opcodes/msp430-dis.c

   1 /* Disassemble MSP430 instructions.
   2    Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
   3
   4    Contributed by Dmitry Diky <diwil@mail.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,
  19    MA 02110-1301, USA.  */
  20
  21 #include <stdio.h>
  22 #include <ctype.h>
  23 #include <string.h>
  24 #include <sys/types.h>
  25
  26 #include "dis-asm.h"
  27 #include "opintl.h"
  28 #include "libiberty.h"
  29
  30 #define DASM_SECTION
  31 #include "opcode/msp430.h"
  32 #undef DASM_SECTION
  33
  34
  35 #define PS(x)   (0xffff & (x))
  36
  37 static unsigned short
  38 msp430dis_opcode (bfd_vma addr, disassemble_info *info)
  39 {
  40   bfd_byte buffer[2];
  41   int status;
  42
  43   status = info->read_memory_func (addr, buffer, 2, info);
  44   if (status != 0)
  45     {
  46       info->memory_error_func (status, addr, info);
  47       return -1;
  48     }
  49   return bfd_getl16 (buffer);
  50 }
  51
  52 static int
  53 msp430_nooperands (struct msp430_opcode_s *opcode,
  54                    bfd_vma addr ATTRIBUTE_UNUSED,
  55                    unsigned short insn ATTRIBUTE_UNUSED,
  56                    char *comm,
  57                    int *cycles)
  58 {
  59   /* Pop with constant.  */
  60   if (insn == 0x43b2)
  61     return 0;
  62   if (insn == opcode->bin_opcode)
  63     return 2;
  64
  65   if (opcode->fmt == 0)
  66     {
  67       if ((insn & 0x0f00) != 3 || (insn & 0x0f00) != 2)
  68         return 0;
  69
  70       strcpy (comm, "emulated...");
  71       *cycles = 1;
  72     }
  73   else
  74     {
  75       strcpy (comm, "return from interupt");
  76       *cycles = 5;
  77     }
  78
  79   return 2;
  80 }
  81
  82 static int
  83 msp430_singleoperand (disassemble_info *info,
  84                       struct msp430_opcode_s *opcode,
  85                       bfd_vma addr,
  86                       unsigned short insn,
  87                       char *op,
  88                       char *comm,
  89                       int *cycles)
  90 {
  91   int regs = 0, regd = 0;
  92   int ad = 0, as = 0;
  93   int where = 0;
  94   int cmd_len = 2;
  95   short dst = 0;
  96
  97   regd = insn & 0x0f;
  98   regs = (insn & 0x0f00) >> 8;
  99   as = (insn & 0x0030) >> 4;
 100   ad = (insn & 0x0080) >> 7;
 101
 102   switch (opcode->fmt)
 103     {
 104     case 0:                     /* Emulated work with dst register.  */
 105       if (regs != 2 && regs != 3 && regs != 1)
 106         return 0;
 107
 108       /* Check if not clr insn.  */
 109       if (opcode->bin_opcode == 0x4300 && (ad || as))
 110         return 0;
 111
 112       /* Check if really inc, incd insns.  */
 113       if ((opcode->bin_opcode & 0xff00) == 0x5300 && as == 3)
 114         return 0;
 115
 116       if (ad == 0)
 117         {
 118           *cycles = 1;
 119
 120           /* Register.  */
 121           if (regd == 0)
 122             {
 123               *cycles += 1;
 124               sprintf (op, "r0");
 125             }
 126           else if (regd == 1)
 127             sprintf (op, "r1");
 128
 129           else if (regd == 2)
 130             sprintf (op, "r2");
 131
 132           else
 133             sprintf (op, "r%d", regd);
 134         }
 135       else      /* ad == 1 msp430dis_opcode.  */
 136         {
 137           if (regd == 0)
 138             {
 139               /* PC relative.  */
 140               dst = msp430dis_opcode (addr + 2, info);
 141               cmd_len += 2;
 142               *cycles = 4;
 143               sprintf (op, "0x%04x", dst);
 144               sprintf (comm, "PC rel. abs addr 0x%04x",
 145                        PS ((short) (addr + 2) + dst));
 146             }
