opcodes/z80-dis.c

   1 /* Print Z80 and R800 instructions
   2    Copyright 2005, 2007 Free Software Foundation, Inc.
   3    Contributed by Arnold Metselaar <arnold_m@operamail.com>
   4
   5    This file is part of the GNU opcodes library.
   6
   7    This library is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    It is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #include "sysdep.h"
  23 #include "dis-asm.h"
  24 #include <stdio.h>
  25
  26 struct buffer
  27 {
  28   bfd_vma base;
  29   int n_fetch;
  30   int n_used;
  31   signed char data[4];
  32 } ;
  33
  34 typedef int (*func)(struct buffer *, disassemble_info *, char *);
  35
  36 struct tab_elt
  37 {
  38   unsigned char val;
  39   unsigned char mask;
  40   func          fp;
  41   char *        text;
  42 } ;
  43
  44 #define TXTSIZ 24
  45 /* Names of 16-bit registers.  */
  46 static char * rr_str[] = { "bc", "de", "hl", "sp" };
  47 /* Names of 8-bit registers.  */
  48 static char * r_str[]  = { "b", "c", "d", "e", "h", "l", "(hl)", "a" };
  49 /* Texts for condition codes.  */
  50 static char * cc_str[] = { "nz", "z", "nc", "c", "po", "pe", "p", "m" };
  51 /* Instruction names for 8-bit arithmetic, operand "a" is often implicit */
  52 static char * arit_str[] =
  53 {
  54   "add a,", "adc a,", "sub ", "sbc a,", "and ", "xor ", "or ", "cp "
  55 } ;
  56 \f
  57 static int
  58 fetch_data (struct buffer *buf, disassemble_info * info, int n)
  59 {
  60   int r;
  61
  62   if (buf->n_fetch + n > 4)
  63     abort ();
  64
  65   r = info->read_memory_func (buf->base + buf->n_fetch,
  66                               (unsigned char*) buf->data + buf->n_fetch,
  67                               n, info);
  68   if (r == 0)
  69     buf->n_fetch += n;
  70   return !r;
  71 }
  72
  73 static int
  74 prt (struct buffer *buf, disassemble_info * info, char *txt)
  75 {
  76   info->fprintf_func (info->stream, "%s", txt);
  77   buf->n_used = buf->n_fetch;
  78   return 1;
  79 }
  80
  81 static int
  82 prt_e (struct buffer *buf, disassemble_info * info, char *txt)
  83 {
  84   char e;
  85   int target_addr;
  86
  87   if (fetch_data (buf, info, 1))
  88     {
  89       e = buf->data[1];
  90       target_addr = (buf->base + 2 + e) & 0xffff;
  91       buf->n_used = buf->n_fetch;
  92       info->fprintf_func (info->stream, "%s0x%04x", txt, target_addr);
  93     }
  94   else
  95     buf->n_used = -1;
  96
  97   return buf->n_used;
  98 }
  99
 100 static int
 101 jr_cc (struct buffer *buf, disassemble_info * info, char *txt)
 102 {
 103   char mytxt[TXTSIZ];
 104
 105   snprintf (mytxt, TXTSIZ, txt, cc_str[(buf->data[0] >> 3) & 3]);
 106   return prt_e (buf, info, mytxt);
 107 }
 108
 109 static int
 110 prt_nn (struct buffer *buf, disassemble_info * info, char *txt)
 111 {
 112   int nn;
 113   unsigned char *p;
 114
 115   p = (unsigned char*) buf->data + buf->n_fetch;
 116   if (fetch_data (buf, info, 2))
 117     {
 118       nn = p[0] + (p[1] << 8);
 119       info->fprintf_func (info->stream, txt, nn);
