
927	tstw	ETEMP_EX(%a6)
928	bgt	add_ckovf
929	orl	#neg_mask,USER_FPSR(%a6)
930	bra	add_ckovf
931add_s_srcd:
932	leal	FPTEMP(%a6),%a0
933	movel	USER_FPCR(%a6),%d0
934	andil	#0x30,%d0
935	lsrl	#4,%d0		|put rmode in lower 2 bits
936	movel	USER_FPCR(%a6),%d1
937	andil	#0xc0,%d1
938	lsrl	#6,%d1		|put precision in upper word
939	swap	%d1
940	orl	%d0,%d1		|set up for round call
941	movel	#0x20000000,%d0	|set sticky for round
942	bclrb	#sign_bit,FPTEMP_EX(%a6)
943	sne	FPTEMP_SGN(%a6)
944	bsrl	round		|round result to users rmode & prec
945	bfclr	FPTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
946	beqs	add_s_sclr
947	bsetb	#sign_bit,FPTEMP_EX(%a6)
948add_s_sclr:
949	leal	WBTEMP(%a6),%a0
950	movel	FPTEMP(%a6),(%a0)	|write result to wbtemp
951	movel	FPTEMP_HI(%a6),4(%a0)
952	movel	FPTEMP_LO(%a6),8(%a0)
953	tstw	FPTEMP_EX(%a6)
954	bgt	add_ckovf
955	orl	#neg_mask,USER_FPSR(%a6)
956add_ckovf:
957	movew	WBTEMP_EX(%a6),%d0
958	andiw	#0x7fff,%d0
959	cmpiw	#0x7fff,%d0
960	bne	frcfpnr
961|
962| The result has overflowed to $7fff exponent.  Set I, ovfl,
963| and aovfl, and clr the mantissa (incorrectly set by the
964| round routine.)
965|
966	orl	#inf_mask+ovfl_inx_mask,USER_FPSR(%a6)
967	clrl	4(%a0)
968	bra	frcfpnr
969|
970| Inst is fsub.
971|
972wrap_sub:
973	cmpb	#0xff,DNRM_FLG(%a6) |if both ops denorm,
974	beq	fix_stk		 |restore to fpu
975|
976| One of the ops is denormalized.  Test for wrap condition
977| and complete the instruction.
978|
979	cmpb	#0x0f,DNRM_FLG(%a6) |check for dest denorm
980	bnes	sub_srcd
981sub_destd:
982	bsrl	ckinf_ns
983	bne	fix_stk
984	bfextu	ETEMP_EX(%a6){#1:#15},%d0	|get src exp (always pos)
985	bfexts	FPTEMP_EX(%a6){#1:#15},%d1	|get dest exp (always neg)
986	subl	%d1,%d0			|subtract src from dest
987	cmpl	#0x8000,%d0
988	blt	fix_stk			|if less, not wrap case
989	bra	sub_wrap
990sub_srcd:
991	bsrl	ckinf_nd
992	bne	fix_stk
993	bfextu	FPTEMP_EX(%a6){#1:#15},%d0	|get dest exp (always pos)
994	bfexts	ETEMP_EX(%a6){#1:#15},%d1	|get src exp (always neg)
995	subl	%d1,%d0			|subtract dest from src
996	cmpl	#0x8000,%d0
997	blt	fix_stk			|if less, not wrap case
998|
999| Check the signs of the operands.  If they are alike, the fpu
1000| can be used to subtract from the norm 1.0 with the sign of the
1001| denorm and it will correctly generate the result in extended
1002| precision.  We can then call round with no sticky and the result
1003| will be correct for the user's rounding mode and precision.  If
1004| the signs are unlike, we call round with the sticky bit set
1005| and the result will be correct for the user's rounding mode and
1006| precision.
1007|
1008sub_wrap:
1009	movew	ETEMP_EX(%a6),%d0
1010	movew	FPTEMP_EX(%a6),%d1
1011	eorw	%d1,%d0
1012	andiw	#0x8000,%d0
1013	bne	sub_diff
1014|
1015| The signs are alike.
1016|
1017	cmpb	#0x0f,DNRM_FLG(%a6) |is dest the denorm?
1018	bnes	sub_u_srcd
1019	movew	FPTEMP_EX(%a6),%d0
1020	andiw	#0x8000,%d0
1021	orw	#0x3fff,%d0	|force the exponent to +/- 1
1022	movew	%d0,FPTEMP_EX(%a6) |in the denorm
1023	movel	USER_FPCR(%a6),%d0
1024	andil	#0x30,%d0
1025	fmovel	%d0,%fpcr		|set up users rmode and X
1026	fmovex	FPTEMP(%a6),%fp0
1027	fsubx	ETEMP(%a6),%fp0
1028	fmovel	%fpsr,%d1
1029	orl	%d1,USER_FPSR(%a6) |capture cc's and inex from fadd
1030	leal	WBTEMP(%a6),%a0	|point a0 to wbtemp in frame
1031	fmovex	%fp0,WBTEMP(%a6)	|write result to memory
1032	lsrl	#4,%d0		|put rmode in lower 2 bits
1033	movel	USER_FPCR(%a6),%d1
1034	andil	#0xc0,%d1
1035	lsrl	#6,%d1		|put precision in upper word
1036	swap	%d1
1037	orl	%d0,%d1		|set up for round call
1038	clrl	%d0		|force sticky to zero
1039	bclrb	#sign_bit,WBTEMP_EX(%a6)
1040	sne	WBTEMP_SGN(%a6)
1041	bsrl	round		|round result to users rmode & prec
1042	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1043	beq	frcfpnr
1044	bsetb	#sign_bit,WBTEMP_EX(%a6)
1045	bra	frcfpnr
1046sub_u_srcd:
1047	movew	ETEMP_EX(%a6),%d0
1048	andiw	#0x8000,%d0
1049	orw	#0x3fff,%d0	|force the exponent to +/- 1
1050	movew	%d0,ETEMP_EX(%a6) |in the denorm
1051	movel	USER_FPCR(%a6),%d0
1052	andil	#0x30,%d0
1053	fmovel	%d0,%fpcr		|set up users rmode and X
1054	fmovex	FPTEMP(%a6),%fp0
1055	fsubx	ETEMP(%a6),%fp0
1056	fmovel	%fpsr,%d1
1057	orl	%d1,USER_FPSR(%a6) |capture cc's and inex from fadd
1058	leal	WBTEMP(%a6),%a0	|point a0 to wbtemp in frame
1059	fmovex	%fp0,WBTEMP(%a6)	|write result to memory
1060	lsrl	#4,%d0		|put rmode in lower 2 bits
1061	movel	USER_FPCR(%a6),%d1
1062	andil	#0xc0,%d1
1063	lsrl	#6,%d1		|put precision in upper word
1064	swap	%d1
1065	orl	%d0,%d1		|set up for round call
1066	clrl	%d0		|force sticky to zero
1067	bclrb	#sign_bit,WBTEMP_EX(%a6)
1068	sne	WBTEMP_SGN(%a6)
1069	bsrl	round		|round result to users rmode & prec
1070	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1071	beq	frcfpnr
1072	bsetb	#sign_bit,WBTEMP_EX(%a6)
1073	bra	frcfpnr
1074|
1075| Signs are unlike:
1076|
1077sub_diff:
1078	cmpb	#0x0f,DNRM_FLG(%a6) |is dest the denorm?
