aboutsummaryrefslogtreecommitdiff
path: root/gdb/valops.c
blob: 83d6ec89c9367aafe33b9cf94a4d36f9609f2b09 (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
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
/* Perform non-arithmetic operations on values, for GDB.
   Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.

This file is part of GDB.

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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include <stdio.h>
#include "defs.h"
#include "symtab.h"
#include "value.h"
#include "frame.h"
#include "inferior.h"
#include "gdbcore.h"
#include "target.h"

#include <errno.h>

/* Local functions.  */
static value search_struct_field ();

/* Cast value ARG2 to type TYPE and return as a value.
   More general than a C cast: accepts any two types of the same length,
   and if ARG2 is an lvalue it can be cast into anything at all.  */
/* In C++, casts may change pointer representations.  */

value
value_cast (type, arg2)
     struct type *type;
     register value arg2;
{
  register enum type_code code1;
  register enum type_code code2;
  register int scalar;

  /* Coerce arrays but not enums.  Enums will work as-is
     and coercing them would cause an infinite recursion.  */
  if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_ENUM)
    COERCE_ARRAY (arg2);

  code1 = TYPE_CODE (type);
  code2 = TYPE_CODE (VALUE_TYPE (arg2));
  scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
	    || code2 == TYPE_CODE_ENUM);

  if (code1 == TYPE_CODE_FLT && scalar)
    return value_from_double (type, value_as_double (arg2));
  else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM)
	   && (scalar || code2 == TYPE_CODE_PTR))
    return value_from_longest (type, value_as_long (arg2));
  else if (TYPE_LENGTH (type) == TYPE_LENGTH (VALUE_TYPE (arg2)))
    {
      if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
	{
	  /* Look in the type of the source to see if it contains the
	     type of the target as a superclass.  If so, we'll need to
	     offset the pointer rather than just change its type.  */
	  struct type *t1 = TYPE_TARGET_TYPE (type);
	  struct type *t2 = TYPE_TARGET_TYPE (VALUE_TYPE (arg2));
	  if (   TYPE_CODE (t1) == TYPE_CODE_STRUCT
	      && TYPE_CODE (t2) == TYPE_CODE_STRUCT
	      && TYPE_NAME (t1) != 0) /* if name unknown, can't have supercl */
	    {
	      value v = search_struct_field (type_name_no_tag (t1),
					     value_ind (arg2), 0, t2, 1);
	      if (v)
		{
		  v = value_addr (v);
		  VALUE_TYPE (v) = type;
		  return v;
		}
	    }
	  /* No superclass found, just fall through to change ptr type.  */
	}
      VALUE_TYPE (arg2) = type;
      return arg2;
    }
  else if (VALUE_LVAL (arg2) == lval_memory)
    {
      return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2));
    }
  else if (code1 == TYPE_CODE_VOID)
    {
      return value_zero (builtin_type_void, not_lval);
    }
  else
    {
      error ("Invalid cast.");
      return 0;
    }
}

/* Create a value of type TYPE that is zero, and return it.  */

value
value_zero (type, lv)
     struct type *type;
     enum lval_type lv;
{
  register value val = allocate_value (type);

  memset (VALUE_CONTENTS (val), 0, TYPE_LENGTH (type));
  VALUE_LVAL (val) = lv;

  return val;
}

/* Return a value with type TYPE located at ADDR.  

   Call value_at only if the data needs to be fetched immediately;
   if we can be 'lazy' and defer the fetch, perhaps indefinately, call
   value_at_lazy instead.  value_at_lazy simply records the address of
   the data and sets the lazy-evaluation-required flag.  The lazy flag 
   is tested in the VALUE_CONTENTS macro, which is used if and when 
   the contents are actually required.  */

value
value_at (type, addr)
     struct type *type;
     CORE_ADDR addr;
{
  register value val = allocate_value (type);

  read_memory (addr, VALUE_CONTENTS_RAW (val), TYPE_LENGTH (type));

  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = addr;

  return val;
}

/* Return a lazy value with type TYPE located at ADDR (cf. value_at).  */

value
value_at_lazy (type, addr)
     struct type *type;
     CORE_ADDR addr;
{
  register value val = allocate_value (type);

  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = addr;
  VALUE_LAZY (val) = 1;

  return val;
}

/* Called only from the VALUE_CONTENTS macro, if the current data for
   a variable needs to be loaded into VALUE_CONTENTS(VAL).  Fetches the
   data from the user's process, and clears the lazy flag to indicate
   that the data in the buffer is valid.

   If the value is zero-length, we avoid calling read_memory, which would
   abort.  We mark the value as fetched anyway -- all 0 bytes of it.

