Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

   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
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
/* tc-crx.c -- Assembler code for the CRX CPU core.
   Copyright (C) 2004-2018 Free Software Foundation, Inc.

   Contributed by Tomer Levi, NSC, Israel.
   Originally written for GAS 2.12 by Tomer Levi, NSC, Israel.
   Updates, BFDizing, GNUifying and ELF support by Tomer Levi.

   This file is part of GAS, the GNU Assembler.

   GAS is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   GAS is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GAS; see the file COPYING.  If not, write to the
   Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "as.h"
#include "bfd_stdint.h"
#include "safe-ctype.h"
#include "dwarf2dbg.h"
#include "opcode/crx.h"
#include "elf/crx.h"

/* Word is considered here as a 16-bit unsigned short int.  */
#define WORD_SHIFT  16

/* Register is 4-bit size.  */
#define REG_SIZE   4

/* Maximum size of a single instruction (in words).  */
#define INSN_MAX_SIZE   3

/* Maximum bits which may be set in a `mask16' operand.  */
#define MAX_REGS_IN_MASK16  8

/* Utility macros for string comparison.  */
#define streq(a, b)           (strcmp (a, b) == 0)
#define strneq(a, b, c)       (strncmp (a, b, c) == 0)

/* Assign a number NUM, shifted by SHIFT bytes, into a location
   pointed by index BYTE of array 'output_opcode'.  */
#define CRX_PRINT(BYTE, NUM, SHIFT)   output_opcode[BYTE] |= (NUM << SHIFT)

/* Operand errors.  */
typedef enum
  {
    OP_LEGAL = 0,	/* Legal operand.  */
    OP_OUT_OF_RANGE,	/* Operand not within permitted range.  */
    OP_NOT_EVEN,	/* Operand is Odd number, should be even.  */
    OP_ILLEGAL_DISPU4,	/* Operand is not within DISPU4 range.  */
    OP_ILLEGAL_CST4,	/* Operand is not within CST4 range.  */
    OP_NOT_UPPER_64KB	/* Operand is not within the upper 64KB
			   (0xFFFF0000-0xFFFFFFFF).  */
  }
op_err;

/* Opcode mnemonics hash table.  */
static struct hash_control *crx_inst_hash;
/* CRX registers hash table.  */
static struct hash_control *reg_hash;
/* CRX coprocessor registers hash table.  */
static struct hash_control *copreg_hash;
/* Current instruction we're assembling.  */
static const inst *instruction;

/* Global variables.  */

/* Array to hold an instruction encoding.  */
static long output_opcode[2];

/* Nonzero means a relocatable symbol.  */
static int relocatable;

/* A copy of the original instruction (used in error messages).  */
static char ins_parse[MAX_INST_LEN];

/* The current processed argument number.  */
static int cur_arg_num;

/* Generic assembler global variables which must be defined by all targets.  */

/* Characters which always start a comment.  */
const char comment_chars[] = "#";

/* Characters which start a comment at the beginning of a line.  */
const char line_comment_chars[] = "#";

/* This array holds machine specific line separator characters.  */
const char line_separator_chars[] = ";";

/* Chars that can be used to separate mant from exp in floating point nums.  */
const char EXP_CHARS[] = "eE";

/* Chars that mean this number is a floating point constant as in 0f12.456  */
const char FLT_CHARS[] = "f'";

/* Target-specific multicharacter options, not const-declared at usage.  */
const char *md_shortopts = "";
struct option md_longopts[] =
{
  {NULL, no_argument, NULL, 0}
};
size_t md_longopts_size = sizeof (md_longopts);

/* This table describes all the machine specific pseudo-ops
   the assembler has to support.  The fields are:
   *** Pseudo-op name without dot.
   *** Function to call to execute this pseudo-op.
   *** Integer arg to pass to the function.  */

const pseudo_typeS md_pseudo_table[] =
{
  /* In CRX machine, align is in bytes (not a ptwo boundary).  */
  {"align", s_align_bytes, 0},
  {0, 0, 0}
};

/* CRX relaxation table.  */
const relax_typeS md_relax_table[] =
{
  /* bCC  */
  {0xfa, -0x100, 2, 1},			/*  8 */
  {0xfffe, -0x10000, 4, 2},		/* 16 */
  {0xfffffffe, -0xfffffffe, 6, 0},	/* 32 */

  /* bal  */
  {0xfffe, -0x10000, 4, 4},		/* 16 */
  {0xfffffffe, -0xfffffffe, 6, 0},	/* 32 */

  /* cmpbr/bcop  */
  {0xfe, -0x100, 4, 6},			/*  8 */
  {0xfffffe, -0x1000000, 6, 0}		/* 24 */
};

static void    reset_vars	        (char *);
static reg     get_register	        (char *);
static copreg  get_copregister	        (char *);
static argtype get_optype	        (operand_type);
static int     get_opbits	        (operand_type);
static int     get_opflags	        (operand_type);
static int     get_number_of_operands   (void);
static void    parse_operand	        (char *, ins *);
static int     gettrap		        (const char *);
static void    handle_LoadStor	        (const char *);
static int     get_cinv_parameters      (const char *);
static long    getconstant		(long, int);
static op_err  check_range		(long *, int, unsigned int, int);
static int     getreg_image	        (reg);
static void    parse_operands	        (ins *, char *);
static void    parse_insn	        (ins *, char *);
static void    print_operand	        (int, int, argument *);
static void    print_constant	        (int, int, argument *);
static int     exponent2scale	        (int);
static void    mask_reg		        (int, unsigned short *);
static void    process_label_constant   (char *, ins *);
static void    set_operand	        (char *, ins *);
static char *  preprocess_reglist       (char *, int *);
static int     assemble_insn	        (char *, ins *);
static void    print_insn	        (ins *);
static void    warn_if_needed		(ins *);
static int     adjust_if_needed		(ins *);

/* Return the bit size for a given operand.  */

static int
get_opbits (operand_type op)
{
  if (op < MAX_OPRD)
    return crx_optab[op].bit_size;
  else
    return 0;
}

/* Return the argument type of a given operand.  */

static argtype
get_optype (operand_type op)
{
  if (op < MAX_OPRD)
    return crx_optab[op].arg_type;
  else
    return nullargs;
}

/* Return the flags of a given operand.  */

static int
get_opflags (operand_type op)
{
  if (op < MAX_OPRD)
    return crx_optab[op].flags;
  else
    return 0;
}

/* Get the core processor register 'reg_name'.  */

static reg
get_register (char *reg_name)
{
  const reg_entry *rreg;

  rreg = (const reg_entry *) hash_find (reg_hash, reg_name);

  if (rreg != NULL)
    return rreg->value.reg_val;
  else
    return nullregister;
}

/* Get the coprocessor register 'copreg_name'.  */

static copreg
get_copregister (char *copreg_name)
{
  const reg_entry *coreg;

  coreg = (const reg_entry *) hash_find (copreg_hash, copreg_name);

  if (coreg != NULL)
    return coreg->value.copreg_val;
  else
    return nullcopregister;
}

/* Round up a section size to the appropriate boundary.  */

valueT
md_section_align (segT seg, valueT val)
{
  /* Round .text section to a multiple of 2.  */
  if (seg == text_section)
    return (val + 1) & ~1;
  return val;
}

/* Parse an operand that is machine-specific (remove '*').  */

void
md_operand (expressionS * exp)
{
  char c = *input_line_pointer;

  switch (c)
    {
    case '*':
      input_line_pointer++;
      expression (exp);
      break;
    default:
      break;
    }
}

/* Reset global variables before parsing a new instruction.  */

static void
reset_vars (char *op)
{
  cur_arg_num = relocatable = 0;
  memset (& output_opcode, '\0', sizeof (output_opcode));