1079	bnes	sub_s_srcd
1080sub_s_destd:
1081	leal	ETEMP(%a6),%a0
1082	movel	USER_FPCR(%a6),%d0
1083	andil	#0x30,%d0
1084	lsrl	#4,%d0		|put rmode in lower 2 bits
1085	movel	USER_FPCR(%a6),%d1
1086	andil	#0xc0,%d1
1087	lsrl	#6,%d1		|put precision in upper word
1088	swap	%d1
1089	orl	%d0,%d1		|set up for round call
1090	movel	#0x20000000,%d0	|set sticky for round
1091|
1092| Since the dest is the denorm, the sign is the opposite of the
1093| norm sign.
1094|
1095	eoriw	#0x8000,ETEMP_EX(%a6)	|flip sign on result
1096	tstw	ETEMP_EX(%a6)
1097	bgts	sub_s_dwr
1098	orl	#neg_mask,USER_FPSR(%a6)
1099sub_s_dwr:
1100	bclrb	#sign_bit,ETEMP_EX(%a6)
1101	sne	ETEMP_SGN(%a6)
1102	bsrl	round		|round result to users rmode & prec
1103	bfclr	ETEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1104	beqs	sub_s_dclr
1105	bsetb	#sign_bit,ETEMP_EX(%a6)
1106sub_s_dclr:
1107	leal	WBTEMP(%a6),%a0
1108	movel	ETEMP(%a6),(%a0)	|write result to wbtemp
1109	movel	ETEMP_HI(%a6),4(%a0)
1110	movel	ETEMP_LO(%a6),8(%a0)
1111	bra	sub_ckovf
1112sub_s_srcd:
1113	leal	FPTEMP(%a6),%a0
1114	movel	USER_FPCR(%a6),%d0
1115	andil	#0x30,%d0
1116	lsrl	#4,%d0		|put rmode in lower 2 bits
1117	movel	USER_FPCR(%a6),%d1
1118	andil	#0xc0,%d1
1119	lsrl	#6,%d1		|put precision in upper word
1120	swap	%d1
1121	orl	%d0,%d1		|set up for round call
1122	movel	#0x20000000,%d0	|set sticky for round
1123	bclrb	#sign_bit,FPTEMP_EX(%a6)
1124	sne	FPTEMP_SGN(%a6)
1125	bsrl	round		|round result to users rmode & prec
1126	bfclr	FPTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1127	beqs	sub_s_sclr
1128	bsetb	#sign_bit,FPTEMP_EX(%a6)
1129sub_s_sclr:
1130	leal	WBTEMP(%a6),%a0
1131	movel	FPTEMP(%a6),(%a0)	|write result to wbtemp
1132	movel	FPTEMP_HI(%a6),4(%a0)
1133	movel	FPTEMP_LO(%a6),8(%a0)
1134	tstw	FPTEMP_EX(%a6)
1135	bgt	sub_ckovf
1136	orl	#neg_mask,USER_FPSR(%a6)
1137sub_ckovf:
1138	movew	WBTEMP_EX(%a6),%d0
1139	andiw	#0x7fff,%d0
1140	cmpiw	#0x7fff,%d0
1141	bne	frcfpnr
1142|
1143| The result has overflowed to $7fff exponent.  Set I, ovfl,
1144| and aovfl, and clr the mantissa (incorrectly set by the
1145| round routine.)
1146|
1147	orl	#inf_mask+ovfl_inx_mask,USER_FPSR(%a6)
1148	clrl	4(%a0)
1149	bra	frcfpnr
1150|
1151| Inst is fcmp.
1152|
1153wrap_cmp:
1154	cmpb	#0xff,DNRM_FLG(%a6) |if both ops denorm,
1155	beq	fix_stk		 |restore to fpu
1156|
1157| One of the ops is denormalized.  Test for wrap condition
1158| and complete the instruction.
1159|
1160	cmpb	#0x0f,DNRM_FLG(%a6) |check for dest denorm
1161	bnes	cmp_srcd
1162cmp_destd:
1163	bsrl	ckinf_ns
1164	bne	fix_stk
1165	bfextu	ETEMP_EX(%a6){#1:#15},%d0	|get src exp (always pos)
1166	bfexts	FPTEMP_EX(%a6){#1:#15},%d1	|get dest exp (always neg)
1167	subl	%d1,%d0			|subtract dest from src
1168	cmpl	#0x8000,%d0
1169	blt	fix_stk			|if less, not wrap case
1170	tstw	ETEMP_EX(%a6)		|set N to ~sign_of(src)
1171	bge	cmp_setn
1172	rts
1173cmp_srcd:
1174	bsrl	ckinf_nd
1175	bne	fix_stk
1176	bfextu	FPTEMP_EX(%a6){#1:#15},%d0	|get dest exp (always pos)
1177	bfexts	ETEMP_EX(%a6){#1:#15},%d1	|get src exp (always neg)
1178	subl	%d1,%d0			|subtract src from dest
1179	cmpl	#0x8000,%d0
1180	blt	fix_stk			|if less, not wrap case
1181	tstw	FPTEMP_EX(%a6)		|set N to sign_of(dest)
1182	blt	cmp_setn
1183	rts
1184cmp_setn:
1185	orl	#neg_mask,USER_FPSR(%a6)
1186	rts
1187
1188|
1189| Inst is fmul.
