opcodes/avr-dis.c

   1 /* Disassemble AVR instructions.
   2    Copyright 1999, 2000, 2002, 2004, 2005 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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  19
  20 #include <assert.h>
  21 #include "sysdep.h"
  22 #include "dis-asm.h"
  23 #include "opintl.h"
  24 #include "libiberty.h"
  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 };
  35
  36 #define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
  37 {#NAME, CONSTR, OPCODE, SIZE, ISA, BIN},
  38
  39 const struct avr_opcodes_s avr_opcodes[] =
  40 {
  41   #include "opcode/avr.h"
  42   {NULL, NULL, NULL, 0, 0, 0}
  43 };
  44
  45 static int
  46 avr_operand (unsigned int insn, unsigned int insn2, unsigned int pc, int constraint,
  47              char *buf, char *comment, int regs, int *sym, bfd_vma *sym_addr)
  48 {
  49   int ok = 1;
  50   *sym = 0;
  51
  52   switch (constraint)
  53     {
  54       /* Any register operand.  */
  55     case 'r':
  56       if (regs)
  57         insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* Source register.  */
  58       else
  59         insn = (insn & 0x01f0) >> 4; /* Destination register.  */
  60
  61       sprintf (buf, "r%d", insn);
  62       break;
  63
  64     case 'd':
  65       if (regs)
  66         sprintf (buf, "r%d", 16 + (insn & 0xf));
  67       else
  68         sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
  69       break;
  70
  71     case 'w':
  72       sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
  73       break;
  74
  75     case 'a':
  76       if (regs)
  77         sprintf (buf, "r%d", 16 + (insn & 7));
  78       else
  79         sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
  80       break;
  81
  82     case 'v':
  83       if (regs)
  84         sprintf (buf, "r%d", (insn & 0xf) * 2);
  85       else
  86         sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
  87       break;
  88
  89     case 'e':
  90       {
  91         char *xyz;
  92
  93         switch (insn & 0x100f)
  94           {
  95             case 0x0000: xyz = "Z";  break;
  96             case 0x1001: xyz = "Z+"; break;
  97             case 0x1002: xyz = "-Z"; break;
  98             case 0x0008: xyz = "Y";  break;
  99             case 0x1009: xyz = "Y+"; break;
 100             case 0x100a: xyz = "-Y"; break;
 101             case 0x100c: xyz = "X";  break;
 102             case 0x100d: xyz = "X+"; break;
 103             case 0x100e: xyz = "-X"; break;
 104             default: xyz = "??"; ok = 0;
 105           }
 106         sprintf (buf, xyz);
 107
 108         if (AVR_UNDEF_P (insn))
 109           sprintf (comment, _("undefined"));
 110       }
 111       break;
 112
 113     case 'z':
 114       *buf++ = 'Z';
 115       if (insn & 0x1)
 116         *buf++ = '+';
 117       *buf = '\0';
 118       if (AVR_UNDEF_P (insn))
 119         sprintf (comment, _("undefined"));
 120       break;
 121
 122     case 'b':
 123       {
 124         unsigned int x;
 125
 126         x = (insn & 7);
 127         x |= (insn >> 7) & (3 << 3);
 128         x |= (insn >> 8) & (1 << 5);
 129
 130         if (insn & 0x8)
 131           *buf++ = 'Y';
 132         else
 133           *buf++ = 'Z';
 134         sprintf (buf, "+%d", x);
 135         sprintf (comment, "0x%02x", x);
 136       }
 137       break;
 138
 139     case 'h':
 140       *sym = 1;
 141       *sym_addr = ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2;
 142       sprintf (buf, "0x");
 143       break;
 144
 145     case 'L':
 146       {
 147         int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
 148         sprintf (buf, ".%+-8d", rel_addr);
 149         *sym = 1;
 150         *sym_addr = pc + 2 + rel_addr;
 151         sprintf (comment, "0x");
 152       }
 153       break;
 154
 155     case 'l':
 156       {
 157         int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
 158         sprintf (buf, ".%+-8d", rel_addr);
 159         *sym = 1;
 160         *sym_addr = pc + 2 + rel_addr;
 161         sprintf (comment, "0x");
 162       }
 163       break;
 164
 165     case 'i':
 166       sprintf (buf, "0x%04X", insn2);
 167       break;
 168
 169     case 'M':
 170       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 171       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 172       break;
 173
 174     case 'n':
 175       sprintf (buf, "??");
 176       fprintf (stderr, _("Internal disassembler error"));
 177       ok = 0;
 178       break;
 179
 180     case 'K':
 181       {
 182         unsigned int x;
 183
 184         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 185         sprintf (buf, "0x%02x", x);
 186         sprintf (comment, "%d", x);
