aboutsummaryrefslogtreecommitdiff
path: root/ld/ldexp.c
blob: 86ae7110bfb9ac5132be041b57d4e8f0d712cbb5 (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
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
/* This module handles expression trees.
   Copyright (C) 1991-2018 Free Software Foundation, Inc.
   Written by Steve Chamberlain of Cygnus Support <sac@cygnus.com>.

   This file is part of the GNU Binutils.

   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 3 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., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */


/* This module is in charge of working out the contents of expressions.

   It has to keep track of the relative/absness of a symbol etc. This
   is done by keeping all values in a struct (an etree_value_type)
   which contains a value, a section to which it is relative and a
   valid bit.  */

#include "sysdep.h"
#include "bfd.h"
#include "bfdlink.h"

#include "ld.h"
#include "ldmain.h"
#include "ldmisc.h"
#include "ldexp.h"
#include "ldlex.h"
#include <ldgram.h>
#include "ldlang.h"
#include "libiberty.h"
#include "safe-ctype.h"

static void exp_fold_tree_1 (etree_type *);
static bfd_vma align_n (bfd_vma, bfd_vma);

segment_type *segments;

struct ldexp_control expld;

/* This structure records symbols for which we need to keep track of
   definedness for use in the DEFINED () test.  It is also used in
   making absolute symbols section relative late in the link.   */

struct definedness_hash_entry
{
  struct bfd_hash_entry root;

  /* If this symbol was assigned from "dot" outside of an output
     section statement, the section we'd like it relative to.  */
  asection *final_sec;

  /* Low bits of iteration count.  Symbols with matching iteration have
     been defined in this pass over the script.  */
  unsigned int iteration : 8;

  /* Symbol was defined by an object file.  */
  unsigned int by_object : 1;
};

static struct bfd_hash_table definedness_table;

/* Print the string representation of the given token.  Surround it
   with spaces if INFIX_P is TRUE.  */

static void
exp_print_token (token_code_type code, int infix_p)
{
  static const struct
  {
    token_code_type code;
    const char *name;
  }
  table[] =
  {
    { INT, "int" },
    { NAME, "NAME" },
    { PLUSEQ, "+=" },
    { MINUSEQ, "-=" },
    { MULTEQ, "*=" },
    { DIVEQ, "/=" },
    { LSHIFTEQ, "<<=" },
    { RSHIFTEQ, ">>=" },
    { ANDEQ, "&=" },
    { OREQ, "|=" },
    { OROR, "||" },
    { ANDAND, "&&" },
    { EQ, "==" },
    { NE, "!=" },
    { LE, "<=" },
    { GE, ">=" },
    { LSHIFT, "<<" },
    { RSHIFT, ">>" },
    { LOG2CEIL, "LOG2CEIL" },
    { ALIGN_K, "ALIGN" },
    { BLOCK, "BLOCK" },
    { QUAD, "QUAD" },
    { SQUAD, "SQUAD" },
    { LONG, "LONG" },
    { SHORT, "SHORT" },
    { BYTE, "BYTE" },
    { SECTIONS, "SECTIONS" },
    { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
    { MEMORY, "MEMORY" },
    { DEFINED, "DEFINED" },
    { TARGET_K, "TARGET" },
    { SEARCH_DIR, "SEARCH_DIR" },
    { MAP, "MAP" },
    { ENTRY, "ENTRY" },
    { NEXT, "NEXT" },
    { ALIGNOF, "ALIGNOF" },
    { SIZEOF, "SIZEOF" },
    { ADDR, "ADDR" },
    { LOADADDR, "LOADADDR" },
    { CONSTANT, "CONSTANT" },
    { ABSOLUTE, "ABSOLUTE" },
    { MAX_K, "MAX" },
    { MIN_K, "MIN" },
    { ASSERT_K, "ASSERT" },
    { REL, "relocatable" },
    { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
    { DATA_SEGMENT_RELRO_END, "DATA_SEGMENT_RELRO_END" },
    { DATA_SEGMENT_END, "DATA_SEGMENT_END" },
    { TEXT_SEGMENT_ALIGN, "TEXT_SEGMENT_ALIGN" },
    { TEXT_SEGMENT_RELRO_END, "TEXT_SEGMENT_RELRO_END" },
    { TEXT_SEGMENT_END, "TEXT_SEGMENT_END" },
    { ORIGIN, "ORIGIN" },
    { LENGTH, "LENGTH" },
    { SEGMENT_START, "SEGMENT_START" }
  };
  unsigned int idx;

  for (idx = 0; idx < ARRAY_SIZE (table); idx++)
    if (table[idx].code == code)
      break;

  if (infix_p)
    fputc (' ', config.map_file);

  if (idx < ARRAY_SIZE (table))
    fputs (table[idx].name, config.map_file);
  else if (code < 127)
    fputc (code, config.map_file);
  else
    fprintf (config.map_file, "<code %d>", code);

  if (infix_p)
    fputc (' ', config.map_file);
}

static void
make_log2ceil (void)
{
  bfd_vma value = expld.result.value;
  bfd_vma result = -1;
  bfd_boolean round_up = FALSE;

  do
    {
      result++;
      /* If more than one bit is set in the value we will need to round up.  */
      if ((value > 1) && (value & 1))
	round_up = TRUE;
    }
  while (value >>= 1);

  if (round_up)
    result += 1;
  expld.result.section = NULL;
  expld.result.value = result;
}

static void
make_abs (void)
{
  if (expld.result.section != NULL)
    expld.result.value += expld.result.section->vma;
  expld.result.section = bfd_abs_section_ptr;
  expld.rel_from_abs = FALSE;
}

static void
new_abs (bfd_vma value)
{
  expld.result.valid_p = TRUE;
  expld.result.section = bfd_abs_section_ptr;
  expld.result.value = value;
  expld.result.str = NULL;
}

etree_type *
exp_intop (bfd_vma value)
{
  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
  new_e->type.node_code = INT;
  new_e->type.filename = ldlex_filename ();
  new_e->type.lineno = lineno;
  new_e->value.value = value;
  new_e->value.str = NULL;
  new_e->type.node_class = etree_value;
  return new_e;
}

etree_type *
exp_bigintop (bfd_vma value, char *str)
{
  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
  new_e->type.node_code = INT;
  new_e->type.filename = ldlex_filename ();
  new_e->type.lineno = lineno;
  new_e->value.value = value;
  new_e->value.str = str;
  new_e->type.node_class = etree_value;
  return new_e;
}

