opcodes/ns32k-dis.c

   1 /* Print National Semiconductor 32000 instructions.
   2    Copyright (C) 1986-2019 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU opcodes library.
   5
   6    This library is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3, or (at your option)
   9    any later version.
  10
  11    It is distributed in the hope that it will be useful, but WITHOUT
  12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  14    License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "bfd.h"
  23 #include "disassemble.h"
  24 #if !defined(const) && !defined(__STDC__)
  25 #define const
  26 #endif
  27 #include "opcode/ns32k.h"
  28 #include "opintl.h"
  29
  30 static disassemble_info *dis_info;
  31
  32 /* Hacks to get it to compile <= READ THESE AS FIXES NEEDED.  */
  33 #define INVALID_FLOAT(val, size) invalid_float ((bfd_byte *) val, size)
  34
  35 static long
  36 read_memory_integer (unsigned char * addr, int nr)
  37 {
  38   long val;
  39   int i;
  40
  41   for (val = 0, i = nr - 1; i >= 0; i--)
  42     {
  43       val =  (val << 8);
  44       val |= (0xff & *(addr + i));
  45     }
  46   return val;
  47 }
  48
  49 /* 32000 instructions are never longer than this.  */
  50 #define MAXLEN 62
  51
  52 #include <setjmp.h>
  53
  54 struct private
  55 {
  56   /* Points to first byte not fetched.  */
  57   bfd_byte *max_fetched;
  58   bfd_byte the_buffer[MAXLEN];
  59   bfd_vma insn_start;
  60   OPCODES_SIGJMP_BUF bailout;
  61 };
  62
  63
  64 /* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive)
  65    to ADDR (exclusive) are valid.  Returns 1 for success, longjmps
  66    on error.  */
  67 #define FETCH_DATA(info, addr) \
  68   ((addr) <= ((struct private *)(info->private_data))->max_fetched \
  69    ? 1 : fetch_data ((info), (addr)))
  70
  71 static int
  72 fetch_data (struct disassemble_info *info, bfd_byte *addr)
  73 {
  74   int status;
  75   struct private *priv = (struct private *) info->private_data;
  76   bfd_vma start = priv->insn_start + (priv->max_fetched - priv->the_buffer);
  77
  78   status = (*info->read_memory_func) (start,
  79                                       priv->max_fetched,
  80                                       addr - priv->max_fetched,
  81                                       info);
  82   if (status != 0)
  83     {
  84       (*info->memory_error_func) (status, start, info);
  85       OPCODES_SIGLONGJMP (priv->bailout, 1);
  86     }
  87   else
  88     priv->max_fetched = addr;
  89   return 1;
  90 }
  91
  92 /* Number of elements in the opcode table.  */
  93 #define NOPCODES (sizeof ns32k_opcodes / sizeof ns32k_opcodes[0])
  94
  95 #define NEXT_IS_ADDR    '|'
  96
  97 \f
  98 struct ns32k_option
  99 {
 100   char *pattern;                /* The option itself.  */
 101   unsigned long value;          /* Binary value of the option.  */
 102   unsigned long match;          /* These bits must match.  */
 103 };
 104
 105 \f
 106 static const struct ns32k_option opt_u[]= /* Restore, exit.  */
 107 {
 108   { "r0",       0x80,   0x80    },
 109   { "r1",       0x40,   0x40    },
 110   { "r2",       0x20,   0x20    },
 111   { "r3",       0x10,   0x10    },
 112   { "r4",       0x08,   0x08    },
 113   { "r5",       0x04,   0x04    },
 114   { "r6",       0x02,   0x02    },
 115   { "r7",       0x01,   0x01    },
 116   {  0 ,        0x00,   0x00    }
 117 };
 118
 119 static const struct ns32k_option opt_U[]= /* Save, enter.  */
 120 {
