| 1 | /* Parse expressions for GDB. |
| 2 | |
| 3 | Copyright (C) 1986-2020 Free Software Foundation, Inc. |
| 4 | |
| 5 | Modified from expread.y by the Department of Computer Science at the |
| 6 | State University of New York at Buffalo, 1991. |
| 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 | /* Parse an expression from text in a string, |
| 24 | and return the result as a struct expression pointer. |
| 25 | That structure contains arithmetic operations in reverse polish, |
| 26 | with constants represented by operations that are followed by special data. |
| 27 | See expression.h for the details of the format. |
| 28 | What is important here is that it can be built up sequentially |
| 29 | during the process of parsing; the lower levels of the tree always |
| 30 | come first in the result. */ |
| 31 | |
| 32 | #include "defs.h" |
| 33 | #include <ctype.h> |
| 34 | #include "arch-utils.h" |
| 35 | #include "symtab.h" |
| 36 | #include "gdbtypes.h" |
| 37 | #include "frame.h" |
| 38 | #include "expression.h" |
| 39 | #include "value.h" |
| 40 | #include "command.h" |
| 41 | #include "language.h" |
| 42 | #include "f-lang.h" |
| 43 | #include "parser-defs.h" |
| 44 | #include "gdbcmd.h" |
| 45 | #include "symfile.h" /* for overlay functions */ |
| 46 | #include "inferior.h" |
| 47 | #include "target-float.h" |
| 48 | #include "block.h" |
| 49 | #include "source.h" |
| 50 | #include "objfiles.h" |
| 51 | #include "user-regs.h" |
| 52 | #include <algorithm> |
| 53 | #include "gdbsupport/gdb_optional.h" |
| 54 | |
| 55 | /* Standard set of definitions for printing, dumping, prefixifying, |
| 56 | * and evaluating expressions. */ |
| 57 | |
| 58 | const struct exp_descriptor exp_descriptor_standard = |
| 59 | { |
| 60 | print_subexp_standard, |
| 61 | operator_length_standard, |
| 62 | operator_check_standard, |
| 63 | op_name_standard, |
| 64 | dump_subexp_body_standard, |
| 65 | evaluate_subexp_standard |
| 66 | }; |
| 67 | \f |
| 68 | static unsigned int expressiondebug = 0; |
| 69 | static void |
| 70 | show_expressiondebug (struct ui_file *file, int from_tty, |
| 71 | struct cmd_list_element *c, const char *value) |
| 72 | { |
| 73 | fprintf_filtered (file, _("Expression debugging is %s.\n"), value); |
| 74 | } |
| 75 | |
| 76 | |
| 77 | /* True if an expression parser should set yydebug. */ |
| 78 | bool parser_debug; |
| 79 | |
| 80 | static void |
| 81 | show_parserdebug (struct ui_file *file, int from_tty, |
| 82 | struct cmd_list_element *c, const char *value) |
| 83 | { |
| 84 | fprintf_filtered (file, _("Parser debugging is %s.\n"), value); |
| 85 | } |
| 86 | |
| 87 | |
| 88 | static int prefixify_subexp (struct expression *, struct expression *, int, |
| 89 | int, int); |
| 90 | |
| 91 | static expression_up parse_exp_in_context (const char **, CORE_ADDR, |
| 92 | const struct block *, int, |
| 93 | int, int *, |
| 94 | innermost_block_tracker *, |
| 95 | expr_completion_state *); |
| 96 | |
| 97 | static void increase_expout_size (struct expr_builder *ps, size_t lenelt); |
| 98 | |
| 99 | |
| 100 | /* Documented at it's declaration. */ |
| 101 | |
| 102 | void |
| 103 | innermost_block_tracker::update (const struct block *b, |
| 104 | innermost_block_tracker_types t) |
| 105 | { |
| 106 | if ((m_types & t) != 0 |
| 107 | && (m_innermost_block == NULL |
| 108 | || contained_in (b, m_innermost_block))) |
| 109 | m_innermost_block = b; |
| 110 | } |
| 111 | |
| 112 | \f |
| 113 | |
| 114 | /* See definition in parser-defs.h. */ |
| 115 | |
| 116 | expr_builder::expr_builder (const struct language_defn *lang, |
| 117 | struct gdbarch *gdbarch) |
| 118 | : expout_size (10), |
| 119 | expout (XNEWVAR (expression, |
| 120 | (sizeof (expression) |
| 121 | + EXP_ELEM_TO_BYTES (expout_size)))), |
| 122 | expout_ptr (0) |
| 123 | { |
| 124 | expout->language_defn = lang; |
| 125 | expout->gdbarch = gdbarch; |
| 126 | } |
| 127 | |
| 128 | expression_up |
| 129 | expr_builder::release () |
| 130 | { |
| 131 | /* Record the actual number of expression elements, and then |
| 132 | reallocate the expression memory so that we free up any |
| 133 | excess elements. */ |
| 134 | |
| 135 | expout->nelts = expout_ptr; |
| 136 | expout.reset (XRESIZEVAR (expression, expout.release (), |
| 137 | (sizeof (expression) |
| 138 | + EXP_ELEM_TO_BYTES (expout_ptr)))); |
| 139 | |
| 140 | return std::move (expout); |
| 141 | } |
| 142 | |
| 143 | /* This page contains the functions for adding data to the struct expression |
| 144 | being constructed. */ |
| 145 | |
| 146 | /* Add one element to the end of the expression. */ |
| 147 | |
| 148 | /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into |
