1 | 1 |
2 | kernel_ex.sa 3.3 12/19/90 2 | kernel_ex.sa 3.3 12/19/90
3 | 3 |
4 | This file contains routines to force excepti 4 | This file contains routines to force exception status in the
5 | fpu for exceptional cases detected or report 5 | fpu for exceptional cases detected or reported within the
6 | transcendental functions. Typically, the t_ 6 | transcendental functions. Typically, the t_xx routine will
7 | set the appropriate bits in the USER_FPSR wo 7 | set the appropriate bits in the USER_FPSR word on the stack.
8 | The bits are tested in gen_except.sa to dete 8 | The bits are tested in gen_except.sa to determine if an exceptional
9 | situation needs to be created on return from 9 | situation needs to be created on return from the FPSP.
10 | 10 |
11 11
12 | Copyright (C) Motorola, Inc. 1 12 | Copyright (C) Motorola, Inc. 1990
13 | All Rights Reserved 13 | All Rights Reserved
14 | 14 |
15 | For details on the license for this fi 15 | For details on the license for this file, please see the
16 | file, README, in this same directory. 16 | file, README, in this same directory.
17 17
18 KERNEL_EX: |idnt 2,1 | Motorola 040 Floa 18 KERNEL_EX: |idnt 2,1 | Motorola 040 Floating Point Software Package
19 19
20 |section 8 20 |section 8
21 21
22 #include "fpsp.h" 22 #include "fpsp.h"
23 23
24 mns_inf: .long 0xffff0000,0x00000000,0x000000 24 mns_inf: .long 0xffff0000,0x00000000,0x00000000
25 pls_inf: .long 0x7fff0000,0x00000000,0x000000 25 pls_inf: .long 0x7fff0000,0x00000000,0x00000000
26 nan: .long 0x7fff0000,0xffffffff,0xffffff 26 nan: .long 0x7fff0000,0xffffffff,0xffffffff
27 huge: .long 0x7ffe0000,0xffffffff,0xffffff 27 huge: .long 0x7ffe0000,0xffffffff,0xffffffff
28 28
29 |xref ovf_r_k 29 |xref ovf_r_k
30 |xref unf_sub 30 |xref unf_sub
31 |xref nrm_set 31 |xref nrm_set
32 32
33 .global t_dz 33 .global t_dz
34 .global t_dz2 34 .global t_dz2
35 .global t_operr 35 .global t_operr
36 .global t_unfl 36 .global t_unfl
37 .global t_ovfl 37 .global t_ovfl
38 .global t_ovfl2 38 .global t_ovfl2
39 .global t_inx2 39 .global t_inx2
40 .global t_frcinx 40 .global t_frcinx
41 .global t_extdnrm 41 .global t_extdnrm
42 .global t_resdnrm 42 .global t_resdnrm
43 .global dst_nan 43 .global dst_nan
44 .global src_nan 44 .global src_nan
45 | 45 |
46 | DZ exception 46 | DZ exception
47 | 47 |
48 | 48 |
49 | if dz trap disabled 49 | if dz trap disabled
50 | store properly signed inf (use 50 | store properly signed inf (use sign of etemp) into fp0
51 | set FPSR exception status dz b 51 | set FPSR exception status dz bit, condition code
52 | inf bit, and accrued dz bit 52 | inf bit, and accrued dz bit
53 | return 53 | return
54 | frestore the frame into the ma 54 | frestore the frame into the machine (done by unimp_hd)
55 | 55 |
56 | else dz trap enabled 56 | else dz trap enabled
57 | set exception status bit & acc 57 | set exception status bit & accrued bits in FPSR
58 | set flag to disable sto_res fr 58 | set flag to disable sto_res from corrupting fp register
59 | return 59 | return
60 | frestore the frame into the ma 60 | frestore the frame into the machine (done by unimp_hd)
61 | 61 |
62 | t_dz2 is used by monadic functions such as f 62 | t_dz2 is used by monadic functions such as flogn (from do_func).
63 | t_dz is used by monadic functions such as sa 63 | t_dz is used by monadic functions such as satanh (from the
64 | transcendental function). 64 | transcendental function).