/* Build an expression representing an unnamed relocatable value.  */

etree_type *
exp_relop (asection *section, bfd_vma value)
{
  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->rel));
  new_e->type.node_code = REL;
  new_e->type.filename = ldlex_filename ();
  new_e->type.lineno = lineno;
  new_e->type.node_class = etree_rel;
  new_e->rel.section = section;
  new_e->rel.value = value;
  return new_e;
}

static void
new_number (bfd_vma value)
{
  expld.result.valid_p = TRUE;
  expld.result.value = value;
  expld.result.str = NULL;
  expld.result.section = NULL;
}

static void
new_rel (bfd_vma value, asection *section)
{
  expld.result.valid_p = TRUE;
  expld.result.value = value;
  expld.result.str = NULL;
  expld.result.section = section;
}

static void
new_rel_from_abs (bfd_vma value)
{
  asection *s = expld.section;

  expld.rel_from_abs = TRUE;
  expld.result.valid_p = TRUE;
  expld.result.value = value - s->vma;
  expld.result.str = NULL;
  expld.result.section = s;
}

/* New-function for the definedness hash table.  */

static struct bfd_hash_entry *
definedness_newfunc (struct bfd_hash_entry *entry,
		     struct bfd_hash_table *table ATTRIBUTE_UNUSED,
		     const char *name ATTRIBUTE_UNUSED)
{
  struct definedness_hash_entry *ret = (struct definedness_hash_entry *) entry;

  if (ret == NULL)
    ret = (struct definedness_hash_entry *)
      bfd_hash_allocate (table, sizeof (struct definedness_hash_entry));

  if (ret == NULL)
    einfo (_("%P%F: bfd_hash_allocate failed creating symbol %s\n"), name);

  ret->by_object = 0;
  ret->iteration = 0;
  return &ret->root;
}

/* Called during processing of linker script script expressions.
   For symbols assigned in a linker script, return a struct describing
   where the symbol is defined relative to the current expression,
   otherwise return NULL.  */

static struct definedness_hash_entry *
symbol_defined (const char *name)
{
  return ((struct definedness_hash_entry *)
	  bfd_hash_lookup (&definedness_table, name, FALSE, FALSE));
}

/* Update the definedness state of NAME.  Return FALSE if script symbol
   is multiply defining a strong symbol in an object.  */

static bfd_boolean
update_definedness (const char *name, struct bfd_link_hash_entry *h)
{
  bfd_boolean ret;
  struct definedness_hash_entry *defentry
    = (struct definedness_hash_entry *)
    bfd_hash_lookup (&definedness_table, name, TRUE, FALSE);

  if (defentry == NULL)
    einfo (_("%P%F: bfd_hash_lookup failed creating symbol %s\n"), name);

  /* If the symbol was already defined, and not by a script, then it
     must be defined by an object file or by the linker target code.  */
  ret = TRUE;
  if (!h->ldscript_def
      && (h->type == bfd_link_hash_defined
	  || h->type == bfd_link_hash_defweak
	  || h->type == bfd_link_hash_common))
    {
      defentry->by_object = 1;
      if (h->type == bfd_link_hash_defined
	  && h->u.def.section->output_section != NULL
	  && !h->linker_def)
	ret = FALSE;
    }

  defentry->iteration = lang_statement_iteration;
  defentry->final_sec = bfd_abs_section_ptr;
  if (expld.phase == lang_final_phase_enum
      && expld.rel_from_abs
      && expld.result.section == bfd_abs_section_ptr)
    defentry->final_sec = section_for_dot ();
  return ret;
}

static void
fold_segment_end (seg_align_type *seg)
{
  if (expld.phase == lang_first_phase_enum
      || expld.section != bfd_abs_section_ptr)
    {
      expld.result.valid_p = FALSE;
    }
  else if (seg->phase == exp_seg_align_seen
	   || seg->phase == exp_seg_relro_seen)
    {
      seg->phase = exp_seg_end_seen;
      seg->end = expld.result.value;
    }
  else if (seg->phase == exp_seg_done
	   || seg->phase == exp_seg_adjust
	   || seg->phase == exp_seg_relro_adjust)
    {
      /* OK.  */
    }
  else
    expld.result.valid_p = FALSE;
}

static void
fold_unary (etree_type *tree)
{
  exp_fold_tree_1 (tree->unary.child);
  if (expld.result.valid_p)
    {
      switch (tree->type.node_code)
	{
	case ALIGN_K:
	  if (expld.phase != lang_first_phase_enum)
	    new_rel_from_abs (align_n (expld.dot, expld.result.value));
	  else
	    expld.result.valid_p = FALSE;
	  break;

	case ABSOLUTE:
	  make_abs ();
	  break;

	case LOG2CEIL:
	  make_log2ceil ();
	  break;

	case '~':
	  expld.result.value = ~expld.result.value;
	  break;

	case '!':
	  expld.result.value = !expld.result.value;
	  break;

	case '-':
	  expld.result.value = -expld.result.value;
	  break;

	case NEXT:
	  /* Return next place aligned to value.  */
	  if (expld.phase != lang_first_phase_enum)
	    {
	      make_abs ();
	      expld.result.value = align_n (expld.dot, expld.result.value);
	    }
	  else
	    expld.result.valid_p = FALSE;
	  break;

	case DATA_SEGMENT_END:
	  fold_segment_end (&expld.dataseg);
	  break;

	case TEXT_SEGMENT_END:
	  fold_segment_end (&expld.textseg);
	  break;

	default:
	  FAIL ();
	  break;
	}
    }
}

/* Arithmetic operators, bitwise AND, bitwise OR and XOR keep the
   section of one of their operands only when the other operand is a
   plain number.  Losing the section when operating on two symbols,
   ie. a result of a plain number, is required for subtraction and
   XOR.  It's justifiable for the other operations on the grounds that
   adding, multiplying etc. two section relative values does not
   really make sense unless they are just treated as numbers.
   The same argument could be made for many expressions involving one
   symbol and a number.  For example, "1 << x" and "100 / x" probably
   should not be given the section of x.  The trouble is that if we
   fuss about such things the rules become complex and it is onerous
   to document ld expression evaluation.  */
static void
arith_result_section (const etree_value_type *lhs)
{
  if (expld.result.section == lhs->section)
    {
      if (expld.section == bfd_abs_section_ptr
	  && !config.sane_expr)
	/* Duplicate the insanity in exp_fold_tree_1 case etree_value.  */
	expld.result.section = bfd_abs_section_ptr;
      else
	expld.result.section = NULL;
    }
}