   This function returns a value because it is used in the VALUE_CONTENTS
   macro as part of an expression, where a void would not work.  The
   value is ignored.  */

int
value_fetch_lazy (val)
     register value val;
{
  CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val);

  if (TYPE_LENGTH (VALUE_TYPE (val)))
    read_memory (addr, VALUE_CONTENTS_RAW (val), 
	         TYPE_LENGTH (VALUE_TYPE (val)));
  VALUE_LAZY (val) = 0;
  return 0;
}


/* Store the contents of FROMVAL into the location of TOVAL.
   Return a new value with the location of TOVAL and contents of FROMVAL.  */

value
value_assign (toval, fromval)
     register value toval, fromval;
{
  register struct type *type = VALUE_TYPE (toval);
  register value val;
  char raw_buffer[MAX_REGISTER_RAW_SIZE];
  char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
  int use_buffer = 0;

  COERCE_ARRAY (fromval);
  COERCE_REF (toval);

  if (VALUE_LVAL (toval) != lval_internalvar)
    fromval = value_cast (type, fromval);

  /* If TOVAL is a special machine register requiring conversion
     of program values to a special raw format,
     convert FROMVAL's contents now, with result in `raw_buffer',
     and set USE_BUFFER to the number of bytes to write.  */

  if (VALUE_REGNO (toval) >= 0
      && REGISTER_CONVERTIBLE (VALUE_REGNO (toval)))
    {
      int regno = VALUE_REGNO (toval);
      if (VALUE_TYPE (fromval) != REGISTER_VIRTUAL_TYPE (regno))
	fromval = value_cast (REGISTER_VIRTUAL_TYPE (regno), fromval);
      memcpy (virtual_buffer, VALUE_CONTENTS (fromval),
	     REGISTER_VIRTUAL_SIZE (regno));
      target_convert_from_virtual (regno, virtual_buffer, raw_buffer);
      use_buffer = REGISTER_RAW_SIZE (regno);
    }

  switch (VALUE_LVAL (toval))
    {
    case lval_internalvar:
      set_internalvar (VALUE_INTERNALVAR (toval), fromval);
      break;

    case lval_internalvar_component:
      set_internalvar_component (VALUE_INTERNALVAR (toval),
				 VALUE_OFFSET (toval),
				 VALUE_BITPOS (toval),
				 VALUE_BITSIZE (toval),
				 fromval);
      break;

    case lval_memory:
      if (VALUE_BITSIZE (toval))
	{
	  int v;		/* FIXME, this won't work for large bitfields */
	  read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
		       &v, sizeof v);
	  modify_field ((char *) &v, (int) value_as_long (fromval),
			VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
	  write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
			(char *)&v, sizeof v);
	}
      else if (use_buffer)
	write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
		      raw_buffer, use_buffer);
      else
	write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
		      VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
      break;

    case lval_register:
      if (VALUE_BITSIZE (toval))
	{
	  int v;

	  read_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
			       (char *) &v, sizeof v);
	  modify_field ((char *) &v, (int) value_as_long (fromval),
			VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
	  write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
				(char *) &v, sizeof v);
	}
      else if (use_buffer)
	write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
			      raw_buffer, use_buffer);
      else
	write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
			      VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
      break;

    case lval_reg_frame_relative:
      {
	/* value is stored in a series of registers in the frame
	   specified by the structure.  Copy that value out, modify
	   it, and copy it back in.  */
	int amount_to_copy = (VALUE_BITSIZE (toval) ? 1 : TYPE_LENGTH (type));
	int reg_size = REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval));
	int byte_offset = VALUE_OFFSET (toval) % reg_size;
	int reg_offset = VALUE_OFFSET (toval) / reg_size;
	int amount_copied;
	char *buffer = (char *) alloca (amount_to_copy);
	int regno;
	FRAME frame;

	/* Figure out which frame this is in currently.  */
	for (frame = get_current_frame ();
	     frame && FRAME_FP (frame) != VALUE_FRAME (toval);
	     frame = get_prev_frame (frame))
	  ;

	if (!frame)
	  error ("Value being assigned to is no longer active.");

	amount_to_copy += (reg_size - amount_to_copy % reg_size);

	/* Copy it out.  */
	for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
	      amount_copied = 0);
	     amount_copied < amount_to_copy;
	     amount_copied += reg_size, regno++)
	  {
	    get_saved_register (buffer + amount_copied,
				(int *)NULL, (CORE_ADDR)NULL,
				frame, regno, (enum lval_type *)NULL);
	  }

	/* Modify what needs to be modified.  */
	if (VALUE_BITSIZE (toval))
	  modify_field (buffer + byte_offset,
			(int) value_as_long (fromval),
			VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
	else if (use_buffer)
	  bcopy (raw_buffer, buffer + byte_offset, use_buffer);
	else
	  bcopy (VALUE_CONTENTS (fromval), buffer + byte_offset,
		 TYPE_LENGTH (type));

	/* Copy it back.  */
	for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
	      amount_copied = 0);
	     amount_copied < amount_to_copy;
	     amount_copied += reg_size, regno++)
	  {
	    enum lval_type lval;
	    CORE_ADDR addr;
	    int optim;

	    /* Just find out where to put it.  */
	    get_saved_register ((char *)NULL,
			        &optim, &addr, frame, regno, &lval);
	    
	    if (optim)
	      error ("Attempt to assign to a value that was optimized out.");
	    if (lval == lval_memory)
	      write_memory (addr, buffer + amount_copied, reg_size);
	    else if (lval == lval_register)
	      write_register_bytes (addr, buffer + amount_copied, reg_size);
	    else
	      error ("Attempt to assign to an unmodifiable value.");
	  }
      }
      break;
	

    default:
      error ("Left side of = operation is not an lvalue.");
    }

  /* Return a value just like TOVAL except with the contents of FROMVAL
     (except in the case of the type if TOVAL is an internalvar).  */

  if (VALUE_LVAL (toval) == lval_internalvar
      || VALUE_LVAL (toval) == lval_internalvar_component)
    {
      type = VALUE_TYPE (fromval);
    }

  val = allocate_value (type);
  bcopy (toval, val, VALUE_CONTENTS_RAW (val) - (char *) val);
  bcopy (VALUE_CONTENTS (fromval), VALUE_CONTENTS_RAW (val), TYPE_LENGTH (type));
  VALUE_TYPE (val) = type;
  
  return val;
}

/* Extend a value VAL to COUNT repetitions of its type.  */

value
value_repeat (arg1, count)
     value arg1;
     int count;
{
  register value val;

