opcodes/mips-dis.c

   1 /* Print mips instructions for GDB, the GNU debugger, or for objdump.
   2    Copyright 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   3    2000, 2001, 2002
   4    Free Software Foundation, Inc.
   5    Contributed by Nobuyuki Hikichi(hikichi@sra.co.jp).
   6
   7 This file is part of GDB, GAS, and the GNU binutils.
   8
   9 This program is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2 of the License, or
  12 (at your option) any later version.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  22
  23 #include "sysdep.h"
  24 #include "dis-asm.h"
  25 #include "opcode/mips.h"
  26 #include "opintl.h"
  27
  28 /* FIXME: These are needed to figure out if the code is mips16 or
  29    not. The low bit of the address is often a good indicator.  No
  30    symbol table is available when this code runs out in an embedded
  31    system as when it is used for disassembler support in a monitor.  */
  32
  33 #if !defined(EMBEDDED_ENV)
  34 #define SYMTAB_AVAILABLE 1
  35 #include "elf-bfd.h"
  36 #include "elf/mips.h"
  37 #endif
  38
  39 /* Mips instructions are at maximum this many bytes long.  */
  40 #define INSNLEN 4
  41
  42 static int _print_insn_mips
  43   PARAMS ((bfd_vma, struct disassemble_info *, enum bfd_endian));
  44 static int print_insn_mips
  45   PARAMS ((bfd_vma, unsigned long int, struct disassemble_info *));
  46 static void print_insn_arg
  47   PARAMS ((const char *, unsigned long, bfd_vma, struct disassemble_info *));
  48 static void mips_isa_type
  49   PARAMS ((int, int *, int *));
  50 static int print_insn_mips16
  51   PARAMS ((bfd_vma, struct disassemble_info *));
  52 static int is_newabi
  53   PARAMS ((Elf_Internal_Ehdr *));
  54 static void print_mips16_insn_arg
  55   PARAMS ((int, const struct mips_opcode *, int, boolean, int, bfd_vma,
  56            struct disassemble_info *));
  57 \f
  58 /* FIXME: These should be shared with gdb somehow.  */
  59
  60 /* The mips16 register names.  */
  61 static const char * const mips16_reg_names[] = {
  62   "s0", "s1", "v0", "v1", "a0", "a1", "a2", "a3"
  63 };
  64
  65 static const char * const mips32_reg_names[] = {
  66   "zero", "at",   "v0",  "v1",   "a0",    "a1",    "a2",   "a3",
  67   "t0",   "t1",   "t2",  "t3",   "t4",    "t5",    "t6",   "t7",
  68   "s0",   "s1",   "s2",  "s3",   "s4",    "s5",    "s6",   "s7",
  69   "t8",   "t9",   "k0",  "k1",   "gp",    "sp",    "s8",   "ra",
  70   "sr",   "lo",   "hi",  "bad",  "cause", "pc",
  71   "fv0",  "$f1",  "fv1", "$f3",  "ft0",   "$f5",   "ft1",  "$f7",
  72   "ft2",  "$f9",  "ft3", "$f11", "fa0",   "$f13",  "fa1",  "$f15",
  73   "ft4",  "f17",  "ft5", "f19",  "fs0",   "f21",   "fs1",  "f23",
  74   "fs2",  "$f25", "fs3", "$f27", "fs4",   "$f29",  "fs5",  "$f31",
  75   "fsr",  "fir",  "fp",  "inx",  "rand",  "tlblo", "ctxt", "tlbhi",
  76   "epc",  "prid"
  77 };
  78
  79 static const char * const mips64_reg_names[] = {
  80   "zero", "at",   "v0",   "v1",   "a0",    "a1",    "a2",   "a3",
  81   "a4",   "a5",   "a6",   "a7",   "t0",    "t1",    "t2",   "t3",
  82   "s0",   "s1",   "s2",   "s3",   "s4",    "s5",    "s6",   "s7",
  83   "t8",   "t9",   "k0",   "k1",   "gp",    "sp",    "s8",   "ra",
  84   "sr",   "lo",   "hi",   "bad",  "cause", "pc",
  85   "fv0",  "$f1",  "fv1",  "$f3",  "ft0",   "ft1",   "ft2",  "ft3",
  86   "ft4",  "ft5",  "ft6",  "ft7",  "fa0",   "fa1",   "fa2",  "fa3",
  87   "fa4",  "fa5",  "fa6",  "fa7",  "ft8",   "ft9",   "ft10", "ft11",
  88   "fs0",  "fs1",  "fs2",  "fs3",  "fs4",   "fs5",   "fs6",  "fs7",
  89   "fsr",  "fir",  "fp",   "inx",  "rand",  "tlblo", "ctxt", "tlbhi",
  90   "epc",  "prid"
  91 };
  92
  93 /* Scalar register names. _print_insn_mips() decides which register name
  94    table to use.  */
  95 static const char * const *reg_names = NULL;
  96 \f
  97 /* Print insn arguments for 32/64-bit code.  */
  98
  99 static void
 100 print_insn_arg (d, l, pc, info)
 101      const char *d;
 102      register unsigned long int l;
 103      bfd_vma pc;
 104      struct disassemble_info *info;
 105 {
 106   int delta;
 107
 108   switch (*d)
 109     {
 110     case ',':
 111     case '(':
 112     case ')':
 113       (*info->fprintf_func) (info->stream, "%c", *d);
 114       break;
 115
 116     case 's':
 117     case 'b':
 118     case 'r':
 119     case 'v':
 120       (*info->fprintf_func) (info->stream, "%s",
 121                              reg_names[(l >> OP_SH_RS) & OP_MASK_RS]);
 122       break;
 123
 124     case 't':
 125     case 'w':
 126       (*info->fprintf_func) (info->stream, "%s",
 127                              reg_names[(l >> OP_SH_RT) & OP_MASK_RT]);
 128       break;
 129
 130     case 'i':
 131     case 'u':
 132       (*info->fprintf_func) (info->stream, "0x%x",
 133                              (l >> OP_SH_IMMEDIATE) & OP_MASK_IMMEDIATE);
