| 1 | /* Altera Nios II disassemble routines |
| 2 | Copyright (C) 2012-2015 Free Software Foundation, Inc. |
| 3 | Contributed by Nigel Gray (ngray@altera.com). |
| 4 | Contributed by Mentor Graphics, Inc. |
| 5 | |
| 6 | This file is part of the GNU opcodes library. |
| 7 | |
| 8 | This library is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3, or (at your option) |
| 11 | any later version. |
| 12 | |
| 13 | It is distributed in the hope that it will be useful, but WITHOUT |
| 14 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| 15 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public |
| 16 | License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this file; see the file COPYING. If not, write to the |
| 20 | Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston, |
| 21 | MA 02110-1301, USA. */ |
| 22 | |
| 23 | #include "sysdep.h" |
| 24 | #include "dis-asm.h" |
| 25 | #include "opcode/nios2.h" |
| 26 | #include "libiberty.h" |
| 27 | #include <string.h> |
| 28 | #include <assert.h> |
| 29 | |
| 30 | /* No 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 | #if !defined(EMBEDDED_ENV) |
| 33 | #define SYMTAB_AVAILABLE 1 |
| 34 | #include "elf-bfd.h" |
| 35 | #include "elf/nios2.h" |
| 36 | #endif |
| 37 | |
| 38 | /* Default length of Nios II instruction in bytes. */ |
| 39 | #define INSNLEN 4 |
| 40 | |
| 41 | /* Data structures used by the opcode hash table. */ |
| 42 | typedef struct _nios2_opcode_hash |
| 43 | { |
| 44 | const struct nios2_opcode *opcode; |
| 45 | struct _nios2_opcode_hash *next; |
| 46 | } nios2_opcode_hash; |
| 47 | |
| 48 | /* Hash table size. */ |
| 49 | #define OPCODE_HASH_SIZE (IW_R1_OP_UNSHIFTED_MASK + 1) |
| 50 | |
| 51 | /* Extract the opcode from an instruction word. */ |
| 52 | static unsigned int |
| 53 | nios2_r1_extract_opcode (unsigned int x) |
| 54 | { |
| 55 | return GET_IW_R1_OP (x); |
| 56 | } |
| 57 | |
| 58 | /* Pseudo-ops are stored in a different table than regular instructions. */ |
| 59 | |
| 60 | typedef struct _nios2_disassembler_state |
| 61 | { |
| 62 | const struct nios2_opcode *opcodes; |
| 63 | const int *num_opcodes; |
| 64 | unsigned int (*extract_opcode) (unsigned int); |
| 65 | nios2_opcode_hash *hash[OPCODE_HASH_SIZE]; |
| 66 | nios2_opcode_hash *ps_hash[OPCODE_HASH_SIZE]; |
| 67 | const struct nios2_opcode *nop; |
| 68 | bfd_boolean init; |
| 69 | } nios2_disassembler_state; |
| 70 | |
| 71 | static nios2_disassembler_state |
| 72 | nios2_r1_disassembler_state = { |
| 73 | nios2_r1_opcodes, |
| 74 | &nios2_num_r1_opcodes, |
| 75 | nios2_r1_extract_opcode, |
| 76 | {}, |
| 77 | {}, |
| 78 | NULL, |
| 79 | 0 |
| 80 | }; |
| 81 | |
| 82 | /* Function to initialize the opcode hash table. */ |
| 83 | static void |
| 84 | nios2_init_opcode_hash (nios2_disassembler_state *state) |
| 85 | { |
| 86 | unsigned int i; |
| 87 | register const struct nios2_opcode *op; |
| 88 | |
| 89 | for (i = 0; i < OPCODE_HASH_SIZE; i++) |
| 90 | for (op = state->opcodes; op < &state->opcodes[*(state->num_opcodes)]; op++) |
| 91 | { |
| 92 | nios2_opcode_hash *new_hash; |
| 93 | nios2_opcode_hash **bucket = NULL; |
| 94 | |
| 95 | if ((op->pinfo & NIOS2_INSN_MACRO) == NIOS2_INSN_MACRO) |
| 96 | { |
| 97 | if (i == state->extract_opcode (op->match) |
| 98 | && (op->pinfo & (NIOS2_INSN_MACRO_MOV | NIOS2_INSN_MACRO_MOVI) |
| 99 | & 0x7fffffff)) |
| 100 | { |
