opcodes/avr-dis.c

   1 /* Disassemble AVR instructions.
   2    Copyright (C) 1999-2015 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
  29 struct 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
  42 const struct avr_opcodes_s avr_opcodes[] =
  43 {
  44   #include "opcode/avr.h"
  45   {NULL, NULL, NULL, 0, 0, 0}
  46 };
  47
  48 static const char * comment_start = "0x";
  49
  50 static int
  51 avr_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       sprintf (buf, "0x%04X", insn2);
 188       break;
 189
 190     case 'j':
 191       {
 192         unsigned int val = ((insn & 0xf) | ((insn & 0x600) >> 5)
 193                                          | ((insn & 0x100) >> 2));
 194         if (val > 0 && !(insn & 0x100))
 195           val |= 0x80;
 196         sprintf (buf, "0x%02x", val);
 197         sprintf (buf, "%d", val);
 198       }
 199       break;
 200
 201     case 'M':
 202       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 203       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 204       break;
 205
 206     case 'n':
 207       sprintf (buf, "??");
 208       fprintf (stderr, _("Internal disassembler error"));
 209       ok = 0;
 210       break;
 211
 212     case 'K':
 213       {
 214         unsigned int x;
 215
 216         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 217         sprintf (buf, "0x%02x", x);
 218         sprintf (comment, "%d", x);
 219       }
 220       break;
 221
 222     case 's':
 223       sprintf (buf, "%d", insn & 7);
 224       break;
 225
 226     case 'S':
 227       sprintf (buf, "%d", (insn >> 4) & 7);
 228       break;
 229
 230     case 'P':
 231       {
 232         unsigned int x;
 233
 234         x = (insn & 0xf);
 235         x |= (insn >> 5) & 0x30;
 236         sprintf (buf, "0x%02x", x);
 237         sprintf (comment, "%d", x);
 238       }
 239       break;
 240
 241     case 'p':
 242       {
 243         unsigned int x;
 244
 245         x = (insn >> 3) & 0x1f;
 246         sprintf (buf, "0x%02x", x);
 247         sprintf (comment, "%d", x);
 248       }
 249       break;
 250
 251     case 'E':
 252       sprintf (buf, "%d", (insn >> 4) & 15);
 253       break;
 254
 255     case '?':
 256       *buf = '\0';
 257       break;
 258
 259     default:
 260       sprintf (buf, "??");
 261       fprintf (stderr, _("unknown constraint `%c'"), constraint);
 262       ok = 0;
 263     }
 264
 265     return ok;
 266 }
 267
 268 static unsigned short
 269 avrdis_opcode (bfd_vma addr, disassemble_info *info)
 270 {
 271   bfd_byte buffer[2];
 272   int status;
 273
 274   status = info->read_memory_func (addr, buffer, 2, info);
 275
 276   if (status == 0)
 277     return bfd_getl16 (buffer);
 278
 279   info->memory_error_func (status, addr, info);
 280   return -1;
 281 }
 282
 283
 284 int
 285 print_insn_avr (bfd_vma addr, disassemble_info *info)
 286 {
 287   unsigned int insn, insn2;
 288   const struct avr_opcodes_s *opcode;
 289   static unsigned int *maskptr;
 290   void *stream = info->stream;
 291   fprintf_ftype prin = info->fprintf_func;
 292   static unsigned int *avr_bin_masks;
 293   static int initialized;
 294   int cmd_len = 2;
 295   int ok = 0;
 296   char op1[20], op2[20], comment1[40], comment2[40];
 297   int sym_op1 = 0, sym_op2 = 0;
 298   bfd_vma sym_addr1, sym_addr2;
 299
 300
 301   if (!initialized)
 302     {
 303       unsigned int nopcodes;
 304
 305       /* PR 4045: Try to avoid duplicating the 0x prefix that
 306          objdump_print_addr() will put on addresses when there
 307          is no symbol table available.  */
 308       if (info->symtab_size == 0)
 309         comment_start = " ";
 310
 311       nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
 312
 313       avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));
 314
 315       for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 316            opcode->name;
 317            opcode++, maskptr++)
 318         {
 319           char * s;
 320           unsigned int bin = 0;
 321           unsigned int mask = 0;
 322
 323           for (s = opcode->opcode; *s; ++s)
 324             {
 325               bin <<= 1;
 326               mask <<= 1;
 327               bin |= (*s == '1');
 328               mask |= (*s == '1' || *s == '0');
 329             }
 330           assert (s - opcode->opcode == 16);
 331           assert (opcode->bin_opcode == bin);
 332           *maskptr = mask;
 333         }
 334
 335       initialized = 1;
 336     }
 337
 338   insn = avrdis_opcode (addr, info);
 339
 340   for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 341        opcode->name;
 342        opcode++, maskptr++)
 343     {
 344       if ((opcode->isa == AVR_ISA_TINY) && (info->mach != bfd_mach_avrtiny))
 345         continue;
 346       if ((insn & *maskptr) == opcode->bin_opcode)
 347         break;
 348     }
 349
 350   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 351      `std b+0,r' as `st b,r' (next entry in the table).  */
 352
 353   if (AVR_DISP0_P (insn))
 354     opcode++;
 355
 356   op1[0] = 0;
 357   op2[0] = 0;
 358   comment1[0] = 0;
 359   comment2[0] = 0;
 360
 361   if (opcode->name)
 362     {
 363       char *constraints = opcode->constraints;
 364       char *opcode_str = opcode->opcode;
 365
 366       insn2 = 0;
 367       ok = 1;
 368
 369       if (opcode->insn_size > 1)
 370         {
 371           insn2 = avrdis_opcode (addr + 2, info);
 372           cmd_len = 4;
 373         }
 374
 375       if (*constraints && *constraints != '?')
 376         {
 377           int regs = REGISTER_P (*constraints);
 378
 379           ok = avr_operand (insn, insn2, addr, *constraints, opcode_str, op1, comment1, 0, &sym_op1, &sym_addr1);
 380
 381           if (ok && *(++constraints) == ',')
 382             ok = avr_operand (insn, insn2, addr, *(++constraints), opcode_str, op2,
 383                               *comment1 ? comment2 : comment1, regs, &sym_op2, &sym_addr2);
 384         }
 385     }
 386
 387   if (!ok)
 388     {
 389       /* Unknown opcode, or invalid combination of operands.  */
 390       sprintf (op1, "0x%04x", insn);
 391       op2[0] = 0;
 392       sprintf (comment1, "????");
 393       comment2[0] = 0;
 394     }
 395
 396   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 397
 398   if (*op1)
 399       (*prin) (stream, "\t%s", op1);
 400
 401   if (*op2)
 402     (*prin) (stream, ", %s", op2);
 403
 404   if (*comment1)
 405     (*prin) (stream, "\t; %s", comment1);
 406
 407   if (sym_op1)
 408     info->print_address_func (sym_addr1, info);
 409
 410   if (*comment2)
 411     (*prin) (stream, " %s", comment2);
 412
 413   if (sym_op2)
 414     info->print_address_func (sym_addr2, info);
 415
 416   return cmd_len;
 417 }