 134       break;
 135
 136     case 'j': /* Same as i, but sign-extended.  */
 137     case 'o':
 138       delta = (l >> OP_SH_DELTA) & OP_MASK_DELTA;
 139       if (delta & 0x8000)
 140         delta |= ~0xffff;
 141       (*info->fprintf_func) (info->stream, "%d",
 142                              delta);
 143       break;
 144
 145     case 'h':
 146       (*info->fprintf_func) (info->stream, "0x%x",
 147                              (unsigned int) ((l >> OP_SH_PREFX)
 148                                              & OP_MASK_PREFX));
 149       break;
 150
 151     case 'k':
 152       (*info->fprintf_func) (info->stream, "0x%x",
 153                              (unsigned int) ((l >> OP_SH_CACHE)
 154                                              & OP_MASK_CACHE));
 155       break;
 156
 157     case 'a':
 158       info->target = (((pc + 4) & ~(bfd_vma) 0x0fffffff)
 159                       | (((l >> OP_SH_TARGET) & OP_MASK_TARGET) << 2));
 160       (*info->print_address_func) (info->target, info);
 161       break;
 162
 163     case 'p':
 164       /* Sign extend the displacement.  */
 165       delta = (l >> OP_SH_DELTA) & OP_MASK_DELTA;
 166       if (delta & 0x8000)
 167         delta |= ~0xffff;
 168       info->target = (delta << 2) + pc + INSNLEN;
 169       (*info->print_address_func) (info->target, info);
 170       break;
 171
 172     case 'd':
 173       (*info->fprintf_func) (info->stream, "%s",
 174                              reg_names[(l >> OP_SH_RD) & OP_MASK_RD]);
 175       break;
 176
 177     case 'U':
 178       {
 179         /* First check for both rd and rt being equal.  */
 180         unsigned int reg = (l >> OP_SH_RD) & OP_MASK_RD;
 181         if (reg == ((l >> OP_SH_RT) & OP_MASK_RT))
 182           (*info->fprintf_func) (info->stream, "%s",
 183                                  reg_names[reg]);
 184         else
 185           {
 186             /* If one is zero use the other.  */
 187             if (reg == 0)
 188               (*info->fprintf_func) (info->stream, "%s",
 189                                      reg_names[(l >> OP_SH_RT) & OP_MASK_RT]);
 190             else if (((l >> OP_SH_RT) & OP_MASK_RT) == 0)
 191               (*info->fprintf_func) (info->stream, "%s",
 192                                      reg_names[reg]);
 193             else /* Bogus, result depends on processor.  */
 194               (*info->fprintf_func) (info->stream, "%s or %s",
 195                                      reg_names[reg],
 196                                      reg_names[(l >> OP_SH_RT) & OP_MASK_RT]);
 197           }
 198       }
 199       break;
 200
 201     case 'z':
 202       (*info->fprintf_func) (info->stream, "%s", reg_names[0]);
 203       break;
 204
 205     case '<':
 206       (*info->fprintf_func) (info->stream, "0x%x",
 207                              (l >> OP_SH_SHAMT) & OP_MASK_SHAMT);
 208       break;
 209
 210     case 'c':
 211       (*info->fprintf_func) (info->stream, "0x%x",
 212                              (l >> OP_SH_CODE) & OP_MASK_CODE);
 213       break;
 214
 215     case 'q':
 216       (*info->fprintf_func) (info->stream, "0x%x",
 217                              (l >> OP_SH_CODE2) & OP_MASK_CODE2);
 218       break;
 219
 220     case 'C':
 221       (*info->fprintf_func) (info->stream, "0x%x",
 222                              (l >> OP_SH_COPZ) & OP_MASK_COPZ);
 223       break;
 224
 225     case 'B':
 226       (*info->fprintf_func) (info->stream, "0x%x",
 227                              (l >> OP_SH_CODE20) & OP_MASK_CODE20);
 228       break;
 229
 230     case 'J':
 231       (*info->fprintf_func) (info->stream, "0x%x",
 232                              (l >> OP_SH_CODE19) & OP_MASK_CODE19);
 233       break;
 234
 235     case 'S':
 236     case 'V':
 237       (*info->fprintf_func) (info->stream, "$f%d",
 238                              (l >> OP_SH_FS) & OP_MASK_FS);
 239       break;
 240
 241     case 'T':
 242     case 'W':
 243       (*info->fprintf_func) (info->stream, "$f%d",
 244                              (l >> OP_SH_FT) & OP_MASK_FT);
 245       break;
 246
 247     case 'D':
 248       (*info->fprintf_func) (info->stream, "$f%d",
 249                              (l >> OP_SH_FD) & OP_MASK_FD);
 250       break;
 251
 252     case 'R':
 253       (*info->fprintf_func) (info->stream, "$f%d",
 254                              (l >> OP_SH_FR) & OP_MASK_FR);
 255       break;
 256
 257     case 'E':
 258       (*info->fprintf_func) (info->stream, "$%d",
 259                              (l >> OP_SH_RT) & OP_MASK_RT);
 260       break;
 261
 262     case 'G':
 263       (*info->fprintf_func) (info->stream, "$%d",
 264                              (l >> OP_SH_RD) & OP_MASK_RD);
 265       break;
 266
 267     case 'N':
 268       (*info->fprintf_func) (info->stream, "$fcc%d",
 269                              (l >> OP_SH_BCC) & OP_MASK_BCC);
