opcodes/z8k-dis.c

   1 /* Disassemble z8000 code.
   2    Copyright (C) 1992-2020 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 file; see the file COPYING.  If not, write to the
  18    Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "disassemble.h"
  23
  24 #define DEFINE_TABLE
  25 #include "z8k-opc.h"
  26
  27 #include <setjmp.h>
  28
  29 typedef struct
  30 {
  31   /* These are all indexed by nibble number (i.e only every other entry
  32      of bytes is used, and every 4th entry of words).  */
  33   unsigned char nibbles[24];
  34   unsigned char bytes[24];
  35   unsigned short words[24];
  36
  37   /* Nibble number of first word not yet fetched.  */
  38   int max_fetched;
  39   bfd_vma insn_start;
  40   OPCODES_SIGJMP_BUF bailout;
  41
  42   int tabl_index;
  43   char instr_asmsrc[80];
  44   unsigned long arg_reg[0x0f];
  45   unsigned long immediate;
  46   unsigned long displacement;
  47   unsigned long address;
  48   unsigned long cond_code;
  49   unsigned long ctrl_code;
  50   unsigned long flags;
  51   unsigned long interrupts;
  52 }
  53 instr_data_s;
  54
  55 /* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive)
  56    to ADDR (exclusive) are valid.  Returns 1 for success, longjmps
  57    on error.  */
  58 #define FETCH_DATA(info, nibble) \
  59   ((nibble) < ((instr_data_s *) (info->private_data))->max_fetched \
  60    ? 1 : fetch_data ((info), (nibble)))
  61
  62 static int
  63 fetch_data (struct disassemble_info *info, int nibble)
  64 {
  65   unsigned char mybuf[20];
  66   int status;
  67   instr_data_s *priv = (instr_data_s *) info->private_data;
  68
  69   if ((nibble % 4) != 0)
  70     abort ();
  71
  72   status = (*info->read_memory_func) (priv->insn_start,
  73                                       (bfd_byte *) mybuf,
  74                                       nibble / 2,
  75                                       info);
  76   if (status != 0)
  77     {
  78       (*info->memory_error_func) (status, priv->insn_start, info);
  79       OPCODES_SIGLONGJMP (priv->bailout, 1);
  80     }
  81
  82   {
  83     int i;
  84     unsigned char *p = mybuf;
  85
  86     for (i = 0; i < nibble;)
  87       {
  88         priv->words[i] = (p[0] << 8) | p[1];
  89
  90         priv->bytes[i] = *p;
  91         priv->nibbles[i++] = *p >> 4;
  92         priv->nibbles[i++] = *p & 0xf;
  93
  94         ++p;
  95         priv->bytes[i] = *p;
  96         priv->nibbles[i++] = *p >> 4;
  97         priv->nibbles[i++] = *p & 0xf;
  98
  99         ++p;
 100       }
 101   }
 102   priv->max_fetched = nibble;
 103   return 1;
 104 }
 105
 106 static char *codes[16] =
 107   {
 108     "f",
 109     "lt",
 110     "le",
 111     "ule",
 112     "ov/pe",
 113     "mi",
 114     "eq",
 115     "c/ult",
 116     "t",
 117     "ge",
 118     "gt",
 119     "ugt",
 120     "nov/po",
 121     "pl",
 122     "ne",
 123     "nc/uge"
 124   };
 125
 126 static char *ctrl_names[8] =
 127   {
 128     "<invld>",
 129     "flags",
 130     "fcw",
 131     "refresh",
 132     "psapseg",
 133     "psapoff",
 134     "nspseg",
 135     "nspoff"
 136   };
 137
 138 static int seg_length;
 139 int z8k_lookup_instr (unsigned char *, disassemble_info *);
 140 static void output_instr (instr_data_s *, unsigned long, disassemble_info *);
 141 static void unpack_instr (instr_data_s *, int, disassemble_info *);
 142 static void unparse_instr (instr_data_s *, int);
 143
 144 static int
 145 print_insn_z8k (bfd_vma addr, disassemble_info *info, int is_segmented)
 146 {
 147   instr_data_s instr_data;
 148
 149   info->private_data = (PTR) &instr_data;
 150   instr_data.max_fetched = 0;
 151   instr_data.insn_start = addr;
 152   if (OPCODES_SIGSETJMP (instr_data.bailout) != 0)
 153     /* Error return.  */
 154     return -1;
 155
 156   info->bytes_per_chunk = 2;
 157   info->bytes_per_line = 6;
 158   info->display_endian = BFD_ENDIAN_BIG;
 159
 160   instr_data.tabl_index = z8k_lookup_instr (instr_data.nibbles, info);
 161   if (instr_data.tabl_index >= 0)
 162     {
 163       unpack_instr (&instr_data, is_segmented, info);
