1/* Disassemble z8000 code.
2   Copyright (C) 1992-2022 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#include "libiberty.h"
24
25#define DEFINE_TABLE
26#include "z8k-opc.h"
27
28#include <setjmp.h>
29
30typedef struct
31{
32  /* These are all indexed by nibble number (i.e only every other entry
33     of bytes is used, and every 4th entry of words).  */
34  unsigned char nibbles[24];
35  unsigned char bytes[24];
36  unsigned short words[24];
37
38  /* Nibble number of first word not yet fetched.  */
39  unsigned int max_fetched;
40  bfd_vma insn_start;
41  OPCODES_SIGJMP_BUF bailout;
42
43  int tabl_index;
44  char instr_asmsrc[80];
45  unsigned long arg_reg[0x0f];
46  unsigned long immediate;
47  unsigned long displacement;
48  unsigned long address;
49  unsigned long cond_code;
50  unsigned long ctrl_code;
51  unsigned long flags;
52  unsigned long interrupts;
53}
54instr_data_s;
55
56/* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive)
57   to ADDR (exclusive) are valid.  Returns 1 for success, longjmps
58   on error.  */
59#define FETCH_DATA(info, nibble) \
60  ((nibble) < ((instr_data_s *) (info->private_data))->max_fetched \
61   ? 1 : fetch_data ((info), (nibble)))
62
63static int
64fetch_data (struct disassemble_info *info, int nibble)
65{
66  unsigned char mybuf[20];
67  int status;
68  instr_data_s *priv = (instr_data_s *) info->private_data;
69
70  if ((nibble % 4) != 0)
71    abort ();
72
73  status = (*info->read_memory_func) (priv->insn_start,
74				      (bfd_byte *) mybuf,
75				      nibble / 2,
76				      info);
77  if (status != 0)
78    {
79      (*info->memory_error_func) (status, priv->insn_start, info);
80      OPCODES_SIGLONGJMP (priv->bailout, 1);
81    }
82
83  {
84    int i;
85    unsigned char *p = mybuf;
86
87    for (i = 0; i < nibble;)
88      {
89	priv->words[i] = (p[0] << 8) | p[1];
90
91	priv->bytes[i] = *p;
92	priv->nibbles[i++] = *p >> 4;
93	priv->nibbles[i++] = *p & 0xf;
94
95	++p;
96	priv->bytes[i] = *p;
97	priv->nibbles[i++] = *p >> 4;
98	priv->nibbles[i++] = *p & 0xf;
99
100	++p;
101      }
102  }
103  priv->max_fetched = nibble;
104  return 1;
105}
106
107static char *codes[16] =
108  {
109    "f",
110    "lt",
111    "le",
112    "ule",
113    "ov/pe",
114    "mi",
115    "eq",
116    "c/ult",
117    "t",
118    "ge",
119    "gt",
120    "ugt",
121    "nov/po",
122    "pl",
123    "ne",
124    "nc/uge"
125  };
126
127static char *ctrl_names[8] =
128  {
129    "<invld>",
130    "flags",
131    "fcw",
132    "refresh",
133    "psapseg",
134    "psapoff",
135    "nspseg",
136    "nspoff"
137  };
138
139static int seg_length;
140int z8k_lookup_instr (unsigned char *, disassemble_info *);
141static void output_instr (instr_data_s *, unsigned long, disassemble_info *);
142static void unpack_instr (instr_data_s *, int, disassemble_info *);
143static void unparse_instr (instr_data_s *, int);
144
145static int
146print_insn_z8k (bfd_vma addr, disassemble_info *info, int is_segmented)
147{
148  instr_data_s instr_data;
149
150  info->private_data = &instr_data;
151  instr_data.max_fetched = 0;
152  instr_data.insn_start = addr;
153  if (OPCODES_SIGSETJMP (instr_data.bailout) != 0)
154    /* Error return.  */
155    return -1;
156
157  info->bytes_per_chunk = 2;
158  info->bytes_per_line = 6;
159  info->display_endian = BFD_ENDIAN_BIG;
160
161  instr_data.tabl_index = z8k_lookup_instr (instr_data.nibbles, info);