 121   { "r0",       0x01,   0x01    },
 122   { "r1",       0x02,   0x02    },
 123   { "r2",       0x04,   0x04    },
 124   { "r3",       0x08,   0x08    },
 125   { "r4",       0x10,   0x10    },
 126   { "r5",       0x20,   0x20    },
 127   { "r6",       0x40,   0x40    },
 128   { "r7",       0x80,   0x80    },
 129   {  0 ,        0x00,   0x00    }
 130 };
 131
 132 static const struct ns32k_option opt_O[]= /* Setcfg.  */
 133 {
 134   { "c",        0x8,    0x8     },
 135   { "m",        0x4,    0x4     },
 136   { "f",        0x2,    0x2     },
 137   { "i",        0x1,    0x1     },
 138   {  0 ,        0x0,    0x0     }
 139 };
 140
 141 static const struct ns32k_option opt_C[]= /* Cinv.  */
 142 {
 143   { "a",        0x4,    0x4     },
 144   { "i",        0x2,    0x2     },
 145   { "d",        0x1,    0x1     },
 146   {  0 ,        0x0,    0x0     }
 147 };
 148
 149 static const struct ns32k_option opt_S[]= /* String inst.  */
 150 {
 151   { "b",        0x1,    0x1     },
 152   { "u",        0x6,    0x6     },
 153   { "w",        0x2,    0x2     },
 154   {  0 ,        0x0,    0x0     }
 155 };
 156
 157 static const struct ns32k_option list_P532[]= /* Lpr spr.  */
 158 {
 159   { "us",       0x0,    0xf     },
 160   { "dcr",      0x1,    0xf     },
 161   { "bpc",      0x2,    0xf     },
 162   { "dsr",      0x3,    0xf     },
 163   { "car",      0x4,    0xf     },
 164   { "fp",       0x8,    0xf     },
 165   { "sp",       0x9,    0xf     },
 166   { "sb",       0xa,    0xf     },
 167   { "usp",      0xb,    0xf     },
 168   { "cfg",      0xc,    0xf     },
 169   { "psr",      0xd,    0xf     },
 170   { "intbase",  0xe,    0xf     },
 171   { "mod",      0xf,    0xf     },
 172   {  0 ,        0x00,   0xf     }
 173 };
 174
 175 static const struct ns32k_option list_M532[]= /* Lmr smr.  */
 176 {
 177   { "mcr",      0x9,    0xf     },
 178   { "msr",      0xa,    0xf     },
 179   { "tear",     0xb,    0xf     },
 180   { "ptb0",     0xc,    0xf     },
 181   { "ptb1",     0xd,    0xf     },
 182   { "ivar0",    0xe,    0xf     },
 183   { "ivar1",    0xf,    0xf     },
 184   {  0 ,        0x0,    0xf     }
 185 };
 186
 187 static const struct ns32k_option list_P032[]= /* Lpr spr.  */
 188 {
 189   { "upsr",     0x0,    0xf     },
 190   { "fp",       0x8,    0xf     },
 191   { "sp",       0x9,    0xf     },
 192   { "sb",       0xa,    0xf     },
 193   { "psr",      0xb,    0xf     },
 194   { "intbase",  0xe,    0xf     },
 195   { "mod",      0xf,    0xf     },
 196   {  0 ,        0x0,    0xf     }
 197 };
 198
 199 static const struct ns32k_option list_M032[]= /* Lmr smr.  */
 200 {
 201   { "bpr0",     0x0,    0xf     },
 202   { "bpr1",     0x1,    0xf     },
 203   { "pf0",      0x4,    0xf     },
 204   { "pf1",      0x5,    0xf     },
 205   { "sc",       0x8,    0xf     },
 206   { "msr",      0xa,    0xf     },
 207   { "bcnt",     0xb,    0xf     },
 208   { "ptb0",     0xc,    0xf     },
 209   { "ptb1",     0xd,    0xf     },
 210   { "eia",      0xf,    0xf     },
 211   {  0 ,        0x0,    0xf     }
 212 };
 213
 214
 215 /* Figure out which options are present.   */
 216
 217 static void
 218 optlist (int options, const struct ns32k_option * optionP, char * result)
 219 {
 220   if (options == 0)
 221     {
 222       sprintf (result, "[]");
 223       return;
 224     }
 225
 226   sprintf (result, "[");
 227
 228   for (; (options != 0) && optionP->pattern; optionP++)
 229     {