1190|
1191wrap_mul:
1192	cmpb	#0xff,DNRM_FLG(%a6) |if both ops denorm,
1193	beq	force_unf	|force an underflow (really!)
1194|
1195| One of the ops is denormalized.  Test for wrap condition
1196| and complete the instruction.
1197|
1198	cmpb	#0x0f,DNRM_FLG(%a6) |check for dest denorm
1199	bnes	mul_srcd
1200mul_destd:
1201	bsrl	ckinf_ns
1202	bne	fix_stk
1203	bfextu	ETEMP_EX(%a6){#1:#15},%d0	|get src exp (always pos)
1204	bfexts	FPTEMP_EX(%a6){#1:#15},%d1	|get dest exp (always neg)
1205	addl	%d1,%d0			|subtract dest from src
1206	bgt	fix_stk
1207	bra	force_unf
1208mul_srcd:
1209	bsrl	ckinf_nd
1210	bne	fix_stk
1211	bfextu	FPTEMP_EX(%a6){#1:#15},%d0	|get dest exp (always pos)
1212	bfexts	ETEMP_EX(%a6){#1:#15},%d1	|get src exp (always neg)
1213	addl	%d1,%d0			|subtract src from dest
1214	bgt	fix_stk
1215
1216|
1217| This code handles the case of the instruction resulting in
1218| an underflow condition.
1219|
1220force_unf:
1221	bclrb	#E1,E_BYTE(%a6)
1222	orl	#unfinx_mask,USER_FPSR(%a6)
1223	clrw	NMNEXC(%a6)
1224	clrb	WBTEMP_SGN(%a6)
1225	movew	ETEMP_EX(%a6),%d0		|find the sign of the result
1226	movew	FPTEMP_EX(%a6),%d1
1227	eorw	%d1,%d0
1228	andiw	#0x8000,%d0
1229	beqs	frcunfcont
1230	st	WBTEMP_SGN(%a6)
1231frcunfcont:
1232	lea	WBTEMP(%a6),%a0		|point a0 to memory location
1233	movew	CMDREG1B(%a6),%d0
1234	btstl	#6,%d0			|test for forced precision
1235	beqs	frcunf_fpcr
1236	btstl	#2,%d0			|check for double
1237	bnes	frcunf_dbl
1238	movel	#0x1,%d0			|inst is forced single
1239	bras	frcunf_rnd
1240frcunf_dbl:
1241	movel	#0x2,%d0			|inst is forced double
1242	bras	frcunf_rnd
1243frcunf_fpcr:
1244	bfextu	FPCR_MODE(%a6){#0:#2},%d0	|inst not forced - use fpcr prec
1245frcunf_rnd:
1246	bsrl	unf_sub			|get correct result based on
1247|					;round precision/mode.  This
1248|					;sets FPSR_CC correctly
1249	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1250	beqs	frcfpn
1251	bsetb	#sign_bit,WBTEMP_EX(%a6)
1252	bra	frcfpn
1253
1254|
1255| Write the result to the user's fpn.  All results must be HUGE to be
1256| written; otherwise the results would have overflowed or underflowed.
1257| If the rounding precision is single or double, the ovf_res routine
1258| is needed to correctly supply the max value.
1259|
1260frcfpnr:
1261	movew	CMDREG1B(%a6),%d0
1262	btstl	#6,%d0			|test for forced precision
1263	beqs	frcfpn_fpcr
1264	btstl	#2,%d0			|check for double
1265	bnes	frcfpn_dbl
1266	movel	#0x1,%d0			|inst is forced single
1267	bras	frcfpn_rnd
1268frcfpn_dbl:
1269	movel	#0x2,%d0			|inst is forced double
1270	bras	frcfpn_rnd
1271frcfpn_fpcr:
1272	bfextu	FPCR_MODE(%a6){#0:#2},%d0	|inst not forced - use fpcr prec
1273	tstb	%d0
1274	beqs	frcfpn			|if extended, write what you got
1275frcfpn_rnd:
1276	bclrb	#sign_bit,WBTEMP_EX(%a6)
1277	sne	WBTEMP_SGN(%a6)
1278	bsrl	ovf_res			|get correct result based on
1279|					;round precision/mode.  This
1280|					;sets FPSR_CC correctly
1281	bfclr	WBTEMP_SGN(%a6){#0:#8}	|convert back to IEEE ext format
1282	beqs	frcfpn_clr
1283	bsetb	#sign_bit,WBTEMP_EX(%a6)
1284frcfpn_clr:
1285	orl	#ovfinx_mask,USER_FPSR(%a6)
1286|
1287| Perform the write.
1288|
1289frcfpn:
1290	bfextu	CMDREG1B(%a6){#6:#3},%d0	|extract fp destination register
1291	cmpib	#3,%d0
1292	bles	frc0123			|check if dest is fp0-fp3
1293	movel	#7,%d1
1294	subl	%d0,%d1
1295	clrl	%d0
1296	bsetl	%d1,%d0
1297	fmovemx WBTEMP(%a6),%d0
1298	rts
1299frc0123:
1300	cmpib	#0,%d0
1301	beqs	frc0_dst
1302	cmpib	#1,%d0
1303	beqs	frc1_dst
1304	cmpib	#2,%d0
1305	beqs	frc2_dst
1306frc3_dst:
1307	movel	WBTEMP_EX(%a6),USER_FP3(%a6)
1308	movel	WBTEMP_HI(%a6),USER_FP3+4(%a6)
1309	movel	WBTEMP_LO(%a6),USER_FP3+8(%a6)
1310	rts
1311frc2_dst:
1312	movel	WBTEMP_EX(%a6),USER_FP2(%a6)
1313	movel	WBTEMP_HI(%a6),USER_FP2+4(%a6)
1314	movel	WBTEMP_LO(%a6),USER_FP2+8(%a6)
1315	rts
1316frc1_dst:
1317	movel	WBTEMP_EX(%a6),USER_FP1(%a6)
1318	movel	WBTEMP_HI(%a6),USER_FP1+4(%a6)
1319	movel	WBTEMP_LO(%a6),USER_FP1+8(%a6)
1320	rts
1321frc0_dst:
1322	movel	WBTEMP_EX(%a6),USER_FP0(%a6)
1323	movel	WBTEMP_HI(%a6),USER_FP0+4(%a6)
1324	movel	WBTEMP_LO(%a6),USER_FP0+8(%a6)
1325	rts
1326
1327|
1328| Write etemp to fpn.
