aboutsummaryrefslogtreecommitdiffstats
path: root/src/vhdl/vhdl-ieee-std_logic_1164.adb
blob: 93c8dec8ebb60b281bc2b20ae4d1c00ba46fb914 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
--  Nodes recognizer for ieee.std_logic_1164.
--  Copyright (C) 2002, 2003, 2004, 2005 Tristan Gingold
--
--  This program is free software: you can redistribute it and/or modify
--  it under the terms of the GNU General Public License as published by
--  the Free Software Foundation, either version 2 of the License, or
--  (at your option) any later version.
--
--  This program is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU General Public License for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with this program.  If not, see <gnu.org/licenses>.
with Types; use Types;
with Name_Table;
with Std_Names; use Std_Names;
with Vhdl.Errors; use Vhdl.Errors;
with Vhdl.Utils; use Vhdl.Utils;
with Vhdl.Std_Package;

package body Vhdl.Ieee.Std_Logic_1164 is
   function Is_Scalar_Parameter (Inter : Iir) return Boolean is
   begin
      return Get_Base_Type (Get_Type (Inter)) = Std_Ulogic_Type;
   end Is_Scalar_Parameter;

   function Is_Vector_Parameter (Inter : Iir) return Boolean
   is
      Base_Type : constant Iir := Get_Base_Type (Get_Type (Inter));
   begin
      return Base_Type = Std_Ulogic_Vector_Type
        or Base_Type = Std_Logic_Vector_Type;
   end Is_Vector_Parameter;

   function Is_Bitvec_Parameter (Inter : Iir) return Boolean
   is
      Base_Type : constant Iir := Get_Base_Type (Get_Type (Inter));
   begin
      return Base_Type = Std_Package.Bit_Vector_Type_Definition;
   end Is_Bitvec_Parameter;

   function Is_Bit_Parameter (Inter : Iir) return Boolean
   is
      Base_Type : constant Iir := Get_Base_Type (Get_Type (Inter));
   begin
      return Base_Type = Std_Package.Bit_Type_Definition;
   end Is_Bit_Parameter;

   function Is_Integer_Parameter (Inter : Iir) return Boolean is
   begin
      return (Get_Base_Type (Get_Type (Inter))
                = Std_Package.Integer_Type_Definition);
   end Is_Integer_Parameter;

   --  Return True iff the profile of FUNC is: (l, r : std_ulogic)
   function Is_Scalar_Scalar_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
      Inter2 : Iir;
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Scalar_Parameter (Inter) then
         return False;
      end if;
      Inter2 := Get_Chain (Inter);
      if Inter2 =  Null_Iir or else not Is_Scalar_Parameter (Inter2) then
         return False;
      end if;
      if Get_Chain (Inter2) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Scalar_Scalar_Function;

   --  Return True iff the profile of FUNC is: (l : std_ulogic)
   function Is_Scalar_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Scalar_Parameter (Inter) then
         return False;
      end if;
      if Get_Chain (Inter) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Scalar_Function;

   --  Return True iff the profile of FUNC is: (l, r : std_[u]logic_vector)
   function Is_Vector_Vector_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
      Inter2 : Iir;
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Vector_Parameter (Inter) then
         return False;
      end if;
      Inter2 := Get_Chain (Inter);
      if Inter2 =  Null_Iir or else not Is_Vector_Parameter (Inter2) then
         return False;
      end if;
      if Get_Chain (Inter2) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Vector_Vector_Function;

   --  Return True iff the profile of FUNC is:
   --    (l : std_[u]logic_vector; r : integer)
   function Is_Vector_Integer_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
      Inter2 : Iir;
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Vector_Parameter (Inter) then
         return False;
      end if;
      Inter2 := Get_Chain (Inter);
      if Inter2 =  Null_Iir or else not Is_Integer_Parameter (Inter2) then
         return False;
      end if;
      if Get_Chain (Inter2) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Vector_Integer_Function;

   --  Return True iff the profile of FUNC is:
   --    (l : std_[u]logic_vector; r : std_ulogic)
   function Is_Suv_Log_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
      Inter2 : Iir;
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Vector_Parameter (Inter) then
         return False;
      end if;
      Inter2 := Get_Chain (Inter);
      if Inter2 =  Null_Iir or else not Is_Scalar_Parameter (Inter2) then
         return False;
      end if;
      if Get_Chain (Inter2) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Suv_Log_Function;

