aboutsummaryrefslogtreecommitdiff
path: root/gas/config/tc-avr.c
blob: 34565b7de40456de0435ec621830e984045a55d6 (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
/* tc-avr.c -- Assembler code for the ATMEL AVR

   Copyright 1999, 2000, 2001, 2002, 2004, 2005
   Free Software Foundation, Inc.
   Contributed by Denis Chertykov <denisc@overta.ru>

   This file is part of GAS, the GNU Assembler.

   GAS 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, or (at your option)
   any later version.

   GAS 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 GAS; see the file COPYING.  If not, write to
   the Free Software Foundation, 51 Franklin Street - Fifth Floor,
   Boston, MA 02110-1301, USA.  */

#include <stdio.h>
#include "as.h"
#include "safe-ctype.h"
#include "subsegs.h"

struct avr_opcodes_s
{
  char *name;
  char *constraints;
  int insn_size;		/* In words.  */
  int isa;
  unsigned int bin_opcode;
};

#define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
{#NAME, CONSTR, SIZE, ISA, BIN},

struct avr_opcodes_s avr_opcodes[] =
{
  #include "opcode/avr.h"
  {NULL, NULL, 0, 0, 0}
};

const char comment_chars[] = ";";
const char line_comment_chars[] = "#";
const char line_separator_chars[] = "$";

const char *md_shortopts = "m:";
struct mcu_type_s
{
  char *name;
  int isa;
  int mach;
};

/* XXX - devices that don't seem to exist (renamed, replaced with larger
   ones, or planned but never produced), left here for compatibility.
   TODO: hide them in show_mcu_list output?  */

static struct mcu_type_s mcu_types[] =
{
  {"avr1",      AVR_ISA_TINY1,    bfd_mach_avr1},
  {"avr2",      AVR_ISA_TINY2,    bfd_mach_avr2},
  {"avr3",      AVR_ISA_M103,     bfd_mach_avr3},
  {"avr4",      AVR_ISA_M8,       bfd_mach_avr4},
  {"avr5",      AVR_ISA_ALL,      bfd_mach_avr5},
  {"at90s1200", AVR_ISA_1200,     bfd_mach_avr1},
  {"attiny10",  AVR_ISA_TINY1,    bfd_mach_avr1}, /* XXX -> tn11 */
  {"attiny11",  AVR_ISA_TINY1,    bfd_mach_avr1},
  {"attiny12",  AVR_ISA_TINY1,    bfd_mach_avr1},
  {"attiny15",  AVR_ISA_TINY1,    bfd_mach_avr1},
  {"attiny28",  AVR_ISA_TINY1,    bfd_mach_avr1},
  {"at90s2313", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90s2323", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90s2333", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 4433 */
  {"at90s2343", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"attiny22",  AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 2343 */
  {"attiny26",  AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90s4433", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90s4414", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 8515 */
  {"at90s4434", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 8535 */
  {"at90s8515", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90s8535", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at90c8534", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"at86rf401", AVR_ISA_2xxx,     bfd_mach_avr2},
  {"attiny13",  AVR_ISA_TINY2,    bfd_mach_avr2},
  {"attiny2313",AVR_ISA_TINY2,    bfd_mach_avr2},
  {"atmega603", AVR_ISA_M603,     bfd_mach_avr3}, /* XXX -> m103 */
  {"atmega103", AVR_ISA_M103,     bfd_mach_avr3},
  {"at43usb320",AVR_ISA_M103,     bfd_mach_avr3},
  {"at43usb355",AVR_ISA_M603,     bfd_mach_avr3},
  {"at76c711",  AVR_ISA_M603,     bfd_mach_avr3},
  {"atmega48",  AVR_ISA_M8,       bfd_mach_avr4},
  {"atmega8",   AVR_ISA_M8,       bfd_mach_avr4},
  {"atmega83",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8535 */
  {"atmega85",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8 */
  {"atmega88",  AVR_ISA_M8,       bfd_mach_avr4},
  {"atmega8515",AVR_ISA_M8,       bfd_mach_avr4},
  {"atmega8535",AVR_ISA_M8,       bfd_mach_avr4},
  {"atmega16",  AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega161", AVR_ISA_M161,     bfd_mach_avr5},
  {"atmega162", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega163", AVR_ISA_M161,     bfd_mach_avr5},
  {"atmega165", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega168", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega169", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega32",  AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega323", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega325", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega3250",AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega64",  AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega128", AVR_ISA_M128,     bfd_mach_avr5},
  {"atmega645", AVR_ISA_M323,     bfd_mach_avr5},
  {"atmega6450",AVR_ISA_M323,     bfd_mach_avr5},
  {"at90can128",AVR_ISA_M128,     bfd_mach_avr5},
  {"at94k",     AVR_ISA_94K,      bfd_mach_avr5},
  {NULL, 0, 0}
};