65 | 65 |
66 t_dz2: 66 t_dz2:
67 bsetb #neg_bit,FPSR_CC(%a6) |set n 67 bsetb #neg_bit,FPSR_CC(%a6) |set neg bit in FPSR
68 fmovel #0,%FPSR 68 fmovel #0,%FPSR |clr status bits (Z set)
69 btstb #dz_bit,FPCR_ENABLE(%a6) 69 btstb #dz_bit,FPCR_ENABLE(%a6) |test FPCR for dz exc enabled
70 bnes dz_ena_end 70 bnes dz_ena_end
71 bras m_inf |flogx 71 bras m_inf |flogx always returns -inf
72 t_dz: 72 t_dz:
73 fmovel #0,%FPSR 73 fmovel #0,%FPSR |clr status bits (Z set)
74 btstb #dz_bit,FPCR_ENABLE(%a6) 74 btstb #dz_bit,FPCR_ENABLE(%a6) |test FPCR for dz exc enabled
75 bnes dz_ena 75 bnes dz_ena
76 | 76 |
77 | dz disabled 77 | dz disabled
78 | 78 |
79 btstb #sign_bit,ETEMP_EX(%a6) |check 79 btstb #sign_bit,ETEMP_EX(%a6) |check sign for neg or pos
80 beqs p_inf |branc 80 beqs p_inf |branch if pos sign
81 81
82 m_inf: 82 m_inf:
83 fmovemx mns_inf,%fp0-%fp0 83 fmovemx mns_inf,%fp0-%fp0 |load -inf
84 bsetb #neg_bit,FPSR_CC(%a6) |set n 84 bsetb #neg_bit,FPSR_CC(%a6) |set neg bit in FPSR
85 bras set_fpsr 85 bras set_fpsr
86 p_inf: 86 p_inf:
87 fmovemx pls_inf,%fp0-%fp0 87 fmovemx pls_inf,%fp0-%fp0 |load +inf
88 set_fpsr: 88 set_fpsr:
89 orl #dzinf_mask,USER_FPSR(%a6) |se 89 orl #dzinf_mask,USER_FPSR(%a6) |set I,DZ,ADZ
90 rts 90 rts
91 | 91 |
92 | dz enabled 92 | dz enabled
93 | 93 |
94 dz_ena: 94 dz_ena:
95 btstb #sign_bit,ETEMP_EX(%a6) |check 95 btstb #sign_bit,ETEMP_EX(%a6) |check sign for neg or pos
96 beqs dz_ena_end 96 beqs dz_ena_end
97 bsetb #neg_bit,FPSR_CC(%a6) |set n 97 bsetb #neg_bit,FPSR_CC(%a6) |set neg bit in FPSR
98 dz_ena_end: 98 dz_ena_end:
99 orl #dzinf_mask,USER_FPSR(%a6) |se 99 orl #dzinf_mask,USER_FPSR(%a6) |set I,DZ,ADZ
100 st STORE_FLG(%a6) 100 st STORE_FLG(%a6)
101 rts 101 rts
102 | 102 |
103 | OPERR exception 103 | OPERR exception
104 | 104 |
105 | if (operr trap disabled) 105 | if (operr trap disabled)
106 | set FPSR exception status oper 106 | set FPSR exception status operr bit, condition code
107 | nan bit; Store default NAN int 107 | nan bit; Store default NAN into fp0
108 | frestore the frame into the ma 108 | frestore the frame into the machine (done by unimp_hd)
109 | 109 |
110 | else (operr trap enabled) 110 | else (operr trap enabled)
111 | set FPSR exception status oper 111 | set FPSR exception status operr bit, accrued operr bit
112 | set flag to disable sto_res fr 112 | set flag to disable sto_res from corrupting fp register
113 | frestore the frame into the ma 113 | frestore the frame into the machine (done by unimp_hd)
114 | 114 |
115 t_operr: 115 t_operr:
116 orl #opnan_mask,USER_FPSR(%a6) |se 116 orl #opnan_mask,USER_FPSR(%a6) |set NaN, OPERR, AIOP
117 117
118 btstb #operr_bit,FPCR_ENABLE(%a6) |t 118 btstb #operr_bit,FPCR_ENABLE(%a6) |test FPCR for operr enabled
119 bnes op_ena 119 bnes op_ena
120 120
121 fmovemx nan,%fp0-%fp0 |load 121 fmovemx nan,%fp0-%fp0 |load default nan
122 rts 122 rts
123 op_ena: 123 op_ena:
124 st STORE_FLG(%a6) |do no 124 st STORE_FLG(%a6) |do not corrupt destination
125 rts 125 rts
126 126
127 | 127 |
128 | t_unfl --- UNFL exception 128 | t_unfl --- UNFL exception
129 | 129 |
130 | This entry point is used by all routines req 130 | This entry point is used by all routines requiring unfl, inex2,
131 | aunfl, and ainex to be set on exit. 131 | aunfl, and ainex to be set on exit.
132 | 132 |
133 | On entry, a0 points to the exceptional opera 133 | On entry, a0 points to the exceptional operand. The final exceptional
134 | operand is built in FP_SCR1 and only the sig 134 | operand is built in FP_SCR1 and only the sign from the original operand
135 | is used. 135 | is used.
