| 1 | /* DWARF 2 location expression support for GDB. |
| 2 | |
| 3 | Copyright (C) 2003, 2005, 2007, 2008, 2009, 2010, 2011 |
| 4 | Free Software Foundation, Inc. |
| 5 | |
| 6 | Contributed by Daniel Jacobowitz, MontaVista Software, Inc. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "ui-out.h" |
| 25 | #include "value.h" |
| 26 | #include "frame.h" |
| 27 | #include "gdbcore.h" |
| 28 | #include "target.h" |
| 29 | #include "inferior.h" |
| 30 | #include "ax.h" |
| 31 | #include "ax-gdb.h" |
| 32 | #include "regcache.h" |
| 33 | #include "objfiles.h" |
| 34 | #include "exceptions.h" |
| 35 | #include "block.h" |
| 36 | |
| 37 | #include "dwarf2.h" |
| 38 | #include "dwarf2expr.h" |
| 39 | #include "dwarf2loc.h" |
| 40 | #include "dwarf2-frame.h" |
| 41 | |
| 42 | #include "gdb_string.h" |
| 43 | #include "gdb_assert.h" |
| 44 | |
| 45 | extern int dwarf2_always_disassemble; |
| 46 | |
| 47 | static void |
| 48 | dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, |
| 49 | const gdb_byte **start, size_t *length); |
| 50 | |
| 51 | static struct value * |
| 52 | dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame, |
| 53 | const gdb_byte *data, unsigned short size, |
| 54 | struct dwarf2_per_cu_data *per_cu, |
| 55 | LONGEST byte_offset); |
| 56 | |
| 57 | /* A function for dealing with location lists. Given a |
| 58 | symbol baton (BATON) and a pc value (PC), find the appropriate |
| 59 | location expression, set *LOCEXPR_LENGTH, and return a pointer |
| 60 | to the beginning of the expression. Returns NULL on failure. |
| 61 | |
| 62 | For now, only return the first matching location expression; there |
| 63 | can be more than one in the list. */ |
| 64 | |
| 65 | const gdb_byte * |
| 66 | dwarf2_find_location_expression (struct dwarf2_loclist_baton *baton, |
| 67 | size_t *locexpr_length, CORE_ADDR pc) |
| 68 | { |
| 69 | CORE_ADDR low, high; |
| 70 | const gdb_byte *loc_ptr, *buf_end; |
| 71 | int length; |
| 72 | struct objfile *objfile = dwarf2_per_cu_objfile (baton->per_cu); |
| 73 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
| 74 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 75 | unsigned int addr_size = dwarf2_per_cu_addr_size (baton->per_cu); |
| 76 | int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd); |
| 77 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); |
| 78 | /* Adjust base_address for relocatable objects. */ |
| 79 | CORE_ADDR base_offset = dwarf2_per_cu_text_offset (baton->per_cu); |
| 80 | CORE_ADDR base_address = baton->base_address + base_offset; |
| 81 | |
| 82 | loc_ptr = baton->data; |
| 83 | buf_end = baton->data + baton->size; |
| 84 | |
| 85 | while (1) |
| 86 | { |
| 87 | if (buf_end - loc_ptr < 2 * addr_size) |
| 88 | error (_("dwarf2_find_location_expression: " |
| 89 | "Corrupted DWARF expression.")); |
| 90 | |
| 91 | if (signed_addr_p) |
| 92 | low = extract_signed_integer (loc_ptr, addr_size, byte_order); |
| 93 | else |
| 94 | low = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
| 95 | loc_ptr += addr_size; |
| 96 | |
| 97 | if (signed_addr_p) |
| 98 | high = extract_signed_integer (loc_ptr, addr_size, byte_order); |
| 99 | else |
| 100 | high = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
| 101 | loc_ptr += addr_size; |
| 102 | |
| 103 | /* A base-address-selection entry. */ |
| 104 | if ((low & base_mask) == base_mask) |
| 105 | { |
| 106 | base_address = high + base_offset; |
| 107 | continue; |
| 108 | } |
| 109 | |
| 110 | /* An end-of-list entry. */ |
| 111 | if (low == 0 && high == 0) |
| 112 | return NULL; |
| 113 | |
| 114 | /* Otherwise, a location expression entry. */ |
| 115 | low += base_address; |
| 116 | high += base_address; |
| 117 | |
| 118 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); |
| 119 | loc_ptr += 2; |
| 120 | |
| 121 | if (pc >= low && pc < high) |
| 122 | { |
| 123 | *locexpr_length = length; |
| 124 | return loc_ptr; |
| 125 | } |
| 126 | |
| 127 | loc_ptr += length; |
| 128 | } |
| 129 | } |
| 130 | |
| 131 | /* This is the baton used when performing dwarf2 expression |
| 132 | evaluation. */ |
| 133 | struct dwarf_expr_baton |
| 134 | { |
| 135 | struct frame_info *frame; |
| 136 | struct dwarf2_per_cu_data *per_cu; |
| 137 | }; |
| 138 | |
| 139 | /* Helper functions for dwarf2_evaluate_loc_desc. */ |
| 140 | |
| 141 | /* Using the frame specified in BATON, return the value of register |
| 142 | REGNUM, treated as a pointer. */ |
| 143 | static CORE_ADDR |
| 144 | dwarf_expr_read_reg (void *baton, int dwarf_regnum) |
| 145 | { |
| 146 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
| 147 | struct gdbarch *gdbarch = get_frame_arch (debaton->frame); |
| 148 | CORE_ADDR result; |
| 149 | int regnum; |
| 150 | |
| 151 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum); |
| 152 | result = address_from_register (builtin_type (gdbarch)->builtin_data_ptr, |
| 153 | regnum, debaton->frame); |
| 154 | return result; |
| 155 | } |
| 156 | |
| 157 | /* Read memory at ADDR (length LEN) into BUF. */ |
| 158 | |
| 159 | static void |
| 160 | dwarf_expr_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
| 161 | { |
| 162 | read_memory (addr, buf, len); |
| 163 | } |
| 164 | |
| 165 | /* Using the frame specified in BATON, find the location expression |
| 166 | describing the frame base. Return a pointer to it in START and |
| 167 | its length in LENGTH. */ |
| 168 | static void |
| 169 | dwarf_expr_frame_base (void *baton, const gdb_byte **start, size_t * length) |
| 170 | { |
| 171 | /* FIXME: cagney/2003-03-26: This code should be using |
| 172 | get_frame_base_address(), and then implement a dwarf2 specific |
| 173 | this_base method. */ |
| 174 | struct symbol *framefunc; |
| 175 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
| 176 | |
| 177 | /* Use block_linkage_function, which returns a real (not inlined) |
| 178 | function, instead of get_frame_function, which may return an |
| 179 | inlined function. */ |
| 180 | framefunc = block_linkage_function (get_frame_block (debaton->frame, NULL)); |
| 181 | |
| 182 | /* If we found a frame-relative symbol then it was certainly within |
| 183 | some function associated with a frame. If we can't find the frame, |
| 184 | something has gone wrong. */ |
| 185 | gdb_assert (framefunc != NULL); |
| 186 | |
| 187 | dwarf_expr_frame_base_1 (framefunc, |
| 188 | get_frame_address_in_block (debaton->frame), |
| 189 | start, length); |
| 190 | } |
| 191 | |
| 192 | static void |
| 193 | dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, |
| 194 | const gdb_byte **start, size_t *length) |
| 195 | { |
| 196 | if (SYMBOL_LOCATION_BATON (framefunc) == NULL) |
| 197 | *start = NULL; |
| 198 | else if (SYMBOL_COMPUTED_OPS (framefunc) == &dwarf2_loclist_funcs) |
| 199 | { |
| 200 | struct dwarf2_loclist_baton *symbaton; |
| 201 | |
| 202 | symbaton = SYMBOL_LOCATION_BATON (framefunc); |
| 203 | *start = dwarf2_find_location_expression (symbaton, length, pc); |
| 204 | } |
| 205 | else |
| 206 | { |
| 207 | struct dwarf2_locexpr_baton *symbaton; |
| 208 | |
| 209 | symbaton = SYMBOL_LOCATION_BATON (framefunc); |
| 210 | if (symbaton != NULL) |
| 211 | { |
| 212 | *length = symbaton->size; |
| 213 | *start = symbaton->data; |
| 214 | } |
| 215 | else |
| 216 | *start = NULL; |
| 217 | } |
| 218 | |
| 219 | if (*start == NULL) |
| 220 | error (_("Could not find the frame base for \"%s\"."), |
| 221 | SYMBOL_NATURAL_NAME (framefunc)); |
| 222 | } |
| 223 | |
| 224 | /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for |
| 225 | the frame in BATON. */ |
| 226 | |
| 227 | static CORE_ADDR |
| 228 | dwarf_expr_frame_cfa (void *baton) |
| 229 | { |
| 230 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
| 231 | |
| 232 | return dwarf2_frame_cfa (debaton->frame); |
| 233 | } |
| 234 | |
| 235 | /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for |
| 236 | the frame in BATON. */ |
| 237 | |
| 238 | static CORE_ADDR |
| 239 | dwarf_expr_frame_pc (void *baton) |
| 240 | { |
| 241 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
| 242 | |
| 243 | return get_frame_address_in_block (debaton->frame); |
| 244 | } |
| 245 | |
| 246 | /* Using the objfile specified in BATON, find the address for the |
| 247 | current thread's thread-local storage with offset OFFSET. */ |
| 248 | static CORE_ADDR |
| 249 | dwarf_expr_tls_address (void *baton, CORE_ADDR offset) |
| 250 | { |
| 251 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
| 252 | struct objfile *objfile = dwarf2_per_cu_objfile (debaton->per_cu); |
| 253 | |
| 254 | return target_translate_tls_address (objfile, offset); |
| 255 | } |
| 256 | |
| 257 | /* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in |
| 258 | current CU (as is PER_CU). State of the CTX is not affected by the |
| 259 | call and return. */ |
| 260 | |
| 261 | static void |
| 262 | per_cu_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset, |
| 263 | struct dwarf2_per_cu_data *per_cu, |
| 264 | CORE_ADDR (*get_frame_pc) (void *baton), |
| 265 | void *baton) |
| 266 | { |
| 267 | struct dwarf2_locexpr_baton block; |
| 268 | |
| 269 | block = dwarf2_fetch_die_location_block (die_offset, per_cu, |
| 270 | get_frame_pc, baton); |
| 271 | |
| 272 | /* DW_OP_call_ref is currently not supported. */ |
| 273 | gdb_assert (block.per_cu == per_cu); |
| 274 | |
| 275 | dwarf_expr_eval (ctx, block.data, block.size); |
| 276 | } |
| 277 | |
| 278 | /* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc. */ |
| 279 | |
| 280 | static void |
| 281 | dwarf_expr_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset) |
| 282 | { |
| 283 | struct dwarf_expr_baton *debaton = ctx->baton; |
| 284 | |
| 285 | return per_cu_dwarf_call (ctx, die_offset, debaton->per_cu, |
| 286 | ctx->get_frame_pc, ctx->baton); |
| 287 | } |
| 288 | |
| 289 | struct piece_closure |
| 290 | { |
| 291 | /* Reference count. */ |
| 292 | int refc; |
| 293 | |
| 294 | /* The CU from which this closure's expression came. */ |
| 295 | struct dwarf2_per_cu_data *per_cu; |
| 296 | |
| 297 | /* The number of pieces used to describe this variable. */ |
| 298 | int n_pieces; |
| 299 | |
| 300 | /* The target address size, used only for DWARF_VALUE_STACK. */ |
| 301 | int addr_size; |
| 302 | |
| 303 | /* The pieces themselves. */ |
| 304 | struct dwarf_expr_piece *pieces; |
| 305 | }; |
| 306 | |
| 307 | /* Allocate a closure for a value formed from separately-described |
| 308 | PIECES. */ |
| 309 | |
| 310 | static struct piece_closure * |
| 311 | allocate_piece_closure (struct dwarf2_per_cu_data *per_cu, |
| 312 | int n_pieces, struct dwarf_expr_piece *pieces, |
| 313 | int addr_size) |
| 314 | { |
| 315 | struct piece_closure *c = XZALLOC (struct piece_closure); |
| 316 | |
| 317 | c->refc = 1; |
| 318 | c->per_cu = per_cu; |
| 319 | c->n_pieces = n_pieces; |
| 320 | c->addr_size = addr_size; |
| 321 | c->pieces = XCALLOC (n_pieces, struct dwarf_expr_piece); |
| 322 | |
| 323 | memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece)); |
| 324 | |
| 325 | return c; |
| 326 | } |
| 327 | |
| 328 | /* The lowest-level function to extract bits from a byte buffer. |
| 329 | SOURCE is the buffer. It is updated if we read to the end of a |
| 330 | byte. |
| 331 | SOURCE_OFFSET_BITS is the offset of the first bit to read. It is |
| 332 | updated to reflect the number of bits actually read. |
| 333 | NBITS is the number of bits we want to read. It is updated to |
| 334 | reflect the number of bits actually read. This function may read |
| 335 | fewer bits. |
| 336 | BITS_BIG_ENDIAN is taken directly from gdbarch. |
| 337 | This function returns the extracted bits. */ |
| 338 | |
| 339 | static unsigned int |
| 340 | extract_bits_primitive (const gdb_byte **source, |
| 341 | unsigned int *source_offset_bits, |
| 342 | int *nbits, int bits_big_endian) |
| 343 | { |
| 344 | unsigned int avail, mask, datum; |
| 345 | |
| 346 | gdb_assert (*source_offset_bits < 8); |
| 347 | |
| 348 | avail = 8 - *source_offset_bits; |
| 349 | if (avail > *nbits) |