   --  Return True iff the profile of FUNC is:
   --    (l : std_ulogic; r: std_[u]logic_vector)
   function Is_Log_Suv_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
      Inter2 : Iir;
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Scalar_Parameter (Inter) then
         return False;
      end if;
      Inter2 := Get_Chain (Inter);
      if Inter2 =  Null_Iir or else not Is_Vector_Parameter (Inter2) then
         return False;
      end if;
      if Get_Chain (Inter2) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Log_Suv_Function;

   --  Return True iff the profile of FUNC is: (l : std_[u]logic_vector)
   function Is_Vector_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Vector_Parameter (Inter) then
         return False;
      end if;
      if Get_Chain (Inter) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Vector_Function;

   --  Return True iff the profile of FUNC is: (l : bit_vector)
   function Is_Bitvec_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Bitvec_Parameter (Inter) then
         return False;
      end if;
      if Get_Chain (Inter) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Bitvec_Function;

   --  Return True iff the profile of FUNC is: (l : bit)
   function Is_Bit_Function (Func : Iir) return Boolean
   is
      Inter : constant Iir := Get_Interface_Declaration_Chain (Func);
   begin
      if Get_Implicit_Definition (Func) /= Iir_Predefined_None then
         return False;
      end if;
      if Inter = Null_Iir or else not Is_Bit_Parameter (Inter) then
         return False;
      end if;
      if Get_Chain (Inter) /= Null_Iir then
         return False;
      end if;

      return True;
   end Is_Bit_Function;

   procedure Extract_Declarations (Pkg : Iir_Package_Declaration)
   is
      Error : exception;

      Decl : Iir;
      Def : Iir;
      Predefined : Iir_Predefined_Functions;
   begin
      Std_Logic_1164_Pkg := Pkg;

      Decl := Get_Declaration_Chain (Pkg);

      --  Skip a potential copyright constant.
      Decl := Skip_Copyright_Notice (Decl);

      --  The first declaration should be type std_ulogic.
      if Decl = Null_Iir
        or else Get_Kind (Decl) /= Iir_Kind_Type_Declaration
        or else Get_Identifier (Decl) /= Name_Std_Ulogic
      then
         raise Error;
      end if;

      Def := Get_Type_Definition (Decl);
      if Get_Kind (Def) /= Iir_Kind_Enumeration_Type_Definition then
         raise Error;
      end if;
      Std_Ulogic_Type := Def;

      --  Get node of some literals.
      declare
         use Name_Table;
         Lit_List : constant Iir_Flist := Get_Enumeration_Literal_List (Def);
      begin
         if Get_Nbr_Elements (Lit_List) /= 9 then
            raise Error;
         end if;
         Std_Ulogic_0 := Get_Nth_Element (Lit_List, 2);
         Std_Ulogic_1 := Get_Nth_Element (Lit_List, 3);
         if Get_Identifier (Std_Ulogic_0) /= Get_Identifier ('0')
           or else Get_Identifier (Std_Ulogic_1) /= Get_Identifier ('1')
         then
            raise Error;
         end if;
      end;

      --  The second declaration should be std_ulogic_vector.
      Decl := Get_Chain (Decl);
      Decl := Skip_Implicit (Decl);
      if Decl = Null_Iir
        or else Get_Kind (Decl) /= Iir_Kind_Type_Declaration
        or else Get_Identifier (Decl) /= Name_Std_Ulogic_Vector
      then
         raise Error;
      end if;
      Def := Get_Type_Definition (Decl);
      if Get_Kind (Def) /= Iir_Kind_Array_Type_Definition then
         raise Error;
      end if;
      Std_Ulogic_Vector_Type := Def;

      --  The third declaration should be resolved.
      Decl := Get_Chain (Decl);
      Decl := Skip_Implicit (Decl);
      if Decl = Null_Iir
        or else Get_Kind (Decl) /= Iir_Kind_Function_Declaration
      then
         --  FIXME: check name ?
         raise Error;
      end if;
      Resolved := Decl;

      --  The fourth declaration should be std_logic.
      Decl := Get_Chain (Decl);
      Decl := Skip_Implicit (Decl);
      if Decl = Null_Iir
        or else Get_Kind (Decl) /= Iir_Kind_Subtype_Declaration
        or else Get_Identifier (Decl) /= Name_Std_Logic
      then
         raise Error;
      end if;
      Def := Get_Type (Decl);
      if Get_Kind (Def) /= Iir_Kind_Enumeration_Subtype_Definition then
         raise Error;
      end if;
      Std_Logic_Type := Def;