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Only values in memory can be extended with '@'.");
  if (count < 1)
    error ("Invalid number %d of repetitions.", count);

  val = allocate_repeat_value (VALUE_TYPE (arg1), count);

  read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
	       VALUE_CONTENTS_RAW (val),
	       TYPE_LENGTH (VALUE_TYPE (val)) * count);
  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);

  return val;
}

value
value_of_variable (var)
     struct symbol *var;
{
  value val;

  val = read_var_value (var, (FRAME) 0);
  if (val == 0)
    error ("Address of symbol \"%s\" is unknown.", SYMBOL_NAME (var));
  return val;
}

/* Given a value which is an array, return a value which is
   a pointer to its first (actually, zeroth) element. 
   FIXME, this should be subtracting the array's lower bound. */

value
value_coerce_array (arg1)
     value arg1;
{
  register struct type *type;

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  /* Get type of elements.  */
  if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_ARRAY)
    type = TYPE_TARGET_TYPE (VALUE_TYPE (arg1));
  else
    /* A phony array made by value_repeat.
       Its type is the type of the elements, not an array type.  */
    type = VALUE_TYPE (arg1);

  return value_from_longest (lookup_pointer_type (type),
		       (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
}

/* Given a value which is a function, return a value which is a pointer
   to it.  */

value
value_coerce_function (arg1)
     value arg1;
{

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  return value_from_longest (lookup_pointer_type (VALUE_TYPE (arg1)),
		(LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
}  

/* Return a pointer value for the object for which ARG1 is the contents.  */

value
value_addr (arg1)
     value arg1;
{
  extern value value_copy ();
  struct type *type = VALUE_TYPE (arg1);
  if (TYPE_CODE (type) == TYPE_CODE_REF)
    {
      /* Copy the value, but change the type from (T&) to (T*).
	 We keep the same location information, which is efficient,
	 and allows &(&X) to get the location containing the reference. */
      value arg2 = value_copy (arg1);
      VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
      return arg2;
    }
  if (VALUE_REPEATED (arg1)
      || TYPE_CODE (type) == TYPE_CODE_ARRAY)
    return value_coerce_array (arg1);
  if (TYPE_CODE (type) == TYPE_CODE_FUNC)
    return value_coerce_function (arg1);

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  return value_from_longest (lookup_pointer_type (type),
		(LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
}

/* Given a value of a pointer type, apply the C unary * operator to it.  */

value
value_ind (arg1)
     value arg1;
{
  COERCE_ARRAY (arg1);

  if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_MEMBER)
    error ("not implemented: member types in value_ind");

  /* Allow * on an integer so we can cast it to whatever we want.
     This returns an int, which seems like the most C-like thing
     to do.  "long long" variables are rare enough that
     BUILTIN_TYPE_LONGEST would seem to be a mistake.  */
  if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_INT)
    return value_at (builtin_type_int,
		     (CORE_ADDR) value_as_long (arg1));
  else if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR)
    return value_at_lazy (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)),
			  value_as_pointer (arg1));
  error ("Attempt to take contents of a non-pointer value.");
  return 0;  /* For lint -- never reached */
}

/* Pushing small parts of stack frames.  */

/* Push one word (the size of object that a register holds).  */

CORE_ADDR
push_word (sp, buffer)
     CORE_ADDR sp;
     REGISTER_TYPE buffer;
{
  register int len = sizeof (REGISTER_TYPE);

  SWAP_TARGET_AND_HOST (&buffer, len);
#if 1 INNER_THAN 2
  sp -= len;
  write_memory (sp, (char *)&buffer, len);
#else /* stack grows upward */
  write_memory (sp, (char *)&buffer, len);
  sp += len;
#endif /* stack grows upward */

  return sp;
}

/* Push LEN bytes with data at BUFFER.  */

CORE_ADDR
push_bytes (sp, buffer, len)
     CORE_ADDR sp;
     char *buffer;
     int len;
{
#if 1 INNER_THAN 2
  sp -= len;
  write_memory (sp, buffer, len);
#else /* stack grows upward */
  write_memory (sp, buffer, len);
  sp += len;
#endif /* stack grows upward */

  return sp;
}

/* Push onto the stack the specified value VALUE.  */

CORE_ADDR
value_push (sp, arg)
     register CORE_ADDR sp;
     value arg;
{
  register int len = TYPE_LENGTH (VALUE_TYPE (arg));

#if 1 INNER_THAN 2
  sp -= len;
  write_memory (sp, VALUE_CONTENTS (arg), len);
#else /* stack grows upward */
  write_memory (sp, VALUE_CONTENTS (arg), len);
  sp += len;
#endif /* stack grows upward */

  return sp;
}

/* Perform the standard coercions that are specified
   for arguments to be passed to C functions.  */

value
value_arg_coerce (arg)
     value arg;
{
  register struct type *type;

