opcodes/sh64-dis.c

   1 /* Disassemble SH64 instructions.
   2    Copyright (C) 2000-2017 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU opcodes library.
   5
   6    This library 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 3, or (at your option)
   9    any later version.
  10
  11    It is distributed in the hope that it will be useful, but WITHOUT
  12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  14    License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this file; see the file COPYING.  If not, write to the
  18    Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include <stdio.h>
  23 #include "disassemble.h"
  24 #include "sh64-opc.h"
  25 #include "libiberty.h"
  26 /* We need to refer to the ELF header structure.  */
  27 #include "elf-bfd.h"
  28 #include "elf/sh.h"
  29 #include "elf32-sh64.h"
  30
  31 #define ELF_MODE32_CODE_LABEL_P(SYM) \
  32  (((elf_symbol_type *) (SYM))->internal_elf_sym.st_other & STO_SH5_ISA32)
  33
  34 #define SAVED_MOVI_R(INFO) \
  35  (((struct sh64_disassemble_info *) ((INFO)->private_data))->address_reg)
  36
  37 #define SAVED_MOVI_IMM(INFO) \
  38  (((struct sh64_disassemble_info *) ((INFO)->private_data))->built_address)
  39
  40 struct sh64_disassemble_info
  41  {
  42    /* When we see a MOVI, we save the register and the value, and merge a
  43       subsequent SHORI and display the address, if there is one.  */
  44    unsigned int address_reg;
  45    bfd_signed_vma built_address;
  46
  47    /* This is the range decriptor for the current address.  It is kept
  48       around for the next call.  */
  49    sh64_elf_crange crange;
  50  };
  51
  52 /* Each item in the table is a mask to indicate which bits to be set
  53    to determine an instruction's operator.
  54    The index is as same as the instruction in the opcode table.
  55    Note that some archs have this as a field in the opcode table.  */
  56 static unsigned long *shmedia_opcode_mask_table;
  57
  58 /* Initialize the SH64 opcode mask table for each instruction in SHmedia
  59    mode.  */
  60
  61 static void
  62 initialize_shmedia_opcode_mask_table (void)
  63 {
  64   int n_opc;
  65   int n;
  66
  67   /* Calculate number of opcodes.  */
  68   for (n_opc = 0; shmedia_table[n_opc].name != NULL; n_opc++)
  69     ;
  70
  71   shmedia_opcode_mask_table
  72     = xmalloc (sizeof (shmedia_opcode_mask_table[0]) * n_opc);
  73
  74   for (n = 0; n < n_opc; n++)
  75     {
  76       int i;
  77
  78       unsigned long mask = 0;
  79
  80       for (i = 0; shmedia_table[n].arg[i] != A_NONE; i++)
  81         {
  82           int offset = shmedia_table[n].nibbles[i];
  83           int length;
  84
  85           switch (shmedia_table[n].arg[i])
  86             {
  87             case A_GREG_M:
  88             case A_GREG_N:
  89             case A_GREG_D:
  90             case A_CREG_K:
  91             case A_CREG_J:
  92             case A_FREG_G:
  93             case A_FREG_H:
  94             case A_FREG_F:
  95             case A_DREG_G:
  96             case A_DREG_H:
  97             case A_DREG_F:
  98             case A_FMREG_G:
  99             case A_FMREG_H:
 100             case A_FMREG_F:
 101             case A_FPREG_G:
 102             case A_FPREG_H:
 103             case A_FPREG_F:
 104             case A_FVREG_G:
 105             case A_FVREG_H:
 106             case A_FVREG_F:
 107             case A_REUSE_PREV:
 108               length = 6;
 109               break;
 110
 111             case A_TREG_A:
 112             case A_TREG_B:
 113               length = 3;
 114               break;
 115
 116             case A_IMMM:
 117               abort ();
 118               break;
 119
 120             case A_IMMU5:
 121               length = 5;
 122               break;
 123
 124             case A_IMMS6:
 125             case A_IMMU6:
 126             case A_IMMS6BY32:
 127               length = 6;
 128               break;
 129
 130             case A_IMMS10:
 131             case A_IMMS10BY1:
 132             case A_IMMS10BY2:
 133             case A_IMMS10BY4:
 134             case A_IMMS10BY8:
 135               length = 10;
 136               break;
 137
 138             case A_IMMU16:
 139             case A_IMMS16:
 140             case A_PCIMMS16BY4:
 141             case A_PCIMMS16BY4_PT:
 142               length = 16;
 143               break;
 144
 145             default:
 146               abort ();
 147               length = 0;
 148               break;
 149             }
 150
 151           if (length != 0)
 152             mask |= (0xffffffff >> (32 - length)) << offset;
 153         }
 154       shmedia_opcode_mask_table[n] = 0xffffffff & ~mask;
 155     }
 156 }
 157
 158 /* Get a predefined control-register-name, or return NULL.  */
 159
 160 static const char *
 161 creg_name (int cregno)
 162 {
 163   const shmedia_creg_info *cregp;
 164
 165   /* If control register usage is common enough, change this to search a
 166      hash-table.  */
 167   for (cregp = shmedia_creg_table; cregp->name != NULL; cregp++)
 168     if (cregp->cregno == cregno)
 169       return cregp->name;
 170
 171   return NULL;
 172 }
 173
 174 /* Main function to disassemble SHmedia instructions.  */
 175
 176 static int
 177 print_insn_shmedia (bfd_vma memaddr, struct disassemble_info *info)
 178 {
 179   fprintf_ftype fprintf_fn = info->fprintf_func;
 180   void *stream = info->stream;
 181   unsigned char insn[4];
 182   unsigned long instruction;
 183   int status;
 184   int n;
 185   const shmedia_opcode_info *op;
 186   int i;
 187   unsigned int r = 0;
 188   long imm = 0;
 189   bfd_vma disp_pc_addr;
 190
 191   status = info->read_memory_func (memaddr, insn, 4, info);
 192
 193   /* If we can't read four bytes, something is wrong.  Display any data we
 194      can get as .byte:s.  */
 195   if (status != 0)
 196     {
 197       for (i = 0; i < 3; i++)
 198         {
 199           status = info->read_memory_func (memaddr + i, insn, 1, info);
 200           if (status != 0)
 201             break;
 202           (*fprintf_fn) (stream, "%s0x%02x",
 203                          i == 0 ? ".byte " : ", ",
 204                          insn[0]);
 205         }
 206
 207       return i ? i : -1;
 208     }
 209
 210   /* Rearrange the bytes to make up an instruction.  */
 211   if (info->endian == BFD_ENDIAN_LITTLE)
 212     instruction = bfd_getl32 (insn);
 213   else
 214     instruction = bfd_getb32 (insn);
 215
 216   /* FIXME: Searching could be implemented using a hash on relevant
 217      fields.  */
 218   for (n = 0, op = shmedia_table;
 219        op->name != NULL
 220        && ((instruction & shmedia_opcode_mask_table[n]) != op->opcode_base);
 221        n++, op++)
 222     ;
 223
 224   /* FIXME: We should also check register number constraints.  */
 225   if (op->name == NULL)
 226     {
 227       fprintf_fn (stream, ".long 0x%08lx", instruction);
 228       return 4;
 229     }
 230
 231   fprintf_fn (stream, "%s\t", op->name);
 232
 233   for (i = 0; i < 3 && op->arg[i] != A_NONE; i++)
 234     {
 235       unsigned long temp = instruction >> op->nibbles[i];
 236       int by_number = 0;
 237
 238       if (i > 0 && op->arg[i] != A_REUSE_PREV)
 239         fprintf_fn (stream, ",");
 240
 241       switch (op->arg[i])
 242         {
 243         case A_REUSE_PREV:
 244           continue;
 245
 246         case A_GREG_M:
 247         case A_GREG_N:
 248         case A_GREG_D:
 249           r = temp & 0x3f;
 250           fprintf_fn (stream, "r%d", r);
 251           break;
 252
 253         case A_FVREG_F:
 254         case A_FVREG_G:
 255         case A_FVREG_H:
 256           r = temp & 0x3f;
 257           fprintf_fn (stream, "fv%d", r);
 258           break;
 259
 260         case A_FPREG_F:
 261         case A_FPREG_G:
 262         case A_FPREG_H:
 263           r = temp & 0x3f;
 264           fprintf_fn (stream, "fp%d", r);
 265           break;
 266
 267         case A_FMREG_F:
 268         case A_FMREG_G:
 269         case A_FMREG_H:
 270           r = temp & 0x3f;
 271           fprintf_fn (stream, "mtrx%d", r);
 272           break;
 273
 274         case A_CREG_K:
 275         case A_CREG_J:
 276           {
 277             const char *name;
 278
 279             r = temp & 0x3f;
 280
 281             name = creg_name (r);
 282
 283             if (name != NULL)
 284               fprintf_fn (stream, "%s", name);
 285             else
 286               fprintf_fn (stream, "cr%d", r);
 287           }
 288           break;
 289
 290         case A_FREG_G:
 291         case A_FREG_H:
 292         case A_FREG_F:
 293           r = temp & 0x3f;
 294           fprintf_fn (stream, "fr%d", r);
 295           break;
 296
 297         case A_DREG_G:
 298         case A_DREG_H:
 299         case A_DREG_F:
 300           r = temp & 0x3f;
 301           fprintf_fn (stream, "dr%d", r);
 302           break;
 303
 304         case A_TREG_A:
 305         case A_TREG_B:
 306           r = temp & 0x7;
 307           fprintf_fn (stream, "tr%d", r);
 308           break;
 309
 310           /* A signed 6-bit number.  */
 311         case A_IMMS6:
 312           imm = temp & 0x3f;
 313           if (imm & (unsigned long) 0x20)
 314             imm |= ~(unsigned long) 0x3f;
 315           fprintf_fn (stream, "%ld", imm);
 316           break;
 317
 318           /* A signed 6-bit number, multiplied by 32 when used.  */
 319         case A_IMMS6BY32:
 320           imm = temp & 0x3f;
 321           if (imm & (unsigned long) 0x20)
 322             imm |= ~(unsigned long) 0x3f;
 323           fprintf_fn (stream, "%ld", imm * 32);
 324           break;
 325
 326           /* A signed 10-bit number, multiplied by 8 when used.  */
 327         case A_IMMS10BY8:
 328           by_number++;
 329           /* Fall through.  */
 330
 331           /* A signed 10-bit number, multiplied by 4 when used.  */
 332         case A_IMMS10BY4:
 333           by_number++;
 334           /* Fall through.  */
 335
 336           /* A signed 10-bit number, multiplied by 2 when used.  */
 337         case A_IMMS10BY2:
 338           by_number++;
 339           /* Fall through.  */
 340
 341           /* A signed 10-bit number.  */
 342         case A_IMMS10:
 343         case A_IMMS10BY1:
 344           imm = temp & 0x3ff;
 345           if (imm & (unsigned long) 0x200)
 346             imm |= ~(unsigned long) 0x3ff;
 347           imm <<= by_number;
 348           fprintf_fn (stream, "%ld", imm);
 349           break;
 350
 351           /* A signed 16-bit number.  */
 352         case A_IMMS16:
 353           imm = temp & 0xffff;
 354           if (imm & (unsigned long) 0x8000)
 355             imm |= ~((unsigned long) 0xffff);
 356           fprintf_fn (stream, "%ld", imm);
 357           break;
 358
 359           /* A PC-relative signed 16-bit number, multiplied by 4 when
 360              used.  */
 361         case A_PCIMMS16BY4:
 362           imm = temp & 0xffff;  /* 16 bits */
 363           if (imm & (unsigned long) 0x8000)
 364             imm |= ~(unsigned long) 0xffff;
 365           imm <<= 2;
 366           disp_pc_addr = (bfd_vma) imm + memaddr;
 367           (*info->print_address_func) (disp_pc_addr, info);
 368           break;
 369
 370           /* An unsigned 5-bit number.  */
 371         case A_IMMU5:
 372           imm = temp & 0x1f;
 373           fprintf_fn (stream, "%ld", imm);
 374           break;
 375
 376           /* An unsigned 6-bit number.  */
 377         case A_IMMU6:
 378           imm = temp & 0x3f;
 379           fprintf_fn (stream, "%ld", imm);
 380           break;
 381
 382           /* An unsigned 16-bit number.  */
 383         case A_IMMU16:
 384           imm = temp & 0xffff;
 385           fprintf_fn (stream, "%ld", imm);
 386           break;
 387
 388         default:
 389           abort ();
 390           break;
 391         }
 392     }
 393
 394   /* FIXME: Looks like 32-bit values only are handled.
