opcodes/avr-dis.c

   1 /* Disassemble AVR instructions.
   2    Copyright 1999, 2000 Free Software Foundation, Inc.
   3
   4    Contributed by Denis Chertykov <denisc@overta.ru>
   5
   6 This program 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 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include <assert.h>
  21 #include "sysdep.h"
  22 #include "dis-asm.h"
  23 #include "opintl.h"
  24
  25
  26 struct avr_opcodes_s
  27 {
  28   char *name;
  29   char *constraints;
  30   char *opcode;
  31   int insn_size;                /* in words */
  32   int isa;
  33   unsigned int bin_opcode;
  34   unsigned int bin_mask;
  35 };
  36
  37 #define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
  38 {#NAME, CONSTR, OPCODE, SIZE, ISA, BIN, 0},
  39
  40 struct avr_opcodes_s avr_opcodes[] =
  41 {
  42   #include "opcode/avr.h"
  43   {NULL, NULL, NULL, 0, 0, 0, 0}
  44 };
  45
  46 static int avr_operand PARAMS ((unsigned int, unsigned int,
  47                                 unsigned int, int, char *, char *, int));
  48
  49 static int
  50 avr_operand (insn, insn2, pc, constraint, buf, comment, regs)
  51      unsigned int insn;
  52      unsigned int insn2;
  53      unsigned int pc;
  54      int constraint;
  55      char *buf;
  56      char *comment;
  57      int regs;
  58 {
  59   int ok = 1;
  60
  61   switch (constraint)
  62     {
  63       /* Any register operand.  */
  64     case 'r':
  65       if (regs)
  66         insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* source register */
  67       else
  68         insn = (insn & 0x01f0) >> 4; /* destination register */
  69
  70       sprintf (buf, "r%d", insn);
  71       break;
  72
  73     case 'd':
  74       if (regs)
  75         sprintf (buf, "r%d", 16 + (insn & 0xf));
  76       else
  77         sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
  78       break;
  79
  80     case 'w':
  81       sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
  82       break;
  83
  84     case 'a':
  85       if (regs)
  86         sprintf (buf, "r%d", 16 + (insn & 7));
  87       else
  88         sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
  89       break;
  90
  91     case 'v':
  92       if (regs)
  93         sprintf (buf, "r%d", (insn & 0xf) * 2);
  94       else
  95         sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
  96       break;
  97
  98     case 'e':
  99       {
 100         char *xyz;
 101
 102         switch (insn & 0x100f)
 103           {
 104             case 0x0000: xyz = "Z";  break;
 105             case 0x1001: xyz = "Z+"; break;
 106             case 0x1002: xyz = "-Z"; break;
 107             case 0x0008: xyz = "Y";  break;
 108             case 0x1009: xyz = "Y+"; break;
 109             case 0x100a: xyz = "-Y"; break;
 110             case 0x100c: xyz = "X";  break;
 111             case 0x100d: xyz = "X+"; break;
 112             case 0x100e: xyz = "-X"; break;
 113             default: xyz = "??"; ok = 0;
 114           }
 115         sprintf (buf, xyz);
 116
 117         if (AVR_UNDEF_P (insn))
 118           sprintf (comment, _("undefined"));
 119       }
 120       break;
 121
 122     case 'z':
 123       *buf++ = 'Z';
 124       if (insn & 0x1)
 125         *buf++ = '+';
 126       *buf = '\0';
 127       if (AVR_UNDEF_P (insn))
 128         sprintf (comment, _("undefined"));
 129       break;
 130
 131     case 'b':
 132       {
 133         unsigned int x;
 134
 135         x = (insn & 7);
 136         x |= (insn >> 7) & (3 << 3);
 137         x |= (insn >> 8) & (1 << 5);
 138
 139         if (insn & 0x8)
 140           *buf++ = 'Y';
 141         else
 142           *buf++ = 'Z';
 143         sprintf (buf, "+%d", x);
 144         sprintf (comment, "0x%02x", x);
 145       }
 146       break;
 147
 148     case 'h':
 149       sprintf (buf, "0x%x",
 150                ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2);
 151       break;
 152
 153     case 'L':
 154       {
 155         int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
 156         sprintf (buf, ".%+-8d", rel_addr);
 157         sprintf (comment, "0x%x", pc + 2 + rel_addr);
 158       }
 159       break;
 160
 161     case 'l':
 162       {
 163         int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
 164         sprintf (buf, ".%+-8d", rel_addr);
 165         sprintf (comment, "0x%x", pc + 2 + rel_addr);
 166       }
 167       break;
 168
 169     case 'i':
 170       sprintf (buf, "0x%04X", insn2);
 171       break;
 172
 173     case 'M':
 174       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 175       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 176       break;