1329| A check is made on enabled and signalled snan exceptions,
1330| and the destination is not overwritten if this condition exists.
1331| This code is designed to make fmoveins of unsupported data types
1332| faster.
1333|
1334wr_etemp:
1335	btstb	#snan_bit,FPSR_EXCEPT(%a6)	|if snan is set, and
1336	beqs	fmoveinc		|enabled, force restore
1337	btstb	#snan_bit,FPCR_ENABLE(%a6) |and don't overwrite
1338	beqs	fmoveinc		|the dest
1339	movel	ETEMP_EX(%a6),FPTEMP_EX(%a6)	|set up fptemp sign for
1340|						;snan handler
1341	tstb	ETEMP(%a6)		|check for negative
1342	blts	snan_neg
1343	rts
1344snan_neg:
1345	orl	#neg_bit,USER_FPSR(%a6)	|snan is negative; set N
1346	rts
1347fmoveinc:
1348	clrw	NMNEXC(%a6)
1349	bclrb	#E1,E_BYTE(%a6)
1350	moveb	STAG(%a6),%d0		|check if stag is inf
1351	andib	#0xe0,%d0
1352	cmpib	#0x40,%d0
1353	bnes	fminc_cnan
1354	orl	#inf_mask,USER_FPSR(%a6) |if inf, nothing yet has set I
1355	tstw	LOCAL_EX(%a0)		|check sign
1356	bges	fminc_con
1357	orl	#neg_mask,USER_FPSR(%a6)
1358	bra	fminc_con
1359fminc_cnan:
1360	cmpib	#0x60,%d0			|check if stag is NaN
1361	bnes	fminc_czero
1362	orl	#nan_mask,USER_FPSR(%a6) |if nan, nothing yet has set NaN
1363	movel	ETEMP_EX(%a6),FPTEMP_EX(%a6)	|set up fptemp sign for
1364|						;snan handler
1365	tstw	LOCAL_EX(%a0)		|check sign
1366	bges	fminc_con
1367	orl	#neg_mask,USER_FPSR(%a6)
1368	bra	fminc_con
1369fminc_czero:
1370	cmpib	#0x20,%d0			|check if zero
1371	bnes	fminc_con
1372	orl	#z_mask,USER_FPSR(%a6)	|if zero, set Z
1373	tstw	LOCAL_EX(%a0)		|check sign
1374	bges	fminc_con
1375	orl	#neg_mask,USER_FPSR(%a6)
1376fminc_con:
1377	bfextu	CMDREG1B(%a6){#6:#3},%d0	|extract fp destination register
1378	cmpib	#3,%d0
1379	bles	fp0123			|check if dest is fp0-fp3
1380	movel	#7,%d1
1381	subl	%d0,%d1
1382	clrl	%d0
1383	bsetl	%d1,%d0
1384	fmovemx ETEMP(%a6),%d0
1385	rts
1386
1387fp0123:
1388	cmpib	#0,%d0
1389	beqs	fp0_dst
1390	cmpib	#1,%d0
1391	beqs	fp1_dst
1392	cmpib	#2,%d0
1393	beqs	fp2_dst
1394fp3_dst:
1395	movel	ETEMP_EX(%a6),USER_FP3(%a6)
1396	movel	ETEMP_HI(%a6),USER_FP3+4(%a6)
1397	movel	ETEMP_LO(%a6),USER_FP3+8(%a6)
1398	rts
1399fp2_dst:
1400	movel	ETEMP_EX(%a6),USER_FP2(%a6)
1401	movel	ETEMP_HI(%a6),USER_FP2+4(%a6)
1402	movel	ETEMP_LO(%a6),USER_FP2+8(%a6)
1403	rts
1404fp1_dst:
1405	movel	ETEMP_EX(%a6),USER_FP1(%a6)
1406	movel	ETEMP_HI(%a6),USER_FP1+4(%a6)
1407	movel	ETEMP_LO(%a6),USER_FP1+8(%a6)
1408	rts
1409fp0_dst:
1410	movel	ETEMP_EX(%a6),USER_FP0(%a6)
1411	movel	ETEMP_HI(%a6),USER_FP0+4(%a6)
1412	movel	ETEMP_LO(%a6),USER_FP0+8(%a6)
1413	rts
1414
1415opclass3:
1416	st	CU_ONLY(%a6)
1417	movew	CMDREG1B(%a6),%d0	|check if packed moveout
1418	andiw	#0x0c00,%d0	|isolate last 2 bits of size field
1419	cmpiw	#0x0c00,%d0	|if size is 011 or 111, it is packed
1420	beq	pack_out	|else it is norm or denorm
1421	bra	mv_out
1422
1423
1424|
1425|	MOVE OUT
1426|
1427
1428mv_tbl:
1429	.long	li
1430	.long	sgp
1431	.long	xp
1432	.long	mvout_end	|should never be taken
1433	.long	wi
1434	.long	dp
1435	.long	bi
1436	.long	mvout_end	|should never be taken
1437mv_out:
1438	bfextu	CMDREG1B(%a6){#3:#3},%d1	|put source specifier in d1
1439	leal	mv_tbl,%a0
1440	movel	%a0@(%d1:l:4),%a0
1441	jmp	(%a0)
1442
1443|
1444| This exit is for move-out to memory.  The aunfl bit is
1445| set if the result is inex and unfl is signalled.