| 350 | avail = *nbits; |
| 351 | |
| 352 | mask = (1 << avail) - 1; |
| 353 | datum = **source; |
| 354 | if (bits_big_endian) |
| 355 | datum >>= 8 - (*source_offset_bits + *nbits); |
| 356 | else |
| 357 | datum >>= *source_offset_bits; |
| 358 | datum &= mask; |
| 359 | |
| 360 | *nbits -= avail; |
| 361 | *source_offset_bits += avail; |
| 362 | if (*source_offset_bits >= 8) |
| 363 | { |
| 364 | *source_offset_bits -= 8; |
| 365 | ++*source; |
| 366 | } |
| 367 | |
| 368 | return datum; |
| 369 | } |
| 370 | |
| 371 | /* Extract some bits from a source buffer and move forward in the |
| 372 | buffer. |
| 373 | |
| 374 | SOURCE is the source buffer. It is updated as bytes are read. |
| 375 | SOURCE_OFFSET_BITS is the offset into SOURCE. It is updated as |
| 376 | bits are read. |
| 377 | NBITS is the number of bits to read. |
| 378 | BITS_BIG_ENDIAN is taken directly from gdbarch. |
| 379 | |
| 380 | This function returns the bits that were read. */ |
| 381 | |
| 382 | static unsigned int |
| 383 | extract_bits (const gdb_byte **source, unsigned int *source_offset_bits, |
| 384 | int nbits, int bits_big_endian) |
| 385 | { |
| 386 | unsigned int datum; |
| 387 | |
| 388 | gdb_assert (nbits > 0 && nbits <= 8); |
| 389 | |
| 390 | datum = extract_bits_primitive (source, source_offset_bits, &nbits, |
| 391 | bits_big_endian); |
| 392 | if (nbits > 0) |
| 393 | { |
| 394 | unsigned int more; |
| 395 | |
| 396 | more = extract_bits_primitive (source, source_offset_bits, &nbits, |
| 397 | bits_big_endian); |
| 398 | if (bits_big_endian) |
| 399 | datum <<= nbits; |
| 400 | else |
| 401 | more <<= nbits; |
| 402 | datum |= more; |
| 403 | } |
| 404 | |
| 405 | return datum; |
| 406 | } |
| 407 | |
| 408 | /* Write some bits into a buffer and move forward in the buffer. |
| 409 | |
| 410 | DATUM is the bits to write. The low-order bits of DATUM are used. |
| 411 | DEST is the destination buffer. It is updated as bytes are |
| 412 | written. |
| 413 | DEST_OFFSET_BITS is the bit offset in DEST at which writing is |
| 414 | done. |
| 415 | NBITS is the number of valid bits in DATUM. |
| 416 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ |
| 417 | |
| 418 | static void |
| 419 | insert_bits (unsigned int datum, |
| 420 | gdb_byte *dest, unsigned int dest_offset_bits, |
| 421 | int nbits, int bits_big_endian) |
| 422 | { |
| 423 | unsigned int mask; |
| 424 | |
| 425 | gdb_assert (dest_offset_bits + nbits <= 8); |
| 426 | |
| 427 | mask = (1 << nbits) - 1; |
| 428 | if (bits_big_endian) |
| 429 | { |
| 430 | datum <<= 8 - (dest_offset_bits + nbits); |
| 431 | mask <<= 8 - (dest_offset_bits + nbits); |
| 432 | } |
| 433 | else |
| 434 | { |
| 435 | datum <<= dest_offset_bits; |
| 436 | mask <<= dest_offset_bits; |
| 437 | } |
| 438 | |
| 439 | gdb_assert ((datum & ~mask) == 0); |
| 440 | |
| 441 | *dest = (*dest & ~mask) | datum; |
| 442 | } |
| 443 | |
| 444 | /* Copy bits from a source to a destination. |
| 445 | |
| 446 | DEST is where the bits should be written. |
| 447 | DEST_OFFSET_BITS is the bit offset into DEST. |
| 448 | SOURCE is the source of bits. |
| 449 | SOURCE_OFFSET_BITS is the bit offset into SOURCE. |
| 450 | BIT_COUNT is the number of bits to copy. |
| 451 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ |
| 452 | |
| 453 | static void |
| 454 | copy_bitwise (gdb_byte *dest, unsigned int dest_offset_bits, |
| 455 | const gdb_byte *source, unsigned int source_offset_bits, |
| 456 | unsigned int bit_count, |
| 457 | int bits_big_endian) |
| 458 | { |
| 459 | unsigned int dest_avail; |
| 460 | int datum; |
| 461 | |
| 462 | /* Reduce everything to byte-size pieces. */ |
| 463 | dest += dest_offset_bits / 8; |
| 464 | dest_offset_bits %= 8; |
| 465 | source += source_offset_bits / 8; |
| 466 | source_offset_bits %= 8; |
| 467 | |
| 468 | dest_avail = 8 - dest_offset_bits % 8; |
| 469 | |
| 470 | /* See if we can fill the first destination byte. */ |
| 471 | if (dest_avail < bit_count) |
| 472 | { |
| 473 | datum = extract_bits (&source, &source_offset_bits, dest_avail, |
| 474 | bits_big_endian); |
| 475 | insert_bits (datum, dest, dest_offset_bits, dest_avail, bits_big_endian); |
| 476 | ++dest; |
| 477 | dest_offset_bits = 0; |
| 478 | bit_count -= dest_avail; |
| 479 | } |
| 480 | |
| 481 | /* Now, either DEST_OFFSET_BITS is byte-aligned, or we have fewer |
| 482 | than 8 bits remaining. */ |
| 483 | gdb_assert (dest_offset_bits % 8 == 0 || bit_count < 8); |
| 484 | for (; bit_count >= 8; bit_count -= 8) |
| 485 | { |
| 486 | datum = extract_bits (&source, &source_offset_bits, 8, bits_big_endian); |
| 487 | *dest++ = (gdb_byte) datum; |
| 488 | } |
| 489 | |
| 490 | /* Finally, we may have a few leftover bits. */ |
| 491 | gdb_assert (bit_count <= 8 - dest_offset_bits % 8); |
| 492 | if (bit_count > 0) |
| 493 | { |
| 494 | datum = extract_bits (&source, &source_offset_bits, bit_count, |
| 495 | bits_big_endian); |
| 496 | insert_bits (datum, dest, dest_offset_bits, bit_count, bits_big_endian); |
| 497 | } |
| 498 | } |
| 499 | |
| 500 | static void |
| 501 | read_pieced_value (struct value *v) |
| 502 | { |
| 503 | int i; |
| 504 | long offset = 0; |
| 505 | ULONGEST bits_to_skip; |
| 506 | gdb_byte *contents; |
| 507 | struct piece_closure *c |
| 508 | = (struct piece_closure *) value_computed_closure (v); |
| 509 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (v)); |
| 510 | size_t type_len; |
| 511 | size_t buffer_size = 0; |
| 512 | char *buffer = NULL; |
| 513 | struct cleanup *cleanup; |
| 514 | int bits_big_endian |
| 515 | = gdbarch_bits_big_endian (get_type_arch (value_type (v))); |
| 516 | |
| 517 | if (value_type (v) != value_enclosing_type (v)) |
| 518 | internal_error (__FILE__, __LINE__, |
| 519 | _("Should not be able to create a lazy value with " |
| 520 | "an enclosing type")); |
| 521 | |
| 522 | cleanup = make_cleanup (free_current_contents, &buffer); |
| 523 | |
| 524 | contents = value_contents_raw (v); |
| 525 | bits_to_skip = 8 * value_offset (v); |
| 526 | if (value_bitsize (v)) |
| 527 | { |
| 528 | bits_to_skip += value_bitpos (v); |
| 529 | type_len = value_bitsize (v); |
| 530 | } |
| 531 | else |
| 532 | type_len = 8 * TYPE_LENGTH (value_type (v)); |
| 533 | |
| 534 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
| 535 | { |
| 536 | struct dwarf_expr_piece *p = &c->pieces[i]; |
| 537 | size_t this_size, this_size_bits; |
| 538 | long dest_offset_bits, source_offset_bits, source_offset; |
| 539 | const gdb_byte *intermediate_buffer; |
| 540 | |
| 541 | /* Compute size, source, and destination offsets for copying, in |
| 542 | bits. */ |
| 543 | this_size_bits = p->size; |
| 544 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) |
| 545 | { |
| 546 | bits_to_skip -= this_size_bits; |
| 547 | continue; |
| 548 | } |
| 549 | if (this_size_bits > type_len - offset) |
| 550 | this_size_bits = type_len - offset; |
| 551 | if (bits_to_skip > 0) |
| 552 | { |
| 553 | dest_offset_bits = 0; |
| 554 | source_offset_bits = bits_to_skip; |
| 555 | this_size_bits -= bits_to_skip; |
| 556 | bits_to_skip = 0; |
| 557 | } |
| 558 | else |
| 559 | { |
| 560 | dest_offset_bits = offset; |
| 561 | source_offset_bits = 0; |
| 562 | } |
| 563 | |
| 564 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; |
| 565 | source_offset = source_offset_bits / 8; |
| 566 | if (buffer_size < this_size) |
| 567 | { |
| 568 | buffer_size = this_size; |
| 569 | buffer = xrealloc (buffer, buffer_size); |
| 570 | } |
| 571 | intermediate_buffer = buffer; |
| 572 | |
| 573 | /* Copy from the source to DEST_BUFFER. */ |
| 574 | switch (p->location) |
| 575 | { |
| 576 | case DWARF_VALUE_REGISTER: |
| 577 | { |
| 578 | struct gdbarch *arch = get_frame_arch (frame); |
| 579 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.value); |
| 580 | int reg_offset = source_offset; |
| 581 | |
| 582 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG |
| 583 | && this_size < register_size (arch, gdb_regnum)) |
| 584 | { |
| 585 | /* Big-endian, and we want less than full size. */ |
| 586 | reg_offset = register_size (arch, gdb_regnum) - this_size; |
| 587 | /* We want the lower-order THIS_SIZE_BITS of the bytes |
| 588 | we extract from the register. */ |
| 589 | source_offset_bits += 8 * this_size - this_size_bits; |
| 590 | } |
| 591 | |
| 592 | if (gdb_regnum != -1) |
| 593 | { |
| 594 | get_frame_register_bytes (frame, gdb_regnum, reg_offset, |
| 595 | this_size, buffer); |
| 596 | } |
| 597 | else |
| 598 | { |
| 599 | error (_("Unable to access DWARF register number %s"), |
| 600 | paddress (arch, p->v.value)); |
| 601 | } |
| 602 | } |
| 603 | break; |
| 604 | |
| 605 | case DWARF_VALUE_MEMORY: |
| 606 | read_value_memory (v, offset, |
| 607 | p->v.mem.in_stack_memory, |
| 608 | p->v.mem.addr + source_offset, |
| 609 | buffer, this_size); |
| 610 | break; |
| 611 | |
| 612 | case DWARF_VALUE_STACK: |
| 613 | { |
| 614 | struct gdbarch *gdbarch = get_type_arch (value_type (v)); |
| 615 | size_t n = this_size; |
| 616 | |
| 617 | if (n > c->addr_size - source_offset) |
| 618 | n = (c->addr_size >= source_offset |
| 619 | ? c->addr_size - source_offset |
| 620 | : 0); |
| 621 | if (n == 0) |
| 622 | { |
| 623 | /* Nothing. */ |
| 624 | } |
| 625 | else if (source_offset == 0) |
| 626 | store_unsigned_integer (buffer, n, |
| 627 | gdbarch_byte_order (gdbarch), |
| 628 | p->v.value); |
| 629 | else |
| 630 | { |
| 631 | gdb_byte bytes[sizeof (ULONGEST)]; |
| 632 | |
| 633 | store_unsigned_integer (bytes, n + source_offset, |
| 634 | gdbarch_byte_order (gdbarch), |
| 635 | p->v.value); |
| 636 | memcpy (buffer, bytes + source_offset, n); |
| 637 | } |
| 638 | } |
| 639 | break; |
| 640 | |
| 641 | case DWARF_VALUE_LITERAL: |
| 642 | { |
| 643 | size_t n = this_size; |
| 644 | |
| 645 | if (n > p->v.literal.length - source_offset) |
| 646 | n = (p->v.literal.length >= source_offset |
| 647 | ? p->v.literal.length - source_offset |
| 648 | : 0); |
| 649 | if (n != 0) |
| 650 | intermediate_buffer = p->v.literal.data + source_offset; |
| 651 | } |
| 652 | break; |
| 653 | |
| 654 | /* These bits show up as zeros -- but do not cause the value |
| 655 | to be considered optimized-out. */ |
| 656 | case DWARF_VALUE_IMPLICIT_POINTER: |
| 657 | break; |
| 658 | |
| 659 | case DWARF_VALUE_OPTIMIZED_OUT: |
| 660 | set_value_optimized_out (v, 1); |
| 661 | break; |
| 662 | |
| 663 | default: |
| 664 | internal_error (__FILE__, __LINE__, _("invalid location type")); |
| 665 | } |
| 666 | |
| 667 | if (p->location != DWARF_VALUE_OPTIMIZED_OUT |
| 668 | && p->location != DWARF_VALUE_IMPLICIT_POINTER) |
| 669 | copy_bitwise (contents, dest_offset_bits, |
| 670 | intermediate_buffer, source_offset_bits % 8, |
| 671 | this_size_bits, bits_big_endian); |
| 672 | |
| 673 | offset += this_size_bits; |
| 674 | } |
| 675 | |
| 676 | do_cleanups (cleanup); |
| 677 | } |
| 678 | |
| 679 | static void |
| 680 | write_pieced_value (struct value *to, struct value *from) |
| 681 | { |
| 682 | int i; |
| 683 | long offset = 0; |
| 684 | ULONGEST bits_to_skip; |
| 685 | const gdb_byte *contents; |
| 686 | struct piece_closure *c |
| 687 | = (struct piece_closure *) value_computed_closure (to); |
| 688 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (to)); |
| 689 | size_t type_len; |
| 690 | size_t buffer_size = 0; |
| 691 | char *buffer = NULL; |
| 692 | struct cleanup *cleanup; |
| 693 | int bits_big_endian |
| 694 | = gdbarch_bits_big_endian (get_type_arch (value_type (to))); |
| 695 | |
| 696 | if (frame == NULL) |
| 697 | { |
| 698 | set_value_optimized_out (to, 1); |
| 699 | return; |
| 700 | } |
| 701 | |
| 702 | cleanup = make_cleanup (free_current_contents, &buffer); |
| 703 | |
| 704 | contents = value_contents (from); |
| 705 | bits_to_skip = 8 * value_offset (to); |
| 706 | if (value_bitsize (to)) |
| 707 | { |
| 708 | bits_to_skip += value_bitpos (to); |
| 709 | type_len = value_bitsize (to); |
| 710 | } |
| 711 | else |
| 712 | type_len = 8 * TYPE_LENGTH (value_type (to)); |
| 713 | |