| 149 | a register through here. */ |
| 150 | |
| 151 | static void |
| 152 | write_exp_elt (struct expr_builder *ps, const union exp_element *expelt) |
| 153 | { |
| 154 | if (ps->expout_ptr >= ps->expout_size) |
| 155 | { |
| 156 | ps->expout_size *= 2; |
| 157 | ps->expout.reset (XRESIZEVAR (expression, ps->expout.release (), |
| 158 | (sizeof (expression) |
| 159 | + EXP_ELEM_TO_BYTES (ps->expout_size)))); |
| 160 | } |
| 161 | ps->expout->elts[ps->expout_ptr++] = *expelt; |
| 162 | } |
| 163 | |
| 164 | void |
| 165 | write_exp_elt_opcode (struct expr_builder *ps, enum exp_opcode expelt) |
| 166 | { |
| 167 | union exp_element tmp; |
| 168 | |
| 169 | memset (&tmp, 0, sizeof (union exp_element)); |
| 170 | tmp.opcode = expelt; |
| 171 | write_exp_elt (ps, &tmp); |
| 172 | } |
| 173 | |
| 174 | void |
| 175 | write_exp_elt_sym (struct expr_builder *ps, struct symbol *expelt) |
| 176 | { |
| 177 | union exp_element tmp; |
| 178 | |
| 179 | memset (&tmp, 0, sizeof (union exp_element)); |
| 180 | tmp.symbol = expelt; |
| 181 | write_exp_elt (ps, &tmp); |
| 182 | } |
| 183 | |
| 184 | static void |
| 185 | write_exp_elt_msym (struct expr_builder *ps, minimal_symbol *expelt) |
| 186 | { |
| 187 | union exp_element tmp; |
| 188 | |
| 189 | memset (&tmp, 0, sizeof (union exp_element)); |
| 190 | tmp.msymbol = expelt; |
| 191 | write_exp_elt (ps, &tmp); |
| 192 | } |
| 193 | |
| 194 | void |
| 195 | write_exp_elt_block (struct expr_builder *ps, const struct block *b) |
| 196 | { |
| 197 | union exp_element tmp; |
| 198 | |
| 199 | memset (&tmp, 0, sizeof (union exp_element)); |
| 200 | tmp.block = b; |
| 201 | write_exp_elt (ps, &tmp); |
| 202 | } |
| 203 | |
| 204 | void |
| 205 | write_exp_elt_objfile (struct expr_builder *ps, struct objfile *objfile) |
| 206 | { |
| 207 | union exp_element tmp; |
| 208 | |
| 209 | memset (&tmp, 0, sizeof (union exp_element)); |
| 210 | tmp.objfile = objfile; |
| 211 | write_exp_elt (ps, &tmp); |
| 212 | } |
| 213 | |
| 214 | void |
| 215 | write_exp_elt_longcst (struct expr_builder *ps, LONGEST expelt) |
| 216 | { |
| 217 | union exp_element tmp; |
| 218 | |
| 219 | memset (&tmp, 0, sizeof (union exp_element)); |
| 220 | tmp.longconst = expelt; |
| 221 | write_exp_elt (ps, &tmp); |
| 222 | } |
| 223 | |
| 224 | void |
| 225 | write_exp_elt_floatcst (struct expr_builder *ps, const gdb_byte expelt[16]) |
| 226 | { |
| 227 | union exp_element tmp; |
| 228 | int index; |
| 229 | |
| 230 | for (index = 0; index < 16; index++) |
| 231 | tmp.floatconst[index] = expelt[index]; |
| 232 | |
| 233 | write_exp_elt (ps, &tmp); |
| 234 | } |
| 235 | |
| 236 | void |
| 237 | write_exp_elt_type (struct expr_builder *ps, struct type *expelt) |
| 238 | { |
| 239 | union exp_element tmp; |
| 240 | |
| 241 | memset (&tmp, 0, sizeof (union exp_element)); |
| 242 | tmp.type = expelt; |
| 243 | write_exp_elt (ps, &tmp); |
| 244 | } |
| 245 | |
| 246 | void |
| 247 | write_exp_elt_intern (struct expr_builder *ps, struct internalvar *expelt) |
| 248 | { |
| 249 | union exp_element tmp; |
| 250 | |
| 251 | memset (&tmp, 0, sizeof (union exp_element)); |
| 252 | tmp.internalvar = expelt; |
| 253 | write_exp_elt (ps, &tmp); |
| 254 | } |
| 255 | |
| 256 | /* Add a string constant to the end of the expression. |
| 257 | |
| 258 | String constants are stored by first writing an expression element |
| 259 | that contains the length of the string, then stuffing the string |
| 260 | constant itself into however many expression elements are needed |
| 261 | to hold it, and then writing another expression element that contains |
| 262 | the length of the string. I.e. an expression element at each end of |
| 263 | the string records the string length, so you can skip over the |
| 264 | expression elements containing the actual string bytes from either |
| 265 | end of the string. Note that this also allows gdb to handle |
| 266 | strings with embedded null bytes, as is required for some languages. |
| 267 | |
| 268 | Don't be fooled by the fact that the string is null byte terminated, |
| 269 | this is strictly for the convenience of debugging gdb itself. |
| 270 | Gdb does not depend up the string being null terminated, since the |
| 271 | actual length is recorded in expression elements at each end of the |
| 272 | string. The null byte is taken into consideration when computing how |
| 273 | many expression elements are required to hold the string constant, of |
| 274 | course. */ |
| 275 | |
| 276 | |
| 277 | void |
| 278 | write_exp_string (struct expr_builder *ps, struct stoken str) |
| 279 | { |
| 280 | int len = str.length; |
| 281 | size_t lenelt; |
| 282 | char *strdata; |
| 283 | |