 147           else if (regd == 2)
 148             {
 149               /* Absolute.  */
 150               dst = msp430dis_opcode (addr + 2, info);
 151               cmd_len += 2;
 152               *cycles = 4;
 153               sprintf (op, "&0x%04x", PS (dst));
 154             }
 155           else
 156             {
 157               dst = msp430dis_opcode (addr + 2, info);
 158               cmd_len += 2;
 159               *cycles = 4;
 160               sprintf (op, "%d(r%d)", dst, regd);
 161             }
 162         }
 163       break;
 164
 165     case 2:     /* rrc, push, call, swpb, rra, sxt, push, call, reti etc...  */
 166       if (as == 0)
 167         {
 168           if (regd == 3)
 169             {
 170               /* Constsnts.  */
 171               sprintf (op, "#0");
 172               sprintf (comm, "r3 As==00");
 173             }
 174           else
 175             {
 176               /* Register.  */
 177               sprintf (op, "r%d", regd);
 178             }
 179           *cycles = 1;
 180         }
 181       else if (as == 2)
 182         {
 183           *cycles = 1;
 184           if (regd == 2)
 185             {
 186               sprintf (op, "#4");
 187               sprintf (comm, "r2 As==10");
 188             }
 189           else if (regd == 3)
 190             {
 191               sprintf (op, "#2");
 192               sprintf (comm, "r3 As==10");
 193             }
 194           else
 195             {
 196               *cycles = 3;
 197               /* Indexed register mode @Rn.  */
 198               sprintf (op, "@r%d", regd);
 199             }
 200         }
 201       else if (as == 3)
 202         {
 203           *cycles = 1;
 204           if (regd == 2)
 205             {
 206               sprintf (op, "#8");
 207               sprintf (comm, "r2 As==11");
 208             }
 209           else if (regd == 3)
 210             {
 211               sprintf (op, "#-1");
 212               sprintf (comm, "r3 As==11");
 213             }
 214           else if (regd == 0)
 215             {
 216               *cycles = 3;
 217               /* absolute. @pc+ */
 218               dst = msp430dis_opcode (addr + 2, info);
 219               cmd_len += 2;
 220               sprintf (op, "#%d", dst);
 221               sprintf (comm, "#0x%04x", PS (dst));
 222             }
 223           else
 224             {
 225               *cycles = 3;
 226               sprintf (op, "@r%d+", regd);
 227             }
 228         }
 229       else if (as == 1)
 230         {
 231           *cycles = 4;
 232           if (regd == 0)
 233             {
 234               /* PC relative.  */
 235               dst = msp430dis_opcode (addr + 2, info);
 236               cmd_len += 2;
 237               sprintf (op, "0x%04x", PS (dst));
 238               sprintf (comm, "PC rel. 0x%04x",
 239                        PS ((short) addr + 2 + dst));
 240             }
 241           else if (regd == 2)
 242             {
 243               /* Absolute.  */
 244               dst = msp430dis_opcode (addr + 2, info);
 245               cmd_len += 2;
 246               sprintf (op, "&0x%04x", PS (dst));
 247             }
 248           else if (regd == 3)
 249             {
 250               *cycles = 1;
 251               sprintf (op, "#1");
 252               sprintf (comm, "r3 As==01");
 253             }
 254           else
 255             {
 256               /* Indexd.  */
 257               dst = msp430dis_opcode (addr + 2, info);
 258               cmd_len += 2;
 259               sprintf (op, "%d(r%d)", dst, regd);
 260             }
 261         }
 262       break;
 263
 264     case 3:                     /* Jumps.  */
 265       where = insn & 0x03ff;