/* Current MCU type.  */
static struct mcu_type_s default_mcu = {"avr2", AVR_ISA_2xxx,bfd_mach_avr2};
static struct mcu_type_s *avr_mcu = &default_mcu;

/* AVR target-specific switches.  */
struct avr_opt_s
{
  int all_opcodes;  /* -mall-opcodes: accept all known AVR opcodes  */
  int no_skip_bug;  /* -mno-skip-bug: no warnings for skipping 2-word insns  */
  int no_wrap;      /* -mno-wrap: reject rjmp/rcall with 8K wrap-around  */
};

static struct avr_opt_s avr_opt = { 0, 0, 0 };

const char EXP_CHARS[] = "eE";
const char FLT_CHARS[] = "dD";
static void avr_set_arch (int dummy);

/* The target specific pseudo-ops which we support.  */
const pseudo_typeS md_pseudo_table[] =
{
  {"arch", avr_set_arch,	0},
  { NULL,	NULL,		0}
};

#define LDI_IMMEDIATE(x) (((x) & 0xf) | (((x) << 4) & 0xf00))

static void show_mcu_list PARAMS ((FILE *));
static char *skip_space PARAMS ((char *));
static char *extract_word PARAMS ((char *, char *, int));
static unsigned int avr_operand PARAMS ((struct avr_opcodes_s *,
					 int, char *, char **));
static unsigned int avr_operands PARAMS ((struct avr_opcodes_s *, char **));
static unsigned int avr_get_constant PARAMS ((char *, int));
static char *parse_exp PARAMS ((char *, expressionS *));
static bfd_reloc_code_real_type avr_ldi_expression PARAMS ((expressionS *));

#define EXP_MOD_NAME(i) exp_mod[i].name
#define EXP_MOD_RELOC(i) exp_mod[i].reloc
#define EXP_MOD_NEG_RELOC(i) exp_mod[i].neg_reloc
#define HAVE_PM_P(i) exp_mod[i].have_pm

struct exp_mod_s
{
  char *name;
  bfd_reloc_code_real_type reloc;
  bfd_reloc_code_real_type neg_reloc;
  int have_pm;
};

static struct exp_mod_s exp_mod[] =
{
  {"hh8",    BFD_RELOC_AVR_HH8_LDI,    BFD_RELOC_AVR_HH8_LDI_NEG,    1},
  {"pm_hh8", BFD_RELOC_AVR_HH8_LDI_PM, BFD_RELOC_AVR_HH8_LDI_PM_NEG, 0},
  {"hi8",    BFD_RELOC_AVR_HI8_LDI,    BFD_RELOC_AVR_HI8_LDI_NEG,    1},
  {"pm_hi8", BFD_RELOC_AVR_HI8_LDI_PM, BFD_RELOC_AVR_HI8_LDI_PM_NEG, 0},
  {"lo8",    BFD_RELOC_AVR_LO8_LDI,    BFD_RELOC_AVR_LO8_LDI_NEG,    1},
  {"pm_lo8", BFD_RELOC_AVR_LO8_LDI_PM, BFD_RELOC_AVR_LO8_LDI_PM_NEG, 0},
  {"hlo8",   -BFD_RELOC_AVR_LO8_LDI,   -BFD_RELOC_AVR_LO8_LDI_NEG,   0},
  {"hhi8",   -BFD_RELOC_AVR_HI8_LDI,   -BFD_RELOC_AVR_HI8_LDI_NEG,   0},
};

/* Opcode hash table.  */
static struct hash_control *avr_hash;

/* Reloc modifiers hash control (hh8,hi8,lo8,pm_xx).  */
static struct hash_control *avr_mod_hash;

#define OPTION_MMCU 'm'
#define OPTION_ALL_OPCODES (OPTION_MD_BASE + 1)
#define OPTION_NO_SKIP_BUG (OPTION_MD_BASE + 2)
#define OPTION_NO_WRAP     (OPTION_MD_BASE + 3)

struct option md_longopts[] =
{
  { "mmcu",   required_argument, NULL, OPTION_MMCU        },
  { "mall-opcodes", no_argument, NULL, OPTION_ALL_OPCODES },
  { "mno-skip-bug", no_argument, NULL, OPTION_NO_SKIP_BUG },
  { "mno-wrap",     no_argument, NULL, OPTION_NO_WRAP     },
  { NULL, no_argument, NULL, 0 }
};

size_t md_longopts_size = sizeof (md_longopts);

/* Display nicely formatted list of known MCU names.  */

static void
show_mcu_list (stream)
     FILE *stream;
{
  int i, x;

  fprintf (stream, _("Known MCU names:"));
  x = 1000;

  for (i = 0; mcu_types[i].name; i++)
    {
      int len = strlen (mcu_types[i].name);

      x += len + 1;

      if (x < 75)
	fprintf (stream, " %s", mcu_types[i].name);
      else
	{
	  fprintf (stream, "\n  %s", mcu_types[i].name);
	  x = len + 2;
	}
    }

  fprintf (stream, "\n");
}

static inline char *
skip_space (s)
     char *s;
{
  while (*s == ' ' || *s == '\t')
    ++s;
  return s;
}