 120       buf->n_used = buf->n_fetch;
 121     }
 122   else
 123     buf->n_used = -1;
 124   return buf->n_used;
 125 }
 126
 127 static int
 128 prt_rr_nn (struct buffer *buf, disassemble_info * info, char *txt)
 129 {
 130   char mytxt[TXTSIZ];
 131   int rr;
 132
 133   rr = (buf->data[buf->n_fetch - 1] >> 4) & 3;
 134   snprintf (mytxt, TXTSIZ, txt, rr_str[rr]);
 135   return prt_nn (buf, info, mytxt);
 136 }
 137
 138 static int
 139 prt_rr (struct buffer *buf, disassemble_info * info, char *txt)
 140 {
 141   info->fprintf_func (info->stream, "%s%s", txt,
 142                       rr_str[(buf->data[buf->n_fetch - 1] >> 4) & 3]);
 143   buf->n_used = buf->n_fetch;
 144   return buf->n_used;
 145 }
 146
 147 static int
 148 prt_n (struct buffer *buf, disassemble_info * info, char *txt)
 149 {
 150   int n;
 151   unsigned char *p;
 152
 153   p = (unsigned char*) buf->data + buf->n_fetch;
 154
 155   if (fetch_data (buf, info, 1))
 156     {
 157       n = p[0];
 158       info->fprintf_func (info->stream, txt, n);
 159       buf->n_used = buf->n_fetch;
 160     }
 161   else
 162     buf->n_used = -1;
 163
 164   return buf->n_used;
 165 }
 166
 167 static int
 168 ld_r_n (struct buffer *buf, disassemble_info * info, char *txt)
 169 {
 170   char mytxt[TXTSIZ];
 171
 172   snprintf (mytxt, TXTSIZ, txt, r_str[(buf->data[0] >> 3) & 7]);
 173   return prt_n (buf, info, mytxt);
 174 }
 175
 176 static int
 177 prt_r (struct buffer *buf, disassemble_info * info, char *txt)
 178 {
 179   info->fprintf_func (info->stream, txt,
 180                       r_str[(buf->data[buf->n_fetch - 1] >> 3) & 7]);
 181   buf->n_used = buf->n_fetch;
 182   return buf->n_used;
 183 }
 184
 185 static int
 186 ld_r_r (struct buffer *buf, disassemble_info * info, char *txt)
 187 {
 188   info->fprintf_func (info->stream, txt,
 189                       r_str[(buf->data[buf->n_fetch - 1] >> 3) & 7],
 190                       r_str[buf->data[buf->n_fetch - 1] & 7]);
 191   buf->n_used = buf->n_fetch;
 192   return buf->n_used;
 193 }
 194
 195 static int
 196 arit_r (struct buffer *buf, disassemble_info * info, char *txt)
 197 {
 198   info->fprintf_func (info->stream, txt,
 199                       arit_str[(buf->data[buf->n_fetch - 1] >> 3) & 7],
 200                       r_str[buf->data[buf->n_fetch - 1] & 7]);
 201   buf->n_used = buf->n_fetch;
 202   return buf->n_used;
 203 }
 204
 205 static int
 206 prt_cc (struct buffer *buf, disassemble_info * info, char *txt)
 207 {
 208   info->fprintf_func (info->stream, "%s%s", txt,
 209                       cc_str[(buf->data[0] >> 3) & 7]);
 210   buf->n_used = buf->n_fetch;
 211   return buf->n_used;
 212 }
 213
 214 static int
 215 pop_rr (struct buffer *buf, disassemble_info * info, char *txt)
 216 {
 217   static char *rr_stack[] = { "bc","de","hl","af"};
 218
 219   info->fprintf_func (info->stream, "%s %s", txt,
 220                       rr_stack[(buf->data[0] >> 4) & 3]);
 221   buf->n_used = buf->n_fetch;
 222   return buf->n_used;
 223 }
 224
 225
 226 static int
