1/* Disassemble AVR instructions.
2   Copyright (C) 1999-2017 Free Software Foundation, Inc.
3
4   Contributed by Denis Chertykov <denisc@overta.ru>
5
6   This file is part of libopcodes.
7
8   This library is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 3, or (at your option)
11   any later version.
12
13   It is distributed in the hope that it will be useful, but WITHOUT
14   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
16   License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with this program; if not, write to the Free Software
20   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21   MA 02110-1301, USA.  */
22
23#include "sysdep.h"
24#include <assert.h>
25#include "dis-asm.h"
26#include "opintl.h"
27#include "libiberty.h"
28
29struct avr_opcodes_s
30{
31  char *name;
32  char *constraints;
33  char *opcode;
34  int insn_size;		/* In words.  */
35  int isa;
36  unsigned int bin_opcode;
37};
38
39#define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
40{#NAME, CONSTR, OPCODE, SIZE, ISA, BIN},
41
42const struct avr_opcodes_s avr_opcodes[] =
43{
44  #include "opcode/avr.h"
45  {NULL, NULL, NULL, 0, 0, 0}
46};
47
48static const char * comment_start = "0x";
49
50static int
51avr_operand (unsigned int insn, unsigned int insn2, unsigned int pc, int constraint,
52             char *opcode_str, char *buf, char *comment, int regs, int *sym, bfd_vma *sym_addr)
53{
54  int ok = 1;
55  *sym = 0;
56
57  switch (constraint)
58    {
59      /* Any register operand.  */
60    case 'r':
61      if (regs)
62	insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* Source register.  */
63      else
64	insn = (insn & 0x01f0) >> 4; /* Destination register.  */
65
66      sprintf (buf, "r%d", insn);
67      break;
68
69    case 'd':
70      if (regs)
71	sprintf (buf, "r%d", 16 + (insn & 0xf));
72      else
73	sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
74      break;
75
76    case 'w':
77      sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
78      break;
79
80    case 'a':
81      if (regs)
82	sprintf (buf, "r%d", 16 + (insn & 7));
83      else
84	sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
85      break;
86
87    case 'v':
88      if (regs)
89	sprintf (buf, "r%d", (insn & 0xf) * 2);
90      else
91	sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
92      break;
93
94    case 'e':
95      {
96	char *xyz;
97
98	switch (insn & 0x100f)
99	  {
100	    case 0x0000: xyz = "Z";  break;
101	    case 0x1001: xyz = "Z+"; break;
102	    case 0x1002: xyz = "-Z"; break;
103	    case 0x0008: xyz = "Y";  break;
104	    case 0x1009: xyz = "Y+"; break;
105	    case 0x100a: xyz = "-Y"; break;
106	    case 0x100c: xyz = "X";  break;
107	    case 0x100d: xyz = "X+"; break;
108	    case 0x100e: xyz = "-X"; break;
109	    default: xyz = "??"; ok = 0;
110	  }
111	strcpy (buf, xyz);
112
113	if (AVR_UNDEF_P (insn))
114	  sprintf (comment, _("undefined"));
115      }
116      break;
117
118    case 'z':
119      *buf++ = 'Z';
120
121      /* Check for post-increment. */
122      char *s;
123      for (s = opcode_str; *s; ++s)
124        {
125          if (*s == '+')
126            {
127	      if (insn & (1 << (15 - (s - opcode_str))))
128		*buf++ = '+';
129              break;
130            }
131        }
132
133      *buf = '\0';
134      if (AVR_UNDEF_P (insn))
135	sprintf (comment, _("undefined"));
136      break;
137
138    case 'b':
139      {
140	unsigned int x;
141
142	x = (insn & 7);