136 | 136 |
137 t_unfl: 137 t_unfl:
138 clrl FP_SCR1(%a6) |set e 138 clrl FP_SCR1(%a6) |set exceptional operand to zero
139 clrl FP_SCR1+4(%a6) 139 clrl FP_SCR1+4(%a6)
140 clrl FP_SCR1+8(%a6) 140 clrl FP_SCR1+8(%a6)
141 tstb (%a0) |extra 141 tstb (%a0) |extract sign from caller's exop
142 bpls unfl_signok 142 bpls unfl_signok
143 bset #sign_bit,FP_SCR1(%a6) 143 bset #sign_bit,FP_SCR1(%a6)
144 unfl_signok: 144 unfl_signok:
145 leal FP_SCR1(%a6),%a0 145 leal FP_SCR1(%a6),%a0
146 orl #unfinx_mask,USER_FPSR(%a6) 146 orl #unfinx_mask,USER_FPSR(%a6)
147 | ;set U 147 | ;set UNFL, INEX2, AUNFL, AINEX
148 unfl_con: 148 unfl_con:
149 btstb #unfl_bit,FPCR_ENABLE(%a6) 149 btstb #unfl_bit,FPCR_ENABLE(%a6)
150 beqs unfl_dis 150 beqs unfl_dis
151 151
152 unfl_ena: 152 unfl_ena:
153 bfclr STAG(%a6){#5:#3} 153 bfclr STAG(%a6){#5:#3} |clear wbtm66,wbtm1,wbtm0
154 bsetb #wbtemp15_bit,WB_BYTE(%a6) |se 154 bsetb #wbtemp15_bit,WB_BYTE(%a6) |set wbtemp15
155 bsetb #sticky_bit,STICKY(%a6) |set s 155 bsetb #sticky_bit,STICKY(%a6) |set sticky bit
156 156
157 bclrb #E1,E_BYTE(%a6) 157 bclrb #E1,E_BYTE(%a6)
158 158
159 unfl_dis: 159 unfl_dis:
160 bfextu FPCR_MODE(%a6){#0:#2},%d0 160 bfextu FPCR_MODE(%a6){#0:#2},%d0 |get round precision
161 161
162 bclrb #sign_bit,LOCAL_EX(%a0) 162 bclrb #sign_bit,LOCAL_EX(%a0)
163 sne LOCAL_SGN(%a0) |conve 163 sne LOCAL_SGN(%a0) |convert to internal ext format
164 164
165 bsr unf_sub |retur 165 bsr unf_sub |returns IEEE result at a0
166 | ;and s 166 | ;and sets FPSR_CC accordingly
167 167
168 bfclr LOCAL_SGN(%a0){#0:#8} |conve 168 bfclr LOCAL_SGN(%a0){#0:#8} |convert back to IEEE ext format
169 beqs unfl_fin 169 beqs unfl_fin
170 170
171 bsetb #sign_bit,LOCAL_EX(%a0) 171 bsetb #sign_bit,LOCAL_EX(%a0)
172 bsetb #sign_bit,FP_SCR1(%a6) |set s 172 bsetb #sign_bit,FP_SCR1(%a6) |set sign bit of exc operand
173 173
174 unfl_fin: 174 unfl_fin:
175 fmovemx (%a0),%fp0-%fp0 |store 175 fmovemx (%a0),%fp0-%fp0 |store result in fp0
176 rts 176 rts
177 177
178 178
179 | 179 |
180 | t_ovfl2 --- OVFL exception (without in 180 | t_ovfl2 --- OVFL exception (without inex2 returned)
181 | 181 |
182 | This entry is used by scale to force catastr 182 | This entry is used by scale to force catastrophic overflow. The
183 | ovfl, aovfl, and ainex bits are set, but not 183 | ovfl, aovfl, and ainex bits are set, but not the inex2 bit.
184 | 184 |
185 t_ovfl2: 185 t_ovfl2:
186 orl #ovfl_inx_mask,USER_FPSR(%a6) 186 orl #ovfl_inx_mask,USER_FPSR(%a6)
187 movel ETEMP(%a6),FP_SCR1(%a6) 187 movel ETEMP(%a6),FP_SCR1(%a6)
188 movel ETEMP_HI(%a6),FP_SCR1+4(%a6) 188 movel ETEMP_HI(%a6),FP_SCR1+4(%a6)
189 movel ETEMP_LO(%a6),FP_SCR1+8(%a6) 189 movel ETEMP_LO(%a6),FP_SCR1+8(%a6)
190 | 190 |
191 | Check for single or double round precision. 191 | Check for single or double round precision. If single, check if
192 | the lower 40 bits of ETEMP are zero; if not, 192 | the lower 40 bits of ETEMP are zero; if not, set inex2. If double,
193 | check if the lower 21 bits are zero; if not, 193 | check if the lower 21 bits are zero; if not, set inex2.