| 714 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
| 715 | { |
| 716 | struct dwarf_expr_piece *p = &c->pieces[i]; |
| 717 | size_t this_size_bits, this_size; |
| 718 | long dest_offset_bits, source_offset_bits, dest_offset, source_offset; |
| 719 | int need_bitwise; |
| 720 | const gdb_byte *source_buffer; |
| 721 | |
| 722 | this_size_bits = p->size; |
| 723 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) |
| 724 | { |
| 725 | bits_to_skip -= this_size_bits; |
| 726 | continue; |
| 727 | } |
| 728 | if (this_size_bits > type_len - offset) |
| 729 | this_size_bits = type_len - offset; |
| 730 | if (bits_to_skip > 0) |
| 731 | { |
| 732 | dest_offset_bits = bits_to_skip; |
| 733 | source_offset_bits = 0; |
| 734 | this_size_bits -= bits_to_skip; |
| 735 | bits_to_skip = 0; |
| 736 | } |
| 737 | else |
| 738 | { |
| 739 | dest_offset_bits = 0; |
| 740 | source_offset_bits = offset; |
| 741 | } |
| 742 | |
| 743 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; |
| 744 | source_offset = source_offset_bits / 8; |
| 745 | dest_offset = dest_offset_bits / 8; |
| 746 | if (dest_offset_bits % 8 == 0 && source_offset_bits % 8 == 0) |
| 747 | { |
| 748 | source_buffer = contents + source_offset; |
| 749 | need_bitwise = 0; |
| 750 | } |
| 751 | else |
| 752 | { |
| 753 | if (buffer_size < this_size) |
| 754 | { |
| 755 | buffer_size = this_size; |
| 756 | buffer = xrealloc (buffer, buffer_size); |
| 757 | } |
| 758 | source_buffer = buffer; |
| 759 | need_bitwise = 1; |
| 760 | } |
| 761 | |
| 762 | switch (p->location) |
| 763 | { |
| 764 | case DWARF_VALUE_REGISTER: |
| 765 | { |
| 766 | struct gdbarch *arch = get_frame_arch (frame); |
| 767 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.value); |
| 768 | int reg_offset = dest_offset; |
| 769 | |
| 770 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG |
| 771 | && this_size <= register_size (arch, gdb_regnum)) |
| 772 | /* Big-endian, and we want less than full size. */ |
| 773 | reg_offset = register_size (arch, gdb_regnum) - this_size; |
| 774 | |
| 775 | if (gdb_regnum != -1) |
| 776 | { |
| 777 | if (need_bitwise) |
| 778 | { |
| 779 | get_frame_register_bytes (frame, gdb_regnum, reg_offset, |
| 780 | this_size, buffer); |
| 781 | copy_bitwise (buffer, dest_offset_bits, |
| 782 | contents, source_offset_bits, |
| 783 | this_size_bits, |
| 784 | bits_big_endian); |
| 785 | } |
| 786 | |
| 787 | put_frame_register_bytes (frame, gdb_regnum, reg_offset, |
| 788 | this_size, source_buffer); |
| 789 | } |
| 790 | else |
| 791 | { |
| 792 | error (_("Unable to write to DWARF register number %s"), |
| 793 | paddress (arch, p->v.value)); |
| 794 | } |
| 795 | } |
| 796 | break; |
| 797 | case DWARF_VALUE_MEMORY: |
| 798 | if (need_bitwise) |
| 799 | { |
| 800 | /* Only the first and last bytes can possibly have any |
| 801 | bits reused. */ |
| 802 | read_memory (p->v.mem.addr + dest_offset, buffer, 1); |
| 803 | read_memory (p->v.mem.addr + dest_offset + this_size - 1, |
| 804 | buffer + this_size - 1, 1); |
| 805 | copy_bitwise (buffer, dest_offset_bits, |
| 806 | contents, source_offset_bits, |
| 807 | this_size_bits, |
| 808 | bits_big_endian); |
| 809 | } |
| 810 | |
| 811 | write_memory (p->v.mem.addr + dest_offset, |
| 812 | source_buffer, this_size); |
| 813 | break; |
| 814 | default: |
| 815 | set_value_optimized_out (to, 1); |
| 816 | break; |
| 817 | } |
| 818 | offset += this_size_bits; |
| 819 | } |
| 820 | |
| 821 | do_cleanups (cleanup); |
| 822 | } |
| 823 | |
| 824 | /* A helper function that checks bit validity in a pieced value. |
| 825 | CHECK_FOR indicates the kind of validity checking. |
| 826 | DWARF_VALUE_MEMORY means to check whether any bit is valid. |
| 827 | DWARF_VALUE_OPTIMIZED_OUT means to check whether any bit is |
| 828 | optimized out. |
| 829 | DWARF_VALUE_IMPLICIT_POINTER means to check whether the bits are an |
| 830 | implicit pointer. */ |
| 831 | |
| 832 | static int |
| 833 | check_pieced_value_bits (const struct value *value, int bit_offset, |
| 834 | int bit_length, |
| 835 | enum dwarf_value_location check_for) |
| 836 | { |
| 837 | struct piece_closure *c |
| 838 | = (struct piece_closure *) value_computed_closure (value); |
| 839 | int i; |
| 840 | int validity = (check_for == DWARF_VALUE_MEMORY |
| 841 | || check_for == DWARF_VALUE_IMPLICIT_POINTER); |
| 842 | |
| 843 | bit_offset += 8 * value_offset (value); |
| 844 | if (value_bitsize (value)) |
| 845 | bit_offset += value_bitpos (value); |
| 846 | |
| 847 | for (i = 0; i < c->n_pieces && bit_length > 0; i++) |
| 848 | { |
| 849 | struct dwarf_expr_piece *p = &c->pieces[i]; |
| 850 | size_t this_size_bits = p->size; |
| 851 | |
| 852 | if (bit_offset > 0) |
| 853 | { |
| 854 | if (bit_offset >= this_size_bits) |
| 855 | { |
| 856 | bit_offset -= this_size_bits; |
| 857 | continue; |
| 858 | } |
| 859 | |
| 860 | bit_length -= this_size_bits - bit_offset; |
| 861 | bit_offset = 0; |
| 862 | } |
| 863 | else |
| 864 | bit_length -= this_size_bits; |
| 865 | |
| 866 | if (check_for == DWARF_VALUE_IMPLICIT_POINTER) |
| 867 | { |
| 868 | if (p->location != DWARF_VALUE_IMPLICIT_POINTER) |
| 869 | return 0; |
| 870 | } |
| 871 | else if (p->location == DWARF_VALUE_OPTIMIZED_OUT |
| 872 | || p->location == DWARF_VALUE_IMPLICIT_POINTER) |
| 873 | { |
| 874 | if (validity) |
| 875 | return 0; |
| 876 | } |
| 877 | else |
| 878 | { |
| 879 | if (!validity) |
| 880 | return 1; |
| 881 | } |
| 882 | } |
| 883 | |
| 884 | return validity; |
| 885 | } |
| 886 | |
| 887 | static int |
| 888 | check_pieced_value_validity (const struct value *value, int bit_offset, |
| 889 | int bit_length) |
| 890 | { |
| 891 | return check_pieced_value_bits (value, bit_offset, bit_length, |
| 892 | DWARF_VALUE_MEMORY); |
| 893 | } |
| 894 | |
| 895 | static int |
| 896 | check_pieced_value_invalid (const struct value *value) |
| 897 | { |
| 898 | return check_pieced_value_bits (value, 0, |
| 899 | 8 * TYPE_LENGTH (value_type (value)), |
| 900 | DWARF_VALUE_OPTIMIZED_OUT); |
| 901 | } |
| 902 | |
| 903 | /* An implementation of an lval_funcs method to see whether a value is |
| 904 | a synthetic pointer. */ |
| 905 | |
| 906 | static int |
| 907 | check_pieced_synthetic_pointer (const struct value *value, int bit_offset, |
| 908 | int bit_length) |
| 909 | { |
| 910 | return check_pieced_value_bits (value, bit_offset, bit_length, |
| 911 | DWARF_VALUE_IMPLICIT_POINTER); |
| 912 | } |
| 913 | |
| 914 | /* A wrapper function for get_frame_address_in_block. */ |
| 915 | |
| 916 | static CORE_ADDR |
| 917 | get_frame_address_in_block_wrapper (void *baton) |
| 918 | { |
| 919 | return get_frame_address_in_block (baton); |
| 920 | } |
| 921 | |
| 922 | /* An implementation of an lval_funcs method to indirect through a |
| 923 | pointer. This handles the synthetic pointer case when needed. */ |
| 924 | |
| 925 | static struct value * |
| 926 | indirect_pieced_value (struct value *value) |
| 927 | { |
| 928 | struct piece_closure *c |
| 929 | = (struct piece_closure *) value_computed_closure (value); |
| 930 | struct type *type; |
| 931 | struct frame_info *frame; |
| 932 | struct dwarf2_locexpr_baton baton; |
| 933 | int i, bit_offset, bit_length; |
| 934 | struct dwarf_expr_piece *piece = NULL; |
| 935 | struct value *result; |
| 936 | LONGEST byte_offset; |
| 937 | |
| 938 | type = value_type (value); |
| 939 | if (TYPE_CODE (type) != TYPE_CODE_PTR) |
| 940 | return NULL; |
| 941 | |
| 942 | bit_length = 8 * TYPE_LENGTH (type); |
| 943 | bit_offset = 8 * value_offset (value); |
| 944 | if (value_bitsize (value)) |
| 945 | bit_offset += value_bitpos (value); |
| 946 | |
| 947 | for (i = 0; i < c->n_pieces && bit_length > 0; i++) |
| 948 | { |
| 949 | struct dwarf_expr_piece *p = &c->pieces[i]; |
| 950 | size_t this_size_bits = p->size; |
| 951 | |
| 952 | if (bit_offset > 0) |
| 953 | { |
| 954 | if (bit_offset >= this_size_bits) |
| 955 | { |
| 956 | bit_offset -= this_size_bits; |
| 957 | continue; |
| 958 | } |
| 959 | |
| 960 | bit_length -= this_size_bits - bit_offset; |
| 961 | bit_offset = 0; |
| 962 | } |
| 963 | else |
| 964 | bit_length -= this_size_bits; |
| 965 | |
| 966 | if (p->location != DWARF_VALUE_IMPLICIT_POINTER) |
| 967 | return NULL; |
| 968 | |
| 969 | if (bit_length != 0) |
| 970 | error (_("Invalid use of DW_OP_GNU_implicit_pointer")); |
| 971 | |
| 972 | piece = p; |
| 973 | break; |
| 974 | } |
| 975 | |
| 976 | frame = get_selected_frame (_("No frame selected.")); |
| 977 | byte_offset = value_as_address (value); |
| 978 | |
| 979 | gdb_assert (piece); |
| 980 | baton = dwarf2_fetch_die_location_block (piece->v.ptr.die, c->per_cu, |
| 981 | get_frame_address_in_block_wrapper, |
| 982 | frame); |
| 983 | |
| 984 | result = dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type), frame, |
| 985 | baton.data, baton.size, baton.per_cu, |
| 986 | byte_offset); |
| 987 | |
| 988 | return result; |
| 989 | } |
| 990 | |
| 991 | static void * |
| 992 | copy_pieced_value_closure (const struct value *v) |
| 993 | { |
| 994 | struct piece_closure *c |
| 995 | = (struct piece_closure *) value_computed_closure (v); |
| 996 | |
| 997 | ++c->refc; |
| 998 | return c; |
| 999 | } |
| 1000 | |
| 1001 | static void |
| 1002 | free_pieced_value_closure (struct value *v) |
| 1003 | { |
| 1004 | struct piece_closure *c |
| 1005 | = (struct piece_closure *) value_computed_closure (v); |
| 1006 | |
| 1007 | --c->refc; |
| 1008 | if (c->refc == 0) |
| 1009 | { |
| 1010 | xfree (c->pieces); |
| 1011 | xfree (c); |
| 1012 | } |
| 1013 | } |
| 1014 | |
| 1015 | /* Functions for accessing a variable described by DW_OP_piece. */ |
| 1016 | static struct lval_funcs pieced_value_funcs = { |
| 1017 | read_pieced_value, |
| 1018 | write_pieced_value, |
| 1019 | check_pieced_value_validity, |
| 1020 | check_pieced_value_invalid, |
| 1021 | indirect_pieced_value, |
| 1022 | check_pieced_synthetic_pointer, |
| 1023 | copy_pieced_value_closure, |
| 1024 | free_pieced_value_closure |
| 1025 | }; |
| 1026 | |
| 1027 | /* Helper function which throws an error if a synthetic pointer is |
| 1028 | invalid. */ |
| 1029 | |
| 1030 | static void |
| 1031 | invalid_synthetic_pointer (void) |
| 1032 | { |
| 1033 | error (_("access outside bounds of object " |
| 1034 | "referenced via synthetic pointer")); |
| 1035 | } |
| 1036 | |
| 1037 | /* Evaluate a location description, starting at DATA and with length |
| 1038 | SIZE, to find the current location of variable of TYPE in the |
| 1039 | context of FRAME. BYTE_OFFSET is applied after the contents are |
| 1040 | computed. */ |
| 1041 | |
| 1042 | static struct value * |
| 1043 | dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame, |
| 1044 | const gdb_byte *data, unsigned short size, |
| 1045 | struct dwarf2_per_cu_data *per_cu, |
| 1046 | LONGEST byte_offset) |
| 1047 | { |
| 1048 | struct value *retval; |
| 1049 | struct dwarf_expr_baton baton; |
| 1050 | struct dwarf_expr_context *ctx; |
| 1051 | struct cleanup *old_chain; |
| 1052 | struct objfile *objfile = dwarf2_per_cu_objfile (per_cu); |
| 1053 | |
| 1054 | if (byte_offset < 0) |
| 1055 | invalid_synthetic_pointer (); |
| 1056 | |
| 1057 | if (size == 0) |
| 1058 | { |
| 1059 | retval = allocate_value (type); |
| 1060 | VALUE_LVAL (retval) = not_lval; |
| 1061 | set_value_optimized_out (retval, 1); |
| 1062 | return retval; |
| 1063 | } |
| 1064 | |
| 1065 | baton.frame = frame; |
| 1066 | baton.per_cu = per_cu; |
| 1067 | |
| 1068 | ctx = new_dwarf_expr_context (); |
| 1069 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
| 1070 | |
| 1071 | ctx->gdbarch = get_objfile_arch (objfile); |
| 1072 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
| 1073 | ctx->offset = dwarf2_per_cu_text_offset (per_cu); |
| 1074 | ctx->baton = &baton; |
| 1075 | ctx->read_reg = dwarf_expr_read_reg; |
| 1076 | ctx->read_mem = dwarf_expr_read_mem; |
| 1077 | ctx->get_frame_base = dwarf_expr_frame_base; |
| 1078 | ctx->get_frame_cfa = dwarf_expr_frame_cfa; |
| 1079 | ctx->get_frame_pc = dwarf_expr_frame_pc; |
