aboutsummaryrefslogtreecommitdiff
path: root/opcodes/mep-asm.c
blob: 41a1f92fd092eef769f3c265c30c60e07264bb41 (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
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
/* Assembler interface for targets using CGEN. -*- C -*-
   CGEN: Cpu tools GENerator

   THIS FILE IS MACHINE GENERATED WITH CGEN.
   - the resultant file is machine generated, cgen-asm.in isn't

   Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2005, 2007, 2008
   Free Software Foundation, Inc.

   This file is part of libopcodes.

   This library 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 3, or (at your option)
   any later version.

   It 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, write to the Free Software Foundation, Inc.,
   51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */


/* ??? Eventually more and more of this stuff can go to cpu-independent files.
   Keep that in mind.  */

#include "sysdep.h"
#include <stdio.h>
#include "ansidecl.h"
#include "bfd.h"
#include "symcat.h"
#include "mep-desc.h"
#include "mep-opc.h"
#include "opintl.h"
#include "xregex.h"
#include "libiberty.h"
#include "safe-ctype.h"

#undef  min
#define min(a,b) ((a) < (b) ? (a) : (b))
#undef  max
#define max(a,b) ((a) > (b) ? (a) : (b))

static const char * parse_insn_normal
  (CGEN_CPU_DESC, const CGEN_INSN *, const char **, CGEN_FIELDS *);

/* -- assembler routines inserted here.  */

/* -- asm.c */

#include "elf/mep.h"

#define CGEN_VALIDATE_INSN_SUPPORTED

       const char * parse_csrn       (CGEN_CPU_DESC, const char **, CGEN_KEYWORD *, long *);
       const char * parse_tpreg      (CGEN_CPU_DESC, const char **, CGEN_KEYWORD *, long *);
       const char * parse_spreg      (CGEN_CPU_DESC, const char **, CGEN_KEYWORD *, long *);
       const char * parse_mep_align  (CGEN_CPU_DESC, const char **, enum cgen_operand_type, long *);
       const char * parse_mep_alignu (CGEN_CPU_DESC, const char **, enum cgen_operand_type, unsigned long *);
static const char * parse_signed16   (CGEN_CPU_DESC, const char **, int, long *);
static const char * parse_unsigned16 (CGEN_CPU_DESC, const char **, int, unsigned long *);
static const char * parse_lo16       (CGEN_CPU_DESC, const char **, int, long *, long);
static const char * parse_unsigned7  (CGEN_CPU_DESC, const char **, enum cgen_operand_type, unsigned long *);
static const char * parse_zero       (CGEN_CPU_DESC, const char **, int, long *);

const char *
parse_csrn (CGEN_CPU_DESC cd, const char **strp,
	    CGEN_KEYWORD *keyword_table, long *field)
{
  const char *err;
  unsigned long value;

  err = cgen_parse_keyword (cd, strp, keyword_table, field);
  if (!err)
    return NULL;

  err = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CSRN_IDX, & value);
  if (err)
    return err;
  *field = value;
  return NULL;
}

/* begin-cop-ip-parse-handlers */
/* end-cop-ip-parse-handlers */

const char *
parse_tpreg (CGEN_CPU_DESC cd, const char ** strp,
	     CGEN_KEYWORD *keyword_table, long *field)
{
  const char *err;

  err = cgen_parse_keyword (cd, strp, keyword_table, field);
  if (err)
    return err;
  if (*field != 13)
    return _("Only $tp or $13 allowed for this opcode");
  return NULL;
}

const char *
parse_spreg (CGEN_CPU_DESC cd, const char ** strp,
	     CGEN_KEYWORD *keyword_table, long *field)
{
  const char *err;

  err = cgen_parse_keyword (cd, strp, keyword_table, field);
  if (err)
    return err;
  if (*field != 15)
    return _("Only $sp or $15 allowed for this opcode");
  return NULL;
}

const char *
parse_mep_align (CGEN_CPU_DESC cd, const char ** strp,
		 enum cgen_operand_type type, long *field)
{
  long lsbs = 0;
  const char *err;

  switch (type)
    {
    case MEP_OPERAND_PCREL8A2:
    case MEP_OPERAND_PCREL12A2:
    case MEP_OPERAND_PCREL17A2:
    case MEP_OPERAND_PCREL24A2:
      err = cgen_parse_signed_integer   (cd, strp, type, field);
      break;
    case MEP_OPERAND_PCABS24A2:
    case MEP_OPERAND_UDISP7:
    case MEP_OPERAND_UDISP7A2:
    case MEP_OPERAND_UDISP7A4:
    case MEP_OPERAND_UIMM7A4:
    case MEP_OPERAND_ADDR24A4:
      err = cgen_parse_unsigned_integer (cd, strp, type, (unsigned long *) field);
      break;
    default:
      abort();
    }
  if (err)
    return err;
  switch (type)
    {
    case MEP_OPERAND_UDISP7:
      lsbs = 0;
      break;
    case MEP_OPERAND_PCREL8A2:
    case MEP_OPERAND_PCREL12A2:
    case MEP_OPERAND_PCREL17A2:
    case MEP_OPERAND_PCREL24A2:
    case MEP_OPERAND_PCABS24A2:
    case MEP_OPERAND_UDISP7A2:
      lsbs = *field & 1;
      break;
    case MEP_OPERAND_UDISP7A4:
    case MEP_OPERAND_UIMM7A4:
    case MEP_OPERAND_ADDR24A4:
      lsbs = *field & 3;
      break;
      lsbs = *field & 7;
      break;
    default:
      /* Safe assumption?  */
      abort ();
    }
  if (lsbs)
    return "Value is not aligned enough";
  return NULL;
}