| 101 | bucket = &(state->ps_hash[i]); |
| 102 | if (strcmp (op->name, "nop") == 0) |
| 103 | state->nop = op; |
| 104 | } |
| 105 | } |
| 106 | else if (i == state->extract_opcode (op->match)) |
| 107 | bucket = &(state->hash[i]); |
| 108 | |
| 109 | if (bucket) |
| 110 | { |
| 111 | new_hash = |
| 112 | (nios2_opcode_hash *) malloc (sizeof (nios2_opcode_hash)); |
| 113 | if (new_hash == NULL) |
| 114 | { |
| 115 | fprintf (stderr, |
| 116 | "error allocating memory...broken disassembler\n"); |
| 117 | abort (); |
| 118 | } |
| 119 | new_hash->opcode = op; |
| 120 | new_hash->next = NULL; |
| 121 | while (*bucket) |
| 122 | bucket = &((*bucket)->next); |
| 123 | *bucket = new_hash; |
| 124 | } |
| 125 | } |
| 126 | state->init = 1; |
| 127 | |
| 128 | #ifdef DEBUG_HASHTABLE |
| 129 | for (i = 0; i < OPCODE_HASH_SIZE; ++i) |
| 130 | { |
| 131 | nios2_opcode_hash *tmp_hash = state->hash[i]; |
| 132 | printf ("index: 0x%02X ops: ", i); |
| 133 | while (tmp_hash != NULL) |
| 134 | { |
| 135 | printf ("%s ", tmp_hash->opcode->name); |
| 136 | tmp_hash = tmp_hash->next; |
| 137 | } |
| 138 | printf ("\n"); |
| 139 | } |
| 140 | |
| 141 | for (i = 0; i < OPCODE_HASH_SIZE; ++i) |
| 142 | { |
| 143 | nios2_opcode_hash *tmp_hash = state->ps_hash[i]; |
| 144 | printf ("index: 0x%02X ops: ", i); |
| 145 | while (tmp_hash != NULL) |
| 146 | { |
| 147 | printf ("%s ", tmp_hash->opcode->name); |
| 148 | tmp_hash = tmp_hash->next; |
| 149 | } |
| 150 | printf ("\n"); |
| 151 | } |
| 152 | #endif /* DEBUG_HASHTABLE */ |
| 153 | } |
| 154 | |
| 155 | /* Return a pointer to an nios2_opcode struct for a given instruction |
| 156 | word OPCODE for bfd machine MACH, or NULL if there is an error. */ |
| 157 | const struct nios2_opcode * |
| 158 | nios2_find_opcode_hash (unsigned long opcode, |
| 159 | unsigned long mach ATTRIBUTE_UNUSED) |
| 160 | { |
| 161 | nios2_opcode_hash *entry; |
| 162 | nios2_disassembler_state *state; |
| 163 | |
| 164 | state = &nios2_r1_disassembler_state; |
| 165 | |
| 166 | /* Build a hash table to shorten the search time. */ |
| 167 | if (!state->init) |
| 168 | nios2_init_opcode_hash (state); |
| 169 | |
| 170 | /* Check for NOP first. Both NOP and MOV are macros that expand into |
| 171 | an ADD instruction, and we always want to give priority to NOP. */ |
| 172 | if (state->nop->match == (opcode & state->nop->mask)) |
| 173 | return state->nop; |
| 174 | |
| 175 | /* First look in the pseudo-op hashtable. */ |
| 176 | for (entry = state->ps_hash[state->extract_opcode (opcode)]; |
| 177 | entry; entry = entry->next) |
| 178 | if (entry->opcode->match == (opcode & entry->opcode->mask)) |
| 179 | return entry->opcode; |
| 180 | |
| 181 | /* Otherwise look in the main hashtable. */ |
| 182 | for (entry = state->hash[state->extract_opcode (opcode)]; |
| 183 | entry; entry = entry->next) |
| 184 | if (entry->opcode->match == (opcode & entry->opcode->mask)) |
| 185 | return entry->opcode; |
| 186 | |
| 187 | return NULL; |
| 188 | } |
| 189 | |
| 190 | /* There are 32 regular registers, 32 coprocessor registers, |
| 191 | and 32 control registers. */ |
| 192 | #define NUMREGNAMES 32 |
| 193 | |
| 194 | /* Return a pointer to the base of the coprocessor register name array. */ |
| 195 | static struct nios2_reg * |
| 196 | nios2_coprocessor_regs (void) |
| 197 | { |
| 198 | static struct nios2_reg *cached = NULL; |
| 199 | |
| 200 | if (!cached) |