| 284 | /* Compute the number of expression elements required to hold the string |
| 285 | (including a null byte terminator), along with one expression element |
| 286 | at each end to record the actual string length (not including the |
| 287 | null byte terminator). */ |
| 288 | |
| 289 | lenelt = 2 + BYTES_TO_EXP_ELEM (len + 1); |
| 290 | |
| 291 | increase_expout_size (ps, lenelt); |
| 292 | |
| 293 | /* Write the leading length expression element (which advances the current |
| 294 | expression element index), then write the string constant followed by a |
| 295 | terminating null byte, and then write the trailing length expression |
| 296 | element. */ |
| 297 | |
| 298 | write_exp_elt_longcst (ps, (LONGEST) len); |
| 299 | strdata = (char *) &ps->expout->elts[ps->expout_ptr]; |
| 300 | memcpy (strdata, str.ptr, len); |
| 301 | *(strdata + len) = '\0'; |
| 302 | ps->expout_ptr += lenelt - 2; |
| 303 | write_exp_elt_longcst (ps, (LONGEST) len); |
| 304 | } |
| 305 | |
| 306 | /* Add a vector of string constants to the end of the expression. |
| 307 | |
| 308 | This adds an OP_STRING operation, but encodes the contents |
| 309 | differently from write_exp_string. The language is expected to |
| 310 | handle evaluation of this expression itself. |
| 311 | |
| 312 | After the usual OP_STRING header, TYPE is written into the |
| 313 | expression as a long constant. The interpretation of this field is |
| 314 | up to the language evaluator. |
| 315 | |
| 316 | Next, each string in VEC is written. The length is written as a |
| 317 | long constant, followed by the contents of the string. */ |
| 318 | |
| 319 | void |
| 320 | write_exp_string_vector (struct expr_builder *ps, int type, |
| 321 | struct stoken_vector *vec) |
| 322 | { |
| 323 | int i, len; |
| 324 | size_t n_slots; |
| 325 | |
| 326 | /* Compute the size. We compute the size in number of slots to |
| 327 | avoid issues with string padding. */ |
| 328 | n_slots = 0; |
| 329 | for (i = 0; i < vec->len; ++i) |
| 330 | { |
| 331 | /* One slot for the length of this element, plus the number of |
| 332 | slots needed for this string. */ |
| 333 | n_slots += 1 + BYTES_TO_EXP_ELEM (vec->tokens[i].length); |
| 334 | } |
| 335 | |
| 336 | /* One more slot for the type of the string. */ |
| 337 | ++n_slots; |
| 338 | |
| 339 | /* Now compute a phony string length. */ |
| 340 | len = EXP_ELEM_TO_BYTES (n_slots) - 1; |
| 341 | |
| 342 | n_slots += 4; |
| 343 | increase_expout_size (ps, n_slots); |
| 344 | |
| 345 | write_exp_elt_opcode (ps, OP_STRING); |
| 346 | write_exp_elt_longcst (ps, len); |
| 347 | write_exp_elt_longcst (ps, type); |
| 348 | |
| 349 | for (i = 0; i < vec->len; ++i) |
| 350 | { |
| 351 | write_exp_elt_longcst (ps, vec->tokens[i].length); |
| 352 | memcpy (&ps->expout->elts[ps->expout_ptr], vec->tokens[i].ptr, |
| 353 | vec->tokens[i].length); |
| 354 | ps->expout_ptr += BYTES_TO_EXP_ELEM (vec->tokens[i].length); |
| 355 | } |
| 356 | |
| 357 | write_exp_elt_longcst (ps, len); |
| 358 | write_exp_elt_opcode (ps, OP_STRING); |
| 359 | } |
| 360 | |
| 361 | /* Add a bitstring constant to the end of the expression. |
| 362 | |
| 363 | Bitstring constants are stored by first writing an expression element |
| 364 | that contains the length of the bitstring (in bits), then stuffing the |
| 365 | bitstring constant itself into however many expression elements are |
| 366 | needed to hold it, and then writing another expression element that |
| 367 | contains the length of the bitstring. I.e. an expression element at |
| 368 | each end of the bitstring records the bitstring length, so you can skip |
| 369 | over the expression elements containing the actual bitstring bytes from |
| 370 | either end of the bitstring. */ |
| 371 | |
| 372 | void |
| 373 | write_exp_bitstring (struct expr_builder *ps, struct stoken str) |
| 374 | { |
| 375 | int bits = str.length; /* length in bits */ |
| 376 | int len = (bits + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT; |
| 377 | size_t lenelt; |
| 378 | char *strdata; |
| 379 | |
| 380 | /* Compute the number of expression elements required to hold the bitstring, |
| 381 | along with one expression element at each end to record the actual |
| 382 | bitstring length in bits. */ |
| 383 | |
| 384 | lenelt = 2 + BYTES_TO_EXP_ELEM (len); |
| 385 | |
| 386 | increase_expout_size (ps, lenelt); |
| 387 | |
| 388 | /* Write the leading length expression element (which advances the current |
| 389 | expression element index), then write the bitstring constant, and then |
| 390 | write the trailing length expression element. */ |
| 391 | |
| 392 | write_exp_elt_longcst (ps, (LONGEST) bits); |