 395      FIXME: PC-relative numbers aren't handled correctly.  */
 396   if (op->opcode_base == (unsigned long) SHMEDIA_SHORI_OPC
 397       && SAVED_MOVI_R (info) == r)
 398     {
 399       asection *section = info->section;
 400
 401       /* Most callers do not set the section field correctly yet.  Revert
 402          to getting the section from symbols, if any. */
 403       if (section == NULL
 404           && info->symbols != NULL
 405           && bfd_asymbol_flavour (info->symbols[0]) == bfd_target_elf_flavour
 406           && ! bfd_is_und_section (bfd_get_section (info->symbols[0]))
 407           && ! bfd_is_abs_section (bfd_get_section (info->symbols[0])))
 408         section = bfd_get_section (info->symbols[0]);
 409
 410       /* Only guess addresses when the contents of this section is fully
 411          relocated.  Otherwise, the value will be zero or perhaps even
 412          bogus.  */
 413       if (section == NULL
 414           || section->owner == NULL
 415           || elf_elfheader (section->owner)->e_type == ET_EXEC)
 416         {
 417           bfd_signed_vma shori_addr;
 418
 419           shori_addr = SAVED_MOVI_IMM (info) << 16;
 420           shori_addr |= imm;
 421
 422           fprintf_fn (stream, "\t! 0x");
 423           (*info->print_address_func) (shori_addr, info);
 424         }
 425     }
 426
 427   if (op->opcode_base == SHMEDIA_MOVI_OPC)
 428     {
 429       SAVED_MOVI_IMM (info) = imm;
 430       SAVED_MOVI_R (info) = r;
 431     }
 432   else
 433     {
 434       SAVED_MOVI_IMM (info) = 0;
 435       SAVED_MOVI_R (info) = 255;
 436     }
 437
 438   return 4;
 439 }
 440
 441 /* Check the type of contents about to be disassembled.  This is like
 442    sh64_get_contents_type (which may be called from here), except that it
 443    takes the same arguments as print_insn_* and does what can be done if
 444    no section is available.  */
 445
 446 static enum sh64_elf_cr_type
 447 sh64_get_contents_type_disasm (bfd_vma memaddr, struct disassemble_info *info)
 448 {
 449   struct sh64_disassemble_info *sh64_infop = info->private_data;
 450
 451   /* Perhaps we have a region from a previous probe and it still counts
 452      for this address?  */
 453   if (sh64_infop->crange.cr_type != CRT_NONE
 454       && memaddr >= sh64_infop->crange.cr_addr
 455       && memaddr < sh64_infop->crange.cr_addr + sh64_infop->crange.cr_size)
 456     return sh64_infop->crange.cr_type;
 457
 458   /* If we have a section, try and use it.  */
 459   if (info->section
 460       && bfd_get_flavour (info->section->owner) == bfd_target_elf_flavour)
 461     {
 462       enum sh64_elf_cr_type cr_type
 463         = sh64_get_contents_type (info->section, memaddr,
 464                                   &sh64_infop->crange);
 465
 466       if (cr_type != CRT_NONE)
 467         return cr_type;
 468     }
 469
 470   /* If we have symbols, we can try and get at a section from *that*.  */
 471   if (info->symbols != NULL
 472       && bfd_asymbol_flavour (info->symbols[0]) == bfd_target_elf_flavour
 473       && ! bfd_is_und_section (bfd_get_section (info->symbols[0]))
 474       && ! bfd_is_abs_section (bfd_get_section (info->symbols[0])))
 475     {
 476       enum sh64_elf_cr_type cr_type
 477         = sh64_get_contents_type (bfd_get_section (info->symbols[0]),
 478                                   memaddr, &sh64_infop->crange);
 479
 480       if (cr_type != CRT_NONE)
 481         return cr_type;
 482     }
 483
 484   /* We can make a reasonable guess based on the st_other field of a
 485      symbol; for a BranchTarget this is marked as STO_SH5_ISA32 and then
 486      it's most probably code there.  */
 487   if (info->symbols
 488       && bfd_asymbol_flavour (info->symbols[0]) == bfd_target_elf_flavour
 489       && elf_symbol_from (bfd_asymbol_bfd (info->symbols[0]),
 490                           info->symbols[0])->internal_elf_sym.st_other
 491       == STO_SH5_ISA32)
 492     return CRT_SH5_ISA32;
 493
 494   /* If all else fails, guess this is code and guess on the low bit set.  */
 495   return (memaddr & 1) == 1 ? CRT_SH5_ISA32 : CRT_SH5_ISA16;
 496 }
 497
 498 /* Initialize static and dynamic disassembly state.  */
 499
 500 static bfd_boolean
 501 init_sh64_disasm_info (struct disassemble_info *info)
 502 {
 503   struct sh64_disassemble_info *sh64_infop
 504     = calloc (sizeof (*sh64_infop), 1);
 505
 506   if (sh64_infop == NULL)
 507     return FALSE;
 508
 509   info->private_data = sh64_infop;
 510
 511   SAVED_MOVI_IMM (info) = 0;
 512   SAVED_MOVI_R (info) = 255;
 513
 514   if (shmedia_opcode_mask_table == NULL)
 515     initialize_shmedia_opcode_mask_table ();
 516
 517   return TRUE;
 518 }
 519
 520 /* Main entry to disassemble SHmedia instructions, given an endian set in
 521    INFO.  Note that the simulator uses this as the main entry and does not
 522    use any of the functions further below.  */
 523
 524 int
 525 print_insn_sh64x_media (bfd_vma memaddr, struct disassemble_info *info)
 526 {
 527   if (info->private_data == NULL && ! init_sh64_disasm_info (info))
 528     return -1;
 529
 530   /* Make reasonable output.  */
 531   info->bytes_per_line = 4;
 532   info->bytes_per_chunk = 4;
 533
 534   return print_insn_shmedia (memaddr, info);
 535 }
 536
 537 /* Main entry to disassemble SHmedia insns.