143	x |= (insn >> 7) & (3 << 3);
144	x |= (insn >> 8) & (1 << 5);
145
146	if (insn & 0x8)
147	  *buf++ = 'Y';
148	else
149	  *buf++ = 'Z';
150	sprintf (buf, "+%d", x);
151	sprintf (comment, "0x%02x", x);
152      }
153      break;
154
155    case 'h':
156      *sym = 1;
157      *sym_addr = ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2;
158      /* See PR binutils/2454.  Ideally we would like to display the hex
159	 value of the address only once, but this would mean recoding
160	 objdump_print_address() which would affect many targets.  */
161      sprintf (buf, "%#lx", (unsigned long) *sym_addr);
162      strcpy (comment, comment_start);
163      break;
164
165    case 'L':
166      {
167	int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
168	sprintf (buf, ".%+-8d", rel_addr);
169        *sym = 1;
170        *sym_addr = pc + 2 + rel_addr;
171	strcpy (comment, comment_start);
172      }
173      break;
174
175    case 'l':
176      {
177	int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
178
179	sprintf (buf, ".%+-8d", rel_addr);
180        *sym = 1;
181        *sym_addr = pc + 2 + rel_addr;
182	strcpy (comment, comment_start);
183      }
184      break;
185
186    case 'i':
187      {
188        unsigned int val = insn2 | 0x800000;
189        *sym = 1;
190        *sym_addr = val;
191        sprintf (buf, "0x%04X", insn2);
192        strcpy (comment, comment_start);
193      }
194      break;
195
196    case 'j':
197      {
198        unsigned int val = ((insn & 0xf) | ((insn & 0x600) >> 5)
199                                         | ((insn & 0x100) >> 2));
200        *sym = 1;
201        *sym_addr = val | 0x800000;
202        sprintf (buf, "0x%02x", val);
203        strcpy (comment, comment_start);
204      }
205      break;
206
207    case 'M':
208      sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
209      sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
210      break;
211
212    case 'n':
213      sprintf (buf, "??");
214      fprintf (stderr, _("Internal disassembler error"));
215      ok = 0;
216      break;
217
218    case 'K':
219      {
220	unsigned int x;
221
222	x = (insn & 0xf) | ((insn >> 2) & 0x30);
223	sprintf (buf, "0x%02x", x);
224	sprintf (comment, "%d", x);
225      }
226      break;
227
228    case 's':
229      sprintf (buf, "%d", insn & 7);
230      break;
231
232    case 'S':
233      sprintf (buf, "%d", (insn >> 4) & 7);
234      break;
235
236    case 'P':
237      {
238	unsigned int x;
239
240	x = (insn & 0xf);
241	x |= (insn >> 5) & 0x30;
242	sprintf (buf, "0x%02x", x);
243	sprintf (comment, "%d", x);
244      }
245      break;
246
247    case 'p':
248      {
249	unsigned int x;
250
251	x = (insn >> 3) & 0x1f;
252	sprintf (buf, "0x%02x", x);
253	sprintf (comment, "%d", x);
254      }
255      break;
256
257    case 'E':
258      sprintf (buf, "%d", (insn >> 4) & 15);
259      break;
260
261    case '?':
262      *buf = '\0';
263      break;
264
265    default:
266      sprintf (buf, "??");
267      fprintf (stderr, _("unknown constraint `%c'"), constraint);
268      ok = 0;
269    }
270
271    return ok;
272}
273
274static unsigned short
275avrdis_opcode (bfd_vma addr, disassemble_info *info)
276{
277  bfd_byte buffer[2];
278  int status;
279
280  status = info->read_memory_func (addr, buffer, 2, info);
281
282  if (status == 0)
283    return bfd_getl16 (buffer);
284
285  info->memory_error_func (status, addr, info);
286  return -1;
287}
288
289
290int