  COERCE_ENUM (arg);

  type = VALUE_TYPE (arg);

  if (TYPE_CODE (type) == TYPE_CODE_INT
      && TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
    return value_cast (builtin_type_int, arg);

  if (TYPE_CODE (type) == TYPE_CODE_FLT
      && TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
    return value_cast (builtin_type_double, arg);

  return arg;
}

/* Push the value ARG, first coercing it as an argument
   to a C function.  */

CORE_ADDR
value_arg_push (sp, arg)
     register CORE_ADDR sp;
     value arg;
{
  return value_push (sp, value_arg_coerce (arg));
}

/* Determine a function's address and its return type from its value. 
   Calls error() if the function is not valid for calling.  */

CORE_ADDR
find_function_addr (function, retval_type)
     value function;
     struct type **retval_type;
{
  register struct type *ftype = VALUE_TYPE (function);
  register enum type_code code = TYPE_CODE (ftype);
  struct type *value_type;
  CORE_ADDR funaddr;

  /* If it's a member function, just look at the function
     part of it.  */

  /* Determine address to call.  */
  if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
    {
      funaddr = VALUE_ADDRESS (function);
      value_type = TYPE_TARGET_TYPE (ftype);
    }
  else if (code == TYPE_CODE_PTR)
    {
      funaddr = value_as_pointer (function);
      if (TYPE_CODE (TYPE_TARGET_TYPE (ftype)) == TYPE_CODE_FUNC
	  || TYPE_CODE (TYPE_TARGET_TYPE (ftype)) == TYPE_CODE_METHOD)
	value_type = TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (ftype));
      else
	value_type = builtin_type_int;
    }
  else if (code == TYPE_CODE_INT)
    {
      /* Handle the case of functions lacking debugging info.
	 Their values are characters since their addresses are char */
      if (TYPE_LENGTH (ftype) == 1)
	funaddr = value_as_pointer (value_addr (function));
      else
	/* Handle integer used as address of a function.  */
	funaddr = (CORE_ADDR) value_as_long (function);

      value_type = builtin_type_int;
    }
  else
    error ("Invalid data type for function to be called.");

  *retval_type = value_type;
  return funaddr;
}

#if defined (CALL_DUMMY)
/* All this stuff with a dummy frame may seem unnecessarily complicated
   (why not just save registers in GDB?).  The purpose of pushing a dummy
   frame which looks just like a real frame is so that if you call a
   function and then hit a breakpoint (get a signal, etc), "backtrace"
   will look right.  Whether the backtrace needs to actually show the
   stack at the time the inferior function was called is debatable, but
   it certainly needs to not display garbage.  So if you are contemplating
   making dummy frames be different from normal frames, consider that.  */

/* Perform a function call in the inferior.
   ARGS is a vector of values of arguments (NARGS of them).
   FUNCTION is a value, the function to be called.
   Returns a value representing what the function returned.
   May fail to return, if a breakpoint or signal is hit
   during the execution of the function.  */

value
call_function_by_hand (function, nargs, args)
     value function;
     int nargs;
     value *args;
{
  register CORE_ADDR sp;
  register int i;
  CORE_ADDR start_sp;
  /* CALL_DUMMY is an array of words (REGISTER_TYPE), but each word
     is in host byte order.  It is switched to target byte order before calling
     FIX_CALL_DUMMY.  */
  static REGISTER_TYPE dummy[] = CALL_DUMMY;
  REGISTER_TYPE dummy1[sizeof dummy / sizeof (REGISTER_TYPE)];
  CORE_ADDR old_sp;
  struct type *value_type;
  unsigned char struct_return;
  CORE_ADDR struct_addr;
  struct inferior_status inf_status;
  struct cleanup *old_chain;
  CORE_ADDR funaddr;
  int using_gcc;

  if (!target_has_execution)
    noprocess();

  save_inferior_status (&inf_status, 1);
  old_chain = make_cleanup (restore_inferior_status, &inf_status);

  /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
     (and POP_FRAME for restoring them).  (At least on most machines)
     they are saved on the stack in the inferior.  */
  PUSH_DUMMY_FRAME;

  old_sp = sp = read_register (SP_REGNUM);

#if 1 INNER_THAN 2		/* Stack grows down */
  sp -= sizeof dummy;
  start_sp = sp;
#else				/* Stack grows up */
  start_sp = sp;
  sp += sizeof dummy;
#endif

  funaddr = find_function_addr (function, &value_type);

  {
    struct block *b = block_for_pc (funaddr);
    /* If compiled without -g, assume GCC.  */
    using_gcc = b == NULL || BLOCK_GCC_COMPILED (b);
  }

  /* Are we returning a value using a structure return or a normal
     value return? */

  struct_return = using_struct_return (function, funaddr, value_type,
				       using_gcc);

  /* Create a call sequence customized for this function
     and the number of arguments for it.  */
  bcopy (dummy, dummy1, sizeof dummy);
  for (i = 0; i < sizeof dummy / sizeof (REGISTER_TYPE); i++)
    SWAP_TARGET_AND_HOST (&dummy1[i], sizeof (REGISTER_TYPE));
  FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
		  value_type, using_gcc);

#if CALL_DUMMY_LOCATION == ON_STACK
  write_memory (start_sp, (char *)dummy1, sizeof dummy);