 230       if ((options & optionP->match) == optionP->value)
 231         {
 232           /* We found a match, update result and options.  */
 233           strcat (result, optionP->pattern);
 234           options &= ~optionP->value;
 235           if (options != 0)     /* More options to come.  */
 236             strcat (result, ",");
 237         }
 238     }
 239
 240   if (options != 0)
 241     strcat (result, "undefined");
 242
 243   strcat (result, "]");
 244 }
 245
 246 static void
 247 list_search (int reg_value, const struct ns32k_option *optionP, char *result)
 248 {
 249   for (; optionP->pattern; optionP++)
 250     {
 251       if ((reg_value & optionP->match) == optionP->value)
 252         {
 253           sprintf (result, "%s", optionP->pattern);
 254           return;
 255         }
 256     }
 257   sprintf (result, "undefined");
 258 }
 259 \f
 260 /* Extract "count" bits starting "offset" bits into buffer.  */
 261
 262 static int
 263 bit_extract (bfd_byte *buffer, int offset, int count)
 264 {
 265   int result;
 266   int bit;
 267
 268   buffer += offset >> 3;
 269   offset &= 7;
 270   bit = 1;
 271   result = 0;
 272   while (count--)
 273     {
 274       FETCH_DATA (dis_info, buffer + 1);
 275       if ((*buffer & (1 << offset)))
 276         result |= bit;
 277       if (++offset == 8)
 278         {
 279           offset = 0;
 280           buffer++;
 281         }
 282       bit <<= 1;
 283     }
 284   return result;
 285 }
 286
 287 /* Like bit extract but the buffer is valid and doen't need to be fetched.  */
 288
 289 static int
 290 bit_extract_simple (bfd_byte *buffer, int offset, int count)
 291 {
 292   int result;
 293   int bit;
 294
 295   buffer += offset >> 3;
 296   offset &= 7;
 297   bit = 1;
 298   result = 0;
 299   while (count--)
 300     {
 301       if ((*buffer & (1 << offset)))
 302         result |= bit;
 303       if (++offset == 8)
 304         {
 305           offset = 0;
 306           buffer++;
 307         }
 308       bit <<= 1;
 309     }
 310   return result;
 311 }
 312
 313 static void
 314 bit_copy (bfd_byte *buffer, int offset, int count, char *to)
 315 {
 316   for (; count > 8; count -= 8, to++, offset += 8)
 317     *to = bit_extract (buffer, offset, 8);
 318   *to = bit_extract (buffer, offset, count);
 319 }
 320
 321 static int
 322 sign_extend (int value, int bits)
 323 {
 324   value = value & ((1 << bits) - 1);
 325   return (value & (1 << (bits - 1))
 326           ? value | (~((1 << bits) - 1))
 327           : value);
 328 }
 329
 330 static void
 331 flip_bytes (char *ptr, int count)
 332 {
 333   char tmp;
 334
 335   while (count > 0)
 336     {
 337       tmp = ptr[0];
 338       ptr[0] = ptr[count - 1];
 339       ptr[count - 1] = tmp;
 340       ptr++;
 341       count -= 2;
 342     }
 343 }
 344 \f
 345 /* Given a character C, does it represent a general addressing mode?  */
 346 #define Is_gen(c) \
 347   ((c) == 'F' || (c) == 'L' || (c) == 'B' \
 348    || (c) == 'W' || (c) == 'D' || (c) == 'A' || (c) == 'I' || (c) == 'Z')
 349
 350 /* Adressing modes.  */
 351 #define Adrmod_index_byte        0x1c
 352 #define Adrmod_index_word        0x1d
 353 #define Adrmod_index_doubleword  0x1e
 354 #define Adrmod_index_quadword    0x1f
 355
 356 /* Is MODE an indexed addressing mode?  */
 357 #define Adrmod_is_index(mode) \
 358   (   mode == Adrmod_index_byte \
 359    || mode == Adrmod_index_word \
 360    || mode == Adrmod_index_doubleword \
 361    || mode == Adrmod_index_quadword)
