opcodes/avr-dis.c

   1 /* Disassemble AVR instructions.
   2    Copyright 1999, 2000, 2002, 2004, 2005, 2006, 2007, 2008
   3    Free Software Foundation, Inc.
   4
   5    Contributed by Denis Chertykov <denisc@overta.ru>
   6
   7    This file is part of libopcodes.
   8
   9    This library is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3, or (at your option)
  12    any later version.
  13
  14    It is distributed in the hope that it will be useful, but WITHOUT
  15    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  16    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  17    License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22    MA 02110-1301, USA.  */
  23
  24 #include <assert.h>
  25 #include "sysdep.h"
  26 #include "dis-asm.h"
  27 #include "opintl.h"
  28 #include "libiberty.h"
  29
  30 struct avr_opcodes_s
  31 {
  32   char *name;
  33   char *constraints;
  34   char *opcode;
  35   int insn_size;                /* In words.  */
  36   int isa;
  37   unsigned int bin_opcode;
  38 };
  39
  40 #define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
  41 {#NAME, CONSTR, OPCODE, SIZE, ISA, BIN},
  42
  43 const struct avr_opcodes_s avr_opcodes[] =
  44 {
  45   #include "opcode/avr.h"
  46   {NULL, NULL, NULL, 0, 0, 0}
  47 };
  48
  49 static const char * comment_start = "0x";
  50
  51 static int
  52 avr_operand (unsigned int insn, unsigned int insn2, unsigned int pc, int constraint,
  53              char *buf, char *comment, int regs, int *sym, bfd_vma *sym_addr)
  54 {
  55   int ok = 1;
  56   *sym = 0;
  57
  58   switch (constraint)
  59     {
  60       /* Any register operand.  */
  61     case 'r':
  62       if (regs)
  63         insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* Source register.  */
  64       else
  65         insn = (insn & 0x01f0) >> 4; /* Destination register.  */
  66
  67       sprintf (buf, "r%d", insn);
  68       break;
  69
  70     case 'd':
  71       if (regs)
  72         sprintf (buf, "r%d", 16 + (insn & 0xf));
  73       else
  74         sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
  75       break;
  76
  77     case 'w':
  78       sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
  79       break;
  80
  81     case 'a':
  82       if (regs)
  83         sprintf (buf, "r%d", 16 + (insn & 7));
  84       else
  85         sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
  86       break;
  87
  88     case 'v':
  89       if (regs)
  90         sprintf (buf, "r%d", (insn & 0xf) * 2);
  91       else
  92         sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
  93       break;
  94
  95     case 'e':
  96       {
  97         char *xyz;
  98
  99         switch (insn & 0x100f)
 100           {
 101             case 0x0000: xyz = "Z";  break;
 102             case 0x1001: xyz = "Z+"; break;
 103             case 0x1002: xyz = "-Z"; break;
 104             case 0x0008: xyz = "Y";  break;
 105             case 0x1009: xyz = "Y+"; break;
 106             case 0x100a: xyz = "-Y"; break;
 107             case 0x100c: xyz = "X";  break;
 108             case 0x100d: xyz = "X+"; break;
 109             case 0x100e: xyz = "-X"; break;
 110             default: xyz = "??"; ok = 0;
 111           }
 112         strcpy (buf, xyz);
 113
 114         if (AVR_UNDEF_P (insn))
 115           sprintf (comment, _("undefined"));
 116       }
 117       break;
 118
 119     case 'z':
 120       *buf++ = 'Z';
 121       if (insn & 0x1)
 122         *buf++ = '+';
 123       *buf = '\0';
 124       if (AVR_UNDEF_P (insn))
 125         sprintf (comment, _("undefined"));
 126       break;
 127
 128     case 'b':
 129       {
 130         unsigned int x;
 131
 132         x = (insn & 7);
 133         x |= (insn >> 7) & (3 << 3);
 134         x |= (insn >> 8) & (1 << 5);
 135
 136         if (insn & 0x8)
 137           *buf++ = 'Y';
 138         else
 139           *buf++ = 'Z';
 140         sprintf (buf, "+%d", x);
 141         sprintf (comment, "0x%02x", x);
 142       }
 143       break;
 144
 145     case 'h':
 146       *sym = 1;
 147       *sym_addr = ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2;
 148       /* See PR binutils/2454.  Ideally we would like to display the hex
 149          value of the address only once, but this would mean recoding
 150          objdump_print_address() which would affect many targets.  */
 151       sprintf (buf, "%#lx", (unsigned long) *sym_addr);
 152       strcpy (comment, comment_start);
 153       break;
 154
 155     case 'L':
 156       {
 157         int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
 158         sprintf (buf, ".%+-8d", rel_addr);
 159         *sym = 1;
 160         *sym_addr = pc + 2 + rel_addr;
 161         strcpy (comment, comment_start);
 162       }
 163       break;
 164
 165     case 'l':
 166       {
 167         int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
 168
 169         sprintf (buf, ".%+-8d", rel_addr);
 170         *sym = 1;
 171         *sym_addr = pc + 2 + rel_addr;
 172         strcpy (comment, comment_start);
 173       }
 174       break;
 175
 176     case 'i':
 177       sprintf (buf, "0x%04X", insn2);
 178       break;
 179
 180     case 'M':
 181       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 182       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 183       break;