 270       break;
 271
 272     case 'M':
 273       (*info->fprintf_func) (info->stream, "$fcc%d",
 274                              (l >> OP_SH_CCC) & OP_MASK_CCC);
 275       break;
 276
 277     case 'P':
 278       (*info->fprintf_func) (info->stream, "%d",
 279                              (l >> OP_SH_PERFREG) & OP_MASK_PERFREG);
 280       break;
 281
 282     case 'H':
 283       (*info->fprintf_func) (info->stream, "%d",
 284                              (l >> OP_SH_SEL) & OP_MASK_SEL);
 285       break;
 286
 287     case 'O':
 288       (*info->fprintf_func) (info->stream, "%d",
 289                              (l >> OP_SH_ALN) & OP_MASK_ALN);
 290       break;
 291
 292     case 'Q':
 293       {
 294         unsigned int vsel = (l >> OP_SH_VSEL) & OP_MASK_VSEL;
 295         if ((vsel & 0x10) == 0)
 296           {
 297             int fmt;
 298             vsel &= 0x0f;
 299             for (fmt = 0; fmt < 3; fmt++, vsel >>= 1)
 300               if ((vsel & 1) == 0)
 301                 break;
 302             (*info->fprintf_func) (info->stream, "$v%d[%d]",
 303                                    (l >> OP_SH_FT) & OP_MASK_FT,
 304                                    vsel >> 1);
 305           }
 306         else if ((vsel & 0x08) == 0)
 307           {
 308             (*info->fprintf_func) (info->stream, "$v%d",
 309                                    (l >> OP_SH_FT) & OP_MASK_FT);
 310           }
 311         else
 312           {
 313             (*info->fprintf_func) (info->stream, "0x%x",
 314                                    (l >> OP_SH_FT) & OP_MASK_FT);
 315           }
 316       }
 317       break;
 318
 319     case 'X':
 320       (*info->fprintf_func) (info->stream, "$v%d",
 321                              (l >> OP_SH_FD) & OP_MASK_FD);
 322       break;
 323
 324     case 'Y':
 325       (*info->fprintf_func) (info->stream, "$v%d",
 326                              (l >> OP_SH_FS) & OP_MASK_FS);
 327       break;
 328
 329     case 'Z':
 330       (*info->fprintf_func) (info->stream, "$v%d",
 331                              (l >> OP_SH_FT) & OP_MASK_FT);
 332       break;
 333
 334     default:
 335       /* xgettext:c-format */
 336       (*info->fprintf_func) (info->stream,
 337                              _("# internal error, undefined modifier(%c)"),
 338                              *d);
 339       break;
 340     }
 341 }
 342 \f
 343 /* Figure out the MIPS ISA and CPU based on the machine number.  */
 344
 345 static void
 346 mips_isa_type (mach, isa, cputype)
 347      int mach;
 348      int *isa;
 349      int *cputype;
 350 {
 351   switch (mach)
 352     {
 353     case bfd_mach_mips3000:
 354       *cputype = CPU_R3000;
 355       *isa = ISA_MIPS1;
 356       break;
 357     case bfd_mach_mips3900:
 358       *cputype = CPU_R3900;
 359       *isa = ISA_MIPS1;
 360       break;
 361     case bfd_mach_mips4000:
 362       *cputype = CPU_R4000;
 363       *isa = ISA_MIPS3;
 364       break;
 365     case bfd_mach_mips4010:
 366       *cputype = CPU_R4010;
 367       *isa = ISA_MIPS2;
 368       break;
 369     case bfd_mach_mips4100:
 370       *cputype = CPU_VR4100;
 371       *isa = ISA_MIPS3;
 372       break;
 373     case bfd_mach_mips4111:
 374       *cputype = CPU_R4111;
 375       *isa = ISA_MIPS3;
 376       break;
 377     case bfd_mach_mips4300:
 378       *cputype = CPU_R4300;
 379       *isa = ISA_MIPS3;
 380       break;
 381     case bfd_mach_mips4400:
 382       *cputype = CPU_R4400;
 383       *isa = ISA_MIPS3;
 384       break;
 385     case bfd_mach_mips4600:
 386       *cputype = CPU_R4600;
 387       *isa = ISA_MIPS3;
 388       break;
 389     case bfd_mach_mips4650:
 390       *cputype = CPU_R4650;
 391       *isa = ISA_MIPS3;
 392       break;
 393     case bfd_mach_mips5000:
 394       *cputype = CPU_R5000;
 395       *isa = ISA_MIPS4;
 396       break;
 397     case bfd_mach_mips6000:
 398       *cputype = CPU_R6000;
 399       *isa = ISA_MIPS2;
 400       break;
 401     case bfd_mach_mips8000:
 402       *cputype = CPU_R8000;
 403       *isa = ISA_MIPS4;
 404       break;
 405     case bfd_mach_mips10000:
 406       *cputype = CPU_R10000;
 407       *isa = ISA_MIPS4;
 408       break;
 409     case bfd_mach_mips12000:
 410       *cputype = CPU_R12000;
 411       *isa = ISA_MIPS4;
 412       break;
 413     case bfd_mach_mips16:
 414       *cputype = CPU_MIPS16;
 415       *isa = ISA_MIPS3 | INSN_MIPS16;
 416       break;
 417     case bfd_mach_mips5:
 418       *cputype = CPU_MIPS5;
 419       *isa = ISA_MIPS5;
 420       break;
 421     case bfd_mach_mips_sb1:
 422       *cputype = CPU_SB1;
 423       *isa = ISA_MIPS64 | INSN_MIPS3D | INSN_SB1;
 424       break;
 425     case bfd_mach_mipsisa32:
 426       *cputype = CPU_MIPS32;
 427       /* For stock MIPS32, disassemble all applicable MIPS-specified ASEs.