const char *
parse_mep_alignu (CGEN_CPU_DESC cd, const char ** strp,
		 enum cgen_operand_type type, unsigned long *field)
{
  return parse_mep_align (cd, strp, type, (long *) field);
}


/* Handle %lo(), %tpoff(), %sdaoff(), %hi(), and other signed
   constants in a signed context.  */

static const char *
parse_signed16 (CGEN_CPU_DESC cd,
		const char **strp,
		int opindex,
		long *valuep)
{
  return parse_lo16 (cd, strp, opindex, valuep, 1);
}

static const char *
parse_lo16 (CGEN_CPU_DESC cd,
	    const char **strp,
	    int opindex,
	    long *valuep,
	    long signedp)
{
  const char *errmsg;
  enum cgen_parse_operand_result result_type;
  bfd_vma value;

  if (strncasecmp (*strp, "%lo(", 4) == 0)
    {
      *strp += 4;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_LOW16,
				   & result_type, & value);
      if (**strp != ')')
	return _("missing `)'");
      ++*strp;
      if (errmsg == NULL
	  && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
	value &= 0xffff;
      if (signedp)
	*valuep = (long)(short) value;
      else
	*valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%hi(", 4) == 0)
    {
      *strp += 4;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_HI16S,
				   & result_type, & value);
      if (**strp != ')')
	return _("missing `)'");
      ++*strp;
      if (errmsg == NULL
	  && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
	value = (value + 0x8000) >> 16;
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%uhi(", 5) == 0)
    {
      *strp += 5;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_HI16U,
				   & result_type, & value);
      if (**strp != ')')
	return _("missing `)'");
      ++*strp;
      if (errmsg == NULL
	  && result_type == CGEN_PARSE_OPERAND_RESULT_NUMBER)
	value = value >> 16;
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%sdaoff(", 8) == 0)
    {
      *strp += 8;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_GPREL,
				   NULL, & value);
      if (**strp != ')')
	return _("missing `)'");
      ++*strp;
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%tpoff(", 7) == 0)
    {
      *strp += 7;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_TPREL,
				   NULL, & value);
      if (**strp != ')')
	return _("missing `)'");
      ++*strp;
      *valuep = value;
      return errmsg;
    }

  if (**strp == '%')
    return _("invalid %function() here");

  return cgen_parse_signed_integer (cd, strp, opindex, valuep);
}

static const char *
parse_unsigned16 (CGEN_CPU_DESC cd,
		  const char **strp,
		  int opindex,
		  unsigned long *valuep)
{
  return parse_lo16 (cd, strp, opindex, (long *) valuep, 0);
}

/* A special case of parse_signed16 which accepts only the value zero.  */

static const char *
parse_zero (CGEN_CPU_DESC cd, const char **strp, int opindex, long *valuep)
{
  const char *errmsg;
  enum cgen_parse_operand_result result_type;
  bfd_vma value;

  /*fprintf(stderr, "dj: signed parse opindex `%s'\n", *strp);*/

  /* Prevent ($ry) from being attempted as an expression on 'sw $rx,($ry)'.
     It will fail and cause ry to be listed as an undefined symbol in the
     listing.  */
  if (strncmp (*strp, "($", 2) == 0)
    return "not zero"; /* any string will do -- will never be seen.  */

  if (strncasecmp (*strp, "%lo(", 4) == 0)
    {
      *strp += 4;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_LOW16,
				   &result_type, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      if (errmsg == NULL
	  && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
	return "not zero"; /* any string will do -- will never be seen.  */
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%hi(", 4) == 0)
    {
      *strp += 4;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_HI16S,
				   &result_type, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      if (errmsg == NULL
	  && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
	return "not zero"; /* any string will do -- will never be seen.  */
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%uhi(", 5) == 0)
    {
      *strp += 5;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_HI16U,
				   &result_type, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      if (errmsg == NULL
	  && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
	return "not zero"; /* any string will do -- will never be seen.  */
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%sdaoff(", 8) == 0)
    {
      *strp += 8;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_GPREL,
				   &result_type, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      if (errmsg == NULL
	  && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
	return "not zero"; /* any string will do -- will never be seen.  */
      *valuep = value;
      return errmsg;
    }

  if (strncasecmp (*strp, "%tpoff(", 7) == 0)
    {
      *strp += 7;
      errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_MEP_TPREL,
				   &result_type, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      if (errmsg == NULL
	  && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
	return "not zero"; /* any string will do -- will never be seen.  */
      *valuep = value;
      return errmsg;
    }

  if (**strp == '%')
    return "invalid %function() here";

  errmsg = cgen_parse_address (cd, strp, opindex, BFD_RELOC_NONE,
			       &result_type, &value);
  if (errmsg == NULL
      && (result_type != CGEN_PARSE_OPERAND_RESULT_NUMBER || value != 0))
    return "not zero"; /* any string will do -- will never be seen.  */

  return errmsg;
}

static const char *
parse_unsigned7 (CGEN_CPU_DESC cd, const char **strp,
		 enum cgen_operand_type opindex, unsigned long *valuep)
{
  const char *errmsg;
  bfd_vma value;