/* Extract one word from FROM and copy it to TO.  */

static char *
extract_word (char *from, char *to, int limit)
{
  char *op_start;
  char *op_end;
  int size = 0;

  /* Drop leading whitespace.  */
  from = skip_space (from);
  *to = 0;

  /* Find the op code end.  */
  for (op_start = op_end = from; *op_end != 0 && is_part_of_name (*op_end);)
    {
      to[size++] = *op_end++;
      if (size + 1 >= limit)
	break;
    }

  to[size] = 0;
  return op_end;
}

int
md_estimate_size_before_relax (fragp, seg)
     fragS *fragp ATTRIBUTE_UNUSED;
     asection *seg ATTRIBUTE_UNUSED;
{
  abort ();
  return 0;
}

void
md_show_usage (stream)
     FILE *stream;
{
  fprintf (stream,
      _("AVR options:\n"
	"  -mmcu=[avr-name] select microcontroller variant\n"
	"                   [avr-name] can be:\n"
	"                   avr1 - AT90S1200, ATtiny1x, ATtiny28\n"
	"                   avr2 - AT90S2xxx, AT90S4xxx, AT90S8xxx, ATtiny22\n"
	"                   avr3 - ATmega103, ATmega603\n"
	"                   avr4 - ATmega83, ATmega85\n"
	"                   avr5 - ATmega161, ATmega163, ATmega32, AT94K\n"
	"                   or immediate microcontroller name.\n"));
  fprintf (stream,
      _("  -mall-opcodes    accept all AVR opcodes, even if not supported by MCU\n"
	"  -mno-skip-bug    disable warnings for skipping two-word instructions\n"
	"                   (default for avr4, avr5)\n"
	"  -mno-wrap        reject rjmp/rcall instructions with 8K wrap-around\n"
	"                   (default for avr3, avr5)\n"));
  show_mcu_list (stream);
}

static void
avr_set_arch (dummy)
     int dummy ATTRIBUTE_UNUSED;
{
  char *str;

  str = (char *) alloca (20);
  input_line_pointer = extract_word (input_line_pointer, str, 20);
  md_parse_option (OPTION_MMCU, str);
  bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
}

int
md_parse_option (c, arg)
     int c;
     char *arg;
{
  switch (c)
    {
    case OPTION_MMCU:
      {
	int i;
	char *s = alloca (strlen (arg) + 1);

	{
	  char *t = s;
	  char *arg1 = arg;

	  do
	    *t = TOLOWER (*arg1++);
	  while (*t++);
	}

	for (i = 0; mcu_types[i].name; ++i)
	  if (strcmp (mcu_types[i].name, s) == 0)
	    break;

	if (!mcu_types[i].name)
	  {
	    show_mcu_list (stderr);
	    as_fatal (_("unknown MCU: %s\n"), arg);
	  }

	/* It is OK to redefine mcu type within the same avr[1-5] bfd machine
	   type - this for allows passing -mmcu=... via gcc ASM_SPEC as well
	   as .arch ... in the asm output at the same time.  */
	if (avr_mcu == &default_mcu || avr_mcu->mach == mcu_types[i].mach)
	  avr_mcu = &mcu_types[i];
	else
	  as_fatal (_("redefinition of mcu type `%s' to `%s'"),
		    avr_mcu->name, mcu_types[i].name);
	return 1;
      }
    case OPTION_ALL_OPCODES:
      avr_opt.all_opcodes = 1;
      return 1;
    case OPTION_NO_SKIP_BUG:
      avr_opt.no_skip_bug = 1;
      return 1;
    case OPTION_NO_WRAP:
      avr_opt.no_wrap = 1;
      return 1;
    }

  return 0;
}

symbolS *
md_undefined_symbol (name)
     char *name ATTRIBUTE_UNUSED;
{
  return 0;
}

/* Turn a string in input_line_pointer into a floating point constant
   of type TYPE, and store the appropriate bytes in *LITP.  The number
   of LITTLENUMS emitted is stored in *SIZEP.  An error message is
   returned, or NULL on OK.  */

char *
md_atof (type, litP, sizeP)
     int type;
     char *litP;
     int *sizeP;
{
  int prec;
  LITTLENUM_TYPE words[4];
  LITTLENUM_TYPE *wordP;
  char *t;

  switch (type)
    {
    case 'f':
      prec = 2;
      break;
    case 'd':
      prec = 4;
      break;
    default:
      *sizeP = 0;
      return _("bad call to md_atof");
    }

  t = atof_ieee (input_line_pointer, type, words);
  if (t)
    input_line_pointer = t;

  *sizeP = prec * sizeof (LITTLENUM_TYPE);

