| 1 | /* Configurable Xtensa ISA support. |
| 2 | Copyright 2003 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of BFD, the Binary File Descriptor library. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | |
| 20 | #include <stdio.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <sys/types.h> |
| 23 | #include <string.h> |
| 24 | |
| 25 | #include "xtensa-isa.h" |
| 26 | #include "xtensa-isa-internal.h" |
| 27 | |
| 28 | xtensa_isa xtensa_default_isa = NULL; |
| 29 | |
| 30 | static int |
| 31 | opname_lookup_compare (const void *v1, const void *v2) |
| 32 | { |
| 33 | opname_lookup_entry *e1 = (opname_lookup_entry *)v1; |
| 34 | opname_lookup_entry *e2 = (opname_lookup_entry *)v2; |
| 35 | |
| 36 | return strcmp (e1->key, e2->key); |
| 37 | } |
| 38 | |
| 39 | |
| 40 | xtensa_isa |
| 41 | xtensa_isa_init (void) |
| 42 | { |
| 43 | xtensa_isa isa; |
| 44 | int mod; |
| 45 | |
| 46 | isa = xtensa_load_isa (0); |
| 47 | if (isa == 0) |
| 48 | { |
| 49 | fprintf (stderr, "Failed to initialize Xtensa base ISA module\n"); |
| 50 | return NULL; |
| 51 | } |
| 52 | |
| 53 | for (mod = 1; xtensa_isa_modules[mod].get_num_opcodes_fn; mod++) |
| 54 | { |
| 55 | if (!xtensa_extend_isa (isa, mod)) |
| 56 | { |
| 57 | fprintf (stderr, "Failed to initialize Xtensa TIE ISA module\n"); |
| 58 | return NULL; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | return isa; |
| 63 | } |
| 64 | |
| 65 | /* ISA information. */ |
| 66 | |
| 67 | static int |
| 68 | xtensa_check_isa_config (xtensa_isa_internal *isa, |
| 69 | struct config_struct *config_table) |
| 70 | { |
| 71 | int i, j; |
| 72 | |
| 73 | if (!config_table) |
| 74 | { |
| 75 | fprintf (stderr, "Error: Empty configuration table in ISA DLL\n"); |
| 76 | return 0; |
| 77 | } |
| 78 | |
| 79 | /* For the first module, save a pointer to the table and record the |
| 80 | specified endianness and availability of the density option. */ |
| 81 | |
| 82 | if (isa->num_modules == 0) |
| 83 | { |
| 84 | int found_memory_order = 0; |
| 85 | |
| 86 | isa->config = config_table; |
| 87 | isa->has_density = 1; /* Default to have density option. */ |
| 88 | |
| 89 | for (i = 0; config_table[i].param_name; i++) |
| 90 | { |
| 91 | if (!strcmp (config_table[i].param_name, "IsaMemoryOrder")) |
| 92 | { |
| 93 | isa->is_big_endian = |
| 94 | (strcmp (config_table[i].param_value, "BigEndian") == 0); |
| 95 | found_memory_order = 1; |
| 96 | } |
| 97 | if (!strcmp (config_table[i].param_name, "IsaUseDensityInstruction")) |
| 98 | { |
| 99 | isa->has_density = atoi (config_table[i].param_value); |
| 100 | } |
| 101 | } |
| 102 | if (!found_memory_order) |
| 103 | { |
| 104 | fprintf (stderr, "Error: \"IsaMemoryOrder\" missing from " |
| 105 | "configuration table in ISA DLL\n"); |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | return 1; |
| 110 | } |
| 111 | |
| 112 | /* For subsequent modules, check that the parameters match. Note: This |
| 113 | code is sufficient to handle the current model where there are never |
| 114 | more than 2 modules; we might at some point want to handle cases where |
| 115 | module N > 0 specifies some parameters not included in the base table, |
| 116 | and we would then add those to isa->config so that subsequent modules |
