| 1 | /* ppc-dis.c -- Disassemble PowerPC instructions |
| 2 | Copyright 1994 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, 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 20 | |
| 21 | #include <stdio.h> |
| 22 | #include "ansidecl.h" |
| 23 | #include "sysdep.h" |
| 24 | #include "dis-asm.h" |
| 25 | #include "opcode/ppc.h" |
| 26 | |
| 27 | /* This file provides several disassembler functions, all of which use |
| 28 | the disassembler interface defined in dis-asm.h. Several functions |
| 29 | are provided because this file handles disassembly for the PowerPC |
| 30 | in both big and little endian mode and also for the POWER (RS/6000) |
| 31 | chip. */ |
| 32 | |
| 33 | static int print_insn_powerpc PARAMS ((bfd_vma, struct disassemble_info *, |
| 34 | int bigendian, int dialect)); |
| 35 | |
| 36 | /* Print a big endian PowerPC instruction. */ |
| 37 | |
| 38 | int |
| 39 | print_insn_big_powerpc (memaddr, info) |
| 40 | bfd_vma memaddr; |
| 41 | struct disassemble_info *info; |
| 42 | { |
| 43 | return print_insn_powerpc (memaddr, info, 1, PPC_OPCODE_PPC); |
| 44 | } |
| 45 | |
| 46 | /* Print a little endian PowerPC instruction. */ |
| 47 | |
| 48 | int |
| 49 | print_insn_little_powerpc (memaddr, info) |
| 50 | bfd_vma memaddr; |
| 51 | struct disassemble_info *info; |
| 52 | { |
| 53 | return print_insn_powerpc (memaddr, info, 0, PPC_OPCODE_PPC); |
| 54 | } |
| 55 | |
| 56 | /* Print a POWER (RS/6000) instruction. */ |
| 57 | |
| 58 | int |
| 59 | print_insn_rs6000 (memaddr, info) |
| 60 | bfd_vma memaddr; |
| 61 | struct disassemble_info *info; |
| 62 | { |
| 63 | return print_insn_powerpc (memaddr, info, 1, PPC_OPCODE_POWER); |
| 64 | } |
| 65 | |
| 66 | /* Print a PowerPC or POWER instruction. */ |
| 67 | |
| 68 | static int |
| 69 | print_insn_powerpc (memaddr, info, bigendian, dialect) |
| 70 | bfd_vma memaddr; |
| 71 | struct disassemble_info *info; |
| 72 | int bigendian; |
| 73 | int dialect; |
| 74 | { |
| 75 | bfd_byte buffer[4]; |
| 76 | int status; |
| 77 | unsigned long insn; |
| 78 | const struct powerpc_opcode *opcode; |
| 79 | const struct powerpc_opcode *opcode_end; |
| 80 | unsigned long op; |
| 81 | |
| 82 | status = (*info->read_memory_func) (memaddr, buffer, 4, info); |
| 83 | if (status != 0) |
| 84 | { |
| 85 | (*info->memory_error_func) (status, memaddr, info); |
| 86 | return -1; |
| 87 | } |
| 88 | |
| 89 | if (bigendian) |
| 90 | insn = bfd_getb32 (buffer); |
| 91 | else |
| 92 | insn = bfd_getl32 (buffer); |
| 93 | |
| 94 | /* Get the major opcode of the instruction. */ |
| 95 | op = PPC_OP (insn); |
| 96 | |
| 97 | /* Find the first match in the opcode table. We could speed this up |
| 98 | a bit by doing a binary search on the major opcode. */ |
| 99 | opcode_end = powerpc_opcodes + powerpc_num_opcodes; |
| 100 | for (opcode = powerpc_opcodes; opcode < opcode_end; opcode++) |
| 101 | { |
| 102 | unsigned long table_op; |
| 103 | const unsigned char *opindex; |
| 104 | const struct powerpc_operand *operand; |
| 105 | int invalid; |
| 106 | int need_comma; |
| 107 | int need_paren; |
| 108 | |
| 109 | table_op = PPC_OP (opcode->opcode); |
| 110 | if (op < table_op) |
| 111 | break; |
| 112 | if (op > table_op) |
| 113 | continue; |
| 114 | |
| 115 | if ((insn & opcode->mask) != opcode->opcode |
| 116 | || (opcode->flags & dialect) == 0) |
| 117 | continue; |
| 118 | |
| 119 | /* Make two passes over the operands. First see if any of them |
| 120 | have extraction functions, and, if they do, make sure the |
| 121 | instruction is valid. */ |
| 122 | invalid = 0; |
| 123 | for (opindex = opcode->operands; *opindex != 0; opindex++) |
| 124 | { |
| 125 | operand = powerpc_operands + *opindex; |