 266       if (where & 0x200)
 267         where |= ~0x03ff;
 268       if (where > 512 || where < -511)
 269         return 0;
 270
 271       where *= 2;
 272       sprintf (op, "$%+-8d", where + 2);
 273       sprintf (comm, "abs 0x%x", PS ((short) (addr) + 2 + where));
 274       *cycles = 2;
 275       return 2;
 276       break;
 277     default:
 278       cmd_len = 0;
 279     }
 280
 281   return cmd_len;
 282 }
 283
 284 static int
 285 msp430_doubleoperand (disassemble_info *info,
 286                       struct msp430_opcode_s *opcode,
 287                       bfd_vma addr,
 288                       unsigned short insn,
 289                       char *op1,
 290                       char *op2,
 291                       char *comm1,
 292                       char *comm2,
 293                       int *cycles)
 294 {
 295   int regs = 0, regd = 0;
 296   int ad = 0, as = 0;
 297   int cmd_len = 2;
 298   short dst = 0;
 299
 300   regd = insn & 0x0f;
 301   regs = (insn & 0x0f00) >> 8;
 302   as = (insn & 0x0030) >> 4;
 303   ad = (insn & 0x0080) >> 7;
 304
 305   if (opcode->fmt == 0)
 306     {
 307       /* Special case: rla and rlc are the only 2 emulated instructions that
 308          fall into two operand instructions.  */
 309       /* With dst, there are only:
 310          Rm             Register,
 311          x(Rm)          Indexed,
 312          0xXXXX         Relative,
 313          &0xXXXX        Absolute
 314          emulated_ins   dst
 315          basic_ins      dst, dst.  */
 316
 317       if (regd != regs || as != ad)
 318         return 0;               /* May be 'data' section.  */
 319
 320       if (ad == 0)
 321         {
 322           /* Register mode.  */
 323           if (regd == 3)
 324             {
 325               strcpy (comm1, _("Illegal as emulation instr"));
 326               return -1;
 327             }
 328
 329           sprintf (op1, "r%d", regd);
 330           *cycles = 1;
 331         }
 332       else                      /* ad == 1 */
 333         {
 334           if (regd == 0)
 335             {
 336               /* PC relative, Symbolic.  */
 337               dst = msp430dis_opcode (addr + 2, info);
 338               cmd_len += 4;
 339               *cycles = 6;
 340               sprintf (op1, "0x%04x", PS (dst));
 341               sprintf (comm1, "PC rel. 0x%04x",
 342                        PS ((short) addr + 2 + dst));
 343
 344             }
 345           else if (regd == 2)
 346             {
 347               /* Absolute.  */
 348               dst = msp430dis_opcode (addr + 2, info);
 349               /* If the 'src' field is not the same as the dst
 350                  then this is not an rla instruction.  */
 351               if (dst != msp430dis_opcode (addr + 4, info))
 352                 return 0;
 353               cmd_len += 4;
 354               *cycles = 6;
 355               sprintf (op1, "&0x%04x", PS (dst));
 356             }
 357           else
 358             {
 359               /* Indexed.  */
 360               dst = msp430dis_opcode (addr + 2, info);
 361               cmd_len += 4;
 362               *cycles = 6;
 363               sprintf (op1, "%d(r%d)", dst, regd);
 364             }
 365         }
 366
 367       *op2 = 0;
 368       *comm2 = 0;
 369       return cmd_len;
 370     }
 371
 372   /* Two operands exactly.  */
 373   if (ad == 0 && regd == 3)
 374     {
 375       /* R2/R3 are illegal as dest: may be data section.  */
 376       strcpy (comm1, _("Illegal as 2-op instr"));
 377       return -1;
 378     }
 379
 380   /* Source.  */
 381   if (as == 0)
 382     {
 383       *cycles = 1;
 384       if (regs == 3)
 385         {
 386           /* Constsnts.  */