 187       }
 188       break;
 189
 190     case 's':
 191       sprintf (buf, "%d", insn & 7);
 192       break;
 193
 194     case 'S':
 195       sprintf (buf, "%d", (insn >> 4) & 7);
 196       break;
 197
 198     case 'P':
 199       {
 200         unsigned int x;
 201
 202         x = (insn & 0xf);
 203         x |= (insn >> 5) & 0x30;
 204         sprintf (buf, "0x%02x", x);
 205         sprintf (comment, "%d", x);
 206       }
 207       break;
 208
 209     case 'p':
 210       {
 211         unsigned int x;
 212
 213         x = (insn >> 3) & 0x1f;
 214         sprintf (buf, "0x%02x", x);
 215         sprintf (comment, "%d", x);
 216       }
 217       break;
 218
 219     case '?':
 220       *buf = '\0';
 221       break;
 222
 223     default:
 224       sprintf (buf, "??");
 225       fprintf (stderr, _("unknown constraint `%c'"), constraint);
 226       ok = 0;
 227     }
 228
 229     return ok;
 230 }
 231
 232 static unsigned short
 233 avrdis_opcode (bfd_vma addr, disassemble_info *info)
 234 {
 235   bfd_byte buffer[2];
 236   int status;
 237
 238   status = info->read_memory_func (addr, buffer, 2, info);
 239
 240   if (status == 0)
 241     return bfd_getl16 (buffer);
 242
 243   info->memory_error_func (status, addr, info);
 244   return -1;
 245 }
 246
 247
 248 int
 249 print_insn_avr (bfd_vma addr, disassemble_info *info)
 250 {
 251   unsigned int insn, insn2;
 252   const struct avr_opcodes_s *opcode;
 253   static unsigned int *maskptr;
 254   void *stream = info->stream;
 255   fprintf_ftype prin = info->fprintf_func;
 256   static unsigned int *avr_bin_masks;
 257   static int initialized;
 258   int cmd_len = 2;
 259   int ok = 0;
 260   char op1[20], op2[20], comment1[40], comment2[40];
 261   int sym_op1 = 0, sym_op2 = 0;
 262   bfd_vma sym_addr1, sym_addr2;
 263
 264   if (!initialized)
 265     {
 266       unsigned int nopcodes;
 267
 268       nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
 269
 270       avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));
 271
 272       for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 273            opcode->name;
 274            opcode++, maskptr++)
 275         {
 276           char * s;
 277           unsigned int bin = 0;
 278           unsigned int mask = 0;
 279
 280           for (s = opcode->opcode; *s; ++s)
 281             {
 282               bin <<= 1;
 283               mask <<= 1;
 284               bin |= (*s == '1');
 285               mask |= (*s == '1' || *s == '0');
 286             }
 287           assert (s - opcode->opcode == 16);
 288           assert (opcode->bin_opcode == bin);
 289           *maskptr = mask;
 290         }
 291
 292       initialized = 1;
 293     }
 294
 295   insn = avrdis_opcode (addr, info);
 296
 297   for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 298        opcode->name;
 299        opcode++, maskptr++)
 300     if ((insn & *maskptr) == opcode->bin_opcode)
 301       break;
 302
 303   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 304      `std b+0,r' as `st b,r' (next entry in the table).  */
 305
 306   if (AVR_DISP0_P (insn))
 307     opcode++;
 308
 309   op1[0] = 0;
 310   op2[0] = 0;
 311   comment1[0] = 0;
 312   comment2[0] = 0;
 313
 314   if (opcode->name)
 315     {
 316       char *op = opcode->constraints;
 317
 318       insn2 = 0;
 319       ok = 1;
 320
 321       if (opcode->insn_size > 1)
 322         {
 323           insn2 = avrdis_opcode (addr + 2, info);
 324           cmd_len = 4;
 325         }
 326
 327       if (*op && *op != '?')
 328         {
 329           int regs = REGISTER_P (*op);
 330
 331           ok = avr_operand (insn, insn2, addr, *op, op1, comment1, 0, &sym_op1, &sym_addr1);
 332
 333           if (ok && *(++op) == ',')
 334             ok = avr_operand (insn, insn2, addr, *(++op), op2,
 335                               *comment1 ? comment2 : comment1, regs, &sym_op2, &sym_addr2);
 336         }
 337     }
 338
 339   if (!ok)
 340     {
 341       /* Unknown opcode, or invalid combination of operands.  */
 342       sprintf (op1, "0x%04x", insn);
 343       op2[0] = 0;
 344       sprintf (comment1, "????");
 345       comment2[0] = 0;
 346     }
 347
 348   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 349
 350   if (*op1)
 351       (*prin) (stream, "\t%s", op1);
 352
 353   if (*op2)
 354     (*prin) (stream, ", %s", op2);
 355
 356   if (*comment1)
 357     (*prin) (stream, "\t; %s", comment1);
 358
 359   if (sym_op1)
 360     info->print_address_func (sym_addr1, info);
 361
 362   if (*comment2)
 363     (*prin) (stream, " %s", comment2);
 364
 365   if (sym_op2)
 366     info->print_address_func (sym_addr2, info);
 367
 368   return cmd_len;
 369 }