 362
 363 \f
 364 static int
 365 get_displacement (bfd_byte *buffer, int *aoffsetp)
 366 {
 367   int Ivalue;
 368   short Ivalue2;
 369
 370   Ivalue = bit_extract (buffer, *aoffsetp, 8);
 371   switch (Ivalue & 0xc0)
 372     {
 373     case 0x00:
 374     case 0x40:
 375       Ivalue = sign_extend (Ivalue, 7);
 376       *aoffsetp += 8;
 377       break;
 378     case 0x80:
 379       Ivalue2 = bit_extract (buffer, *aoffsetp, 16);
 380       flip_bytes ((char *) & Ivalue2, 2);
 381       Ivalue = sign_extend (Ivalue2, 14);
 382       *aoffsetp += 16;
 383       break;
 384     case 0xc0:
 385       Ivalue = bit_extract (buffer, *aoffsetp, 32);
 386       flip_bytes ((char *) & Ivalue, 4);
 387       Ivalue = sign_extend (Ivalue, 30);
 388       *aoffsetp += 32;
 389       break;
 390     }
 391   return Ivalue;
 392 }
 393
 394 #if 1 /* A version that should work on ns32k f's&d's on any machine.  */
 395 static int
 396 invalid_float (bfd_byte *p, int len)
 397 {
 398   int val;
 399
 400   if (len == 4)
 401     val = (bit_extract_simple (p, 23, 8)/*exponent*/ == 0xff
 402            || (bit_extract_simple (p, 23, 8)/*exponent*/ == 0
 403                && bit_extract_simple (p, 0, 23)/*mantisa*/ != 0));
 404   else if (len == 8)
 405     val = (bit_extract_simple (p, 52, 11)/*exponent*/ == 0x7ff
 406            || (bit_extract_simple (p, 52, 11)/*exponent*/ == 0
 407                && (bit_extract_simple (p, 0, 32)/*low mantisa*/ != 0
 408                    || bit_extract_simple (p, 32, 20)/*high mantisa*/ != 0)));
 409   else
 410     val = 1;
 411   return (val);
 412 }
 413 #else
 414 /* Assumes the bytes have been swapped to local order.  */
 415 typedef union
 416 {
 417   double d;
 418   float f;
 419   struct { unsigned m:23, e:8, :1;} sf;
 420   struct { unsigned lm; unsigned m:20, e:11, :1;} sd;
 421 } float_type_u;
 422
 423 static int
 424 invalid_float (float_type_u *p, int len)
 425 {
 426   int val;
 427
 428   if (len == sizeof (float))
 429     val = (p->sf.e == 0xff
 430            || (p->sf.e == 0 && p->sf.m != 0));
 431   else if (len == sizeof (double))
 432     val = (p->sd.e == 0x7ff
 433            || (p->sd.e == 0 && (p->sd.m != 0 || p->sd.lm != 0)));
 434   else
 435     val = 1;
 436   return val;
 437 }
 438 #endif
 439
 440 /* Print an instruction operand of category given by d.  IOFFSET is
 441    the bit position below which small (<1 byte) parts of the operand can
 442    be found (usually in the basic instruction, but for indexed
 443    addressing it can be in the index byte).  AOFFSETP is a pointer to the
 444    bit position of the addressing extension.  BUFFER contains the
 445    instruction.  ADDR is where BUFFER was read from.  Put the disassembled
 446    version of the operand in RESULT.  INDEX_OFFSET is the bit position
 447    of the index byte (it contains garbage if this operand is not a
 448    general operand using scaled indexed addressing mode).  */
 449
 450 static int
 451 print_insn_arg (int d,
 452                 int ioffset,
 453                 int *aoffsetp,
 454                 bfd_byte *buffer,
 455                 bfd_vma addr,
 456                 char *result,
 457                 int index_offset)
 458 {
 459   union
 460   {
 461     float f;
 462     double d;
 463     int i[2];
 464   } value;
 465   int Ivalue;
 466   int addr_mode;
 467   int disp1, disp2;
 468   int size;
 469
 470   switch (d)
 471     {
 472     case 'f':