  /* This loop outputs the LITTLENUMs in REVERSE order.  */
  for (wordP = words + prec - 1; prec--;)
    {
      md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
      litP += sizeof (LITTLENUM_TYPE);
    }

  return NULL;
}

void
md_convert_frag (abfd, sec, fragP)
     bfd *abfd ATTRIBUTE_UNUSED;
     asection *sec ATTRIBUTE_UNUSED;
     fragS *fragP ATTRIBUTE_UNUSED;
{
  abort ();
}

void
md_begin ()
{
  unsigned int i;
  struct avr_opcodes_s *opcode;
  avr_hash = hash_new ();

  /* Insert unique names into hash table.  This hash table then provides a
     quick index to the first opcode with a particular name in the opcode
     table.  */
  for (opcode = avr_opcodes; opcode->name; opcode++)
    hash_insert (avr_hash, opcode->name, (char *) opcode);

  avr_mod_hash = hash_new ();

  for (i = 0; i < sizeof (exp_mod) / sizeof (exp_mod[0]); ++i)
    hash_insert (avr_mod_hash, EXP_MOD_NAME (i), (void *) (i + 10));

  bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
}

/* Resolve STR as a constant expression and return the result.
   If result greater than MAX then error.  */

static unsigned int
avr_get_constant (str, max)
     char *str;
     int max;
{
  expressionS ex;
  str = skip_space (str);
  input_line_pointer = str;
  expression (&ex);

  if (ex.X_op != O_constant)
    as_bad (_("constant value required"));

  if (ex.X_add_number > max || ex.X_add_number < 0)
    as_bad (_("number must be less than %d"), max + 1);

  return ex.X_add_number;
}

/* Parse instruction operands.
   Return binary opcode.  */

static unsigned int
avr_operands (opcode, line)
     struct avr_opcodes_s *opcode;
     char **line;
{
  char *op = opcode->constraints;
  unsigned int bin = opcode->bin_opcode;
  char *frag = frag_more (opcode->insn_size * 2);
  char *str = *line;
  int where = frag - frag_now->fr_literal;
  static unsigned int prev = 0;  /* Previous opcode.  */

  /* Opcode have operands.  */
  if (*op)
    {
      unsigned int reg1 = 0;
      unsigned int reg2 = 0;
      int reg1_present = 0;
      int reg2_present = 0;

      /* Parse first operand.  */
      if (REGISTER_P (*op))
	reg1_present = 1;
      reg1 = avr_operand (opcode, where, op, &str);
      ++op;

      /* Parse second operand.  */
      if (*op)
	{
	  if (*op == ',')
	    ++op;

	  if (*op == '=')
	    {
	      reg2 = reg1;
	      reg2_present = 1;
	    }
	  else
	    {
	      if (REGISTER_P (*op))
		reg2_present = 1;

	      str = skip_space (str);
	      if (*str++ != ',')
		as_bad (_("`,' required"));
	      str = skip_space (str);

	      reg2 = avr_operand (opcode, where, op, &str);

	    }

	  if (reg1_present && reg2_present)
	    reg2 = (reg2 & 0xf) | ((reg2 << 5) & 0x200);
	  else if (reg2_present)
	    reg2 <<= 4;
	}
      if (reg1_present)
	reg1 <<= 4;
      bin |= reg1 | reg2;
    }

  /* Detect undefined combinations (like ld r31,Z+).  */
  if (!avr_opt.all_opcodes && AVR_UNDEF_P (bin))
    as_warn (_("undefined combination of operands"));

  if (opcode->insn_size == 2)
    {
      /* Warn if the previous opcode was cpse/sbic/sbis/sbrc/sbrs
         (AVR core bug, fixed in the newer devices).  */

      if (!(avr_opt.no_skip_bug ||
            (avr_mcu->isa & (AVR_ISA_MUL | AVR_ISA_MOVW)))
	  && AVR_SKIP_P (prev))
	as_warn (_("skipping two-word instruction"));

      bfd_putl32 ((bfd_vma) bin, frag);
    }
  else
    bfd_putl16 ((bfd_vma) bin, frag);

  prev = bin;
  *line = str;
  return bin;
}

/* Parse for ldd/std offset */

static void
avr_offset_expression (expressionS *exp)
{
  char *str = input_line_pointer;
  char *tmp;
  char op[8];

  tmp = str;
  str = extract_word (str, op, sizeof (op));

  input_line_pointer = tmp;
  expression (exp);

  /* Warn about expressions that fail to use lo8 ().  */
  if (exp->X_op == O_constant)
    {
      int x = exp->X_add_number;
      
      if (x < -255 || x > 255)
	as_warn (_("constant out of 8-bit range: %d"), x);
    }
}