  /* fprintf(stderr, "dj: unsigned7 parse `%s'\n", *strp); */

  if (strncasecmp (*strp, "%tpoff(", 7) == 0)
    {
      int reloc;
      *strp += 7;
      switch (opindex)
	{
	case MEP_OPERAND_UDISP7:
	  reloc = BFD_RELOC_MEP_TPREL7;
	  break;
	case MEP_OPERAND_UDISP7A2:
	  reloc = BFD_RELOC_MEP_TPREL7A2;
	  break;
	case MEP_OPERAND_UDISP7A4:
	  reloc = BFD_RELOC_MEP_TPREL7A4;
	  break;
	default:
	  /* Safe assumption?  */
	  abort (); 
	}
      errmsg = cgen_parse_address (cd, strp, opindex, reloc,
				   NULL, &value);
      if (**strp != ')')
	return "missing `)'";
      ++*strp;
      *valuep = value;
      return errmsg;
    }

  if (**strp == '%')
    return _("invalid %function() here");

  return parse_mep_alignu (cd, strp, opindex, valuep);
}

static ATTRIBUTE_UNUSED const char *
parse_cdisp10 (CGEN_CPU_DESC cd,
	       const char **strp,
	       int opindex,
	       long *valuep)
{
  const char *errmsg = 0;
  signed long value;
  long have_zero = 0;
  int wide = 0;
  int alignment;

  switch (opindex)
    {
    case MEP_OPERAND_CDISP10A4:
      alignment = 2;
      break;
    case MEP_OPERAND_CDISP10A2:
      alignment = 1;
      break;
    case MEP_OPERAND_CDISP10:
    default:
      alignment = 0;
      break;
    }

  if (MEP_CPU == EF_MEP_CPU_C5)
    wide = 1;

  if (strncmp (*strp, "0x0", 3) == 0 
      || (**strp == '0' && *(*strp + 1) != 'x'))
    have_zero = 1;

  errmsg = cgen_parse_signed_integer (cd, strp, opindex, & value);
  if (errmsg)
    return errmsg;

  if (wide)
    {
      if (value < -512 || value > 511)
	return _("Immediate is out of range -512 to 511");
    }
  else
    {
      if (value < -128 || value > 127)
	return _("Immediate is out of range -128 to 127");
    }

  if (value & ((1<<alignment)-1))
    return _("Value is not aligned enough");

  /* If this field may require a relocation then use larger dsp16.  */
  if (! have_zero && value == 0)
    return (wide ? _("Immediate is out of range -512 to 511")
	    : _("Immediate is out of range -128 to 127"));

  *valuep = value;
  return 0;
}

/* BEGIN LIGHTWEIGHT MACRO PROCESSOR.  */

#define MAXARGS 9

typedef struct
{
  char *name;
  char *expansion;
}  macro;

typedef struct
{
  const char *start;
  int len;
} arg;

macro macros[] =
{
  { "sizeof", "(`1.end + (- `1))"},
  { "startof", "(`1 | 0)" },
  { "align4", "(`1&(~3))"},
/*{ "hi", "(((`1+0x8000)>>16) & 0xffff)" },  */
/*{ "lo", "(`1 & 0xffff)" },  */
/*{ "sdaoff", "((`1-__sdabase) & 0x7f)"},  */
/*{ "tpoff", "((`1-__tpbase) & 0x7f)"},  */
  { 0,0 }
};

static char  * expand_string    (const char *, int);

static const char *
mep_cgen_expand_macros_and_parse_operand
  (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);

static char *
str_append (char *dest, const char *input, int len)
{  
  char *new_dest;
  int oldlen;

  if (len == 0)
    return dest;
  /* printf("str_append: <<%s>>, <<%s>>, %d\n", dest, input, len); */
  oldlen = (dest ? strlen(dest) : 0);
  new_dest = realloc (dest, oldlen + len + 1);
  memset (new_dest + oldlen, 0, len + 1);
  return strncat (new_dest, input, len);
}

static macro *
lookup_macro (const char *name)
{
  macro *m;

  for (m = macros; m->name; ++m)
    if (strncmp (m->name, name, strlen(m->name)) == 0)
      return m;

  return 0;
}

static char *
expand_macro (arg *args, int narg, macro *mac)
{
  char *result = 0, *rescanned_result = 0;
  char *e = mac->expansion;
  char *mark = e;
  int arg = 0;