 428          Note that MIPS-3D and MDMX are not applicable to MIPS32.  (See
 429          _MIPS32 Architecture For Programmers Volume I: Introduction to the
 430          MIPS32 Architecture_ (MIPS Document Number MD00082, Revision 0.95),
 431          page 1.  */
 432       *isa = ISA_MIPS32 | INSN_MIPS16;
 433       break;
 434     case bfd_mach_mipsisa64:
 435       *cputype = CPU_MIPS64;
 436       /* For stock MIPS64, disassemble all applicable MIPS-specified ASEs.  */
 437       *isa = ISA_MIPS64 | INSN_MIPS16 | INSN_MIPS3D | INSN_MDMX;
 438       break;
 439
 440     default:
 441       *cputype = CPU_R3000;
 442       *isa = ISA_MIPS3;
 443       break;
 444     }
 445 }
 446
 447 /* Check if the object uses NewABI conventions.  */
 448
 449 static int
 450 is_newabi (header)
 451      Elf_Internal_Ehdr *header;
 452 {
 453   /* There are no old-style ABIs which use 64-bit ELF.  */
 454   if (header->e_ident[EI_CLASS] == ELFCLASS64)
 455     return 1;
 456
 457   /* If a 32-bit ELF file, n32 is a new-style ABI.  */
 458   if ((header->e_flags & EF_MIPS_ABI2) != 0)
 459     return 1;
 460
 461   return 0;
 462 }
 463 \f
 464 /* Print the mips instruction at address MEMADDR in debugged memory,
 465    on using INFO.  Returns length of the instruction, in bytes, which is
 466    always INSNLEN.  BIGENDIAN must be 1 if this is big-endian code, 0 if
 467    this is little-endian code.  */
 468
 469 static int
 470 print_insn_mips (memaddr, word, info)
 471      bfd_vma memaddr;
 472      unsigned long int word;
 473      struct disassemble_info *info;
 474 {
 475   register const struct mips_opcode *op;
 476   int target_processor, mips_isa;
 477   static boolean init = 0;
 478   static const struct mips_opcode *mips_hash[OP_MASK_OP + 1];
 479
 480   /* Build a hash table to shorten the search time.  */
 481   if (! init)
 482     {
 483       unsigned int i;
 484
 485       for (i = 0; i <= OP_MASK_OP; i++)
 486         {
 487           for (op = mips_opcodes; op < &mips_opcodes[NUMOPCODES]; op++)
 488             {
 489               if (op->pinfo == INSN_MACRO)
 490                 continue;
 491               if (i == ((op->match >> OP_SH_OP) & OP_MASK_OP))
 492                 {
 493                   mips_hash[i] = op;
 494                   break;
 495                 }
 496             }
 497         }
 498
 499       init = 1;
 500     }
 501
 502 #if ! SYMTAB_AVAILABLE
 503   /* This is running out on a target machine, not in a host tool.
 504      FIXME: Where does mips_target_info come from?  */
 505   target_processor = mips_target_info.processor;
 506   mips_isa = mips_target_info.isa;
 507 #else
 508   mips_isa_type (info->mach, &mips_isa, &target_processor);
 509 #endif
 510
 511   info->bytes_per_chunk = INSNLEN;
 512   info->display_endian = info->endian;
 513   info->insn_info_valid = 1;
 514   info->branch_delay_insns = 0;
 515   info->data_size = 0;
 516   info->insn_type = dis_nonbranch;
 517   info->target = 0;
 518   info->target2 = 0;
 519
 520   op = mips_hash[(word >> OP_SH_OP) & OP_MASK_OP];
 521   if (op != NULL)
 522     {
 523       for (; op < &mips_opcodes[NUMOPCODES]; op++)
 524         {
 525           if (op->pinfo != INSN_MACRO && (word & op->mask) == op->match)
 526             {
 527               register const char *d;
 528
 529               if (! OPCODE_IS_MEMBER (op, mips_isa, target_processor))
 530                 continue;
 531
 532               /* Figure out instruction type and branch delay information.  */
 533               if ((op->pinfo & INSN_UNCOND_BRANCH_DELAY) != 0)
 534                 {
 535                   if ((info->insn_type & INSN_WRITE_GPR_31) != 0)
 536                     info->insn_type = dis_jsr;
 537                   else
 538                     info->insn_type = dis_branch;
 539                   info->branch_delay_insns = 1;
 540                 }
 541               else if ((op->pinfo & (INSN_COND_BRANCH_DELAY
 542                                      | INSN_COND_BRANCH_LIKELY)) != 0)
 543                 {
 544                   if ((info->insn_type & INSN_WRITE_GPR_31) != 0)
 545                     info->insn_type = dis_condjsr;
 546                   else
 547                     info->insn_type = dis_condbranch;
 548                   info->branch_delay_insns = 1;
 549                 }
 550               else if ((op->pinfo & (INSN_STORE_MEMORY
 551                                      | INSN_LOAD_MEMORY_DELAY)) != 0)
 552                 info->insn_type = dis_dref;
 553
 554               (*info->fprintf_func) (info->stream, "%s", op->name);
 555
 556               d = op->args;
 557               if (d != NULL && *d != '\0')
 558                 {
 559                   (*info->fprintf_func) (info->stream, "\t");
 560                   for (; *d != '\0'; d++)
 561                     print_insn_arg (d, word, memaddr, info);
 562                 }
 563
 564               return INSNLEN;
 565             }
 566         }
 567     }
 568
 569   /* Handle undefined instructions.  */
 570   info->insn_type = dis_noninsn;
 571   (*info->fprintf_func) (info->stream, "0x%x", word);
 572   return INSNLEN;
 573 }
 574 \f
 575 /* In an environment where we do not know the symbol type of the
 576    instruction we are forced to assume that the low order bit of the
 577    instructions' address may mark it as a mips16 instruction.  If we