      --  The fifth declaration should be std_logic_vector.
      Decl := Get_Chain (Decl);
      Decl := Skip_Implicit (Decl);
      if Decl = Null_Iir
        or else (Get_Kind (Decl) /= Iir_Kind_Type_Declaration
                   and then Get_Kind (Decl) /= Iir_Kind_Subtype_Declaration)
        or else Get_Identifier (Decl) /= Name_Std_Logic_Vector
      then
         raise Error;
      end if;
      Def := Get_Type (Decl);
--      if Get_Kind (Def) /= Iir_Kind_Array_Type_Definition then
--         raise Error;
--      end if;
      Std_Logic_Vector_Type := Def;

      --  Skip any declarations but functions.
      loop
         Decl := Get_Chain (Decl);
         exit when Decl = Null_Iir;

         --  Recognize not-predefined functions.
         if Get_Kind (Decl) = Iir_Kind_Function_Declaration
           and then Get_Implicit_Definition (Decl) = Iir_Predefined_None
         then
            --  Useless assignment ?
            Predefined := Iir_Predefined_None;

            case Get_Identifier (Decl) is
               when Name_Rising_Edge =>
                  Predefined := Iir_Predefined_Ieee_1164_Rising_Edge;
                  --  Since rising_edge does not read activity of its
                  --  parameter, clear the flag to allow more optimizations.
                  Set_Has_Active_Flag
                    (Get_Interface_Declaration_Chain (Decl), False);
               when Name_Falling_Edge =>
                  Predefined := Iir_Predefined_Ieee_1164_Falling_Edge;
                  --  Since falling_edge does not read activity of its
                  --  parameter, clear the flag to allow more optimizations.
                  Set_Has_Active_Flag
                    (Get_Interface_Declaration_Chain (Decl), False);
               when Name_To_Bit =>
                  Predefined := Iir_Predefined_Ieee_1164_To_Bit;
               when Name_To_Bitvector =>
                  Predefined := Iir_Predefined_Ieee_1164_To_Bitvector;
               when Name_To_Stdulogic =>
                  Predefined := Iir_Predefined_Ieee_1164_To_Stdulogic;
               when Name_To_Stdlogicvector =>
                  if Is_Vector_Function (Decl) then
                     Predefined :=
                       Iir_Predefined_Ieee_1164_To_Stdlogicvector_Suv;
                  elsif Is_Bitvec_Function (Decl) then
                     Predefined :=
                       Iir_Predefined_Ieee_1164_To_Stdlogicvector_Bv;
                  end if;
               when Name_To_Stdulogicvector =>
                  if Is_Vector_Function (Decl) then
                     Predefined :=
                       Iir_Predefined_Ieee_1164_To_Stdulogicvector_Slv;
                  elsif Is_Bitvec_Function (Decl) then
                     Predefined :=
                       Iir_Predefined_Ieee_1164_To_Stdulogicvector_Bv;
                  end if;
               when Name_To_01 =>
                  if Is_Suv_Log_Function (Decl) then
                     --  TODO: distinguish slv/suv.
                     Predefined := Iir_Predefined_Ieee_1164_To_01_Slv_Log;
                  elsif Is_Scalar_Scalar_Function (Decl) then
                     Predefined := Iir_Predefined_Ieee_1164_To_01_Log_Log;
                  end if;
               when Name_To_X01 =>
                  if Is_Vector_Function (Decl) then
                     --  TODO: distinguish slv/suv.
                     Predefined := Iir_Predefined_Ieee_1164_To_X01_Slv;
                  elsif Is_Scalar_Function (Decl) then
                     Predefined := Iir_Predefined_Ieee_1164_To_X01_Log;
                  elsif Is_Bit_Function (Decl) then
                     Predefined := Iir_Predefined_Ieee_1164_To_X01_Bit_Log;
                  end if;
               when Name_To_UX01 =>
                  if Is_Vector_Function (Decl) then
                     --  TODO: distinguish slv/suv.
                     Predefined := Iir_Predefined_Ieee_1164_To_UX01_Slv;
                  elsif Is_Scalar_Function (Decl) then
                     Predefined := Iir_Predefined_Ieee_1164_To_UX01_Log;
                  end if;
               when Name_To_X01Z =>
                  if Is_Vector_Function (Decl) then
                     --  TODO: distinguish slv/suv.
                     Predefined := Iir_Predefined_Ieee_1164_To_X01Z_Slv;
                  elsif Is_Scalar_Function (Decl) then
                     Predefined := Iir_Predefined_Ieee_1164_To_X01Z_Log;
                  end if;
               when Name_To_Hstring =>
                  Predefined := Iir_Predefined_Ieee_1164_To_Hstring;
               when Name_To_Ostring =>
                  Predefined := Iir_Predefined_Ieee_1164_To_Ostring;
               when others =>
                  if Is_Scalar_Scalar_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_And =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_And;
                        when Name_Nand =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Nand;
                        when Name_Or =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Or;
                        when Name_Nor =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Nor;
