1 /* CGEN generic opcode support. 2 3 Copyright 1996, 1997, 1998, 1999, 2000, 2001 4 Free Software Foundation, Inc. 5 6 This file is part of the GNU Binutils and GDB, the GNU debugger. 7 8 This program 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 2, or (at your option) 11 any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License along 19 with this program; if not, write to the Free Software Foundation, Inc., 20 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 21 22 #include "sysdep.h" 23 #include <stdio.h> 24 #include "ansidecl.h" 25 #include "libiberty.h" 26 #include "safe-ctype.h" 27 #include "bfd.h" 28 #include "symcat.h" 29 #include "opcode/cgen.h" 30 31 #ifdef HAVE_ALLOCA_H 32 #include <alloca.h> 33 #endif 34 35 static unsigned int hash_keyword_name 36 (const CGEN_KEYWORD *, const char *, int); 37 static unsigned int hash_keyword_value 38 (const CGEN_KEYWORD *, unsigned int); 39 static void build_keyword_hash_tables 40 (CGEN_KEYWORD *); 41 42 /* Return number of hash table entries to use for N elements. */ 43 #define KEYWORD_HASH_SIZE(n) ((n) <= 31 ? 17 : 31) 44 45 /* Look up *NAMEP in the keyword table KT. 46 The result is the keyword entry or NULL if not found. */ 47 48 const CGEN_KEYWORD_ENTRY * 49 cgen_keyword_lookup_name (CGEN_KEYWORD *kt, const char *name) 50 { 51 const CGEN_KEYWORD_ENTRY *ke; 52 const char *p,*n; 53 54 if (kt->name_hash_table == NULL) 55 build_keyword_hash_tables (kt); 56 57 ke = kt->name_hash_table[hash_keyword_name (kt, name, 0)]; 58 59 /* We do case insensitive comparisons. 60 If that ever becomes a problem, add an attribute that denotes 61 "do case sensitive comparisons". */ 62 63 while (ke != NULL) 64 { 65 n = name; 66 p = ke->name; 67 68 while (*p 69 && (*p == *n 70 || (ISALPHA (*p) && (TOLOWER (*p) == TOLOWER (*n))))) 71 ++n, ++p; 72 73 if (!*p && !*n) 74 return ke; 75 76 ke = ke->next_name; 77 } 78 79 if (kt->null_entry) 80 return kt->null_entry; 81 return NULL; 82 } 83 84 /* Look up VALUE in the keyword table KT. 85 The result is the keyword entry or NULL if not found. */ 86 87 const CGEN_KEYWORD_ENTRY * 88 cgen_keyword_lookup_value (CGEN_KEYWORD *kt, int value) 89 { 90 const CGEN_KEYWORD_ENTRY *ke; 91 92 if (kt->name_hash_table == NULL) 93 build_keyword_hash_tables (kt); 94 95 ke = kt->value_hash_table[hash_keyword_value (kt, value)]; 96 97 while (ke != NULL) 98 { 99 if (value == ke->value) 100 return ke; 101 ke = ke->next_value; 102 } 103 104 return NULL; 105 } 106 107 /* Add an entry to a keyword table. */ 108 109 void 110 cgen_keyword_add (CGEN_KEYWORD *kt, CGEN_KEYWORD_ENTRY *ke) 111 { 112 unsigned int hash; 113 size_t i; 114 115 if (kt->name_hash_table == NULL) 116 build_keyword_hash_tables (kt); 117 118 hash = hash_keyword_name (kt, ke->name, 0); 119 ke->next_name = kt->name_hash_table[hash]; 120 kt->name_hash_table[hash] = ke; 121 122 hash = hash_keyword_value (kt, ke->value); 123 ke->next_value = kt->value_hash_table[hash]; 124 kt->value_hash_table[hash] = ke; 125 126 if (ke->name[0] == 0) 127 kt->null_entry = ke; 128 129 for (i = 1; i < strlen (ke->name); i++) 130 if (! ISALNUM (ke->name[i]) 131 && ! strchr (kt->nonalpha_chars, ke->name[i])) 132 { 133 size_t idx = strlen (kt->nonalpha_chars); 134 135 /* If you hit this limit, please don't just 136 increase the size of the field, instead 137 look for a better algorithm. */ 138 if (idx >= sizeof (kt->nonalpha_chars) - 1) 139 abort (); 140 kt->nonalpha_chars[idx] = ke->name[i]; 141 kt->nonalpha_chars[idx+1] = 0; 142 } 143 } 144 145 /* FIXME: Need function to return count of keywords. */ 146 147 /* Initialize a keyword table search. 