| 201 | { |
| 202 | int i; |
| 203 | for (i = NUMREGNAMES; i < nios2_num_regs; i++) |
| 204 | if (!strcmp (nios2_regs[i].name, "c0")) |
| 205 | { |
| 206 | cached = nios2_regs + i; |
| 207 | break; |
| 208 | } |
| 209 | assert (cached); |
| 210 | } |
| 211 | return cached; |
| 212 | } |
| 213 | |
| 214 | /* Return a pointer to the base of the control register name array. */ |
| 215 | static struct nios2_reg * |
| 216 | nios2_control_regs (void) |
| 217 | { |
| 218 | static struct nios2_reg *cached = NULL; |
| 219 | |
| 220 | if (!cached) |
| 221 | { |
| 222 | int i; |
| 223 | for (i = NUMREGNAMES; i < nios2_num_regs; i++) |
| 224 | if (!strcmp (nios2_regs[i].name, "status")) |
| 225 | { |
| 226 | cached = nios2_regs + i; |
| 227 | break; |
| 228 | } |
| 229 | assert (cached); |
| 230 | } |
| 231 | return cached; |
| 232 | } |
| 233 | |
| 234 | /* Helper routine to report internal errors. */ |
| 235 | static void |
| 236 | bad_opcode (const struct nios2_opcode *op) |
| 237 | { |
| 238 | fprintf (stderr, "Internal error: broken opcode descriptor for `%s %s'\n", |
| 239 | op->name, op->args); |
| 240 | abort (); |
| 241 | } |
| 242 | |
| 243 | /* The function nios2_print_insn_arg uses the character pointed |
| 244 | to by ARGPTR to determine how it print the next token or separator |
| 245 | character in the arguments to an instruction. */ |
| 246 | static int |
| 247 | nios2_print_insn_arg (const char *argptr, |
| 248 | unsigned long opcode, bfd_vma address, |
| 249 | disassemble_info *info, |
| 250 | const struct nios2_opcode *op) |
| 251 | { |
| 252 | unsigned long i = 0; |
| 253 | struct nios2_reg *reg_base; |
| 254 | |
| 255 | switch (*argptr) |
| 256 | { |
| 257 | case ',': |
| 258 | case '(': |
| 259 | case ')': |
| 260 | (*info->fprintf_func) (info->stream, "%c", *argptr); |
| 261 | break; |
| 262 | |
| 263 | case 'd': |
| 264 | switch (op->format) |
| 265 | { |
| 266 | case iw_r_type: |
| 267 | i = GET_IW_R_C (opcode); |
| 268 | reg_base = nios2_regs; |
| 269 | break; |
| 270 | case iw_custom_type: |
| 271 | i = GET_IW_CUSTOM_C (opcode); |
| 272 | if (GET_IW_CUSTOM_READC (opcode) == 0) |
| 273 | reg_base = nios2_coprocessor_regs (); |
| 274 | else |
| 275 | reg_base = nios2_regs; |
| 276 | break; |
| 277 | default: |
| 278 | bad_opcode (op); |
| 279 | } |
| 280 | if (i < NUMREGNAMES) |
| 281 | (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| 282 | else |
| 283 | (*info->fprintf_func) (info->stream, "unknown"); |
| 284 | break; |
| 285 | |
| 286 | case 's': |
| 287 | switch (op->format) |
| 288 | { |
| 289 | case iw_r_type: |
| 290 | i = GET_IW_R_A (opcode); |
| 291 | reg_base = nios2_regs; |
| 292 | break; |
| 293 | case iw_i_type: |
| 294 | i = GET_IW_I_A (opcode); |
| 295 | reg_base = nios2_regs; |
| 296 | break; |
| 297 | case iw_custom_type: |
| 298 | i = GET_IW_CUSTOM_A (opcode); |
| 299 | if (GET_IW_CUSTOM_READA (opcode) == 0) |
| 300 | reg_base = nios2_coprocessor_regs (); |
| 301 | else |
| 302 | reg_base = nios2_regs; |
| 303 | break; |
| 304 | default: |
| 305 | bad_opcode (op); |
| 306 | } |
| 307 | if (i < NUMREGNAMES) |
| 308 | (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| 309 | else |
| 310 | (*info->fprintf_func) (info->stream, "unknown"); |
| 311 | break; |
| 312 | |
| 313 | case 't': |
| 314 | switch (op->format) |
| 315 | { |
| 316 | case iw_r_type: |
| 317 | i = GET_IW_R_B (opcode); |