  /* Save a copy of the original OP (used in error messages).  */
  strncpy (ins_parse, op, sizeof ins_parse - 1);
  ins_parse [sizeof ins_parse - 1] = 0;
}

/* This macro decides whether a particular reloc is an entry in a
   switch table.  It is used when relaxing, because the linker needs
   to know about all such entries so that it can adjust them if
   necessary.  */

#define SWITCH_TABLE(fix)				  \
  (   (fix)->fx_addsy != NULL				  \
   && (fix)->fx_subsy != NULL				  \
   && S_GET_SEGMENT ((fix)->fx_addsy) ==		  \
      S_GET_SEGMENT ((fix)->fx_subsy)			  \
   && S_GET_SEGMENT (fix->fx_addsy) != undefined_section  \
   && (   (fix)->fx_r_type == BFD_RELOC_CRX_NUM8	  \
       || (fix)->fx_r_type == BFD_RELOC_CRX_NUM16	  \
       || (fix)->fx_r_type == BFD_RELOC_CRX_NUM32))

/* See whether we need to force a relocation into the output file.
   This is used to force out switch and PC relative relocations when
   relaxing.  */

int
crx_force_relocation (fixS *fix)
{
  if (generic_force_reloc (fix) || SWITCH_TABLE (fix))
    return 1;

  return 0;
}

/* Generate a relocation entry for a fixup.  */

arelent *
tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS * fixP)
{
  arelent * reloc;

  reloc = XNEW (arelent);
  reloc->sym_ptr_ptr  = XNEW (asymbol *);
  *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixP->fx_addsy);
  reloc->address = fixP->fx_frag->fr_address + fixP->fx_where;
  reloc->addend = fixP->fx_offset;

  if (fixP->fx_subsy != NULL)
    {
      if (SWITCH_TABLE (fixP))
	{
	  /* Keep the current difference in the addend.  */
	  reloc->addend = (S_GET_VALUE (fixP->fx_addsy)
			   - S_GET_VALUE (fixP->fx_subsy) + fixP->fx_offset);

	  switch (fixP->fx_r_type)
	    {
	    case BFD_RELOC_CRX_NUM8:
	      fixP->fx_r_type = BFD_RELOC_CRX_SWITCH8;
	      break;
	    case BFD_RELOC_CRX_NUM16:
	      fixP->fx_r_type = BFD_RELOC_CRX_SWITCH16;
	      break;
	    case BFD_RELOC_CRX_NUM32:
	      fixP->fx_r_type = BFD_RELOC_CRX_SWITCH32;
	      break;
	    default:
	      abort ();
	      break;
	    }
	}
      else
	{
	  /* We only resolve difference expressions in the same section.  */
	  as_bad_where (fixP->fx_file, fixP->fx_line,
			_("can't resolve `%s' {%s section} - `%s' {%s section}"),
			fixP->fx_addsy ? S_GET_NAME (fixP->fx_addsy) : "0",
			segment_name (fixP->fx_addsy
				      ? S_GET_SEGMENT (fixP->fx_addsy)
				      : absolute_section),
			S_GET_NAME (fixP->fx_subsy),
			segment_name (S_GET_SEGMENT (fixP->fx_addsy)));
	}
    }

  gas_assert ((int) fixP->fx_r_type > 0);
  reloc->howto = bfd_reloc_type_lookup (stdoutput, fixP->fx_r_type);

  if (reloc->howto == (reloc_howto_type *) NULL)
    {
      as_bad_where (fixP->fx_file, fixP->fx_line,
		    _("internal error: reloc %d (`%s') not supported by object file format"),
		    fixP->fx_r_type,
		    bfd_get_reloc_code_name (fixP->fx_r_type));
      return NULL;
    }
  gas_assert (!fixP->fx_pcrel == !reloc->howto->pc_relative);

  return reloc;
}

/* Prepare machine-dependent frags for relaxation.  */

int
md_estimate_size_before_relax (fragS *fragp, asection *seg)
{
  /* If symbol is undefined or located in a different section,
     select the largest supported relocation.  */
  relax_substateT subtype;
  relax_substateT rlx_state[] = {0, 2,
				 3, 4,
				 5, 6};

  for (subtype = 0; subtype < ARRAY_SIZE (rlx_state); subtype += 2)
    {
      if (fragp->fr_subtype == rlx_state[subtype]
	  && (!S_IS_DEFINED (fragp->fr_symbol)
	      || seg != S_GET_SEGMENT (fragp->fr_symbol)))
	{
	  fragp->fr_subtype = rlx_state[subtype + 1];
	  break;
	}
    }

  if (fragp->fr_subtype >= ARRAY_SIZE (md_relax_table))
    abort ();

  return md_relax_table[fragp->fr_subtype].rlx_length;
}

void
md_convert_frag (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, fragS *fragP)
{
  /* 'opcode' points to the start of the instruction, whether
     we need to change the instruction's fixed encoding.  */
  char *opcode = fragP->fr_literal + fragP->fr_fix;
  bfd_reloc_code_real_type reloc;

  subseg_change (sec, 0);

  switch (fragP->fr_subtype)
    {
    case 0:
      reloc = BFD_RELOC_CRX_REL8;
      break;
    case 1:
      *opcode = 0x7e;
      reloc = BFD_RELOC_CRX_REL16;
      break;
    case 2:
      *opcode = 0x7f;
      reloc = BFD_RELOC_CRX_REL32;
      break;
    case 3:
      reloc = BFD_RELOC_CRX_REL16;
      break;
    case 4:
      *++opcode = 0x31;
      reloc = BFD_RELOC_CRX_REL32;
      break;
    case 5:
      reloc = BFD_RELOC_CRX_REL8_CMP;
      break;
    case 6:
      *++opcode = 0x31;
      reloc = BFD_RELOC_CRX_REL24;
      break;
    default:
      abort ();
      break;
    }

    fix_new (fragP, fragP->fr_fix,
	     bfd_get_reloc_size (bfd_reloc_type_lookup (stdoutput, reloc)),
	     fragP->fr_symbol, fragP->fr_offset, 1, reloc);
    fragP->fr_var = 0;
    fragP->fr_fix += md_relax_table[fragP->fr_subtype].rlx_length;
}

/* Process machine-dependent command line options.  Called once for
   each option on the command line that the machine-independent part of
   GAS does not understand.  */

int
md_parse_option (int c ATTRIBUTE_UNUSED, const char *arg ATTRIBUTE_UNUSED)
{
  return 0;
}

/* Machine-dependent usage-output.  */

void
md_show_usage (FILE *stream ATTRIBUTE_UNUSED)
{
  return;
}

const char *
md_atof (int type, char *litP, int *sizeP)
{
  return ieee_md_atof (type, litP, sizeP, target_big_endian);
}

/* Apply a fixS (fixup of an instruction or data that we didn't have
   enough info to complete immediately) to the data in a frag.
   Since linkrelax is nonzero and TC_LINKRELAX_FIXUP is defined to disable
   relaxation of debug sections, this function is called only when
   fixuping relocations of debug sections.  */

void
md_apply_fix (fixS *fixP, valueT *valP, segT seg)
{
  valueT val = * valP;
  char *buf = fixP->fx_frag->fr_literal + fixP->fx_where;
  fixP->fx_offset = 0;

  switch (fixP->fx_r_type)
    {
    case BFD_RELOC_CRX_NUM8:
      bfd_put_8 (stdoutput, (unsigned char) val, buf);
      break;
    case BFD_RELOC_CRX_NUM16:
      bfd_put_16 (stdoutput, val, buf);
      break;
    case BFD_RELOC_CRX_NUM32:
      bfd_put_32 (stdoutput, val, buf);
      break;
    default:
      /* We shouldn't ever get here because linkrelax is nonzero.  */
      abort ();
      break;
    }

  fixP->fx_done = 0;

  if (fixP->fx_addsy == NULL
      && fixP->fx_pcrel == 0)
    fixP->fx_done = 1;

  if (fixP->fx_pcrel == 1
      && fixP->fx_addsy != NULL
      && S_GET_SEGMENT (fixP->fx_addsy) == seg)
    fixP->fx_done = 1;
}