194 | 194 |
195 moveb FPCR_MODE(%a6),%d0 195 moveb FPCR_MODE(%a6),%d0
196 andib #0xc0,%d0 196 andib #0xc0,%d0
197 beq t_work |if extended, 197 beq t_work |if extended, finish ovfl processing
198 cmpib #0x40,%d0 |test 198 cmpib #0x40,%d0 |test for single
199 bnes t_dbl 199 bnes t_dbl
200 t_sgl: 200 t_sgl:
201 tstb ETEMP_LO(%a6) 201 tstb ETEMP_LO(%a6)
202 bnes t_setinx2 202 bnes t_setinx2
203 movel ETEMP_HI(%a6),%d0 203 movel ETEMP_HI(%a6),%d0
204 andil #0xff,%d0 |look 204 andil #0xff,%d0 |look at only lower 8 bits
205 bnes t_setinx2 205 bnes t_setinx2
206 bra t_work 206 bra t_work
207 t_dbl: 207 t_dbl:
208 movel ETEMP_LO(%a6),%d0 208 movel ETEMP_LO(%a6),%d0
209 andil #0x7ff,%d0 |look at only 209 andil #0x7ff,%d0 |look at only lower 11 bits
210 beq t_work 210 beq t_work
211 t_setinx2: 211 t_setinx2:
212 orl #inex2_mask,USER_FPSR(%a6) 212 orl #inex2_mask,USER_FPSR(%a6)
213 bras t_work 213 bras t_work
214 | 214 |
215 | t_ovfl --- OVFL exception 215 | t_ovfl --- OVFL exception
216 | 216 |
217 |** Note: the exc operand is returned in ETEMP 217 |** Note: the exc operand is returned in ETEMP.
218 | 218 |
219 t_ovfl: 219 t_ovfl:
220 orl #ovfinx_mask,USER_FPSR(%a6) 220 orl #ovfinx_mask,USER_FPSR(%a6)
221 t_work: 221 t_work:
222 btstb #ovfl_bit,FPCR_ENABLE(%a6) |te 222 btstb #ovfl_bit,FPCR_ENABLE(%a6) |test FPCR for ovfl enabled
223 beqs ovf_dis 223 beqs ovf_dis
224 224
225 ovf_ena: 225 ovf_ena:
226 clrl FP_SCR1(%a6) |set e 226 clrl FP_SCR1(%a6) |set exceptional operand
227 clrl FP_SCR1+4(%a6) 227 clrl FP_SCR1+4(%a6)
228 clrl FP_SCR1+8(%a6) 228 clrl FP_SCR1+8(%a6)
229 229
230 bfclr STAG(%a6){#5:#3} 230 bfclr STAG(%a6){#5:#3} |clear wbtm66,wbtm1,wbtm0
231 bclrb #wbtemp15_bit,WB_BYTE(%a6) |cl 231 bclrb #wbtemp15_bit,WB_BYTE(%a6) |clear wbtemp15
232 bsetb #sticky_bit,STICKY(%a6) |set s 232 bsetb #sticky_bit,STICKY(%a6) |set sticky bit
233 233
234 bclrb #E1,E_BYTE(%a6) 234 bclrb #E1,E_BYTE(%a6)
235 | ;fall 235 | ;fall through to disabled case
236 236
237 | For disabled overflow call 'ovf_r_k'. This 237 | For disabled overflow call 'ovf_r_k'. This routine loads the
238 | correct result based on the rounding precisi 238 | correct result based on the rounding precision, destination
239 | format, rounding mode and sign. 239 | format, rounding mode and sign.
240 | 240 |
241 ovf_dis: 241 ovf_dis:
242 bsr ovf_r_k |retur 242 bsr ovf_r_k |returns unsigned ETEMP_EX
243 | ;and s 243 | ;and sets FPSR_CC accordingly.
244 bfclr ETEMP_SGN(%a6){#0:#8} |fix s 244 bfclr ETEMP_SGN(%a6){#0:#8} |fix sign
245 beqs ovf_pos 245 beqs ovf_pos
246 bsetb #sign_bit,ETEMP_EX(%a6) 246 bsetb #sign_bit,ETEMP_EX(%a6)
247 bsetb #sign_bit,FP_SCR1(%a6) |set e 247 bsetb #sign_bit,FP_SCR1(%a6) |set exceptional operand sign
248 ovf_pos: 248 ovf_pos:
249 fmovemx ETEMP(%a6),%fp0-%fp0 249 fmovemx ETEMP(%a6),%fp0-%fp0 |move the result to fp0
250 rts 250 rts
251 251
252 252
253 | 253 |
254 | INEX2 exception 254 | INEX2 exception
255 | 255 |
256 | The inex2 and ainex bits are set. 256 | The inex2 and ainex bits are set.