| 318 | reg_base = nios2_regs; |
| 319 | break; |
| 320 | case iw_i_type: |
| 321 | i = GET_IW_I_B (opcode); |
| 322 | reg_base = nios2_regs; |
| 323 | break; |
| 324 | case iw_custom_type: |
| 325 | i = GET_IW_CUSTOM_B (opcode); |
| 326 | if (GET_IW_CUSTOM_READB (opcode) == 0) |
| 327 | reg_base = nios2_coprocessor_regs (); |
| 328 | else |
| 329 | reg_base = nios2_regs; |
| 330 | break; |
| 331 | default: |
| 332 | bad_opcode (op); |
| 333 | } |
| 334 | if (i < NUMREGNAMES) |
| 335 | (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| 336 | else |
| 337 | (*info->fprintf_func) (info->stream, "unknown"); |
| 338 | break; |
| 339 | |
| 340 | case 'i': |
| 341 | /* 16-bit signed immediate. */ |
| 342 | switch (op->format) |
| 343 | { |
| 344 | case iw_i_type: |
| 345 | i = (signed) (GET_IW_I_IMM16 (opcode) << 16) >> 16; |
| 346 | break; |
| 347 | default: |
| 348 | bad_opcode (op); |
| 349 | } |
| 350 | (*info->fprintf_func) (info->stream, "%ld", i); |
| 351 | break; |
| 352 | |
| 353 | case 'u': |
| 354 | /* 16-bit unsigned immediate. */ |
| 355 | switch (op->format) |
| 356 | { |
| 357 | case iw_i_type: |
| 358 | i = GET_IW_I_IMM16 (opcode); |
| 359 | break; |
| 360 | default: |
| 361 | bad_opcode (op); |
| 362 | } |
| 363 | (*info->fprintf_func) (info->stream, "%ld", i); |
| 364 | break; |
| 365 | |
| 366 | case 'o': |
| 367 | /* 16-bit signed immediate address offset. */ |
| 368 | switch (op->format) |
| 369 | { |
| 370 | case iw_i_type: |
| 371 | i = (signed) (GET_IW_I_IMM16 (opcode) << 16) >> 16; |
| 372 | break; |
| 373 | default: |
| 374 | bad_opcode (op); |
| 375 | } |
| 376 | address = address + 4 + i; |
| 377 | (*info->print_address_func) (address, info); |
| 378 | break; |
| 379 | |
| 380 | case 'j': |
| 381 | /* 5-bit unsigned immediate. */ |
| 382 | switch (op->format) |
| 383 | { |
| 384 | case iw_r_type: |
| 385 | i = GET_IW_R_IMM5 (opcode); |
| 386 | break; |
| 387 | default: |
| 388 | bad_opcode (op); |
| 389 | } |
| 390 | (*info->fprintf_func) (info->stream, "%ld", i); |
| 391 | break; |
| 392 | |
| 393 | case 'l': |
| 394 | /* 8-bit unsigned immediate. */ |
| 395 | switch (op->format) |
| 396 | { |
| 397 | case iw_custom_type: |
| 398 | i = GET_IW_CUSTOM_N (opcode); |
| 399 | break; |
| 400 | default: |
| 401 | bad_opcode (op); |
| 402 | } |
| 403 | (*info->fprintf_func) (info->stream, "%lu", i); |
| 404 | break; |
| 405 | |
| 406 | case 'm': |
| 407 | /* 26-bit unsigned immediate. */ |
| 408 | switch (op->format) |
| 409 | { |
| 410 | case iw_j_type: |
| 411 | i = GET_IW_J_IMM26 (opcode); |
| 412 | break; |
| 413 | default: |
| 414 | bad_opcode (op); |
| 415 | } |
| 416 | /* This translates to an address because it's only used in call |
| 417 | instructions. */ |
| 418 | address = (address & 0xf0000000) | (i << 2); |
| 419 | (*info->print_address_func) (address, info); |
| 420 | break; |
| 421 | |
| 422 | case 'c': |
| 423 | /* Control register index. */ |
| 424 | switch (op->format) |
| 425 | { |
| 426 | case iw_r_type: |
| 427 | i = GET_IW_R_IMM5 (opcode); |
| 428 | break; |
| 429 | default: |
| 430 | bad_opcode (op); |
| 431 | } |
| 432 | reg_base = nios2_control_regs (); |
| 433 | (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| 434 | break; |
| 435 | |
| 436 | default: |
| 437 | (*info->fprintf_func) (info->stream, "unknown"); |
| 438 | break; |
| 439 | } |
| 440 | return 0; |
| 441 | } |
| 442 | |
