opcodes/avr-dis.c

   1 /* Disassemble AVR instructions.
   2    Copyright (C) 1999-2022 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 "disassemble.h"
  26 #include "opintl.h"
  27 #include "libiberty.h"
  28 #include <stdint.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,
  53              unsigned int        insn2,
  54              unsigned int        pc,
  55              int                 constraint,
  56              char *              opcode_str,
  57              char *              buf,
  58              char *              comment,
  59              int                 regs,
  60              int *               sym,
  61              bfd_vma *           sym_addr,
  62              disassemble_info *  info)
  63 {
  64   int ok = 1;
  65   *sym = 0;
  66
  67   switch (constraint)
  68     {
  69       /* Any register operand.  */
  70     case 'r':
  71       if (regs)
  72         insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* Source register.  */
  73       else
  74         insn = (insn & 0x01f0) >> 4; /* Destination register.  */
  75
  76       sprintf (buf, "r%d", insn);
  77       break;
  78
  79     case 'd':
  80       if (regs)
  81         sprintf (buf, "r%d", 16 + (insn & 0xf));
  82       else
  83         sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
  84       break;
  85
  86     case 'w':
  87       sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
  88       break;
  89
  90     case 'a':
  91       if (regs)
  92         sprintf (buf, "r%d", 16 + (insn & 7));
  93       else
  94         sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
  95       break;
  96
  97     case 'v':
  98       if (regs)
  99         sprintf (buf, "r%d", (insn & 0xf) * 2);
 100       else
 101         sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
 102       break;
 103
 104     case 'e':
 105       {
 106         char *xyz;
 107
 108         switch (insn & 0x100f)
 109           {
 110             case 0x0000: xyz = "Z";  break;
 111             case 0x1001: xyz = "Z+"; break;
 112             case 0x1002: xyz = "-Z"; break;
 113             case 0x0008: xyz = "Y";  break;
 114             case 0x1009: xyz = "Y+"; break;
 115             case 0x100a: xyz = "-Y"; break;
 116             case 0x100c: xyz = "X";  break;
 117             case 0x100d: xyz = "X+"; break;
 118             case 0x100e: xyz = "-X"; break;
 119             default: xyz = "??"; ok = 0;
 120           }
 121         strcpy (buf, xyz);
 122
 123         if (AVR_UNDEF_P (insn))
 124           sprintf (comment, _("undefined"));
 125       }
 126       break;
 127
 128     case 'z':
 129       *buf++ = 'Z';
 130
 131       /* Check for post-increment. */
 132       char *s;
 133       for (s = opcode_str; *s; ++s)
 134         {
 135           if (*s == '+')
 136             {
 137               if (insn & (1 << (15 - (s - opcode_str))))
 138                 *buf++ = '+';
 139               break;
 140             }
 141         }
 142
 143       *buf = '\0';
 144       if (AVR_UNDEF_P (insn))
 145         sprintf (comment, _("undefined"));
 146       break;
 147
 148     case 'b':
 149       {
 150         unsigned int x;
 151
 152         x = (insn & 7);
 153         x |= (insn >> 7) & (3 << 3);
 154         x |= (insn >> 8) & (1 << 5);
 155
 156         if (insn & 0x8)
 157           *buf++ = 'Y';
 158         else
 159           *buf++ = 'Z';
 160         sprintf (buf, "+%d", x);
 161         sprintf (comment, "0x%02x", x);
 162       }
 163       break;
 164
 165     case 'h':
 166       *sym = 1;
 167       *sym_addr = ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2;
 168       /* See PR binutils/2454.  Ideally we would like to display the hex
 169          value of the address only once, but this would mean recoding
 170          objdump_print_address() which would affect many targets.  */
 171       sprintf (buf, "%#lx", (unsigned long) *sym_addr);
 172       strcpy (comment, comment_start);
 173       info->insn_info_valid = 1;
 174       info->insn_type = dis_jsr;