| 1080 | ctx->get_tls_address = dwarf_expr_tls_address; |
| 1081 | ctx->dwarf_call = dwarf_expr_dwarf_call; |
| 1082 | |
| 1083 | dwarf_expr_eval (ctx, data, size); |
| 1084 | if (ctx->num_pieces > 0) |
| 1085 | { |
| 1086 | struct piece_closure *c; |
| 1087 | struct frame_id frame_id = get_frame_id (frame); |
| 1088 | ULONGEST bit_size = 0; |
| 1089 | int i; |
| 1090 | |
| 1091 | for (i = 0; i < ctx->num_pieces; ++i) |
| 1092 | bit_size += ctx->pieces[i].size; |
| 1093 | if (8 * (byte_offset + TYPE_LENGTH (type)) > bit_size) |
| 1094 | invalid_synthetic_pointer (); |
| 1095 | |
| 1096 | c = allocate_piece_closure (per_cu, ctx->num_pieces, ctx->pieces, |
| 1097 | ctx->addr_size); |
| 1098 | retval = allocate_computed_value (type, &pieced_value_funcs, c); |
| 1099 | VALUE_FRAME_ID (retval) = frame_id; |
| 1100 | set_value_offset (retval, byte_offset); |
| 1101 | } |
| 1102 | else |
| 1103 | { |
| 1104 | switch (ctx->location) |
| 1105 | { |
| 1106 | case DWARF_VALUE_REGISTER: |
| 1107 | { |
| 1108 | struct gdbarch *arch = get_frame_arch (frame); |
| 1109 | ULONGEST dwarf_regnum = dwarf_expr_fetch (ctx, 0); |
| 1110 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_regnum); |
| 1111 | |
| 1112 | if (byte_offset != 0) |
| 1113 | error (_("cannot use offset on synthetic pointer to register")); |
| 1114 | if (gdb_regnum != -1) |
| 1115 | retval = value_from_register (type, gdb_regnum, frame); |
| 1116 | else |
| 1117 | error (_("Unable to access DWARF register number %s"), |
| 1118 | paddress (arch, dwarf_regnum)); |
| 1119 | } |
| 1120 | break; |
| 1121 | |
| 1122 | case DWARF_VALUE_MEMORY: |
| 1123 | { |
| 1124 | CORE_ADDR address = dwarf_expr_fetch_address (ctx, 0); |
| 1125 | int in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0); |
| 1126 | |
| 1127 | retval = allocate_value_lazy (type); |
| 1128 | VALUE_LVAL (retval) = lval_memory; |
| 1129 | if (in_stack_memory) |
| 1130 | set_value_stack (retval, 1); |
| 1131 | set_value_address (retval, address + byte_offset); |
| 1132 | } |
| 1133 | break; |
| 1134 | |
| 1135 | case DWARF_VALUE_STACK: |
| 1136 | { |
| 1137 | ULONGEST value = dwarf_expr_fetch (ctx, 0); |
| 1138 | bfd_byte *contents, *tem; |
| 1139 | size_t n = ctx->addr_size; |
| 1140 | |
| 1141 | if (byte_offset + TYPE_LENGTH (type) > n) |
| 1142 | invalid_synthetic_pointer (); |
| 1143 | |
| 1144 | tem = alloca (n); |
| 1145 | store_unsigned_integer (tem, n, |
| 1146 | gdbarch_byte_order (ctx->gdbarch), |
| 1147 | value); |
| 1148 | |
| 1149 | tem += byte_offset; |
| 1150 | n -= byte_offset; |
| 1151 | |
| 1152 | retval = allocate_value (type); |
| 1153 | contents = value_contents_raw (retval); |
| 1154 | if (n > TYPE_LENGTH (type)) |
| 1155 | n = TYPE_LENGTH (type); |
| 1156 | memcpy (contents, tem, n); |
| 1157 | } |
| 1158 | break; |
| 1159 | |
| 1160 | case DWARF_VALUE_LITERAL: |
| 1161 | { |
| 1162 | bfd_byte *contents; |
| 1163 | const bfd_byte *ldata; |
| 1164 | size_t n = ctx->len; |
| 1165 | |
| 1166 | if (byte_offset + TYPE_LENGTH (type) > n) |
| 1167 | invalid_synthetic_pointer (); |
| 1168 | |
| 1169 | retval = allocate_value (type); |
| 1170 | contents = value_contents_raw (retval); |
| 1171 | |
| 1172 | ldata = ctx->data + byte_offset; |
| 1173 | n -= byte_offset; |
| 1174 | |
| 1175 | if (n > TYPE_LENGTH (type)) |
| 1176 | n = TYPE_LENGTH (type); |
| 1177 | memcpy (contents, ldata, n); |
| 1178 | } |
| 1179 | break; |
| 1180 | |
| 1181 | /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced |
| 1182 | operation by execute_stack_op. */ |
| 1183 | case DWARF_VALUE_IMPLICIT_POINTER: |
| 1184 | /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context -- |
| 1185 | it can only be encountered when making a piece. */ |
| 1186 | case DWARF_VALUE_OPTIMIZED_OUT: |
| 1187 | default: |
| 1188 | internal_error (__FILE__, __LINE__, _("invalid location type")); |
| 1189 | } |
| 1190 | } |
| 1191 | |
| 1192 | set_value_initialized (retval, ctx->initialized); |
| 1193 | |
| 1194 | do_cleanups (old_chain); |
| 1195 | |
| 1196 | return retval; |
| 1197 | } |
| 1198 | |
| 1199 | /* The exported interface to dwarf2_evaluate_loc_desc_full; it always |
| 1200 | passes 0 as the byte_offset. */ |
| 1201 | |
| 1202 | struct value * |
| 1203 | dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame, |
| 1204 | const gdb_byte *data, unsigned short size, |
| 1205 | struct dwarf2_per_cu_data *per_cu) |
| 1206 | { |
| 1207 | return dwarf2_evaluate_loc_desc_full (type, frame, data, size, per_cu, 0); |
| 1208 | } |
| 1209 | |
| 1210 | \f |
| 1211 | /* Helper functions and baton for dwarf2_loc_desc_needs_frame. */ |
| 1212 | |
| 1213 | struct needs_frame_baton |
| 1214 | { |
| 1215 | int needs_frame; |
| 1216 | struct dwarf2_per_cu_data *per_cu; |
| 1217 | }; |
| 1218 | |
| 1219 | /* Reads from registers do require a frame. */ |
| 1220 | static CORE_ADDR |
| 1221 | needs_frame_read_reg (void *baton, int regnum) |
| 1222 | { |
| 1223 | struct needs_frame_baton *nf_baton = baton; |
| 1224 | |
| 1225 | nf_baton->needs_frame = 1; |
| 1226 | return 1; |
| 1227 | } |
| 1228 | |
| 1229 | /* Reads from memory do not require a frame. */ |
| 1230 | static void |
| 1231 | needs_frame_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
| 1232 | { |
| 1233 | memset (buf, 0, len); |
| 1234 | } |
| 1235 | |
| 1236 | /* Frame-relative accesses do require a frame. */ |
| 1237 | static void |
| 1238 | needs_frame_frame_base (void *baton, const gdb_byte **start, size_t * length) |
| 1239 | { |
| 1240 | static gdb_byte lit0 = DW_OP_lit0; |
| 1241 | struct needs_frame_baton *nf_baton = baton; |
| 1242 | |
| 1243 | *start = &lit0; |
| 1244 | *length = 1; |
| 1245 | |
| 1246 | nf_baton->needs_frame = 1; |
| 1247 | } |
| 1248 | |
| 1249 | /* CFA accesses require a frame. */ |
| 1250 | |
| 1251 | static CORE_ADDR |
| 1252 | needs_frame_frame_cfa (void *baton) |
| 1253 | { |
| 1254 | struct needs_frame_baton *nf_baton = baton; |
| 1255 | |
| 1256 | nf_baton->needs_frame = 1; |
| 1257 | return 1; |
| 1258 | } |
| 1259 | |
| 1260 | /* Thread-local accesses do require a frame. */ |
| 1261 | static CORE_ADDR |
| 1262 | needs_frame_tls_address (void *baton, CORE_ADDR offset) |
| 1263 | { |
| 1264 | struct needs_frame_baton *nf_baton = baton; |
| 1265 | |
| 1266 | nf_baton->needs_frame = 1; |
| 1267 | return 1; |
| 1268 | } |
| 1269 | |
| 1270 | /* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame. */ |
| 1271 | |
| 1272 | static void |
| 1273 | needs_frame_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset) |
| 1274 | { |
| 1275 | struct needs_frame_baton *nf_baton = ctx->baton; |
| 1276 | |
| 1277 | return per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu, |
| 1278 | ctx->get_frame_pc, ctx->baton); |
| 1279 | } |
| 1280 | |
| 1281 | /* Return non-zero iff the location expression at DATA (length SIZE) |
| 1282 | requires a frame to evaluate. */ |
| 1283 | |
| 1284 | static int |
| 1285 | dwarf2_loc_desc_needs_frame (const gdb_byte *data, unsigned short size, |
| 1286 | struct dwarf2_per_cu_data *per_cu) |
| 1287 | { |
| 1288 | struct needs_frame_baton baton; |
| 1289 | struct dwarf_expr_context *ctx; |
| 1290 | int in_reg; |
| 1291 | struct cleanup *old_chain; |
| 1292 | struct objfile *objfile = dwarf2_per_cu_objfile (per_cu); |
| 1293 | |
| 1294 | baton.needs_frame = 0; |
| 1295 | baton.per_cu = per_cu; |
| 1296 | |
| 1297 | ctx = new_dwarf_expr_context (); |
| 1298 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
| 1299 | |
| 1300 | ctx->gdbarch = get_objfile_arch (objfile); |
| 1301 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
| 1302 | ctx->offset = dwarf2_per_cu_text_offset (per_cu); |
| 1303 | ctx->baton = &baton; |
| 1304 | ctx->read_reg = needs_frame_read_reg; |
| 1305 | ctx->read_mem = needs_frame_read_mem; |
| 1306 | ctx->get_frame_base = needs_frame_frame_base; |
| 1307 | ctx->get_frame_cfa = needs_frame_frame_cfa; |
| 1308 | ctx->get_frame_pc = needs_frame_frame_cfa; |
| 1309 | ctx->get_tls_address = needs_frame_tls_address; |
| 1310 | ctx->dwarf_call = needs_frame_dwarf_call; |
| 1311 | |
| 1312 | dwarf_expr_eval (ctx, data, size); |
| 1313 | |
| 1314 | in_reg = ctx->location == DWARF_VALUE_REGISTER; |
| 1315 | |
| 1316 | if (ctx->num_pieces > 0) |
| 1317 | { |
| 1318 | int i; |
| 1319 | |
| 1320 | /* If the location has several pieces, and any of them are in |
| 1321 | registers, then we will need a frame to fetch them from. */ |
| 1322 | for (i = 0; i < ctx->num_pieces; i++) |
| 1323 | if (ctx->pieces[i].location == DWARF_VALUE_REGISTER) |
| 1324 | in_reg = 1; |
| 1325 | } |
| 1326 | |
| 1327 | do_cleanups (old_chain); |
| 1328 | |
| 1329 | return baton.needs_frame || in_reg; |
| 1330 | } |
| 1331 | |
| 1332 | /* A helper function that throws an unimplemented error mentioning a |
| 1333 | given DWARF operator. */ |
| 1334 | |
| 1335 | static void |
| 1336 | unimplemented (unsigned int op) |
| 1337 | { |
| 1338 | const char *name = dwarf_stack_op_name (op); |
| 1339 | |
| 1340 | if (name) |
| 1341 | error (_("DWARF operator %s cannot be translated to an agent expression"), |
| 1342 | name); |
| 1343 | else |
| 1344 | error (_("Unknown DWARF operator 0x%02x cannot be translated " |
| 1345 | "to an agent expression"), |
| 1346 | op); |
| 1347 | } |
| 1348 | |
| 1349 | /* A helper function to convert a DWARF register to an arch register. |
| 1350 | ARCH is the architecture. |
| 1351 | DWARF_REG is the register. |
| 1352 | This will throw an exception if the DWARF register cannot be |
| 1353 | translated to an architecture register. */ |
| 1354 | |
| 1355 | static int |
| 1356 | translate_register (struct gdbarch *arch, int dwarf_reg) |
| 1357 | { |
| 1358 | int reg = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_reg); |
| 1359 | if (reg == -1) |
| 1360 | error (_("Unable to access DWARF register number %d"), dwarf_reg); |
| 1361 | return reg; |
| 1362 | } |
| 1363 | |
| 1364 | /* A helper function that emits an access to memory. ARCH is the |
| 1365 | target architecture. EXPR is the expression which we are building. |
| 1366 | NBITS is the number of bits we want to read. This emits the |
| 1367 | opcodes needed to read the memory and then extract the desired |
| 1368 | bits. */ |
| 1369 | |
| 1370 | static void |
| 1371 | access_memory (struct gdbarch *arch, struct agent_expr *expr, ULONGEST nbits) |
| 1372 | { |
| 1373 | ULONGEST nbytes = (nbits + 7) / 8; |
| 1374 | |
| 1375 | gdb_assert (nbits > 0 && nbits <= sizeof (LONGEST)); |
| 1376 | |
| 1377 | if (trace_kludge) |
| 1378 | ax_trace_quick (expr, nbytes); |
| 1379 | |
| 1380 | if (nbits <= 8) |
| 1381 | ax_simple (expr, aop_ref8); |
| 1382 | else if (nbits <= 16) |
| 1383 | ax_simple (expr, aop_ref16); |
| 1384 | else if (nbits <= 32) |
| 1385 | ax_simple (expr, aop_ref32); |
| 1386 | else |
| 1387 | ax_simple (expr, aop_ref64); |
| 1388 | |
| 1389 | /* If we read exactly the number of bytes we wanted, we're done. */ |
| 1390 | if (8 * nbytes == nbits) |
| 1391 | return; |
| 1392 | |
| 1393 | if (gdbarch_bits_big_endian (arch)) |
| 1394 | { |
| 1395 | /* On a bits-big-endian machine, we want the high-order |
| 1396 | NBITS. */ |
| 1397 | ax_const_l (expr, 8 * nbytes - nbits); |
| 1398 | ax_simple (expr, aop_rsh_unsigned); |
| 1399 | } |
| 1400 | else |
| 1401 | { |
| 1402 | /* On a bits-little-endian box, we want the low-order NBITS. */ |
| 1403 | ax_zero_ext (expr, nbits); |
| 1404 | } |
| 1405 | } |
| 1406 | |
| 1407 | /* A helper function to return the frame's PC. */ |
| 1408 | |
| 1409 | static CORE_ADDR |
| 1410 | get_ax_pc (void *baton) |
| 1411 | { |
| 1412 | struct agent_expr *expr = baton; |
| 1413 | |
| 1414 | return expr->scope; |
| 1415 | } |
| 1416 | |
| 1417 | /* Compile a DWARF location expression to an agent expression. |
| 1418 | |
| 1419 | EXPR is the agent expression we are building. |
| 1420 | LOC is the agent value we modify. |
| 1421 | ARCH is the architecture. |
| 1422 | ADDR_SIZE is the size of addresses, in bytes. |
| 1423 | OP_PTR is the start of the location expression. |
| 1424 | OP_END is one past the last byte of the location expression. |