 177
 178     case 'n':
 179       sprintf (buf, "??");
 180       fprintf (stderr, _("Internal disassembler error"));
 181       ok = 0;
 182       break;
 183
 184     case 'K':
 185       {
 186         unsigned int x;
 187
 188         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 189         sprintf (buf, "0x%02x", x);
 190         sprintf (comment, "%d", x);
 191       }
 192       break;
 193
 194     case 's':
 195       sprintf (buf, "%d", insn & 7);
 196       break;
 197
 198     case 'S':
 199       sprintf (buf, "%d", (insn >> 4) & 7);
 200       break;
 201
 202     case 'P':
 203       {
 204         unsigned int x;
 205         x = (insn & 0xf);
 206         x |= (insn >> 5) & 0x30;
 207         sprintf (buf, "0x%02x", x);
 208         sprintf (comment, "%d", x);
 209       }
 210       break;
 211
 212     case 'p':
 213       {
 214         unsigned int x;
 215
 216         x = (insn >> 3) & 0x1f;
 217         sprintf (buf, "0x%02x", x);
 218         sprintf (comment, "%d", x);
 219       }
 220       break;
 221
 222     case '?':
 223       *buf = '\0';
 224       break;
 225
 226     default:
 227       sprintf (buf, "??");
 228       fprintf (stderr, _("unknown constraint `%c'"), constraint);
 229       ok = 0;
 230     }
 231
 232     return ok;
 233 }
 234
 235 static unsigned short avrdis_opcode PARAMS ((bfd_vma, disassemble_info *));
 236
 237 static unsigned short
 238 avrdis_opcode (addr, info)
 239      bfd_vma addr;
 240      disassemble_info *info;
 241 {
 242   bfd_byte buffer[2];
 243   int status;
 244   status = info->read_memory_func(addr, buffer, 2, info);
 245   if (status != 0)
 246     {
 247       info->memory_error_func(status, addr, info);
 248       return -1;
 249     }
 250   return bfd_getl16 (buffer);
 251 }
 252
 253
 254 int
 255 print_insn_avr(addr, info)
 256      bfd_vma addr;
 257      disassemble_info *info;
 258 {
 259   unsigned int insn, insn2;
 260   struct avr_opcodes_s *opcode;
 261   void *stream = info->stream;
 262   fprintf_ftype prin = info->fprintf_func;
 263   static int initialized;
 264   int cmd_len = 2;
 265   int ok = 0;
 266   char op1[20], op2[20], comment1[40], comment2[40];
 267
 268   if (!initialized)
 269     {
 270       initialized = 1;
 271
 272       for (opcode = avr_opcodes; opcode->name; opcode++)
 273         {
 274           char * s;
 275           unsigned int bin = 0;
 276           unsigned int mask = 0;
 277
 278           for (s = opcode->opcode; *s; ++s)
 279             {
 280               bin <<= 1;
 281               mask <<= 1;
 282               bin |= (*s == '1');
 283               mask |= (*s == '1' || *s == '0');
 284             }
 285           assert (s - opcode->opcode == 16);
 286           assert (opcode->bin_opcode == bin);
 287           opcode->bin_mask = mask;
 288         }
 289     }
 290
 291   insn = avrdis_opcode (addr, info);
 292
 293   for (opcode = avr_opcodes; opcode->name; opcode++)
 294     {
 295       if ((insn & opcode->bin_mask) == opcode->bin_opcode)
 296         break;
 297     }
 298
 299   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 300      `std b+0,r' as `st b,r' (next entry in the table).  */
 301
 302   if (AVR_DISP0_P (insn))
 303     opcode++;
 304
 305   op1[0] = 0;
 306   op2[0] = 0;
 307   comment1[0] = 0;
 308   comment2[0] = 0;
 309
 310   if (opcode->name)
 311     {
 312       char *op = opcode->constraints;
 313
 314       insn2 = 0;
 315       ok = 1;
 316
 317       if (opcode->insn_size > 1)
 318         {
 319           insn2 = avrdis_opcode (addr + 2, info);
 320           cmd_len = 4;
 321         }
 322
 323       if (*op && *op != '?')
 324         {
 325           int regs = REGISTER_P (*op);
 326
 327           ok = avr_operand (insn, insn2, addr, *op, op1, comment1, 0);
 328
 329           if (ok && *(++op) == ',')
 330             ok = avr_operand (insn, insn2, addr, *(++op), op2,
 331                               *comment1 ? comment2 : comment1, regs);
 332         }
 333     }
 334
 335   if (!ok)
 336     {
 337       /* Unknown opcode, or invalid combination of operands.  */
 338       sprintf (op1, "0x%04x", insn);
 339       op2[0] = 0;
 340       sprintf (comment1, "????");
 341       comment2[0] = 0;
 342     }
 343
 344   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 345
 346   if (*op1)
 347     (*prin) (stream, "\t%s", op1);
 348
 349   if (*op2)
 350     (*prin) (stream, ", %s", op2);
 351
 352   if (*comment1)
 353     (*prin) (stream, "\t; %s", comment1);
 354
 355   if (*comment2)
 356     (*prin) (stream, " %s", comment2);
 357
 358   return cmd_len;
 359 }