 164       unparse_instr (&instr_data, is_segmented);
 165       output_instr (&instr_data, addr, info);
 166       return z8k_table[instr_data.tabl_index].length + seg_length;
 167     }
 168   else
 169     {
 170       FETCH_DATA (info, 4);
 171       (*info->fprintf_func) (info->stream, ".word %02x%02x",
 172                              instr_data.bytes[0], instr_data.bytes[2]);
 173       return 2;
 174     }
 175 }
 176
 177 int
 178 print_insn_z8001 (bfd_vma addr, disassemble_info *info)
 179 {
 180   return print_insn_z8k (addr, info, 1);
 181 }
 182
 183 int
 184 print_insn_z8002 (bfd_vma addr, disassemble_info *info)
 185 {
 186   return print_insn_z8k (addr, info, 0);
 187 }
 188
 189 int
 190 z8k_lookup_instr (unsigned char *nibbles, disassemble_info *info)
 191 {
 192   int nibl_index, tabl_index;
 193   int nibl_matched;
 194   int need_fetch = 0;
 195   unsigned short instr_nibl;
 196   unsigned short tabl_datum, datum_class, datum_value;
 197
 198   nibl_matched = 0;
 199   tabl_index = 0;
 200   FETCH_DATA (info, 4);
 201   while (!nibl_matched && z8k_table[tabl_index].name)
 202     {
 203       nibl_matched = 1;
 204       for (nibl_index = 0;
 205            nibl_index < z8k_table[tabl_index].length * 2 && nibl_matched;
 206            nibl_index++)
 207         {
 208           if ((nibl_index % 4) == 0)
 209             {
 210               /* Fetch data only if it isn't already there.  */
 211               if (nibl_index >= 4 || (nibl_index < 4 && need_fetch))
 212                 FETCH_DATA (info, nibl_index + 4);   /* Fetch one word at a time.  */
 213               if (nibl_index < 4)
 214                 need_fetch = 0;
 215               else
 216                 need_fetch = 1;
 217             }
 218           instr_nibl = nibbles[nibl_index];
 219
 220           tabl_datum = z8k_table[tabl_index].byte_info[nibl_index];
 221           datum_class = tabl_datum & CLASS_MASK;
 222           datum_value = ~CLASS_MASK & tabl_datum;
 223
 224           switch (datum_class)
 225             {
 226             case CLASS_BIT:
 227               if (datum_value != instr_nibl)
 228                 nibl_matched = 0;
 229               break;
 230             case CLASS_IGNORE:
 231               break;
 232             case CLASS_00II:
 233               if (!((~instr_nibl) & 0x4))
 234                 nibl_matched = 0;
 235               break;
 236             case CLASS_01II:
 237               if (!(instr_nibl & 0x4))
 238                 nibl_matched = 0;
 239               break;
 240             case CLASS_0CCC:
 241               if (!((~instr_nibl) & 0x8))
 242                 nibl_matched = 0;
 243               break;
 244             case CLASS_1CCC:
 245               if (!(instr_nibl & 0x8))
 246                 nibl_matched = 0;
 247               break;
 248             case CLASS_0DISP7:
 249               if (!((~instr_nibl) & 0x8))
 250                 nibl_matched = 0;
 251               nibl_index += 1;
 252               break;
 253             case CLASS_1DISP7:
 254               if (!(instr_nibl & 0x8))
 255                 nibl_matched = 0;
 256               nibl_index += 1;
 257               break;
 258             case CLASS_REGN0:
 259               if (instr_nibl == 0)
 260                 nibl_matched = 0;
 261               break;
 262             case CLASS_BIT_1OR2:
 263               if ((instr_nibl | 0x2) != (datum_value | 0x2))
 264                 nibl_matched = 0;
 265               break;
 266             default:
 267               break;
 268             }
 269         }
 270
 271       if (nibl_matched)
 272         return tabl_index;
 273
 274       tabl_index++;
 275     }
 276   return -1;
 277 }
 278
 279 static void
 280 output_instr (instr_data_s *instr_data,
 281               unsigned long addr ATTRIBUTE_UNUSED,
 282               disassemble_info *info)
 283 {
 284   int num_bytes;
 285   char out_str[100];
 286
 287   out_str[0] = 0;
 288
 289   num_bytes = (z8k_table[instr_data->tabl_index].length + seg_length) * 2;
 290   FETCH_DATA (info, num_bytes);
 291
 292   strcat (out_str, instr_data->instr_asmsrc);