/* Parse one instruction operand.
   Return operand bitmask.  Also fixups can be generated.  */

static unsigned int
avr_operand (opcode, where, op, line)
     struct avr_opcodes_s *opcode;
     int where;
     char *op;
     char **line;
{
  expressionS op_expr;
  unsigned int op_mask = 0;
  char *str = skip_space (*line);

  switch (*op)
    {
      /* Any register operand.  */
    case 'w':
    case 'd':
    case 'r':
    case 'a':
    case 'v':
      if (*str == 'r' || *str == 'R')
	{
	  char r_name[20];

	  str = extract_word (str, r_name, sizeof (r_name));
	  op_mask = 0xff;
	  if (ISDIGIT (r_name[1]))
	    {
	      if (r_name[2] == '\0')
		op_mask = r_name[1] - '0';
	      else if (r_name[1] != '0'
		       && ISDIGIT (r_name[2])
		       && r_name[3] == '\0')
		op_mask = (r_name[1] - '0') * 10 + r_name[2] - '0';
	    }
	}
      else
	{
	  op_mask = avr_get_constant (str, 31);
	  str = input_line_pointer;
	}

      if (op_mask <= 31)
	{
	  switch (*op)
	    {
	    case 'a':
	      if (op_mask < 16 || op_mask > 23)
		as_bad (_("register r16-r23 required"));
	      op_mask -= 16;
	      break;

	    case 'd':
	      if (op_mask < 16)
		as_bad (_("register number above 15 required"));
	      op_mask -= 16;
	      break;

	    case 'v':
	      if (op_mask & 1)
		as_bad (_("even register number required"));
	      op_mask >>= 1;
	      break;

	    case 'w':
	      if ((op_mask & 1) || op_mask < 24)
		as_bad (_("register r24, r26, r28 or r30 required"));
	      op_mask = (op_mask - 24) >> 1;
	      break;
	    }
	  break;
	}
      as_bad (_("register name or number from 0 to 31 required"));
      break;

    case 'e':
      {
	char c;

	if (*str == '-')
	  {
	    str = skip_space (str + 1);
	    op_mask = 0x1002;
	  }
	c = TOLOWER (*str);
	if (c == 'x')
	  op_mask |= 0x100c;
	else if (c == 'y')
	  op_mask |= 0x8;
	else if (c != 'z')
	  as_bad (_("pointer register (X, Y or Z) required"));

	str = skip_space (str + 1);
	if (*str == '+')
	  {
	    ++str;
	    if (op_mask & 2)
	      as_bad (_("cannot both predecrement and postincrement"));
	    op_mask |= 0x1001;
	  }

	/* avr1 can do "ld r,Z" and "st Z,r" but no other pointer
	   registers, no predecrement, no postincrement.  */
	if (!avr_opt.all_opcodes && (op_mask & 0x100F)
	    && !(avr_mcu->isa & AVR_ISA_SRAM))
	  as_bad (_("addressing mode not supported"));
      }
      break;

    case 'z':
      if (*str == '-')
	as_bad (_("can't predecrement"));

      if (! (*str == 'z' || *str == 'Z'))
	as_bad (_("pointer register Z required"));

      str = skip_space (str + 1);

      if (*str == '+')
	{
	  ++str;
	  op_mask |= 1;
	}
      break;

    case 'b':
      {
	char c = TOLOWER (*str++);

	if (c == 'y')
	  op_mask |= 0x8;
	else if (c != 'z')
	  as_bad (_("pointer register (Y or Z) required"));
	str = skip_space (str);
	if (*str++ == '+')
	  {
	    input_line_pointer = str;
	    avr_offset_expression (& op_expr);
	    str = input_line_pointer;
	    fix_new_exp (frag_now, where, 3,
			 &op_expr, FALSE, BFD_RELOC_AVR_6);
	  }
      }
      break;

    case 'h':
      str = parse_exp (str, &op_expr);
      fix_new_exp (frag_now, where, opcode->insn_size * 2,
		   &op_expr, FALSE, BFD_RELOC_AVR_CALL);
      break;

    case 'L':
      str = parse_exp (str, &op_expr);
      fix_new_exp (frag_now, where, opcode->insn_size * 2,
		   &op_expr, TRUE, BFD_RELOC_AVR_13_PCREL);
      break;

    case 'l':
      str = parse_exp (str, &op_expr);
      fix_new_exp (frag_now, where, opcode->insn_size * 2,
		   &op_expr, TRUE, BFD_RELOC_AVR_7_PCREL);
      break;

    case 'i':
      str = parse_exp (str, &op_expr);
      fix_new_exp (frag_now, where + 2, opcode->insn_size * 2,
		   &op_expr, FALSE, BFD_RELOC_16);
      break;

    case 'M':
      {
	bfd_reloc_code_real_type r_type;

	input_line_pointer = str;
	r_type = avr_ldi_expression (&op_expr);
	str = input_line_pointer;
	fix_new_exp (frag_now, where, 3,
		     &op_expr, FALSE, r_type);
      }
      break;

    case 'n':
      {
	unsigned int x;

	x = ~avr_get_constant (str, 255);
	str = input_line_pointer;
	op_mask |= (x & 0xf) | ((x << 4) & 0xf00);
      }
      break;

    case 'K':
      input_line_pointer = str;
      avr_offset_expression (& op_expr);
      str = input_line_pointer;
      fix_new_exp (frag_now, where, 3,
		   & op_expr, FALSE, BFD_RELOC_AVR_6_ADIW);
      break;

