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