| 1425 | |
| 1426 | This will throw an exception for various kinds of errors -- for |
| 1427 | example, if the expression cannot be compiled, or if the expression |
| 1428 | is invalid. */ |
| 1429 | |
| 1430 | void |
| 1431 | dwarf2_compile_expr_to_ax (struct agent_expr *expr, struct axs_value *loc, |
| 1432 | struct gdbarch *arch, unsigned int addr_size, |
| 1433 | const gdb_byte *op_ptr, const gdb_byte *op_end, |
| 1434 | struct dwarf2_per_cu_data *per_cu) |
| 1435 | { |
| 1436 | struct cleanup *cleanups; |
| 1437 | int i, *offsets; |
| 1438 | VEC(int) *dw_labels = NULL, *patches = NULL; |
| 1439 | const gdb_byte * const base = op_ptr; |
| 1440 | const gdb_byte *previous_piece = op_ptr; |
| 1441 | enum bfd_endian byte_order = gdbarch_byte_order (arch); |
| 1442 | ULONGEST bits_collected = 0; |
| 1443 | unsigned int addr_size_bits = 8 * addr_size; |
| 1444 | int bits_big_endian = gdbarch_bits_big_endian (arch); |
| 1445 | |
| 1446 | offsets = xmalloc ((op_end - op_ptr) * sizeof (int)); |
| 1447 | cleanups = make_cleanup (xfree, offsets); |
| 1448 | |
| 1449 | for (i = 0; i < op_end - op_ptr; ++i) |
| 1450 | offsets[i] = -1; |
| 1451 | |
| 1452 | make_cleanup (VEC_cleanup (int), &dw_labels); |
| 1453 | make_cleanup (VEC_cleanup (int), &patches); |
| 1454 | |
| 1455 | /* By default we are making an address. */ |
| 1456 | loc->kind = axs_lvalue_memory; |
| 1457 | |
| 1458 | while (op_ptr < op_end) |
| 1459 | { |
| 1460 | enum dwarf_location_atom op = *op_ptr; |
| 1461 | ULONGEST uoffset, reg; |
| 1462 | LONGEST offset; |
| 1463 | int i; |
| 1464 | |
| 1465 | offsets[op_ptr - base] = expr->len; |
| 1466 | ++op_ptr; |
| 1467 | |
| 1468 | /* Our basic approach to code generation is to map DWARF |
| 1469 | operations directly to AX operations. However, there are |
| 1470 | some differences. |
| 1471 | |
| 1472 | First, DWARF works on address-sized units, but AX always uses |
| 1473 | LONGEST. For most operations we simply ignore this |
| 1474 | difference; instead we generate sign extensions as needed |
| 1475 | before division and comparison operations. It would be nice |
| 1476 | to omit the sign extensions, but there is no way to determine |
| 1477 | the size of the target's LONGEST. (This code uses the size |
| 1478 | of the host LONGEST in some cases -- that is a bug but it is |
| 1479 | difficult to fix.) |
| 1480 | |
| 1481 | Second, some DWARF operations cannot be translated to AX. |
| 1482 | For these we simply fail. See |
| 1483 | http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */ |
| 1484 | switch (op) |
| 1485 | { |
| 1486 | case DW_OP_lit0: |
| 1487 | case DW_OP_lit1: |
| 1488 | case DW_OP_lit2: |
| 1489 | case DW_OP_lit3: |
| 1490 | case DW_OP_lit4: |
| 1491 | case DW_OP_lit5: |
| 1492 | case DW_OP_lit6: |
| 1493 | case DW_OP_lit7: |
| 1494 | case DW_OP_lit8: |
| 1495 | case DW_OP_lit9: |
| 1496 | case DW_OP_lit10: |
| 1497 | case DW_OP_lit11: |
| 1498 | case DW_OP_lit12: |
| 1499 | case DW_OP_lit13: |
| 1500 | case DW_OP_lit14: |
| 1501 | case DW_OP_lit15: |
| 1502 | case DW_OP_lit16: |
| 1503 | case DW_OP_lit17: |
| 1504 | case DW_OP_lit18: |
| 1505 | case DW_OP_lit19: |
| 1506 | case DW_OP_lit20: |
| 1507 | case DW_OP_lit21: |
| 1508 | case DW_OP_lit22: |
| 1509 | case DW_OP_lit23: |
| 1510 | case DW_OP_lit24: |
| 1511 | case DW_OP_lit25: |
| 1512 | case DW_OP_lit26: |
| 1513 | case DW_OP_lit27: |
| 1514 | case DW_OP_lit28: |
| 1515 | case DW_OP_lit29: |
| 1516 | case DW_OP_lit30: |
| 1517 | case DW_OP_lit31: |
| 1518 | ax_const_l (expr, op - DW_OP_lit0); |
| 1519 | break; |
| 1520 | |
| 1521 | case DW_OP_addr: |
| 1522 | uoffset = extract_unsigned_integer (op_ptr, addr_size, byte_order); |
| 1523 | op_ptr += addr_size; |
| 1524 | /* Some versions of GCC emit DW_OP_addr before |
| 1525 | DW_OP_GNU_push_tls_address. In this case the value is an |
| 1526 | index, not an address. We don't support things like |
| 1527 | branching between the address and the TLS op. */ |
| 1528 | if (op_ptr >= op_end || *op_ptr != DW_OP_GNU_push_tls_address) |
| 1529 | uoffset += dwarf2_per_cu_text_offset (per_cu); |
| 1530 | ax_const_l (expr, uoffset); |
| 1531 | break; |
| 1532 | |
| 1533 | case DW_OP_const1u: |
| 1534 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 1, byte_order)); |
| 1535 | op_ptr += 1; |
| 1536 | break; |
| 1537 | case DW_OP_const1s: |
| 1538 | ax_const_l (expr, extract_signed_integer (op_ptr, 1, byte_order)); |
| 1539 | op_ptr += 1; |
| 1540 | break; |
| 1541 | case DW_OP_const2u: |
| 1542 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 2, byte_order)); |
| 1543 | op_ptr += 2; |
| 1544 | break; |
| 1545 | case DW_OP_const2s: |
| 1546 | ax_const_l (expr, extract_signed_integer (op_ptr, 2, byte_order)); |
| 1547 | op_ptr += 2; |
| 1548 | break; |
| 1549 | case DW_OP_const4u: |
| 1550 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 4, byte_order)); |
| 1551 | op_ptr += 4; |
| 1552 | break; |
| 1553 | case DW_OP_const4s: |
| 1554 | ax_const_l (expr, extract_signed_integer (op_ptr, 4, byte_order)); |
| 1555 | op_ptr += 4; |
| 1556 | break; |
| 1557 | case DW_OP_const8u: |
| 1558 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 8, byte_order)); |
| 1559 | op_ptr += 8; |
| 1560 | break; |
| 1561 | case DW_OP_const8s: |
| 1562 | ax_const_l (expr, extract_signed_integer (op_ptr, 8, byte_order)); |
| 1563 | op_ptr += 8; |
| 1564 | break; |
| 1565 | case DW_OP_constu: |
| 1566 | op_ptr = read_uleb128 (op_ptr, op_end, &uoffset); |
| 1567 | ax_const_l (expr, uoffset); |
| 1568 | break; |
| 1569 | case DW_OP_consts: |
| 1570 | op_ptr = read_sleb128 (op_ptr, op_end, &offset); |
| 1571 | ax_const_l (expr, offset); |
| 1572 | break; |
| 1573 | |
| 1574 | case DW_OP_reg0: |
| 1575 | case DW_OP_reg1: |
| 1576 | case DW_OP_reg2: |
| 1577 | case DW_OP_reg3: |
| 1578 | case DW_OP_reg4: |
| 1579 | case DW_OP_reg5: |
| 1580 | case DW_OP_reg6: |
| 1581 | case DW_OP_reg7: |
| 1582 | case DW_OP_reg8: |
| 1583 | case DW_OP_reg9: |
| 1584 | case DW_OP_reg10: |
| 1585 | case DW_OP_reg11: |
| 1586 | case DW_OP_reg12: |
| 1587 | case DW_OP_reg13: |
| 1588 | case DW_OP_reg14: |
| 1589 | case DW_OP_reg15: |
| 1590 | case DW_OP_reg16: |
| 1591 | case DW_OP_reg17: |
| 1592 | case DW_OP_reg18: |
| 1593 | case DW_OP_reg19: |
| 1594 | case DW_OP_reg20: |
| 1595 | case DW_OP_reg21: |
| 1596 | case DW_OP_reg22: |
| 1597 | case DW_OP_reg23: |
| 1598 | case DW_OP_reg24: |
| 1599 | case DW_OP_reg25: |
| 1600 | case DW_OP_reg26: |
| 1601 | case DW_OP_reg27: |
| 1602 | case DW_OP_reg28: |
| 1603 | case DW_OP_reg29: |
| 1604 | case DW_OP_reg30: |
| 1605 | case DW_OP_reg31: |
| 1606 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx"); |
| 1607 | loc->u.reg = translate_register (arch, op - DW_OP_reg0); |
| 1608 | loc->kind = axs_lvalue_register; |
| 1609 | break; |
| 1610 | |
| 1611 | case DW_OP_regx: |
| 1612 | op_ptr = read_uleb128 (op_ptr, op_end, ®); |
| 1613 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx"); |
| 1614 | loc->u.reg = translate_register (arch, reg); |
| 1615 | loc->kind = axs_lvalue_register; |
| 1616 | break; |
| 1617 | |
| 1618 | case DW_OP_implicit_value: |
| 1619 | { |
| 1620 | ULONGEST len; |
| 1621 | |
| 1622 | op_ptr = read_uleb128 (op_ptr, op_end, &len); |
| 1623 | if (op_ptr + len > op_end) |
| 1624 | error (_("DW_OP_implicit_value: too few bytes available.")); |
| 1625 | if (len > sizeof (ULONGEST)) |
| 1626 | error (_("Cannot translate DW_OP_implicit_value of %d bytes"), |
| 1627 | (int) len); |
| 1628 | |
| 1629 | ax_const_l (expr, extract_unsigned_integer (op_ptr, len, |
| 1630 | byte_order)); |
| 1631 | op_ptr += len; |
| 1632 | dwarf_expr_require_composition (op_ptr, op_end, |
| 1633 | "DW_OP_implicit_value"); |
| 1634 | |
| 1635 | loc->kind = axs_rvalue; |
| 1636 | } |
| 1637 | break; |
| 1638 | |
| 1639 | case DW_OP_stack_value: |
| 1640 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value"); |
| 1641 | loc->kind = axs_rvalue; |
| 1642 | break; |
| 1643 | |
| 1644 | case DW_OP_breg0: |
| 1645 | case DW_OP_breg1: |
| 1646 | case DW_OP_breg2: |
| 1647 | case DW_OP_breg3: |
| 1648 | case DW_OP_breg4: |
| 1649 | case DW_OP_breg5: |
| 1650 | case DW_OP_breg6: |
| 1651 | case DW_OP_breg7: |
| 1652 | case DW_OP_breg8: |
| 1653 | case DW_OP_breg9: |
| 1654 | case DW_OP_breg10: |
| 1655 | case DW_OP_breg11: |
| 1656 | case DW_OP_breg12: |
| 1657 | case DW_OP_breg13: |
| 1658 | case DW_OP_breg14: |
| 1659 | case DW_OP_breg15: |
| 1660 | case DW_OP_breg16: |
| 1661 | case DW_OP_breg17: |
| 1662 | case DW_OP_breg18: |
| 1663 | case DW_OP_breg19: |
| 1664 | case DW_OP_breg20: |
| 1665 | case DW_OP_breg21: |
| 1666 | case DW_OP_breg22: |
| 1667 | case DW_OP_breg23: |
| 1668 | case DW_OP_breg24: |
| 1669 | case DW_OP_breg25: |
| 1670 | case DW_OP_breg26: |
| 1671 | case DW_OP_breg27: |
| 1672 | case DW_OP_breg28: |
| 1673 | case DW_OP_breg29: |
| 1674 | case DW_OP_breg30: |
| 1675 | case DW_OP_breg31: |
| 1676 | op_ptr = read_sleb128 (op_ptr, op_end, &offset); |
| 1677 | i = translate_register (arch, op - DW_OP_breg0); |
| 1678 | ax_reg (expr, i); |
| 1679 | if (offset != 0) |
| 1680 | { |
| 1681 | ax_const_l (expr, offset); |
| 1682 | ax_simple (expr, aop_add); |
| 1683 | } |
| 1684 | break; |
| 1685 | case DW_OP_bregx: |
| 1686 | { |
| 1687 | op_ptr = read_uleb128 (op_ptr, op_end, ®); |
| 1688 | op_ptr = read_sleb128 (op_ptr, op_end, &offset); |
| 1689 | i = translate_register (arch, reg); |
| 1690 | ax_reg (expr, i); |
| 1691 | if (offset != 0) |
| 1692 | { |
| 1693 | ax_const_l (expr, offset); |
| 1694 | ax_simple (expr, aop_add); |
| 1695 | } |
| 1696 | } |
| 1697 | break; |
| 1698 | case DW_OP_fbreg: |
| 1699 | { |
| 1700 | const gdb_byte *datastart; |
| 1701 | size_t datalen; |
| 1702 | unsigned int before_stack_len; |
| 1703 | struct block *b; |
| 1704 | struct symbol *framefunc; |
| 1705 | LONGEST base_offset = 0; |
| 1706 | |
| 1707 | b = block_for_pc (expr->scope); |
| 1708 | |
| 1709 | if (!b) |
| 1710 | error (_("No block found for address")); |
| 1711 | |
| 1712 | framefunc = block_linkage_function (b); |
| 1713 | |
| 1714 | if (!framefunc) |
| 1715 | error (_("No function found for block")); |
| 1716 | |
| 1717 | dwarf_expr_frame_base_1 (framefunc, expr->scope, |
| 1718 | &datastart, &datalen); |
| 1719 | |
| 1720 | op_ptr = read_sleb128 (op_ptr, op_end, &offset); |
| 1721 | dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, datastart, |
| 1722 | datastart + datalen, per_cu); |
| 1723 | |
| 1724 | if (offset != 0) |
| 1725 | { |
| 1726 | ax_const_l (expr, offset); |
| 1727 | ax_simple (expr, aop_add); |
| 1728 | } |
| 1729 | |
| 1730 | loc->kind = axs_lvalue_memory; |
| 1731 | } |
| 1732 | break; |
| 1733 | |
| 1734 | case DW_OP_dup: |
| 1735 | ax_simple (expr, aop_dup); |
| 1736 | break; |
| 1737 | |
| 1738 | case DW_OP_drop: |
| 1739 | ax_simple (expr, aop_pop); |
| 1740 | break; |
| 1741 | |
| 1742 | case DW_OP_pick: |
| 1743 | offset = *op_ptr++; |
| 1744 | ax_pick (expr, offset); |
| 1745 | break; |
| 1746 | |
| 1747 | case DW_OP_swap: |
| 1748 | ax_simple (expr, aop_swap); |
| 1749 | break; |
| 1750 | |
| 1751 | case DW_OP_over: |
| 1752 | ax_pick (expr, 1); |
| 1753 | break; |
| 1754 | |
| 1755 | case DW_OP_rot: |
| 1756 | ax_simple (expr, aop_rot); |
| 1757 | break; |
| 1758 | |
| 1759 | case DW_OP_deref: |
| 1760 | case DW_OP_deref_size: |
| 1761 | { |
| 1762 | int size; |
| 1763 | |
| 1764 | if (op == DW_OP_deref_size) |
| 1765 | size = *op_ptr++; |
| 1766 | else |
| 1767 | size = addr_size; |
| 1768 | |
| 1769 | switch (size) |
| 1770 | { |
| 1771 | case 8: |
| 1772 | ax_simple (expr, aop_ref8); |
| 1773 | break; |
| 1774 | case 16: |
| 1775 | ax_simple (expr, aop_ref16); |
| 1776 | break; |
| 1777 | case 32: |
| 1778 | ax_simple (expr, aop_ref32); |
| 1779 | break; |
| 1780 | case 64: |
| 1781 | ax_simple (expr, aop_ref64); |
| 1782 | break; |
| 1783 | default: |
| 1784 | /* Note that dwarf_stack_op_name will never return |
| 1785 | NULL here. */ |
| 1786 | error (_("Unsupported size %d in %s"), |
| 1787 | size, dwarf_stack_op_name (op)); |