/* The location from which a PC relative jump should be calculated,
   given a PC relative reloc.  */

long
md_pcrel_from (fixS *fixp)
{
  return fixp->fx_frag->fr_address + fixp->fx_where;
}

/* This function is called once, at assembler startup time.  This should
   set up all the tables, etc that the MD part of the assembler needs.  */

void
md_begin (void)
{
  const char *hashret = NULL;
  int i = 0;

  /* Set up a hash table for the instructions.  */
  if ((crx_inst_hash = hash_new ()) == NULL)
    as_fatal (_("Virtual memory exhausted"));

  while (crx_instruction[i].mnemonic != NULL)
    {
      const char *mnemonic = crx_instruction[i].mnemonic;

      hashret = hash_insert (crx_inst_hash, mnemonic,
			     (void *) &crx_instruction[i]);

      if (hashret != NULL && *hashret != '\0')
	as_fatal (_("Can't hash `%s': %s\n"), crx_instruction[i].mnemonic,
		  *hashret == 0 ? _("(unknown reason)") : hashret);

      /* Insert unique names into hash table.  The CRX instruction set
	 has many identical opcode names that have different opcodes based
	 on the operands.  This hash table then provides a quick index to
	 the first opcode with a particular name in the opcode table.  */
      do
	{
	  ++i;
	}
      while (crx_instruction[i].mnemonic != NULL
	     && streq (crx_instruction[i].mnemonic, mnemonic));
    }

  /* Initialize reg_hash hash table.  */
  if ((reg_hash = hash_new ()) == NULL)
    as_fatal (_("Virtual memory exhausted"));

  {
    const reg_entry *regtab;

    for (regtab = crx_regtab;
	 regtab < (crx_regtab + NUMREGS); regtab++)
      {
	hashret = hash_insert (reg_hash, regtab->name, (void *) regtab);
	if (hashret)
	  as_fatal (_("Internal error: Can't hash %s: %s"),
		    regtab->name,
		    hashret);
      }
  }

  /* Initialize copreg_hash hash table.  */
  if ((copreg_hash = hash_new ()) == NULL)
    as_fatal (_("Virtual memory exhausted"));

  {
    const reg_entry *copregtab;

    for (copregtab = crx_copregtab; copregtab < (crx_copregtab + NUMCOPREGS);
	 copregtab++)
      {
	hashret = hash_insert (copreg_hash, copregtab->name,
			       (void *) copregtab);
	if (hashret)
	  as_fatal (_("Internal error: Can't hash %s: %s"),
		    copregtab->name,
		    hashret);
      }
  }
  /*  Set linkrelax here to avoid fixups in most sections.  */
  linkrelax = 1;
}

/* Process constants (immediate/absolute)
   and labels (jump targets/Memory locations).  */

static void
process_label_constant (char *str, ins * crx_ins)
{
  char *saved_input_line_pointer;
  argument *cur_arg = &crx_ins->arg[cur_arg_num];  /* Current argument.  */

  saved_input_line_pointer = input_line_pointer;
  input_line_pointer = str;

  expression (&crx_ins->exp);

  switch (crx_ins->exp.X_op)
    {
    case O_big:
    case O_absent:
      /* Missing or bad expr becomes absolute 0.  */
      as_bad (_("missing or invalid displacement expression `%s' taken as 0"),
	      str);
      crx_ins->exp.X_op = O_constant;
      crx_ins->exp.X_add_number = 0;
      crx_ins->exp.X_add_symbol = (symbolS *) 0;
      crx_ins->exp.X_op_symbol = (symbolS *) 0;
      /* Fall through.  */

    case O_constant:
      cur_arg->X_op = O_constant;
      cur_arg->constant = crx_ins->exp.X_add_number;
      break;

    case O_symbol:
    case O_subtract:
    case O_add:
      cur_arg->X_op = O_symbol;
      crx_ins->rtype = BFD_RELOC_NONE;
      relocatable = 1;

      switch (cur_arg->type)
	{
	case arg_cr:
          if (IS_INSN_TYPE (LD_STOR_INS_INC))
	    crx_ins->rtype = BFD_RELOC_CRX_REGREL12;
          else if (IS_INSN_TYPE (CSTBIT_INS)
		   || IS_INSN_TYPE (STOR_IMM_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_REGREL28;
          else
	    crx_ins->rtype = BFD_RELOC_CRX_REGREL32;
	  break;

	case arg_idxr:
	    crx_ins->rtype = BFD_RELOC_CRX_REGREL22;
	  break;

	case arg_c:
          if (IS_INSN_MNEMONIC ("bal") || IS_INSN_TYPE (DCR_BRANCH_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_REL16;
	  else if (IS_INSN_TYPE (BRANCH_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_REL8;
          else if (IS_INSN_TYPE (LD_STOR_INS) || IS_INSN_TYPE (STOR_IMM_INS)
		   || IS_INSN_TYPE (CSTBIT_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_ABS32;
	  else if (IS_INSN_TYPE (BRANCH_NEQ_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_REL4;
          else if (IS_INSN_TYPE (CMPBR_INS) || IS_INSN_TYPE (COP_BRANCH_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_REL8_CMP;
	  break;

	case arg_ic:
          if (IS_INSN_TYPE (ARITH_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_IMM32;
	  else if (IS_INSN_TYPE (ARITH_BYTE_INS))
	    crx_ins->rtype = BFD_RELOC_CRX_IMM16;
	  break;
	default:
	  break;
      }
      break;

    default:
      cur_arg->X_op = crx_ins->exp.X_op;
      break;
    }

  input_line_pointer = saved_input_line_pointer;
  return;
}

/* Get the values of the scale to be encoded -
   used for the scaled index mode of addressing.  */

static int
exponent2scale (int val)
{
  int exponent;

  /* If 'val' is 0, the following 'for' will be an endless loop.  */
  if (val == 0)
    return 0;

  for (exponent = 0; (val != 1); val >>= 1, exponent++)
    ;

  return exponent;
}

/* Parsing different types of operands
   -> constants		    Immediate/Absolute/Relative numbers
   -> Labels		    Relocatable symbols
   -> (rbase)		    Register base
   -> disp(rbase)	    Register relative
   -> disp(rbase)+	    Post-increment mode
   -> disp(rbase,ridx,scl)  Register index mode  */

static void
set_operand (char *operand, ins * crx_ins)
{
  char *operandS; /* Pointer to start of sub-operand.  */
  char *operandE; /* Pointer to end of sub-operand.  */
  expressionS scale;
  int scale_val;
  char *input_save, c;
  argument *cur_arg = &crx_ins->arg[cur_arg_num]; /* Current argument.  */

  /* Initialize pointers.  */
  operandS = operandE = operand;

  switch (cur_arg->type)
    {
    case arg_sc:    /* Case *+0x18.  */
    case arg_ic:    /* Case $0x18.  */
      operandS++;
      /* Fall through.  */
    case arg_c:	    /* Case 0x18.  */
      /* Set constant.  */
      process_label_constant (operandS, crx_ins);

      if (cur_arg->type != arg_ic)
	cur_arg->type = arg_c;
      break;

    case arg_icr:   /* Case $0x18(r1).  */
      operandS++;
    case arg_cr:    /* Case 0x18(r1).   */
      /* Set displacement constant.  */
      while (*operandE != '(')
	operandE++;
      *operandE = '\0';
      process_label_constant (operandS, crx_ins);
      operandS = operandE;
      /* Fall through.  */
    case arg_rbase: /* Case (r1).  */
      operandS++;
      /* Set register base.  */
      while (*operandE != ')')
	operandE++;
      *operandE = '\0';
      if ((cur_arg->r = get_register (operandS)) == nullregister)
	as_bad (_("Illegal register `%s' in instruction `%s'"),
		operandS, ins_parse);

      if (cur_arg->type != arg_rbase)
	cur_arg->type = arg_cr;
      break;

    case arg_idxr:
      /* Set displacement constant.  */
      while (*operandE != '(')
	operandE++;
      *operandE = '\0';
      process_label_constant (operandS, crx_ins);
      operandS = ++operandE;