| 117 | would check against them. */ |
| 118 | |
| 119 | for (i = 0; config_table[i].param_name; i++) |
| 120 | { |
| 121 | for (j = 0; isa->config[j].param_name; j++) |
| 122 | { |
| 123 | if (!strcmp (config_table[i].param_name, isa->config[j].param_name)) |
| 124 | { |
| 125 | int mismatch; |
| 126 | if (!strcmp (config_table[i].param_name, "IsaCoprocessorCount")) |
| 127 | { |
| 128 | /* Only require the coprocessor count to be <= the base. */ |
| 129 | int tiecnt = atoi (config_table[i].param_value); |
| 130 | int basecnt = atoi (isa->config[j].param_value); |
| 131 | mismatch = (tiecnt > basecnt); |
| 132 | } |
| 133 | else |
| 134 | mismatch = strcmp (config_table[i].param_value, |
| 135 | isa->config[j].param_value); |
| 136 | if (mismatch) |
| 137 | { |
| 138 | #define MISMATCH_MESSAGE \ |
| 139 | "Error: Configuration mismatch in the \"%s\" parameter:\n\ |
| 140 | the configuration used when the TIE file was compiled had a value of\n\ |
| 141 | \"%s\", while the current configuration has a value of\n\ |
| 142 | \"%s\". Please rerun the TIE compiler with a matching\n\ |
| 143 | configuration.\n" |
| 144 | fprintf (stderr, MISMATCH_MESSAGE, |
| 145 | config_table[i].param_name, |
| 146 | config_table[i].param_value, |
| 147 | isa->config[j].param_value); |
| 148 | return 0; |
| 149 | } |
| 150 | break; |
| 151 | } |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | return 1; |
| 156 | } |
| 157 | |
| 158 | |
| 159 | static int |
| 160 | xtensa_add_isa (xtensa_isa_internal *isa, libisa_module_specifier libisa) |
| 161 | { |
| 162 | int (*get_num_opcodes_fn) (void); |
| 163 | struct config_struct *(*get_config_table_fn) (void); |
| 164 | xtensa_opcode_internal **(*get_opcodes_fn) (void); |
| 165 | int (*decode_insn_fn) (const xtensa_insnbuf); |
| 166 | xtensa_opcode_internal **opcodes; |
| 167 | int opc, insn_size, prev_num_opcodes, new_num_opcodes, this_module; |
| 168 | |
| 169 | get_num_opcodes_fn = xtensa_isa_modules[libisa].get_num_opcodes_fn; |
| 170 | get_opcodes_fn = xtensa_isa_modules[libisa].get_opcodes_fn; |
| 171 | decode_insn_fn = xtensa_isa_modules[libisa].decode_insn_fn; |
| 172 | get_config_table_fn = xtensa_isa_modules[libisa].get_config_table_fn; |
| 173 | |
| 174 | if (!get_num_opcodes_fn || !get_opcodes_fn || !decode_insn_fn |
| 175 | || (!get_config_table_fn && isa->num_modules == 0)) |
| 176 | return 0; |
| 177 | |
| 178 | if (get_config_table_fn |
| 179 | && !xtensa_check_isa_config (isa, get_config_table_fn ())) |
| 180 | return 0; |
| 181 | |
| 182 | prev_num_opcodes = isa->num_opcodes; |
| 183 | new_num_opcodes = (*get_num_opcodes_fn) (); |
| 184 | |
| 185 | isa->num_opcodes += new_num_opcodes; |
| 186 | isa->opcode_table = (xtensa_opcode_internal **) |
| 187 | realloc (isa->opcode_table, isa->num_opcodes * |
| 188 | sizeof (xtensa_opcode_internal *)); |
| 189 | isa->opname_lookup_table = (opname_lookup_entry *) |
| 190 | realloc (isa->opname_lookup_table, isa->num_opcodes * |
| 191 | sizeof (opname_lookup_entry)); |
| 192 | |
| 193 | opcodes = (*get_opcodes_fn) (); |
| 194 | |
| 195 | insn_size = isa->insn_size; |
| 196 | for (opc = 0; opc < new_num_opcodes; opc++) |
| 197 | { |