| 1788 | } |
| 1789 | } |
| 1790 | break; |
| 1791 | |
| 1792 | case DW_OP_abs: |
| 1793 | /* Sign extend the operand. */ |
| 1794 | ax_ext (expr, addr_size_bits); |
| 1795 | ax_simple (expr, aop_dup); |
| 1796 | ax_const_l (expr, 0); |
| 1797 | ax_simple (expr, aop_less_signed); |
| 1798 | ax_simple (expr, aop_log_not); |
| 1799 | i = ax_goto (expr, aop_if_goto); |
| 1800 | /* We have to emit 0 - X. */ |
| 1801 | ax_const_l (expr, 0); |
| 1802 | ax_simple (expr, aop_swap); |
| 1803 | ax_simple (expr, aop_sub); |
| 1804 | ax_label (expr, i, expr->len); |
| 1805 | break; |
| 1806 | |
| 1807 | case DW_OP_neg: |
| 1808 | /* No need to sign extend here. */ |
| 1809 | ax_const_l (expr, 0); |
| 1810 | ax_simple (expr, aop_swap); |
| 1811 | ax_simple (expr, aop_sub); |
| 1812 | break; |
| 1813 | |
| 1814 | case DW_OP_not: |
| 1815 | /* Sign extend the operand. */ |
| 1816 | ax_ext (expr, addr_size_bits); |
| 1817 | ax_simple (expr, aop_bit_not); |
| 1818 | break; |
| 1819 | |
| 1820 | case DW_OP_plus_uconst: |
| 1821 | op_ptr = read_uleb128 (op_ptr, op_end, ®); |
| 1822 | /* It would be really weird to emit `DW_OP_plus_uconst 0', |
| 1823 | but we micro-optimize anyhow. */ |
| 1824 | if (reg != 0) |
| 1825 | { |
| 1826 | ax_const_l (expr, reg); |
| 1827 | ax_simple (expr, aop_add); |
| 1828 | } |
| 1829 | break; |
| 1830 | |
| 1831 | case DW_OP_and: |
| 1832 | ax_simple (expr, aop_bit_and); |
| 1833 | break; |
| 1834 | |
| 1835 | case DW_OP_div: |
| 1836 | /* Sign extend the operands. */ |
| 1837 | ax_ext (expr, addr_size_bits); |
| 1838 | ax_simple (expr, aop_swap); |
| 1839 | ax_ext (expr, addr_size_bits); |
| 1840 | ax_simple (expr, aop_swap); |
| 1841 | ax_simple (expr, aop_div_signed); |
| 1842 | break; |
| 1843 | |
| 1844 | case DW_OP_minus: |
| 1845 | ax_simple (expr, aop_sub); |
| 1846 | break; |
| 1847 | |
| 1848 | case DW_OP_mod: |
| 1849 | ax_simple (expr, aop_rem_unsigned); |
| 1850 | break; |
| 1851 | |
| 1852 | case DW_OP_mul: |
| 1853 | ax_simple (expr, aop_mul); |
| 1854 | break; |
| 1855 | |
| 1856 | case DW_OP_or: |
| 1857 | ax_simple (expr, aop_bit_or); |
| 1858 | break; |
| 1859 | |
| 1860 | case DW_OP_plus: |
| 1861 | ax_simple (expr, aop_add); |
| 1862 | break; |
| 1863 | |
| 1864 | case DW_OP_shl: |
| 1865 | ax_simple (expr, aop_lsh); |
| 1866 | break; |
| 1867 | |
| 1868 | case DW_OP_shr: |
| 1869 | ax_simple (expr, aop_rsh_unsigned); |
| 1870 | break; |
| 1871 | |
| 1872 | case DW_OP_shra: |
| 1873 | ax_simple (expr, aop_rsh_signed); |
| 1874 | break; |
| 1875 | |
| 1876 | case DW_OP_xor: |
| 1877 | ax_simple (expr, aop_bit_xor); |
| 1878 | break; |
| 1879 | |
| 1880 | case DW_OP_le: |
| 1881 | /* Sign extend the operands. */ |
| 1882 | ax_ext (expr, addr_size_bits); |
| 1883 | ax_simple (expr, aop_swap); |
| 1884 | ax_ext (expr, addr_size_bits); |
| 1885 | /* Note no swap here: A <= B is !(B < A). */ |
| 1886 | ax_simple (expr, aop_less_signed); |
| 1887 | ax_simple (expr, aop_log_not); |
| 1888 | break; |
| 1889 | |
| 1890 | case DW_OP_ge: |
| 1891 | /* Sign extend the operands. */ |
| 1892 | ax_ext (expr, addr_size_bits); |
| 1893 | ax_simple (expr, aop_swap); |
| 1894 | ax_ext (expr, addr_size_bits); |
| 1895 | ax_simple (expr, aop_swap); |
| 1896 | /* A >= B is !(A < B). */ |
| 1897 | ax_simple (expr, aop_less_signed); |
| 1898 | ax_simple (expr, aop_log_not); |
| 1899 | break; |
| 1900 | |
| 1901 | case DW_OP_eq: |
| 1902 | /* Sign extend the operands. */ |
| 1903 | ax_ext (expr, addr_size_bits); |
| 1904 | ax_simple (expr, aop_swap); |
| 1905 | ax_ext (expr, addr_size_bits); |
| 1906 | /* No need for a second swap here. */ |
| 1907 | ax_simple (expr, aop_equal); |
| 1908 | break; |
| 1909 | |
| 1910 | case DW_OP_lt: |
| 1911 | /* Sign extend the operands. */ |
| 1912 | ax_ext (expr, addr_size_bits); |
| 1913 | ax_simple (expr, aop_swap); |
| 1914 | ax_ext (expr, addr_size_bits); |
| 1915 | ax_simple (expr, aop_swap); |
| 1916 | ax_simple (expr, aop_less_signed); |
| 1917 | break; |
| 1918 | |
| 1919 | case DW_OP_gt: |
| 1920 | /* Sign extend the operands. */ |
| 1921 | ax_ext (expr, addr_size_bits); |
| 1922 | ax_simple (expr, aop_swap); |
| 1923 | ax_ext (expr, addr_size_bits); |
| 1924 | /* Note no swap here: A > B is B < A. */ |
| 1925 | ax_simple (expr, aop_less_signed); |
| 1926 | break; |
| 1927 | |
| 1928 | case DW_OP_ne: |
| 1929 | /* Sign extend the operands. */ |
| 1930 | ax_ext (expr, addr_size_bits); |
| 1931 | ax_simple (expr, aop_swap); |
| 1932 | ax_ext (expr, addr_size_bits); |
| 1933 | /* No need for a swap here. */ |
| 1934 | ax_simple (expr, aop_equal); |
| 1935 | ax_simple (expr, aop_log_not); |
| 1936 | break; |
| 1937 | |
| 1938 | case DW_OP_call_frame_cfa: |
| 1939 | dwarf2_compile_cfa_to_ax (expr, loc, arch, expr->scope, per_cu); |
| 1940 | loc->kind = axs_lvalue_memory; |
| 1941 | break; |
| 1942 | |
| 1943 | case DW_OP_GNU_push_tls_address: |
| 1944 | unimplemented (op); |
| 1945 | break; |
| 1946 | |
| 1947 | case DW_OP_skip: |
| 1948 | offset = extract_signed_integer (op_ptr, 2, byte_order); |
| 1949 | op_ptr += 2; |
| 1950 | i = ax_goto (expr, aop_goto); |
| 1951 | VEC_safe_push (int, dw_labels, op_ptr + offset - base); |
| 1952 | VEC_safe_push (int, patches, i); |
| 1953 | break; |
| 1954 | |
| 1955 | case DW_OP_bra: |
| 1956 | offset = extract_signed_integer (op_ptr, 2, byte_order); |
| 1957 | op_ptr += 2; |
| 1958 | /* Zero extend the operand. */ |
| 1959 | ax_zero_ext (expr, addr_size_bits); |
| 1960 | i = ax_goto (expr, aop_if_goto); |
| 1961 | VEC_safe_push (int, dw_labels, op_ptr + offset - base); |
| 1962 | VEC_safe_push (int, patches, i); |
| 1963 | break; |
| 1964 | |
| 1965 | case DW_OP_nop: |
| 1966 | break; |
| 1967 | |
| 1968 | case DW_OP_piece: |
| 1969 | case DW_OP_bit_piece: |
| 1970 | { |
| 1971 | ULONGEST size, offset; |
| 1972 | |
| 1973 | if (op_ptr - 1 == previous_piece) |
| 1974 | error (_("Cannot translate empty pieces to agent expressions")); |
| 1975 | previous_piece = op_ptr - 1; |
| 1976 | |
| 1977 | op_ptr = read_uleb128 (op_ptr, op_end, &size); |
| 1978 | if (op == DW_OP_piece) |
| 1979 | { |
| 1980 | size *= 8; |
| 1981 | offset = 0; |
| 1982 | } |
| 1983 | else |
| 1984 | op_ptr = read_uleb128 (op_ptr, op_end, &offset); |
| 1985 | |
| 1986 | if (bits_collected + size > 8 * sizeof (LONGEST)) |
| 1987 | error (_("Expression pieces exceed word size")); |
| 1988 | |
| 1989 | /* Access the bits. */ |
| 1990 | switch (loc->kind) |
| 1991 | { |
| 1992 | case axs_lvalue_register: |
| 1993 | ax_reg (expr, loc->u.reg); |
| 1994 | break; |
| 1995 | |
| 1996 | case axs_lvalue_memory: |
| 1997 | /* Offset the pointer, if needed. */ |
| 1998 | if (offset > 8) |
| 1999 | { |
| 2000 | ax_const_l (expr, offset / 8); |
| 2001 | ax_simple (expr, aop_add); |
| 2002 | offset %= 8; |
| 2003 | } |
| 2004 | access_memory (arch, expr, size); |
| 2005 | break; |
| 2006 | } |
| 2007 | |
| 2008 | /* For a bits-big-endian target, shift up what we already |
| 2009 | have. For a bits-little-endian target, shift up the |
| 2010 | new data. Note that there is a potential bug here if |
| 2011 | the DWARF expression leaves multiple values on the |
| 2012 | stack. */ |
| 2013 | if (bits_collected > 0) |
| 2014 | { |
| 2015 | if (bits_big_endian) |
| 2016 | { |
| 2017 | ax_simple (expr, aop_swap); |
| 2018 | ax_const_l (expr, size); |
| 2019 | ax_simple (expr, aop_lsh); |
| 2020 | /* We don't need a second swap here, because |
| 2021 | aop_bit_or is symmetric. */ |
| 2022 | } |
| 2023 | else |
| 2024 | { |
| 2025 | ax_const_l (expr, size); |
| 2026 | ax_simple (expr, aop_lsh); |
| 2027 | } |
| 2028 | ax_simple (expr, aop_bit_or); |
| 2029 | } |
| 2030 | |
| 2031 | bits_collected += size; |
| 2032 | loc->kind = axs_rvalue; |
| 2033 | } |
| 2034 | break; |
| 2035 | |
| 2036 | case DW_OP_GNU_uninit: |
| 2037 | unimplemented (op); |
| 2038 | |
| 2039 | case DW_OP_call2: |
| 2040 | case DW_OP_call4: |
| 2041 | { |
| 2042 | struct dwarf2_locexpr_baton block; |
| 2043 | int size = (op == DW_OP_call2 ? 2 : 4); |
| 2044 | |
| 2045 | uoffset = extract_unsigned_integer (op_ptr, size, byte_order); |
| 2046 | op_ptr += size; |
| 2047 | |
| 2048 | block = dwarf2_fetch_die_location_block (uoffset, per_cu, |
| 2049 | get_ax_pc, expr); |
| 2050 | |
| 2051 | /* DW_OP_call_ref is currently not supported. */ |
| 2052 | gdb_assert (block.per_cu == per_cu); |
| 2053 | |
| 2054 | dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, |
| 2055 | block.data, block.data + block.size, |
| 2056 | per_cu); |
| 2057 | } |
| 2058 | break; |
| 2059 | |
| 2060 | case DW_OP_call_ref: |
| 2061 | unimplemented (op); |
| 2062 | |
| 2063 | default: |
| 2064 | unimplemented (op); |
| 2065 | } |
| 2066 | } |
| 2067 | |
| 2068 | /* Patch all the branches we emitted. */ |
| 2069 | for (i = 0; i < VEC_length (int, patches); ++i) |
| 2070 | { |
| 2071 | int targ = offsets[VEC_index (int, dw_labels, i)]; |
| 2072 | if (targ == -1) |
| 2073 | internal_error (__FILE__, __LINE__, _("invalid label")); |
| 2074 | ax_label (expr, VEC_index (int, patches, i), targ); |
| 2075 | } |
| 2076 | |
| 2077 | do_cleanups (cleanups); |
| 2078 | } |
| 2079 | |
| 2080 | \f |
| 2081 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression |
| 2082 | evaluator to calculate the location. */ |
| 2083 | static struct value * |
| 2084 | locexpr_read_variable (struct symbol *symbol, struct frame_info *frame) |
| 2085 | { |
| 2086 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2087 | struct value *val; |
| 2088 | |
| 2089 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, dlbaton->data, |
| 2090 | dlbaton->size, dlbaton->per_cu); |
| 2091 | |
| 2092 | return val; |
| 2093 | } |
| 2094 | |
| 2095 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ |
| 2096 | static int |
| 2097 | locexpr_read_needs_frame (struct symbol *symbol) |
| 2098 | { |
| 2099 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2100 | |
| 2101 | return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size, |
| 2102 | dlbaton->per_cu); |
| 2103 | } |
| 2104 | |
| 2105 | /* Return true if DATA points to the end of a piece. END is one past |
| 2106 | the last byte in the expression. */ |
| 2107 | |
| 2108 | static int |
| 2109 | piece_end_p (const gdb_byte *data, const gdb_byte *end) |
| 2110 | { |
| 2111 | return data == end || data[0] == DW_OP_piece || data[0] == DW_OP_bit_piece; |
| 2112 | } |
| 2113 | |
| 2114 | /* Nicely describe a single piece of a location, returning an updated |
| 2115 | position in the bytecode sequence. This function cannot recognize |
| 2116 | all locations; if a location is not recognized, it simply returns |
| 2117 | DATA. */ |
| 2118 | |
| 2119 | static const gdb_byte * |
| 2120 | locexpr_describe_location_piece (struct symbol *symbol, struct ui_file *stream, |
| 2121 | CORE_ADDR addr, struct objfile *objfile, |
| 2122 | const gdb_byte *data, const gdb_byte *end, |
| 2123 | unsigned int addr_size) |
| 2124 | { |
| 2125 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
| 2126 | int regno; |
| 2127 | |
| 2128 | if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31) |
| 2129 | { |
| 2130 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_reg0); |
| 2131 | fprintf_filtered (stream, _("a variable in $%s"), |
| 2132 | gdbarch_register_name (gdbarch, regno)); |
| 2133 | data += 1; |
| 2134 | } |
| 2135 | else if (data[0] == DW_OP_regx) |
| 2136 | { |
| 2137 | ULONGEST reg; |
| 2138 | |
| 2139 | data = read_uleb128 (data + 1, end, ®); |
| 2140 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); |
| 2141 | fprintf_filtered (stream, _("a variable in $%s"), |
| 2142 | gdbarch_register_name (gdbarch, regno)); |
| 2143 | } |
| 2144 | else if (data[0] == DW_OP_fbreg) |
| 2145 | { |
| 2146 | struct block *b; |
| 2147 | struct symbol *framefunc; |
| 2148 | int frame_reg = 0; |
| 2149 | LONGEST frame_offset; |
| 2150 | const gdb_byte *base_data, *new_data, *save_data = data; |
| 2151 | size_t base_size; |
| 2152 | LONGEST base_offset = 0; |
| 2153 | |
| 2154 | new_data = read_sleb128 (data + 1, end, &frame_offset); |