static void
fold_segment_align (seg_align_type *seg, etree_value_type *lhs)
{
  seg->relro = exp_seg_relro_start;
  if (expld.phase == lang_first_phase_enum
      || expld.section != bfd_abs_section_ptr)
    expld.result.valid_p = FALSE;
  else
    {
      bfd_vma maxpage = lhs->value;
      bfd_vma commonpage = expld.result.value;

      expld.result.value = align_n (expld.dot, maxpage);
      if (seg->phase == exp_seg_relro_adjust)
	expld.result.value = seg->base;
      else if (seg->phase == exp_seg_adjust)
	{
	  if (commonpage < maxpage)
	    expld.result.value += ((expld.dot + commonpage - 1)
				   & (maxpage - commonpage));
	}
      else
	{
	  expld.result.value += expld.dot & (maxpage - 1);
	  if (seg->phase == exp_seg_done)
	    {
	      /* OK.  */
	    }
	  else if (seg->phase == exp_seg_none)
	    {
	      seg->phase = exp_seg_align_seen;
	      seg->base = expld.result.value;
	      seg->pagesize = commonpage;
	      seg->maxpagesize = maxpage;
	      seg->relro_end = 0;
	    }
	  else
	    expld.result.valid_p = FALSE;
	}
    }
}

static void
fold_segment_relro_end (seg_align_type *seg, etree_value_type *lhs)
{
  /* Operands swapped!  XXX_SEGMENT_RELRO_END(offset,exp) has offset
     in expld.result and exp in lhs.  */
  seg->relro = exp_seg_relro_end;
  seg->relro_offset = expld.result.value;
  if (expld.phase == lang_first_phase_enum
      || expld.section != bfd_abs_section_ptr)
    expld.result.valid_p = FALSE;
  else if (seg->phase == exp_seg_align_seen
	   || seg->phase == exp_seg_adjust
	   || seg->phase == exp_seg_relro_adjust
	   || seg->phase == exp_seg_done)
    {
      if (seg->phase == exp_seg_align_seen
	  || seg->phase == exp_seg_relro_adjust)
	seg->relro_end = lhs->value + expld.result.value;

      if (seg->phase == exp_seg_relro_adjust
	  && (seg->relro_end & (seg->pagesize - 1)))
	{
	  seg->relro_end += seg->pagesize - 1;
	  seg->relro_end &= ~(seg->pagesize - 1);
	  expld.result.value = seg->relro_end - expld.result.value;
	}
      else
	expld.result.value = lhs->value;

      if (seg->phase == exp_seg_align_seen)
	seg->phase = exp_seg_relro_seen;
    }
  else
    expld.result.valid_p = FALSE;
}

static void
fold_binary (etree_type *tree)
{
  etree_value_type lhs;
  exp_fold_tree_1 (tree->binary.lhs);

  /* The SEGMENT_START operator is special because its first
     operand is a string, not the name of a symbol.  Note that the
     operands have been swapped, so binary.lhs is second (default)
     operand, binary.rhs is first operand.  */
  if (expld.result.valid_p && tree->type.node_code == SEGMENT_START)
    {
      const char *segment_name;
      segment_type *seg;

      /* Check to see if the user has overridden the default
	 value.  */
      segment_name = tree->binary.rhs->name.name;
      for (seg = segments; seg; seg = seg->next)
	if (strcmp (seg->name, segment_name) == 0)
	  {
	    if (!seg->used
		&& config.magic_demand_paged
		&& (seg->value % config.maxpagesize) != 0)
	      einfo (_("%P: warning: address of `%s' "
		       "isn't multiple of maximum page size\n"),
		     segment_name);
	    seg->used = TRUE;
	    new_rel_from_abs (seg->value);
	    break;
	  }
      return;
    }

  lhs = expld.result;
  exp_fold_tree_1 (tree->binary.rhs);
  expld.result.valid_p &= lhs.valid_p;

  if (expld.result.valid_p)
    {
      if (lhs.section != expld.result.section)
	{
	  /* If the values are from different sections, and neither is
	     just a number, make both the source arguments absolute.  */
	  if (expld.result.section != NULL
	      && lhs.section != NULL)
	    {
	      make_abs ();
	      lhs.value += lhs.section->vma;
	      lhs.section = bfd_abs_section_ptr;
	    }

	  /* If the rhs is just a number, keep the lhs section.  */
	  else if (expld.result.section == NULL)
	    {
	      expld.result.section = lhs.section;
	      /* Make this NULL so that we know one of the operands
		 was just a number, for later tests.  */
	      lhs.section = NULL;
	    }
	}
      /* At this point we know that both operands have the same
	 section, or at least one of them is a plain number.  */

      switch (tree->type.node_code)
	{
#define BOP(x, y) \
	case x:							\
	  expld.result.value = lhs.value y expld.result.value;	\
	  arith_result_section (&lhs);				\
	  break;

	  /* Comparison operators, logical AND, and logical OR always
	     return a plain number.  */
#define BOPN(x, y) \
	case x:							\
	  expld.result.value = lhs.value y expld.result.value;	\
	  expld.result.section = NULL;				\
	  break;