257 | 257 |
258 t_inx2: 258 t_inx2:
259 orl #inx2a_mask,USER_FPSR(%a6) |se 259 orl #inx2a_mask,USER_FPSR(%a6) |set INEX2, AINEX
260 rts 260 rts
261 261
262 | 262 |
263 | Force Inex2 263 | Force Inex2
264 | 264 |
265 | This routine is called by the transcendental 265 | This routine is called by the transcendental routines to force
266 | the inex2 exception bits set in the FPSR. I 266 | the inex2 exception bits set in the FPSR. If the underflow bit
267 | is set, but the underflow trap was not taken 267 | is set, but the underflow trap was not taken, the aunfl bit in
268 | the FPSR must be set. 268 | the FPSR must be set.
269 | 269 |
270 t_frcinx: 270 t_frcinx:
271 orl #inx2a_mask,USER_FPSR(%a6) |se 271 orl #inx2a_mask,USER_FPSR(%a6) |set INEX2, AINEX
272 btstb #unfl_bit,FPSR_EXCEPT(%a6) |te 272 btstb #unfl_bit,FPSR_EXCEPT(%a6) |test for unfl bit set
273 beqs no_uacc1 |if cl 273 beqs no_uacc1 |if clear, do not set aunfl
274 bsetb #aunfl_bit,FPSR_AEXCEPT(%a6) 274 bsetb #aunfl_bit,FPSR_AEXCEPT(%a6)
275 no_uacc1: 275 no_uacc1:
276 rts 276 rts
277 277
278 | 278 |
279 | DST_NAN 279 | DST_NAN
280 | 280 |
281 | Determine if the destination nan is signalli 281 | Determine if the destination nan is signalling or non-signalling,
282 | and set the FPSR bits accordingly. See the 282 | and set the FPSR bits accordingly. See the MC68040 User's Manual
283 | section 3.2.2.5 NOT-A-NUMBERS. 283 | section 3.2.2.5 NOT-A-NUMBERS.
284 | 284 |
285 dst_nan: 285 dst_nan:
286 btstb #sign_bit,FPTEMP_EX(%a6) |test 286 btstb #sign_bit,FPTEMP_EX(%a6) |test sign of nan
287 beqs dst_pos |if cl 287 beqs dst_pos |if clr, it was positive
288 bsetb #neg_bit,FPSR_CC(%a6) |set N 288 bsetb #neg_bit,FPSR_CC(%a6) |set N bit
289 dst_pos: 289 dst_pos:
290 btstb #signan_bit,FPTEMP_HI(%a6) |ch 290 btstb #signan_bit,FPTEMP_HI(%a6) |check if signalling
291 beqs dst_snan |branc 291 beqs dst_snan |branch if signalling
292 292
293 fmovel %d1,%fpcr 293 fmovel %d1,%fpcr |restore user's rmode/prec
294 fmovex FPTEMP(%a6),%fp0 |retur 294 fmovex FPTEMP(%a6),%fp0 |return the non-signalling nan
295 | 295 |
296 | Check the source nan. If it is signalling, 296 | Check the source nan. If it is signalling, snan will be reported.
297 | 297 |
298 moveb STAG(%a6),%d0 298 moveb STAG(%a6),%d0
299 andib #0xe0,%d0 299 andib #0xe0,%d0
300 cmpib #0x60,%d0 300 cmpib #0x60,%d0
301 bnes no_snan 301 bnes no_snan
302 btstb #signan_bit,ETEMP_HI(%a6) |che 302 btstb #signan_bit,ETEMP_HI(%a6) |check if signalling
303 bnes no_snan 303 bnes no_snan
304 orl #snaniop_mask,USER_FPSR(%a6) | 304 orl #snaniop_mask,USER_FPSR(%a6) |set NAN, SNAN, AIOP
305 no_snan: 305 no_snan:
306 rts 306 rts
307 307
308 dst_snan: 308 dst_snan:
309 btstb #snan_bit,FPCR_ENABLE(%a6) |ch 309 btstb #snan_bit,FPCR_ENABLE(%a6) |check if trap enabled
310 beqs dst_dis |branc 310 beqs dst_dis |branch if disabled
311 311
312 orb #nan_tag,DTAG(%a6) |set u 312 orb #nan_tag,DTAG(%a6) |set up dtag for nan
313 st STORE_FLG(%a6) |do no 313 st STORE_FLG(%a6) |do not store a result
314 orl #snaniop_mask,USER_FPSR(%a6) | 314 orl #snaniop_mask,USER_FPSR(%a6) |set NAN, SNAN, AIOP
315 rts 315 rts
316 316
317 dst_dis: 317 dst_dis:
318 bsetb #signan_bit,FPTEMP_HI(%a6) |se 318 bsetb #signan_bit,FPTEMP_HI(%a6) |set SNAN bit in sop
319 fmovel %d1,%fpcr 319 fmovel %d1,%fpcr |restore user's rmode/prec
320 fmovex FPTEMP(%a6),%fp0 |load 320 fmovex FPTEMP(%a6),%fp0 |load non-sign. nan
321 orl #snaniop_mask,USER_FPSR(%a6) | 321 orl #snaniop_mask,USER_FPSR(%a6) |set NAN, SNAN, AIOP
322 rts 322 rts
323 323
324 | 324 |
325 | SRC_NAN 325 | SRC_NAN
326 | 326 |
327 | Determine if the source nan is signalling or 327 | Determine if the source nan is signalling or non-signalling,
328 | and set the FPSR bits accordingly. See the 328 | and set the FPSR bits accordingly. See the MC68040 User's Manual
329 | section 3.2.2.5 NOT-A-NUMBERS. 329 | section 3.2.2.5 NOT-A-NUMBERS.