  /*  printf("expanding macro %s with %d args\n", mac->name, narg + 1); */
  while (*e)
    {
      if (*e == '`' && 
	  (*e+1) && 
	  ((*(e + 1) - '1') <= MAXARGS) &&
	  ((*(e + 1) - '1') <= narg))
	{
	  result = str_append (result, mark, e - mark);
	  arg = (*(e + 1) - '1');
	  /* printf("replacing `%d with %s\n", arg+1, args[arg].start); */
	  result = str_append (result, args[arg].start, args[arg].len);
	  ++e;
	  mark = e+1;
	}
      ++e;
    }

  if (mark != e)
    result = str_append (result, mark, e - mark);

  if (result)
    {
      rescanned_result = expand_string (result, 0);
      free (result);
      return rescanned_result;
    }
  else 
    return result;
}

#define IN_TEXT 0
#define IN_ARGS 1

static char *
expand_string (const char *in, int first_only)
{
  int num_expansions = 0;
  int depth = 0;
  int narg = -1;
  arg args[MAXARGS];
  int state = IN_TEXT;
  const char *mark = in;
  macro *macro = 0;

  char *expansion = 0;
  char *result = 0;

  while (*in)
    {
      switch (state)
	{
	case IN_TEXT:
	  if (*in == '%' && *(in + 1) && (!first_only || num_expansions == 0)) 
	    {	      
	      macro = lookup_macro (in + 1);
	      if (macro)
		{
		  /* printf("entering state %d at '%s'...\n", state, in); */
		  result = str_append (result, mark, in - mark);
		  mark = in;
		  in += 1 + strlen (macro->name);
		  while (*in == ' ') ++in;
		  if (*in != '(')
		    {
		      state = IN_TEXT;		      
		      macro = 0;
		    }
		  else
		    {
		      state = IN_ARGS;
		      narg = 0;
		      args[narg].start = in + 1;
		      args[narg].len = 0;
		      mark = in + 1;	      		      
		    }
		}
	    }
	  break;
	case IN_ARGS:
	  if (depth == 0)
	    {
	      switch (*in)
		{
		case ',':
		  narg++;
		  args[narg].start = (in + 1);
		  args[narg].len = 0;
		  break;
		case ')':
		  state = IN_TEXT;
		  /* printf("entering state %d at '%s'...\n", state, in); */
		  if (macro)
		    {
		      expansion = 0;
		      expansion = expand_macro (args, narg, macro);
		      num_expansions++;
		      if (expansion)
			{
			  result = str_append (result, expansion, strlen (expansion));
			  free (expansion);
			}
		    }
		  else
		    {
		      result = str_append (result, mark, in - mark);
		    }
		  macro = 0;
		  mark = in + 1;
		  break;
		case '(':
		  depth++;
		default:
		  args[narg].len++;
		  break;		  
		}
	    } 
	  else
	    {
	      if (*in == ')')
		depth--;
	      if (narg > -1)
		args[narg].len++;
	    }
	  
	}
      ++in;
    }
  
  if (mark != in)
    result = str_append (result, mark, in - mark);
  
  return result;
}

#undef IN_ARGS
#undef IN_TEXT
#undef MAXARGS


/* END LIGHTWEIGHT MACRO PROCESSOR.  */

const char * mep_cgen_parse_operand
  (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);

const char *
mep_cgen_expand_macros_and_parse_operand (CGEN_CPU_DESC cd, int opindex,
					  const char ** strp_in, CGEN_FIELDS * fields)
{
  const char * errmsg = NULL;
  char *str = 0, *hold = 0;
  const char **strp = 0;

  /* Set up a new pointer to macro-expanded string.  */
  str = expand_string (*strp_in, 1);
  /* fprintf (stderr, " expanded <<%s>> to <<%s>>\n", *strp_in, str); */

  hold = str;
  strp = (const char **)(&str);

  errmsg = mep_cgen_parse_operand (cd, opindex, strp, fields);

  /* Now work out the advance.  */
  if (strlen (str) == 0)
    *strp_in += strlen (*strp_in);

  else
    {
      if (strstr (*strp_in, str))
	/* A macro-expansion was pulled off the front.  */
	*strp_in = strstr (*strp_in, str);  
      else
	/* A non-macro-expansion was pulled off the front.  */
	*strp_in += (str - hold); 
    }

  if (hold)
    free (hold);

  return errmsg;
}

#define CGEN_ASM_INIT_HOOK (cd->parse_operand = mep_cgen_expand_macros_and_parse_operand); 

/* -- dis.c */

const char * mep_cgen_parse_operand
  (CGEN_CPU_DESC, int, const char **, CGEN_FIELDS *);

/* Main entry point for operand parsing.

   This function is basically just a big switch statement.  Earlier versions
   used tables to look up the function to use, but
   - if the table contains both assembler and disassembler functions then
     the disassembler contains much of the assembler and vice-versa,
   - there's a lot of inlining possibilities as things grow,
   - using a switch statement avoids the function call overhead.