148 SPEC is a specification of what to search for. 149 A value of NULL means to find every keyword. 150 Currently NULL is the only acceptable value [further specification 151 deferred]. 152 The result is an opaque data item used to record the search status. 153 It is passed to each call to cgen_keyword_search_next. */ 154 155 CGEN_KEYWORD_SEARCH 156 cgen_keyword_search_init (CGEN_KEYWORD *kt, const char *spec) 157 { 158 CGEN_KEYWORD_SEARCH search; 159 160 /* FIXME: Need to specify format of PARAMS. */ 161 if (spec != NULL) 162 abort (); 163 164 if (kt->name_hash_table == NULL) 165 build_keyword_hash_tables (kt); 166 167 search.table = kt; 168 search.spec = spec; 169 search.current_hash = 0; 170 search.current_entry = NULL; 171 return search; 172 } 173 174 /* Return the next keyword specified by SEARCH. 175 The result is the next entry or NULL if there are no more. */ 176 177 const CGEN_KEYWORD_ENTRY * 178 cgen_keyword_search_next (CGEN_KEYWORD_SEARCH *search) 179 { 180 /* Has search finished? */ 181 if (search->current_hash == search->table->hash_table_size) 182 return NULL; 183 184 /* Search in progress? */ 185 if (search->current_entry != NULL 186 /* Anything left on this hash chain? */ 187 && search->current_entry->next_name != NULL) 188 { 189 search->current_entry = search->current_entry->next_name; 190 return search->current_entry; 191 } 192 193 /* Move to next hash chain [unless we haven't started yet]. */ 194 if (search->current_entry != NULL) 195 ++search->current_hash; 196 197 while (search->current_hash < search->table->hash_table_size) 198 { 199 search->current_entry = search->table->name_hash_table[search->current_hash]; 200 if (search->current_entry != NULL) 201 return search->current_entry; 202 ++search->current_hash; 203 } 204 205 return NULL; 206 } 207 208 /* Return first entry in hash chain for NAME. 209 If CASE_SENSITIVE_P is non-zero, return a case sensitive hash. */ 210 211 static unsigned int 212 hash_keyword_name (const CGEN_KEYWORD *kt, 213 const char *name, 214 int case_sensitive_p) 215 { 216 unsigned int hash; 217 218 if (case_sensitive_p) 219 for (hash = 0; *name; ++name) 220 hash = (hash * 97) + (unsigned char) *name; 221 else 222 for (hash = 0; *name; ++name) 223 hash = (hash * 97) + (unsigned char) TOLOWER (*name); 224 return hash % kt->hash_table_size; 225 } 226 227 /* Return first entry in hash chain for VALUE. */ 228 229 static unsigned int 230 hash_keyword_value (const CGEN_KEYWORD *kt, unsigned int value) 231 { 232 return value % kt->hash_table_size; 233 } 234 235 /* Build a keyword table's hash tables. 236 We probably needn't build the value hash table for the assembler when 237 we're using the disassembler, but we keep things simple. */ 238 239 static void 240 build_keyword_hash_tables (CGEN_KEYWORD *kt) 241 { 242 int i; 243 /* Use the number of compiled in entries as an estimate for the 244 typical sized table [not too many added at runtime]. */ 245 unsigned int size = KEYWORD_HASH_SIZE (kt->num_init_entries); 246 247 kt->hash_table_size = size; 248 kt->name_hash_table = (CGEN_KEYWORD_ENTRY **) 249 xmalloc (size * sizeof (CGEN_KEYWORD_ENTRY *)); 250 memset (kt->name_hash_table, 0, size * sizeof (CGEN_KEYWORD_ENTRY *)); 251 kt->value_hash_table = (CGEN_KEYWORD_ENTRY **) 252 xmalloc (size * sizeof (CGEN_KEYWORD_ENTRY *)); 253 memset (kt->value_hash_table, 0, size * sizeof (CGEN_KEYWORD_ENTRY *)); 254 255 /* The