330 | 330 |
331 src_nan: 331 src_nan:
332 btstb #sign_bit,ETEMP_EX(%a6) |test 332 btstb #sign_bit,ETEMP_EX(%a6) |test sign of nan
333 beqs src_pos |if cl 333 beqs src_pos |if clr, it was positive
334 bsetb #neg_bit,FPSR_CC(%a6) |set N 334 bsetb #neg_bit,FPSR_CC(%a6) |set N bit
335 src_pos: 335 src_pos:
336 btstb #signan_bit,ETEMP_HI(%a6) |che 336 btstb #signan_bit,ETEMP_HI(%a6) |check if signalling
337 beqs src_snan |branc 337 beqs src_snan |branch if signalling
338 fmovel %d1,%fpcr 338 fmovel %d1,%fpcr |restore user's rmode/prec
339 fmovex ETEMP(%a6),%fp0 |retur 339 fmovex ETEMP(%a6),%fp0 |return the non-signalling nan
340 rts 340 rts
341 341
342 src_snan: 342 src_snan:
343 btstb #snan_bit,FPCR_ENABLE(%a6) |ch 343 btstb #snan_bit,FPCR_ENABLE(%a6) |check if trap enabled
344 beqs src_dis |branc 344 beqs src_dis |branch if disabled
345 bsetb #signan_bit,ETEMP_HI(%a6) |set 345 bsetb #signan_bit,ETEMP_HI(%a6) |set SNAN bit in sop
346 orb #norm_tag,DTAG(%a6) |set u 346 orb #norm_tag,DTAG(%a6) |set up dtag for norm
347 orb #nan_tag,STAG(%a6) |set u 347 orb #nan_tag,STAG(%a6) |set up stag for nan
348 st STORE_FLG(%a6) |do no 348 st STORE_FLG(%a6) |do not store a result
349 orl #snaniop_mask,USER_FPSR(%a6) | 349 orl #snaniop_mask,USER_FPSR(%a6) |set NAN, SNAN, AIOP
350 rts 350 rts
351 351
352 src_dis: 352 src_dis:
353 bsetb #signan_bit,ETEMP_HI(%a6) |set 353 bsetb #signan_bit,ETEMP_HI(%a6) |set SNAN bit in sop
354 fmovel %d1,%fpcr 354 fmovel %d1,%fpcr |restore user's rmode/prec
355 fmovex ETEMP(%a6),%fp0 |load 355 fmovex ETEMP(%a6),%fp0 |load non-sign. nan
356 orl #snaniop_mask,USER_FPSR(%a6) | 356 orl #snaniop_mask,USER_FPSR(%a6) |set NAN, SNAN, AIOP
357 rts 357 rts
358 358
359 | 359 |
360 | For all functions that have a denormalized i 360 | For all functions that have a denormalized input and that f(x)=x,
361 | this is the entry point 361 | this is the entry point
362 | 362 |
363 t_extdnrm: 363 t_extdnrm:
364 orl #unfinx_mask,USER_FPSR(%a6) 364 orl #unfinx_mask,USER_FPSR(%a6)
365 | ;set U 365 | ;set UNFL, INEX2, AUNFL, AINEX
366 bras xdnrm_con 366 bras xdnrm_con
367 | 367 |
368 | Entry point for scale with extended denorm. 368 | Entry point for scale with extended denorm. The function does
369 | not set inex2, aunfl, or ainex. 369 | not set inex2, aunfl, or ainex.
370 | 370 |
371 t_resdnrm: 371 t_resdnrm:
372 orl #unfl_mask,USER_FPSR(%a6) 372 orl #unfl_mask,USER_FPSR(%a6)
373 373
374 xdnrm_con: 374 xdnrm_con:
375 btstb #unfl_bit,FPCR_ENABLE(%a6) 375 btstb #unfl_bit,FPCR_ENABLE(%a6)
376 beqs xdnrm_dis 376 beqs xdnrm_dis
377 377
378 | 378 |
379 | If exceptions are enabled, the additional ta 379 | If exceptions are enabled, the additional task of setting up WBTEMP
380 | is needed so that when the underflow excepti 380 | is needed so that when the underflow exception handler is entered,
381 | the user perceives no difference between wha 381 | the user perceives no difference between what the 040 provides vs.
382 | what the FPSP provides. 382 | what the FPSP provides.