   This function could be moved into `parse_insn_normal', but keeping it
   separate makes clear the interface between `parse_insn_normal' and each of
   the handlers.  */

const char *
mep_cgen_parse_operand (CGEN_CPU_DESC cd,
			   int opindex,
			   const char ** strp,
			   CGEN_FIELDS * fields)
{
  const char * errmsg = NULL;
  /* Used by scalar operands that still need to be parsed.  */
  long junk ATTRIBUTE_UNUSED;

  switch (opindex)
    {
    case MEP_OPERAND_ADDR24A4 :
      errmsg = parse_mep_alignu (cd, strp, MEP_OPERAND_ADDR24A4, (unsigned long *) (& fields->f_24u8a4n));
      break;
    case MEP_OPERAND_C5RMUIMM20 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_C5RMUIMM20, (unsigned long *) (& fields->f_c5_rmuimm20));
      break;
    case MEP_OPERAND_C5RNMUIMM24 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_C5RNMUIMM24, (unsigned long *) (& fields->f_c5_rnmuimm24));
      break;
    case MEP_OPERAND_CALLNUM :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CALLNUM, (unsigned long *) (& fields->f_callnum));
      break;
    case MEP_OPERAND_CCCC :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CCCC, (unsigned long *) (& fields->f_rm));
      break;
    case MEP_OPERAND_CCRN :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_ccr, & fields->f_ccrn);
      break;
    case MEP_OPERAND_CDISP10 :
      errmsg = parse_cdisp10 (cd, strp, MEP_OPERAND_CDISP10, (long *) (& fields->f_cdisp10));
      break;
    case MEP_OPERAND_CDISP10A2 :
      errmsg = parse_cdisp10 (cd, strp, MEP_OPERAND_CDISP10A2, (long *) (& fields->f_cdisp10));
      break;
    case MEP_OPERAND_CDISP10A4 :
      errmsg = parse_cdisp10 (cd, strp, MEP_OPERAND_CDISP10A4, (long *) (& fields->f_cdisp10));
      break;
    case MEP_OPERAND_CDISP10A8 :
      errmsg = parse_cdisp10 (cd, strp, MEP_OPERAND_CDISP10A8, (long *) (& fields->f_cdisp10));
      break;
    case MEP_OPERAND_CDISP12 :
      errmsg = cgen_parse_signed_integer (cd, strp, MEP_OPERAND_CDISP12, (long *) (& fields->f_12s20));
      break;
    case MEP_OPERAND_CIMM4 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CIMM4, (unsigned long *) (& fields->f_rn));
      break;
    case MEP_OPERAND_CIMM5 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CIMM5, (unsigned long *) (& fields->f_5u24));
      break;
    case MEP_OPERAND_CODE16 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CODE16, (unsigned long *) (& fields->f_16u16));
      break;
    case MEP_OPERAND_CODE24 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CODE24, (unsigned long *) (& fields->f_24u4n));
      break;
    case MEP_OPERAND_CP_FLAG :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_ccr, & junk);
      break;
    case MEP_OPERAND_CRN :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_cr, & fields->f_crn);
      break;
    case MEP_OPERAND_CRN64 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_cr64, & fields->f_crn);
      break;
    case MEP_OPERAND_CRNX :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_cr, & fields->f_crnx);
      break;
    case MEP_OPERAND_CRNX64 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_cr64, & fields->f_crnx);
      break;
    case MEP_OPERAND_CSRN :
      errmsg = parse_csrn (cd, strp, & mep_cgen_opval_h_csr, & fields->f_csrn);
      break;
    case MEP_OPERAND_CSRN_IDX :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_CSRN_IDX, (unsigned long *) (& fields->f_csrn));
      break;
    case MEP_OPERAND_DBG :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_DEPC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_EPC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_EXC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_HI :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_LO :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_LP :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_MB0 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_MB1 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_ME0 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_ME1 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_NPC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_OPT :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_PCABS24A2 :
      errmsg = parse_mep_alignu (cd, strp, MEP_OPERAND_PCABS24A2, (unsigned long *) (& fields->f_24u5a2n));
      break;
    case MEP_OPERAND_PCREL12A2 :
      errmsg = parse_mep_align (cd, strp, MEP_OPERAND_PCREL12A2, (long *) (& fields->f_12s4a2));
      break;
    case MEP_OPERAND_PCREL17A2 :