 184
 185     case 'n':
 186       sprintf (buf, "??");
 187       fprintf (stderr, _("Internal disassembler error"));
 188       ok = 0;
 189       break;
 190
 191     case 'K':
 192       {
 193         unsigned int x;
 194
 195         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 196         sprintf (buf, "0x%02x", x);
 197         sprintf (comment, "%d", x);
 198       }
 199       break;
 200
 201     case 's':
 202       sprintf (buf, "%d", insn & 7);
 203       break;
 204
 205     case 'S':
 206       sprintf (buf, "%d", (insn >> 4) & 7);
 207       break;
 208
 209     case 'P':
 210       {
 211         unsigned int x;
 212
 213         x = (insn & 0xf);
 214         x |= (insn >> 5) & 0x30;
 215         sprintf (buf, "0x%02x", x);
 216         sprintf (comment, "%d", x);
 217       }
 218       break;
 219
 220     case 'p':
 221       {
 222         unsigned int x;
 223
 224         x = (insn >> 3) & 0x1f;
 225         sprintf (buf, "0x%02x", x);
 226         sprintf (comment, "%d", x);
 227       }
 228       break;
 229
 230     case '?':
 231       *buf = '\0';
 232       break;
 233
 234     default:
 235       sprintf (buf, "??");
 236       fprintf (stderr, _("unknown constraint `%c'"), constraint);
 237       ok = 0;
 238     }
 239
 240     return ok;
 241 }
 242
 243 static unsigned short
 244 avrdis_opcode (bfd_vma addr, disassemble_info *info)
 245 {
 246   bfd_byte buffer[2];
 247   int status;
 248
 249   status = info->read_memory_func (addr, buffer, 2, info);
 250
 251   if (status == 0)
 252     return bfd_getl16 (buffer);
 253
 254   info->memory_error_func (status, addr, info);
 255   return -1;
 256 }
 257
 258
 259 int
 260 print_insn_avr (bfd_vma addr, disassemble_info *info)
 261 {
 262   unsigned int insn, insn2;
 263   const struct avr_opcodes_s *opcode;
 264   static unsigned int *maskptr;
 265   void *stream = info->stream;
 266   fprintf_ftype prin = info->fprintf_func;
 267   static unsigned int *avr_bin_masks;
 268   static int initialized;
 269   int cmd_len = 2;
 270   int ok = 0;
 271   char op1[20], op2[20], comment1[40], comment2[40];
 272   int sym_op1 = 0, sym_op2 = 0;
 273   bfd_vma sym_addr1, sym_addr2;
 274
 275
 276   if (!initialized)
 277     {
 278       unsigned int nopcodes;
 279
 280       /* PR 4045: Try to avoid duplicating the 0x prefix that
 281          objdump_print_addr() will put on addresses when there
 282          is no symbol table available.  */
 283       if (info->symtab_size == 0)
 284         comment_start = " ";
 285
 286       nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
 287
 288       avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));
 289
 290       for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 291            opcode->name;
 292            opcode++, maskptr++)
 293         {
 294           char * s;
 295           unsigned int bin = 0;
 296           unsigned int mask = 0;
 297
 298           for (s = opcode->opcode; *s; ++s)
 299             {
 300               bin <<= 1;
 301               mask <<= 1;
 302               bin |= (*s == '1');
 303               mask |= (*s == '1' || *s == '0');
 304             }
 305           assert (s - opcode->opcode == 16);
 306           assert (opcode->bin_opcode == bin);
 307           *maskptr = mask;
 308         }
 309
 310       initialized = 1;
 311     }
 312
 313   insn = avrdis_opcode (addr, info);
 314
 315   for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 316        opcode->name;
 317        opcode++, maskptr++)
 318     if ((insn & *maskptr) == opcode->bin_opcode)
 319       break;
 320
 321   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 322      `std b+0,r' as `st b,r' (next entry in the table).  */
 323
 324   if (AVR_DISP0_P (insn))
 325     opcode++;
 326
 327   op1[0] = 0;
 328   op2[0] = 0;
 329   comment1[0] = 0;
 330   comment2[0] = 0;
 331
 332   if (opcode->name)
 333     {
 334       char *op = opcode->constraints;
 335
 336       insn2 = 0;
 337       ok = 1;
 338
 339       if (opcode->insn_size > 1)
 340         {
 341           insn2 = avrdis_opcode (addr + 2, info);
 342           cmd_len = 4;
 343         }
 344
 345       if (*op && *op != '?')
 346         {
 347           int regs = REGISTER_P (*op);
 348
 349           ok = avr_operand (insn, insn2, addr, *op, op1, comment1, 0, &sym_op1, &sym_addr1);
 350
 351           if (ok && *(++op) == ',')
 352             ok = avr_operand (insn, insn2, addr, *(++op), op2,
 353                               *comment1 ? comment2 : comment1, regs, &sym_op2, &sym_addr2);
 354         }
 355     }
 356
 357   if (!ok)
 358     {
 359       /* Unknown opcode, or invalid combination of operands.  */
 360       sprintf (op1, "0x%04x", insn);
 361       op2[0] = 0;
 362       sprintf (comment1, "????");
 363       comment2[0] = 0;
 364     }
 365
 366   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 367
 368   if (*op1)
 369       (*prin) (stream, "\t%s", op1);
 370
 371   if (*op2)
 372     (*prin) (stream, ", %s", op2);
 373
 374   if (*comment1)
 375     (*prin) (stream, "\t; %s", comment1);
 376
 377   if (sym_op1)
 378     info->print_address_func (sym_addr1, info);
 379
 380   if (*comment2)
 381     (*prin) (stream, " %s", comment2);
 382
 383   if (sym_op2)
 384     info->print_address_func (sym_addr2, info);
 385
 386   return cmd_len;
 387 }