      /* Set register base.  */
      while ((*operandE != ',') && (! ISSPACE (*operandE)))
	operandE++;
      *operandE++ = '\0';
      if ((cur_arg->r = get_register (operandS)) == nullregister)
	as_bad (_("Illegal register `%s' in instruction `%s'"),
		operandS, ins_parse);

      /* Skip leading white space.  */
      while (ISSPACE (*operandE))
	operandE++;
      operandS = operandE;

      /* Set register index.  */
      while ((*operandE != ')') && (*operandE != ','))
	operandE++;
      c = *operandE;
      *operandE++ = '\0';

      if ((cur_arg->i_r = get_register (operandS)) == nullregister)
	as_bad (_("Illegal register `%s' in instruction `%s'"),
		operandS, ins_parse);

      /* Skip leading white space.  */
      while (ISSPACE (*operandE))
	operandE++;
      operandS = operandE;

      /* Set the scale.  */
      if (c == ')')
	cur_arg->scale = 0;
      else
        {
	  while (*operandE != ')')
	    operandE++;
	  *operandE = '\0';

	  /* Preprocess the scale string.  */
	  input_save = input_line_pointer;
	  input_line_pointer = operandS;
	  expression (&scale);
	  input_line_pointer = input_save;

	  scale_val = scale.X_add_number;

	  /* Check if the scale value is legal.  */
          if (scale_val != 1 && scale_val != 2
              && scale_val != 4 && scale_val != 8)
	    as_bad (_("Illegal Scale - `%d'"), scale_val);

	  cur_arg->scale = exponent2scale (scale_val);
        }
      break;

    default:
      break;
    }
}

/* Parse a single operand.
   operand - Current operand to parse.
   crx_ins - Current assembled instruction.  */

static void
parse_operand (char *operand, ins * crx_ins)
{
  int ret_val;
  argument *cur_arg = &crx_ins->arg[cur_arg_num]; /* Current argument.  */

  /* Initialize the type to NULL before parsing.  */
  cur_arg->type = nullargs;

  /* Check whether this is a general processor register.  */
  if ((ret_val = get_register (operand)) != nullregister)
    {
      cur_arg->type = arg_r;
      cur_arg->r = ret_val;
      cur_arg->X_op = O_register;
      return;
    }

  /* Check whether this is a core [special] coprocessor register.  */
  if ((ret_val = get_copregister (operand)) != nullcopregister)
    {
      cur_arg->type = arg_copr;
      if (ret_val >= cs0)
	cur_arg->type = arg_copsr;
      cur_arg->cr = ret_val;
      cur_arg->X_op = O_register;
      return;
    }

  /* Deal with special characters.  */
  switch (operand[0])
    {
    case '$':
      if (strchr (operand, '(') != NULL)
	cur_arg->type = arg_icr;
      else
        cur_arg->type = arg_ic;
      goto set_params;
      break;

    case '*':
      cur_arg->type = arg_sc;
      goto set_params;
      break;

    case '(':
      cur_arg->type = arg_rbase;
      goto set_params;
      break;

    default:
	break;
    }

  if (strchr (operand, '(') != NULL)
    {
      if (strchr (operand, ',') != NULL
          && (strchr (operand, ',') > strchr (operand, '(')))
	    cur_arg->type = arg_idxr;
      else
	cur_arg->type = arg_cr;
    }
  else
    cur_arg->type = arg_c;
  goto set_params;

/* Parse an operand according to its type.  */
set_params:
  cur_arg->constant = 0;
  set_operand (operand, crx_ins);
}

/* Parse the various operands. Each operand is then analyzed to fillup
   the fields in the crx_ins data structure.  */

static void
parse_operands (ins * crx_ins, char *operands)
{
  char *operandS;	       /* Operands string.  */
  char *operandH, *operandT;   /* Single operand head/tail pointers.  */
  int allocated = 0;	       /* Indicates a new operands string was allocated.  */
  char *operand[MAX_OPERANDS]; /* Separating the operands.  */
  int op_num = 0;	       /* Current operand number we are parsing.  */
  int bracket_flag = 0;	       /* Indicates a bracket '(' was found.  */
  int sq_bracket_flag = 0;     /* Indicates a square bracket '[' was found.  */

  /* Preprocess the list of registers, if necessary.  */
  operandS = operandH = operandT = (INST_HAS_REG_LIST) ?
    preprocess_reglist (operands, &allocated) : operands;

  while (*operandT != '\0')
    {
      if (*operandT == ',' && bracket_flag != 1 && sq_bracket_flag != 1)
        {
	  *operandT++ = '\0';
	  operand[op_num++] = strdup (operandH);
          operandH = operandT;
          continue;
        }

      if (*operandT == ' ')
	as_bad (_("Illegal operands (whitespace): `%s'"), ins_parse);

      if (*operandT == '(')
	bracket_flag = 1;
      else if (*operandT == '[')
	sq_bracket_flag = 1;

      if (*operandT == ')')
	{
	  if (bracket_flag)
	    bracket_flag = 0;
	  else
	    as_fatal (_("Missing matching brackets : `%s'"), ins_parse);
	}
      else if (*operandT == ']')
	{
	  if (sq_bracket_flag)
	    sq_bracket_flag = 0;
	  else
	    as_fatal (_("Missing matching brackets : `%s'"), ins_parse);
	}

      if (bracket_flag == 1 && *operandT == ')')
	bracket_flag = 0;
      else if (sq_bracket_flag == 1 && *operandT == ']')
	sq_bracket_flag = 0;

      operandT++;
    }

  /* Adding the last operand.  */
  operand[op_num++] = strdup (operandH);
  crx_ins->nargs = op_num;

  /* Verifying correct syntax of operands (all brackets should be closed).  */
  if (bracket_flag || sq_bracket_flag)
    as_fatal (_("Missing matching brackets : `%s'"), ins_parse);

  /* Now we parse each operand separately.  */
  for (op_num = 0; op_num < crx_ins->nargs; op_num++)
    {
      cur_arg_num = op_num;
      parse_operand (operand[op_num], crx_ins);
      free (operand[op_num]);
    }

  if (allocated)
    free (operandS);
}

/* Get the trap index in dispatch table, given its name.
   This routine is used by assembling the 'excp' instruction.  */

static int
gettrap (const char *s)
{
  const trap_entry *trap;

  for (trap = crx_traps; trap < (crx_traps + NUMTRAPS); trap++)
    if (strcasecmp (trap->name, s) == 0)
      return trap->entry;

  as_bad (_("Unknown exception: `%s'"), s);
  return 0;
}

/* Post-Increment instructions, as well as Store-Immediate instructions, are a
   sub-group within load/stor instruction groups.
   Therefore, when parsing a Post-Increment/Store-Immediate insn, we have to
   advance the instruction pointer to the start of that sub-group (that is, up
   to the first instruction of that type).
   Otherwise, the insn will be mistakenly identified as of type LD_STOR_INS.  */

static void
handle_LoadStor (const char *operands)
{
  /* Post-Increment instructions precede Store-Immediate instructions in
     CRX instruction table, hence they are handled before.
     This synchronization should be kept.  */