#else /* Not on stack.  */
#if CALL_DUMMY_LOCATION == BEFORE_TEXT_END
  /* Convex Unix prohibits executing in the stack segment. */
  /* Hope there is empty room at the top of the text segment. */
  {
    extern CORE_ADDR text_end;
    static checked = 0;
    if (!checked)
      for (start_sp = text_end - sizeof dummy; start_sp < text_end; ++start_sp)
	if (read_memory_integer (start_sp, 1) != 0)
	  error ("text segment full -- no place to put call");
    checked = 1;
    sp = old_sp;
    start_sp = text_end - sizeof dummy;
    write_memory (start_sp, (char *)dummy1, sizeof dummy);
  }
#else /* After text_end.  */
  {
    extern CORE_ADDR text_end;
    int errcode;
    sp = old_sp;
    start_sp = text_end;
    errcode = target_write_memory (start_sp, (char *)dummy1, sizeof dummy);
    if (errcode != 0)
      error ("Cannot write text segment -- call_function failed");
  }
#endif /* After text_end.  */
#endif /* Not on stack.  */

#ifdef lint
  sp = old_sp;		/* It really is used, for some ifdef's... */
#endif

#ifdef STACK_ALIGN
  /* If stack grows down, we must leave a hole at the top. */
  {
    int len = 0;

    /* Reserve space for the return structure to be written on the
       stack, if necessary */

    if (struct_return)
      len += TYPE_LENGTH (value_type);
    
    for (i = nargs - 1; i >= 0; i--)
      len += TYPE_LENGTH (VALUE_TYPE (value_arg_coerce (args[i])));
#ifdef CALL_DUMMY_STACK_ADJUST
    len += CALL_DUMMY_STACK_ADJUST;
#endif
#if 1 INNER_THAN 2
    sp -= STACK_ALIGN (len) - len;
#else
    sp += STACK_ALIGN (len) - len;
#endif
  }
#endif /* STACK_ALIGN */

    /* Reserve space for the return structure to be written on the
       stack, if necessary */

    if (struct_return)
      {
#if 1 INNER_THAN 2
	sp -= TYPE_LENGTH (value_type);
	struct_addr = sp;
#else
	struct_addr = sp;
	sp += TYPE_LENGTH (value_type);
#endif
      }

#if defined (REG_STRUCT_HAS_ADDR)
  {
    /* This is a machine like the sparc, where we need to pass a pointer
       to the structure, not the structure itself.  */
    if (REG_STRUCT_HAS_ADDR (using_gcc))
      for (i = nargs - 1; i >= 0; i--)
	if (TYPE_CODE (VALUE_TYPE (args[i])) == TYPE_CODE_STRUCT)
	  {
	    CORE_ADDR addr;
#if !(1 INNER_THAN 2)
	    /* The stack grows up, so the address of the thing we push
	       is the stack pointer before we push it.  */
	    addr = sp;
#endif
	    /* Push the structure.  */
	    sp = value_push (sp, args[i]);
#if 1 INNER_THAN 2
	    /* The stack grows down, so the address of the thing we push
	       is the stack pointer after we push it.  */
	    addr = sp;
#endif
	    /* The value we're going to pass is the address of the thing
	       we just pushed.  */
	    args[i] = value_from_longest (lookup_pointer_type (value_type),
				       (LONGEST) addr);
	  }
  }
#endif /* REG_STRUCT_HAS_ADDR.  */

#ifdef PUSH_ARGUMENTS
  PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr);
#else /* !PUSH_ARGUMENTS */
  for (i = nargs - 1; i >= 0; i--)
    sp = value_arg_push (sp, args[i]);
#endif /* !PUSH_ARGUMENTS */

#ifdef CALL_DUMMY_STACK_ADJUST
#if 1 INNER_THAN 2
  sp -= CALL_DUMMY_STACK_ADJUST;
#else
  sp += CALL_DUMMY_STACK_ADJUST;
#endif
#endif /* CALL_DUMMY_STACK_ADJUST */

  /* Store the address at which the structure is supposed to be
     written.  Note that this (and the code which reserved the space
     above) assumes that gcc was used to compile this function.  Since
     it doesn't cost us anything but space and if the function is pcc
     it will ignore this value, we will make that assumption.

     Also note that on some machines (like the sparc) pcc uses a 
     convention like gcc's.  */

  if (struct_return)
    STORE_STRUCT_RETURN (struct_addr, sp);

  /* Write the stack pointer.  This is here because the statements above
     might fool with it.  On SPARC, this write also stores the register
     window into the right place in the new stack frame, which otherwise
     wouldn't happen.  (See write_inferior_registers in sparc-xdep.c.)  */
  write_register (SP_REGNUM, sp);

  /* Figure out the value returned by the function.  */
  {
    char retbuf[REGISTER_BYTES];

    /* Execute the stack dummy routine, calling FUNCTION.
       When it is done, discard the empty frame
       after storing the contents of all regs into retbuf.  */
    run_stack_dummy (start_sp + CALL_DUMMY_START_OFFSET, retbuf);

    do_cleanups (old_chain);

    return value_being_returned (value_type, retbuf, struct_return);
  }
}
#else /* no CALL_DUMMY.  */
value
call_function_by_hand (function, nargs, args)
     value function;
     int nargs;
     value *args;
{
  error ("Cannot invoke functions on this machine.");
}
#endif /* no CALL_DUMMY.  */