table is scanned backwards as we want keywords appearing earlier to 256 be prefered over later ones. */ 257 for (i = kt->num_init_entries - 1; i >= 0; --i) 258 cgen_keyword_add (kt, &kt->init_entries[i]); 259 } 260 261 /* Hardware support. */ 262 263 /* Lookup a hardware element by its name. 264 Returns NULL if NAME is not supported by the currently selected 265 mach/isa. */ 266 267 const CGEN_HW_ENTRY * 268 cgen_hw_lookup_by_name (CGEN_CPU_DESC cd, const char *name) 269 { 270 unsigned int i; 271 const CGEN_HW_ENTRY **hw = cd->hw_table.entries; 272 273 for (i = 0; i < cd->hw_table.num_entries; ++i) 274 if (hw[i] && strcmp (name, hw[i]->name) == 0) 275 return hw[i]; 276 277 return NULL; 278 } 279 280 /* Lookup a hardware element by its number. 281 Hardware elements are enumerated, however it may be possible to add some 282 at runtime, thus HWNUM is not an enum type but rather an int. 283 Returns NULL if HWNUM is not supported by the currently selected mach. */ 284 285 const CGEN_HW_ENTRY * 286 cgen_hw_lookup_by_num (CGEN_CPU_DESC cd, unsigned int hwnum) 287 { 288 unsigned int i; 289 const CGEN_HW_ENTRY **hw = cd->hw_table.entries; 290 291 /* ??? This can be speeded up. */ 292 for (i = 0; i < cd->hw_table.num_entries; ++i) 293 if (hw[i] && hwnum == hw[i]->type) 294 return hw[i]; 295 296 return NULL; 297 } 298 299 /* Operand support. */ 300 301 /* Lookup an operand by its name. 302 Returns NULL if NAME is not supported by the currently selected 303 mach/isa. */ 304 305 const CGEN_OPERAND * 306 cgen_operand_lookup_by_name (CGEN_CPU_DESC cd, const char *name) 307 { 308 unsigned int i; 309 const CGEN_OPERAND **op = cd->operand_table.entries; 310 311 for (i = 0; i < cd->operand_table.num_entries; ++i) 312 if (op[i] && strcmp (name, op[i]->name) == 0) 313 return op[i]; 314 315 return NULL; 316 } 317 318 /* Lookup an operand by its number. 319 Operands are enumerated, however it may be possible to add some 320 at runtime, thus OPNUM is not an enum type but rather an int. 321 Returns NULL if OPNUM is not supported by the currently selected 322 mach/isa. */ 323 324 const CGEN_OPERAND * 325 cgen_operand_lookup_by_num (CGEN_CPU_DESC cd, int opnum) 326 { 327 return cd->operand_table.entries[opnum]; 328 } 329 330 /* Instruction support. */ 331 332 /* Return number of instructions. This includes any added at runtime. */ 333 334 int 335 cgen_insn_count (CGEN_CPU_DESC cd) 336 { 337 int count = cd->insn_table.num_init_entries; 338 CGEN_INSN_LIST *rt_insns = cd->insn_table.new_entries; 339 340 for ( ; rt_insns != NULL; rt_insns = rt_insns->next) 341 ++count; 342 343 return count; 344 } 345 346 /* Return number of macro-instructions. 347 This includes any added at runtime. */ 348 349 int 350 cgen_macro_insn_count (CGEN_CPU_DESC cd) 351 { 352 int count = cd->macro_insn_table.num_init_entries; 353 CGEN_INSN_LIST *rt_insns = cd->macro_insn_table.new_entries; 354 355 for ( ; rt_insns != NULL; rt_insns = rt_insns->next) 356 ++count; 357 358 return count; 359 } 360 361 /* Cover function to read and properly byteswap an insn value. */ 362 363 CGEN_INSN_INT 364 cgen_get_insn_value (CGEN_CPU_DESC cd, unsigned char *buf, int length) 365 { 366 int big_p = (cd->insn_endian == CGEN_ENDIAN_BIG); 367 int insn_chunk_bitsize = cd->insn_chunk_bitsize; 368 CGEN_INSN_INT value = 0; 369 370 if (insn_chunk_bitsize != 0 && insn_chunk_bitsize < length) 371 { 372 /* We need to divide up the incoming value into insn_chunk_bitsize-length 373 segments, and endian-convert them, one at a time. */ 374 