  /* Assuming Post-Increment insn has the following format :
     'MNEMONIC DISP(REG)+, REG' (e.g. 'loadw 12(r5)+, r6').
     LD_STOR_INS_INC are the only store insns containing a plus sign (+).  */
  if (strstr (operands, ")+") != NULL)
    {
      while (! IS_INSN_TYPE (LD_STOR_INS_INC))
	instruction++;
      return;
    }

  /* Assuming Store-Immediate insn has the following format :
     'MNEMONIC $DISP, ...' (e.g. 'storb $1, 12(r5)').
     STOR_IMM_INS are the only store insns containing a dollar sign ($).  */
  if (strstr (operands, "$") != NULL)
    while (! IS_INSN_TYPE (STOR_IMM_INS))
      instruction++;
}

/* Top level module where instruction parsing starts.
   crx_ins - data structure holds some information.
   operands - holds the operands part of the whole instruction.  */

static void
parse_insn (ins *insn, char *operands)
{
  int i;

  /* Handle instructions with no operands.  */
  for (i = 0; crx_no_op_insn[i] != NULL; i++)
  {
    if (streq (crx_no_op_insn[i], instruction->mnemonic))
    {
      insn->nargs = 0;
      return;
    }
  }

  /* Handle 'excp'/'cinv' instructions.  */
  if (IS_INSN_MNEMONIC ("excp") || IS_INSN_MNEMONIC ("cinv"))
    {
      insn->nargs = 1;
      insn->arg[0].type = arg_ic;
      insn->arg[0].constant = IS_INSN_MNEMONIC ("excp") ?
	gettrap (operands) : get_cinv_parameters (operands);
      insn->arg[0].X_op = O_constant;
      return;
    }

  /* Handle load/stor unique instructions before parsing.  */
  if (IS_INSN_TYPE (LD_STOR_INS))
    handle_LoadStor (operands);

  if (operands != NULL)
    parse_operands (insn, operands);
}

/* Cinv instruction requires special handling.  */

static int
get_cinv_parameters (const char *operand)
{
  const char *p = operand;
  int d_used = 0, i_used = 0, u_used = 0, b_used = 0;

  while (*++p != ']')
    {
      if (*p == ',' || *p == ' ')
	continue;

      if (*p == 'd')
	d_used = 1;
      else if (*p == 'i')
	i_used = 1;
      else if (*p == 'u')
	u_used = 1;
      else if (*p == 'b')
	b_used = 1;
      else
	as_bad (_("Illegal `cinv' parameter: `%c'"), *p);
    }

  return ((b_used ? 8 : 0)
	+ (d_used ? 4 : 0)
	+ (i_used ? 2 : 0)
	+ (u_used ? 1 : 0));
}

/* Retrieve the opcode image of a given register.
   If the register is illegal for the current instruction,
   issue an error.  */

static int
getreg_image (reg r)
{
  const reg_entry *rreg;
  char *reg_name;
  int is_procreg = 0; /* Nonzero means argument should be processor reg.  */

  if (((IS_INSN_MNEMONIC ("mtpr")) && (cur_arg_num == 1))
      || ((IS_INSN_MNEMONIC ("mfpr")) && (cur_arg_num == 0)) )
    is_procreg = 1;

  /* Check whether the register is in registers table.  */
  if (r < MAX_REG)
    rreg = &crx_regtab[r];
  /* Check whether the register is in coprocessor registers table.  */
  else if (r < (int) MAX_COPREG)
    rreg = &crx_copregtab[r-MAX_REG];
  /* Register not found.  */
  else
    {
      as_bad (_("Unknown register: `%d'"), r);
      return 0;
    }

  reg_name = rreg->name;

/* Issue a error message when register is illegal.  */
#define IMAGE_ERR \
  as_bad (_("Illegal register (`%s') in instruction: `%s'"), \
	  reg_name, ins_parse);

  switch (rreg->type)
  {
    case CRX_U_REGTYPE:
      if (is_procreg || (instruction->flags & USER_REG))
	return rreg->image;
      else
	IMAGE_ERR;
      break;

    case CRX_CFG_REGTYPE:
      if (is_procreg)
	return rreg->image;
      else
	IMAGE_ERR;
      break;

    case CRX_R_REGTYPE:
      if (! is_procreg)
	return rreg->image;
      else
	IMAGE_ERR;
      break;

    case CRX_C_REGTYPE:
    case CRX_CS_REGTYPE:
      return rreg->image;
      break;

    default:
      IMAGE_ERR;
      break;
  }

  return 0;
}

/* Routine used to represent integer X using NBITS bits.  */

static long
getconstant (long x, int nbits)
{
  return x & ((((1U << (nbits - 1)) - 1) << 1) | 1);
}

/* Print a constant value to 'output_opcode':
   ARG holds the operand's type and value.
   SHIFT represents the location of the operand to be print into.
   NBITS determines the size (in bits) of the constant.  */

static void
print_constant (int nbits, int shift, argument *arg)
{
  unsigned long mask = 0;

  long constant = getconstant (arg->constant, nbits);

  switch (nbits)
  {
    case 32:
    case 28:
    case 24:
    case 22:
      /* mask the upper part of the constant, that is, the bits
	 going to the lowest byte of output_opcode[0].
	 The upper part of output_opcode[1] is always filled,
	 therefore it is always masked with 0xFFFF.  */
      mask = (1 << (nbits - 16)) - 1;
      /* Divide the constant between two consecutive words :
		 0	   1	     2	       3
	    +---------+---------+---------+---------+
	    |	      | X X X X | X X X X |	    |
	    +---------+---------+---------+---------+
	      output_opcode[0]    output_opcode[1]     */

      CRX_PRINT (0, (constant >> WORD_SHIFT) & mask, 0);
      CRX_PRINT (1, (constant & 0xFFFF), WORD_SHIFT);
      break;

    case 16:
    case 12:
      /* Special case - in arg_cr, the SHIFT represents the location
	 of the REGISTER, not the constant, which is itself not shifted.  */
      if (arg->type == arg_cr)
	{
	  CRX_PRINT (0, constant,  0);
	  break;
	}

      /* When instruction size is 3 and 'shift' is 16, a 16-bit constant is
	 always filling the upper part of output_opcode[1]. If we mistakenly
	 write it to output_opcode[0], the constant prefix (that is, 'match')
	 will be overridden.
		 0	   1	     2	       3
	    +---------+---------+---------+---------+
	    | 'match' |         | X X X X |	    |
	    +---------+---------+---------+---------+
	      output_opcode[0]    output_opcode[1]     */

      if ((instruction->size > 2) && (shift == WORD_SHIFT))
	CRX_PRINT (1, constant, WORD_SHIFT);
      else
	CRX_PRINT (0, constant, shift);
      break;

    default:
      CRX_PRINT (0, constant,  shift);
      break;
  }
}

/* Print an operand to 'output_opcode', which later on will be
   printed to the object file:
   ARG holds the operand's type, size and value.
   SHIFT represents the printing location of operand.
   NBITS determines the size (in bits) of a constant operand.  */

static void
print_operand (int nbits, int shift, argument *arg)
{
  switch (arg->type)
    {
    case arg_r:
      CRX_PRINT (0, getreg_image (arg->r), shift);
      break;

    case arg_copr:
      if (arg->cr < c0 || arg->cr > c15)
	as_bad (_("Illegal co-processor register in instruction `%s'"),
		ins_parse);
      CRX_PRINT (0, getreg_image (arg->cr), shift);
      break;

    case arg_copsr:
      if (arg->cr < cs0 || arg->cr > cs15)
	as_bad (_("Illegal co-processor special register in instruction `%s'"),
		ins_parse);
      CRX_PRINT (0, getreg_image (arg->cr), shift);
      break;

    case arg_idxr:
      /*    16      12	      8    6         0
	    +--------------------------------+
	    | r_base | r_idx  | scl|  disp   |
	    +--------------------------------+	  */
      CRX_PRINT (0, getreg_image (arg->r), 12);
      CRX_PRINT (0, getreg_image (arg->i_r), 8);
      CRX_PRINT (0, arg->scale, 6);
      /* Fall through.  */
    case arg_ic:
    case arg_c:
      print_constant (nbits, shift, arg);
      break;

    case arg_rbase:
      CRX_PRINT (0, getreg_image (arg->r), shift);
      break;

    case arg_cr:
      /* case base_cst4.  */
      if (instruction->flags & DISPU4MAP)
	print_constant (nbits, shift + REG_SIZE, arg);
      else
	/* rbase_disps<NN> and other such cases.  */
	print_constant (nbits, shift, arg);
      /* Add the register argument to the output_opcode.  */
      CRX_PRINT (0, getreg_image (arg->r), shift);
      break;

    default:
      break;
    }
}

/* Retrieve the number of operands for the current assembled instruction.  */

static int
get_number_of_operands (void)
{
  int i;

  for (i = 0; instruction->operands[i].op_type && i < MAX_OPERANDS; i++)
    ;
  return i;
}