| 393 | strdata = (char *) &ps->expout->elts[ps->expout_ptr]; |
| 394 | memcpy (strdata, str.ptr, len); |
| 395 | ps->expout_ptr += lenelt - 2; |
| 396 | write_exp_elt_longcst (ps, (LONGEST) bits); |
| 397 | } |
| 398 | |
| 399 | /* Return the type of MSYMBOL, a minimal symbol of OBJFILE. If |
| 400 | ADDRESS_P is not NULL, set it to the MSYMBOL's resolved |
| 401 | address. */ |
| 402 | |
| 403 | type * |
| 404 | find_minsym_type_and_address (minimal_symbol *msymbol, |
| 405 | struct objfile *objfile, |
| 406 | CORE_ADDR *address_p) |
| 407 | { |
| 408 | bound_minimal_symbol bound_msym = {msymbol, objfile}; |
| 409 | struct obj_section *section = MSYMBOL_OBJ_SECTION (objfile, msymbol); |
| 410 | enum minimal_symbol_type type = MSYMBOL_TYPE (msymbol); |
| 411 | |
| 412 | bool is_tls = (section != NULL |
| 413 | && section->the_bfd_section->flags & SEC_THREAD_LOCAL); |
| 414 | |
| 415 | /* The minimal symbol might point to a function descriptor; |
| 416 | resolve it to the actual code address instead. */ |
| 417 | CORE_ADDR addr; |
| 418 | if (is_tls) |
| 419 | { |
| 420 | /* Addresses of TLS symbols are really offsets into a |
| 421 | per-objfile/per-thread storage block. */ |
| 422 | addr = MSYMBOL_VALUE_RAW_ADDRESS (bound_msym.minsym); |
| 423 | } |
| 424 | else if (msymbol_is_function (objfile, msymbol, &addr)) |
| 425 | { |
| 426 | if (addr != BMSYMBOL_VALUE_ADDRESS (bound_msym)) |
| 427 | { |
| 428 | /* This means we resolved a function descriptor, and we now |
| 429 | have an address for a code/text symbol instead of a data |
| 430 | symbol. */ |
| 431 | if (MSYMBOL_TYPE (msymbol) == mst_data_gnu_ifunc) |
| 432 | type = mst_text_gnu_ifunc; |
| 433 | else |
| 434 | type = mst_text; |
| 435 | section = NULL; |
| 436 | } |
| 437 | } |
| 438 | else |
| 439 | addr = BMSYMBOL_VALUE_ADDRESS (bound_msym); |
| 440 | |
| 441 | if (overlay_debugging) |
| 442 | addr = symbol_overlayed_address (addr, section); |
| 443 | |
| 444 | if (is_tls) |
| 445 | { |
| 446 | /* Skip translation if caller does not need the address. */ |
| 447 | if (address_p != NULL) |
| 448 | *address_p = target_translate_tls_address (objfile, addr); |
| 449 | return objfile_type (objfile)->nodebug_tls_symbol; |
| 450 | } |
| 451 | |
| 452 | if (address_p != NULL) |
| 453 | *address_p = addr; |
| 454 | |
| 455 | switch (type) |
| 456 | { |
| 457 | case mst_text: |
| 458 | case mst_file_text: |
| 459 | case mst_solib_trampoline: |
| 460 | return objfile_type (objfile)->nodebug_text_symbol; |
| 461 | |
| 462 | case mst_text_gnu_ifunc: |
| 463 | return objfile_type (objfile)->nodebug_text_gnu_ifunc_symbol; |
| 464 | |
| 465 | case mst_data: |
| 466 | case mst_file_data: |
| 467 | case mst_bss: |
| 468 | case mst_file_bss: |
| 469 | return objfile_type (objfile)->nodebug_data_symbol; |
| 470 | |
| 471 | case mst_slot_got_plt: |
| 472 | return objfile_type (objfile)->nodebug_got_plt_symbol; |
| 473 | |
| 474 | default: |
| 475 | return objfile_type (objfile)->nodebug_unknown_symbol; |
| 476 | } |
| 477 | } |
| 478 | |
| 479 | /* Add the appropriate elements for a minimal symbol to the end of |
| 480 | the expression. */ |
| 481 | |
| 482 | void |
| 483 | write_exp_msymbol (struct expr_builder *ps, |
| 484 | struct bound_minimal_symbol bound_msym) |
| 485 | { |
| 486 | write_exp_elt_opcode (ps, OP_VAR_MSYM_VALUE); |
| 487 | write_exp_elt_objfile (ps, bound_msym.objfile); |
| 488 | write_exp_elt_msym (ps, bound_msym.minsym); |
| 489 | write_exp_elt_opcode (ps, OP_VAR_MSYM_VALUE); |
| 490 | } |
| 491 | |
| 492 | /* See parser-defs.h. */ |
| 493 | |
| 494 | void |
| 495 | parser_state::mark_struct_expression () |
| 496 | { |
| 497 | gdb_assert (parse_completion |
| 498 | && (m_completion_state.expout_tag_completion_type |
| 499 | == TYPE_CODE_UNDEF)); |
| 500 | m_completion_state.expout_last_struct = expout_ptr; |
| 501 | } |
| 502 | |
| 503 | /* Indicate that the current parser invocation is completing a tag. |
| 504 | TAG is the type code of the tag, and PTR and LENGTH represent the |
| 505 | start of the tag name. */ |
| 506 | |
| 507 | void |
| 508 | parser_state::mark_completion_tag (enum type_code tag, const char *ptr, |
| 509 | int length) |
| 510 | { |
| 511 | gdb_assert (parse_completion |
| 512 | && (m_completion_state.expout_tag_completion_type |
| 513 | == TYPE_CODE_UNDEF) |
| 514 | && m_completion_state.expout_completion_name == NULL |
| 515 | && m_completion_state.expout_last_struct == -1); |
| 516 | gdb_assert (tag == TYPE_CODE_UNION |
| 517 | || tag == TYPE_CODE_STRUCT |
| 518 | || tag == TYPE_CODE_ENUM); |
| 519 | m_completion_state.expout_tag_completion_type = tag; |
| 520 | m_completion_state.expout_completion_name.reset (xstrndup (ptr, length)); |