| 198 | xtensa_opcode_internal *intopc = opcodes[opc]; |
| 199 | int newopc = prev_num_opcodes + opc; |
| 200 | isa->opcode_table[newopc] = intopc; |
| 201 | isa->opname_lookup_table[newopc].key = intopc->name; |
| 202 | isa->opname_lookup_table[newopc].opcode = newopc; |
| 203 | if (intopc->length > insn_size) |
| 204 | insn_size = intopc->length; |
| 205 | } |
| 206 | |
| 207 | isa->insn_size = insn_size; |
| 208 | isa->insnbuf_size = ((isa->insn_size + sizeof (xtensa_insnbuf_word) - 1) / |
| 209 | sizeof (xtensa_insnbuf_word)); |
| 210 | |
| 211 | qsort (isa->opname_lookup_table, isa->num_opcodes, |
| 212 | sizeof (opname_lookup_entry), opname_lookup_compare); |
| 213 | |
| 214 | /* Check for duplicate opcode names. */ |
| 215 | for (opc = 1; opc < isa->num_opcodes; opc++) |
| 216 | { |
| 217 | if (!opname_lookup_compare (&isa->opname_lookup_table[opc-1], |
| 218 | &isa->opname_lookup_table[opc])) |
| 219 | { |
| 220 | fprintf (stderr, "Error: Duplicate TIE opcode \"%s\"\n", |
| 221 | isa->opname_lookup_table[opc].key); |
| 222 | return 0; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | this_module = isa->num_modules; |
| 227 | isa->num_modules += 1; |
| 228 | |
| 229 | isa->module_opcode_base = (int *) realloc (isa->module_opcode_base, |
| 230 | isa->num_modules * sizeof (int)); |
| 231 | isa->module_decode_fn = (xtensa_insn_decode_fn *) |
| 232 | realloc (isa->module_decode_fn, isa->num_modules * |
| 233 | sizeof (xtensa_insn_decode_fn)); |
| 234 | |
| 235 | isa->module_opcode_base[this_module] = prev_num_opcodes; |
| 236 | isa->module_decode_fn[this_module] = decode_insn_fn; |
| 237 | |
| 238 | xtensa_default_isa = isa; |
| 239 | |
| 240 | return 1; /* Library was successfully added. */ |
| 241 | } |
| 242 | |
| 243 | |
| 244 | xtensa_isa |
| 245 | xtensa_load_isa (libisa_module_specifier libisa) |
| 246 | { |
| 247 | xtensa_isa_internal *isa; |
| 248 | |
| 249 | isa = (xtensa_isa_internal *) malloc (sizeof (xtensa_isa_internal)); |
| 250 | memset (isa, 0, sizeof (xtensa_isa_internal)); |
| 251 | if (!xtensa_add_isa (isa, libisa)) |
| 252 | { |
| 253 | xtensa_isa_free (isa); |
| 254 | return NULL; |
| 255 | } |
| 256 | return (xtensa_isa) isa; |
| 257 | } |
| 258 | |
| 259 | |
| 260 | int |
| 261 | xtensa_extend_isa (xtensa_isa isa, libisa_module_specifier libisa) |
| 262 | { |
| 263 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 264 | return xtensa_add_isa (intisa, libisa); |
| 265 | } |
| 266 | |
| 267 | |
| 268 | void |
| 269 | xtensa_isa_free (xtensa_isa isa) |
| 270 | { |
| 271 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 272 | if (intisa->opcode_table) |
| 273 | free (intisa->opcode_table); |
| 274 | if (intisa->opname_lookup_table) |
| 275 | free (intisa->opname_lookup_table); |
| 276 | if (intisa->module_opcode_base) |
| 277 | free (intisa->module_opcode_base); |
| 278 | if (intisa->module_decode_fn) |
| 279 | free (intisa->module_decode_fn); |
| 280 | free (intisa); |
| 281 | } |
| 282 | |
| 283 | |
| 284 | int |
| 285 | xtensa_insn_maxlength (xtensa_isa isa) |
| 286 | { |
| 287 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 288 | return intisa->insn_size; |
| 289 | } |
| 290 | |
| 291 | |
| 292 | int |
| 293 | xtensa_insnbuf_size (xtensa_isa isa) |