      errmsg = parse_mep_align (cd, strp, MEP_OPERAND_PCREL17A2, (long *) (& fields->f_17s16a2));
      break;
    case MEP_OPERAND_PCREL24A2 :
      errmsg = parse_mep_align (cd, strp, MEP_OPERAND_PCREL24A2, (long *) (& fields->f_24s5a2n));
      break;
    case MEP_OPERAND_PCREL8A2 :
      errmsg = parse_mep_align (cd, strp, MEP_OPERAND_PCREL8A2, (long *) (& fields->f_8s8a2));
      break;
    case MEP_OPERAND_PSW :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_R0 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_R1 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_RL :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rl);
      break;
    case MEP_OPERAND_RL5 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rl5);
      break;
    case MEP_OPERAND_RM :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rm);
      break;
    case MEP_OPERAND_RMA :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rm);
      break;
    case MEP_OPERAND_RN :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RN3 :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3C :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3L :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3S :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3UC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3UL :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RN3US :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn3);
      break;
    case MEP_OPERAND_RNC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RNL :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RNS :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RNUC :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RNUL :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_RNUS :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & fields->f_rn);
      break;
    case MEP_OPERAND_SAR :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_csr, & junk);
      break;
    case MEP_OPERAND_SDISP16 :
      errmsg = parse_signed16 (cd, strp, MEP_OPERAND_SDISP16, (long *) (& fields->f_16s16));
      break;
    case MEP_OPERAND_SIMM16 :
      errmsg = parse_signed16 (cd, strp, MEP_OPERAND_SIMM16, (long *) (& fields->f_16s16));
      break;
    case MEP_OPERAND_SIMM6 :
      errmsg = cgen_parse_signed_integer (cd, strp, MEP_OPERAND_SIMM6, (long *) (& fields->f_6s8));
      break;
    case MEP_OPERAND_SIMM8 :
      errmsg = cgen_parse_signed_integer (cd, strp, MEP_OPERAND_SIMM8, (long *) (& fields->f_8s8));
      break;
    case MEP_OPERAND_SP :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_SPR :
      errmsg = parse_spreg (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_TP :
      errmsg = cgen_parse_keyword (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_TPR :
      errmsg = parse_tpreg (cd, strp, & mep_cgen_opval_h_gpr, & junk);
      break;
    case MEP_OPERAND_UDISP2 :
      errmsg = cgen_parse_signed_integer (cd, strp, MEP_OPERAND_UDISP2, (long *) (& fields->f_2u6));
      break;
    case MEP_OPERAND_UDISP7 :
      errmsg = parse_unsigned7 (cd, strp, MEP_OPERAND_UDISP7, (unsigned long *) (& fields->f_7u9));
      break;
    case MEP_OPERAND_UDISP7A2 :
      errmsg = parse_unsigned7 (cd, strp, MEP_OPERAND_UDISP7A2, (unsigned long *) (& fields->f_7u9a2));
      break;
    case MEP_OPERAND_UDISP7A4 :
      errmsg = parse_unsigned7 (cd, strp, MEP_OPERAND_UDISP7A4, (unsigned long *) (& fields->f_7u9a4));
      break;
    case MEP_OPERAND_UIMM16 :
      errmsg = parse_unsigned16 (cd, strp, MEP_OPERAND_UIMM16, (unsigned long *) (& fields->f_16u16));
      break;
    case MEP_OPERAND_UIMM2 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_UIMM2, (unsigned long *) (& fields->f_2u10));
      break;
    case MEP_OPERAND_UIMM24 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_UIMM24, (unsigned long *) (& fields->f_24u8n));
      break;
    case MEP_OPERAND_UIMM3 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_UIMM3, (unsigned long *) (& fields->f_3u5));
      break;
    case MEP_OPERAND_UIMM4 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_UIMM4, (unsigned long *) (& fields->f_4u8));
      break;
    case MEP_OPERAND_UIMM5 :
      errmsg = cgen_parse_unsigned_integer (cd, strp, MEP_OPERAND_UIMM5, (unsigned long *) (& fields->f_5u8));
      break;
    case MEP_OPERAND_UIMM7A4 :
      errmsg = parse_mep_alignu (cd, strp, MEP_OPERAND_UIMM7A4, (unsigned long *) (& fields->f_7u9a4));
      break;
    case MEP_OPERAND_ZERO :
      errmsg = parse_zero (cd, strp, MEP_OPERAND_ZERO, (long *) (& junk));
      break;