1446|
1447mvout_end:
1448	btstb	#inex2_bit,FPSR_EXCEPT(%a6)
1449	beqs	no_aufl
1450	btstb	#unfl_bit,FPSR_EXCEPT(%a6)
1451	beqs	no_aufl
1452	bsetb	#aunfl_bit,FPSR_AEXCEPT(%a6)
1453no_aufl:
1454	clrw	NMNEXC(%a6)
1455	bclrb	#E1,E_BYTE(%a6)
1456	fmovel	#0,%FPSR			|clear any cc bits from res_func
1457|
1458| Return ETEMP to extended format from internal extended format so
1459| that gen_except will have a correctly signed value for ovfl/unfl
1460| handlers.
1461|
1462	bfclr	ETEMP_SGN(%a6){#0:#8}
1463	beqs	mvout_con
1464	bsetb	#sign_bit,ETEMP_EX(%a6)
1465mvout_con:
1466	rts
1467|
1468| This exit is for move-out to int register.  The aunfl bit is
1469| not set in any case for this move.
1470|
1471mvouti_end:
1472	clrw	NMNEXC(%a6)
1473	bclrb	#E1,E_BYTE(%a6)
1474	fmovel	#0,%FPSR			|clear any cc bits from res_func
1475|
1476| Return ETEMP to extended format from internal extended format so
1477| that gen_except will have a correctly signed value for ovfl/unfl
1478| handlers.
1479|
1480	bfclr	ETEMP_SGN(%a6){#0:#8}
1481	beqs	mvouti_con
1482	bsetb	#sign_bit,ETEMP_EX(%a6)
1483mvouti_con:
1484	rts
1485|
1486| li is used to handle a long integer source specifier
1487|
1488
1489li:
1490	moveql	#4,%d0		|set byte count
1491
1492	btstb	#7,STAG(%a6)	|check for extended denorm
1493	bne	int_dnrm	|if so, branch
1494
1495	fmovemx ETEMP(%a6),%fp0-%fp0
1496	fcmpd	#0x41dfffffffc00000,%fp0
1497| 41dfffffffc00000 in dbl prec = 401d0000fffffffe00000000 in ext prec
1498	fbge	lo_plrg
1499	fcmpd	#0xc1e0000000000000,%fp0
1500| c1e0000000000000 in dbl prec = c01e00008000000000000000 in ext prec
1501	fble	lo_nlrg
1502|
1503| at this point, the answer is between the largest pos and neg values
1504|
1505	movel	USER_FPCR(%a6),%d1	|use user's rounding mode
1506	andil	#0x30,%d1
1507	fmovel	%d1,%fpcr
1508	fmovel	%fp0,L_SCR1(%a6)	|let the 040 perform conversion
1509	fmovel %fpsr,%d1
1510	orl	%d1,USER_FPSR(%a6)	|capture inex2/ainex if set
1511	bra	int_wrt
1512
1513
1514lo_plrg:
1515	movel	#0x7fffffff,L_SCR1(%a6)	|answer is largest positive int
1516	fbeq	int_wrt			|exact answer
1517	fcmpd	#0x41dfffffffe00000,%fp0
1518| 41dfffffffe00000 in dbl prec = 401d0000ffffffff00000000 in ext prec
1519	fbge	int_operr		|set operr
1520	bra	int_inx			|set inexact
1521
1522lo_nlrg:
1523	movel	#0x80000000,L_SCR1(%a6)
1524	fbeq	int_wrt			|exact answer
1525	fcmpd	#0xc1e0000000100000,%fp0
1526| c1e0000000100000 in dbl prec = c01e00008000000080000000 in ext prec
1527	fblt	int_operr		|set operr
1528	bra	int_inx			|set inexact
1529
1530|
1531| wi is used to handle a word integer source specifier
1532|
1533
1534wi:
1535	moveql	#2,%d0		|set byte count
1536
1537	btstb	#7,STAG(%a6)	|check for extended denorm
1538	bne	int_dnrm	|branch if so
1539
1540	fmovemx ETEMP(%a6),%fp0-%fp0
1541	fcmps	#0x46fffe00,%fp0
1542| 46fffe00 in sgl prec = 400d0000fffe000000000000 in ext prec
1543	fbge	wo_plrg
1544	fcmps	#0xc7000000,%fp0
1545| c7000000 in sgl prec = c00e00008000000000000000 in ext prec
1546	fble	wo_nlrg
1547
1548|
1549| at this point, the answer is between the largest pos and neg values
1550|
1551	movel	USER_FPCR(%a6),%d1	|use user's rounding mode
1552	andil	#0x30,%d1
1553	fmovel	%d1,%fpcr
1554	fmovew	%fp0,L_SCR1(%a6)	|let the 040 perform conversion
1555	fmovel %fpsr,%d1
1556	orl	%d1,USER_FPSR(%a6)	|capture inex2/ainex if set
1557	bra	int_wrt
1558
1559wo_plrg:
1560	movew	#0x7fff,L_SCR1(%a6)	|answer is largest positive int
1561	fbeq	int_wrt			|exact answer
1562	fcmps	#0x46ffff00,%fp0
1563| 46ffff00 in sgl prec = 400d0000ffff000000000000 in ext prec
1564	fbge	int_operr		|set operr
1565	bra	int_inx			|set inexact
1566
1567wo_nlrg:
1568	movew	#0x8000,L_SCR1(%a6)
1569	fbeq	int_wrt			|exact answer
1570	fcmps	#0xc7000080,%fp0
1571| c7000080 in sgl prec = c00e00008000800000000000 in ext prec
1572	fblt	int_operr		|set operr
1573	bra	int_inx			|set inexact
1574
1575|
1576| bi is used to handle a byte integer source specifier
1577|
1578
1579bi:
1580	moveql	#1,%d0		|set byte count
1581
1582	btstb	#7,STAG(%a6)	|check for extended denorm
1583	bne	int_dnrm	|branch if so
1584
1585	fmovemx ETEMP(%a6),%fp0-%fp0
1586	fcmps	#0x42fe0000,%fp0
1587| 42fe0000 in sgl prec = 40050000fe00000000000000 in ext prec
1588	fbge	by_plrg
1589	fcmps	#0xc3000000,%fp0
1590| c3000000 in sgl prec = c00600008000000000000000 in ext prec
1591	fble	by_nlrg
1592
1593|
1594| at this point, the answer is between the largest pos and neg values
1595|
1596	movel	USER_FPCR(%a6),%d1	|use user's rounding mode
1597	andil	#0x30,%d1
1598	fmovel	%d1,%fpcr
1599	fmoveb	%fp0,L_SCR1(%a6)	|let the 040 perform conversion
1600	fmovel %fpsr,%d1
1601	orl	%d1,USER_FPSR(%a6)	|capture inex2/ainex if set
1602	bra	int_wrt
1603
1604by_plrg:
1605	moveb	#0x7f,L_SCR1(%a6)		|answer is largest positive int
1606	fbeq	int_wrt			|exact answer
1607	fcmps	#0x42ff0000,%fp0
1608| 42ff0000 in sgl prec = 40050000ff00000000000000 in ext prec
1609	fbge	int_operr		|set operr
1610	bra	int_inx			|set inexact
1611
1612by_nlrg:
1613	moveb	#0x80,L_SCR1(%a6)
1614	fbeq	int_wrt			|exact answer
1615	fcmps	#0xc3008000,%fp0
1616| c3008000 in sgl prec = c00600008080000000000000 in ext prec
1617	fblt	int_operr		|set operr
1618	bra	int_inx			|set inexact
1619
1620|
1621| Common integer routines
1622|
1623| int_drnrm---account for possible nonzero result for round up with positive
1624| operand and round down for negative answer.  In the first case (result = 1)
1625| byte-width (store in d0) of result must be honored.  In the second case,
1626| -1 in L_SCR1(a6) will cover all contingencies (FMOVE.B/W/L out).