383 | 383 |
384 xdnrm_ena: 384 xdnrm_ena:
385 movel %a0,-(%a7) 385 movel %a0,-(%a7)
386 386
387 movel LOCAL_EX(%a0),FP_SCR1(%a6) 387 movel LOCAL_EX(%a0),FP_SCR1(%a6)
388 movel LOCAL_HI(%a0),FP_SCR1+4(%a6) 388 movel LOCAL_HI(%a0),FP_SCR1+4(%a6)
389 movel LOCAL_LO(%a0),FP_SCR1+8(%a6) 389 movel LOCAL_LO(%a0),FP_SCR1+8(%a6)
390 390
391 lea FP_SCR1(%a6),%a0 391 lea FP_SCR1(%a6),%a0
392 392
393 bclrb #sign_bit,LOCAL_EX(%a0) 393 bclrb #sign_bit,LOCAL_EX(%a0)
394 sne LOCAL_SGN(%a0) |conve 394 sne LOCAL_SGN(%a0) |convert to internal ext format
395 tstw LOCAL_EX(%a0) |check 395 tstw LOCAL_EX(%a0) |check if input is denorm
396 beqs xdnrm_dn |if so 396 beqs xdnrm_dn |if so, skip nrm_set
397 bsr nrm_set |norma 397 bsr nrm_set |normalize the result (exponent
398 | ;will 398 | ;will be negative
399 xdnrm_dn: 399 xdnrm_dn:
400 bclrb #sign_bit,LOCAL_EX(%a0) |take 400 bclrb #sign_bit,LOCAL_EX(%a0) |take off false sign
401 bfclr LOCAL_SGN(%a0){#0:#8} |chang 401 bfclr LOCAL_SGN(%a0){#0:#8} |change back to IEEE ext format
402 beqs xdep 402 beqs xdep
403 bsetb #sign_bit,LOCAL_EX(%a0) 403 bsetb #sign_bit,LOCAL_EX(%a0)
404 xdep: 404 xdep:
405 bfclr STAG(%a6){#5:#3} 405 bfclr STAG(%a6){#5:#3} |clear wbtm66,wbtm1,wbtm0
406 bsetb #wbtemp15_bit,WB_BYTE(%a6) |se 406 bsetb #wbtemp15_bit,WB_BYTE(%a6) |set wbtemp15
407 bclrb #sticky_bit,STICKY(%a6) |clear 407 bclrb #sticky_bit,STICKY(%a6) |clear sticky bit
408 bclrb #E1,E_BYTE(%a6) 408 bclrb #E1,E_BYTE(%a6)
409 movel (%a7)+,%a0 409 movel (%a7)+,%a0
410 xdnrm_dis: 410 xdnrm_dis:
411 bfextu FPCR_MODE(%a6){#0:#2},%d0 411 bfextu FPCR_MODE(%a6){#0:#2},%d0 |get round precision
412 bnes not_ext |if no 412 bnes not_ext |if not round extended, store
413 | ;IEEE 413 | ;IEEE defaults
414 is_ext: 414 is_ext:
415 btstb #sign_bit,LOCAL_EX(%a0) 415 btstb #sign_bit,LOCAL_EX(%a0)
416 beqs xdnrm_store 416 beqs xdnrm_store
417 417
418 bsetb #neg_bit,FPSR_CC(%a6) |set N 418 bsetb #neg_bit,FPSR_CC(%a6) |set N bit in FPSR_CC
419 419
420 bras xdnrm_store 420 bras xdnrm_store
421 421
422 not_ext: 422 not_ext:
423 bclrb #sign_bit,LOCAL_EX(%a0) 423 bclrb #sign_bit,LOCAL_EX(%a0)
424 sne LOCAL_SGN(%a0) |conve 424 sne LOCAL_SGN(%a0) |convert to internal ext format
425 bsr unf_sub |retur 425 bsr unf_sub |returns IEEE result pointed by
426 | ;a0; s 426 | ;a0; sets FPSR_CC accordingly
427 bfclr LOCAL_SGN(%a0){#0:#8} |conve 427 bfclr LOCAL_SGN(%a0){#0:#8} |convert back to IEEE ext format
428 beqs xdnrm_store 428 beqs xdnrm_store
429 bsetb #sign_bit,LOCAL_EX(%a0) 429 bsetb #sign_bit,LOCAL_EX(%a0)
430 xdnrm_store: 430 xdnrm_store:
431 fmovemx (%a0),%fp0-%fp0 |store 431 fmovemx (%a0),%fp0-%fp0 |store result in fp0
432 rts 432 rts
433 433
434 | 434 |
435 | This subroutine is used for dyadic operation 435 | This subroutine is used for dyadic operations that use an extended
436 | denorm within the kernel. The approach used 436 | denorm within the kernel. The approach used is to capture the frame,
437 | fix/restore. 437 | fix/restore.