 538    If we see an SHcompact instruction, return -2.  */
 539
 540 int
 541 print_insn_sh64 (bfd_vma memaddr, struct disassemble_info *info)
 542 {
 543   enum bfd_endian endian = info->endian;
 544   enum sh64_elf_cr_type cr_type;
 545
 546   if (info->private_data == NULL && ! init_sh64_disasm_info (info))
 547     return -1;
 548
 549   cr_type = sh64_get_contents_type_disasm (memaddr, info);
 550   if (cr_type != CRT_SH5_ISA16)
 551     {
 552       int length = 4 - (memaddr % 4);
 553       info->display_endian = endian;
 554
 555       /* If we got an uneven address to indicate SHmedia, adjust it.  */
 556       if (cr_type == CRT_SH5_ISA32 && length == 3)
 557         memaddr--, length = 4;
 558
 559       /* Only disassemble on four-byte boundaries.  Addresses that are not
 560          a multiple of four can happen after a data region.  */
 561       if (cr_type == CRT_SH5_ISA32 && length == 4)
 562         return print_insn_sh64x_media (memaddr, info);
 563
 564       /* We get CRT_DATA *only* for data regions in a mixed-contents
 565          section.  For sections with data only, we get indication of one
 566          of the ISA:s.  You may think that we shouldn't disassemble
 567          section with only data if we can figure that out.  However, the
 568          disassembly function is by default not called for data-only
 569          sections, so if the user explicitly specified disassembly of a
 570          data section, that's what we should do.  */
 571       if (cr_type == CRT_DATA || length != 4)
 572         {
 573           int status;
 574           unsigned char data[4];
 575           struct sh64_disassemble_info *sh64_infop = info->private_data;
 576
 577           if (length == 4
 578               && sh64_infop->crange.cr_type != CRT_NONE
 579               && memaddr >= sh64_infop->crange.cr_addr
 580               && memaddr < (sh64_infop->crange.cr_addr
 581                             + sh64_infop->crange.cr_size))
 582             length
 583               = (sh64_infop->crange.cr_addr
 584                  + sh64_infop->crange.cr_size - memaddr);
 585
 586           status
 587             = (*info->read_memory_func) (memaddr, data,
 588                                          length >= 4 ? 4 : length, info);
 589
 590           if (status == 0 && length >= 4)
 591             {
 592               (*info->fprintf_func) (info->stream, ".long 0x%08lx",
 593                                      endian == BFD_ENDIAN_BIG
 594                                      ? (long) (bfd_getb32 (data))
 595                                      : (long) (bfd_getl32 (data)));
 596               return 4;
 597             }
 598           else
 599             {
 600               int i;
 601
 602               for (i = 0; i < length; i++)
 603                 {
 604                   status = info->read_memory_func (memaddr + i, data, 1, info);
 605                   if (status != 0)
 606                     break;
 607                   (*info->fprintf_func) (info->stream, "%s0x%02x",
 608                                          i == 0 ? ".byte " : ", ",
 609                                          data[0]);
 610                 }
 611
 612               return i ? i : -1;
 613             }
 614         }
 615     }
 616
 617   /* SH1 .. SH4 instruction, let caller handle it.  */
 618   return -2;
 619 }