/* Create a value for a string constant:
   Call the function malloc in the inferior to get space for it,
   then copy the data into that space
   and then return the address with type char *.
   PTR points to the string constant data; LEN is number of characters.  */

value
value_string (ptr, len)
     char *ptr;
     int len;
{
  register value val;
  register struct symbol *sym;
  value blocklen;
  register char *copy = (char *) alloca (len + 1);
  char *i = ptr;
  register char *o = copy, *ibeg = ptr;
  register int c;

  /* Copy the string into COPY, processing escapes.
     We could not conveniently process them in the parser
     because the string there wants to be a substring of the input.  */

  while (i - ibeg < len)
    {
      c = *i++;
      if (c == '\\')
	{
	  c = parse_escape (&i);
	  if (c == -1)
	    continue;
	}
      *o++ = c;
    }
  *o = 0;

  /* Get the length of the string after escapes are processed.  */

  len = o - copy;

  /* Find the address of malloc in the inferior.  */

  sym = lookup_symbol ("malloc", 0, VAR_NAMESPACE, 0, NULL);
  if (sym != 0)
    {
      if (SYMBOL_CLASS (sym) != LOC_BLOCK)
	error ("\"malloc\" exists in this program but is not a function.");
      val = value_of_variable (sym);
    }
  else
    {
      register int j;
      j = lookup_misc_func ("malloc");
      if (j >= 0)
	val = value_from_longest (
		lookup_pointer_type (lookup_function_type (
		  		      lookup_pointer_type (builtin_type_char))),
			       (LONGEST) misc_function_vector[j].address);
      else
	error ("String constants require the program to have a function \"malloc\".");
    }

  blocklen = value_from_longest (builtin_type_int, (LONGEST) (len + 1));
  val = call_function_by_hand (val, 1, &blocklen);
  if (value_zerop (val))
    error ("No memory available for string constant.");
  write_memory (value_as_pointer (val), copy, len + 1);
  VALUE_TYPE (val) = lookup_pointer_type (builtin_type_char);
  return val;
}

/* Helper function used by value_struct_elt to recurse through baseclasses.
   Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
   and search in it assuming it has (class) type TYPE.
   If found, return value, else return NULL.

   If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
   look for a baseclass named NAME.  */

static value
search_struct_field (name, arg1, offset, type, looking_for_baseclass)
     char *name;
     register value arg1;
     int offset;
     register struct type *type;
     int looking_for_baseclass;
{
  int i;

  check_stub_type (type);

  if (! looking_for_baseclass)
    for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
      {
	char *t_field_name = TYPE_FIELD_NAME (type, i);

	if (t_field_name && !strcmp (t_field_name, name))
	  {
	    value v = (TYPE_FIELD_STATIC (type, i)
		       ? value_static_field (type, name, i)
		       : value_primitive_field (arg1, offset, i, type));
	    if (v == 0)
	      error("there is no field named %s", name);
	    return v;
	  }
      }

  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    {
      value v;
      /* If we are looking for baseclasses, this is what we get when we
	 hit them.  */
      int found_baseclass = (looking_for_baseclass
			     && !strcmp (name, TYPE_BASECLASS_NAME (type, i)));

      if (BASETYPE_VIA_VIRTUAL (type, i))
	{
	  value v2;
	  baseclass_addr (type, i, VALUE_CONTENTS (arg1) + offset,
			  &v2, (int *)NULL);
	  if (v2 == 0)
	    error ("virtual baseclass botch");
	  if (found_baseclass)
	    return v2;
	  v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
				   looking_for_baseclass);
	  if (v) return v;
	  else continue;
	}
      if (found_baseclass)
	v = value_primitive_field (arg1, offset, i, type);
      else
	v = search_struct_field (name, arg1,
				 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
				 TYPE_BASECLASS (type, i),
				 looking_for_baseclass);
      if (v) return v;
    }
  return NULL;
}

/* Helper function used by value_struct_elt to recurse through baseclasses.
   Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
   and search in it assuming it has (class) type TYPE.
   If found, return value, else return NULL. */

static value
search_struct_method (name, arg1, args, offset, static_memfuncp, type)
     char *name;
     register value arg1, *args;
     int offset, *static_memfuncp;
     register struct type *type;
{
  int i;

  check_stub_type (type);
  for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
    {
      char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
      if (t_field_name && !strcmp (t_field_name, name))
	{
	  int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
	  struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);

	  if (j > 0 && args == 0)
	    error ("cannot resolve overloaded method `%s'", name);
	  while (j >= 0)
	    {
	      if (TYPE_FN_FIELD_STUB (f, j))
		check_stub_method (type, i, j);
	      if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
			    TYPE_FN_FIELD_ARGS (f, j), args))
		{
		  if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
		    return (value)value_virtual_fn_field (arg1, f, j, type);
		  if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
		    *static_memfuncp = 1;
		  return (value)value_fn_field (f, j);
		}
	      j--;
	    }
	}
    }

  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    {
      value v;

      if (BASETYPE_VIA_VIRTUAL (type, i))
	{
	  value v2;
	  baseclass_addr (type, i, VALUE_CONTENTS (arg1) + offset,
			  &v2, (int *)NULL);
	  if (v2 == 0)
	    error ("virtual baseclass botch");
	  v = search_struct_method (name, v2, args, 0,
				    static_memfuncp, TYPE_BASECLASS (type, i));
	  if (v) return v;
	  else continue;
	}

      v = search_struct_method (name, arg1, args,
				TYPE_BASECLASS_BITPOS (type, i) / 8,
				static_memfuncp, TYPE_BASECLASS (type, i));
      if (v) return v;
    }
  return NULL;
}

/* Given *ARGP, a value of type (pointer to a)* structure/union,
   extract the component named NAME from the ultimate target structure/union
   and return it as a value with its appropriate type.
   ERR is used in the error message if *ARGP's type is wrong.