	  BOP ('+', +);
	  BOP ('*', *);
	  BOP ('-', -);
	  BOP (LSHIFT, <<);
	  BOP (RSHIFT, >>);
	  BOP ('&', &);
	  BOP ('^', ^);
	  BOP ('|', |);
	  BOPN (EQ, ==);
	  BOPN (NE, !=);
	  BOPN ('<', <);
	  BOPN ('>', >);
	  BOPN (LE, <=);
	  BOPN (GE, >=);
	  BOPN (ANDAND, &&);
	  BOPN (OROR, ||);

	case '%':
	  if (expld.result.value != 0)
	    expld.result.value = ((bfd_signed_vma) lhs.value
				  % (bfd_signed_vma) expld.result.value);
	  else if (expld.phase != lang_mark_phase_enum)
	    einfo (_("%F%S %% by zero\n"), tree->binary.rhs);
	  arith_result_section (&lhs);
	  break;

	case '/':
	  if (expld.result.value != 0)
	    expld.result.value = ((bfd_signed_vma) lhs.value
				  / (bfd_signed_vma) expld.result.value);
	  else if (expld.phase != lang_mark_phase_enum)
	    einfo (_("%F%S / by zero\n"), tree->binary.rhs);
	  arith_result_section (&lhs);
	  break;

	case MAX_K:
	  if (lhs.value > expld.result.value)
	    expld.result.value = lhs.value;
	  break;

	case MIN_K:
	  if (lhs.value < expld.result.value)
	    expld.result.value = lhs.value;
	  break;

	case ALIGN_K:
	  expld.result.value = align_n (lhs.value, expld.result.value);
	  break;

	case DATA_SEGMENT_ALIGN:
	  fold_segment_align (&expld.dataseg, &lhs);
	  break;

	case DATA_SEGMENT_RELRO_END:
	  fold_segment_relro_end (&expld.dataseg, &lhs);
	  break;

	case TEXT_SEGMENT_ALIGN:
	  fold_segment_align (&expld.textseg, &lhs);
	  break;

	case TEXT_SEGMENT_RELRO_END:
	  fold_segment_relro_end (&expld.textseg, &lhs);
	  break;

	default:
	  FAIL ();
	}
    }
}

static void
fold_trinary (etree_type *tree)
{
  struct bfd_link_hash_entry *save = expld.assign_src;

  exp_fold_tree_1 (tree->trinary.cond);
  expld.assign_src = save;
  if (expld.result.valid_p)
    exp_fold_tree_1 (expld.result.value
		     ? tree->trinary.lhs
		     : tree->trinary.rhs);
}

static void
fold_name (etree_type *tree)
{
  struct bfd_link_hash_entry *h;
  struct definedness_hash_entry *def;

  memset (&expld.result, 0, sizeof (expld.result));

  switch (tree->type.node_code)
    {
    case SIZEOF_HEADERS:
      if (expld.phase != lang_first_phase_enum)
	{
	  bfd_vma hdr_size = 0;
	  /* Don't find the real header size if only marking sections;
	     The bfd function may cache incorrect data.  */
	  if (expld.phase != lang_mark_phase_enum)
	    hdr_size = bfd_sizeof_headers (link_info.output_bfd, &link_info);
	  new_number (hdr_size);
	}
      break;

    case DEFINED:
      h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
					&link_info,
					tree->name.name,
					FALSE, FALSE, TRUE);
      new_number (h != NULL
		  && (h->type == bfd_link_hash_defined
		      || h->type == bfd_link_hash_defweak
		      || h->type == bfd_link_hash_common)
		  && (!h->ldscript_def
		      || (def = symbol_defined (tree->name.name)) == NULL
		      || def->by_object
		      || def->iteration == (lang_statement_iteration & 255)));
      break;

    case NAME:
      if (expld.assign_name != NULL
	  && strcmp (expld.assign_name, tree->name.name) == 0)
	{
	  /* Self-assignment is only allowed for absolute symbols
	     defined in a linker script.  */
	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
					    &link_info,
					    tree->name.name,
					    FALSE, FALSE, TRUE);
	  if (!(h != NULL
		&& (h->type == bfd_link_hash_defined
		    || h->type == bfd_link_hash_defweak)
		&& h->u.def.section == bfd_abs_section_ptr
		&& (def = symbol_defined (tree->name.name)) != NULL
		&& def->iteration == (lang_statement_iteration & 255)))
	    expld.assign_name = NULL;
	}
      if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
	new_rel_from_abs (expld.dot);
      else
	{
	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
					    &link_info,
					    tree->name.name,
					    TRUE, FALSE, TRUE);
	  if (!h)
	    einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
	  else if (h->type == bfd_link_hash_defined
		   || h->type == bfd_link_hash_defweak)
	    {
	      asection *output_section;

	      output_section = h->u.def.section->output_section;
	      if (output_section == NULL)
		{
		  if (expld.phase <= lang_mark_phase_enum)
		    new_rel (h->u.def.value, h->u.def.section);
		  else
		    einfo (_("%X%S: unresolvable symbol `%s'"
			     " referenced in expression\n"),
			   tree, tree->name.name);
		}
	      else if (output_section == bfd_abs_section_ptr
		       && (expld.section != bfd_abs_section_ptr
			   || config.sane_expr))
		new_number (h->u.def.value + h->u.def.section->output_offset);
	      else
		new_rel (h->u.def.value + h->u.def.section->output_offset,
			 output_section);
	    }
	  else if (expld.phase == lang_final_phase_enum
		   || (expld.phase != lang_mark_phase_enum
		       && expld.assigning_to_dot))
	    einfo (_("%F%S: undefined symbol `%s'"
		     " referenced in expression\n"),
		   tree, tree->name.name);
	  else if (h->type == bfd_link_hash_new)
	    {
	      h->type = bfd_link_hash_undefined;
	      h->u.undef.abfd = NULL;
	      if (h->u.undef.next == NULL && h != link_info.hash->undefs_tail)
		bfd_link_add_undef (link_info.hash, h);
	    }
	  if (expld.assign_src == NULL)
	    expld.assign_src = h;
	  else
	    expld.assign_src = (struct bfd_link_hash_entry *) 0 - 1;
	}
      break;

    case ADDR:
      if (expld.phase != lang_first_phase_enum)
	{
	  lang_output_section_statement_type *os;

	  os = lang_output_section_find (tree->name.name);
	  if (os == NULL)
	    {
	      if (expld.phase == lang_final_phase_enum)
		einfo (_("%F%S: undefined section `%s'"
			 " referenced in expression\n"),
		       tree, tree->name.name);
	    }
	  else if (os->processed_vma)
	    new_rel (0, os->bfd_section);
	}
      break;

    case LOADADDR:
      if (expld.phase != lang_first_phase_enum)
	{
	  lang_output_section_statement_type *os;