 227 jp_cc_nn (struct buffer *buf, disassemble_info * info, char *txt)
 228 {
 229   char mytxt[TXTSIZ];
 230
 231   snprintf (mytxt,TXTSIZ,
 232             "%s%s,0x%%04x", txt, cc_str[(buf->data[0] >> 3) & 7]);
 233   return prt_nn (buf, info, mytxt);
 234 }
 235
 236 static int
 237 arit_n (struct buffer *buf, disassemble_info * info, char *txt)
 238 {
 239   char mytxt[TXTSIZ];
 240
 241   snprintf (mytxt,TXTSIZ, txt, arit_str[(buf->data[0] >> 3) & 7]);
 242   return prt_n (buf, info, mytxt);
 243 }
 244
 245 static int
 246 rst (struct buffer *buf, disassemble_info * info, char *txt)
 247 {
 248   info->fprintf_func (info->stream, txt, buf->data[0] & 0x38);
 249   buf->n_used = buf->n_fetch;
 250   return buf->n_used;
 251 }
 252
 253 \f
 254 static int
 255 cis (struct buffer *buf, disassemble_info * info, char *txt ATTRIBUTE_UNUSED)
 256 {
 257   static char * opar[] = { "ld", "cp", "in", "out" };
 258   char * op;
 259   char c;
 260
 261   c = buf->data[1];
 262   op = ((0x13 & c) == 0x13) ? "ot" : (opar[c & 3]);
 263   info->fprintf_func (info->stream,
 264                       "%s%c%s", op,
 265                       (c & 0x08) ? 'd' : 'i',
 266                       (c & 0x10) ? "r" : "");
 267   buf->n_used = 2;
 268   return buf->n_used;
 269 }
 270
 271 static int
 272 dump (struct buffer *buf, disassemble_info * info, char *txt)
 273 {
 274   int i;
 275
 276   info->fprintf_func (info->stream, "defb ");
 277   for (i = 0; txt[i]; ++i)
 278     info->fprintf_func (info->stream, i ? ", 0x%02x" : "0x%02x",
 279                         (unsigned char) buf->data[i]);
 280   buf->n_used = i;
 281   return buf->n_used;
 282 }
 283 \f
 284 /* Table to disassemble machine codes with prefix 0xED.  */
 285 struct tab_elt opc_ed[] =
 286 {
 287   { 0x70, 0xFF, prt, "in f,(c)" },
 288   { 0x70, 0xFF, dump, "xx" },
 289   { 0x40, 0xC7, prt_r, "in %s,(c)" },
 290   { 0x71, 0xFF, prt, "out (c),0" },
 291   { 0x70, 0xFF, dump, "xx" },
 292   { 0x41, 0xC7, prt_r, "out (c),%s" },
 293   { 0x42, 0xCF, prt_rr, "sbc hl," },
 294   { 0x43, 0xCF, prt_rr_nn, "ld (0x%%04x),%s" },
 295   { 0x44, 0xFF, prt, "neg" },
 296   { 0x45, 0xFF, prt, "retn" },
 297   { 0x46, 0xFF, prt, "im 0" },
 298   { 0x47, 0xFF, prt, "ld i,a" },
 299   { 0x4A, 0xCF, prt_rr, "adc hl," },
 300   { 0x4B, 0xCF, prt_rr_nn, "ld %s,(0x%%04x)" },
 301   { 0x4D, 0xFF, prt, "reti" },
 302   { 0x4F, 0xFF, prt, "ld r,a" },
 303   { 0x56, 0xFF, prt, "im 1" },
 304   { 0x57, 0xFF, prt, "ld a,i" },
 305   { 0x5E, 0xFF, prt, "im 2" },
 306   { 0x5F, 0xFF, prt, "ld a,r" },
 307   { 0x67, 0xFF, prt, "rrd" },
 308   { 0x6F, 0xFF, prt, "rld" },
 309   { 0xA0, 0xE4, cis, "" },
 310   { 0xC3, 0xFF, prt, "muluw hl,bc" },
 311   { 0xC5, 0xE7, prt_r, "mulub a,%s" },
 312   { 0xF3, 0xFF, prt, "muluw hl,sp" },
 313   { 0x00, 0x00, dump, "xx" }
 314 };
 315
 316 static int
 317 pref_ed (struct buffer * buf, disassemble_info * info,
 318          char* txt ATTRIBUTE_UNUSED)
 319 {
 320   struct tab_elt *p;
 321
 322   if (fetch_data(buf, info, 1))
 323     {