    default :
      /* xgettext:c-format */
      fprintf (stderr, _("Unrecognized field %d while parsing.\n"), opindex);
      abort ();
  }

  return errmsg;
}

cgen_parse_fn * const mep_cgen_parse_handlers[] = 
{
  parse_insn_normal,
};

void
mep_cgen_init_asm (CGEN_CPU_DESC cd)
{
  mep_cgen_init_opcode_table (cd);
  mep_cgen_init_ibld_table (cd);
  cd->parse_handlers = & mep_cgen_parse_handlers[0];
  cd->parse_operand = mep_cgen_parse_operand;
#ifdef CGEN_ASM_INIT_HOOK
CGEN_ASM_INIT_HOOK
#endif
}



/* Regex construction routine.

   This translates an opcode syntax string into a regex string,
   by replacing any non-character syntax element (such as an
   opcode) with the pattern '.*'

   It then compiles the regex and stores it in the opcode, for
   later use by mep_cgen_assemble_insn

   Returns NULL for success, an error message for failure.  */

char * 
mep_cgen_build_insn_regex (CGEN_INSN *insn)
{  
  CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
  const char *mnem = CGEN_INSN_MNEMONIC (insn);
  char rxbuf[CGEN_MAX_RX_ELEMENTS];
  char *rx = rxbuf;
  const CGEN_SYNTAX_CHAR_TYPE *syn;
  int reg_err;

  syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));

  /* Mnemonics come first in the syntax string.  */
  if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
    return _("missing mnemonic in syntax string");
  ++syn;

  /* Generate a case sensitive regular expression that emulates case
     insensitive matching in the "C" locale.  We cannot generate a case
     insensitive regular expression because in Turkish locales, 'i' and 'I'
     are not equal modulo case conversion.  */

  /* Copy the literal mnemonic out of the insn.  */
  for (; *mnem; mnem++)
    {
      char c = *mnem;

      if (ISALPHA (c))
	{
	  *rx++ = '[';
	  *rx++ = TOLOWER (c);
	  *rx++ = TOUPPER (c);
	  *rx++ = ']';
	}
      else
	*rx++ = c;
    }

  /* Copy any remaining literals from the syntax string into the rx.  */
  for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
    {
      if (CGEN_SYNTAX_CHAR_P (* syn)) 
	{
	  char c = CGEN_SYNTAX_CHAR (* syn);

	  switch (c) 
	    {
	      /* Escape any regex metacharacters in the syntax.  */
	    case '.': case '[': case '\\': 
	    case '*': case '^': case '$': 

#ifdef CGEN_ESCAPE_EXTENDED_REGEX
	    case '?': case '{': case '}': 
	    case '(': case ')': case '*':
	    case '|': case '+': case ']':
#endif
	      *rx++ = '\\';
	      *rx++ = c;
	      break;

	    default:
	      if (ISALPHA (c))
		{
		  *rx++ = '[';
		  *rx++ = TOLOWER (c);
		  *rx++ = TOUPPER (c);
		  *rx++ = ']';
		}
	      else
		*rx++ = c;
	      break;
	    }
	}
      else
	{
	  /* Replace non-syntax fields with globs.  */
	  *rx++ = '.';
	  *rx++ = '*';
	}
    }

  /* Trailing whitespace ok.  */
  * rx++ = '['; 
  * rx++ = ' '; 
  * rx++ = '\t'; 
  * rx++ = ']'; 
  * rx++ = '*'; 

  /* But anchor it after that.  */
  * rx++ = '$'; 
  * rx = '\0';

  CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
  reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);

  if (reg_err == 0) 
    return NULL;
  else
    {
      static char msg[80];

      regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
      regfree ((regex_t *) CGEN_INSN_RX (insn));
      free (CGEN_INSN_RX (insn));
      (CGEN_INSN_RX (insn)) = NULL;
      return msg;
    }
}


/* Default insn parser.

   The syntax string is scanned and operands are parsed and stored in FIELDS.
   Relocs are queued as we go via other callbacks.

   ??? Note that this is currently an all-or-nothing parser.  If we fail to
   parse the instruction, we return 0 and the caller will start over from
   the beginning.  Backtracking will be necessary in parsing subexpressions,
   but that can be handled there.  Not handling backtracking here may get
   expensive in the case of the m68k.  Deal with later.

   Returns NULL for success, an error message for failure.  */

static const char *
parse_insn_normal (CGEN_CPU_DESC cd,
		   const CGEN_INSN *insn,
		   const char **strp,
		   CGEN_FIELDS *fields)
{
  /* ??? Runtime added insns not handled yet.  */
  const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
  const char *str = *strp;
  const char *errmsg;
  const char *p;
  const CGEN_SYNTAX_CHAR_TYPE * syn;
#ifdef CGEN_MNEMONIC_OPERANDS
  /* FIXME: wip */
  int past_opcode_p;
#endif

  /* For now we assume the mnemonic is first (there are no leading operands).
     We can parse it without needing to set up operand parsing.
     GAS's input scrubber will ensure mnemonics are lowercase, but we may
     not be called from GAS.  */
  p = CGEN_INSN_MNEMONIC (insn);
  while (*p && TOLOWER (*p) == TOLOWER (*str))
    ++p, ++str;

  if (* p)
    return _("unrecognized instruction");

#ifndef CGEN_MNEMONIC_OPERANDS
  if (* str && ! ISSPACE (* str))
    return _("unrecognized instruction");
#endif

  CGEN_INIT_PARSE (cd);
  cgen_init_parse_operand (cd);
#ifdef CGEN_MNEMONIC_OPERANDS
  past_opcode_p = 0;
#endif

  /* We don't check for (*str != '\0') here because we want to parse
     any trailing fake arguments in the syntax string.  */
  syn = CGEN_SYNTAX_STRING (syntax);

  /* Mnemonics come first for now, ensure valid string.  */
  if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
    abort ();

  ++syn;

  while (* syn != 0)
    {
      /* Non operand chars must match exactly.  */
      if (CGEN_SYNTAX_CHAR_P (* syn))
	{
	  /* FIXME: While we allow for non-GAS callers above, we assume the
	     first char after the mnemonic part is a space.  */
	  /* FIXME: We also take inappropriate advantage of the fact that
	     GAS's input scrubber will remove extraneous blanks.  */
	  if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
	    {
#ifdef CGEN_MNEMONIC_OPERANDS
	      if (CGEN_SYNTAX_CHAR(* syn) == ' ')
		past_opcode_p = 1;
#endif
	      ++ syn;
	      ++ str;
	    }
	  else if (*str)
	    {
	      /* Syntax char didn't match.  Can't be this insn.  */
	      static char msg [80];