| 2155 | if (!piece_end_p (new_data, end)) |
| 2156 | return data; |
| 2157 | data = new_data; |
| 2158 | |
| 2159 | b = block_for_pc (addr); |
| 2160 | |
| 2161 | if (!b) |
| 2162 | error (_("No block found for address for symbol \"%s\"."), |
| 2163 | SYMBOL_PRINT_NAME (symbol)); |
| 2164 | |
| 2165 | framefunc = block_linkage_function (b); |
| 2166 | |
| 2167 | if (!framefunc) |
| 2168 | error (_("No function found for block for symbol \"%s\"."), |
| 2169 | SYMBOL_PRINT_NAME (symbol)); |
| 2170 | |
| 2171 | dwarf_expr_frame_base_1 (framefunc, addr, &base_data, &base_size); |
| 2172 | |
| 2173 | if (base_data[0] >= DW_OP_breg0 && base_data[0] <= DW_OP_breg31) |
| 2174 | { |
| 2175 | const gdb_byte *buf_end; |
| 2176 | |
| 2177 | frame_reg = base_data[0] - DW_OP_breg0; |
| 2178 | buf_end = read_sleb128 (base_data + 1, |
| 2179 | base_data + base_size, &base_offset); |
| 2180 | if (buf_end != base_data + base_size) |
| 2181 | error (_("Unexpected opcode after " |
| 2182 | "DW_OP_breg%u for symbol \"%s\"."), |
| 2183 | frame_reg, SYMBOL_PRINT_NAME (symbol)); |
| 2184 | } |
| 2185 | else if (base_data[0] >= DW_OP_reg0 && base_data[0] <= DW_OP_reg31) |
| 2186 | { |
| 2187 | /* The frame base is just the register, with no offset. */ |
| 2188 | frame_reg = base_data[0] - DW_OP_reg0; |
| 2189 | base_offset = 0; |
| 2190 | } |
| 2191 | else |
| 2192 | { |
| 2193 | /* We don't know what to do with the frame base expression, |
| 2194 | so we can't trace this variable; give up. */ |
| 2195 | return save_data; |
| 2196 | } |
| 2197 | |
| 2198 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, frame_reg); |
| 2199 | |
| 2200 | fprintf_filtered (stream, |
| 2201 | _("a variable at frame base reg $%s offset %s+%s"), |
| 2202 | gdbarch_register_name (gdbarch, regno), |
| 2203 | plongest (base_offset), plongest (frame_offset)); |
| 2204 | } |
| 2205 | else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31 |
| 2206 | && piece_end_p (data, end)) |
| 2207 | { |
| 2208 | LONGEST offset; |
| 2209 | |
| 2210 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_breg0); |
| 2211 | |
| 2212 | data = read_sleb128 (data + 1, end, &offset); |
| 2213 | |
| 2214 | fprintf_filtered (stream, |
| 2215 | _("a variable at offset %s from base reg $%s"), |
| 2216 | plongest (offset), |
| 2217 | gdbarch_register_name (gdbarch, regno)); |
| 2218 | } |
| 2219 | |
| 2220 | /* The location expression for a TLS variable looks like this (on a |
| 2221 | 64-bit LE machine): |
| 2222 | |
| 2223 | DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0 |
| 2224 | (DW_OP_addr: 4; DW_OP_GNU_push_tls_address) |
| 2225 | |
| 2226 | 0x3 is the encoding for DW_OP_addr, which has an operand as long |
| 2227 | as the size of an address on the target machine (here is 8 |
| 2228 | bytes). Note that more recent version of GCC emit DW_OP_const4u |
| 2229 | or DW_OP_const8u, depending on address size, rather than |
| 2230 | DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address. |
| 2231 | The operand represents the offset at which the variable is within |
| 2232 | the thread local storage. */ |
| 2233 | |
| 2234 | else if (data + 1 + addr_size < end |
| 2235 | && (data[0] == DW_OP_addr |
| 2236 | || (addr_size == 4 && data[0] == DW_OP_const4u) |
| 2237 | || (addr_size == 8 && data[0] == DW_OP_const8u)) |
| 2238 | && data[1 + addr_size] == DW_OP_GNU_push_tls_address |
| 2239 | && piece_end_p (data + 2 + addr_size, end)) |
| 2240 | { |
| 2241 | ULONGEST offset; |
| 2242 | offset = extract_unsigned_integer (data + 1, addr_size, |
| 2243 | gdbarch_byte_order (gdbarch)); |
| 2244 | |
| 2245 | fprintf_filtered (stream, |
| 2246 | _("a thread-local variable at offset 0x%s " |
| 2247 | "in the thread-local storage for `%s'"), |
| 2248 | phex_nz (offset, addr_size), objfile->name); |
| 2249 | |
| 2250 | data += 1 + addr_size + 1; |
| 2251 | } |
| 2252 | else if (data[0] >= DW_OP_lit0 |
| 2253 | && data[0] <= DW_OP_lit31 |
| 2254 | && data + 1 < end |
| 2255 | && data[1] == DW_OP_stack_value) |
| 2256 | { |
| 2257 | fprintf_filtered (stream, _("the constant %d"), data[0] - DW_OP_lit0); |
| 2258 | data += 2; |
| 2259 | } |
| 2260 | |
| 2261 | return data; |
| 2262 | } |
| 2263 | |
| 2264 | /* Disassemble an expression, stopping at the end of a piece or at the |
| 2265 | end of the expression. Returns a pointer to the next unread byte |
| 2266 | in the input expression. If ALL is nonzero, then this function |
| 2267 | will keep going until it reaches the end of the expression. */ |
| 2268 | |
| 2269 | static const gdb_byte * |
| 2270 | disassemble_dwarf_expression (struct ui_file *stream, |
| 2271 | struct gdbarch *arch, unsigned int addr_size, |
| 2272 | int offset_size, |
| 2273 | const gdb_byte *data, const gdb_byte *end, |
| 2274 | int all) |
| 2275 | { |
| 2276 | const gdb_byte *start = data; |
| 2277 | |
| 2278 | fprintf_filtered (stream, _("a complex DWARF expression:\n")); |
| 2279 | |
| 2280 | while (data < end |
| 2281 | && (all |
| 2282 | || (data[0] != DW_OP_piece && data[0] != DW_OP_bit_piece))) |
| 2283 | { |
| 2284 | enum dwarf_location_atom op = *data++; |
| 2285 | ULONGEST ul; |
| 2286 | LONGEST l; |
| 2287 | const char *name; |
| 2288 | |
| 2289 | name = dwarf_stack_op_name (op); |
| 2290 | |
| 2291 | if (!name) |
| 2292 | error (_("Unrecognized DWARF opcode 0x%02x at %ld"), |
| 2293 | op, (long) (data - start)); |
| 2294 | fprintf_filtered (stream, " % 4ld: %s", (long) (data - start), name); |
| 2295 | |
| 2296 | switch (op) |
| 2297 | { |
| 2298 | case DW_OP_addr: |
| 2299 | ul = extract_unsigned_integer (data, addr_size, |
| 2300 | gdbarch_byte_order (arch)); |
| 2301 | data += addr_size; |
| 2302 | fprintf_filtered (stream, " 0x%s", phex_nz (ul, addr_size)); |
| 2303 | break; |
| 2304 | |
| 2305 | case DW_OP_const1u: |
| 2306 | ul = extract_unsigned_integer (data, 1, gdbarch_byte_order (arch)); |
| 2307 | data += 1; |
| 2308 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2309 | break; |
| 2310 | case DW_OP_const1s: |
| 2311 | l = extract_signed_integer (data, 1, gdbarch_byte_order (arch)); |
| 2312 | data += 1; |
| 2313 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2314 | break; |
| 2315 | case DW_OP_const2u: |
| 2316 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); |
| 2317 | data += 2; |
| 2318 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2319 | break; |
| 2320 | case DW_OP_const2s: |
| 2321 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); |
| 2322 | data += 2; |
| 2323 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2324 | break; |
| 2325 | case DW_OP_const4u: |
| 2326 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); |
| 2327 | data += 4; |
| 2328 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2329 | break; |
| 2330 | case DW_OP_const4s: |
| 2331 | l = extract_signed_integer (data, 4, gdbarch_byte_order (arch)); |
| 2332 | data += 4; |
| 2333 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2334 | break; |
| 2335 | case DW_OP_const8u: |
| 2336 | ul = extract_unsigned_integer (data, 8, gdbarch_byte_order (arch)); |
| 2337 | data += 8; |
| 2338 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2339 | break; |
| 2340 | case DW_OP_const8s: |
| 2341 | l = extract_signed_integer (data, 8, gdbarch_byte_order (arch)); |
| 2342 | data += 8; |
| 2343 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2344 | break; |
| 2345 | case DW_OP_constu: |
| 2346 | data = read_uleb128 (data, end, &ul); |
| 2347 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2348 | break; |
| 2349 | case DW_OP_consts: |
| 2350 | data = read_sleb128 (data, end, &l); |
| 2351 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2352 | break; |
| 2353 | |
| 2354 | case DW_OP_reg0: |
| 2355 | case DW_OP_reg1: |
| 2356 | case DW_OP_reg2: |
| 2357 | case DW_OP_reg3: |
| 2358 | case DW_OP_reg4: |
| 2359 | case DW_OP_reg5: |
| 2360 | case DW_OP_reg6: |
| 2361 | case DW_OP_reg7: |
| 2362 | case DW_OP_reg8: |
| 2363 | case DW_OP_reg9: |
| 2364 | case DW_OP_reg10: |
| 2365 | case DW_OP_reg11: |
| 2366 | case DW_OP_reg12: |
| 2367 | case DW_OP_reg13: |
| 2368 | case DW_OP_reg14: |
| 2369 | case DW_OP_reg15: |
| 2370 | case DW_OP_reg16: |
| 2371 | case DW_OP_reg17: |
| 2372 | case DW_OP_reg18: |
| 2373 | case DW_OP_reg19: |
| 2374 | case DW_OP_reg20: |
| 2375 | case DW_OP_reg21: |
| 2376 | case DW_OP_reg22: |
| 2377 | case DW_OP_reg23: |
| 2378 | case DW_OP_reg24: |
| 2379 | case DW_OP_reg25: |
| 2380 | case DW_OP_reg26: |
| 2381 | case DW_OP_reg27: |
| 2382 | case DW_OP_reg28: |
| 2383 | case DW_OP_reg29: |
| 2384 | case DW_OP_reg30: |
| 2385 | case DW_OP_reg31: |
| 2386 | fprintf_filtered (stream, " [$%s]", |
| 2387 | gdbarch_register_name (arch, op - DW_OP_reg0)); |
| 2388 | break; |
| 2389 | |
| 2390 | case DW_OP_regx: |
| 2391 | data = read_uleb128 (data, end, &ul); |
| 2392 | fprintf_filtered (stream, " %s [$%s]", pulongest (ul), |
| 2393 | gdbarch_register_name (arch, (int) ul)); |
| 2394 | break; |
| 2395 | |
| 2396 | case DW_OP_implicit_value: |
| 2397 | data = read_uleb128 (data, end, &ul); |
| 2398 | data += ul; |
| 2399 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2400 | break; |
| 2401 | |
| 2402 | case DW_OP_breg0: |
| 2403 | case DW_OP_breg1: |
| 2404 | case DW_OP_breg2: |
| 2405 | case DW_OP_breg3: |
| 2406 | case DW_OP_breg4: |
| 2407 | case DW_OP_breg5: |
| 2408 | case DW_OP_breg6: |
| 2409 | case DW_OP_breg7: |
| 2410 | case DW_OP_breg8: |
| 2411 | case DW_OP_breg9: |
| 2412 | case DW_OP_breg10: |
| 2413 | case DW_OP_breg11: |
| 2414 | case DW_OP_breg12: |
| 2415 | case DW_OP_breg13: |
| 2416 | case DW_OP_breg14: |
| 2417 | case DW_OP_breg15: |
| 2418 | case DW_OP_breg16: |
| 2419 | case DW_OP_breg17: |
| 2420 | case DW_OP_breg18: |
| 2421 | case DW_OP_breg19: |
| 2422 | case DW_OP_breg20: |
| 2423 | case DW_OP_breg21: |
| 2424 | case DW_OP_breg22: |
| 2425 | case DW_OP_breg23: |
| 2426 | case DW_OP_breg24: |
| 2427 | case DW_OP_breg25: |
| 2428 | case DW_OP_breg26: |
| 2429 | case DW_OP_breg27: |
| 2430 | case DW_OP_breg28: |
| 2431 | case DW_OP_breg29: |
| 2432 | case DW_OP_breg30: |
| 2433 | case DW_OP_breg31: |
| 2434 | data = read_sleb128 (data, end, &l); |
| 2435 | fprintf_filtered (stream, " %s [$%s]", plongest (l), |
| 2436 | gdbarch_register_name (arch, op - DW_OP_breg0)); |
| 2437 | break; |
| 2438 | |
| 2439 | case DW_OP_bregx: |
| 2440 | data = read_uleb128 (data, end, &ul); |
| 2441 | data = read_sleb128 (data, end, &l); |
| 2442 | fprintf_filtered (stream, " register %s [$%s] offset %s", |
| 2443 | pulongest (ul), |
| 2444 | gdbarch_register_name (arch, (int) ul), |
| 2445 | plongest (l)); |
| 2446 | break; |
| 2447 | |
| 2448 | case DW_OP_fbreg: |
| 2449 | data = read_sleb128 (data, end, &l); |
| 2450 | fprintf_filtered (stream, " %s", plongest (l)); |
| 2451 | break; |
| 2452 | |
| 2453 | case DW_OP_xderef_size: |
| 2454 | case DW_OP_deref_size: |
| 2455 | case DW_OP_pick: |
| 2456 | fprintf_filtered (stream, " %d", *data); |
| 2457 | ++data; |
| 2458 | break; |
| 2459 | |
| 2460 | case DW_OP_plus_uconst: |
| 2461 | data = read_uleb128 (data, end, &ul); |
| 2462 | fprintf_filtered (stream, " %s", pulongest (ul)); |
| 2463 | break; |
| 2464 | |
| 2465 | case DW_OP_skip: |
| 2466 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); |
| 2467 | data += 2; |
| 2468 | fprintf_filtered (stream, " to %ld", |
| 2469 | (long) (data + l - start)); |
| 2470 | break; |
| 2471 | |
| 2472 | case DW_OP_bra: |
| 2473 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); |
| 2474 | data += 2; |
| 2475 | fprintf_filtered (stream, " %ld", |
| 2476 | (long) (data + l - start)); |
| 2477 | break; |
| 2478 | |
| 2479 | case DW_OP_call2: |
| 2480 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); |
| 2481 | data += 2; |
| 2482 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 2)); |
| 2483 | break; |
| 2484 | |
| 2485 | case DW_OP_call4: |
| 2486 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); |
| 2487 | data += 4; |
| 2488 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 4)); |