	  os = lang_output_section_find (tree->name.name);
	  if (os == NULL)
	    {
	      if (expld.phase == lang_final_phase_enum)
		einfo (_("%F%S: undefined section `%s'"
			 " referenced in expression\n"),
		       tree, tree->name.name);
	    }
	  else if (os->processed_lma)
	    {
	      if (os->load_base == NULL)
		new_abs (os->bfd_section->lma);
	      else
		{
		  exp_fold_tree_1 (os->load_base);
		  if (expld.result.valid_p)
		    make_abs ();
		}
	    }
	}
      break;

    case SIZEOF:
    case ALIGNOF:
      if (expld.phase != lang_first_phase_enum)
	{
	  lang_output_section_statement_type *os;

	  os = lang_output_section_find (tree->name.name);
	  if (os == NULL)
	    {
	      if (expld.phase == lang_final_phase_enum)
		einfo (_("%F%S: undefined section `%s'"
			 " referenced in expression\n"),
		       tree, tree->name.name);
	      new_number (0);
	    }
	  else if (os->bfd_section != NULL)
	    {
	      bfd_vma val;

	      if (tree->type.node_code == SIZEOF)
		val = (os->bfd_section->size
		       / bfd_octets_per_byte (link_info.output_bfd));
	      else
		val = (bfd_vma)1 << os->bfd_section->alignment_power;

	      new_number (val);
	    }
	  else
	    new_number (0);
	}
      break;

    case LENGTH:
      {
      if (expld.phase != lang_first_phase_enum)
	{
	  lang_memory_region_type *mem;

	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
	  if (mem != NULL)
	    new_number (mem->length);
	  else
	    einfo (_("%F%S: undefined MEMORY region `%s'"
		     " referenced in expression\n"),
		   tree, tree->name.name);
	}
      }
      break;

    case ORIGIN:
      if (expld.phase != lang_first_phase_enum)
	{
	  lang_memory_region_type *mem;

	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
	  if (mem != NULL)
	    new_rel_from_abs (mem->origin);
	  else
	    einfo (_("%F%S: undefined MEMORY region `%s'"
		     " referenced in expression\n"),
		   tree, tree->name.name);
	}
      break;

    case CONSTANT:
      if (strcmp (tree->name.name, "MAXPAGESIZE") == 0)
	new_number (config.maxpagesize);
      else if (strcmp (tree->name.name, "COMMONPAGESIZE") == 0)
	new_number (config.commonpagesize);
      else
	einfo (_("%F%S: unknown constant `%s' referenced in expression\n"),
	       tree, tree->name.name);
      break;

    default:
      FAIL ();
      break;
    }
}

/* Return true if TREE is '.'.  */

static bfd_boolean
is_dot (const etree_type *tree)
{
  return (tree->type.node_class == etree_name
	  && tree->type.node_code == NAME
	  && tree->name.name[0] == '.'
	  && tree->name.name[1] == 0);
}

/* Return true if TREE is a constant equal to VAL.  */

static bfd_boolean
is_value (const etree_type *tree, bfd_vma val)
{
  return (tree->type.node_class == etree_value
	  && tree->value.value == val);
}

/* Return true if TREE is an absolute symbol equal to VAL defined in
   a linker script.  */

static bfd_boolean
is_sym_value (const etree_type *tree, bfd_vma val)
{
  struct bfd_link_hash_entry *h;
  struct definedness_hash_entry *def;

  return (tree->type.node_class == etree_name
	  && tree->type.node_code == NAME
	  && (def = symbol_defined (tree->name.name)) != NULL
	  && def->iteration == (lang_statement_iteration & 255)
	  && (h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
						&link_info,
						tree->name.name,
						FALSE, FALSE, TRUE)) != NULL
	  && h->ldscript_def
	  && h->type == bfd_link_hash_defined
	  && h->u.def.section == bfd_abs_section_ptr
	  && h->u.def.value == val);
}

/* Return true if TREE is ". != 0".  */

static bfd_boolean
is_dot_ne_0 (const etree_type *tree)
{
  return (tree->type.node_class == etree_binary
	  && tree->type.node_code == NE
	  && is_dot (tree->binary.lhs)
	  && is_value (tree->binary.rhs, 0));
}

/* Return true if TREE is ". = . + 0" or ". = . + sym" where sym is an
   absolute constant with value 0 defined in a linker script.  */

static bfd_boolean
is_dot_plus_0 (const etree_type *tree)
{
  return (tree->type.node_class == etree_binary
	  && tree->type.node_code == '+'
	  && is_dot (tree->binary.lhs)
	  && (is_value (tree->binary.rhs, 0)
	      || is_sym_value (tree->binary.rhs, 0)));
}

/* Return true if TREE is "ALIGN (. != 0 ? some_expression : 1)".  */

static bfd_boolean
is_align_conditional (const etree_type *tree)
{
  if (tree->type.node_class == etree_unary
      && tree->type.node_code == ALIGN_K)
    {
      tree = tree->unary.child;
      return (tree->type.node_class == etree_trinary
	      && is_dot_ne_0 (tree->trinary.cond)
	      && is_value (tree->trinary.rhs, 1));
    }
  return FALSE;
}

static void
exp_fold_tree_1 (etree_type *tree)
{
  if (tree == NULL)
    {
      memset (&expld.result, 0, sizeof (expld.result));
      return;
    }

  switch (tree->type.node_class)
    {
    case etree_value:
      if (expld.section == bfd_abs_section_ptr
	  && !config.sane_expr)
	new_abs (tree->value.value);
      else
	new_number (tree->value.value);
      expld.result.str = tree->value.str;
      break;

    case etree_rel:
      if (expld.phase != lang_first_phase_enum)
	{
	  asection *output_section = tree->rel.section->output_section;
	  new_rel (tree->rel.value + tree->rel.section->output_offset,
		   output_section);
	}
      else
	memset (&expld.result, 0, sizeof (expld.result));
      break;

    case etree_assert:
      exp_fold_tree_1 (tree->assert_s.child);
      if (expld.phase == lang_final_phase_enum && !expld.result.value)
	einfo ("%X%P: %s\n", tree->assert_s.message);
      break;

    case etree_unary:
      fold_unary (tree);
      break;

    case etree_binary:
      fold_binary (tree);
      break;

    case etree_trinary:
      fold_trinary (tree);
      break;

    case etree_assign:
    case etree_provide:
    case etree_provided:
      if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
	{
	  if (tree->type.node_class != etree_assign)
	    einfo (_("%F%S can not PROVIDE assignment to"
		     " location counter\n"), tree);
	  if (expld.phase != lang_first_phase_enum)
	    {
	      /* Notify the folder that this is an assignment to dot.  */
	      expld.assigning_to_dot = TRUE;
	      exp_fold_tree_1 (tree->assign.src);
	      expld.assigning_to_dot = FALSE;