/* Verify that the number NUM can be represented in BITS bits (that is,
   within its permitted range), based on the instruction's FLAGS.
   If UPDATE is nonzero, update the value of NUM if necessary.
   Return OP_LEGAL upon success, actual error type upon failure.  */

static op_err
check_range (long *num, int bits, int unsigned flags, int update)
{
  uint32_t max;
  op_err retval = OP_LEGAL;
  int bin;
  uint32_t upper_64kb = 0xffff0000;
  uint32_t value = *num;

  /* Verify operand value is even.  */
  if (flags & OP_EVEN)
    {
      if (value % 2)
	return OP_NOT_EVEN;
    }

  if (flags & OP_UPPER_64KB)
    {
      /* Check if value is to be mapped to upper 64 KB memory area.  */
      if ((value & upper_64kb) == upper_64kb)
	{
	  value -= upper_64kb;
	  if (update)
	    *num = value;
	}
      else
	return OP_NOT_UPPER_64KB;
    }

  if (flags & OP_SHIFT)
    {
      /* All OP_SHIFT args are also OP_SIGNED, so we want to keep the
	 sign.  However, right shift of a signed type with a negative
	 value is implementation defined.  See ISO C 6.5.7.  So we use
	 an unsigned type and sign extend afterwards.  */
      value >>= 1;
      value = (value ^ 0x40000000) - 0x40000000;
      if (update)
	*num = value;
    }
  else if (flags & OP_SHIFT_DEC)
    {
      value = (value >> 1) - 1;
      if (update)
	*num = value;
    }

  if (flags & OP_ESC)
    {
      /* 0x7e and 0x7f are reserved escape sequences of dispe9.  */
      if (value == 0x7e || value == 0x7f)
	return OP_OUT_OF_RANGE;
    }

  if (flags & OP_DISPU4)
    {
      int is_dispu4 = 0;

      uint32_t mul = (instruction->flags & DISPUB4 ? 1
		      : instruction->flags & DISPUW4 ? 2
		      : instruction->flags & DISPUD4 ? 4
		      : 0);

      for (bin = 0; bin < crx_cst4_maps; bin++)
	{
	  if (value == mul * bin)
	    {
	      is_dispu4 = 1;
	      if (update)
		*num = bin;
	      break;
	    }
	}
      if (!is_dispu4)
	retval = OP_ILLEGAL_DISPU4;
    }
  else if (flags & OP_CST4)
    {
      int is_cst4 = 0;

      for (bin = 0; bin < crx_cst4_maps; bin++)
	{
	  if (value == (uint32_t) crx_cst4_map[bin])
	    {
	      is_cst4 = 1;
	      if (update)
		*num = bin;
	      break;
	    }
	}
      if (!is_cst4)
	retval = OP_ILLEGAL_CST4;
    }
  else if (flags & OP_SIGNED)
    {
      max = 1;
      max = max << (bits - 1);
      value += max;
      max = ((max - 1) << 1) | 1;
      if (value > max)
	retval = OP_OUT_OF_RANGE;
    }
  else if (flags & OP_UNSIGNED)
    {
      max = 1;
      max = max << (bits - 1);
      max = ((max - 1) << 1) | 1;
      if (value > max)
	retval = OP_OUT_OF_RANGE;
    }
  return retval;
}

/* Assemble a single instruction:
   INSN is already parsed (that is, all operand values and types are set).
   For instruction to be assembled, we need to find an appropriate template in
   the instruction table, meeting the following conditions:
    1: Has the same number of operands.
    2: Has the same operand types.
    3: Each operand size is sufficient to represent the instruction's values.
   Returns 1 upon success, 0 upon failure.  */

static int
assemble_insn (char *mnemonic, ins *insn)
{
  /* Type of each operand in the current template.  */
  argtype cur_type[MAX_OPERANDS];
  /* Size (in bits) of each operand in the current template.  */
  unsigned int cur_size[MAX_OPERANDS];
  /* Flags of each operand in the current template.  */
  unsigned int cur_flags[MAX_OPERANDS];
  /* Instruction type to match.  */
  unsigned int ins_type;
  /* Boolean flag to mark whether a match was found.  */
  int match = 0;
  int i;
  /* Nonzero if an instruction with same number of operands was found.  */
  int found_same_number_of_operands = 0;
  /* Nonzero if an instruction with same argument types was found.  */
  int found_same_argument_types = 0;
  /* Nonzero if a constant was found within the required range.  */
  int found_const_within_range  = 0;
  /* Argument number of an operand with invalid type.  */
  int invalid_optype = -1;
  /* Argument number of an operand with invalid constant value.  */
  int invalid_const  = -1;
  /* Operand error (used for issuing various constant error messages).  */
  op_err op_error, const_err = OP_LEGAL;

/* Retrieve data (based on FUNC) for each operand of a given instruction.  */
#define GET_CURRENT_DATA(FUNC, ARRAY)				  \
  for (i = 0; i < insn->nargs; i++)				  \
    ARRAY[i] = FUNC (instruction->operands[i].op_type)

#define GET_CURRENT_TYPE    GET_CURRENT_DATA(get_optype, cur_type)
#define GET_CURRENT_SIZE    GET_CURRENT_DATA(get_opbits, cur_size)
#define GET_CURRENT_FLAGS   GET_CURRENT_DATA(get_opflags, cur_flags)

  /* Instruction has no operands -> only copy the constant opcode.   */
  if (insn->nargs == 0)
    {
      output_opcode[0] = BIN (instruction->match, instruction->match_bits);
      return 1;
    }

  /* In some case, same mnemonic can appear with different instruction types.
     For example, 'storb' is supported with 3 different types :
     LD_STOR_INS, LD_STOR_INS_INC, STOR_IMM_INS.
     We assume that when reaching this point, the instruction type was
     pre-determined. We need to make sure that the type stays the same
     during a search for matching instruction.  */
  ins_type = CRX_INS_TYPE(instruction->flags);

  while (/* Check that match is still not found.  */
	 match != 1
	 /* Check we didn't get to end of table.  */
	 && instruction->mnemonic != NULL
	 /* Check that the actual mnemonic is still available.  */
	 && IS_INSN_MNEMONIC (mnemonic)
	 /* Check that the instruction type wasn't changed.  */
	 && IS_INSN_TYPE(ins_type))
    {
      /* Check whether number of arguments is legal.  */
      if (get_number_of_operands () != insn->nargs)
	goto next_insn;
      found_same_number_of_operands = 1;

      /* Initialize arrays with data of each operand in current template.  */
      GET_CURRENT_TYPE;
      GET_CURRENT_SIZE;
      GET_CURRENT_FLAGS;