162  if (instr_data.tabl_index >= 0)
163    {
164      unpack_instr (&instr_data, is_segmented, info);
165      unparse_instr (&instr_data, is_segmented);
166      output_instr (&instr_data, addr, info);
167      return z8k_table[instr_data.tabl_index].length + seg_length;
168    }
169  else
170    {
171      FETCH_DATA (info, 4);
172      (*info->fprintf_func) (info->stream, ".word %02x%02x",
173			     instr_data.bytes[0], instr_data.bytes[2]);
174      return 2;
175    }
176}
177
178int
179print_insn_z8001 (bfd_vma addr, disassemble_info *info)
180{
181  return print_insn_z8k (addr, info, 1);
182}
183
184int
185print_insn_z8002 (bfd_vma addr, disassemble_info *info)
186{
187  return print_insn_z8k (addr, info, 0);
188}
189
190int
191z8k_lookup_instr (unsigned char *nibbles, disassemble_info *info)
192{
193  unsigned int nibl_index, tabl_index;
194  int nibl_matched;
195  int need_fetch = 0;
196  unsigned short instr_nibl;
197  unsigned short tabl_datum, datum_class, datum_value;
198
199  nibl_matched = 0;
200  tabl_index = 0;
201  FETCH_DATA (info, 4);
202  while (!nibl_matched && z8k_table[tabl_index].name)
203    {
204      nibl_matched = 1;
205      for (nibl_index = 0;
206	   nibl_matched
207	     && nibl_index < ARRAY_SIZE (z8k_table[0].byte_info)
208	     && nibl_index < z8k_table[tabl_index].length * 2;
209	   nibl_index++)
210	{
211	  if ((nibl_index % 4) == 0)
212            {
213              /* Fetch data only if it isn't already there.  */
214              if (nibl_index >= 4 || (nibl_index < 4 && need_fetch))
215                FETCH_DATA (info, nibl_index + 4);   /* Fetch one word at a time.  */
216              if (nibl_index < 4)
217                need_fetch = 0;
218              else
219                need_fetch = 1;
220            }
221	  instr_nibl = nibbles[nibl_index];
222
223	  tabl_datum = z8k_table[tabl_index].byte_info[nibl_index];
224	  datum_class = tabl_datum & CLASS_MASK;
225	  datum_value = ~CLASS_MASK & tabl_datum;
226
227	  switch (datum_class)
228	    {
229	    case CLASS_BIT:
230	      if (datum_value != instr_nibl)
231		nibl_matched = 0;
232	      break;
233	    case CLASS_IGNORE:
234	      break;
235	    case CLASS_00II:
236	      if (!((~instr_nibl) & 0x4))
237		nibl_matched = 0;
238	      break;
239	    case CLASS_01II:
240	      if (!(instr_nibl & 0x4))
241		nibl_matched = 0;
242	      break;
243	    case CLASS_0CCC:
244	      if (!((~instr_nibl) & 0x8))
245		nibl_matched = 0;
246	      break;
247	    case CLASS_1CCC:
248	      if (!(instr_nibl & 0x8))
249		nibl_matched = 0;
250	      break;
251	    case CLASS_0DISP7:
252	      if (!((~instr_nibl) & 0x8))
253		nibl_matched = 0;
254	      nibl_index += 1;
255	      break;
256	    case CLASS_1DISP7:
257	      if (!(instr_nibl & 0x8))
258		nibl_matched = 0;
259	      nibl_index += 1;
260	      break;
261	    case CLASS_REGN0:
262	      if (instr_nibl == 0)
263		nibl_matched = 0;
264	      break;
265	    case CLASS_BIT_1OR2:
266	      if ((instr_nibl | 0x2) != (datum_value | 0x2))
267		nibl_matched = 0;
268	      break;
269	    default:
270	      break;
271	    }
272	}
273
274      if (nibl_matched)
275	return tabl_index;
276
277      tabl_index++;
278    }
279  return -1;
280}
281
282static void
283output_instr (instr_data_s *instr_data,
284              unsigned long addr ATTRIBUTE_UNUSED,
285              disassemble_info *info)
286{
287  unsigned int num_bytes;