   C++: ARGS is a list of argument types to aid in the selection of
   an appropriate method. Also, handle derived types.

   STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
   where the truthvalue of whether the function that was resolved was
   a static member function or not is stored.

   ERR is an error message to be printed in case the field is not found.  */

value
value_struct_elt (argp, args, name, static_memfuncp, err)
     register value *argp, *args;
     char *name;
     int *static_memfuncp;
     char *err;
{
  register struct type *t;
  value v;

  COERCE_ARRAY (*argp);

  t = VALUE_TYPE (*argp);

  /* Follow pointers until we get to a non-pointer.  */

  while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
    {
      *argp = value_ind (*argp);
      /* Don't coerce fn pointer to fn and then back again!  */
      if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
	COERCE_ARRAY (*argp);
      t = VALUE_TYPE (*argp);
    }

  if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
    error ("not implemented: member type in value_struct_elt");

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Attempt to extract a component of a value that is not a %s.", err);

  /* Assume it's not, unless we see that it is.  */
  if (static_memfuncp)
    *static_memfuncp =0;

  if (!args)
    {
      /* if there are no arguments ...do this...  */

      /* Try as a field first, because if we succeed, there
	 is less work to be done.  */
      v = search_struct_field (name, *argp, 0, t, 0);
      if (v)
	return v;

      /* C++: If it was not found as a data field, then try to
         return it as a pointer to a method.  */

      if (destructor_name_p (name, t))
	error ("Cannot get value of destructor");

      v = search_struct_method (name, *argp, args, 0, static_memfuncp, t);

      if (v == 0)
	{
	  if (TYPE_NFN_FIELDS (t))
	    error ("There is no member or method named %s.", name);
	  else
	    error ("There is no member named %s.", name);
	}
      return v;
    }

  if (destructor_name_p (name, t))
    {
      if (!args[1])
	{
	  /* destructors are a special case.  */
	  return (value)value_fn_field (TYPE_FN_FIELDLIST1 (t, 0),
					TYPE_FN_FIELDLIST_LENGTH (t, 0));
	}
      else
	{
	  error ("destructor should not have any argument");
	}
    }
  else
    v = search_struct_method (name, *argp, args, 0, static_memfuncp, t);

  if (v == 0)
    {
      /* See if user tried to invoke data as function.  If so,
	 hand it back.  If it's not callable (i.e., a pointer to function),
	 gdb should give an error.  */
      v = search_struct_field (name, *argp, 0, t, 0);
    }

  if (!v)
    error ("Structure has no component named %s.", name);
  return v;
}

/* C++: return 1 is NAME is a legitimate name for the destructor
   of type TYPE.  If TYPE does not have a destructor, or
   if NAME is inappropriate for TYPE, an error is signaled.  */
int
destructor_name_p (name, type)
     const char *name;
     const struct type *type;
{
  /* destructors are a special case.  */

  if (name[0] == '~')
    {
      char *dname = type_name_no_tag (type);
      if (strcmp (dname, name+1))
	error ("name of destructor must equal name of class");
      else
	return 1;
    }
  return 0;
}

/* Helper function for check_field: Given TYPE, a structure/union,
   return 1 if the component named NAME from the ultimate
   target structure/union is defined, otherwise, return 0. */

static int
check_field_in (type, name)
     register struct type *type;
     char *name;
{
  register int i;

  for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
    {
      char *t_field_name = TYPE_FIELD_NAME (type, i);
      if (t_field_name && !strcmp (t_field_name, name))
	return 1;
    }

  /* C++: If it was not found as a data field, then try to
     return it as a pointer to a method.  */

  /* Destructors are a special case.  */
  if (destructor_name_p (name, type))
    return 1;

  for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
    {
      if (!strcmp (TYPE_FN_FIELDLIST_NAME (type, i), name))
	return 1;
    }

  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    if (check_field_in (TYPE_BASECLASS (type, i), name))
      return 1;
      
  return 0;
}


/* C++: Given ARG1, a value of type (pointer to a)* structure/union,
   return 1 if the component named NAME from the ultimate
   target structure/union is defined, otherwise, return 0.  */

int
check_field (arg1, name)
     register const value arg1;
     const char *name;
{
  register struct type *t;

  COERCE_ARRAY (arg1);

  t = VALUE_TYPE (arg1);

  /* Follow pointers until we get to a non-pointer.  */

  while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
    t = TYPE_TARGET_TYPE (t);

  if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
    error ("not implemented: member type in check_field");

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Internal error: `this' is not an aggregate");

  return check_field_in (t, name);
}

/* C++: Given an aggregate type DOMAIN, and a member name NAME,
   return the address of this member as a "pointer to member"
   type.  If INTYPE is non-null, then it will be the type
   of the member we are looking for.  This will help us resolve
   "pointers to member functions".  This function is only used
   to resolve user expressions of the form "&class::member".  */

value
value_struct_elt_for_address (domain, intype, name)
     struct type *domain, *intype;
     char *name;
{
  register struct type *t = domain;
  register int i;
  value v;

  struct type *baseclass;