 473       /* A "gen" operand but 5 bits from the end of instruction.  */
 474       ioffset -= 5;
 475       /* Fall through.  */
 476     case 'Z':
 477     case 'F':
 478     case 'L':
 479     case 'I':
 480     case 'B':
 481     case 'W':
 482     case 'D':
 483     case 'A':
 484       addr_mode = bit_extract (buffer, ioffset - 5, 5);
 485       ioffset -= 5;
 486       switch (addr_mode)
 487         {
 488         case 0x0: case 0x1: case 0x2: case 0x3:
 489         case 0x4: case 0x5: case 0x6: case 0x7:
 490           /* Register mode R0 -- R7.  */
 491           switch (d)
 492             {
 493             case 'F':
 494             case 'L':
 495             case 'Z':
 496               sprintf (result, "f%d", addr_mode);
 497               break;
 498             default:
 499               sprintf (result, "r%d", addr_mode);
 500             }
 501           break;
 502         case 0x8: case 0x9: case 0xa: case 0xb:
 503         case 0xc: case 0xd: case 0xe: case 0xf:
 504           /* Register relative disp(R0 -- R7).  */
 505           disp1 = get_displacement (buffer, aoffsetp);
 506           sprintf (result, "%d(r%d)", disp1, addr_mode & 7);
 507           break;
 508         case 0x10:
 509         case 0x11:
 510         case 0x12:
 511           /* Memory relative disp2(disp1(FP, SP, SB)).  */
 512           disp1 = get_displacement (buffer, aoffsetp);
 513           disp2 = get_displacement (buffer, aoffsetp);
 514           sprintf (result, "%d(%d(%s))", disp2, disp1,
 515                    addr_mode == 0x10 ? "fp" : addr_mode == 0x11 ? "sp" : "sb");
 516           break;
 517         case 0x13:
 518           /* Reserved.  */
 519           sprintf (result, "reserved");
 520           break;
 521         case 0x14:
 522           /* Immediate.  */
 523           switch (d)
 524             {
 525             case 'I':
 526             case 'Z':
 527             case 'A':
 528               /* I and Z are output operands and can`t be immediate
 529                  A is an address and we can`t have the address of
 530                  an immediate either. We don't know how much to increase
 531                  aoffsetp by since whatever generated this is broken
 532                  anyway!  */
 533               sprintf (result, _("$<undefined>"));
 534               break;
 535             case 'B':
 536               Ivalue = bit_extract (buffer, *aoffsetp, 8);
 537               Ivalue = sign_extend (Ivalue, 8);
 538               *aoffsetp += 8;
 539               sprintf (result, "$%d", Ivalue);
 540               break;
 541             case 'W':
 542               Ivalue = bit_extract (buffer, *aoffsetp, 16);
 543               flip_bytes ((char *) & Ivalue, 2);
 544               *aoffsetp += 16;
 545               Ivalue = sign_extend (Ivalue, 16);
 546               sprintf (result, "$%d", Ivalue);
 547               break;
 548             case 'D':
 549               Ivalue = bit_extract (buffer, *aoffsetp, 32);
 550               flip_bytes ((char *) & Ivalue, 4);
 551               *aoffsetp += 32;
 552               sprintf (result, "$%d", Ivalue);
 553               break;
 554             case 'F':
 555               bit_copy (buffer, *aoffsetp, 32, (char *) &value.f);
 556               flip_bytes ((char *) &value.f, 4);
 557               *aoffsetp += 32;
 558               if (INVALID_FLOAT (&value.f, 4))
 559                 sprintf (result, "<<invalid float 0x%.8x>>", value.i[0]);
 560               else /* Assume host has ieee float.  */