288  char out_str[100];
289
290  out_str[0] = 0;
291
292  num_bytes = (z8k_table[instr_data->tabl_index].length + seg_length) * 2;
293  FETCH_DATA (info, num_bytes);
294
295  strcat (out_str, instr_data->instr_asmsrc);
296
297  (*info->fprintf_func) (info->stream, "%s", out_str);
298}
299
300static void
301unpack_instr (instr_data_s *instr_data, int is_segmented, disassemble_info *info)
302{
303  unsigned int nibl_count, loop;
304  unsigned short instr_nibl, instr_byte, instr_word;
305  long instr_long;
306  unsigned int tabl_datum, datum_class;
307  unsigned short datum_value;
308
309  nibl_count = 0;
310  loop = 0;
311  seg_length = 0;
312
313  while (z8k_table[instr_data->tabl_index].byte_info[loop] != 0)
314    {
315      FETCH_DATA (info, nibl_count + 4 - (nibl_count % 4));
316      instr_nibl = instr_data->nibbles[nibl_count];
317      instr_byte = instr_data->bytes[nibl_count & ~1];
318      instr_word = instr_data->words[nibl_count & ~3];
319
320      tabl_datum = z8k_table[instr_data->tabl_index].byte_info[loop];
321      datum_class = tabl_datum & CLASS_MASK;
322      datum_value = tabl_datum & ~CLASS_MASK;
323
324      switch (datum_class)
325	{
326	case CLASS_DISP:
327	  switch (datum_value)
328	    {
329	    case ARG_DISP16:
330	      instr_data->displacement = instr_data->insn_start + 4
331		+ (signed short) (instr_word & 0xffff);
332	      nibl_count += 3;
333	      break;
334	    case ARG_DISP12:
335	      if (instr_word & 0x800)
336		/* Negative 12 bit displacement.  */
337		instr_data->displacement = instr_data->insn_start + 2
338		  - (signed short) ((instr_word & 0xfff) | 0xf000) * 2;
339	      else
340		instr_data->displacement = instr_data->insn_start + 2
341		  - (instr_word & 0x0fff) * 2;
342
343	      nibl_count += 2;
344	      break;
345	    default:
346	      break;
347	    }
348	  break;
349	case CLASS_IMM:
350	  switch (datum_value)
351	    {
352	    case ARG_IMM4:
353	      instr_data->immediate = instr_nibl;
354	      break;
355	    case ARG_NIM4:
356	      instr_data->immediate = (- instr_nibl) & 0xf;
357	      break;
358	    case ARG_NIM8:
359	      instr_data->immediate = (- instr_byte) & 0xff;
360	      nibl_count += 1;
361	      break;
362	    case ARG_IMM8:
363	      instr_data->immediate = instr_byte;
364	      nibl_count += 1;
365	      break;
366	    case ARG_IMM16:
367	      instr_data->immediate = instr_word;
368	      nibl_count += 3;
369	      break;
370	    case ARG_IMM32:
371	      FETCH_DATA (info, nibl_count + 8);
372	      instr_long = ((unsigned) instr_data->words[nibl_count] << 16
373			    | instr_data->words[nibl_count + 4]);
374	      instr_data->immediate = instr_long;
375	      nibl_count += 7;
376	      break;
377	    case ARG_IMMN:
378	      instr_data->immediate = instr_nibl - 1;
379	      break;
380	    case ARG_IMM4M1:
381	      instr_data->immediate = instr_nibl + 1;
382	      break;
383	    case ARG_IMM_1:
384	      instr_data->immediate = 1;
385	      break;
386	    case ARG_IMM_2:
387	      instr_data->immediate = 2;
388	      break;
389	    case ARG_IMM2:
390	      instr_data->immediate = instr_nibl & 0x3;
391	      break;
392	    default:
393	      break;
394	    }
395	  break;
396	case CLASS_CC:
397	  instr_data->cond_code = instr_nibl;
398	  break;
399	case CLASS_ADDRESS:
400	  if (is_segmented)
401	    {
402	      if (instr_nibl & 0x8)
403		{
404		  FETCH_DATA (info, nibl_count + 8);