    case 'S':
    case 's':
      {
	unsigned int x;

	x = avr_get_constant (str, 7);
	str = input_line_pointer;
	if (*op == 'S')
	  x <<= 4;
	op_mask |= x;
      }
      break;

    case 'P':
      {
	unsigned int x;

	x = avr_get_constant (str, 63);
	str = input_line_pointer;
	op_mask |= (x & 0xf) | ((x & 0x30) << 5);
      }
      break;

    case 'p':
      {
	unsigned int x;

	x = avr_get_constant (str, 31);
	str = input_line_pointer;
	op_mask |= x << 3;
      }
      break;

    case '?':
      break;

    default:
      as_bad (_("unknown constraint `%c'"), *op);
    }

  *line = str;
  return op_mask;
}

/* GAS will call this function for each section at the end of the assembly,
   to permit the CPU backend to adjust the alignment of a section.  */

valueT
md_section_align (seg, addr)
     asection *seg;
     valueT addr;
{
  int align = bfd_get_section_alignment (stdoutput, seg);
  return ((addr + (1 << align) - 1) & (-1 << align));
}

/* If you define this macro, it should return the offset between the
   address of a PC relative fixup and the position from which the PC
   relative adjustment should be made.  On many processors, the base
   of a PC relative instruction is the next instruction, so this
   macro would return the length of an instruction.  */

long
md_pcrel_from_section (fixp, sec)
     fixS *fixp;
     segT sec;
{
  if (fixp->fx_addsy != (symbolS *) NULL
      && (!S_IS_DEFINED (fixp->fx_addsy)
	  || (S_GET_SEGMENT (fixp->fx_addsy) != sec)))
    return 0;

  return fixp->fx_frag->fr_address + fixp->fx_where;
}

/* GAS will call this for each fixup.  It should store the correct
   value in the object file.  */

void
md_apply_fix3 (fixP, valP, seg)
     fixS *fixP;
     valueT * valP;
     segT seg;
{
  unsigned char *where;
  unsigned long insn;
  long value = *valP;

  if (fixP->fx_addsy == (symbolS *) NULL)
    fixP->fx_done = 1;

  else if (fixP->fx_pcrel)
    {
      segT s = S_GET_SEGMENT (fixP->fx_addsy);

      if (s == seg || s == absolute_section)
	{
	  value += S_GET_VALUE (fixP->fx_addsy);
	  fixP->fx_done = 1;
	}
    }

  /* We don't actually support subtracting a symbol.  */
  if (fixP->fx_subsy != (symbolS *) NULL)
    as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex"));

  switch (fixP->fx_r_type)
    {
    default:
      fixP->fx_no_overflow = 1;
      break;
    case BFD_RELOC_AVR_7_PCREL:
    case BFD_RELOC_AVR_13_PCREL:
    case BFD_RELOC_32:
    case BFD_RELOC_16:
    case BFD_RELOC_AVR_CALL:
      break;
    }

  if (fixP->fx_done)
    {
      /* Fetch the instruction, insert the fully resolved operand
	 value, and stuff the instruction back again.  */
      where = (unsigned char *) fixP->fx_frag->fr_literal + fixP->fx_where;
      insn = bfd_getl16 (where);

      switch (fixP->fx_r_type)
	{
	case BFD_RELOC_AVR_7_PCREL:
	  if (value & 1)
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("odd address operand: %ld"), value);

	  /* Instruction addresses are always right-shifted by 1.  */
	  value >>= 1;
	  --value;			/* Correct PC.  */

	  if (value < -64 || value > 63)
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("operand out of range: %ld"), value);
	  value = (value << 3) & 0x3f8;
	  bfd_putl16 ((bfd_vma) (value | insn), where);
	  break;

	case BFD_RELOC_AVR_13_PCREL:
	  if (value & 1)
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("odd address operand: %ld"), value);

	  /* Instruction addresses are always right-shifted by 1.  */
	  value >>= 1;
	  --value;			/* Correct PC.  */

	  if (value < -2048 || value > 2047)
	    {
	      /* No wrap for devices with >8K of program memory.  */
	      if ((avr_mcu->isa & AVR_ISA_MEGA) || avr_opt.no_wrap)
		as_bad_where (fixP->fx_file, fixP->fx_line,
			      _("operand out of range: %ld"), value);
	    }

	  value &= 0xfff;
	  bfd_putl16 ((bfd_vma) (value | insn), where);
	  break;

	case BFD_RELOC_32:
	  bfd_putl16 ((bfd_vma) value, where);
	  break;

	case BFD_RELOC_16:
	  bfd_putl16 ((bfd_vma) value, where);
	  break;

	case BFD_RELOC_AVR_16_PM:
	  bfd_putl16 ((bfd_vma) (value >> 1), where);
	  break;

	case BFD_RELOC_AVR_LDI:
	  if (value > 255)
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("operand out of range: %ld"), value);
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
	  break;

