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 #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 avr_operand PARAMS ((unsigned int, unsigned int,
  46                                 unsigned int, int, char *, char *, int));
  47
  48 static int
  49 avr_operand (insn, insn2, pc, constraint, buf, comment, regs)
  50      unsigned int insn;
  51      unsigned int insn2;
  52      unsigned int pc;
  53      int constraint;
  54      char *buf;
  55      char *comment;
  56      int regs;
  57 {
  58   int ok = 1;
  59
  60   switch (constraint)
  61     {
  62       /* Any register operand.  */
  63     case 'r':
  64       if (regs)
  65         insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* source register */
  66       else
  67         insn = (insn & 0x01f0) >> 4; /* destination register */
  68
  69       sprintf (buf, "r%d", insn);
  70       break;
  71
  72     case 'd':
  73       if (regs)
  74         sprintf (buf, "r%d", 16 + (insn & 0xf));
  75       else
  76         sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
  77       break;
  78
  79     case 'w':
  80       sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
  81       break;
  82
  83     case 'a':
  84       if (regs)
  85         sprintf (buf, "r%d", 16 + (insn & 7));
  86       else
  87         sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
  88       break;
  89
  90     case 'v':
  91       if (regs)
  92         sprintf (buf, "r%d", (insn & 0xf) * 2);
  93       else
  94         sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
  95       break;
  96
  97     case 'e':
  98       {
  99         char *xyz;
 100
 101         switch (insn & 0x100f)
 102           {
 103             case 0x0000: xyz = "Z";  break;
 104             case 0x1001: xyz = "Z+"; break;
 105             case 0x1002: xyz = "-Z"; break;
 106             case 0x0008: xyz = "Y";  break;
 107             case 0x1009: xyz = "Y+"; break;
 108             case 0x100a: xyz = "-Y"; break;
 109             case 0x100c: xyz = "X";  break;
 110             case 0x100d: xyz = "X+"; break;
 111             case 0x100e: xyz = "-X"; break;
 112             default: xyz = "??"; ok = 0;
 113           }
 114         sprintf (buf, xyz);
 115
 116         if (AVR_UNDEF_P (insn))
 117           sprintf (comment, _("undefined"));
 118       }
 119       break;
 120
 121     case 'z':
 122       *buf++ = 'Z';
 123       if (insn & 0x1)
 124         *buf++ = '+';
 125       *buf = '\0';
 126       if (AVR_UNDEF_P (insn))
 127         sprintf (comment, _("undefined"));
 128       break;
 129
 130     case 'b':
 131       {
 132         unsigned int x;
 133
 134         x = (insn & 7);
 135         x |= (insn >> 7) & (3 << 3);
 136         x |= (insn >> 8) & (1 << 5);
 137
 138         if (insn & 0x8)
 139           *buf++ = 'Y';
 140         else
 141           *buf++ = 'Z';
 142         sprintf (buf, "+%d", x);
 143         sprintf (comment, "0x%02x", x);
 144       }
 145       break;
 146
 147     case 'h':
 148       sprintf (buf, "0x%x",
 149                ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2);
 150       break;
 151
 152     case 'L':
 153       {
 154         int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
 155         sprintf (buf, ".%+-8d", rel_addr);
 156         sprintf (comment, "0x%x", pc + 2 + rel_addr);
 157       }
 158       break;
 159
 160     case 'l':
 161       {
 162         int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
 163         sprintf (buf, ".%+-8d", rel_addr);
 164         sprintf (comment, "0x%x", pc + 2 + rel_addr);
 165       }
 166       break;
 167
 168     case 'i':
 169       sprintf (buf, "0x%04X", insn2);
 170       break;
 171
 172     case 'M':
 173       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 174       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 175       break;
 176
 177     case 'n':
 178       sprintf (buf, "??");
 179       fprintf (stderr, _("Internal disassembler error"));
 180       ok = 0;
 181       break;
 182
 183     case 'K':
 184       {
 185         unsigned int x;
 186
 187         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 188         sprintf (buf, "0x%02x", x);
 189         sprintf (comment, "%d", x);
 190       }
 191       break;
 192
 193     case 's':
 194       sprintf (buf, "%d", insn & 7);
 195       break;
 196
 197     case 'S':
 198       sprintf (buf, "%d", (insn >> 4) & 7);
 199       break;