 175       info->target = *sym_addr;
 176       break;
 177
 178     case 'L':
 179       {
 180         int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
 181         sprintf (buf, ".%+-8d", rel_addr);
 182         *sym = 1;
 183         *sym_addr = pc + 2 + rel_addr;
 184         strcpy (comment, comment_start);
 185         info->insn_info_valid = 1;
 186         info->insn_type = dis_branch;
 187         info->target = *sym_addr;
 188       }
 189       break;
 190
 191     case 'l':
 192       {
 193         int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;
 194
 195         sprintf (buf, ".%+-8d", rel_addr);
 196         *sym = 1;
 197         *sym_addr = pc + 2 + rel_addr;
 198         strcpy (comment, comment_start);
 199         info->insn_info_valid = 1;
 200         info->insn_type = dis_condbranch;
 201         info->target = *sym_addr;
 202       }
 203       break;
 204
 205     case 'i':
 206       {
 207         unsigned int val = insn2 | 0x800000;
 208         *sym = 1;
 209         *sym_addr = val;
 210         sprintf (buf, "0x%04X", insn2);
 211         strcpy (comment, comment_start);
 212       }
 213       break;
 214
 215     case 'j':
 216       {
 217         unsigned int val = ((insn & 0xf) | ((insn & 0x600) >> 5)
 218                                          | ((insn & 0x100) >> 2));
 219         if ((insn & 0x100) == 0)
 220           val |= 0x80;
 221         *sym = 1;
 222         *sym_addr = val | 0x800000;
 223         sprintf (buf, "0x%02x", val);
 224         strcpy (comment, comment_start);
 225       }
 226       break;
 227
 228     case 'M':
 229       sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
 230       sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
 231       break;
 232
 233     case 'n':
 234       sprintf (buf, "??");
 235       /* xgettext:c-format */
 236       opcodes_error_handler (_("internal disassembler error"));
 237       ok = 0;
 238       break;
 239
 240     case 'K':
 241       {
 242         unsigned int x;
 243
 244         x = (insn & 0xf) | ((insn >> 2) & 0x30);
 245         sprintf (buf, "0x%02x", x);
 246         sprintf (comment, "%d", x);
 247       }
 248       break;
 249
 250     case 's':
 251       sprintf (buf, "%d", insn & 7);
 252       break;
 253
 254     case 'S':
 255       sprintf (buf, "%d", (insn >> 4) & 7);
 256       break;
 257
 258     case 'P':
 259       {
 260         unsigned int x;
 261
 262         x = (insn & 0xf);
 263         x |= (insn >> 5) & 0x30;
 264         sprintf (buf, "0x%02x", x);
 265         sprintf (comment, "%d", x);
 266       }
 267       break;
 268
 269     case 'p':
 270       {
 271         unsigned int x;
 272
 273         x = (insn >> 3) & 0x1f;
 274         sprintf (buf, "0x%02x", x);
 275         sprintf (comment, "%d", x);
 276       }
 277       break;
 278
 279     case 'E':
 280       sprintf (buf, "%d", (insn >> 4) & 15);
 281       break;
 282
 283     case '?':
 284       *buf = '\0';
 285       break;
 286
 287     default:
 288       sprintf (buf, "??");
 289       /* xgettext:c-format */
 290       opcodes_error_handler (_("unknown constraint `%c'"), constraint);
 291       ok = 0;
 292     }
 293
 294     return ok;
 295 }
 296
 297 /* Read the opcode from ADDR.  Return 0 in success and save opcode
 298    in *INSN, otherwise, return -1.  */
 299
 300 static int
 301 avrdis_opcode (bfd_vma addr, disassemble_info *info, uint16_t *insn)
 302 {
 303   bfd_byte buffer[2];
 304   int status;
 305
 306   status = info->read_memory_func (addr, buffer, 2, info);
 307
 308   if (status == 0)
 309     {
 310       *insn = bfd_getl16 (buffer);
 311       return 0;
 312     }
 313
 314   info->memory_error_func (status, addr, info);
 315   return -1;
 316 }
 317
 318
 319 int
 320 print_insn_avr (bfd_vma addr, disassemble_info *info)
 321 {
 322   uint16_t insn, insn2;
 323   const struct avr_opcodes_s *opcode;
 324   static unsigned int *maskptr;
 325   void *stream = info->stream;
 326   fprintf_ftype prin = info->fprintf_func;