 578    are single stepping, or the pc is within the disassembled function,
 579    this works.  Otherwise, we need a clue.  Sometimes.  */
 580
 581 static int
 582 _print_insn_mips (memaddr, info, endianness)
 583      bfd_vma memaddr;
 584      struct disassemble_info *info;
 585      enum bfd_endian endianness;
 586 {
 587   bfd_byte buffer[INSNLEN];
 588   int status;
 589
 590 #if 1
 591   /* FIXME: If odd address, this is CLEARLY a mips 16 instruction.  */
 592   /* Only a few tools will work this way.  */
 593   if (memaddr & 0x01)
 594     return print_insn_mips16 (memaddr, info);
 595 #endif
 596
 597 #if SYMTAB_AVAILABLE
 598   if (info->mach == 16
 599       || (info->flavour == bfd_target_elf_flavour
 600           && info->symbols != NULL
 601           && ((*(elf_symbol_type **) info->symbols)->internal_elf_sym.st_other
 602               == STO_MIPS16)))
 603     return print_insn_mips16 (memaddr, info);
 604 #endif
 605
 606   /* Use mips64_reg_names for new ABI.  */
 607   reg_names = mips32_reg_names;
 608
 609   if (info->flavour == bfd_target_elf_flavour && info->symbols != NULL)
 610     {
 611       Elf_Internal_Ehdr *header;
 612
 613       header = elf_elfheader (bfd_asymbol_bfd (*(info->symbols)));
 614       if (is_newabi (header))
 615         reg_names = mips64_reg_names;
 616     }
 617
 618   status = (*info->read_memory_func) (memaddr, buffer, INSNLEN, info);
 619   if (status == 0)
 620     {
 621       unsigned long insn;
 622
 623       if (endianness == BFD_ENDIAN_BIG)
 624         insn = (unsigned long) bfd_getb32 (buffer);
 625       else
 626         insn = (unsigned long) bfd_getl32 (buffer);
 627
 628       return print_insn_mips (memaddr, insn, info);
 629     }
 630   else
 631     {
 632       (*info->memory_error_func) (status, memaddr, info);
 633       return -1;
 634     }
 635 }
 636
 637 int
 638 print_insn_big_mips (memaddr, info)
 639      bfd_vma memaddr;
 640      struct disassemble_info *info;
 641 {
 642   return _print_insn_mips (memaddr, info, BFD_ENDIAN_BIG);
 643 }
 644
 645 int
 646 print_insn_little_mips (memaddr, info)
 647      bfd_vma memaddr;
 648      struct disassemble_info *info;
 649 {
 650   return _print_insn_mips (memaddr, info, BFD_ENDIAN_LITTLE);
 651 }
 652 \f
 653 /* Disassemble mips16 instructions.  */
 654
 655 static int
 656 print_insn_mips16 (memaddr, info)
 657      bfd_vma memaddr;
 658      struct disassemble_info *info;
 659 {
 660   int status;
 661   bfd_byte buffer[2];
 662   int length;
 663   int insn;
 664   boolean use_extend;
 665   int extend = 0;
 666   const struct mips_opcode *op, *opend;
 667
 668   info->bytes_per_chunk = 2;
 669   info->display_endian = info->endian;
 670   info->insn_info_valid = 1;
 671   info->branch_delay_insns = 0;
 672   info->data_size = 0;
 673   info->insn_type = dis_nonbranch;
 674   info->target = 0;
 675   info->target2 = 0;
 676
 677   status = (*info->read_memory_func) (memaddr, buffer, 2, info);
 678   if (status != 0)
 679     {
 680       (*info->memory_error_func) (status, memaddr, info);
 681       return -1;
 682     }
 683
 684   length = 2;
 685
 686   if (info->endian == BFD_ENDIAN_BIG)
 687     insn = bfd_getb16 (buffer);
 688   else
 689     insn = bfd_getl16 (buffer);
 690
 691   /* Handle the extend opcode specially.  */
 692   use_extend = false;
 693   if ((insn & 0xf800) == 0xf000)
 694     {
 695       use_extend = true;
 696       extend = insn & 0x7ff;
 697
 698       memaddr += 2;
 699
 700       status = (*info->read_memory_func) (memaddr, buffer, 2, info);
 701       if (status != 0)
 702         {
 703           (*info->fprintf_func) (info->stream, "extend 0x%x",
 704                                  (unsigned int) extend);
 705           (*info->memory_error_func) (status, memaddr, info);
 706           return -1;
 707         }
 708
 709       if (info->endian == BFD_ENDIAN_BIG)
 710         insn = bfd_getb16 (buffer);
 711       else
 712         insn = bfd_getl16 (buffer);
 713
 714       /* Check for an extend opcode followed by an extend opcode.  */
 715       if ((insn & 0xf800) == 0xf000)
 716         {
 717           (*info->fprintf_func) (info->stream, "extend 0x%x",
 718                                  (unsigned int) extend);
 719           info->insn_type = dis_noninsn;
 720           return length;
 721         }
 722
 723       length += 2;
 724     }
 725
 726   /* FIXME: Should probably use a hash table on the major opcode here.  */
 727
 728   opend = mips16_opcodes + bfd_mips16_num_opcodes;
 729   for (op = mips16_opcodes; op < opend; op++)
 730     {
 731       if (op->pinfo != INSN_MACRO && (insn & op->mask) == op->match)
 732         {
 733           const char *s;
 734
 735           if (strchr (op->args, 'a') != NULL)
 736             {
 737               if (use_extend)
 738                 {
 739                   (*info->fprintf_func) (info->stream, "extend 0x%x",
 740                                          (unsigned int) extend);
 741                   info->insn_type = dis_noninsn;
 742                   return length - 2;
 743                 }
 744
 745               use_extend = false;
 746
 747               memaddr += 2;
 748
 749               status = (*info->read_memory_func) (memaddr, buffer, 2,
 750                                                   info);
 751               if (status == 0)
 752                 {
 753                   use_extend = true;