 387           sprintf (op1, "#0");
 388           sprintf (comm1, "r3 As==00");
 389         }
 390       else
 391         {
 392           /* Register.  */
 393           sprintf (op1, "r%d", regs);
 394         }
 395     }
 396   else if (as == 2)
 397     {
 398       *cycles = 1;
 399
 400       if (regs == 2)
 401         {
 402           sprintf (op1, "#4");
 403           sprintf (comm1, "r2 As==10");
 404         }
 405       else if (regs == 3)
 406         {
 407           sprintf (op1, "#2");
 408           sprintf (comm1, "r3 As==10");
 409         }
 410       else
 411         {
 412           *cycles = 2;
 413
 414           /* Indexed register mode @Rn.  */
 415           sprintf (op1, "@r%d", regs);
 416         }
 417       if (!regs)
 418         *cycles = 3;
 419     }
 420   else if (as == 3)
 421     {
 422       if (regs == 2)
 423         {
 424           sprintf (op1, "#8");
 425           sprintf (comm1, "r2 As==11");
 426           *cycles = 1;
 427         }
 428       else if (regs == 3)
 429         {
 430           sprintf (op1, "#-1");
 431           sprintf (comm1, "r3 As==11");
 432           *cycles = 1;
 433         }
 434       else if (regs == 0)
 435         {
 436           *cycles = 3;
 437           /* Absolute. @pc+.  */
 438           dst = msp430dis_opcode (addr + 2, info);
 439           cmd_len += 2;
 440           sprintf (op1, "#%d", dst);
 441           sprintf (comm1, "#0x%04x", PS (dst));
 442         }
 443       else
 444         {
 445           *cycles = 2;
 446           sprintf (op1, "@r%d+", regs);
 447         }
 448     }
 449   else if (as == 1)
 450     {
 451       if (regs == 0)
 452         {
 453           *cycles = 4;
 454           /* PC relative.  */
 455           dst = msp430dis_opcode (addr + 2, info);
 456           cmd_len += 2;
 457           sprintf (op1, "0x%04x", PS (dst));
 458           sprintf (comm1, "PC rel. 0x%04x",
 459                    PS ((short) addr + 2 + dst));
 460         }
 461       else if (regs == 2)
 462         {
 463           *cycles = 2;
 464           /* Absolute.  */
 465           dst = msp430dis_opcode (addr + 2, info);
 466           cmd_len += 2;
 467           sprintf (op1, "&0x%04x", PS (dst));
 468           sprintf (comm1, "0x%04x", PS (dst));
 469         }
 470       else if (regs == 3)
 471         {
 472           *cycles = 1;
 473           sprintf (op1, "#1");
 474           sprintf (comm1, "r3 As==01");
 475         }
 476       else
 477         {
 478           *cycles = 3;
 479           /* Indexed.  */
 480           dst = msp430dis_opcode (addr + 2, info);
 481           cmd_len += 2;
 482           sprintf (op1, "%d(r%d)", dst, regs);
 483         }
 484     }
 485
 486   /* Destination. Special care needed on addr + XXXX.  */
 487
 488   if (ad == 0)
 489     {
 490       /* Register.  */
 491       if (regd == 0)
 492         {
 493           *cycles += 1;
 494           sprintf (op2, "r0");
 495         }
 496       else if (regd == 1)
 497         sprintf (op2, "r1");
 498
 499       else if (regd == 2)
 500         sprintf (op2, "r2");
 501
 502       else
 503         sprintf (op2, "r%d", regd);
 504     }
 505   else  /* ad == 1.  */
 506     {
 507       * cycles += 3;
 508
 509       if (regd == 0)
 510         {
 511           /* PC relative.  */
 512           *cycles += 1;
 513           dst = msp430dis_opcode (addr + cmd_len, info);
 514           sprintf (op2, "0x%04x", PS (dst));
 515           sprintf (comm2, "PC rel. 0x%04x",
 516                    PS ((short) addr + cmd_len + dst));
 517           cmd_len += 2;
 518         }
 519       else if (regd == 2)
 520         {
 521           /* Absolute.  */
 522           dst = msp430dis_opcode (addr + cmd_len, info);