 293
 294   (*info->fprintf_func) (info->stream, "%s", out_str);
 295 }
 296
 297 static void
 298 unpack_instr (instr_data_s *instr_data, int is_segmented, disassemble_info *info)
 299 {
 300   int nibl_count, loop;
 301   unsigned short instr_nibl, instr_byte, instr_word;
 302   long instr_long;
 303   unsigned int tabl_datum, datum_class;
 304   unsigned short datum_value;
 305
 306   nibl_count = 0;
 307   loop = 0;
 308   seg_length = 0;
 309
 310   while (z8k_table[instr_data->tabl_index].byte_info[loop] != 0)
 311     {
 312       FETCH_DATA (info, nibl_count + 4 - (nibl_count % 4));
 313       instr_nibl = instr_data->nibbles[nibl_count];
 314       instr_byte = instr_data->bytes[nibl_count & ~1];
 315       instr_word = instr_data->words[nibl_count & ~3];
 316
 317       tabl_datum = z8k_table[instr_data->tabl_index].byte_info[loop];
 318       datum_class = tabl_datum & CLASS_MASK;
 319       datum_value = tabl_datum & ~CLASS_MASK;
 320
 321       switch (datum_class)
 322         {
 323         case CLASS_DISP:
 324           switch (datum_value)
 325             {
 326             case ARG_DISP16:
 327               instr_data->displacement = instr_data->insn_start + 4
 328                 + (signed short) (instr_word & 0xffff);
 329               nibl_count += 3;
 330               break;
 331             case ARG_DISP12:
 332               if (instr_word & 0x800)
 333                 /* Negative 12 bit displacement.  */
 334                 instr_data->displacement = instr_data->insn_start + 2
 335                   - (signed short) ((instr_word & 0xfff) | 0xf000) * 2;
 336               else
 337                 instr_data->displacement = instr_data->insn_start + 2
 338                   - (instr_word & 0x0fff) * 2;
 339
 340               nibl_count += 2;
 341               break;
 342             default:
 343               break;
 344             }
 345           break;
 346         case CLASS_IMM:
 347           switch (datum_value)
 348             {
 349             case ARG_IMM4:
 350               instr_data->immediate = instr_nibl;
 351               break;
 352             case ARG_NIM4:
 353               instr_data->immediate = (- instr_nibl) & 0xf;
 354               break;
 355             case ARG_NIM8:
 356               instr_data->immediate = (- instr_byte) & 0xff;
 357               nibl_count += 1;
 358               break;
 359             case ARG_IMM8:
 360               instr_data->immediate = instr_byte;
 361               nibl_count += 1;
 362               break;
 363             case ARG_IMM16:
 364               instr_data->immediate = instr_word;
 365               nibl_count += 3;
 366               break;
 367             case ARG_IMM32:
 368               FETCH_DATA (info, nibl_count + 8);
 369               instr_long = (instr_data->words[nibl_count] << 16)
 370                 | (instr_data->words[nibl_count + 4]);
 371               instr_data->immediate = instr_long;
 372               nibl_count += 7;
 373               break;
 374             case ARG_IMMN:
 375               instr_data->immediate = instr_nibl - 1;
 376               break;
 377             case ARG_IMM4M1:
 378               instr_data->immediate = instr_nibl + 1;
 379               break;
 380             case ARG_IMM_1:
 381               instr_data->immediate = 1;
 382               break;
 383             case ARG_IMM_2:
 384               instr_data->immediate = 2;
 385               break;
 386             case ARG_IMM2:
 387               instr_data->immediate = instr_nibl & 0x3;
 388               break;
 389             default:
 390               break;
 391             }
 392           break;
 393         case CLASS_CC:
 394           instr_data->cond_code = instr_nibl;
 395           break;
 396         case CLASS_ADDRESS:
 397           if (is_segmented)
 398             {
 399               if (instr_nibl & 0x8)
 400                 {
 401                   FETCH_DATA (info, nibl_count + 8);
 402                   instr_long = (instr_data->words[nibl_count] << 16)
 403                     | (instr_data->words[nibl_count + 4]);