 754                   if (info->endian == BFD_ENDIAN_BIG)
 755                     extend = bfd_getb16 (buffer);
 756                   else
 757                     extend = bfd_getl16 (buffer);
 758                   length += 2;
 759                 }
 760             }
 761
 762           (*info->fprintf_func) (info->stream, "%s", op->name);
 763           if (op->args[0] != '\0')
 764             (*info->fprintf_func) (info->stream, "\t");
 765
 766           for (s = op->args; *s != '\0'; s++)
 767             {
 768               if (*s == ','
 769                   && s[1] == 'w'
 770                   && (((insn >> MIPS16OP_SH_RX) & MIPS16OP_MASK_RX)
 771                       == ((insn >> MIPS16OP_SH_RY) & MIPS16OP_MASK_RY)))
 772                 {
 773                   /* Skip the register and the comma.  */
 774                   ++s;
 775                   continue;
 776                 }
 777               if (*s == ','
 778                   && s[1] == 'v'
 779                   && (((insn >> MIPS16OP_SH_RZ) & MIPS16OP_MASK_RZ)
 780                       == ((insn >> MIPS16OP_SH_RX) & MIPS16OP_MASK_RX)))
 781                 {
 782                   /* Skip the register and the comma.  */
 783                   ++s;
 784                   continue;
 785                 }
 786               print_mips16_insn_arg (*s, op, insn, use_extend, extend, memaddr,
 787                                      info);
 788             }
 789
 790           if ((op->pinfo & INSN_UNCOND_BRANCH_DELAY) != 0)
 791             {
 792               info->branch_delay_insns = 1;
 793               if (info->insn_type != dis_jsr)
 794                 info->insn_type = dis_branch;
 795             }
 796
 797           return length;
 798         }
 799     }
 800
 801   if (use_extend)
 802     (*info->fprintf_func) (info->stream, "0x%x", extend | 0xf000);
 803   (*info->fprintf_func) (info->stream, "0x%x", insn);
 804   info->insn_type = dis_noninsn;
 805
 806   return length;
 807 }
 808
 809 /* Disassemble an operand for a mips16 instruction.  */
 810
 811 static void
 812 print_mips16_insn_arg (type, op, l, use_extend, extend, memaddr, info)
 813      char type;
 814      const struct mips_opcode *op;
 815      int l;
 816      boolean use_extend;
 817      int extend;
 818      bfd_vma memaddr;
 819      struct disassemble_info *info;
 820 {
 821   switch (type)
 822     {
 823     case ',':
 824     case '(':
 825     case ')':
 826       (*info->fprintf_func) (info->stream, "%c", type);
 827       break;
 828
 829     case 'y':
 830     case 'w':
 831       (*info->fprintf_func) (info->stream, "%s",
 832                              mips16_reg_names[((l >> MIPS16OP_SH_RY)
 833                                                & MIPS16OP_MASK_RY)]);
 834       break;
 835
 836     case 'x':
 837     case 'v':
 838       (*info->fprintf_func) (info->stream, "%s",
 839                              mips16_reg_names[((l >> MIPS16OP_SH_RX)
 840                                                & MIPS16OP_MASK_RX)]);
 841       break;
 842
 843     case 'z':
 844       (*info->fprintf_func) (info->stream, "%s",
 845                              mips16_reg_names[((l >> MIPS16OP_SH_RZ)
 846                                                & MIPS16OP_MASK_RZ)]);
 847       break;
 848
 849     case 'Z':
 850       (*info->fprintf_func) (info->stream, "%s",
 851                              mips16_reg_names[((l >> MIPS16OP_SH_MOVE32Z)
 852                                                & MIPS16OP_MASK_MOVE32Z)]);
 853       break;
 854
 855     case '0':
 856       (*info->fprintf_func) (info->stream, "%s", mips32_reg_names[0]);
 857       break;
 858
 859     case 'S':
 860       (*info->fprintf_func) (info->stream, "%s", mips32_reg_names[29]);
 861       break;
 862
 863     case 'P':
 864       (*info->fprintf_func) (info->stream, "$pc");
 865       break;
 866
 867     case 'R':
 868       (*info->fprintf_func) (info->stream, "%s", mips32_reg_names[31]);
 869       break;
 870
 871     case 'X':
 872       (*info->fprintf_func) (info->stream, "%s",
 873                              mips32_reg_names[((l >> MIPS16OP_SH_REGR32)
 874                                                & MIPS16OP_MASK_REGR32)]);
 875       break;
 876
 877     case 'Y':
 878       (*info->fprintf_func) (info->stream, "%s",
 879                              mips32_reg_names[MIPS16OP_EXTRACT_REG32R (l)]);
 880       break;
 881
 882     case '<':
 883     case '>':
 884     case '[':
 885     case ']':
 886     case '4':
 887     case '5':
 888     case 'H':
 889     case 'W':
 890     case 'D':
 891     case 'j':
 892     case '6':
 893     case '8':
 894     case 'V':
 895     case 'C':
 896     case 'U':
 897     case 'k':
 898     case 'K':
 899     case 'p':
 900     case 'q':
 901     case 'A':
 902     case 'B':
 903     case 'E':
 904       {
 905         int immed, nbits, shift, signedp, extbits, pcrel, extu, branch;
 906
 907         shift = 0;
 908         signedp = 0;
 909         extbits = 16;
 910         pcrel = 0;
 911         extu = 0;
 912         branch = 0;
 913         switch (type)
 914           {
 915           case '<':
 916             nbits = 3;
 917             immed = (l >> MIPS16OP_SH_RZ) & MIPS16OP_MASK_RZ;
 918             extbits = 5;
 919             extu = 1;
 920             break;
 921           case '>':