	      /* If we are assigning to dot inside an output section
		 arrange to keep the section, except for certain
		 expressions that evaluate to zero.  We ignore . = 0,
		 . = . + 0, and . = ALIGN (. != 0 ? expr : 1).
		 We can't ignore all expressions that evaluate to zero
		 because an otherwise empty section might have padding
		 added by an alignment expression that changes with
		 relaxation.  Such a section might have zero size
		 before relaxation and so be stripped incorrectly.  */
	      if (expld.phase == lang_mark_phase_enum
		  && expld.section != bfd_abs_section_ptr
		  && expld.section != bfd_und_section_ptr
		  && !(expld.result.valid_p
		       && expld.result.value == 0
		       && (is_value (tree->assign.src, 0)
			   || is_sym_value (tree->assign.src, 0)
			   || is_dot_plus_0 (tree->assign.src)
			   || is_align_conditional (tree->assign.src))))
		expld.section->flags |= SEC_KEEP;

	      if (!expld.result.valid_p
		  || expld.section == bfd_und_section_ptr)
		{
		  if (expld.phase != lang_mark_phase_enum)
		    einfo (_("%F%S invalid assignment to"
			     " location counter\n"), tree);
		}
	      else if (expld.dotp == NULL)
		einfo (_("%F%S assignment to location counter"
			 " invalid outside of SECTIONS\n"), tree);

	      /* After allocation, assignment to dot should not be
		 done inside an output section since allocation adds a
		 padding statement that effectively duplicates the
		 assignment.  */
	      else if (expld.phase <= lang_allocating_phase_enum
		       || expld.section == bfd_abs_section_ptr)
		{
		  bfd_vma nextdot;

		  nextdot = expld.result.value;
		  if (expld.result.section != NULL)
		    nextdot += expld.result.section->vma;
		  else
		    nextdot += expld.section->vma;
		  if (nextdot < expld.dot
		      && expld.section != bfd_abs_section_ptr)
		    einfo (_("%F%S cannot move location counter backwards"
			     " (from %V to %V)\n"),
			   tree, expld.dot, nextdot);
		  else
		    {
		      expld.dot = nextdot;
		      *expld.dotp = nextdot;
		    }
		}
	    }
	  else
	    memset (&expld.result, 0, sizeof (expld.result));
	}
      else
	{
	  struct bfd_link_hash_entry *h = NULL;

	  if (tree->type.node_class == etree_provide)
	    {
	      h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
					FALSE, FALSE, TRUE);
	      if (h == NULL
		  || !(h->type == bfd_link_hash_new
		       || h->type == bfd_link_hash_undefined
		       || h->type == bfd_link_hash_undefweak
		       || h->linker_def))
		{
		  /* Do nothing.  The symbol was never referenced, or
		     was defined in some object file.  Note that
		     undefweak symbols are defined by PROVIDE.  This
		     is to support glibc use of __rela_iplt_start and
		     similar weak references.  */
		  break;
		}
	    }

	  expld.assign_name = tree->assign.dst;
	  expld.assign_src = NULL;
	  exp_fold_tree_1 (tree->assign.src);
	  /* expld.assign_name remaining equal to tree->assign.dst
	     below indicates the evaluation of tree->assign.src did
	     not use the value of tree->assign.dst.  We don't allow
	     self assignment until the final phase for two reasons:
	     1) Expressions are evaluated multiple times.  With
	     relaxation, the number of times may vary.
	     2) Section relative symbol values cannot be correctly
	     converted to absolute values, as is required by many
	     expressions, until final section sizing is complete.  */
	  if ((expld.result.valid_p
	       && (expld.phase == lang_final_phase_enum
		   || expld.assign_name != NULL))
	      || (expld.phase <= lang_mark_phase_enum
		  && tree->type.node_class == etree_assign
		  && tree->assign.defsym))
	    {
	      if (h == NULL)
		{
		  h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
					    TRUE, FALSE, TRUE);
		  if (h == NULL)
		    einfo (_("%P%F:%s: hash creation failed\n"),
			   tree->assign.dst);
		}

	      if (expld.result.section == NULL)
		expld.result.section = expld.section;
	      if (!update_definedness (tree->assign.dst, h) && 0)
		{
		  /* Symbol was already defined.  For now this error
		     is disabled because it causes failures in the ld
		     testsuite: ld-elf/var1, ld-scripts/defined5, and
		     ld-scripts/pr14962.  Some of these no doubt
		     reflect scripts used in the wild.  */
		  (*link_info.callbacks->multiple_definition)
		    (&link_info, h, link_info.output_bfd,
		     expld.result.section, expld.result.value);
		}
	      h->type = bfd_link_hash_defined;
	      h->u.def.value = expld.result.value;
	      h->u.def.section = expld.result.section;
	      h->linker_def = ! tree->assign.type.lineno;
	      h->ldscript_def = 1;
	      if (tree->type.node_class == etree_provide)
		tree->type.node_class = etree_provided;