 404                   instr_data->address = ((instr_word & 0x7f00) << 16)
 405                     + (instr_long & 0xffff);
 406                   nibl_count += 7;
 407                   seg_length = 2;
 408                 }
 409               else
 410                 {
 411                   instr_data->address = ((instr_word & 0x7f00) << 16)
 412                     + (instr_word & 0x00ff);
 413                   nibl_count += 3;
 414                 }
 415             }
 416           else
 417             {
 418               instr_data->address = instr_word;
 419               nibl_count += 3;
 420             }
 421           break;
 422         case CLASS_0CCC:
 423         case CLASS_1CCC:
 424           instr_data->ctrl_code = instr_nibl & 0x7;
 425           break;
 426         case CLASS_0DISP7:
 427           instr_data->displacement =
 428             instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
 429           nibl_count += 1;
 430           break;
 431         case CLASS_1DISP7:
 432           instr_data->displacement =
 433             instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
 434           nibl_count += 1;
 435           break;
 436         case CLASS_01II:
 437           instr_data->interrupts = instr_nibl & 0x3;
 438           break;
 439         case CLASS_00II:
 440           instr_data->interrupts = instr_nibl & 0x3;
 441           break;
 442         case CLASS_IGNORE:
 443         case CLASS_BIT:
 444           instr_data->ctrl_code = instr_nibl & 0x7;
 445           break;
 446         case CLASS_FLAGS:
 447           instr_data->flags = instr_nibl;
 448           break;
 449         case CLASS_REG:
 450           instr_data->arg_reg[datum_value] = instr_nibl;
 451           break;
 452         case CLASS_REGN0:
 453           instr_data->arg_reg[datum_value] = instr_nibl;
 454           break;
 455         case CLASS_DISP8:
 456           instr_data->displacement =
 457             instr_data->insn_start + 2 + (signed char) instr_byte * 2;
 458           nibl_count += 1;
 459           break;
 460         case CLASS_BIT_1OR2:
 461           instr_data->immediate = ((instr_nibl >> 1) & 0x1) + 1;
 462           nibl_count += 1;
 463           break;
 464         default:
 465           abort ();
 466           break;
 467         }
 468
 469       loop += 1;
 470       nibl_count += 1;
 471     }
 472 }
 473
 474 static void
 475 print_intr(char *tmp_str, unsigned long interrupts)
 476 {
 477   int comma = 0;
 478
 479   *tmp_str = 0;
 480   if (! (interrupts & 2))
 481     {
 482       strcat (tmp_str, "vi");
 483       comma = 1;
 484     }
 485   if (! (interrupts & 1))
 486     {
 487       if (comma) strcat (tmp_str, ",");
 488       strcat (tmp_str, "nvi");
 489     }
 490 }
 491
 492 static void
 493 print_flags(char *tmp_str, unsigned long flags)
 494 {
 495   int comma = 0;
 496
 497   *tmp_str = 0;
 498   if (flags & 8)
 499     {
 500       strcat (tmp_str, "c");
 501       comma = 1;
 502     }
 503   if (flags & 4)
 504     {
 505       if (comma) strcat (tmp_str, ",");
 506       strcat (tmp_str, "z");
 507       comma = 1;
 508     }
 509   if (flags & 2)
 510     {
 511       if (comma) strcat (tmp_str, ",");
 512       strcat (tmp_str, "s");
 513       comma = 1;
 514     }
 515   if (flags & 1)
 516     {
 517       if (comma) strcat (tmp_str, ",");
 518       strcat (tmp_str, "p");
 519     }
 520 }
 521
 522 static void
 523 unparse_instr (instr_data_s *instr_data, int is_segmented)
 524 {
 525   unsigned short datum_value;
 526   unsigned int tabl_datum, datum_class;
 527   int loop, loop_limit;
 528   char out_str[80], tmp_str[25];
 529
 530   sprintf (out_str, "%s\t", z8k_table[instr_data->tabl_index].name);
 531
 532   loop_limit = z8k_table[instr_data->tabl_index].noperands;
 533   for (loop = 0; loop < loop_limit; loop++)
 534     {
 535       if (loop)
 536         strcat (out_str, ",");
 537
 538       tabl_datum = z8k_table[instr_data->tabl_index].arg_info[loop];
 539       datum_class = tabl_datum & CLASS_MASK;
 540       datum_value = tabl_datum & ~CLASS_MASK;
 541