int i; 375 376 /* Enforce divisibility. */ 377 if ((length % insn_chunk_bitsize) != 0) 378 abort (); 379 380 for (i = 0; i < length; i += insn_chunk_bitsize) /* NB: i == bits */ 381 { 382 int index; 383 bfd_vma this_value; 384 index = i; /* NB: not dependent on endianness; opposite of cgen_put_insn_value! */ 385 this_value = bfd_get_bits (& buf[index / 8], insn_chunk_bitsize, big_p); 386 value = (value << insn_chunk_bitsize) | this_value; 387 } 388 } 389 else 390 { 391 value = bfd_get_bits (buf, length, cd->insn_endian == CGEN_ENDIAN_BIG); 392 } 393 394 return value; 395 } 396 397 /* Cover function to store an insn value properly byteswapped. */ 398 399 void 400 cgen_put_insn_value (CGEN_CPU_DESC cd, 401 unsigned char *buf, 402 int length, 403 CGEN_INSN_INT value) 404 { 405 int big_p = (cd->insn_endian == CGEN_ENDIAN_BIG); 406 int insn_chunk_bitsize = cd->insn_chunk_bitsize; 407 408 if (insn_chunk_bitsize != 0 && insn_chunk_bitsize < length) 409 { 410 /* We need to divide up the incoming value into insn_chunk_bitsize-length 411 segments, and endian-convert them, one at a time. */ 412 int i; 413 414 /* Enforce divisibility. */ 415 if ((length % insn_chunk_bitsize) != 0) 416 abort (); 417 418 for (i = 0; i < length; i += insn_chunk_bitsize) /* NB: i == bits */ 419 { 420 int index; 421 index = (length - insn_chunk_bitsize - i); /* NB: not dependent on endianness! */ 422 bfd_put_bits ((bfd_vma) value, & buf[index / 8], insn_chunk_bitsize, big_p); 423 value >>= insn_chunk_bitsize; 424 } 425 } 426 else 427 { 428 bfd_put_bits ((bfd_vma) value, buf, length, big_p); 429 } 430 } 431 432 /* Look up instruction INSN_*_VALUE and extract its fields. 433 INSN_INT_VALUE is used if CGEN_INT_INSN_P. 434 Otherwise INSN_BYTES_VALUE is used. 435 INSN, if non-null, is the insn table entry. 436 Otherwise INSN_*_VALUE is examined to compute it. 437 LENGTH is the bit length of INSN_*_VALUE if known, otherwise 0. 438 0 is only valid if `insn == NULL && ! CGEN_INT_INSN_P'. 439 If INSN != NULL, LENGTH must be valid. 440 ALIAS_P is non-zero if alias insns are to be included in the search. 441 442 The result is a pointer to the insn table entry, or NULL if the instruction 443 wasn't recognized. */ 444 445 /* ??? Will need to be revisited for VLIW architectures. */ 446 447 const CGEN_INSN * 448 cgen_lookup_insn (CGEN_CPU_DESC cd, 449 const CGEN_INSN *insn, 450 CGEN_INSN_INT insn_int_value, 451 /* ??? CGEN_INSN_BYTES would be a nice type name to use here. */ 452 unsigned char *insn_bytes_value, 453 int length, 454 CGEN_FIELDS *fields, 455 int alias_p) 456 { 457 unsigned char *buf; 458 CGEN_INSN_INT base_insn; 459 CGEN_EXTRACT_INFO ex_info; 460 CGEN_EXTRACT_INFO *info; 461 462 if (cd->int_insn_p) 463 { 464 info = NULL; 465 buf = (unsigned char *) alloca (cd->max_insn_bitsize / 8); 466 cgen_put_insn_value (cd, buf, length, insn_int_value); 467 base_insn = insn_int_value; 468 } 469 else 470 { 471 info = &ex_info; 472 ex_info.dis_info = NULL; 473 ex_info.insn_bytes = insn_bytes_value; 474 ex_info.valid = -1; 475 buf = insn_bytes_value; 476 base_insn = cgen_get_insn_value (cd, buf, length); 477 } 478 479 if (!insn) 480 { 481 const CGEN_INSN_LIST *insn_list; 482 483 /* The instructions are stored in hash lists. 