	      /* Copy the symbol type if this is an expression only
		 referencing a single symbol.  (If the expression
		 contains ternary conditions, ignoring symbols on
		 false branches.)  */
	      if (expld.result.valid_p
		  && expld.assign_src != NULL
		  && expld.assign_src != (struct bfd_link_hash_entry *) 0 - 1)
		bfd_copy_link_hash_symbol_type (link_info.output_bfd, h,
						expld.assign_src);
	    }
	  else if (expld.phase == lang_final_phase_enum)
	    {
	      h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
					FALSE, FALSE, TRUE);
	      if (h != NULL
		  && h->type == bfd_link_hash_new)
		h->type = bfd_link_hash_undefined;
	    }
	  expld.assign_name = NULL;
	}
      break;

    case etree_name:
      fold_name (tree);
      break;

    default:
      FAIL ();
      memset (&expld.result, 0, sizeof (expld.result));
      break;
    }
}

void
exp_fold_tree (etree_type *tree, asection *current_section, bfd_vma *dotp)
{
  expld.rel_from_abs = FALSE;
  expld.dot = *dotp;
  expld.dotp = dotp;
  expld.section = current_section;
  exp_fold_tree_1 (tree);
}

void
exp_fold_tree_no_dot (etree_type *tree)
{
  expld.rel_from_abs = FALSE;
  expld.dot = 0;
  expld.dotp = NULL;
  expld.section = bfd_abs_section_ptr;
  exp_fold_tree_1 (tree);
}

static void
exp_value_fold (etree_type *tree)
{
  exp_fold_tree_no_dot (tree);
  if (expld.result.valid_p)
    {
      tree->type.node_code = INT;
      tree->value.value = expld.result.value;
      tree->value.str = NULL;
      tree->type.node_class = etree_value;
    }
}

#define MAX(a, b) ((a) > (b) ? (a) : (b))

etree_type *
exp_binop (int code, etree_type *lhs, etree_type *rhs)
{
  etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->binary),
						      sizeof (new_e->value)));
  new_e->type.node_code = code;
  new_e->type.filename = lhs->type.filename;
  new_e->type.lineno = lhs->type.lineno;
  new_e->binary.lhs = lhs;
  new_e->binary.rhs = rhs;
  new_e->type.node_class = etree_binary;
  if (lhs->type.node_class == etree_value
      && rhs->type.node_class == etree_value
      && code != ALIGN_K
      && code != DATA_SEGMENT_ALIGN
      && code != DATA_SEGMENT_RELRO_END)
    exp_value_fold (new_e);
  return new_e;
}

etree_type *
exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
{
  etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->trinary),
						      sizeof (new_e->value)));
  new_e->type.node_code = code;
  new_e->type.filename = cond->type.filename;
  new_e->type.lineno = cond->type.lineno;
  new_e->trinary.lhs = lhs;
  new_e->trinary.cond = cond;
  new_e->trinary.rhs = rhs;
  new_e->type.node_class = etree_trinary;
  if (cond->type.node_class == etree_value
      && lhs->type.node_class == etree_value
      && rhs->type.node_class == etree_value)
    exp_value_fold (new_e);
  return new_e;
}

etree_type *
exp_unop (int code, etree_type *child)
{
  etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->unary),
						      sizeof (new_e->value)));
  new_e->unary.type.node_code = code;
  new_e->unary.type.filename = child->type.filename;
  new_e->unary.type.lineno = child->type.lineno;
  new_e->unary.child = child;
  new_e->unary.type.node_class = etree_unary;
  if (child->type.node_class == etree_value
      && code != ALIGN_K
      && code != ABSOLUTE
      && code != NEXT
      && code != DATA_SEGMENT_END
      && code != TEXT_SEGMENT_END)
    exp_value_fold (new_e);
  return new_e;
}

etree_type *
exp_nameop (int code, const char *name)
{
  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->name));

  new_e->name.type.node_code = code;
  new_e->name.type.filename = ldlex_filename ();
  new_e->name.type.lineno = lineno;
  new_e->name.name = name;
  new_e->name.type.node_class = etree_name;
  return new_e;

}

static etree_type *
exp_assop (const char *dst,
	   etree_type *src,
	   enum node_tree_enum class,
	   bfd_boolean defsym,
	   bfd_boolean hidden)
{
  etree_type *n;

  n = (etree_type *) stat_alloc (sizeof (n->assign));
  n->assign.type.node_code = '=';
  n->assign.type.filename = src->type.filename;
  n->assign.type.lineno = src->type.lineno;
  n->assign.type.node_class = class;
  n->assign.src = src;
  n->assign.dst = dst;
  n->assign.defsym = defsym;
  n->assign.hidden = hidden;
  return n;
}

/* Handle linker script assignments and HIDDEN.  */

etree_type *
exp_assign (const char *dst, etree_type *src, bfd_boolean hidden)
{
  return exp_assop (dst, src, etree_assign, FALSE, hidden);
}

/* Handle --defsym command-line option.  */

etree_type *
exp_defsym (const char *dst, etree_type *src)
{
  return exp_assop (dst, src, etree_assign, TRUE, FALSE);
}

/* Handle PROVIDE.  */

etree_type *
exp_provide (const char *dst, etree_type *src, bfd_boolean hidden)
{
  return exp_assop (dst, src, etree_provide, FALSE, hidden);
}

/* Handle ASSERT.  */

etree_type *
exp_assert (etree_type *exp, const char *message)
{
  etree_type *n;

  n = (etree_type *) stat_alloc (sizeof (n->assert_s));
  n->assert_s.type.node_code = '!';
  n->assert_s.type.filename = exp->type.filename;
  n->assert_s.type.lineno = exp->type.lineno;
  n->assert_s.type.node_class = etree_assert;
  n->assert_s.child = exp;
  n->assert_s.message = message;
  return n;
}

void
exp_print_tree (etree_type *tree)
{
  bfd_boolean function_like;

  if (config.map_file == NULL)
    config.map_file = stderr;

