opcodes/ppc-dis.c

   1 /* ppc-dis.c -- Disassemble PowerPC instructions
   2    Copyright 1994, 1995, 2000 Free Software Foundation, Inc.
   3    Written by Ian Lance Taylor, Cygnus Support
   4
   5 This file is part of GDB, GAS, and the GNU binutils.
   6
   7 GDB, GAS, and the GNU binutils are free software; you can redistribute
   8 them and/or modify them under the terms of the GNU General Public
   9 License as published by the Free Software Foundation; either version
  10 2, or (at your option) any later version.
  11
  12 GDB, GAS, and the GNU binutils are distributed in the hope that they
  13 will be useful, but WITHOUT ANY WARRANTY; without even the implied
  14 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  15 the GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this file; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 #include <stdio.h>
  22 #include "sysdep.h"
  23 #include "dis-asm.h"
  24 #include "opcode/ppc.h"
  25
  26 /* This file provides several disassembler functions, all of which use
  27    the disassembler interface defined in dis-asm.h.  Several functions
  28    are provided because this file handles disassembly for the PowerPC
  29    in both big and little endian mode and also for the POWER (RS/6000)
  30    chip.  */
  31
  32 static int print_insn_powerpc PARAMS ((bfd_vma, struct disassemble_info *,
  33                                        int bigendian, int dialect));
  34
  35 static int powerpc_dialect PARAMS ((struct disassemble_info *));
  36
  37 /* Determine which set of machines to disassemble for.  PPC403/601 or
  38    BookE.  For convenience, also disassemble instructions supported
  39    by the AltiVec vector unit.  */
  40
  41 int
  42 powerpc_dialect(info)
  43      struct disassemble_info *info;
  44 {
  45   int dialect = PPC_OPCODE_PPC | PPC_OPCODE_ALTIVEC;
  46
  47   if (BFD_DEFAULT_TARGET_SIZE == 64)
  48     dialect |= PPC_OPCODE_64;
  49
  50   if (info->disassembler_options
  51       && (strcmp (info->disassembler_options, "booke") == 0
  52           || strcmp (info->disassembler_options, "booke32") == 0
  53           || strcmp (info->disassembler_options, "booke64") == 0))
  54     dialect |= PPC_OPCODE_BOOKE | PPC_OPCODE_BOOKE64;
  55   else
  56     dialect |= PPC_OPCODE_403 | PPC_OPCODE_601;
  57
  58   if (info->disassembler_options)
  59     {
  60       if (strstr (info->disassembler_options, "32") != NULL)
  61         dialect &= ~PPC_OPCODE_64;
  62       else if (strstr (info->disassembler_options, "64") != NULL)
  63         dialect |= PPC_OPCODE_64;
  64     }
  65
  66   return dialect;
  67 }
  68
  69 /* Print a big endian PowerPC instruction.  */
  70
  71 int
  72 print_insn_big_powerpc (memaddr, info)
  73      bfd_vma memaddr;
  74      struct disassemble_info *info;
  75 {
  76   return print_insn_powerpc (memaddr, info, 1, powerpc_dialect(info));
  77 }
  78
  79 /* Print a little endian PowerPC instruction.  */
  80
  81 int
  82 print_insn_little_powerpc (memaddr, info)
  83      bfd_vma memaddr;
  84      struct disassemble_info *info;
  85 {
  86   return print_insn_powerpc (memaddr, info, 0, powerpc_dialect(info));
  87 }
  88
  89 /* Print a POWER (RS/6000) instruction.  */
  90
  91 int
  92 print_insn_rs6000 (memaddr, info)
  93      bfd_vma memaddr;
  94      struct disassemble_info *info;
  95 {
  96   return print_insn_powerpc (memaddr, info, 1, PPC_OPCODE_POWER);
  97 }
  98
  99 /* Print a PowerPC or POWER instruction.  */
 100
 101 static int
 102 print_insn_powerpc (memaddr, info, bigendian, dialect)
 103      bfd_vma memaddr;
 104      struct disassemble_info *info;
 105      int bigendian;
 106      int dialect;
 107 {
 108   bfd_byte buffer[4];
 109   int status;
 110   unsigned long insn;
 111   const struct powerpc_opcode *opcode;
 112   const struct powerpc_opcode *opcode_end;
 113   unsigned long op;
 114
 115   status = (*info->read_memory_func) (memaddr, buffer, 4, info);
 116   if (status != 0)
 117     {
 118       (*info->memory_error_func) (status, memaddr, info);
 119       return -1;
 120     }
 121
 122   if (bigendian)
 123     insn = bfd_getb32 (buffer);
 124   else
 125     insn = bfd_getl32 (buffer);
 126
 127   /* Get the major opcode of the instruction.  */
 128   op = PPC_OP (insn);
 129
 130   /* Find the first match in the opcode table.  We could speed this up
 131      a bit by doing a binary search on the major opcode.  */
 132   opcode_end = powerpc_opcodes + powerpc_num_opcodes;
 133   for (opcode = powerpc_opcodes; opcode < opcode_end; opcode++)
 134     {
 135       unsigned long table_op;
 136       const unsigned char *opindex;
 137       const struct powerpc_operand *operand;
 138       int invalid;
 139       int need_comma;
 140       int need_paren;
 141
 142       table_op = PPC_OP (opcode->opcode);
 143       if (op < table_op)
 144         break;
 145       if (op > table_op)
 146         continue;