1627
1628int_dnrm:
1629	movel	#0,L_SCR1(%a6)	| initialize result to 0
1630	bfextu	FPCR_MODE(%a6){#2:#2},%d1	| d1 is the rounding mode
1631	cmpb	#2,%d1
1632	bmis	int_inx		| if RN or RZ, done
1633	bnes	int_rp		| if RP, continue below
1634	tstw	ETEMP(%a6)	| RM: store -1 in L_SCR1 if src is negative
1635	bpls	int_inx		| otherwise result is 0
1636	movel	#-1,L_SCR1(%a6)
1637	bras	int_inx
1638int_rp:
1639	tstw	ETEMP(%a6)	| RP: store +1 of proper width in L_SCR1 if
1640|				; source is greater than 0
1641	bmis	int_inx		| otherwise, result is 0
1642	lea	L_SCR1(%a6),%a1	| a1 is address of L_SCR1
1643	addal	%d0,%a1		| offset by destination width -1
1644	subal	#1,%a1
1645	bsetb	#0,(%a1)		| set low bit at a1 address
1646int_inx:
1647	oril	#inx2a_mask,USER_FPSR(%a6)
1648	bras	int_wrt
1649int_operr:
1650	fmovemx %fp0-%fp0,FPTEMP(%a6)	|FPTEMP must contain the extended
1651|				;precision source that needs to be
1652|				;converted to integer this is required
1653|				;if the operr exception is enabled.
1654|				;set operr/aiop (no inex2 on int ovfl)
1655
1656	oril	#opaop_mask,USER_FPSR(%a6)
1657|				;fall through to perform int_wrt
1658int_wrt:
1659	movel	EXC_EA(%a6),%a1	|load destination address
1660	tstl	%a1		|check to see if it is a dest register
1661	beqs	wrt_dn		|write data register
1662	lea	L_SCR1(%a6),%a0	|point to supervisor source address
1663	bsrl	mem_write
1664	bra	mvouti_end
1665
1666wrt_dn:
1667	movel	%d0,-(%sp)	|d0 currently contains the size to write
1668	bsrl	get_fline	|get_fline returns Dn in d0
1669	andiw	#0x7,%d0		|isolate register
1670	movel	(%sp)+,%d1	|get size
1671	cmpil	#4,%d1		|most frequent case
1672	beqs	sz_long
1673	cmpil	#2,%d1
1674	bnes	sz_con
1675	orl	#8,%d0		|add 'word' size to register#
1676	bras	sz_con
1677sz_long:
1678	orl	#0x10,%d0		|add 'long' size to register#
1679sz_con:
1680	movel	%d0,%d1		|reg_dest expects size:reg in d1
1681	bsrl	reg_dest	|load proper data register
1682	bra	mvouti_end
1683xp:
1684	lea	ETEMP(%a6),%a0
1685	bclrb	#sign_bit,LOCAL_EX(%a0)
1686	sne	LOCAL_SGN(%a0)
1687	btstb	#7,STAG(%a6)	|check for extended denorm
1688	bne	xdnrm
1689	clrl	%d0
1690	bras	do_fp		|do normal case
1691sgp:
1692	lea	ETEMP(%a6),%a0
1693	bclrb	#sign_bit,LOCAL_EX(%a0)
1694	sne	LOCAL_SGN(%a0)
1695	btstb	#7,STAG(%a6)	|check for extended denorm
1696	bne	sp_catas	|branch if so
1697	movew	LOCAL_EX(%a0),%d0
1698	lea	sp_bnds,%a1
1699	cmpw	(%a1),%d0
1700	blt	sp_under
1701	cmpw	2(%a1),%d0
1702	bgt	sp_over
1703	movel	#1,%d0		|set destination format to single
1704	bras	do_fp		|do normal case
1705dp:
1706	lea	ETEMP(%a6),%a0
1707	bclrb	#sign_bit,LOCAL_EX(%a0)
1708	sne	LOCAL_SGN(%a0)
1709
1710	btstb	#7,STAG(%a6)	|check for extended denorm
1711	bne	dp_catas	|branch if so
1712
1713	movew	LOCAL_EX(%a0),%d0
1714	lea	dp_bnds,%a1
1715
1716	cmpw	(%a1),%d0
1717	blt	dp_under
1718	cmpw	2(%a1),%d0
1719	bgt	dp_over
1720
1721	movel	#2,%d0		|set destination format to double
1722|				;fall through to do_fp
1723|
1724do_fp:
1725	bfextu	FPCR_MODE(%a6){#2:#2},%d1	|rnd mode in d1
1726	swap	%d0			|rnd prec in upper word
1727	addl	%d0,%d1			|d1 has PREC/MODE info
1728
1729	clrl	%d0			|clear g,r,s
1730
1731	bsrl	round			|round
1732
1733	movel	%a0,%a1
1734	movel	EXC_EA(%a6),%a0
1735
1736	bfextu	CMDREG1B(%a6){#3:#3},%d1	|extract destination format
1737|					;at this point only the dest
1738|					;formats sgl, dbl, ext are
1739|					;possible
1740	cmpb	#2,%d1
1741	bgts	ddbl			|double=5, extended=2, single=1
1742	bnes	dsgl
1743|					;fall through to dext
1744dext:
1745	bsrl	dest_ext
1746	bra	mvout_end
1747dsgl:
1748	bsrl	dest_sgl
1749	bra	mvout_end
1750ddbl:
1751	bsrl	dest_dbl
1752	bra	mvout_end
1753