| 521 | } |
| 522 | |
| 523 | \f |
| 524 | /* Recognize tokens that start with '$'. These include: |
| 525 | |
| 526 | $regname A native register name or a "standard |
| 527 | register name". |
| 528 | |
| 529 | $variable A convenience variable with a name chosen |
| 530 | by the user. |
| 531 | |
| 532 | $digits Value history with index <digits>, starting |
| 533 | from the first value which has index 1. |
| 534 | |
| 535 | $$digits Value history with index <digits> relative |
| 536 | to the last value. I.e. $$0 is the last |
| 537 | value, $$1 is the one previous to that, $$2 |
| 538 | is the one previous to $$1, etc. |
| 539 | |
| 540 | $ | $0 | $$0 The last value in the value history. |
| 541 | |
| 542 | $$ An abbreviation for the second to the last |
| 543 | value in the value history, I.e. $$1 */ |
| 544 | |
| 545 | void |
| 546 | write_dollar_variable (struct parser_state *ps, struct stoken str) |
| 547 | { |
| 548 | struct block_symbol sym; |
| 549 | struct bound_minimal_symbol msym; |
| 550 | struct internalvar *isym = NULL; |
| 551 | std::string copy; |
| 552 | |
| 553 | /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1) |
| 554 | and $$digits (equivalent to $<-digits> if you could type that). */ |
| 555 | |
| 556 | int negate = 0; |
| 557 | int i = 1; |
| 558 | /* Double dollar means negate the number and add -1 as well. |
| 559 | Thus $$ alone means -1. */ |
| 560 | if (str.length >= 2 && str.ptr[1] == '$') |
| 561 | { |
| 562 | negate = 1; |
| 563 | i = 2; |
| 564 | } |
| 565 | if (i == str.length) |
| 566 | { |
| 567 | /* Just dollars (one or two). */ |
| 568 | i = -negate; |
| 569 | goto handle_last; |
| 570 | } |
| 571 | /* Is the rest of the token digits? */ |
| 572 | for (; i < str.length; i++) |
| 573 | if (!(str.ptr[i] >= '0' && str.ptr[i] <= '9')) |
| 574 | break; |
| 575 | if (i == str.length) |
| 576 | { |
| 577 | i = atoi (str.ptr + 1 + negate); |
| 578 | if (negate) |
| 579 | i = -i; |
| 580 | goto handle_last; |
| 581 | } |
| 582 | |
| 583 | /* Handle tokens that refer to machine registers: |
| 584 | $ followed by a register name. */ |
| 585 | i = user_reg_map_name_to_regnum (ps->gdbarch (), |
| 586 | str.ptr + 1, str.length - 1); |
| 587 | if (i >= 0) |
| 588 | goto handle_register; |
| 589 | |
| 590 | /* Any names starting with $ are probably debugger internal variables. */ |
| 591 | |
| 592 | copy = copy_name (str); |
| 593 | isym = lookup_only_internalvar (copy.c_str () + 1); |
| 594 | if (isym) |
| 595 | { |
| 596 | write_exp_elt_opcode (ps, OP_INTERNALVAR); |
| 597 | write_exp_elt_intern (ps, isym); |
| 598 | write_exp_elt_opcode (ps, OP_INTERNALVAR); |
| 599 | return; |
| 600 | } |
| 601 | |
| 602 | /* On some systems, such as HP-UX and hppa-linux, certain system routines |
| 603 | have names beginning with $ or $$. Check for those, first. */ |
| 604 | |
| 605 | sym = lookup_symbol (copy.c_str (), NULL, VAR_DOMAIN, NULL); |
| 606 | if (sym.symbol) |
| 607 | { |
| 608 | write_exp_elt_opcode (ps, OP_VAR_VALUE); |
| 609 | write_exp_elt_block (ps, sym.block); |
| 610 | write_exp_elt_sym (ps, sym.symbol); |
| 611 | write_exp_elt_opcode (ps, OP_VAR_VALUE); |
| 612 | return; |
| 613 | } |
| 614 | msym = lookup_bound_minimal_symbol (copy.c_str ()); |
| 615 | if (msym.minsym) |
| 616 | { |
| 617 | write_exp_msymbol (ps, msym); |
| 618 | return; |
| 619 | } |
| 620 | |
| 621 | /* Any other names are assumed to be debugger internal variables. */ |
| 622 | |
| 623 | write_exp_elt_opcode (ps, OP_INTERNALVAR); |
| 624 | write_exp_elt_intern (ps, create_internalvar (copy.c_str () + 1)); |
| 625 | write_exp_elt_opcode (ps, OP_INTERNALVAR); |
| 626 | return; |
| 627 | handle_last: |
| 628 | write_exp_elt_opcode (ps, OP_LAST); |
| 629 | write_exp_elt_longcst (ps, (LONGEST) i); |
| 630 | write_exp_elt_opcode (ps, OP_LAST); |
| 631 | return; |
| 632 | handle_register: |
| 633 | write_exp_elt_opcode (ps, OP_REGISTER); |
| 634 | str.length--; |
| 635 | str.ptr++; |
| 636 | write_exp_string (ps, str); |
| 637 | write_exp_elt_opcode (ps, OP_REGISTER); |
| 638 | ps->block_tracker->update (ps->expression_context_block, |
| 639 | INNERMOST_BLOCK_FOR_REGISTERS); |
| 640 | return; |
| 641 | } |
| 642 | |
| 643 | |
| 644 | const char * |
| 645 | find_template_name_end (const char *p) |
| 646 | { |
| 647 | int depth = 1; |
| 648 | int just_seen_right = 0; |
| 649 | int just_seen_colon = 0; |
| 650 | int just_seen_space = 0; |
| 651 | |
| 652 | if (!p || (*p != '<')) |
| 653 | return 0; |
| 654 | |
| 655 | while (*++p) |
| 656 | { |
| 657 | switch (*p) |
| 658 | { |
| 659 | case '\'': |
| 660 | case '\"': |
| 661 | case '{': |
| 662 | case '}': |