	      /* xgettext:c-format */
	      sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
		       CGEN_SYNTAX_CHAR(*syn), *str);
	      return msg;
	    }
	  else
	    {
	      /* Ran out of input.  */
	      static char msg [80];

	      /* xgettext:c-format */
	      sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
		       CGEN_SYNTAX_CHAR(*syn));
	      return msg;
	    }
	  continue;
	}

      /* We have an operand of some sort.  */
      errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn),
					  &str, fields);
      if (errmsg)
	return errmsg;

      /* Done with this operand, continue with next one.  */
      ++ syn;
    }

  /* If we're at the end of the syntax string, we're done.  */
  if (* syn == 0)
    {
      /* FIXME: For the moment we assume a valid `str' can only contain
	 blanks now.  IE: We needn't try again with a longer version of
	 the insn and it is assumed that longer versions of insns appear
	 before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
      while (ISSPACE (* str))
	++ str;

      if (* str != '\0')
	return _("junk at end of line"); /* FIXME: would like to include `str' */

      return NULL;
    }

  /* We couldn't parse it.  */
  return _("unrecognized instruction");
}

/* Main entry point.
   This routine is called for each instruction to be assembled.
   STR points to the insn to be assembled.
   We assume all necessary tables have been initialized.
   The assembled instruction, less any fixups, is stored in BUF.
   Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
   still needs to be converted to target byte order, otherwise BUF is an array
   of bytes in target byte order.
   The result is a pointer to the insn's entry in the opcode table,
   or NULL if an error occured (an error message will have already been
   printed).

   Note that when processing (non-alias) macro-insns,
   this function recurses.

   ??? It's possible to make this cpu-independent.
   One would have to deal with a few minor things.
   At this point in time doing so would be more of a curiosity than useful
   [for example this file isn't _that_ big], but keeping the possibility in
   mind helps keep the design clean.  */

const CGEN_INSN *
mep_cgen_assemble_insn (CGEN_CPU_DESC cd,
			   const char *str,
			   CGEN_FIELDS *fields,
			   CGEN_INSN_BYTES_PTR buf,
			   char **errmsg)
{
  const char *start;
  CGEN_INSN_LIST *ilist;
  const char *parse_errmsg = NULL;
  const char *insert_errmsg = NULL;
  int recognized_mnemonic = 0;

  /* Skip leading white space.  */
  while (ISSPACE (* str))
    ++ str;

  /* The instructions are stored in hashed lists.
     Get the first in the list.  */
  ilist = CGEN_ASM_LOOKUP_INSN (cd, str);

  /* Keep looking until we find a match.  */
  start = str;
  for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
    {
      const CGEN_INSN *insn = ilist->insn;
      recognized_mnemonic = 1;

#ifdef CGEN_VALIDATE_INSN_SUPPORTED 
      /* Not usually needed as unsupported opcodes
	 shouldn't be in the hash lists.  */
      /* Is this insn supported by the selected cpu?  */
      if (! mep_cgen_insn_supported (cd, insn))
	continue;
#endif
      /* If the RELAXED attribute is set, this is an insn that shouldn't be
	 chosen immediately.  Instead, it is used during assembler/linker
	 relaxation if possible.  */
      if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
	continue;

      str = start;

      /* Skip this insn if str doesn't look right lexically.  */
      if (CGEN_INSN_RX (insn) != NULL &&
	  regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
	continue;

      /* Allow parse/insert handlers to obtain length of insn.  */
      CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);

      parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
      if (parse_errmsg != NULL)
	continue;

      /* ??? 0 is passed for `pc'.  */
      insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
						 (bfd_vma) 0);
      if (insert_errmsg != NULL)
        continue;

      /* It is up to the caller to actually output the insn and any
         queued relocs.  */
      return insn;
    }

  {
    static char errbuf[150];
#ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
    const char *tmp_errmsg;

    /* If requesting verbose error messages, use insert_errmsg.
       Failing that, use parse_errmsg.  */
    tmp_errmsg = (insert_errmsg ? insert_errmsg :
		  parse_errmsg ? parse_errmsg :
		  recognized_mnemonic ?
		  _("unrecognized form of instruction") :
		  _("unrecognized instruction"));

    if (strlen (start) > 50)
      /* xgettext:c-format */
      sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
    else 
      /* xgettext:c-format */
      sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
#else
    if (strlen (start) > 50)
      /* xgettext:c-format */
      sprintf (errbuf, _("bad instruction `%.50s...'"), start);
    else 
      /* xgettext:c-format */
      sprintf (errbuf, _("bad instruction `%.50s'"), start);
#endif
      
    *errmsg = errbuf;
    return NULL;
  }
}