1754|
1755| Handle possible denorm or catastrophic underflow cases here
1756|
1757xdnrm:
1758	bsr	set_xop		|initialize WBTEMP
1759	bsetb	#wbtemp15_bit,WB_BYTE(%a6) |set wbtemp15
1760
1761	movel	%a0,%a1
1762	movel	EXC_EA(%a6),%a0	|a0 has the destination pointer
1763	bsrl	dest_ext	|store to memory
1764	bsetb	#unfl_bit,FPSR_EXCEPT(%a6)
1765	bra	mvout_end
1766
1767sp_under:
1768	bsetb	#etemp15_bit,STAG(%a6)
1769
1770	cmpw	4(%a1),%d0
1771	blts	sp_catas	|catastrophic underflow case
1772
1773	movel	#1,%d0		|load in round precision
1774	movel	#sgl_thresh,%d1	|load in single denorm threshold
1775	bsrl	dpspdnrm	|expects d1 to have the proper
1776|				;denorm threshold
1777	bsrl	dest_sgl	|stores value to destination
1778	bsetb	#unfl_bit,FPSR_EXCEPT(%a6)
1779	bra	mvout_end	|exit
1780
1781dp_under:
1782	bsetb	#etemp15_bit,STAG(%a6)
1783
1784	cmpw	4(%a1),%d0
1785	blts	dp_catas	|catastrophic underflow case
1786
1787	movel	#dbl_thresh,%d1	|load in double precision threshold
1788	movel	#2,%d0
1789	bsrl	dpspdnrm	|expects d1 to have proper
1790|				;denorm threshold
1791|				;expects d0 to have round precision
1792	bsrl	dest_dbl	|store value to destination
1793	bsetb	#unfl_bit,FPSR_EXCEPT(%a6)
1794	bra	mvout_end	|exit
1795
1796|
1797| Handle catastrophic underflow cases here
1798|
1799sp_catas:
1800| Temp fix for z bit set in unf_sub
1801	movel	USER_FPSR(%a6),-(%a7)
1802
1803	movel	#1,%d0		|set round precision to sgl
1804
1805	bsrl	unf_sub		|a0 points to result
1806
1807	movel	(%a7)+,USER_FPSR(%a6)
1808
1809	movel	#1,%d0
1810	subw	%d0,LOCAL_EX(%a0) |account for difference between
1811|				;denorm/norm bias
1812
1813	movel	%a0,%a1		|a1 has the operand input
1814	movel	EXC_EA(%a6),%a0	|a0 has the destination pointer
1815
1816	bsrl	dest_sgl	|store the result
1817	oril	#unfinx_mask,USER_FPSR(%a6)
1818	bra	mvout_end
1819
1820dp_catas:
1821| Temp fix for z bit set in unf_sub
1822	movel	USER_FPSR(%a6),-(%a7)
1823
1824	movel	#2,%d0		|set round precision to dbl
1825	bsrl	unf_sub		|a0 points to result
1826
1827	movel	(%a7)+,USER_FPSR(%a6)
1828
1829	movel	#1,%d0
1830	subw	%d0,LOCAL_EX(%a0) |account for difference between
1831|				;denorm/norm bias
1832
1833	movel	%a0,%a1		|a1 has the operand input
1834	movel	EXC_EA(%a6),%a0	|a0 has the destination pointer
1835
1836	bsrl	dest_dbl	|store the result
1837	oril	#unfinx_mask,USER_FPSR(%a6)
1838	bra	mvout_end
1839
1840|
1841| Handle catastrophic overflow cases here
1842|
1843sp_over:
1844| Temp fix for z bit set in unf_sub
1845	movel	USER_FPSR(%a6),-(%a7)
1846
1847	movel	#1,%d0
1848	leal	FP_SCR1(%a6),%a0	|use FP_SCR1 for creating result
1849	movel	ETEMP_EX(%a6),(%a0)
1850	movel	ETEMP_HI(%a6),4(%a0)
1851	movel	ETEMP_LO(%a6),8(%a0)
1852	bsrl	ovf_res
1853
1854	movel	(%a7)+,USER_FPSR(%a6)
1855
1856	movel	%a0,%a1
1857	movel	EXC_EA(%a6),%a0
1858	bsrl	dest_sgl
1859	orl	#ovfinx_mask,USER_FPSR(%a6)
1860	bra	mvout_end
1861
1862dp_over:
1863| Temp fix for z bit set in ovf_res
1864	movel	USER_FPSR(%a6),-(%a7)
1865
1866	movel	#2,%d0
1867	leal	FP_SCR1(%a6),%a0	|use FP_SCR1 for creating result
1868	movel	ETEMP_EX(%a6),(%a0)
1869	movel	ETEMP_HI(%a6),4(%a0)
1870	movel	ETEMP_LO(%a6),8(%a0)
1871	bsrl	ovf_res
1872
1873	movel	(%a7)+,USER_FPSR(%a6)
1874
1875	movel	%a0,%a1
1876	movel	EXC_EA(%a6),%a0
1877	bsrl	dest_dbl
1878	orl	#ovfinx_mask,USER_FPSR(%a6)
1879	bra	mvout_end
1880
1881|
1882|	DPSPDNRM
1883|
1884| This subroutine takes an extended normalized number and denormalizes
1885| it to the given round precision. This subroutine also decrements
1886| the input operand's exponent by 1 to account for the fact that
1887| dest_sgl or dest_dbl expects a normalized number's bias.