 561                 sprintf (result, "$%g", value.f);
 562               break;
 563             case 'L':
 564               bit_copy (buffer, *aoffsetp, 64, (char *) &value.d);
 565               flip_bytes ((char *) &value.d, 8);
 566               *aoffsetp += 64;
 567               if (INVALID_FLOAT (&value.d, 8))
 568                 sprintf (result, "<<invalid double 0x%.8x%.8x>>",
 569                          value.i[1], value.i[0]);
 570               else /* Assume host has ieee float.  */
 571                 sprintf (result, "$%g", value.d);
 572               break;
 573             }
 574           break;
 575         case 0x15:
 576           /* Absolute @disp.  */
 577           disp1 = get_displacement (buffer, aoffsetp);
 578           sprintf (result, "@|%d|", disp1);
 579           break;
 580         case 0x16:
 581           /* External EXT(disp1) + disp2 (Mod table stuff).  */
 582           disp1 = get_displacement (buffer, aoffsetp);
 583           disp2 = get_displacement (buffer, aoffsetp);
 584           sprintf (result, "EXT(%d) + %d", disp1, disp2);
 585           break;
 586         case 0x17:
 587           /* Top of stack tos.  */
 588           sprintf (result, "tos");
 589           break;
 590         case 0x18:
 591           /* Memory space disp(FP).  */
 592           disp1 = get_displacement (buffer, aoffsetp);
 593           sprintf (result, "%d(fp)", disp1);
 594           break;
 595         case 0x19:
 596           /* Memory space disp(SP).  */
 597           disp1 = get_displacement (buffer, aoffsetp);
 598           sprintf (result, "%d(sp)", disp1);
 599           break;
 600         case 0x1a:
 601           /* Memory space disp(SB).  */
 602           disp1 = get_displacement (buffer, aoffsetp);
 603           sprintf (result, "%d(sb)", disp1);
 604           break;
 605         case 0x1b:
 606           /* Memory space disp(PC).  */
 607           disp1 = get_displacement (buffer, aoffsetp);
 608           *result++ = NEXT_IS_ADDR;
 609           sprintf_vma (result, addr + disp1);
 610           result += strlen (result);
 611           *result++ = NEXT_IS_ADDR;
 612           *result = '\0';
 613           break;
 614         case 0x1c:
 615         case 0x1d:
 616         case 0x1e:
 617         case 0x1f:
 618           {
 619             int bit_index;
 620             static const char *ind = "bwdq";
 621             char *off;
 622
 623             /* Scaled index basemode[R0 -- R7:B,W,D,Q].  */
 624             bit_index = bit_extract (buffer, index_offset - 8, 3);
 625             print_insn_arg (d, index_offset, aoffsetp, buffer, addr,
 626                             result, 0);
 627             off = result + strlen (result);
 628             sprintf (off, "[r%d:%c]", bit_index, ind[addr_mode & 3]);
 629           }
 630           break;
 631         }
 632       break;
 633     case 'H':
 634     case 'q':
 635       Ivalue = bit_extract (buffer, ioffset-4, 4);
 636       Ivalue = sign_extend (Ivalue, 4);
 637       sprintf (result, "%d", Ivalue);
 638       ioffset -= 4;
 639       break;
 640     case 'r':
 641       Ivalue = bit_extract (buffer, ioffset-3, 3);
 642       sprintf (result, "r%d", Ivalue&7);
 643       ioffset -= 3;
 644       break;
 645     case 'd':
 646       sprintf (result, "%d", get_displacement (buffer, aoffsetp));
 647       break;
 648     case 'b':
 649       Ivalue = get_displacement (buffer, aoffsetp);
 650       /* Warning!!  HACK ALERT!