  if (tree == NULL)
    {
      minfo ("NULL TREE\n");
      return;
    }

  switch (tree->type.node_class)
    {
    case etree_value:
      minfo ("0x%v", tree->value.value);
      return;
    case etree_rel:
      if (tree->rel.section->owner != NULL)
	minfo ("%B:", tree->rel.section->owner);
      minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
      return;
    case etree_assign:
      fputs (tree->assign.dst, config.map_file);
      exp_print_token (tree->type.node_code, TRUE);
      exp_print_tree (tree->assign.src);
      break;
    case etree_provide:
    case etree_provided:
      fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
      exp_print_tree (tree->assign.src);
      fputc (')', config.map_file);
      break;
    case etree_binary:
      function_like = FALSE;
      switch (tree->type.node_code)
	{
	case MAX_K:
	case MIN_K:
	case ALIGN_K:
	case DATA_SEGMENT_ALIGN:
	case DATA_SEGMENT_RELRO_END:
	  function_like = TRUE;
	  break;
	case SEGMENT_START:
	  /* Special handling because arguments are in reverse order and
	     the segment name is quoted.  */
	  exp_print_token (tree->type.node_code, FALSE);
	  fputs (" (\"", config.map_file);
	  exp_print_tree (tree->binary.rhs);
	  fputs ("\", ", config.map_file);
	  exp_print_tree (tree->binary.lhs);
	  fputc (')', config.map_file);
	  return;
	}
      if (function_like)
	{
	  exp_print_token (tree->type.node_code, FALSE);
	  fputc (' ', config.map_file);
	}
      fputc ('(', config.map_file);
      exp_print_tree (tree->binary.lhs);
      if (function_like)
	fprintf (config.map_file, ", ");
      else
	exp_print_token (tree->type.node_code, TRUE);
      exp_print_tree (tree->binary.rhs);
      fputc (')', config.map_file);
      break;
    case etree_trinary:
      exp_print_tree (tree->trinary.cond);
      fputc ('?', config.map_file);
      exp_print_tree (tree->trinary.lhs);
      fputc (':', config.map_file);
      exp_print_tree (tree->trinary.rhs);
      break;
    case etree_unary:
      exp_print_token (tree->unary.type.node_code, FALSE);
      if (tree->unary.child)
	{
	  fprintf (config.map_file, " (");
	  exp_print_tree (tree->unary.child);
	  fputc (')', config.map_file);
	}
      break;

    case etree_assert:
      fprintf (config.map_file, "ASSERT (");
      exp_print_tree (tree->assert_s.child);
      fprintf (config.map_file, ", %s)", tree->assert_s.message);
      break;

    case etree_name:
      if (tree->type.node_code == NAME)
	fputs (tree->name.name, config.map_file);
      else
	{
	  exp_print_token (tree->type.node_code, FALSE);
	  if (tree->name.name)
	    fprintf (config.map_file, " (%s)", tree->name.name);
	}
      break;
    default:
      FAIL ();
      break;
    }
}

bfd_vma
exp_get_vma (etree_type *tree, bfd_vma def, char *name)
{
  if (tree != NULL)
    {
      exp_fold_tree_no_dot (tree);
      if (expld.result.valid_p)
	return expld.result.value;
      else if (name != NULL && expld.phase != lang_mark_phase_enum)
	einfo (_("%F%S: nonconstant expression for %s\n"),
	       tree, name);
    }
  return def;
}

int
exp_get_value_int (etree_type *tree, int def, char *name)
{
  return exp_get_vma (tree, def, name);
}

fill_type *
exp_get_fill (etree_type *tree, fill_type *def, char *name)
{
  fill_type *fill;
  size_t len;
  unsigned int val;

  if (tree == NULL)
    return def;

  exp_fold_tree_no_dot (tree);
  if (!expld.result.valid_p)
    {
      if (name != NULL && expld.phase != lang_mark_phase_enum)
	einfo (_("%F%S: nonconstant expression for %s\n"),
	       tree, name);
      return def;
    }

  if (expld.result.str != NULL && (len = strlen (expld.result.str)) != 0)
    {
      unsigned char *dst;
      unsigned char *s;
      fill = (fill_type *) xmalloc ((len + 1) / 2 + sizeof (*fill) - 1);
      fill->size = (len + 1) / 2;
      dst = fill->data;
      s = (unsigned char *) expld.result.str;
      val = 0;
      do
	{
	  unsigned int digit;

	  digit = *s++ - '0';
	  if (digit > 9)
	    digit = (digit - 'A' + '0' + 10) & 0xf;
	  val <<= 4;
	  val += digit;
	  --len;
	  if ((len & 1) == 0)
	    {
	      *dst++ = val;
	      val = 0;
	    }
	}
      while (len != 0);
    }
  else
    {
      fill = (fill_type *) xmalloc (4 + sizeof (*fill) - 1);
      val = expld.result.value;
      fill->data[0] = (val >> 24) & 0xff;
      fill->data[1] = (val >> 16) & 0xff;
      fill->data[2] = (val >>  8) & 0xff;
      fill->data[3] = (val >>  0) & 0xff;
      fill->size = 4;
    }
  return fill;
}

bfd_vma
exp_get_abs_int (etree_type *tree, int def, char *name)
{
  if (tree != NULL)
    {
      exp_fold_tree_no_dot (tree);

      if (expld.result.valid_p)
	{
	  if (expld.result.section != NULL)
	    expld.result.value += expld.result.section->vma;
	  return expld.result.value;
	}
      else if (name != NULL && expld.phase != lang_mark_phase_enum)
	{
	  einfo (_("%F%S: nonconstant expression for %s\n"),
		 tree, name);
	}
    }
  return def;
}

static bfd_vma
align_n (bfd_vma value, bfd_vma align)
{
  if (align <= 1)
    return value;

  value = (value + align - 1) / align;
  return value * align;
}

void
ldexp_init (void)
{
  /* The value "13" is ad-hoc, somewhat related to the expected number of
     assignments in a linker script.  */
  if (!bfd_hash_table_init_n (&definedness_table,
			      definedness_newfunc,
			      sizeof (struct definedness_hash_entry),
			      13))
    einfo (_("%P%F: can not create hash table: %E\n"));
}

/* Convert absolute symbols defined by a script from "dot" (also
   SEGMENT_START or ORIGIN) outside of an output section statement,
   to section relative.  */

static bfd_boolean
set_sym_sections (struct bfd_hash_entry *bh, void *inf ATTRIBUTE_UNUSED)
{
  struct definedness_hash_entry *def = (struct definedness_hash_entry *) bh;
  if (def->final_sec != bfd_abs_section_ptr)
    {
      struct bfd_link_hash_entry *h;
      h = bfd_link_hash_lookup (link_info.hash, bh->string,
				FALSE, FALSE, TRUE);
      if (h != NULL
	  && h->type == bfd_link_hash_defined
	  && h->u.def.section == bfd_abs_section_ptr)
	{
	  h->u.def.value -= def->final_sec->vma;
	  h->u.def.section = def->final_sec;
	}
    }
  return TRUE;
}

void
ldexp_finalize_syms (void)
{
  bfd_hash_traverse (&definedness_table, set_sym_sections, NULL);
}

void
ldexp_finish (void)
{
  bfd_hash_table_free (&definedness_table);
}