405		  instr_long = ((unsigned) instr_data->words[nibl_count] << 16
406				| instr_data->words[nibl_count + 4]);
407		  instr_data->address = ((instr_word & 0x7f00) << 16
408					 | (instr_long & 0xffff));
409		  nibl_count += 7;
410		  seg_length = 2;
411		}
412	      else
413		{
414		  instr_data->address = ((instr_word & 0x7f00) << 16
415					 | (instr_word & 0x00ff));
416		  nibl_count += 3;
417		}
418	    }
419	  else
420	    {
421	      instr_data->address = instr_word;
422	      nibl_count += 3;
423	    }
424	  break;
425	case CLASS_0CCC:
426	case CLASS_1CCC:
427	  instr_data->ctrl_code = instr_nibl & 0x7;
428	  break;
429	case CLASS_0DISP7:
430	  instr_data->displacement =
431	    instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
432	  nibl_count += 1;
433	  break;
434	case CLASS_1DISP7:
435	  instr_data->displacement =
436	    instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
437	  nibl_count += 1;
438	  break;
439	case CLASS_01II:
440	  instr_data->interrupts = instr_nibl & 0x3;
441	  break;
442	case CLASS_00II:
443	  instr_data->interrupts = instr_nibl & 0x3;
444	  break;
445	case CLASS_IGNORE:
446	case CLASS_BIT:
447	  instr_data->ctrl_code = instr_nibl & 0x7;
448	  break;
449	case CLASS_FLAGS:
450	  instr_data->flags = instr_nibl;
451	  break;
452	case CLASS_REG:
453	  instr_data->arg_reg[datum_value] = instr_nibl;
454	  break;
455	case CLASS_REGN0:
456	  instr_data->arg_reg[datum_value] = instr_nibl;
457	  break;
458	case CLASS_DISP8:
459	  instr_data->displacement =
460	    instr_data->insn_start + 2 + (signed char) instr_byte * 2;
461	  nibl_count += 1;
462	  break;
463        case CLASS_BIT_1OR2:
464          instr_data->immediate = ((instr_nibl >> 1) & 0x1) + 1;
465          nibl_count += 1;
466	  break;
467	default:
468	  abort ();
469	  break;
470	}
471
472      loop += 1;
473      nibl_count += 1;
474    }
475}
476
477static void
478print_intr(char *tmp_str, unsigned long interrupts)
479{
480  int comma = 0;
481
482  *tmp_str = 0;
483  if (! (interrupts & 2))
484    {
485      strcat (tmp_str, "vi");
486      comma = 1;
487    }
488  if (! (interrupts & 1))
489    {
490      if (comma) strcat (tmp_str, ",");
491      strcat (tmp_str, "nvi");
492    }
493}
494
495static void
496print_flags(char *tmp_str, unsigned long flags)
497{
498  int comma = 0;
499
500  *tmp_str = 0;
501  if (flags & 8)
502    {
503      strcat (tmp_str, "c");
504      comma = 1;
505    }
506  if (flags & 4)
507    {
508      if (comma) strcat (tmp_str, ",");
509      strcat (tmp_str, "z");
510      comma = 1;
511    }
512  if (flags & 2)
513    {
514      if (comma) strcat (tmp_str, ",");
515      strcat (tmp_str, "s");
516      comma = 1;
517    }
518  if (flags & 1)
519    {
520      if (comma) strcat (tmp_str, ",");
521      strcat (tmp_str, "p");
522    }
523}
524
525static void
526unparse_instr (instr_data_s *instr_data, int is_segmented)
527{
528  unsigned short datum_value;
529  unsigned int tabl_datum, datum_class;
530  int loop, loop_limit;
531  char out_str[80], tmp_str[25];
532
533  sprintf (out_str, "%s\t", z8k_table[instr_data->tabl_index].name);
534
535  loop_limit = z8k_table[instr_data->tabl_index].noperands;
536  for (loop = 0; loop < loop_limit; loop++)
537    {
538      if (loop)
539	strcat (out_str, ",");
540
541      tabl_datum = z8k_table[instr_data->tabl_index].arg_info[loop];
542      datum_class = tabl_datum & CLASS_MASK;