 523           cmd_len += 2;
 524           sprintf (op2, "&0x%04x", PS (dst));
 525         }
 526       else
 527         {
 528           dst = msp430dis_opcode (addr + cmd_len, info);
 529           cmd_len += 2;
 530           sprintf (op2, "%d(r%d)", dst, regd);
 531         }
 532     }
 533
 534   return cmd_len;
 535 }
 536
 537 static int
 538 msp430_branchinstr (disassemble_info *info,
 539                     struct msp430_opcode_s *opcode ATTRIBUTE_UNUSED,
 540                     bfd_vma addr ATTRIBUTE_UNUSED,
 541                     unsigned short insn,
 542                     char *op1,
 543                     char *comm1,
 544                     int *cycles)
 545 {
 546   int regs = 0, regd = 0;
 547   int ad = 0, as = 0;
 548   int cmd_len = 2;
 549   short dst = 0;
 550
 551   regd = insn & 0x0f;
 552   regs = (insn & 0x0f00) >> 8;
 553   as = (insn & 0x0030) >> 4;
 554   ad = (insn & 0x0080) >> 7;
 555
 556   if (regd != 0)        /* Destination register is not a PC.  */
 557     return 0;
 558
 559   /* dst is a source register.  */
 560   if (as == 0)
 561     {
 562       /* Constants.  */
 563       if (regs == 3)
 564         {
 565           *cycles = 1;
 566           sprintf (op1, "#0");
 567           sprintf (comm1, "r3 As==00");
 568         }
 569       else
 570         {
 571           /* Register.  */
 572           *cycles = 1;
 573           sprintf (op1, "r%d", regs);
 574         }
 575     }
 576   else if (as == 2)
 577     {
 578       if (regs == 2)
 579         {
 580           *cycles = 2;
 581           sprintf (op1, "#4");
 582           sprintf (comm1, "r2 As==10");
 583         }
 584       else if (regs == 3)
 585         {
 586           *cycles = 1;
 587           sprintf (op1, "#2");
 588           sprintf (comm1, "r3 As==10");
 589         }
 590       else
 591         {
 592           /* Indexed register mode @Rn.  */
 593           *cycles = 2;
 594           sprintf (op1, "@r%d", regs);
 595         }
 596     }
 597   else if (as == 3)
 598     {
 599       if (regs == 2)
 600         {
 601           *cycles = 1;
 602           sprintf (op1, "#8");
 603           sprintf (comm1, "r2 As==11");
 604         }
 605       else if (regs == 3)
 606         {
 607           *cycles = 1;
 608           sprintf (op1, "#-1");
 609           sprintf (comm1, "r3 As==11");
 610         }
 611       else if (regs == 0)
 612         {
 613           /* Absolute. @pc+  */
 614           *cycles = 3;
 615           dst = msp430dis_opcode (addr + 2, info);
 616           cmd_len += 2;
 617           sprintf (op1, "#0x%04x", PS (dst));
 618         }
 619       else
 620         {
 621           *cycles = 2;
 622           sprintf (op1, "@r%d+", regs);
 623         }
 624     }
 625   else if (as == 1)
 626     {
 627       * cycles = 3;
 628
 629       if (regs == 0)
 630         {
 631           /* PC relative.  */
 632           dst = msp430dis_opcode (addr + 2, info);
 633           cmd_len += 2;
 634           (*cycles)++;
 635           sprintf (op1, "0x%04x", PS (dst));
 636           sprintf (comm1, "PC rel. 0x%04x",
 637                    PS ((short) addr + 2 + dst));
 638         }
 639       else if (regs == 2)
 640         {
 641           /* Absolute.  */
 642           dst = msp430dis_opcode (addr + 2, info);
 643           cmd_len += 2;
 644           sprintf (op1, "&0x%04x", PS (dst));
 645         }
 646       else if (regs == 3)
 647         {
 648           (*cycles)--;
 649           sprintf (op1, "#1");
 650           sprintf (comm1, "r3 As==01");
 651         }
 652       else
 653         {
 654           /* Indexd.  */
 655           dst = msp430dis_opcode (addr + 2, info);
 656           cmd_len += 2;