| 663 | /* In future, may want to allow these?? */ |
| 664 | return 0; |
| 665 | case '<': |
| 666 | depth++; /* start nested template */ |
| 667 | if (just_seen_colon || just_seen_right || just_seen_space) |
| 668 | return 0; /* but not after : or :: or > or space */ |
| 669 | break; |
| 670 | case '>': |
| 671 | if (just_seen_colon || just_seen_right) |
| 672 | return 0; /* end a (nested?) template */ |
| 673 | just_seen_right = 1; /* but not after : or :: */ |
| 674 | if (--depth == 0) /* also disallow >>, insist on > > */ |
| 675 | return ++p; /* if outermost ended, return */ |
| 676 | break; |
| 677 | case ':': |
| 678 | if (just_seen_space || (just_seen_colon > 1)) |
| 679 | return 0; /* nested class spec coming up */ |
| 680 | just_seen_colon++; /* we allow :: but not :::: */ |
| 681 | break; |
| 682 | case ' ': |
| 683 | break; |
| 684 | default: |
| 685 | if (!((*p >= 'a' && *p <= 'z') || /* allow token chars */ |
| 686 | (*p >= 'A' && *p <= 'Z') || |
| 687 | (*p >= '0' && *p <= '9') || |
| 688 | (*p == '_') || (*p == ',') || /* commas for template args */ |
| 689 | (*p == '&') || (*p == '*') || /* pointer and ref types */ |
| 690 | (*p == '(') || (*p == ')') || /* function types */ |
| 691 | (*p == '[') || (*p == ']'))) /* array types */ |
| 692 | return 0; |
| 693 | } |
| 694 | if (*p != ' ') |
| 695 | just_seen_space = 0; |
| 696 | if (*p != ':') |
| 697 | just_seen_colon = 0; |
| 698 | if (*p != '>') |
| 699 | just_seen_right = 0; |
| 700 | } |
| 701 | return 0; |
| 702 | } |
| 703 | \f |
| 704 | |
| 705 | /* Return a null-terminated temporary copy of the name of a string token. |
| 706 | |
| 707 | Tokens that refer to names do so with explicit pointer and length, |
| 708 | so they can share the storage that lexptr is parsing. |
| 709 | When it is necessary to pass a name to a function that expects |
| 710 | a null-terminated string, the substring is copied out |
| 711 | into a separate block of storage. */ |
| 712 | |
| 713 | std::string |
| 714 | copy_name (struct stoken token) |
| 715 | { |
| 716 | return std::string (token.ptr, token.length); |
| 717 | } |
| 718 | \f |
| 719 | |
| 720 | /* See comments on parser-defs.h. */ |
| 721 | |
| 722 | int |
| 723 | prefixify_expression (struct expression *expr, int last_struct) |
| 724 | { |
| 725 | gdb_assert (expr->nelts > 0); |
| 726 | int len = sizeof (struct expression) + EXP_ELEM_TO_BYTES (expr->nelts); |
| 727 | struct expression *temp; |
| 728 | int inpos = expr->nelts, outpos = 0; |
| 729 | |
| 730 | temp = (struct expression *) alloca (len); |
| 731 | |
| 732 | /* Copy the original expression into temp. */ |
| 733 | memcpy (temp, expr, len); |
| 734 | |
| 735 | return prefixify_subexp (temp, expr, inpos, outpos, last_struct); |
| 736 | } |
| 737 | |
| 738 | /* Return the number of exp_elements in the postfix subexpression |
| 739 | of EXPR whose operator is at index ENDPOS - 1 in EXPR. */ |
| 740 | |
| 741 | static int |
| 742 | length_of_subexp (struct expression *expr, int endpos) |
| 743 | { |
| 744 | int oplen, args; |
| 745 | |
| 746 | operator_length (expr, endpos, &oplen, &args); |
| 747 | |
| 748 | while (args > 0) |
| 749 | { |
| 750 | oplen += length_of_subexp (expr, endpos - oplen); |
| 751 | args--; |
| 752 | } |
| 753 | |
| 754 | return oplen; |
| 755 | } |
| 756 | |
| 757 | /* Sets *OPLENP to the length of the operator whose (last) index is |
| 758 | ENDPOS - 1 in EXPR, and sets *ARGSP to the number of arguments that |
| 759 | operator takes. */ |
| 760 | |
| 761 | void |
| 762 | operator_length (const struct expression *expr, int endpos, int *oplenp, |
| 763 | int *argsp) |
| 764 | { |
| 765 | expr->language_defn->la_exp_desc->operator_length (expr, endpos, |
| 766 | oplenp, argsp); |
| 767 | } |
| 768 | |
| 769 | /* Default value for operator_length in exp_descriptor vectors. */ |
| 770 | |
| 771 | void |
| 772 | operator_length_standard (const struct expression *expr, int endpos, |
| 773 | int *oplenp, int *argsp) |
| 774 | { |
| 775 | int oplen = 1; |
| 776 | int args = 0; |
| 777 | enum range_type range_type; |
| 778 | int i; |
| 779 | |
| 780 | if (endpos < 1) |
| 781 | error (_("?error in operator_length_standard")); |
| 782 | |
| 783 | i = (int) expr->elts[endpos - 1].opcode; |
| 784 | |
| 785 | switch (i) |
| 786 | { |
| 787 | /* C++ */ |
| 788 | case OP_SCOPE: |
| 789 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 790 | oplen = 5 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 791 | break; |
| 792 | |
| 793 | case OP_LONG: |
| 794 | case OP_FLOAT: |
| 795 | case OP_VAR_VALUE: |
| 796 | case OP_VAR_MSYM_VALUE: |
| 797 | oplen = 4; |
| 798 | break; |
| 799 | |
| 800 | case OP_FUNC_STATIC_VAR: |