543      datum_value = tabl_datum & ~CLASS_MASK;
544
545      switch (datum_class)
546	{
547	case CLASS_X:
548          sprintf (tmp_str, "0x%0lx(r%ld)", instr_data->address,
549                   instr_data->arg_reg[datum_value]);
550	  strcat (out_str, tmp_str);
551	  break;
552	case CLASS_BA:
553          if (is_segmented)
554            sprintf (tmp_str, "rr%ld(#0x%lx)", instr_data->arg_reg[datum_value],
555                     instr_data->immediate);
556          else
557            sprintf (tmp_str, "r%ld(#0x%lx)", instr_data->arg_reg[datum_value],
558                     instr_data->immediate);
559	  strcat (out_str, tmp_str);
560	  break;
561	case CLASS_BX:
562          if (is_segmented)
563            sprintf (tmp_str, "rr%ld(r%ld)", instr_data->arg_reg[datum_value],
564                     instr_data->arg_reg[ARG_RX]);
565          else
566            sprintf (tmp_str, "r%ld(r%ld)", instr_data->arg_reg[datum_value],
567                     instr_data->arg_reg[ARG_RX]);
568	  strcat (out_str, tmp_str);
569	  break;
570	case CLASS_DISP:
571	  sprintf (tmp_str, "0x%0lx", instr_data->displacement);
572	  strcat (out_str, tmp_str);
573	  break;
574	case CLASS_IMM:
575	  if (datum_value == ARG_IMM2)	/* True with EI/DI instructions only.  */
576	    {
577	      print_intr (tmp_str, instr_data->interrupts);
578	      strcat (out_str, tmp_str);
579	      break;
580	    }
581	  sprintf (tmp_str, "#0x%0lx", instr_data->immediate);
582	  strcat (out_str, tmp_str);
583	  break;
584	case CLASS_CC:
585	  sprintf (tmp_str, "%s", codes[instr_data->cond_code]);
586	  strcat (out_str, tmp_str);
587	  break;
588	case CLASS_CTRL:
589	  sprintf (tmp_str, "%s", ctrl_names[instr_data->ctrl_code]);
590	  strcat (out_str, tmp_str);
591	  break;
592	case CLASS_DA:
593	case CLASS_ADDRESS:
594	  sprintf (tmp_str, "0x%0lx", instr_data->address);
595	  strcat (out_str, tmp_str);
596	  break;
597	case CLASS_IR:
598	  if (is_segmented)
599	    sprintf (tmp_str, "@rr%ld", instr_data->arg_reg[datum_value]);
600	  else
601	    sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
602	  strcat (out_str, tmp_str);
603	  break;
604	case CLASS_IRO:
605          sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
606	  strcat (out_str, tmp_str);
607	  break;
608	case CLASS_FLAGS:
609	  print_flags(tmp_str, instr_data->flags);
610	  strcat (out_str, tmp_str);
611	  break;
612	case CLASS_REG_BYTE:
613	  if (instr_data->arg_reg[datum_value] >= 0x8)
614	    sprintf (tmp_str, "rl%ld",
615		     instr_data->arg_reg[datum_value] - 0x8);
616	  else
617	    sprintf (tmp_str, "rh%ld", instr_data->arg_reg[datum_value]);
618	  strcat (out_str, tmp_str);
619	  break;
620	case CLASS_REG_WORD:
621	  sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
622	  strcat (out_str, tmp_str);
623	  break;
624	case CLASS_REG_QUAD:
625	  sprintf (tmp_str, "rq%ld", instr_data->arg_reg[datum_value]);
626	  strcat (out_str, tmp_str);
627	  break;
628	case CLASS_REG_LONG:
629	  sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
630	  strcat (out_str, tmp_str);
631	  break;
632	case CLASS_PR:
633	  if (is_segmented)
634	    sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
635	  else
636	    sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
637	  strcat (out_str, tmp_str);
638	  break;
639	default:
640	  abort ();
641	  break;
642	}
643    }
644
645  strcpy (instr_data->instr_asmsrc, out_str);
646}
647