 657           sprintf (op1, "%d(r%d)", dst, regs);
 658         }
 659     }
 660
 661   return cmd_len;
 662 }
 663
 664 int
 665 print_insn_msp430 (bfd_vma addr, disassemble_info *info)
 666 {
 667   void *stream = info->stream;
 668   fprintf_ftype prin = info->fprintf_func;
 669   struct msp430_opcode_s *opcode;
 670   char op1[32], op2[32], comm1[64], comm2[64];
 671   int cmd_len = 0;
 672   unsigned short insn;
 673   int cycles = 0;
 674   char *bc = "";
 675   char dinfo[32];               /* Debug purposes.  */
 676
 677   insn = msp430dis_opcode (addr, info);
 678   sprintf (dinfo, "0x%04x", insn);
 679
 680   if (((int) addr & 0xffff) > 0xffdf)
 681     {
 682       (*prin) (stream, "interrupt service routine at 0x%04x", 0xffff & insn);
 683       return 2;
 684     }
 685
 686   *comm1 = 0;
 687   *comm2 = 0;
 688
 689   for (opcode = msp430_opcodes; opcode->name; opcode++)
 690     {
 691       if ((insn & opcode->bin_mask) == opcode->bin_opcode
 692           && opcode->bin_opcode != 0x9300)
 693         {
 694           *op1 = 0;
 695           *op2 = 0;
 696           *comm1 = 0;
 697           *comm2 = 0;
 698
 699           /* r0 as destination. Ad should be zero.  */
 700           if (opcode->insn_opnumb == 3 && (insn & 0x000f) == 0
 701               && (0x0080 & insn) == 0)
 702             {
 703               cmd_len =
 704                 msp430_branchinstr (info, opcode, addr, insn, op1, comm1,
 705                                     &cycles);
 706               if (cmd_len)
 707                 break;
 708             }
 709
 710           switch (opcode->insn_opnumb)
 711             {
 712             case 0:
 713               cmd_len = msp430_nooperands (opcode, addr, insn, comm1, &cycles);
 714               break;
 715             case 2:
 716               cmd_len =
 717                 msp430_doubleoperand (info, opcode, addr, insn, op1, op2,
 718                                       comm1, comm2, &cycles);
 719               if (insn & BYTE_OPERATION)
 720                 bc = ".b";
 721               break;
 722             case 1:
 723               cmd_len =
 724                 msp430_singleoperand (info, opcode, addr, insn, op1, comm1,
 725                                       &cycles);
 726               if (insn & BYTE_OPERATION && opcode->fmt != 3)
 727                 bc = ".b";
 728               break;
 729             default:
 730               break;
 731             }
 732         }
 733
 734       if (cmd_len)
 735         break;
 736     }
 737
 738   dinfo[5] = 0;
 739
 740   if (cmd_len < 1)
 741     {
 742       /* Unknown opcode, or invalid combination of operands.  */
 743       (*prin) (stream, ".word   0x%04x; ????", PS (insn));
 744       return 2;
 745     }
 746
 747   (*prin) (stream, "%s%s", opcode->name, bc);
 748
 749   if (*op1)
 750     (*prin) (stream, "\t%s", op1);
 751   if (*op2)
 752     (*prin) (stream, ",");
 753
 754   if (strlen (op1) < 7)
 755     (*prin) (stream, "\t");
 756   if (!strlen (op1))
 757     (*prin) (stream, "\t");
 758
 759   if (*op2)
 760     (*prin) (stream, "%s", op2);
 761   if (strlen (op2) < 8)
 762     (*prin) (stream, "\t");
 763
 764   if (*comm1 || *comm2)
 765     (*prin) (stream, ";");
 766   else if (cycles)
 767     {
 768       if (*op2)
 769         (*prin) (stream, ";");
 770       else
 771         {
 772           if (strlen (op1) < 7)
 773             (*prin) (stream, ";");
 774           else
 775             (*prin) (stream, "\t;");
 776         }
 777     }
 778   if (*comm1)
 779     (*prin) (stream, "%s", comm1);
 780   if (*comm1 && *comm2)
 781     (*prin) (stream, ",");
 782   if (*comm2)
 783     (*prin) (stream, " %s", comm2);
 784   return cmd_len;
 785 }