| 294 | { |
| 295 | xtensa_isa_internal *intisa = (xtensa_isa_internal *)isa; |
| 296 | return intisa->insnbuf_size; |
| 297 | } |
| 298 | |
| 299 | |
| 300 | int |
| 301 | xtensa_num_opcodes (xtensa_isa isa) |
| 302 | { |
| 303 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 304 | return intisa->num_opcodes; |
| 305 | } |
| 306 | |
| 307 | |
| 308 | xtensa_opcode |
| 309 | xtensa_opcode_lookup (xtensa_isa isa, const char *opname) |
| 310 | { |
| 311 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 312 | opname_lookup_entry entry, *result; |
| 313 | |
| 314 | entry.key = opname; |
| 315 | result = bsearch (&entry, intisa->opname_lookup_table, intisa->num_opcodes, |
| 316 | sizeof (opname_lookup_entry), opname_lookup_compare); |
| 317 | if (!result) return XTENSA_UNDEFINED; |
| 318 | return result->opcode; |
| 319 | } |
| 320 | |
| 321 | |
| 322 | xtensa_opcode |
| 323 | xtensa_decode_insn (xtensa_isa isa, const xtensa_insnbuf insn) |
| 324 | { |
| 325 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 326 | int n, opc; |
| 327 | for (n = 0; n < intisa->num_modules; n++) { |
| 328 | opc = (intisa->module_decode_fn[n]) (insn); |
| 329 | if (opc != XTENSA_UNDEFINED) |
| 330 | return intisa->module_opcode_base[n] + opc; |
| 331 | } |
| 332 | return XTENSA_UNDEFINED; |
| 333 | } |
| 334 | |
| 335 | |
| 336 | /* Opcode information. */ |
| 337 | |
| 338 | void |
| 339 | xtensa_encode_insn (xtensa_isa isa, xtensa_opcode opc, xtensa_insnbuf insn) |
| 340 | { |
| 341 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 342 | xtensa_insnbuf template = intisa->opcode_table[opc]->template(); |
| 343 | int len = intisa->opcode_table[opc]->length; |
| 344 | int n; |
| 345 | |
| 346 | /* Convert length to 32-bit words. */ |
| 347 | len = (len + 3) / 4; |
| 348 | |
| 349 | /* Copy the template. */ |
| 350 | for (n = 0; n < len; n++) |
| 351 | insn[n] = template[n]; |
| 352 | |
| 353 | /* Fill any unused buffer space with zeros. */ |
| 354 | for ( ; n < intisa->insnbuf_size; n++) |
| 355 | insn[n] = 0; |
| 356 | } |
| 357 | |
| 358 | |
| 359 | const char * |
| 360 | xtensa_opcode_name (xtensa_isa isa, xtensa_opcode opc) |
| 361 | { |
| 362 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 363 | return intisa->opcode_table[opc]->name; |
| 364 | } |
| 365 | |
| 366 | |
| 367 | int |
| 368 | xtensa_insn_length (xtensa_isa isa, xtensa_opcode opc) |
| 369 | { |
| 370 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 371 | return intisa->opcode_table[opc]->length; |
| 372 | } |
| 373 | |
| 374 | |
| 375 | int |
| 376 | xtensa_insn_length_from_first_byte (xtensa_isa isa, char first_byte) |
| 377 | { |
| 378 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 379 | int is_density = (first_byte & (intisa->is_big_endian ? 0x80 : 0x08)) != 0; |
| 380 | return (intisa->has_density && is_density ? 2 : 3); |
| 381 | } |
| 382 | |
| 383 | |
| 384 | int |
| 385 | xtensa_num_operands (xtensa_isa isa, xtensa_opcode opc) |
| 386 | { |
| 387 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 388 | return intisa->opcode_table[opc]->iclass->num_operands; |
| 389 | } |
| 390 | |
| 391 | |
| 392 | xtensa_operand |
| 393 | xtensa_get_operand (xtensa_isa isa, xtensa_opcode opc, int opnd) |