 651          Operand type 'b' is only used by the cmp{b,w,d} and
 652          movm{b,w,d} instructions; we need to know whether
 653          it's a `b' or `w' or `d' instruction; and for both
 654          cmpm and movm it's stored at the same place so we
 655          just grab two bits of the opcode and look at it...  */
 656       size = bit_extract(buffer, ioffset-6, 2);
 657       if (size == 0)            /* 00 => b.  */
 658         size = 1;
 659       else if (size == 1)       /* 01 => w.  */
 660         size = 2;
 661       else
 662         size = 4;               /* 11 => d.  */
 663
 664       sprintf (result, "%d", (Ivalue / size) + 1);
 665       break;
 666     case 'p':
 667       *result++ = NEXT_IS_ADDR;
 668       sprintf_vma (result, addr + get_displacement (buffer, aoffsetp));
 669       result += strlen (result);
 670       *result++ = NEXT_IS_ADDR;
 671       *result = '\0';
 672       break;
 673     case 'i':
 674       Ivalue = bit_extract (buffer, *aoffsetp, 8);
 675       *aoffsetp += 8;
 676       sprintf (result, "0x%x", Ivalue);
 677       break;
 678     case 'u':
 679       Ivalue = bit_extract (buffer, *aoffsetp, 8);
 680       optlist (Ivalue, opt_u, result);
 681       *aoffsetp += 8;
 682       break;
 683     case 'U':
 684       Ivalue = bit_extract (buffer, *aoffsetp, 8);
 685       optlist (Ivalue, opt_U, result);
 686       *aoffsetp += 8;
 687       break;
 688     case 'O':
 689       Ivalue = bit_extract (buffer, ioffset - 9, 9);
 690       optlist (Ivalue, opt_O, result);
 691       ioffset -= 9;
 692       break;
 693     case 'C':
 694       Ivalue = bit_extract (buffer, ioffset - 4, 4);
 695       optlist (Ivalue, opt_C, result);
 696       ioffset -= 4;
 697       break;
 698     case 'S':
 699       Ivalue = bit_extract (buffer, ioffset - 8, 8);
 700       optlist (Ivalue, opt_S, result);
 701       ioffset -= 8;
 702       break;
 703     case 'M':
 704       Ivalue = bit_extract (buffer, ioffset - 4, 4);
 705       list_search (Ivalue, 0 ? list_M032 : list_M532, result);
 706       ioffset -= 4;
 707       break;
 708     case 'P':
 709       Ivalue = bit_extract (buffer, ioffset - 4, 4);
 710       list_search (Ivalue, 0 ? list_P032 : list_P532, result);
 711       ioffset -= 4;
 712       break;
 713     case 'g':
 714       Ivalue = bit_extract (buffer, *aoffsetp, 3);
 715       sprintf (result, "%d", Ivalue);
 716       *aoffsetp += 3;
 717       break;
 718     case 'G':
 719       Ivalue = bit_extract(buffer, *aoffsetp, 5);
 720       sprintf (result, "%d", Ivalue + 1);
 721       *aoffsetp += 5;
 722       break;
 723     }
 724   return ioffset;
 725 }
 726
 727 \f
 728 /* Print the 32000 instruction at address MEMADDR in debugged memory,
 729    on STREAM.  Returns length of the instruction, in bytes.  */
 730
 731 int
 732 print_insn_ns32k (bfd_vma memaddr, disassemble_info *info)
 733 {
 734   unsigned int i;
 735   const char *d;
 736   unsigned short first_word;
 737   int ioffset;          /* Bits into instruction.  */
 738   int aoffset;          /* Bits into arguments.  */
 739   char arg_bufs[MAX_ARGS+1][ARG_LEN];
 740   int argnum;
 741   int maxarg;
 742   struct private priv;
 743   bfd_byte *buffer = priv.the_buffer;
 744   dis_info = info;
 745
 746   info->private_data = & priv;
 747   priv.max_fetched = priv.the_buffer;
 748   priv.insn_start = memaddr;
 749   if (OPCODES_SIGSETJMP (priv.bailout) != 0)
 750     /* Error return.  */
 751     return -1;
 752
 753   /* Look for 8bit opcodes first. Other wise, fetching two bytes could take
 754      us over the end of accessible data unnecessarilly.  */
 755   FETCH_DATA (info, buffer + 1);
 756   for (i = 0; i < NOPCODES; i++)
 757     if (ns32k_opcodes[i].opcode_id_size <= 8
 758         && ((buffer[0]