 542       switch (datum_class)
 543         {
 544         case CLASS_X:
 545           sprintf (tmp_str, "0x%0lx(r%ld)", instr_data->address,
 546                    instr_data->arg_reg[datum_value]);
 547           strcat (out_str, tmp_str);
 548           break;
 549         case CLASS_BA:
 550           if (is_segmented)
 551             sprintf (tmp_str, "rr%ld(#0x%lx)", instr_data->arg_reg[datum_value],
 552                      instr_data->immediate);
 553           else
 554             sprintf (tmp_str, "r%ld(#0x%lx)", instr_data->arg_reg[datum_value],
 555                      instr_data->immediate);
 556           strcat (out_str, tmp_str);
 557           break;
 558         case CLASS_BX:
 559           if (is_segmented)
 560             sprintf (tmp_str, "rr%ld(r%ld)", instr_data->arg_reg[datum_value],
 561                      instr_data->arg_reg[ARG_RX]);
 562           else
 563             sprintf (tmp_str, "r%ld(r%ld)", instr_data->arg_reg[datum_value],
 564                      instr_data->arg_reg[ARG_RX]);
 565           strcat (out_str, tmp_str);
 566           break;
 567         case CLASS_DISP:
 568           sprintf (tmp_str, "0x%0lx", instr_data->displacement);
 569           strcat (out_str, tmp_str);
 570           break;
 571         case CLASS_IMM:
 572           if (datum_value == ARG_IMM2)  /* True with EI/DI instructions only.  */
 573             {
 574               print_intr (tmp_str, instr_data->interrupts);
 575               strcat (out_str, tmp_str);
 576               break;
 577             }
 578           sprintf (tmp_str, "#0x%0lx", instr_data->immediate);
 579           strcat (out_str, tmp_str);
 580           break;
 581         case CLASS_CC:
 582           sprintf (tmp_str, "%s", codes[instr_data->cond_code]);
 583           strcat (out_str, tmp_str);
 584           break;
 585         case CLASS_CTRL:
 586           sprintf (tmp_str, "%s", ctrl_names[instr_data->ctrl_code]);
 587           strcat (out_str, tmp_str);
 588           break;
 589         case CLASS_DA:
 590         case CLASS_ADDRESS:
 591           sprintf (tmp_str, "0x%0lx", instr_data->address);
 592           strcat (out_str, tmp_str);
 593           break;
 594         case CLASS_IR:
 595           if (is_segmented)
 596             sprintf (tmp_str, "@rr%ld", instr_data->arg_reg[datum_value]);
 597           else
 598             sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
 599           strcat (out_str, tmp_str);
 600           break;
 601         case CLASS_IRO:
 602           sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
 603           strcat (out_str, tmp_str);
 604           break;
 605         case CLASS_FLAGS:
 606           print_flags(tmp_str, instr_data->flags);
 607           strcat (out_str, tmp_str);
 608           break;
 609         case CLASS_REG_BYTE:
 610           if (instr_data->arg_reg[datum_value] >= 0x8)
 611             sprintf (tmp_str, "rl%ld",
 612                      instr_data->arg_reg[datum_value] - 0x8);
 613           else
 614             sprintf (tmp_str, "rh%ld", instr_data->arg_reg[datum_value]);
 615           strcat (out_str, tmp_str);
 616           break;
 617         case CLASS_REG_WORD:
 618           sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
 619           strcat (out_str, tmp_str);
 620           break;
 621         case CLASS_REG_QUAD:
 622           sprintf (tmp_str, "rq%ld", instr_data->arg_reg[datum_value]);
 623           strcat (out_str, tmp_str);
 624           break;
 625         case CLASS_REG_LONG:
 626           sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
 627           strcat (out_str, tmp_str);
 628           break;
 629         case CLASS_PR:
 630           if (is_segmented)
 631             sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
 632           else
 633             sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
 634           strcat (out_str, tmp_str);
 635           break;
 636         default:
 637           abort ();
 638           break;
 639         }
 640     }
 641
 642   strcpy (instr_data->instr_asmsrc, out_str);
 643 }