| 443 | /* nios2_disassemble does all the work of disassembling a Nios II |
| 444 | instruction opcode. */ |
| 445 | static int |
| 446 | nios2_disassemble (bfd_vma address, unsigned long opcode, |
| 447 | disassemble_info *info) |
| 448 | { |
| 449 | const struct nios2_opcode *op; |
| 450 | |
| 451 | info->bytes_per_line = INSNLEN; |
| 452 | info->bytes_per_chunk = INSNLEN; |
| 453 | info->display_endian = info->endian; |
| 454 | info->insn_info_valid = 1; |
| 455 | info->branch_delay_insns = 0; |
| 456 | info->data_size = 0; |
| 457 | info->insn_type = dis_nonbranch; |
| 458 | info->target = 0; |
| 459 | info->target2 = 0; |
| 460 | |
| 461 | /* Find the major opcode and use this to disassemble |
| 462 | the instruction and its arguments. */ |
| 463 | op = nios2_find_opcode_hash (opcode, info->mach); |
| 464 | |
| 465 | if (op != NULL) |
| 466 | { |
| 467 | const char *argstr = op->args; |
| 468 | (*info->fprintf_func) (info->stream, "%s", op->name); |
| 469 | if (argstr != NULL && *argstr != '\0') |
| 470 | { |
| 471 | (*info->fprintf_func) (info->stream, "\t"); |
| 472 | while (*argstr != '\0') |
| 473 | { |
| 474 | nios2_print_insn_arg (argstr, opcode, address, info, op); |
| 475 | ++argstr; |
| 476 | } |
| 477 | } |
| 478 | /* Tell the caller how far to advance the program counter. */ |
| 479 | info->bytes_per_chunk = op->size; |
| 480 | return op->size; |
| 481 | } |
| 482 | else |
| 483 | { |
| 484 | /* Handle undefined instructions. */ |
| 485 | info->insn_type = dis_noninsn; |
| 486 | (*info->fprintf_func) (info->stream, "0x%lx", opcode); |
| 487 | return INSNLEN; |
| 488 | } |
| 489 | } |
| 490 | |
| 491 | |
| 492 | /* print_insn_nios2 is the main disassemble function for Nios II. |
| 493 | The function diassembler(abfd) (source in disassemble.c) returns a |
| 494 | pointer to this either print_insn_big_nios2 or |
| 495 | print_insn_little_nios2, which in turn call this function when the |
| 496 | bfd machine type is Nios II. print_insn_nios2 reads the |
| 497 | instruction word at the address given, and prints the disassembled |
| 498 | instruction on the stream info->stream using info->fprintf_func. */ |
| 499 | |
| 500 | static int |
| 501 | print_insn_nios2 (bfd_vma address, disassemble_info *info, |
| 502 | enum bfd_endian endianness) |
| 503 | { |
| 504 | bfd_byte buffer[INSNLEN]; |
| 505 | int status; |
| 506 | |
| 507 | status = (*info->read_memory_func) (address, buffer, INSNLEN, info); |
| 508 | if (status == 0) |
| 509 | { |
| 510 | unsigned long insn; |
| 511 | if (endianness == BFD_ENDIAN_BIG) |
| 512 | insn = (unsigned long) bfd_getb32 (buffer); |
| 513 | else |
| 514 | insn = (unsigned long) bfd_getl32 (buffer); |
| 515 | status = nios2_disassemble (address, insn, info); |
| 516 | } |
| 517 | else |
| 518 | { |
| 519 | (*info->memory_error_func) (status, address, info); |
| 520 | status = -1; |
| 521 | } |
| 522 | return status; |
| 523 | } |
| 524 | |
| 525 | /* These two functions are the main entry points, accessed from |
| 526 | disassemble.c. */ |
| 527 | int |
| 528 | print_insn_big_nios2 (bfd_vma address, disassemble_info *info) |
| 529 | { |
| 530 | return print_insn_nios2 (address, info, BFD_ENDIAN_BIG); |
| 531 | } |
| 532 | |
| 533 | int |
| 534 | print_insn_little_nios2 (bfd_vma address, disassemble_info *info) |
| 535 | { |
| 536 | return print_insn_nios2 (address, info, BFD_ENDIAN_LITTLE); |
| 537 | } |