                        when Name_Xor =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Xor;
                        when Name_Xnor =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Xnor;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Scalar_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_Not =>
                           Predefined := Iir_Predefined_Ieee_1164_Scalar_Not;
                        when Name_Op_Condition =>
                           Predefined :=
                             Iir_Predefined_Ieee_1164_Condition_Operator;
                        when Name_Is_X =>
                           Predefined := Iir_Predefined_Ieee_1164_Is_X_Log;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Vector_Vector_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_And =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_And;
                        when Name_Nand =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Nand;
                        when Name_Or =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Or;
                        when Name_Nor =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Nor;
                        when Name_Xor =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Xor;
                        when Name_Xnor =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Xnor;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Vector_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_Not =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Not;
                        when Name_And =>
                           Predefined := Iir_Predefined_Ieee_1164_And_Suv;
                        when Name_Nand =>
                           Predefined := Iir_Predefined_Ieee_1164_Nand_Suv;
                        when Name_Or =>
                           Predefined := Iir_Predefined_Ieee_1164_Or_Suv;
                        when Name_Nor =>
                           Predefined := Iir_Predefined_Ieee_1164_Nor_Suv;
                        when Name_Xor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xor_Suv;
                        when Name_Xnor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xnor_Suv;
                        when Name_Is_X =>
                           Predefined := Iir_Predefined_Ieee_1164_Is_X_Slv;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Suv_Log_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_And =>
                           Predefined := Iir_Predefined_Ieee_1164_And_Suv_Log;
                        when Name_Nand =>
                           Predefined := Iir_Predefined_Ieee_1164_Nand_Suv_Log;
                        when Name_Or =>
                           Predefined := Iir_Predefined_Ieee_1164_Or_Suv_Log;
                        when Name_Nor =>
                           Predefined := Iir_Predefined_Ieee_1164_Nor_Suv_Log;
                        when Name_Xor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xor_Suv_Log;
                        when Name_Xnor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xnor_Suv_Log;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Log_Suv_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_And =>
                           Predefined := Iir_Predefined_Ieee_1164_And_Log_Suv;
                        when Name_Nand =>
                           Predefined := Iir_Predefined_Ieee_1164_Nand_Log_Suv;
                        when Name_Or =>
                           Predefined := Iir_Predefined_Ieee_1164_Or_Log_Suv;
                        when Name_Nor =>
                           Predefined := Iir_Predefined_Ieee_1164_Nor_Log_Suv;
                        when Name_Xor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xor_Log_Suv;
                        when Name_Xnor =>
                           Predefined := Iir_Predefined_Ieee_1164_Xnor_Log_Suv;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  elsif Is_Vector_Integer_Function (Decl) then
                     case Get_Identifier (Decl) is
                        when Name_Sll =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Sll;
                        when Name_Srl =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Srl;
                        when Name_Rol =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Rol;
                        when Name_Ror =>
                           Predefined := Iir_Predefined_Ieee_1164_Vector_Ror;
                        when others =>
                           Predefined := Iir_Predefined_None;
                     end case;
                  else
                     Predefined := Iir_Predefined_None;
                  end if;
            end case;
            Set_Implicit_Definition (Decl, Predefined);
         end if;
      end loop;
   exception
      when Error =>
         Error_Msg_Sem (+Pkg, "package ieee.std_logic_1164 is ill-formed");

         --  Clear all definitions.
         Std_Logic_1164_Pkg := Null_Iir;
         Std_Ulogic_Type := Null_Iir;
         Std_Ulogic_Vector_Type := Null_Iir;
         Std_Logic_Type := Null_Iir;
         Std_Logic_Vector_Type := Null_Iir;
         Std_Ulogic_0 := Null_Iir;
         Std_Ulogic_1 := Null_Iir;
   end Extract_Declarations;
end Vhdl.Ieee.Std_Logic_1164;