      /* Check for type compatibility.  */
      for (i = 0; i < insn->nargs; i++)
        {
	  if (cur_type[i] != insn->arg[i].type)
	    {
	      if (invalid_optype == -1)
		invalid_optype = i + 1;
	      goto next_insn;
	    }
	}
      found_same_argument_types = 1;

      for (i = 0; i < insn->nargs; i++)
	{
	  /* Reverse the operand indices for certain opcodes:
	     Index 0	  -->> 1
	     Index 1	  -->> 0
	     Other index  -->> stays the same.  */
	  int j = instruction->flags & REVERSE_MATCH ?
		  i == 0 ? 1 :
		  i == 1 ? 0 : i :
		  i;

	  /* Only check range - don't update the constant's value, since the
	     current instruction may not be the last we try to match.
	     The constant's value will be updated later, right before printing
	     it to the object file.  */
  	  if ((insn->arg[j].X_op == O_constant)
	       && (op_error = check_range (&insn->arg[j].constant, cur_size[j],
					   cur_flags[j], 0)))
  	    {
	      if (invalid_const == -1)
	      {
		invalid_const = j + 1;
		const_err = op_error;
	      }
	      goto next_insn;
	    }
	  /* For symbols, we make sure the relocation size (which was already
	     determined) is sufficient.  */
	  else if ((insn->arg[j].X_op == O_symbol)
		    && ((bfd_reloc_type_lookup (stdoutput, insn->rtype))->bitsize
			 > cur_size[j]))
		  goto next_insn;
	}
      found_const_within_range = 1;

      /* If we got till here -> Full match is found.  */
      match = 1;
      break;

/* Try again with next instruction.  */
next_insn:
      instruction++;
    }

  if (!match)
    {
      /* We haven't found a match - instruction can't be assembled.  */
      if (!found_same_number_of_operands)
	as_bad (_("Incorrect number of operands"));
      else if (!found_same_argument_types)
	as_bad (_("Illegal type of operand (arg %d)"), invalid_optype);
      else if (!found_const_within_range)
      {
	switch (const_err)
	{
	case OP_OUT_OF_RANGE:
	  as_bad (_("Operand out of range (arg %d)"), invalid_const);
	  break;
	case OP_NOT_EVEN:
	  as_bad (_("Operand has odd displacement (arg %d)"), invalid_const);
	  break;
	case OP_ILLEGAL_DISPU4:
	  as_bad (_("Invalid DISPU4 operand value (arg %d)"), invalid_const);
	  break;
	case OP_ILLEGAL_CST4:
	  as_bad (_("Invalid CST4 operand value (arg %d)"), invalid_const);
	  break;
	case OP_NOT_UPPER_64KB:
	  as_bad (_("Operand value is not within upper 64 KB (arg %d)"),
		    invalid_const);
	  break;
	default:
	  as_bad (_("Illegal operand (arg %d)"), invalid_const);
	  break;
	}
      }

      return 0;
    }
  else
    /* Full match - print the encoding to output file.  */
    {
      /* Make further checking (such that couldn't be made earlier).
	 Warn the user if necessary.  */
      warn_if_needed (insn);

      /* Check whether we need to adjust the instruction pointer.  */
      if (adjust_if_needed (insn))
	/* If instruction pointer was adjusted, we need to update
	   the size of the current template operands.  */
	GET_CURRENT_SIZE;

      for (i = 0; i < insn->nargs; i++)
        {
	  int j = instruction->flags & REVERSE_MATCH ?
		  i == 0 ? 1 :
		  i == 1 ? 0 : i :
		  i;

	  /* This time, update constant value before printing it.  */
  	  if ((insn->arg[j].X_op == O_constant)
	       && (check_range (&insn->arg[j].constant, cur_size[j],
				cur_flags[j], 1) != OP_LEGAL))
	      as_fatal (_("Illegal operand (arg %d)"), j+1);
	}

      /* First, copy the instruction's opcode.  */
      output_opcode[0] = BIN (instruction->match, instruction->match_bits);

      for (i = 0; i < insn->nargs; i++)
        {
	  cur_arg_num = i;
          print_operand (cur_size[i], instruction->operands[i].shift,
			 &insn->arg[i]);
        }
    }

  return 1;
}

/* Bunch of error checking.
   The checks are made after a matching instruction was found.  */

void
warn_if_needed (ins *insn)
{
  /* If the post-increment address mode is used and the load/store
     source register is the same as rbase, the result of the
     instruction is undefined.  */
  if (IS_INSN_TYPE (LD_STOR_INS_INC))
    {
      /* Enough to verify that one of the arguments is a simple reg.  */
      if ((insn->arg[0].type == arg_r) || (insn->arg[1].type == arg_r))
	if (insn->arg[0].r == insn->arg[1].r)
	  as_bad (_("Same src/dest register is used (`r%d'), result is undefined"),
		   insn->arg[0].r);
    }

  /* Some instruction assume the stack pointer as rptr operand.
     Issue an error when the register to be loaded is also SP.  */
  if (instruction->flags & NO_SP)
    {
      if (getreg_image (insn->arg[0].r) == getreg_image (sp))
	as_bad (_("`%s' has undefined result"), ins_parse);
    }

  /* If the rptr register is specified as one of the registers to be loaded,
     the final contents of rptr are undefined. Thus, we issue an error.  */
  if (instruction->flags & NO_RPTR)
    {
      if ((1 << getreg_image (insn->arg[0].r)) & insn->arg[1].constant)
	as_bad (_("Same src/dest register is used (`r%d'), result is undefined"),
	 getreg_image (insn->arg[0].r));
    }
}

/* In some cases, we need to adjust the instruction pointer although a
   match was already found. Here, we gather all these cases.
   Returns 1 if instruction pointer was adjusted, otherwise 0.  */

int
adjust_if_needed (ins *insn)
{
  int ret_value = 0;

  /* Special check for 'addub $0, r0' instruction -
     The opcode '0000 0000 0000 0000' is not allowed.  */
  if (IS_INSN_MNEMONIC ("addub"))
    {
      if ((instruction->operands[0].op_type == cst4)
	  && instruction->operands[1].op_type == regr)
        {
          if (insn->arg[0].constant == 0 && insn->arg[1].r == r0)
	    {
	      instruction++;
	      ret_value = 1;
	    }
        }
    }

  /* Optimization: Omit a zero displacement in bit operations,
     saving 2-byte encoding space (e.g., 'cbitw $8, 0(r1)').  */
  if (IS_INSN_TYPE (CSTBIT_INS))
    {
      if ((instruction->operands[1].op_type == rbase_disps12)
	   && (insn->arg[1].X_op == O_constant)
	   && (insn->arg[1].constant == 0))
            {
              instruction--;
	      ret_value = 1;
            }
    }

  return ret_value;
}

/* Set the appropriate bit for register 'r' in 'mask'.
   This indicates that this register is loaded or stored by
   the instruction.  */

static void
mask_reg (int r, unsigned short int *mask)
{
  if ((reg)r > (reg)sp)
    {
      as_bad (_("Invalid register in register list"));
      return;
    }

  *mask |= (1 << r);
}

/* Preprocess register list - create a 16-bit mask with one bit for each
   of the 16 general purpose registers. If a bit is set, it indicates
   that this register is loaded or stored by the instruction.  */

static char *
preprocess_reglist (char *param, int *allocated)
{
  char reg_name[MAX_REGNAME_LEN]; /* Current parsed register name.  */
  char *regP;			  /* Pointer to 'reg_name' string.  */
  int reg_counter = 0;		  /* Count number of parsed registers.  */
  unsigned short int mask = 0;	  /* Mask for 16 general purpose registers.  */
  char *new_param;		  /* New created operands string.  */
  char *paramP = param;		  /* Pointer to original operands string.  */
  char maskstring[10];		  /* Array to print the mask as a string.  */
  int hi_found = 0, lo_found = 0; /* Boolean flags for hi/lo registers.  */
  reg r;
  copreg cr;