| 801 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 802 | oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 803 | args = 1; |
| 804 | break; |
| 805 | |
| 806 | case OP_TYPE: |
| 807 | case OP_BOOL: |
| 808 | case OP_LAST: |
| 809 | case OP_INTERNALVAR: |
| 810 | case OP_VAR_ENTRY_VALUE: |
| 811 | oplen = 3; |
| 812 | break; |
| 813 | |
| 814 | case OP_COMPLEX: |
| 815 | oplen = 3; |
| 816 | args = 2; |
| 817 | break; |
| 818 | |
| 819 | case OP_FUNCALL: |
| 820 | case OP_F77_UNDETERMINED_ARGLIST: |
| 821 | oplen = 3; |
| 822 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 823 | break; |
| 824 | |
| 825 | case TYPE_INSTANCE: |
| 826 | oplen = 5 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 827 | args = 1; |
| 828 | break; |
| 829 | |
| 830 | case OP_OBJC_MSGCALL: /* Objective C message (method) call. */ |
| 831 | oplen = 4; |
| 832 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 833 | break; |
| 834 | |
| 835 | case UNOP_MAX: |
| 836 | case UNOP_MIN: |
| 837 | oplen = 3; |
| 838 | break; |
| 839 | |
| 840 | case UNOP_CAST_TYPE: |
| 841 | case UNOP_DYNAMIC_CAST: |
| 842 | case UNOP_REINTERPRET_CAST: |
| 843 | case UNOP_MEMVAL_TYPE: |
| 844 | oplen = 1; |
| 845 | args = 2; |
| 846 | break; |
| 847 | |
| 848 | case BINOP_VAL: |
| 849 | case UNOP_CAST: |
| 850 | case UNOP_MEMVAL: |
| 851 | oplen = 3; |
| 852 | args = 1; |
| 853 | break; |
| 854 | |
| 855 | case UNOP_ABS: |
| 856 | case UNOP_CAP: |
| 857 | case UNOP_CHR: |
| 858 | case UNOP_FLOAT: |
| 859 | case UNOP_HIGH: |
| 860 | case UNOP_ODD: |
| 861 | case UNOP_ORD: |
| 862 | case UNOP_TRUNC: |
| 863 | case OP_TYPEOF: |
| 864 | case OP_DECLTYPE: |
| 865 | case OP_TYPEID: |
| 866 | oplen = 1; |
| 867 | args = 1; |
| 868 | break; |
| 869 | |
| 870 | case OP_ADL_FUNC: |
| 871 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 872 | oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 873 | oplen++; |
| 874 | oplen++; |
| 875 | break; |
| 876 | |
| 877 | case STRUCTOP_STRUCT: |
| 878 | case STRUCTOP_PTR: |
| 879 | args = 1; |
| 880 | /* fall through */ |
| 881 | case OP_REGISTER: |
| 882 | case OP_M2_STRING: |
| 883 | case OP_STRING: |
| 884 | case OP_OBJC_NSSTRING: /* Objective C Foundation Class |
| 885 | NSString constant. */ |
| 886 | case OP_OBJC_SELECTOR: /* Objective C "@selector" pseudo-op. */ |
| 887 | case OP_NAME: |
| 888 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 889 | oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 890 | break; |
| 891 | |
| 892 | case OP_ARRAY: |
| 893 | oplen = 4; |
| 894 | args = longest_to_int (expr->elts[endpos - 2].longconst); |
| 895 | args -= longest_to_int (expr->elts[endpos - 3].longconst); |
| 896 | args += 1; |
| 897 | break; |
| 898 | |
| 899 | case TERNOP_COND: |
| 900 | case TERNOP_SLICE: |
| 901 | args = 3; |
| 902 | break; |
| 903 | |
| 904 | /* Modula-2 */ |
| 905 | case MULTI_SUBSCRIPT: |
| 906 | oplen = 3; |
| 907 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 908 | break; |
| 909 | |
| 910 | case BINOP_ASSIGN_MODIFY: |
| 911 | oplen = 3; |
| 912 | args = 2; |
| 913 | break; |
| 914 | |
| 915 | /* C++ */ |
| 916 | case OP_THIS: |
| 917 | oplen = 2; |
| 918 | break; |
| 919 | |
| 920 | case OP_RANGE: |
| 921 | oplen = 3; |
| 922 | range_type = (enum range_type) |
| 923 | longest_to_int (expr->elts[endpos - 2].longconst); |
| 924 | |
| 925 | switch (range_type) |
| 926 | { |
| 927 | case LOW_BOUND_DEFAULT: |
| 928 | case LOW_BOUND_DEFAULT_EXCLUSIVE: |
| 929 | case HIGH_BOUND_DEFAULT: |
| 930 | args = 1; |
| 931 | break; |
| 932 | case BOTH_BOUND_DEFAULT: |
| 933 | args = 0; |
| 934 | break; |
| 935 | case NONE_BOUND_DEFAULT: |
| 936 | case NONE_BOUND_DEFAULT_EXCLUSIVE: |
| 937 | args = 2; |
| 938 | break; |
| 939 | } |
| 940 | |
| 941 | break; |
| 942 | |
| 943 | default: |
| 944 | args = 1 + (i < (int) BINOP_END); |
| 945 | } |
| 946 | |
| 947 | *oplenp = oplen; |
| 948 | *argsp = args; |
| 949 | } |
| 950 | |
| 951 | /* Copy the subexpression ending just before index INEND in INEXPR |
| 952 | into OUTEXPR, starting at index OUTBEG. |
| 953 | In the process, convert it from suffix to prefix form. |
| 954 | If LAST_STRUCT is -1, then this function always returns -1. |
| 955 | Otherwise, it returns the index of the subexpression which is the |
| 956 | left-hand-side of the expression at LAST_STRUCT. */ |
| 957 | |
| 958 | static int |
| 959 | prefixify_subexp (struct expression *inexpr, |
| 960 | struct expression *outexpr, int inend, int outbeg, |
| 961 | int last_struct) |
| 962 | { |
| 963 | int oplen; |
| 964 | int args; |
| 965 | int i; |
| 966 | int *arglens; |
| 967 | int result = -1; |
| 968 | |
| 969 | operator_length (inexpr, inend, &oplen, &args); |