 922             nbits = 3;
 923             immed = (l >> MIPS16OP_SH_RX) & MIPS16OP_MASK_RX;
 924             extbits = 5;
 925             extu = 1;
 926             break;
 927           case '[':
 928             nbits = 3;
 929             immed = (l >> MIPS16OP_SH_RZ) & MIPS16OP_MASK_RZ;
 930             extbits = 6;
 931             extu = 1;
 932             break;
 933           case ']':
 934             nbits = 3;
 935             immed = (l >> MIPS16OP_SH_RX) & MIPS16OP_MASK_RX;
 936             extbits = 6;
 937             extu = 1;
 938             break;
 939           case '4':
 940             nbits = 4;
 941             immed = (l >> MIPS16OP_SH_IMM4) & MIPS16OP_MASK_IMM4;
 942             signedp = 1;
 943             extbits = 15;
 944             break;
 945           case '5':
 946             nbits = 5;
 947             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
 948             info->insn_type = dis_dref;
 949             info->data_size = 1;
 950             break;
 951           case 'H':
 952             nbits = 5;
 953             shift = 1;
 954             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
 955             info->insn_type = dis_dref;
 956             info->data_size = 2;
 957             break;
 958           case 'W':
 959             nbits = 5;
 960             shift = 2;
 961             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
 962             if ((op->pinfo & MIPS16_INSN_READ_PC) == 0
 963                 && (op->pinfo & MIPS16_INSN_READ_SP) == 0)
 964               {
 965                 info->insn_type = dis_dref;
 966                 info->data_size = 4;
 967               }
 968             break;
 969           case 'D':
 970             nbits = 5;
 971             shift = 3;
 972             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
 973             info->insn_type = dis_dref;
 974             info->data_size = 8;
 975             break;
 976           case 'j':
 977             nbits = 5;
 978             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
 979             signedp = 1;
 980             break;
 981           case '6':
 982             nbits = 6;
 983             immed = (l >> MIPS16OP_SH_IMM6) & MIPS16OP_MASK_IMM6;
 984             break;
 985           case '8':
 986             nbits = 8;
 987             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
 988             break;
 989           case 'V':
 990             nbits = 8;
 991             shift = 2;
 992             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
 993             /* FIXME: This might be lw, or it might be addiu to $sp or
 994                $pc.  We assume it's load.  */
 995             info->insn_type = dis_dref;
 996             info->data_size = 4;
 997             break;
 998           case 'C':
 999             nbits = 8;
1000             shift = 3;
1001             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1002             info->insn_type = dis_dref;
1003             info->data_size = 8;
1004             break;
1005           case 'U':
1006             nbits = 8;
1007             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1008             extu = 1;
1009             break;
1010           case 'k':
1011             nbits = 8;
1012             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1013             signedp = 1;
1014             break;
1015           case 'K':
1016             nbits = 8;
1017             shift = 3;
1018             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1019             signedp = 1;
1020             break;
1021           case 'p':
1022             nbits = 8;
1023             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1024             signedp = 1;
1025             pcrel = 1;
1026             branch = 1;
1027             info->insn_type = dis_condbranch;
1028             break;
1029           case 'q':
1030             nbits = 11;
1031             immed = (l >> MIPS16OP_SH_IMM11) & MIPS16OP_MASK_IMM11;
1032             signedp = 1;
1033             pcrel = 1;
1034             branch = 1;
1035             info->insn_type = dis_branch;
1036             break;
1037           case 'A':
1038             nbits = 8;
1039             shift = 2;
1040             immed = (l >> MIPS16OP_SH_IMM8) & MIPS16OP_MASK_IMM8;
1041             pcrel = 1;
1042             /* FIXME: This can be lw or la.  We assume it is lw.  */
1043             info->insn_type = dis_dref;
1044             info->data_size = 4;
1045             break;
1046           case 'B':
1047             nbits = 5;
1048             shift = 3;
1049             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
1050             pcrel = 1;
1051             info->insn_type = dis_dref;
1052             info->data_size = 8;
1053             break;
1054           case 'E':
1055             nbits = 5;
1056             shift = 2;
1057             immed = (l >> MIPS16OP_SH_IMM5) & MIPS16OP_MASK_IMM5;
1058             pcrel = 1;
1059             break;
1060           default:
1061             abort ();
1062           }
1063
1064         if (! use_extend)
1065           {
1066             if (signedp && immed >= (1 << (nbits - 1)))
1067               immed -= 1 << nbits;
1068             immed <<= shift;
1069             if ((type == '<' || type == '>' || type == '[' || type == ']')
1070                 && immed == 0)