 147
 148       if ((insn & opcode->mask) != opcode->opcode
 149           || (opcode->flags & dialect) == 0)
 150         continue;
 151
 152       /* Make two passes over the operands.  First see if any of them
 153          have extraction functions, and, if they do, make sure the
 154          instruction is valid.  */
 155       invalid = 0;
 156       for (opindex = opcode->operands; *opindex != 0; opindex++)
 157         {
 158           operand = powerpc_operands + *opindex;
 159           if (operand->extract)
 160             (*operand->extract) (insn, dialect, &invalid);
 161         }
 162       if (invalid)
 163         continue;
 164
 165       /* The instruction is valid.  */
 166       (*info->fprintf_func) (info->stream, "%s", opcode->name);
 167       if (opcode->operands[0] != 0)
 168         (*info->fprintf_func) (info->stream, "\t");
 169
 170       /* Now extract and print the operands.  */
 171       need_comma = 0;
 172       need_paren = 0;
 173       for (opindex = opcode->operands; *opindex != 0; opindex++)
 174         {
 175           long value;
 176
 177           operand = powerpc_operands + *opindex;
 178
 179           /* Operands that are marked FAKE are simply ignored.  We
 180              already made sure that the extract function considered
 181              the instruction to be valid.  */
 182           if ((operand->flags & PPC_OPERAND_FAKE) != 0)
 183             continue;
 184
 185           /* Extract the value from the instruction.  */
 186           if (operand->extract)
 187             value = (*operand->extract) (insn, dialect, (int *) NULL);
 188           else
 189             {
 190               value = (insn >> operand->shift) & ((1 << operand->bits) - 1);
 191               if ((operand->flags & PPC_OPERAND_SIGNED) != 0
 192                   && (value & (1 << (operand->bits - 1))) != 0)
 193                 value -= 1 << operand->bits;
 194             }
 195
 196           /* If the operand is optional, and the value is zero, don't
 197              print anything.  */
 198           if ((operand->flags & PPC_OPERAND_OPTIONAL) != 0
 199               && (operand->flags & PPC_OPERAND_NEXT) == 0
 200               && value == 0)
 201             continue;
 202
 203           if (need_comma)
 204             {
 205               (*info->fprintf_func) (info->stream, ",");
 206               need_comma = 0;
 207             }
 208
 209           /* Print the operand as directed by the flags.  */
 210           if ((operand->flags & PPC_OPERAND_GPR) != 0)
 211             (*info->fprintf_func) (info->stream, "r%ld", value);
 212           else if ((operand->flags & PPC_OPERAND_FPR) != 0)
 213             (*info->fprintf_func) (info->stream, "f%ld", value);
 214           else if ((operand->flags & PPC_OPERAND_VR) != 0)
 215             (*info->fprintf_func) (info->stream, "v%ld", value);
 216           else if ((operand->flags & PPC_OPERAND_RELATIVE) != 0)
 217             (*info->print_address_func) (memaddr + value, info);
 218           else if ((operand->flags & PPC_OPERAND_ABSOLUTE) != 0)
 219             (*info->print_address_func) ((bfd_vma) value & 0xffffffff, info);
 220           else if ((operand->flags & PPC_OPERAND_CR) == 0
 221                    || (dialect & PPC_OPCODE_PPC) == 0)
 222             (*info->fprintf_func) (info->stream, "%ld", value);
 223           else
 224             {
 225               if (operand->bits == 3)
 226                 (*info->fprintf_func) (info->stream, "cr%d", value);
 227               else
 228                 {
 229                   static const char *cbnames[4] = { "lt", "gt", "eq", "so" };
 230                   int cr;
 231                   int cc;
 232
 233                   cr = value >> 2;
 234                   if (cr != 0)
 235                     (*info->fprintf_func) (info->stream, "4*cr%d", cr);
 236                   cc = value & 3;
 237                   if (cc != 0)
 238                     {
 239                       if (cr != 0)
 240                         (*info->fprintf_func) (info->stream, "+");
 241                       (*info->fprintf_func) (info->stream, "%s", cbnames[cc]);
 242                     }
 243                 }
 244             }
 245
 246           if (need_paren)
 247             {
 248               (*info->fprintf_func) (info->stream, ")");
 249               need_paren = 0;
 250             }
 251
 252           if ((operand->flags & PPC_OPERAND_PARENS) == 0)
 253             need_comma = 1;
 254           else
 255             {
 256               (*info->fprintf_func) (info->stream, "(");
 257               need_paren = 1;
 258             }
 259         }
 260
 261       /* We have found and printed an instruction; return.  */
 262       return 4;
 263     }
 264
 265   /* We could not find a match.  */
 266   (*info->fprintf_func) (info->stream, ".long 0x%lx", insn);
 267
 268   return 4;
 269 }