 759              & (((unsigned long) 1 << ns32k_opcodes[i].opcode_id_size) - 1))
 760             == ns32k_opcodes[i].opcode_seed))
 761       break;
 762   if (i == NOPCODES)
 763     {
 764       /* Maybe it is 9 to 16 bits big.  */
 765       FETCH_DATA (info, buffer + 2);
 766       first_word = read_memory_integer(buffer, 2);
 767
 768       for (i = 0; i < NOPCODES; i++)
 769         if ((first_word
 770              & (((unsigned long) 1 << ns32k_opcodes[i].opcode_id_size) - 1))
 771             == ns32k_opcodes[i].opcode_seed)
 772           break;
 773
 774       /* Handle undefined instructions.  */
 775       if (i == NOPCODES)
 776         {
 777           (*dis_info->fprintf_func)(dis_info->stream, "0%o", buffer[0]);
 778           return 1;
 779         }
 780     }
 781
 782   (*dis_info->fprintf_func)(dis_info->stream, "%s", ns32k_opcodes[i].name);
 783
 784   ioffset = ns32k_opcodes[i].opcode_size;
 785   aoffset = ns32k_opcodes[i].opcode_size;
 786   d = ns32k_opcodes[i].operands;
 787
 788   if (*d)
 789     {
 790       /* Offset in bits of the first thing beyond each index byte.
 791          Element 0 is for operand A and element 1 is for operand B.
 792          The rest are irrelevant, but we put them here so we don't
 793          index outside the array.  */
 794       int index_offset[MAX_ARGS];
 795
 796       /* 0 for operand A, 1 for operand B, greater for other args.  */
 797       int whicharg = 0;
 798
 799       (*dis_info->fprintf_func)(dis_info->stream, "\t");
 800
 801       maxarg = 0;
 802
 803       /* First we have to find and keep track of the index bytes,
 804          if we are using scaled indexed addressing mode, since the index
 805          bytes occur right after the basic instruction, not as part
 806          of the addressing extension.  */
 807       if (Is_gen(d[1]))
 808         {
 809           int addr_mode = bit_extract (buffer, ioffset - 5, 5);
 810
 811           if (Adrmod_is_index (addr_mode))
 812             {
 813               aoffset += 8;
 814               index_offset[0] = aoffset;
 815             }
 816         }
 817
 818       if (d[2] && Is_gen(d[3]))
 819         {
 820           int addr_mode = bit_extract (buffer, ioffset - 10, 5);
 821
 822           if (Adrmod_is_index (addr_mode))
 823             {
 824               aoffset += 8;
 825               index_offset[1] = aoffset;
 826             }
 827         }
 828
 829       while (*d)
 830         {
 831           argnum = *d - '1';
 832           d++;
 833           if (argnum > maxarg && argnum < MAX_ARGS)
 834             maxarg = argnum;
 835           ioffset = print_insn_arg (*d, ioffset, &aoffset, buffer,
 836                                     memaddr, arg_bufs[argnum],
 837                                     index_offset[whicharg]);
 838           d++;
 839           whicharg++;
 840         }
 841       for (argnum = 0; argnum <= maxarg; argnum++)
 842         {
 843           bfd_vma addr;
 844           char *ch;
 845
 846           for (ch = arg_bufs[argnum]; *ch;)
 847             {
 848               if (*ch == NEXT_IS_ADDR)
 849                 {
 850                   ++ch;
 851                   addr = bfd_scan_vma (ch, NULL, 16);
 852                   (*dis_info->print_address_func) (addr, dis_info);
 853                   while (*ch && *ch != NEXT_IS_ADDR)
 854                     ++ch;
 855                   if (*ch)
 856                     ++ch;
 857                 }
 858               else
 859                 (*dis_info->fprintf_func)(dis_info->stream, "%c", *ch++);
 860             }
 861           if (argnum < maxarg)
 862             (*dis_info->fprintf_func)(dis_info->stream, ", ");
 863         }
 864     }
 865   return aoffset / 8;
 866 }