291print_insn_avr (bfd_vma addr, disassemble_info *info)
292{
293  unsigned int insn, insn2;
294  const struct avr_opcodes_s *opcode;
295  static unsigned int *maskptr;
296  void *stream = info->stream;
297  fprintf_ftype prin = info->fprintf_func;
298  static unsigned int *avr_bin_masks;
299  static int initialized;
300  int cmd_len = 2;
301  int ok = 0;
302  char op1[20], op2[20], comment1[40], comment2[40];
303  int sym_op1 = 0, sym_op2 = 0;
304  bfd_vma sym_addr1, sym_addr2;
305
306
307  if (!initialized)
308    {
309      unsigned int nopcodes;
310
311      /* PR 4045: Try to avoid duplicating the 0x prefix that
312	 objdump_print_addr() will put on addresses when there
313	 is no symbol table available.  */
314      if (info->symtab_size == 0)
315	comment_start = " ";
316
317      nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
318
319      avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));
320
321      for (opcode = avr_opcodes, maskptr = avr_bin_masks;
322	   opcode->name;
323	   opcode++, maskptr++)
324	{
325	  char * s;
326	  unsigned int bin = 0;
327	  unsigned int mask = 0;
328
329	  for (s = opcode->opcode; *s; ++s)
330	    {
331	      bin <<= 1;
332	      mask <<= 1;
333	      bin |= (*s == '1');
334	      mask |= (*s == '1' || *s == '0');
335	    }
336	  assert (s - opcode->opcode == 16);
337	  assert (opcode->bin_opcode == bin);
338	  *maskptr = mask;
339	}
340
341      initialized = 1;
342    }
343
344  insn = avrdis_opcode (addr, info);
345
346  for (opcode = avr_opcodes, maskptr = avr_bin_masks;
347       opcode->name;
348       opcode++, maskptr++)
349    {
350      if ((opcode->isa == AVR_ISA_TINY) && (info->mach != bfd_mach_avrtiny))
351        continue;
352      if ((insn & *maskptr) == opcode->bin_opcode)
353        break;
354    }
355
356  /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
357     `std b+0,r' as `st b,r' (next entry in the table).  */
358
359  if (AVR_DISP0_P (insn))
360    opcode++;
361
362  op1[0] = 0;
363  op2[0] = 0;
364  comment1[0] = 0;
365  comment2[0] = 0;
366
367  if (opcode->name)
368    {
369      char *constraints = opcode->constraints;
370      char *opcode_str = opcode->opcode;
371
372      insn2 = 0;
373      ok = 1;
374
375      if (opcode->insn_size > 1)
376	{
377	  insn2 = avrdis_opcode (addr + 2, info);
378	  cmd_len = 4;
379	}
380
381      if (*constraints && *constraints != '?')
382	{
383	  int regs = REGISTER_P (*constraints);
384
385	  ok = avr_operand (insn, insn2, addr, *constraints, opcode_str, op1, comment1, 0, &sym_op1, &sym_addr1);
386
387	  if (ok && *(++constraints) == ',')
388	    ok = avr_operand (insn, insn2, addr, *(++constraints), opcode_str, op2,
389			      *comment1 ? comment2 : comment1, regs, &sym_op2, &sym_addr2);
390	}
391    }
392
393  if (!ok)
394    {
395      /* Unknown opcode, or invalid combination of operands.  */
396      sprintf (op1, "0x%04x", insn);
397      op2[0] = 0;
398      sprintf (comment1, "????");
399      comment2[0] = 0;
400    }
401
402  (*prin) (stream, "%s", ok ? opcode->name : ".word");
403
404  if (*op1)
405      (*prin) (stream, "\t%s", op1);
406
407  if (*op2)
408    (*prin) (stream, ", %s", op2);
409
410  if (*comment1)
411    (*prin) (stream, "\t; %s", comment1);
412
413  if (sym_op1)
414    info->print_address_func (sym_addr1, info);
415
416  if (*comment2)
417    (*prin) (stream, " %s", comment2);
418
419  if (sym_op2)
420    info->print_address_func (sym_addr2, info);
421
422  return cmd_len;
423}
424