| 394 | { |
| 395 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 396 | xtensa_iclass_internal *iclass = intisa->opcode_table[opc]->iclass; |
| 397 | if (opnd >= iclass->num_operands) |
| 398 | return NULL; |
| 399 | return (xtensa_operand) iclass->operands[opnd]; |
| 400 | } |
| 401 | |
| 402 | |
| 403 | /* Operand information. */ |
| 404 | |
| 405 | char * |
| 406 | xtensa_operand_kind (xtensa_operand opnd) |
| 407 | { |
| 408 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 409 | return intop->operand_kind; |
| 410 | } |
| 411 | |
| 412 | |
| 413 | char |
| 414 | xtensa_operand_inout (xtensa_operand opnd) |
| 415 | { |
| 416 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 417 | return intop->inout; |
| 418 | } |
| 419 | |
| 420 | |
| 421 | uint32 |
| 422 | xtensa_operand_get_field (xtensa_operand opnd, const xtensa_insnbuf insn) |
| 423 | { |
| 424 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 425 | return (*intop->get_field) (insn); |
| 426 | } |
| 427 | |
| 428 | |
| 429 | void |
| 430 | xtensa_operand_set_field (xtensa_operand opnd, xtensa_insnbuf insn, uint32 val) |
| 431 | { |
| 432 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 433 | return (*intop->set_field) (insn, val); |
| 434 | } |
| 435 | |
| 436 | |
| 437 | xtensa_encode_result |
| 438 | xtensa_operand_encode (xtensa_operand opnd, uint32 *valp) |
| 439 | { |
| 440 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 441 | return (*intop->encode) (valp); |
| 442 | } |
| 443 | |
| 444 | |
| 445 | uint32 |
| 446 | xtensa_operand_decode (xtensa_operand opnd, uint32 val) |
| 447 | { |
| 448 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 449 | return (*intop->decode) (val); |
| 450 | } |
| 451 | |
| 452 | |
| 453 | int |
| 454 | xtensa_operand_isPCRelative (xtensa_operand opnd) |
| 455 | { |
| 456 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 457 | return intop->isPCRelative; |
| 458 | } |
| 459 | |
| 460 | |
| 461 | uint32 |
| 462 | xtensa_operand_do_reloc (xtensa_operand opnd, uint32 addr, uint32 pc) |
| 463 | { |
| 464 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 465 | if (!intop->isPCRelative) |
| 466 | return addr; |
| 467 | return (*intop->do_reloc) (addr, pc); |
| 468 | } |
| 469 | |
| 470 | |
| 471 | uint32 |
| 472 | xtensa_operand_undo_reloc (xtensa_operand opnd, uint32 offset, uint32 pc) |
| 473 | { |
| 474 | xtensa_operand_internal *intop = (xtensa_operand_internal *) opnd; |
| 475 | if (!intop->isPCRelative) |
| 476 | return offset; |
| 477 | return (*intop->undo_reloc) (offset, pc); |
| 478 | } |
| 479 | |
| 480 | |
| 481 | /* Instruction buffers. */ |
| 482 | |
| 483 | xtensa_insnbuf |
| 484 | xtensa_insnbuf_alloc (xtensa_isa isa) |
| 485 | { |
| 486 | return (xtensa_insnbuf) malloc (xtensa_insnbuf_size (isa) * |
| 487 | sizeof (xtensa_insnbuf_word)); |
| 488 | } |
| 489 | |
| 490 | |
| 491 | void |
| 492 | xtensa_insnbuf_free (xtensa_insnbuf buf) |
| 493 | { |
| 494 | free( buf ); |
| 495 | } |
| 496 | |
| 497 | |
| 498 | /* Given <byte_index>, the index of a byte in a xtensa_insnbuf, our |
| 499 | internal representation of a xtensa instruction word, return the index of |