	case BFD_RELOC_AVR_6:
	  if ((value > 63) || (value < 0))
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("operand out of range: %ld"), value);
	  bfd_putl16 ((bfd_vma) insn | ((value & 7) | ((value & (3 << 3)) << 7) | ((value & (1 << 5)) << 8)), where);
	  break;

	case BFD_RELOC_AVR_6_ADIW:
	  if ((value > 63) || (value < 0))
	    as_bad_where (fixP->fx_file, fixP->fx_line,
			  _("operand out of range: %ld"), value);
	  bfd_putl16 ((bfd_vma) insn | (value & 0xf) | ((value & 0x30) << 2), where);
	  break;

	case BFD_RELOC_AVR_LO8_LDI:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
	  break;

	case -BFD_RELOC_AVR_LO8_LDI:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
	  break;

	case BFD_RELOC_AVR_HI8_LDI:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 8), where);
	  break;

	case -BFD_RELOC_AVR_HI8_LDI:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 24), where);
	  break;

	case BFD_RELOC_AVR_HH8_LDI:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
	  break;

	case BFD_RELOC_AVR_LO8_LDI_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value), where);
	  break;

	case -BFD_RELOC_AVR_LO8_LDI_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
	  break;

	case BFD_RELOC_AVR_HI8_LDI_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 8), where);
	  break;

	case -BFD_RELOC_AVR_HI8_LDI_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 24), where);
	  break;

	case BFD_RELOC_AVR_HH8_LDI_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
	  break;

	case BFD_RELOC_AVR_LO8_LDI_PM:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 1), where);
	  break;

	case BFD_RELOC_AVR_HI8_LDI_PM:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 9), where);
	  break;

	case BFD_RELOC_AVR_HH8_LDI_PM:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 17), where);
	  break;

	case BFD_RELOC_AVR_LO8_LDI_PM_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 1), where);
	  break;

	case BFD_RELOC_AVR_HI8_LDI_PM_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 9), where);
	  break;

	case BFD_RELOC_AVR_HH8_LDI_PM_NEG:
	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 17), where);
	  break;

	case BFD_RELOC_AVR_CALL:
	  {
	    unsigned long x;

	    x = bfd_getl16 (where);
	    if (value & 1)
	      as_bad_where (fixP->fx_file, fixP->fx_line,
			    _("odd address operand: %ld"), value);
	    value >>= 1;
	    x |= ((value & 0x10000) | ((value << 3) & 0x1f00000)) >> 16;
	    bfd_putl16 ((bfd_vma) x, where);
	    bfd_putl16 ((bfd_vma) (value & 0xffff), where + 2);
	  }
	  break;

	default:
	  as_fatal (_("line %d: unknown relocation type: 0x%x"),
		    fixP->fx_line, fixP->fx_r_type);
	  break;
	}
    }
  else
    {
      switch (fixP->fx_r_type)
	{
	case -BFD_RELOC_AVR_HI8_LDI_NEG:
	case -BFD_RELOC_AVR_HI8_LDI:
	case -BFD_RELOC_AVR_LO8_LDI_NEG:
	case -BFD_RELOC_AVR_LO8_LDI:
	  as_bad_where (fixP->fx_file, fixP->fx_line,
			_("only constant expression allowed"));
	  fixP->fx_done = 1;
	  break;
	default:
	  break;
	}
    }
}

/* A `BFD_ASSEMBLER' GAS will call this to generate a reloc.  GAS
   will pass the resulting reloc to `bfd_install_relocation'.  This
   currently works poorly, as `bfd_install_relocation' often does the
   wrong thing, and instances of `tc_gen_reloc' have been written to
   work around the problems, which in turns makes it difficult to fix
   `bfd_install_relocation'.  */

/* If while processing a fixup, a reloc really needs to be created
   then it is done here.  */

arelent *
tc_gen_reloc (seg, fixp)
     asection *seg ATTRIBUTE_UNUSED;
     fixS *fixp;
{
  arelent *reloc;

  reloc = (arelent *) xmalloc (sizeof (arelent));

  reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
  *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);

  reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
  reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
  if (reloc->howto == (reloc_howto_type *) NULL)
    {
      as_bad_where (fixp->fx_file, fixp->fx_line,
		    _("reloc %d not supported by object file format"),
		    (int) fixp->fx_r_type);
      return NULL;
    }

  if (fixp->fx_r_type == BFD_RELOC_VTABLE_INHERIT
      || fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
    reloc->address = fixp->fx_offset;

  reloc->addend = fixp->fx_offset;

  return reloc;
}

void
md_assemble (str)
     char *str;
{
  struct avr_opcodes_s *opcode;
  char op[11];

  str = skip_space (extract_word (str, op, sizeof (op)));

  if (!op[0])
    as_bad (_("can't find opcode "));

  opcode = (struct avr_opcodes_s *) hash_find (avr_hash, op);

  if (opcode == NULL)
    {
      as_bad (_("unknown opcode `%s'"), op);
      return;
    }