438 | 438 |
439 .global t_avoid_unsupp 439 .global t_avoid_unsupp
440 t_avoid_unsupp: 440 t_avoid_unsupp:
441 link %a2,#-LOCAL_SIZE 441 link %a2,#-LOCAL_SIZE |so that a2 fpsp.h negative
442 | ;offse 442 | ;offsets may be used
443 fsave -(%a7) 443 fsave -(%a7)
444 tstb 1(%a7) |check 444 tstb 1(%a7) |check if idle, exit if so
445 beq idle_end 445 beq idle_end
446 btstb #E1,E_BYTE(%a2) |check 446 btstb #E1,E_BYTE(%a2) |check for an E1 exception if
447 | ;enabl 447 | ;enabled, there is an unsupp
448 beq end_avun |else, 448 beq end_avun |else, exit
449 btstb #7,DTAG(%a2) |check 449 btstb #7,DTAG(%a2) |check for denorm destination
450 beqs src_den |else, 450 beqs src_den |else, must be a source denorm
451 | 451 |
452 | handle destination denorm 452 | handle destination denorm
453 | 453 |
454 lea FPTEMP(%a2),%a0 454 lea FPTEMP(%a2),%a0
455 btstb #sign_bit,LOCAL_EX(%a0) 455 btstb #sign_bit,LOCAL_EX(%a0)
456 sne LOCAL_SGN(%a0) |conve 456 sne LOCAL_SGN(%a0) |convert to internal ext format
457 bclrb #7,DTAG(%a2) |set D 457 bclrb #7,DTAG(%a2) |set DTAG to norm
458 bsr nrm_set |norma 458 bsr nrm_set |normalize result, exponent
459 | ;will 459 | ;will become negative
460 bclrb #sign_bit,LOCAL_EX(%a0) |get r 460 bclrb #sign_bit,LOCAL_EX(%a0) |get rid of fake sign
461 bfclr LOCAL_SGN(%a0){#0:#8} |conve 461 bfclr LOCAL_SGN(%a0){#0:#8} |convert back to IEEE ext format
462 beqs ck_src_den |check 462 beqs ck_src_den |check if source is also denorm
463 bsetb #sign_bit,LOCAL_EX(%a0) 463 bsetb #sign_bit,LOCAL_EX(%a0)
464 ck_src_den: 464 ck_src_den:
465 btstb #7,STAG(%a2) 465 btstb #7,STAG(%a2)
466 beqs end_avun 466 beqs end_avun
467 src_den: 467 src_den:
468 lea ETEMP(%a2),%a0 468 lea ETEMP(%a2),%a0
469 btstb #sign_bit,LOCAL_EX(%a0) 469 btstb #sign_bit,LOCAL_EX(%a0)
470 sne LOCAL_SGN(%a0) |conve 470 sne LOCAL_SGN(%a0) |convert to internal ext format
471 bclrb #7,STAG(%a2) |set S 471 bclrb #7,STAG(%a2) |set STAG to norm
472 bsr nrm_set |norma 472 bsr nrm_set |normalize result, exponent
473 | ;will 473 | ;will become negative
474 bclrb #sign_bit,LOCAL_EX(%a0) |get r 474 bclrb #sign_bit,LOCAL_EX(%a0) |get rid of fake sign
475 bfclr LOCAL_SGN(%a0){#0:#8} |conve 475 bfclr LOCAL_SGN(%a0){#0:#8} |convert back to IEEE ext format
476 beqs den_com 476 beqs den_com
477 bsetb #sign_bit,LOCAL_EX(%a0) 477 bsetb #sign_bit,LOCAL_EX(%a0)
478 den_com: 478 den_com:
479 moveb #0xfe,CU_SAVEPC(%a2) |set c 479 moveb #0xfe,CU_SAVEPC(%a2) |set continue frame
480 clrw NMNEXC(%a2) |clear 480 clrw NMNEXC(%a2) |clear NMNEXC
481 bclrb #E1,E_BYTE(%a2) 481 bclrb #E1,E_BYTE(%a2)
482 | fmove.l %FPSR,FPSR_SHADOW(%a2) 482 | fmove.l %FPSR,FPSR_SHADOW(%a2)
483 | bset.b #SFLAG,E_BYTE(%a2) 483 | bset.b #SFLAG,E_BYTE(%a2)
484 | bset.b #XFLAG,T_BYTE(%a2) 484 | bset.b #XFLAG,T_BYTE(%a2)
485 end_avun: 485 end_avun:
486 frestore (%a7)+ 486 frestore (%a7)+
487 unlk %a2 487 unlk %a2
488 rts 488 rts
489 idle_end: 489 idle_end:
490 addl #4,%a7 490 addl #4,%a7
491 unlk %a2 491 unlk %a2
492 rts 492 rts
493 |end 493 |end
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