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Internal error: non-aggregate type to value_struct_elt_for_address");

  baseclass = t;

  while (t)
    {
      for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
	{
	  char *t_field_name = TYPE_FIELD_NAME (t, i);

	  if (t_field_name && !strcmp (t_field_name, name))
	    {
	      if (TYPE_FIELD_STATIC (t, i))
		{
		  char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (t, i);
		  struct symbol *sym =
		      lookup_symbol (phys_name, 0, VAR_NAMESPACE, 0, NULL);
		  if (! sym)
		    error (
	"Internal error: could not find physical static variable named %s",
			   phys_name);
		  return value_from_longest (
			lookup_pointer_type (TYPE_FIELD_TYPE (t, i)),
				      (LONGEST)SYMBOL_BLOCK_VALUE (sym));
	        }
	      if (TYPE_FIELD_PACKED (t, i))
		error ("pointers to bitfield members not allowed");

	      return value_from_longest (
		    lookup_pointer_type (
		      lookup_member_type (TYPE_FIELD_TYPE (t, i), baseclass)),
				   (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
	    }
	}

      if (TYPE_N_BASECLASSES (t) == 0)
	break;

      t = TYPE_BASECLASS (t, 0);
    }

  /* C++: If it was not found as a data field, then try to
     return it as a pointer to a method.  */
  t = baseclass;

  /* Destructors are a special case.  */
  if (destructor_name_p (name, t))
    {
      error ("member pointers to destructors not implemented yet");
    }

  /* Perform all necessary dereferencing.  */
  while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
    intype = TYPE_TARGET_TYPE (intype);

  while (t)
    {
      for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
	{
	  if (!strcmp (TYPE_FN_FIELDLIST_NAME (t, i), name))
	    {
	      int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
	      struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);

	      if (intype == 0 && j > 1)
		error ("non-unique member `%s' requires type instantiation", name);
	      if (intype)
		{
		  while (j--)
		    if (TYPE_FN_FIELD_TYPE (f, j) == intype)
		      break;
		  if (j < 0)
		    error ("no member function matches that type instantiation");
		}
	      else
		j = 0;

	      if (TYPE_FN_FIELD_STUB (f, j))
	        check_stub_method (t, i, j);
	      if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
		{
		  return value_from_longest (
	                lookup_pointer_type (
			  lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
					      baseclass)),
				       (LONGEST) TYPE_FN_FIELD_VOFFSET (f, j));
		}
	      else
		{
		  struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
						    0, VAR_NAMESPACE, 0, NULL);
		  v = locate_var_value (s, 0);
	          VALUE_TYPE (v) = lookup_pointer_type (
			lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
					    baseclass));
	          return v;
		}
	    }
	}

      if (TYPE_N_BASECLASSES (t) == 0)
	break;

      t = TYPE_BASECLASS (t, 0);
    }
  return 0;
}

/* Compare two argument lists and return the position in which they differ,
   or zero if equal.

   STATICP is nonzero if the T1 argument list came from a
   static member function.

   For non-static member functions, we ignore the first argument,
   which is the type of the instance variable.  This is because we want
   to handle calls with objects from derived classes.  This is not
   entirely correct: we should actually check to make sure that a
   requested operation is type secure, shouldn't we?  FIXME.  */

int
typecmp (staticp, t1, t2)
     int staticp;
     struct type *t1[];
     value t2[];
{
  int i;

  if (t2 == 0)
    return 1;
  if (staticp && t1 == 0)
    return t2[1] != 0;
  if (t1 == 0)
    return 1;
  if (t1[0]->code == TYPE_CODE_VOID) return 0;
  if (t1[!staticp] == 0) return 0;
  for (i = !staticp; t1[i] && t1[i]->code != TYPE_CODE_VOID; i++)
    {
      if (! t2[i]
	  || t1[i]->code != t2[i]->type->code
/* Too pessimistic:  || t1[i]->target_type != t2[i]->type->target_type */
 )
	return i+1;
    }
  if (!t1[i]) return 0;
  return t2[i] ? i+1 : 0;
}

/* C++: return the value of the class instance variable, if one exists.
   Flag COMPLAIN signals an error if the request is made in an
   inappropriate context.  */
value
value_of_this (complain)
     int complain;
{
  extern FRAME selected_frame;
  struct symbol *func, *sym;
  struct block *b;
  int i;
  static const char funny_this[] = "this";
  value this;

  if (selected_frame == 0)
    if (complain)
      error ("no frame selected");
    else return 0;

  func = get_frame_function (selected_frame);
  if (!func)
    {
      if (complain)
	error ("no `this' in nameless context");
      else return 0;
    }

  b = SYMBOL_BLOCK_VALUE (func);
  i = BLOCK_NSYMS (b);
  if (i <= 0)
    if (complain)
      error ("no args, no `this'");
    else return 0;

  /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
     symbol instead of the LOC_ARG one (if both exist).  */
  sym = lookup_block_symbol (b, funny_this, VAR_NAMESPACE);
  if (sym == NULL)
    {
      if (complain)
	error ("current stack frame not in method");
      else
	return NULL;
    }

  this = read_var_value (sym, selected_frame);
  if (this == 0 && complain)
    error ("`this' argument at unknown address");
  return this;
}