 324       for (p = opc_ed; p->val != (buf->data[1] & p->mask); ++p)
 325         ;
 326       p->fp (buf, info, p->text);
 327     }
 328   else
 329     buf->n_used = -1;
 330
 331   return buf->n_used;
 332 }
 333 \f
 334 /* Instruction names for the instructions addressing single bits.  */
 335 static char *cb1_str[] = { "", "bit", "res", "set"};
 336 /* Instruction names for shifts and rotates.  */
 337 static char *cb2_str[] =
 338 {
 339   "rlc", "rrc", "rl", "rr", "sla", "sra", "sli", "srl"
 340 };
 341
 342 static int
 343 pref_cb (struct buffer * buf, disassemble_info * info,
 344          char* txt ATTRIBUTE_UNUSED)
 345 {
 346   if (fetch_data (buf, info, 1))
 347     {
 348       buf->n_used = 2;
 349       if ((buf->data[1] & 0xc0) == 0)
 350         info->fprintf_func (info->stream, "%s %s",
 351                             cb2_str[(buf->data[1] >> 3) & 7],
 352                             r_str[buf->data[1] & 7]);
 353       else
 354         info->fprintf_func (info->stream, "%s %d,%s",
 355                             cb1_str[(buf->data[1] >> 6) & 3],
 356                             (buf->data[1] >> 3) & 7,
 357                             r_str[buf->data[1] & 7]);
 358     }
 359   else
 360     buf->n_used = -1;
 361
 362   return buf->n_used;
 363 }
 364 \f
 365 static int
 366 addvv (struct buffer * buf, disassemble_info * info, char* txt)
 367 {
 368   info->fprintf_func (info->stream, "add %s,%s", txt, txt);
 369
 370   return buf->n_used = buf->n_fetch;
 371 }
 372
 373 static int
 374 ld_v_v (struct buffer * buf, disassemble_info * info, char* txt)
 375 {
 376   char mytxt[TXTSIZ];
 377
 378   snprintf (mytxt, TXTSIZ, "ld %s%%s,%s%%s", txt, txt);
 379   return ld_r_r (buf, info, mytxt);
 380 }
 381
 382 static int
 383 prt_d (struct buffer *buf, disassemble_info * info, char *txt)
 384 {
 385   int d;
 386   signed char *p;
 387
 388   p = buf->data + buf->n_fetch;
 389
 390   if (fetch_data (buf, info, 1))
 391     {
 392       d = p[0];
 393       info->fprintf_func (info->stream, txt, d);
 394       buf->n_used = buf->n_fetch;
 395     }
 396   else
 397     buf->n_used = -1;
 398
 399   return buf->n_used;
 400 }
 401
 402 static int
 403 prt_d_n (struct buffer *buf, disassemble_info * info, char *txt)
 404 {
 405   char mytxt[TXTSIZ];
 406   int d;
 407   signed char *p;
 408
 409   p = buf->data + buf->n_fetch;
 410
 411   if (fetch_data (buf, info, 1))
 412     {
 413       d = p[0];
 414       snprintf (mytxt, TXTSIZ, txt, d);
 415       return prt_n (buf, info, mytxt);
 416     }
 417   else
 418     buf->n_used = -1;
 419
 420   return buf->n_used;
 421 }
 422
 423 static int
 424 arit_d (struct buffer *buf, disassemble_info * info, char *txt)
 425 {
 426   char mytxt[TXTSIZ];
 427   signed char c;
 428
 429   c = buf->data[buf->n_fetch - 1];
 430   snprintf (mytxt, TXTSIZ, txt, arit_str[(c >> 3) & 7]);
 431   return prt_d (buf, info, mytxt);
 432 }
 433
 434 static int
 435 ld_r_d (struct buffer *buf, disassemble_info * info, char *txt)
 436 {
 437   char mytxt[TXTSIZ];