1888|
1889| Input: a0  points to a normalized number in internal extended format
1890|	 d0  is the round precision (=1 for sgl; =2 for dbl)
1891|	 d1  is the single precision or double precision
1892|	     denorm threshold
1893|
1894| Output: (In the format for dest_sgl or dest_dbl)
1895|	 a0   points to the destination
1896|	 a1   points to the operand
1897|
1898| Exceptions: Reports inexact 2 exception by setting USER_FPSR bits
1899|
1900dpspdnrm:
1901	movel	%d0,-(%a7)	|save round precision
1902	clrl	%d0		|clear initial g,r,s
1903	bsrl	dnrm_lp		|careful with d0, it's needed by round
1904
1905	bfextu	FPCR_MODE(%a6){#2:#2},%d1 |get rounding mode
1906	swap	%d1
1907	movew	2(%a7),%d1	|set rounding precision
1908	swap	%d1		|at this point d1 has PREC/MODE info
1909	bsrl	round		|round result, sets the inex bit in
1910|				;USER_FPSR if needed
1911
1912	movew	#1,%d0
1913	subw	%d0,LOCAL_EX(%a0) |account for difference in denorm
1914|				;vs norm bias
1915
1916	movel	%a0,%a1		|a1 has the operand input
1917	movel	EXC_EA(%a6),%a0	|a0 has the destination pointer
1918	addw	#4,%a7		|pop stack
1919	rts
1920|
1921| SET_XOP initialized WBTEMP with the value pointed to by a0
1922| input: a0 points to input operand in the internal extended format
1923|
1924set_xop:
1925	movel	LOCAL_EX(%a0),WBTEMP_EX(%a6)
1926	movel	LOCAL_HI(%a0),WBTEMP_HI(%a6)
1927	movel	LOCAL_LO(%a0),WBTEMP_LO(%a6)
1928	bfclr	WBTEMP_SGN(%a6){#0:#8}
1929	beqs	sxop
1930	bsetb	#sign_bit,WBTEMP_EX(%a6)
1931sxop:
1932	bfclr	STAG(%a6){#5:#4}	|clear wbtm66,wbtm1,wbtm0,sbit
1933	rts
1934|
1935|	P_MOVE
1936|
1937p_movet:
1938	.long	p_move
1939	.long	p_movez
1940	.long	p_movei
1941	.long	p_moven
1942	.long	p_move
1943p_regd:
1944	.long	p_dyd0
1945	.long	p_dyd1
1946	.long	p_dyd2
1947	.long	p_dyd3
1948	.long	p_dyd4
1949	.long	p_dyd5
1950	.long	p_dyd6
1951	.long	p_dyd7
1952
1953pack_out:
1954	leal	p_movet,%a0	|load jmp table address
1955	movew	STAG(%a6),%d0	|get source tag
1956	bfextu	%d0{#16:#3},%d0	|isolate source bits
1957	movel	(%a0,%d0.w*4),%a0	|load a0 with routine label for tag
1958	jmp	(%a0)		|go to the routine
1959
1960p_write:
1961	movel	#0x0c,%d0	|get byte count
1962	movel	EXC_EA(%a6),%a1	|get the destination address
1963	bsr	mem_write	|write the user's destination
1964	moveb	#0,CU_SAVEPC(%a6) |set the cu save pc to all 0's
1965
1966|
1967| Also note that the dtag must be set to norm here - this is because
1968| the 040 uses the dtag to execute the correct microcode.
1969|
1970        bfclr    DTAG(%a6){#0:#3}  |set dtag to norm
1971
1972	rts
1973
1974| Notes on handling of special case (zero, inf, and nan) inputs:
1975|	1. Operr is not signalled if the k-factor is greater than 18.
1976|	2. Per the manual, status bits are not set.
1977|
1978
1979p_move:
1980	movew	CMDREG1B(%a6),%d0
1981	btstl	#kfact_bit,%d0	|test for dynamic k-factor
1982	beqs	statick		|if clear, k-factor is static
1983dynamick:
1984	bfextu	%d0{#25:#3},%d0	|isolate register for dynamic k-factor
1985	lea	p_regd,%a0
1986	movel	%a0@(%d0:l:4),%a0
1987	jmp	(%a0)
1988statick:
1989	andiw	#0x007f,%d0	|get k-factor
1990	bfexts	%d0{#25:#7},%d0	|sign extend d0 for bindec
1991	leal	ETEMP(%a6),%a0	|a0 will point to the packed decimal
1992	bsrl	bindec		|perform the convert; data at a6
1993	leal	FP_SCR1(%a6),%a0	|load a0 with result address
1994	bral	p_write
1995p_movez:
1996	leal	ETEMP(%a6),%a0	|a0 will point to the packed decimal
1997	clrw	2(%a0)		|clear lower word of exp
1998	clrl	4(%a0)		|load second lword of ZERO
1999	clrl	8(%a0)		|load third lword of ZERO
2000	bra	p_write		|go write results
2001p_movei:
2002	fmovel	#0,%FPSR		|clear aiop
2003	leal	ETEMP(%a6),%a0	|a0 will point to the packed decimal
2004	clrw	2(%a0)		|clear lower word of exp
2005	bra	p_write		|go write the result
2006p_moven:
2007	leal	ETEMP(%a6),%a0	|a0 will point to the packed decimal
2008	clrw	2(%a0)		|clear lower word of exp
2009	bra	p_write		|go write the result
2010
2011|
2012| Routines to read the dynamic k-factor from Dn.
2013|
2014p_dyd0:
2015	movel	USER_D0(%a6),%d0
2016	bras	statick
2017p_dyd1:
2018	movel	USER_D1(%a6),%d0
2019	bras	statick
2020p_dyd2:
2021	movel	%d2,%d0
2022	bras	statick
2023p_dyd3:
2024	movel	%d3,%d0
2025	bras	statick
2026p_dyd4:
2027	movel	%d4,%d0
2028	bras	statick
2029p_dyd5:
2030	movel	%d5,%d0
2031	bras	statick
2032p_dyd6:
2033	movel	%d6,%d0
2034	bra	statick
2035p_dyd7:
2036	movel	%d7,%d0
2037	bra	statick
2038
2039	|end
2040