| 126 | if (operand->extract) |
| 127 | (*operand->extract) (insn, &invalid); |
| 128 | } |
| 129 | if (invalid) |
| 130 | continue; |
| 131 | |
| 132 | /* The instruction is valid. */ |
| 133 | (*info->fprintf_func) (info->stream, "%s", opcode->name); |
| 134 | if (opcode->operands[0] != 0) |
| 135 | (*info->fprintf_func) (info->stream, "\t"); |
| 136 | |
| 137 | /* Now extract and print the operands. */ |
| 138 | need_comma = 0; |
| 139 | need_paren = 0; |
| 140 | for (opindex = opcode->operands; *opindex != 0; opindex++) |
| 141 | { |
| 142 | long value; |
| 143 | |
| 144 | operand = powerpc_operands + *opindex; |
| 145 | |
| 146 | /* Operands that are marked FAKE are simply ignored. We |
| 147 | already made sure that the extract function considered |
| 148 | the instruction to be valid. */ |
| 149 | if ((operand->flags & PPC_OPERAND_FAKE) != 0) |
| 150 | continue; |
| 151 | |
| 152 | /* Extract the value from the instruction. */ |
| 153 | if (operand->extract) |
| 154 | value = (*operand->extract) (insn, (int *) NULL); |
| 155 | else |
| 156 | { |
| 157 | value = (insn >> operand->shift) & ((1 << operand->bits) - 1); |
| 158 | if (operand->signedp |
| 159 | && (value & (1 << (operand->bits - 1))) != 0) |
| 160 | value -= 1 << operand->bits; |
| 161 | } |
| 162 | |
| 163 | /* If the operand is optional, and the value is zero, don't |
| 164 | print anything. */ |
| 165 | if ((operand->flags & PPC_OPERAND_OPTIONAL) != 0 |
| 166 | && (operand->flags & PPC_OPERAND_NEXT) == 0 |
| 167 | && value == 0) |
| 168 | continue; |
| 169 | |
| 170 | if (need_comma) |
| 171 | { |
| 172 | (*info->fprintf_func) (info->stream, ","); |
| 173 | need_comma = 0; |
| 174 | } |
| 175 | |
| 176 | /* Print the operand as directed by the flags. */ |
| 177 | if ((operand->flags & PPC_OPERAND_GPR) != 0) |
| 178 | (*info->fprintf_func) (info->stream, "r%ld", value); |
| 179 | else if ((operand->flags & PPC_OPERAND_FPR) != 0) |
| 180 | (*info->fprintf_func) (info->stream, "f%ld", value); |
| 181 | else if ((operand->flags & PPC_OPERAND_RELATIVE) != 0) |
| 182 | (*info->print_address_func) (memaddr + value, info); |
| 183 | else if ((operand->flags & PPC_OPERAND_ABSOLUTE) != 0) |
| 184 | (*info->print_address_func) ((bfd_vma) value & 0xffffffff, info); |
| 185 | else if ((operand->flags & PPC_OPERAND_CR) == 0 |
| 186 | || (dialect & PPC_OPCODE_PPC) == 0) |
| 187 | (*info->fprintf_func) (info->stream, "%ld", value); |
| 188 | else |
| 189 | { |
| 190 | if (operand->bits == 3) |
| 191 | (*info->fprintf_func) (info->stream, "cr%d", value); |
| 192 | else |
| 193 | { |
| 194 | static const char *cbnames[4] = { "lt", "gt", "eq", "so" }; |
| 195 | int cr; |
| 196 | int cc; |
| 197 | |
| 198 | cr = value >> 2; |
| 199 | if (cr != 0) |
| 200 | (*info->fprintf_func) (info->stream, "4*cr%d", cr); |
| 201 | cc = value & 3; |
| 202 | if (cc != 0) |
| 203 | { |
| 204 | if (cr != 0) |
| 205 | (*info->fprintf_func) (info->stream, "+"); |
| 206 | (*info->fprintf_func) (info->stream, "%s", cbnames[cc]); |
| 207 | } |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | if (need_paren) |
| 212 | { |
| 213 | (*info->fprintf_func) (info->stream, ")"); |
| 214 | need_paren = 0; |
| 215 | } |
| 216 | |
| 217 | if ((operand->flags & PPC_OPERAND_PARENS) == 0) |
| 218 | need_comma = 1; |
| 219 | else |
| 220 | { |
| 221 | (*info->fprintf_func) (info->stream, "("); |
| 222 | need_paren = 1; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | /* We have found and printed an instruction; return. */ |
| 227 | return 4; |
| 228 | } |
| 229 | |
| 230 | /* We could not find a match. */ |
| 231 | (*info->fprintf_func) (info->stream, "0x%lx", insn); |
| 232 | |
| 233 | return 4; |
| 234 | } |