 200
 201     case 'P':
 202       {
 203         unsigned int x;
 204         x = (insn & 0xf);
 205         x |= (insn >> 5) & 0x30;
 206         sprintf (buf, "0x%02x", x);
 207         sprintf (comment, "%d", x);
 208       }
 209       break;
 210
 211     case 'p':
 212       {
 213         unsigned int x;
 214
 215         x = (insn >> 3) & 0x1f;
 216         sprintf (buf, "0x%02x", x);
 217         sprintf (comment, "%d", x);
 218       }
 219       break;
 220
 221     case '?':
 222       *buf = '\0';
 223       break;
 224
 225     default:
 226       sprintf (buf, "??");
 227       fprintf (stderr, _("unknown constraint `%c'"), constraint);
 228       ok = 0;
 229     }
 230
 231     return ok;
 232 }
 233
 234 static unsigned short avrdis_opcode PARAMS ((bfd_vma, disassemble_info *));
 235
 236 static unsigned short
 237 avrdis_opcode (addr, info)
 238      bfd_vma addr;
 239      disassemble_info *info;
 240 {
 241   bfd_byte buffer[2];
 242   int status;
 243   status = info->read_memory_func(addr, buffer, 2, info);
 244   if (status != 0)
 245     {
 246       info->memory_error_func(status, addr, info);
 247       return -1;
 248     }
 249   return bfd_getl16 (buffer);
 250 }
 251
 252
 253 int
 254 print_insn_avr(addr, info)
 255      bfd_vma addr;
 256      disassemble_info *info;
 257 {
 258   unsigned int insn, insn2;
 259   const struct avr_opcodes_s *opcode;
 260   static unsigned int *maskptr;
 261   void *stream = info->stream;
 262   fprintf_ftype prin = info->fprintf_func;
 263   static unsigned int *avr_bin_masks;
 264   static int initialized;
 265   int cmd_len = 2;
 266   int ok = 0;
 267   char op1[20], op2[20], comment1[40], comment2[40];
 268
 269   if (!initialized)
 270     {
 271       unsigned int nopcodes;
 272
 273       nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
 274
 275       avr_bin_masks = (unsigned int *)
 276         xmalloc (nopcodes * sizeof (unsigned int));
 277
 278       for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 279            opcode->name;
 280            opcode++, maskptr++)
 281         {
 282           char * s;
 283           unsigned int bin = 0;
 284           unsigned int mask = 0;
 285
 286           for (s = opcode->opcode; *s; ++s)
 287             {
 288               bin <<= 1;
 289               mask <<= 1;
 290               bin |= (*s == '1');
 291               mask |= (*s == '1' || *s == '0');
 292             }
 293           assert (s - opcode->opcode == 16);
 294           assert (opcode->bin_opcode == bin);
 295           *maskptr = mask;
 296         }
 297
 298       initialized = 1;
 299     }
 300
 301   insn = avrdis_opcode (addr, info);
 302
 303   for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 304        opcode->name;
 305        opcode++, maskptr++)
 306     {
 307       if ((insn & *maskptr) == opcode->bin_opcode)
 308         break;
 309     }
 310
 311   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 312      `std b+0,r' as `st b,r' (next entry in the table).  */
 313
 314   if (AVR_DISP0_P (insn))
 315     opcode++;
 316
 317   op1[0] = 0;
 318   op2[0] = 0;
 319   comment1[0] = 0;
 320   comment2[0] = 0;
 321
 322   if (opcode->name)
 323     {
 324       char *op = opcode->constraints;
 325
 326       insn2 = 0;
 327       ok = 1;
 328
 329       if (opcode->insn_size > 1)
 330         {
 331           insn2 = avrdis_opcode (addr + 2, info);
 332           cmd_len = 4;
 333         }
 334
 335       if (*op && *op != '?')
 336         {
 337           int regs = REGISTER_P (*op);
 338
 339           ok = avr_operand (insn, insn2, addr, *op, op1, comment1, 0);
 340
 341           if (ok && *(++op) == ',')
 342             ok = avr_operand (insn, insn2, addr, *(++op), op2,
 343                               *comment1 ? comment2 : comment1, regs);
 344         }
 345     }
 346
 347   if (!ok)
 348     {
 349       /* Unknown opcode, or invalid combination of operands.  */
 350       sprintf (op1, "0x%04x", insn);
 351       op2[0] = 0;
 352       sprintf (comment1, "????");
 353       comment2[0] = 0;
 354     }
 355
 356   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 357
 358   if (*op1)
 359     (*prin) (stream, "\t%s", op1);
 360
 361   if (*op2)
 362     (*prin) (stream, ", %s", op2);
 363
 364   if (*comment1)
 365     (*prin) (stream, "\t; %s", comment1);
 366
 367   if (*comment2)
 368     (*prin) (stream, " %s", comment2);
 369
 370   return cmd_len;
 371 }