| 500 | its word and the bit index of its low order byte in the xtensa_insnbuf. */ |
| 501 | |
| 502 | static inline int |
| 503 | byte_to_word_index (int byte_index) |
| 504 | { |
| 505 | return byte_index / sizeof (xtensa_insnbuf_word); |
| 506 | } |
| 507 | |
| 508 | |
| 509 | static inline int |
| 510 | byte_to_bit_index (int byte_index) |
| 511 | { |
| 512 | return (byte_index & 0x3) * 8; |
| 513 | } |
| 514 | |
| 515 | |
| 516 | /* Copy an instruction in the 32 bit words pointed at by <insn> to characters |
| 517 | pointed at by <cp>. This is more complicated than you might think because |
| 518 | we want 16 bit instructions in bytes 2,3 for big endian. This function |
| 519 | allows us to specify which byte in <insn> to start with and which way to |
| 520 | increment, allowing trivial implementation for both big and little endian. |
| 521 | And it seems to make pretty good code for both. */ |
| 522 | |
| 523 | void |
| 524 | xtensa_insnbuf_to_chars (xtensa_isa isa, const xtensa_insnbuf insn, char *cp) |
| 525 | { |
| 526 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 527 | int insn_size = xtensa_insn_maxlength (intisa); |
| 528 | int fence_post, start, increment, i, byte_count; |
| 529 | xtensa_opcode opc; |
| 530 | |
| 531 | if (intisa->is_big_endian) |
| 532 | { |
| 533 | start = insn_size - 1; |
| 534 | increment = -1; |
| 535 | } |
| 536 | else |
| 537 | { |
| 538 | start = 0; |
| 539 | increment = 1; |
| 540 | } |
| 541 | |
| 542 | /* Find the opcode; do nothing if the buffer does not contain a valid |
| 543 | instruction since we need to know how many bytes to copy. */ |
| 544 | opc = xtensa_decode_insn (isa, insn); |
| 545 | if (opc == XTENSA_UNDEFINED) |
| 546 | return; |
| 547 | |
| 548 | byte_count = xtensa_insn_length (isa, opc); |
| 549 | fence_post = start + (byte_count * increment); |
| 550 | |
| 551 | for (i = start; i != fence_post; i += increment, ++cp) |
| 552 | { |
| 553 | int word_inx = byte_to_word_index (i); |
| 554 | int bit_inx = byte_to_bit_index (i); |
| 555 | |
| 556 | *cp = (insn[word_inx] >> bit_inx) & 0xff; |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | /* Inward conversion from byte stream to xtensa_insnbuf. See |
| 561 | xtensa_insnbuf_to_chars for a discussion of why this is |
| 562 | complicated by endianness. */ |
| 563 | |
| 564 | void |
| 565 | xtensa_insnbuf_from_chars (xtensa_isa isa, xtensa_insnbuf insn, const char* cp) |
| 566 | { |
| 567 | xtensa_isa_internal *intisa = (xtensa_isa_internal *) isa; |
| 568 | int insn_size = xtensa_insn_maxlength (intisa); |
| 569 | int fence_post, start, increment, i; |
| 570 | |
| 571 | if (intisa->is_big_endian) |
| 572 | { |
| 573 | start = insn_size - 1; |
| 574 | increment = -1; |
| 575 | } |
| 576 | else |
| 577 | { |
| 578 | start = 0; |
| 579 | increment = 1; |
| 580 | } |
| 581 | |
| 582 | fence_post = start + (insn_size * increment); |
| 583 | memset (insn, 0, xtensa_insnbuf_size (isa) * sizeof (xtensa_insnbuf_word)); |
| 584 | |
| 585 | for ( i = start; i != fence_post; i += increment, ++cp ) |
| 586 | { |
| 587 | int word_inx = byte_to_word_index (i); |
| 588 | int bit_inx = byte_to_bit_index (i); |
| 589 | |
| 590 | insn[word_inx] |= (*cp & 0xff) << bit_inx; |
| 591 | } |
| 592 | } |
| 593 | |