  /* Special case for opcodes with optional operands (lpm, elpm) -
     version with operands exists in avr_opcodes[] in the next entry.  */

  if (*str && *opcode->constraints == '?')
    ++opcode;

  if (!avr_opt.all_opcodes && (opcode->isa & avr_mcu->isa) != opcode->isa)
    as_bad (_("illegal opcode %s for mcu %s"), opcode->name, avr_mcu->name);

  /* We used to set input_line_pointer to the result of get_operands,
     but that is wrong.  Our caller assumes we don't change it.  */
  {
    char *t = input_line_pointer;
    avr_operands (opcode, &str);
    if (*skip_space (str))
      as_bad (_("garbage at end of line"));
    input_line_pointer = t;
  }
}

/* Parse ordinary expression.  */

static char *
parse_exp (s, op)
     char *s;
     expressionS *op;
{
  input_line_pointer = s;
  expression (op);
  if (op->X_op == O_absent)
    as_bad (_("missing operand"));
  return input_line_pointer;
}

/* Parse special expressions (needed for LDI command):
   xx8 (address)
   xx8 (-address)
   pm_xx8 (address)
   pm_xx8 (-address)
   where xx is: hh, hi, lo.  */

static bfd_reloc_code_real_type
avr_ldi_expression (exp)
     expressionS *exp;
{
  char *str = input_line_pointer;
  char *tmp;
  char op[8];
  int mod;
  tmp = str;

  str = extract_word (str, op, sizeof (op));

  if (op[0])
    {
      mod = (int) hash_find (avr_mod_hash, op);

      if (mod)
	{
	  int closes = 0;

	  mod -= 10;
	  str = skip_space (str);

	  if (*str == '(')
	    {
	      int neg_p = 0;

	      ++str;

	      if (strncmp ("pm(", str, 3) == 0
		  || strncmp ("-(pm(", str, 5) == 0)
		{
		  if (HAVE_PM_P (mod))
		    {
		      ++mod;
		      ++closes;
		    }
		  else
		    as_bad (_("illegal expression"));

		  if (*str == '-')
		    {
		      neg_p = 1;
		      ++closes;
		      str += 5;
		    }
		  else
		    str += 3;
		}

	      if (*str == '-' && *(str + 1) == '(')
		{
		  neg_p ^= 1;
		  ++closes;
		  str += 2;
		}

	      input_line_pointer = str;
	      expression (exp);

	      do
		{
		  if (*input_line_pointer != ')')
		    {
		      as_bad (_("`)' required"));
		      break;
		    }
		  input_line_pointer++;
		}
	      while (closes--);

	      return neg_p ? EXP_MOD_NEG_RELOC (mod) : EXP_MOD_RELOC (mod);
	    }
	}
    }

  input_line_pointer = tmp;
  expression (exp);

  /* Warn about expressions that fail to use lo8 ().  */
  if (exp->X_op == O_constant)
    {
      int x = exp->X_add_number;
      if (x < -255 || x > 255)
	as_warn (_("constant out of 8-bit range: %d"), x);
    }

  return BFD_RELOC_AVR_LDI;
}

/* Flag to pass `pm' mode between `avr_parse_cons_expression' and
   `avr_cons_fix_new'.  */
static int exp_mod_pm = 0;

/* Parse special CONS expression: pm (expression)
   which is used for addressing to a program memory.
   Relocation: BFD_RELOC_AVR_16_PM.  */

void
avr_parse_cons_expression (exp, nbytes)
     expressionS *exp;
     int nbytes;
{
  char *tmp;

  exp_mod_pm = 0;

  tmp = input_line_pointer = skip_space (input_line_pointer);

  if (nbytes == 2)
    {
      char *pm_name = "pm";
      int len = strlen (pm_name);

      if (strncasecmp (input_line_pointer, pm_name, len) == 0)
	{
	  input_line_pointer = skip_space (input_line_pointer + len);

	  if (*input_line_pointer == '(')
	    {
	      input_line_pointer = skip_space (input_line_pointer + 1);
	      exp_mod_pm = 1;
	      expression (exp);

	      if (*input_line_pointer == ')')
		++input_line_pointer;
	      else
		{
		  as_bad (_("`)' required"));
		  exp_mod_pm = 0;
		}

	      return;
	    }

	  input_line_pointer = tmp;
	}
    }

  expression (exp);
}

void
avr_cons_fix_new (frag, where, nbytes, exp)
     fragS *frag;
     int where;
     int nbytes;
     expressionS *exp;
{
  if (exp_mod_pm == 0)
    {
      if (nbytes == 2)
	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_16);
      else if (nbytes == 4)
	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_32);
      else
	as_bad (_("illegal %srelocation size: %d"), "", nbytes);
    }
  else
    {
      if (nbytes == 2)
	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_AVR_16_PM);
      else
	as_bad (_("illegal %srelocation size: %d"), "`pm' ", nbytes);
      exp_mod_pm = 0;
    }
}