 438   signed char c;
 439
 440   c = buf->data[buf->n_fetch - 1];
 441   snprintf (mytxt, TXTSIZ, txt, r_str[(c >> 3) & 7]);
 442   return prt_d (buf, info, mytxt);
 443 }
 444
 445 static int
 446 ld_d_r(struct buffer *buf, disassemble_info * info, char *txt)
 447 {
 448   char mytxt[TXTSIZ];
 449   signed char c;
 450
 451   c = buf->data[buf->n_fetch - 1];
 452   snprintf (mytxt, TXTSIZ, txt, r_str[c & 7]);
 453   return prt_d (buf, info, mytxt);
 454 }
 455
 456 static int
 457 pref_xd_cb (struct buffer * buf, disassemble_info * info, char* txt)
 458 {
 459   if (fetch_data (buf, info, 2))
 460     {
 461       int d;
 462       char arg[TXTSIZ];
 463       signed char *p;
 464
 465       buf->n_used = 4;
 466       p = buf->data;
 467       d = p[2];
 468
 469       if (((p[3] & 0xC0) == 0x40) || ((p[3] & 7) == 0x06))
 470         snprintf (arg, TXTSIZ, "(%s%+d)", txt, d);
 471       else
 472         snprintf (arg, TXTSIZ, "(%s%+d),%s", txt, d, r_str[p[3] & 7]);
 473
 474       if ((p[3] & 0xc0) == 0)
 475         info->fprintf_func (info->stream, "%s %s",
 476                             cb2_str[(buf->data[3] >> 3) & 7],
 477                             arg);
 478       else
 479         info->fprintf_func (info->stream, "%s %d,%s",
 480                             cb1_str[(buf->data[3] >> 6) & 3],
 481                             (buf->data[3] >> 3) & 7,
 482                             arg);
 483     }
 484   else
 485     buf->n_used = -1;
 486
 487   return buf->n_used;
 488 }
 489 \f
 490 /* Table to disassemble machine codes with prefix 0xDD or 0xFD.  */
 491 static struct tab_elt opc_ind[] =
 492 {
 493   { 0x24, 0xF7, prt_r, "inc %s%%s" },
 494   { 0x25, 0xF7, prt_r, "dec %s%%s" },
 495   { 0x26, 0xF7, ld_r_n, "ld %s%%s,0x%%%%02x" },
 496   { 0x21, 0xFF, prt_nn, "ld %s,0x%%04x" },
 497   { 0x22, 0xFF, prt_nn, "ld (0x%%04x),%s" },
 498   { 0x2A, 0xFF, prt_nn, "ld %s,(0x%%04x)" },
 499   { 0x23, 0xFF, prt, "inc %s" },
 500   { 0x2B, 0xFF, prt, "dec %s" },
 501   { 0x29, 0xFF, addvv, "%s" },
 502   { 0x09, 0xCF, prt_rr, "add %s," },
 503   { 0x34, 0xFF, prt_d, "inc (%s%%+d)" },
 504   { 0x35, 0xFF, prt_d, "dec (%s%%+d)" },
 505   { 0x36, 0xFF, prt_d_n, "ld (%s%%+d),0x%%%%02x" },
 506
 507   { 0x76, 0xFF, dump, "h" },
 508   { 0x46, 0xC7, ld_r_d, "ld %%s,(%s%%%%+d)" },
 509   { 0x70, 0xF8, ld_d_r, "ld (%s%%%%+d),%%s" },
 510   { 0x64, 0xF6, ld_v_v, "%s" },
 511   { 0x60, 0xF0, ld_r_r, "ld %s%%s,%%s" },
 512   { 0x44, 0xC6, ld_r_r, "ld %%s,%s%%s" },
 513
 514   { 0x86, 0xC7, arit_d, "%%s(%s%%%%+d)" },
 515   { 0x84, 0xC6, arit_r, "%%s%s%%s" },
 516
 517   { 0xE1, 0xFF, prt, "pop %s" },
 518   { 0xE5, 0xFF, prt, "push %s" },
 519   { 0xCB, 0xFF, pref_xd_cb, "%s" },
 520   { 0xE3, 0xFF, prt, "ex (sp),%s" },
 521   { 0xE9, 0xFF, prt, "jp (%s)" },
 522   { 0xF9, 0xFF, prt, "ld sp,%s" },
 523   { 0x00, 0x00, dump, "?" },
 524 } ;
 525
 526 static int
 527 pref_ind (struct buffer * buf, disassemble_info * info, char* txt)
 528 {
 529   if (fetch_data (buf, info, 1))
 530     {
 531       char mytxt[TXTSIZ];