  /* If 'param' is already in form of a number, no need to preprocess.  */
  if (strchr (paramP, '{') == NULL)
    return param;

  /* Verifying correct syntax of operand.  */
  if (strchr (paramP, '}') == NULL)
    as_fatal (_("Missing matching brackets : `%s'"), ins_parse);

  while (*paramP++ != '{');

  new_param = XCNEWVEC (char, MAX_INST_LEN);
  *allocated = 1;
  strncpy (new_param, param, paramP - param - 1);

  while (*paramP != '}')
    {
      regP = paramP;
      memset (&reg_name, '\0', sizeof (reg_name));

      while (ISALNUM (*paramP))
	paramP++;

      strncpy (reg_name, regP, paramP - regP);

      /* Coprocessor register c<N>.  */
      if (IS_INSN_TYPE (COP_REG_INS))
        {
          if (((cr = get_copregister (reg_name)) == nullcopregister)
	      || (crx_copregtab[cr-MAX_REG].type != CRX_C_REGTYPE))
	    as_fatal (_("Illegal register `%s' in cop-register list"), reg_name);
	  mask_reg (getreg_image (cr - c0), &mask);
        }
      /* Coprocessor Special register cs<N>.  */
      else if (IS_INSN_TYPE (COPS_REG_INS))
        {
          if (((cr = get_copregister (reg_name)) == nullcopregister)
	      || (crx_copregtab[cr-MAX_REG].type != CRX_CS_REGTYPE))
	    as_fatal (_("Illegal register `%s' in cop-special-register list"),
		      reg_name);
	  mask_reg (getreg_image (cr - cs0), &mask);
        }
      /* User register u<N>.  */
      else if (instruction->flags & USER_REG)
	{
	  if (streq(reg_name, "uhi"))
	    {
	      hi_found = 1;
	      goto next_inst;
	    }
	  else if (streq(reg_name, "ulo"))
	    {
	      lo_found = 1;
	      goto next_inst;
	    }
          else if (((r = get_register (reg_name)) == nullregister)
	      || (crx_regtab[r].type != CRX_U_REGTYPE))
	    as_fatal (_("Illegal register `%s' in user register list"), reg_name);

	  mask_reg (getreg_image (r - u0), &mask);
	}
      /* General purpose register r<N>.  */
      else
        {
	  if (streq(reg_name, "hi"))
	    {
	      hi_found = 1;
	      goto next_inst;
	    }
	  else if (streq(reg_name, "lo"))
	    {
	      lo_found = 1;
	      goto next_inst;
	    }
          else if (((r = get_register (reg_name)) == nullregister)
	      || (crx_regtab[r].type != CRX_R_REGTYPE))
	    as_fatal (_("Illegal register `%s' in register list"), reg_name);

	  mask_reg (getreg_image (r - r0), &mask);
        }

      if (++reg_counter > MAX_REGS_IN_MASK16)
	as_bad (_("Maximum %d bits may be set in `mask16' operand"),
		MAX_REGS_IN_MASK16);

next_inst:
      while (!ISALNUM (*paramP) && *paramP != '}')
	  paramP++;
    }

  if (*++paramP != '\0')
    as_warn (_("rest of line ignored; first ignored character is `%c'"),
	     *paramP);

  switch (hi_found + lo_found)
    {
    case 0:
      /* At least one register should be specified.  */
      if (mask == 0)
	as_bad (_("Illegal `mask16' operand, operation is undefined - `%s'"),
		ins_parse);
      break;

    case 1:
      /* HI can't be specified without LO (and vise-versa).  */
      as_bad (_("HI/LO registers should be specified together"));
      break;

    case 2:
      /* HI/LO registers mustn't be masked with additional registers.  */
      if (mask != 0)
	as_bad (_("HI/LO registers should be specified without additional registers"));

    default:
      break;
    }

  sprintf (maskstring, "$0x%x", mask);
  strcat (new_param, maskstring);
  return new_param;
}

/* Print the instruction.
   Handle also cases where the instruction is relaxable/relocatable.  */

void
print_insn (ins *insn)
{
  unsigned int i, j, insn_size;
  char *this_frag;
  unsigned short words[4];
  int addr_mod;

  /* Arrange the insn encodings in a WORD size array.  */
  for (i = 0, j = 0; i < 2; i++)
    {
      words[j++] = (output_opcode[i] >> 16) & 0xFFFF;
      words[j++] = output_opcode[i] & 0xFFFF;
    }

  /* Handle relaxation.  */
  if ((instruction->flags & RELAXABLE) && relocatable)
    {
      int relax_subtype;

      /* Write the maximal instruction size supported.  */
      insn_size = INSN_MAX_SIZE;

      /* bCC  */
      if (IS_INSN_TYPE (BRANCH_INS))
	relax_subtype = 0;
      /* bal  */
      else if (IS_INSN_TYPE (DCR_BRANCH_INS) || IS_INSN_MNEMONIC ("bal"))
	relax_subtype = 3;
      /* cmpbr/bcop  */
      else if (IS_INSN_TYPE (CMPBR_INS) || IS_INSN_TYPE (COP_BRANCH_INS))
	relax_subtype = 5;
      else
	abort ();

      this_frag = frag_var (rs_machine_dependent, insn_size * 2,
			    4, relax_subtype,
			    insn->exp.X_add_symbol,
			    insn->exp.X_add_number,
			    0);
    }
  else
    {
      insn_size = instruction->size;
      this_frag = frag_more (insn_size * 2);

      /* Handle relocation.  */
      if ((relocatable) && (insn->rtype != BFD_RELOC_NONE))
	{
	  reloc_howto_type *reloc_howto;
	  int size;

	  reloc_howto = bfd_reloc_type_lookup (stdoutput, insn->rtype);

	  if (!reloc_howto)
	    abort ();

	  size = bfd_get_reloc_size (reloc_howto);

	  if (size < 1 || size > 4)
	    abort ();

	  fix_new_exp (frag_now, this_frag - frag_now->fr_literal,
		       size, &insn->exp, reloc_howto->pc_relative,
		       insn->rtype);
	}
    }

  /* Verify a 2-byte code alignment.  */
  addr_mod = frag_now_fix () & 1;
  if (frag_now->has_code && frag_now->insn_addr != addr_mod)
    as_bad (_("instruction address is not a multiple of 2"));
  frag_now->insn_addr = addr_mod;
  frag_now->has_code = 1;

  /* Write the instruction encoding to frag.  */
  for (i = 0; i < insn_size; i++)
    {
      md_number_to_chars (this_frag, (valueT) words[i], 2);
      this_frag += 2;
    }
}

/* This is the guts of the machine-dependent assembler.  OP points to a
   machine dependent instruction.  This function is supposed to emit
   the frags/bytes it assembles to.  */

void
md_assemble (char *op)
{
  ins crx_ins;
  char *param;
  char c;

  /* Reset global variables for a new instruction.  */
  reset_vars (op);

  /* Strip the mnemonic.  */
  for (param = op; *param != 0 && !ISSPACE (*param); param++)
    ;
  c = *param;
  *param++ = '\0';

  /* Find the instruction.  */
  instruction = (const inst *) hash_find (crx_inst_hash, op);
  if (instruction == NULL)
    {
      as_bad (_("Unknown opcode: `%s'"), op);
      param[-1] = c;
      return;
    }

  /* Tie dwarf2 debug info to the address at the start of the insn.  */
  dwarf2_emit_insn (0);

  /* Parse the instruction's operands.  */
  parse_insn (&crx_ins, param);

  /* Assemble the instruction - return upon failure.  */
  if (assemble_insn (op, &crx_ins) == 0)
    {
      param[-1] = c;
      return;
    }

  /* Print the instruction.  */
  param[-1] = c;
  print_insn (&crx_ins);
}