| 2489 | break; |
| 2490 | |
| 2491 | case DW_OP_call_ref: |
| 2492 | ul = extract_unsigned_integer (data, offset_size, |
| 2493 | gdbarch_byte_order (arch)); |
| 2494 | data += offset_size; |
| 2495 | fprintf_filtered (stream, " offset %s", phex_nz (ul, offset_size)); |
| 2496 | break; |
| 2497 | |
| 2498 | case DW_OP_piece: |
| 2499 | data = read_uleb128 (data, end, &ul); |
| 2500 | fprintf_filtered (stream, " %s (bytes)", pulongest (ul)); |
| 2501 | break; |
| 2502 | |
| 2503 | case DW_OP_bit_piece: |
| 2504 | { |
| 2505 | ULONGEST offset; |
| 2506 | |
| 2507 | data = read_uleb128 (data, end, &ul); |
| 2508 | data = read_uleb128 (data, end, &offset); |
| 2509 | fprintf_filtered (stream, " size %s offset %s (bits)", |
| 2510 | pulongest (ul), pulongest (offset)); |
| 2511 | } |
| 2512 | break; |
| 2513 | |
| 2514 | case DW_OP_GNU_implicit_pointer: |
| 2515 | { |
| 2516 | ul = extract_unsigned_integer (data, offset_size, |
| 2517 | gdbarch_byte_order (arch)); |
| 2518 | data += offset_size; |
| 2519 | |
| 2520 | data = read_sleb128 (data, end, &l); |
| 2521 | |
| 2522 | fprintf_filtered (stream, " DIE %s offset %s", |
| 2523 | phex_nz (ul, offset_size), |
| 2524 | plongest (l)); |
| 2525 | } |
| 2526 | break; |
| 2527 | } |
| 2528 | |
| 2529 | fprintf_filtered (stream, "\n"); |
| 2530 | } |
| 2531 | |
| 2532 | return data; |
| 2533 | } |
| 2534 | |
| 2535 | /* Describe a single location, which may in turn consist of multiple |
| 2536 | pieces. */ |
| 2537 | |
| 2538 | static void |
| 2539 | locexpr_describe_location_1 (struct symbol *symbol, CORE_ADDR addr, |
| 2540 | struct ui_file *stream, |
| 2541 | const gdb_byte *data, int size, |
| 2542 | struct objfile *objfile, unsigned int addr_size, |
| 2543 | int offset_size) |
| 2544 | { |
| 2545 | const gdb_byte *end = data + size; |
| 2546 | int first_piece = 1, bad = 0; |
| 2547 | |
| 2548 | while (data < end) |
| 2549 | { |
| 2550 | const gdb_byte *here = data; |
| 2551 | int disassemble = 1; |
| 2552 | |
| 2553 | if (first_piece) |
| 2554 | first_piece = 0; |
| 2555 | else |
| 2556 | fprintf_filtered (stream, _(", and ")); |
| 2557 | |
| 2558 | if (!dwarf2_always_disassemble) |
| 2559 | { |
| 2560 | data = locexpr_describe_location_piece (symbol, stream, |
| 2561 | addr, objfile, |
| 2562 | data, end, addr_size); |
| 2563 | /* If we printed anything, or if we have an empty piece, |
| 2564 | then don't disassemble. */ |
| 2565 | if (data != here |
| 2566 | || data[0] == DW_OP_piece |
| 2567 | || data[0] == DW_OP_bit_piece) |
| 2568 | disassemble = 0; |
| 2569 | } |
| 2570 | if (disassemble) |
| 2571 | data = disassemble_dwarf_expression (stream, |
| 2572 | get_objfile_arch (objfile), |
| 2573 | addr_size, offset_size, data, end, |
| 2574 | dwarf2_always_disassemble); |
| 2575 | |
| 2576 | if (data < end) |
| 2577 | { |
| 2578 | int empty = data == here; |
| 2579 | |
| 2580 | if (disassemble) |
| 2581 | fprintf_filtered (stream, " "); |
| 2582 | if (data[0] == DW_OP_piece) |
| 2583 | { |
| 2584 | ULONGEST bytes; |
| 2585 | |
| 2586 | data = read_uleb128 (data + 1, end, &bytes); |
| 2587 | |
| 2588 | if (empty) |
| 2589 | fprintf_filtered (stream, _("an empty %s-byte piece"), |
| 2590 | pulongest (bytes)); |
| 2591 | else |
| 2592 | fprintf_filtered (stream, _(" [%s-byte piece]"), |
| 2593 | pulongest (bytes)); |
| 2594 | } |
| 2595 | else if (data[0] == DW_OP_bit_piece) |
| 2596 | { |
| 2597 | ULONGEST bits, offset; |
| 2598 | |
| 2599 | data = read_uleb128 (data + 1, end, &bits); |
| 2600 | data = read_uleb128 (data, end, &offset); |
| 2601 | |
| 2602 | if (empty) |
| 2603 | fprintf_filtered (stream, |
| 2604 | _("an empty %s-bit piece"), |
| 2605 | pulongest (bits)); |
| 2606 | else |
| 2607 | fprintf_filtered (stream, |
| 2608 | _(" [%s-bit piece, offset %s bits]"), |
| 2609 | pulongest (bits), pulongest (offset)); |
| 2610 | } |
| 2611 | else |
| 2612 | { |
| 2613 | bad = 1; |
| 2614 | break; |
| 2615 | } |
| 2616 | } |
| 2617 | } |
| 2618 | |
| 2619 | if (bad || data > end) |
| 2620 | error (_("Corrupted DWARF2 expression for \"%s\"."), |
| 2621 | SYMBOL_PRINT_NAME (symbol)); |
| 2622 | } |
| 2623 | |
| 2624 | /* Print a natural-language description of SYMBOL to STREAM. This |
| 2625 | version is for a symbol with a single location. */ |
| 2626 | |
| 2627 | static void |
| 2628 | locexpr_describe_location (struct symbol *symbol, CORE_ADDR addr, |
| 2629 | struct ui_file *stream) |
| 2630 | { |
| 2631 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2632 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); |
| 2633 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
| 2634 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
| 2635 | |
| 2636 | locexpr_describe_location_1 (symbol, addr, stream, |
| 2637 | dlbaton->data, dlbaton->size, |
| 2638 | objfile, addr_size, offset_size); |
| 2639 | } |
| 2640 | |
| 2641 | /* Describe the location of SYMBOL as an agent value in VALUE, generating |
| 2642 | any necessary bytecode in AX. */ |
| 2643 | |
| 2644 | static void |
| 2645 | locexpr_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
| 2646 | struct agent_expr *ax, struct axs_value *value) |
| 2647 | { |
| 2648 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2649 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
| 2650 | |
| 2651 | if (dlbaton->data == NULL || dlbaton->size == 0) |
| 2652 | value->optimized_out = 1; |
| 2653 | else |
| 2654 | dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size, |
| 2655 | dlbaton->data, dlbaton->data + dlbaton->size, |
| 2656 | dlbaton->per_cu); |
| 2657 | } |
| 2658 | |
| 2659 | /* The set of location functions used with the DWARF-2 expression |
| 2660 | evaluator. */ |
| 2661 | const struct symbol_computed_ops dwarf2_locexpr_funcs = { |
| 2662 | locexpr_read_variable, |
| 2663 | locexpr_read_needs_frame, |
| 2664 | locexpr_describe_location, |
| 2665 | locexpr_tracepoint_var_ref |
| 2666 | }; |
| 2667 | |
| 2668 | |
| 2669 | /* Wrapper functions for location lists. These generally find |
| 2670 | the appropriate location expression and call something above. */ |
| 2671 | |
| 2672 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression |
| 2673 | evaluator to calculate the location. */ |
| 2674 | static struct value * |
| 2675 | loclist_read_variable (struct symbol *symbol, struct frame_info *frame) |
| 2676 | { |
| 2677 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2678 | struct value *val; |
| 2679 | const gdb_byte *data; |
| 2680 | size_t size; |
| 2681 | CORE_ADDR pc = frame ? get_frame_address_in_block (frame) : 0; |
| 2682 | |
| 2683 | data = dwarf2_find_location_expression (dlbaton, &size, pc); |
| 2684 | if (data == NULL) |
| 2685 | { |
| 2686 | val = allocate_value (SYMBOL_TYPE (symbol)); |
| 2687 | VALUE_LVAL (val) = not_lval; |
| 2688 | set_value_optimized_out (val, 1); |
| 2689 | } |
| 2690 | else |
| 2691 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, data, size, |
| 2692 | dlbaton->per_cu); |
| 2693 | |
| 2694 | return val; |
| 2695 | } |
| 2696 | |
| 2697 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ |
| 2698 | static int |
| 2699 | loclist_read_needs_frame (struct symbol *symbol) |
| 2700 | { |
| 2701 | /* If there's a location list, then assume we need to have a frame |
| 2702 | to choose the appropriate location expression. With tracking of |
| 2703 | global variables this is not necessarily true, but such tracking |
| 2704 | is disabled in GCC at the moment until we figure out how to |
| 2705 | represent it. */ |
| 2706 | |
| 2707 | return 1; |
| 2708 | } |
| 2709 | |
| 2710 | /* Print a natural-language description of SYMBOL to STREAM. This |
| 2711 | version applies when there is a list of different locations, each |
| 2712 | with a specified address range. */ |
| 2713 | |
| 2714 | static void |
| 2715 | loclist_describe_location (struct symbol *symbol, CORE_ADDR addr, |
| 2716 | struct ui_file *stream) |
| 2717 | { |
| 2718 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2719 | CORE_ADDR low, high; |
| 2720 | const gdb_byte *loc_ptr, *buf_end; |
| 2721 | int length, first = 1; |
| 2722 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); |
| 2723 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
| 2724 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 2725 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
| 2726 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
| 2727 | int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd); |
| 2728 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); |
| 2729 | /* Adjust base_address for relocatable objects. */ |
| 2730 | CORE_ADDR base_offset = dwarf2_per_cu_text_offset (dlbaton->per_cu); |
| 2731 | CORE_ADDR base_address = dlbaton->base_address + base_offset; |
| 2732 | |
| 2733 | loc_ptr = dlbaton->data; |
| 2734 | buf_end = dlbaton->data + dlbaton->size; |
| 2735 | |
| 2736 | fprintf_filtered (stream, _("multi-location:\n")); |
| 2737 | |
| 2738 | /* Iterate through locations until we run out. */ |
| 2739 | while (1) |
| 2740 | { |
| 2741 | if (buf_end - loc_ptr < 2 * addr_size) |
| 2742 | error (_("Corrupted DWARF expression for symbol \"%s\"."), |
| 2743 | SYMBOL_PRINT_NAME (symbol)); |
| 2744 | |
| 2745 | if (signed_addr_p) |
| 2746 | low = extract_signed_integer (loc_ptr, addr_size, byte_order); |
| 2747 | else |
| 2748 | low = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
| 2749 | loc_ptr += addr_size; |
| 2750 | |
| 2751 | if (signed_addr_p) |
| 2752 | high = extract_signed_integer (loc_ptr, addr_size, byte_order); |
| 2753 | else |
| 2754 | high = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
| 2755 | loc_ptr += addr_size; |
| 2756 | |
| 2757 | /* A base-address-selection entry. */ |
| 2758 | if ((low & base_mask) == base_mask) |
| 2759 | { |
| 2760 | base_address = high + base_offset; |
| 2761 | fprintf_filtered (stream, _(" Base address %s"), |
| 2762 | paddress (gdbarch, base_address)); |
| 2763 | continue; |
| 2764 | } |
| 2765 | |
| 2766 | /* An end-of-list entry. */ |
| 2767 | if (low == 0 && high == 0) |
| 2768 | break; |
| 2769 | |
| 2770 | /* Otherwise, a location expression entry. */ |
| 2771 | low += base_address; |
| 2772 | high += base_address; |
| 2773 | |
| 2774 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); |
| 2775 | loc_ptr += 2; |
| 2776 | |
| 2777 | /* (It would improve readability to print only the minimum |
| 2778 | necessary digits of the second number of the range.) */ |
| 2779 | fprintf_filtered (stream, _(" Range %s-%s: "), |
| 2780 | paddress (gdbarch, low), paddress (gdbarch, high)); |
| 2781 | |
| 2782 | /* Now describe this particular location. */ |
| 2783 | locexpr_describe_location_1 (symbol, low, stream, loc_ptr, length, |
| 2784 | objfile, addr_size, offset_size); |
| 2785 | |
| 2786 | fprintf_filtered (stream, "\n"); |
| 2787 | |
| 2788 | loc_ptr += length; |
| 2789 | } |
| 2790 | } |
| 2791 | |
| 2792 | /* Describe the location of SYMBOL as an agent value in VALUE, generating |
| 2793 | any necessary bytecode in AX. */ |
| 2794 | static void |
| 2795 | loclist_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
| 2796 | struct agent_expr *ax, struct axs_value *value) |
| 2797 | { |
| 2798 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
| 2799 | const gdb_byte *data; |
| 2800 | size_t size; |
| 2801 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
| 2802 | |
| 2803 | data = dwarf2_find_location_expression (dlbaton, &size, ax->scope); |
| 2804 | if (data == NULL || size == 0) |
| 2805 | value->optimized_out = 1; |
| 2806 | else |
| 2807 | dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size, data, data + size, |
| 2808 | dlbaton->per_cu); |
| 2809 | } |
| 2810 | |
| 2811 | /* The set of location functions used with the DWARF-2 expression |
| 2812 | evaluator and location lists. */ |
| 2813 | const struct symbol_computed_ops dwarf2_loclist_funcs = { |
| 2814 | loclist_read_variable, |
| 2815 | loclist_read_needs_frame, |
| 2816 | loclist_describe_location, |
| 2817 | loclist_tracepoint_var_ref |
| 2818 | }; |