 532       struct tab_elt *p;
 533
 534       for (p = opc_ind; p->val != (buf->data[1] & p->mask); ++p)
 535         ;
 536       snprintf (mytxt, TXTSIZ, p->text, txt);
 537       p->fp (buf, info, mytxt);
 538     }
 539   else
 540     buf->n_used = -1;
 541
 542   return buf->n_used;
 543 }
 544
 545 /* Table to disassemble machine codes without prefix.  */
 546 static struct tab_elt opc_main[] =
 547 {
 548   { 0x00, 0xFF, prt, "nop" },
 549   { 0x01, 0xCF, prt_rr_nn, "ld %s,0x%%04x" },
 550   { 0x02, 0xFF, prt, "ld (bc),a" },
 551   { 0x03, 0xCF, prt_rr, "inc " },
 552   { 0x04, 0xC7, prt_r, "inc %s" },
 553   { 0x05, 0xC7, prt_r, "dec %s" },
 554   { 0x06, 0xC7, ld_r_n, "ld %s,0x%%02x" },
 555   { 0x07, 0xFF, prt, "rlca" },
 556   { 0x08, 0xFF, prt, "ex af,af'" },
 557   { 0x09, 0xCF, prt_rr, "add hl," },
 558   { 0x0A, 0xFF, prt, "ld a,(bc)" },
 559   { 0x0B, 0xCF, prt_rr, "dec " },
 560   { 0x0F, 0xFF, prt, "rrca" },
 561   { 0x10, 0xFF, prt_e, "djnz " },
 562   { 0x12, 0xFF, prt, "ld (de),a" },
 563   { 0x17, 0xFF, prt, "rla" },
 564   { 0x18, 0xFF, prt_e, "jr "},
 565   { 0x1A, 0xFF, prt, "ld a,(de)" },
 566   { 0x1F, 0xFF, prt, "rra" },
 567   { 0x20, 0xE7, jr_cc, "jr %s,"},
 568   { 0x22, 0xFF, prt_nn, "ld (0x%04x),hl" },
 569   { 0x27, 0xFF, prt, "daa"},
 570   { 0x2A, 0xFF, prt_nn, "ld hl,(0x%04x)" },
 571   { 0x2F, 0xFF, prt, "cpl" },
 572   { 0x32, 0xFF, prt_nn, "ld (0x%04x),a" },
 573   { 0x37, 0xFF, prt, "scf" },
 574   { 0x3A, 0xFF, prt_nn, "ld a,(0x%04x)" },
 575   { 0x3F, 0xFF, prt, "ccf" },
 576
 577   { 0x76, 0xFF, prt, "halt" },
 578   { 0x40, 0xC0, ld_r_r, "ld %s,%s"},
 579
 580   { 0x80, 0xC0, arit_r, "%s%s" },
 581
 582   { 0xC0, 0xC7, prt_cc, "ret " },
 583   { 0xC1, 0xCF, pop_rr, "pop" },
 584   { 0xC2, 0xC7, jp_cc_nn, "jp " },
 585   { 0xC3, 0xFF, prt_nn, "jp 0x%04x" },
 586   { 0xC4, 0xC7, jp_cc_nn, "call " },
 587   { 0xC5, 0xCF, pop_rr, "push" },
 588   { 0xC6, 0xC7, arit_n, "%s0x%%02x" },
 589   { 0xC7, 0xC7, rst, "rst 0x%02x" },
 590   { 0xC9, 0xFF, prt, "ret" },
 591   { 0xCB, 0xFF, pref_cb, "" },
 592   { 0xCD, 0xFF, prt_nn, "call 0x%04x" },
 593   { 0xD3, 0xFF, prt_n, "out (0x%02x),a" },
 594   { 0xD9, 0xFF, prt, "exx" },
 595   { 0xDB, 0xFF, prt_n, "in a,(0x%02x)" },
 596   { 0xDD, 0xFF, pref_ind, "ix" },
 597   { 0xE3, 0xFF, prt, "ex (sp),hl" },
 598   { 0xE9, 0xFF, prt, "jp (hl)" },
 599   { 0xEB, 0xFF, prt, "ex de,hl" },
 600   { 0xED, 0xFF, pref_ed, ""},
 601   { 0xF3, 0xFF, prt, "di" },
 602   { 0xF9, 0xFF, prt, "ld sp,hl" },
 603   { 0xFB, 0xFF, prt, "ei" },
 604   { 0xFD, 0xFF, pref_ind, "iy" },
 605   { 0x00, 0x00, prt, "????" },
 606 } ;
 607
 608 int
 609 print_insn_z80 (bfd_vma addr, disassemble_info * info)
 610 {
 611   struct buffer buf;
 612   struct tab_elt *p;
 613
 614   buf.base = addr;
 615   buf.n_fetch = 0;
 616   buf.n_used = 0;
 617
 618   if (! fetch_data (& buf, info, 1))
 619     return -1;
 620
 621   for (p = opc_main; p->val != (buf.data[0] & p->mask); ++p)
 622     ;
 623   p->fp (& buf, info, p->text);
 624
 625   return buf.n_used;
 626 }