1071               immed = 8;
1072           }
1073         else
1074           {
1075             if (extbits == 16)
1076               immed |= ((extend & 0x1f) << 11) | (extend & 0x7e0);
1077             else if (extbits == 15)
1078               immed |= ((extend & 0xf) << 11) | (extend & 0x7f0);
1079             else
1080               immed = ((extend >> 6) & 0x1f) | (extend & 0x20);
1081             immed &= (1 << extbits) - 1;
1082             if (! extu && immed >= (1 << (extbits - 1)))
1083               immed -= 1 << extbits;
1084           }
1085
1086         if (! pcrel)
1087           (*info->fprintf_func) (info->stream, "%d", immed);
1088         else
1089           {
1090             bfd_vma baseaddr;
1091
1092             if (branch)
1093               {
1094                 immed *= 2;
1095                 baseaddr = memaddr + 2;
1096               }
1097             else if (use_extend)
1098               baseaddr = memaddr - 2;
1099             else
1100               {
1101                 int status;
1102                 bfd_byte buffer[2];
1103
1104                 baseaddr = memaddr;
1105
1106                 /* If this instruction is in the delay slot of a jr
1107                    instruction, the base address is the address of the
1108                    jr instruction.  If it is in the delay slot of jalr
1109                    instruction, the base address is the address of the
1110                    jalr instruction.  This test is unreliable: we have
1111                    no way of knowing whether the previous word is
1112                    instruction or data.  */
1113                 status = (*info->read_memory_func) (memaddr - 4, buffer, 2,
1114                                                     info);
1115                 if (status == 0
1116                     && (((info->endian == BFD_ENDIAN_BIG
1117                           ? bfd_getb16 (buffer)
1118                           : bfd_getl16 (buffer))
1119                          & 0xf800) == 0x1800))
1120                   baseaddr = memaddr - 4;
1121                 else
1122                   {
1123                     status = (*info->read_memory_func) (memaddr - 2, buffer,
1124                                                         2, info);
1125                     if (status == 0
1126                         && (((info->endian == BFD_ENDIAN_BIG
1127                               ? bfd_getb16 (buffer)
1128                               : bfd_getl16 (buffer))
1129                              & 0xf81f) == 0xe800))
1130                       baseaddr = memaddr - 2;
1131                   }
1132               }
1133             info->target = (baseaddr & ~((1 << shift) - 1)) + immed;
1134             (*info->print_address_func) (info->target, info);
1135           }
1136       }
1137       break;
1138
1139     case 'a':
1140       if (! use_extend)
1141         extend = 0;
1142       l = ((l & 0x1f) << 23) | ((l & 0x3e0) << 13) | (extend << 2);
1143       info->target = ((memaddr + 4) & ~(bfd_vma) 0x0fffffff) | l;
1144       (*info->print_address_func) (info->target, info);
1145       info->insn_type = dis_jsr;
1146       info->branch_delay_insns = 1;
1147       break;
1148
1149     case 'l':
1150     case 'L':
1151       {
1152         int need_comma, amask, smask;
1153
1154         need_comma = 0;
1155
1156         l = (l >> MIPS16OP_SH_IMM6) & MIPS16OP_MASK_IMM6;
1157
1158         amask = (l >> 3) & 7;
1159
1160         if (amask > 0 && amask < 5)
1161           {
1162             (*info->fprintf_func) (info->stream, "%s", mips32_reg_names[4]);
1163             if (amask > 1)
1164               (*info->fprintf_func) (info->stream, "-%s",
1165                                      mips32_reg_names[amask + 3]);
1166             need_comma = 1;
1167           }
1168
1169         smask = (l >> 1) & 3;
1170         if (smask == 3)
1171           {
1172             (*info->fprintf_func) (info->stream, "%s??",
1173                                    need_comma ? "," : "");
1174             need_comma = 1;
1175           }
1176         else if (smask > 0)
1177           {
1178             (*info->fprintf_func) (info->stream, "%s%s",
1179                                    need_comma ? "," : "",
1180                                    mips32_reg_names[16]);
1181             if (smask > 1)
1182               (*info->fprintf_func) (info->stream, "-%s",
1183                                      mips32_reg_names[smask + 15]);
1184             need_comma = 1;
1185           }
1186
1187         if (l & 1)
1188           {
1189             (*info->fprintf_func) (info->stream, "%s%s",
1190                                    need_comma ? "," : "",
1191                                    mips32_reg_names[31]);
1192             need_comma = 1;
1193           }
1194
1195         if (amask == 5 || amask == 6)
1196           {
1197             (*info->fprintf_func) (info->stream, "%s$f0",
1198                                    need_comma ? "," : "");
1199             if (amask == 6)
1200               (*info->fprintf_func) (info->stream, "-$f1");
1201           }
1202       }
1203       break;
1204
1205     default:
1206       /* xgettext:c-format */
1207       (*info->fprintf_func)
1208         (info->stream,
1209          _("# internal disassembler error, unrecognised modifier (%c)"),
1210          type);
1211       abort ();
1212     }
1213 }