484 Pick the first one and keep trying until we find the right one. */ 485 486 insn_list = cgen_dis_lookup_insn (cd, buf, base_insn); 487 while (insn_list != NULL) 488 { 489 insn = insn_list->insn; 490 491 if (alias_p 492 /* FIXME: Ensure ALIAS attribute always has same index. */ 493 || ! CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_ALIAS)) 494 { 495 /* Basic bit mask must be correct. */ 496 /* ??? May wish to allow target to defer this check until the 497 extract handler. */ 498 if ((base_insn & CGEN_INSN_BASE_MASK (insn)) 499 == CGEN_INSN_BASE_VALUE (insn)) 500 { 501 /* ??? 0 is passed for `pc' */ 502 int elength = CGEN_EXTRACT_FN (cd, insn) 503 (cd, insn, info, base_insn, fields, (bfd_vma) 0); 504 if (elength > 0) 505 { 506 /* sanity check */ 507 if (length != 0 && length != elength) 508 abort (); 509 return insn; 510 } 511 } 512 } 513 514 insn_list = insn_list->next; 515 } 516 } 517 else 518 { 519 /* Sanity check: can't pass an alias insn if ! alias_p. */ 520 if (! alias_p 521 && CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_ALIAS)) 522 abort (); 523 /* Sanity check: length must be correct. */ 524 if (length != CGEN_INSN_BITSIZE (insn)) 525 abort (); 526 527 /* ??? 0 is passed for `pc' */ 528 length = CGEN_EXTRACT_FN (cd, insn) 529 (cd, insn, info, base_insn, fields, (bfd_vma) 0); 530 /* Sanity check: must succeed. 531 Could relax this later if it ever proves useful. */ 532 if (length == 0) 533 abort (); 534 return insn; 535 } 536 537 return NULL; 538 } 539 540 /* Fill in the operand instances used by INSN whose operands are FIELDS. 541 INDICES is a pointer to a buffer of MAX_OPERAND_INSTANCES ints to be filled 542 in. */ 543 544 void 545 cgen_get_insn_operands (CGEN_CPU_DESC cd, 546 const CGEN_INSN *insn, 547 const CGEN_FIELDS *fields, 548 int *indices) 549 { 550 const CGEN_OPINST *opinst; 551 int i; 552 553 if (insn->opinst == NULL) 554 abort (); 555 for (i = 0, opinst = insn->opinst; opinst->type != CGEN_OPINST_END; ++i, ++opinst) 556 { 557 enum cgen_operand_type op_type = opinst->op_type; 558 if (op_type == CGEN_OPERAND_NIL) 559 indices[i] = opinst->index; 560 else 561 indices[i] = (*cd->get_int_operand) (cd, op_type, fields); 562 } 563 } 564 565 /* Cover function to cgen_get_insn_operands when either INSN or FIELDS 566 isn't known. 567 The INSN, INSN_*_VALUE, and LENGTH arguments are passed to 568 cgen_lookup_insn unchanged. 569 INSN_INT_VALUE is used if CGEN_INT_INSN_P. 570 Otherwise INSN_BYTES_VALUE is used. 571 572 The result is the insn table entry or NULL if the instruction wasn't 573 recognized. */ 574 575 const CGEN_INSN * 576 cgen_lookup_get_insn_operands (CGEN_CPU_DESC cd, 577 const CGEN_INSN *insn, 578 CGEN_INSN_INT insn_int_value, 579 /* ??? CGEN_INSN_BYTES would be a nice type name to use here. */ 580 unsigned char *insn_bytes_value, 581 int length, 582 int *indices, 583 CGEN_FIELDS *fields) 584 { 585 /* Pass non-zero for ALIAS_P only if INSN != NULL. 586 If INSN == NULL, we want a real insn. */ 587 insn = cgen_lookup_insn (cd, insn, insn_int_value, insn_bytes_value, 588 length, fields, insn != NULL); 589 if (! insn) 590 return NULL; 591 592 cgen_get_insn_operands (cd, insn, fields, indices); 593 return insn; 594 } 595 596 /* Allow signed overflow of instruction fields. */ 597 void 598 cgen_set_signed_overflow_ok (CGEN_CPU_DESC cd) 599 { 600 cd->signed_overflow_ok_p = 1; 601 } 602 603 /* Generate an error message if a signed field in an instruction overflows. */ 604 void 605 cgen_clear_signed_overflow_ok (CGEN_CPU_DESC cd) 606 { 607 cd->signed_overflow_ok_p = 0; 608 } 609 610 /* Will an error message be generated if a signed field in an instruction overflows ? */ 611 unsigned int 612 cgen_signed_overflow_ok_p (CGEN_CPU_DESC cd) 613 { 614 return cd->signed_overflow_ok_p; 615 } 616