 327   static unsigned int *avr_bin_masks;
 328   static int initialized;
 329   int cmd_len = 2;
 330   int ok = 0;
 331   char op1[20], op2[20], comment1[40], comment2[40];
 332   int sym_op1 = 0, sym_op2 = 0;
 333   bfd_vma sym_addr1, sym_addr2;
 334
 335   /* Clear instruction information field.  */
 336   info->insn_info_valid = 0;
 337   info->branch_delay_insns = 0;
 338   info->data_size = 0;
 339   info->insn_type = dis_noninsn;
 340   info->target = 0;
 341   info->target2 = 0;
 342
 343   if (!initialized)
 344     {
 345       unsigned int nopcodes;
 346
 347       /* PR 4045: Try to avoid duplicating the 0x prefix that
 348          objdump_print_addr() will put on addresses when there
 349          is no symbol table available.  */
 350       if (info->symtab_size == 0)
 351         comment_start = " ";
 352
 353       nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);
 354
 355       avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));
 356
 357       for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 358            opcode->name;
 359            opcode++, maskptr++)
 360         {
 361           char * s;
 362           unsigned int bin = 0;
 363           unsigned int mask = 0;
 364
 365           for (s = opcode->opcode; *s; ++s)
 366             {
 367               bin <<= 1;
 368               mask <<= 1;
 369               bin |= (*s == '1');
 370               mask |= (*s == '1' || *s == '0');
 371             }
 372           assert (s - opcode->opcode == 16);
 373           assert (opcode->bin_opcode == bin);
 374           *maskptr = mask;
 375         }
 376
 377       initialized = 1;
 378     }
 379
 380   if (avrdis_opcode (addr, info, &insn)  != 0)
 381     return -1;
 382
 383   for (opcode = avr_opcodes, maskptr = avr_bin_masks;
 384        opcode->name;
 385        opcode++, maskptr++)
 386     {
 387       if ((opcode->isa == AVR_ISA_TINY) && (info->mach != bfd_mach_avrtiny))
 388         continue;
 389       if ((insn & *maskptr) == opcode->bin_opcode)
 390         break;
 391     }
 392
 393   /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
 394      `std b+0,r' as `st b,r' (next entry in the table).  */
 395
 396   if (AVR_DISP0_P (insn))
 397     opcode++;
 398
 399   op1[0] = 0;
 400   op2[0] = 0;
 401   comment1[0] = 0;
 402   comment2[0] = 0;
 403
 404   if (opcode->name)
 405     {
 406       char *constraints = opcode->constraints;
 407       char *opcode_str = opcode->opcode;
 408
 409       insn2 = 0;
 410       ok = 1;
 411
 412       if (opcode->insn_size > 1)
 413         {
 414           if (avrdis_opcode (addr + 2, info, &insn2) != 0)
 415             return -1;
 416           cmd_len = 4;
 417         }
 418
 419       if (*constraints && *constraints != '?')
 420         {
 421           int regs = REGISTER_P (*constraints);
 422
 423           ok = avr_operand (insn, insn2, addr, *constraints, opcode_str, op1,
 424                             comment1, 0, &sym_op1, &sym_addr1, info);
 425
 426           if (ok && *(++constraints) == ',')
 427             ok = avr_operand (insn, insn2, addr, *(++constraints), opcode_str,
 428                               op2, *comment1 ? comment2 : comment1, regs,
 429                               &sym_op2, &sym_addr2, info);
 430         }
 431     }
 432
 433   if (!ok)
 434     {
 435       /* Unknown opcode, or invalid combination of operands.  */
 436       sprintf (op1, "0x%04x", insn);
 437       op2[0] = 0;
 438       sprintf (comment1, "????");
 439       comment2[0] = 0;
 440     }
 441
 442   (*prin) (stream, "%s", ok ? opcode->name : ".word");
 443
 444   if (*op1)
 445       (*prin) (stream, "\t%s", op1);
 446
 447   if (*op2)
 448     (*prin) (stream, ", %s", op2);
 449
 450   if (*comment1)
 451     (*prin) (stream, "\t; %s", comment1);
 452
 453   if (sym_op1)
 454     info->print_address_func (sym_addr1, info);
 455
 456   if (*comment2)
 457     (*prin) (stream, " %s", comment2);
 458
 459   if (sym_op2)
 460     info->print_address_func (sym_addr2, info);
 461
 462   return cmd_len;
 463 }