| 970 | |
| 971 | /* Copy the final operator itself, from the end of the input |
| 972 | to the beginning of the output. */ |
| 973 | inend -= oplen; |
| 974 | memcpy (&outexpr->elts[outbeg], &inexpr->elts[inend], |
| 975 | EXP_ELEM_TO_BYTES (oplen)); |
| 976 | outbeg += oplen; |
| 977 | |
| 978 | if (last_struct == inend) |
| 979 | result = outbeg - oplen; |
| 980 | |
| 981 | /* Find the lengths of the arg subexpressions. */ |
| 982 | arglens = (int *) alloca (args * sizeof (int)); |
| 983 | for (i = args - 1; i >= 0; i--) |
| 984 | { |
| 985 | oplen = length_of_subexp (inexpr, inend); |
| 986 | arglens[i] = oplen; |
| 987 | inend -= oplen; |
| 988 | } |
| 989 | |
| 990 | /* Now copy each subexpression, preserving the order of |
| 991 | the subexpressions, but prefixifying each one. |
| 992 | In this loop, inend starts at the beginning of |
| 993 | the expression this level is working on |
| 994 | and marches forward over the arguments. |
| 995 | outbeg does similarly in the output. */ |
| 996 | for (i = 0; i < args; i++) |
| 997 | { |
| 998 | int r; |
| 999 | |
| 1000 | oplen = arglens[i]; |
| 1001 | inend += oplen; |
| 1002 | r = prefixify_subexp (inexpr, outexpr, inend, outbeg, last_struct); |
| 1003 | if (r != -1) |
| 1004 | { |
| 1005 | /* Return immediately. We probably have only parsed a |
| 1006 | partial expression, so we don't want to try to reverse |
| 1007 | the other operands. */ |
| 1008 | return r; |
| 1009 | } |
| 1010 | outbeg += oplen; |
| 1011 | } |
| 1012 | |
| 1013 | return result; |
| 1014 | } |
| 1015 | \f |
| 1016 | /* Read an expression from the string *STRINGPTR points to, |
| 1017 | parse it, and return a pointer to a struct expression that we malloc. |
| 1018 | Use block BLOCK as the lexical context for variable names; |
| 1019 | if BLOCK is zero, use the block of the selected stack frame. |
| 1020 | Meanwhile, advance *STRINGPTR to point after the expression, |
| 1021 | at the first nonwhite character that is not part of the expression |
| 1022 | (possibly a null character). |
| 1023 | |
| 1024 | If COMMA is nonzero, stop if a comma is reached. */ |
| 1025 | |
| 1026 | expression_up |
| 1027 | parse_exp_1 (const char **stringptr, CORE_ADDR pc, const struct block *block, |
| 1028 | int comma, innermost_block_tracker *tracker) |
| 1029 | { |
| 1030 | return parse_exp_in_context (stringptr, pc, block, comma, 0, NULL, |
| 1031 | tracker, nullptr); |
| 1032 | } |
| 1033 | |
| 1034 | /* As for parse_exp_1, except that if VOID_CONTEXT_P, then |
| 1035 | no value is expected from the expression. |
| 1036 | OUT_SUBEXP is set when attempting to complete a field name; in this |
| 1037 | case it is set to the index of the subexpression on the |
| 1038 | left-hand-side of the struct op. If not doing such completion, it |
| 1039 | is left untouched. */ |
| 1040 | |
| 1041 | static expression_up |
| 1042 | parse_exp_in_context (const char **stringptr, CORE_ADDR pc, |
| 1043 | const struct block *block, |
| 1044 | int comma, int void_context_p, int *out_subexp, |
| 1045 | innermost_block_tracker *tracker, |
| 1046 | expr_completion_state *cstate) |
| 1047 | { |
| 1048 | const struct language_defn *lang = NULL; |
| 1049 | int subexp; |
| 1050 | |
| 1051 | if (*stringptr == 0 || **stringptr == 0) |
| 1052 | error_no_arg (_("expression to compute")); |
| 1053 | |
| 1054 | const struct block *expression_context_block = block; |
| 1055 | CORE_ADDR expression_context_pc = 0; |
| 1056 | |
| 1057 | innermost_block_tracker local_tracker; |
| 1058 | if (tracker == nullptr) |
| 1059 | tracker = &local_tracker; |
| 1060 | |
| 1061 | /* If no context specified, try using the current frame, if any. */ |
| 1062 | if (!expression_context_block) |
| 1063 | expression_context_block = get_selected_block (&expression_context_pc); |
| 1064 | else if (pc == 0) |
| 1065 | expression_context_pc = BLOCK_ENTRY_PC (expression_context_block); |
| 1066 | else |
| 1067 | expression_context_pc = pc; |
| 1068 | |
| 1069 | /* Fall back to using the current source static context, if any. */ |
| 1070 | |
| 1071 | if (!expression_context_block) |
| 1072 | { |
| 1073 | struct symtab_and_line cursal = get_current_source_symtab_and_line (); |
| 1074 | if (cursal.symtab) |
| 1075 | expression_context_block |
| 1076 | = BLOCKVECTOR_BLOCK (SYMTAB_BLOCKVECTOR (cursal.symtab), |
| 1077 | STATIC_BLOCK); |
| 1078 | if (expression_context_block) |
| 1079 | expression_context_pc = BLOCK_ENTRY_PC (expression_context_block); |
| 1080 | } |
| 1081 | |
| 1082 | if (language_mode == language_mode_auto && block != NULL) |
| 1083 | { |
| 1084 | /* Find the language associated to the given context block. |
| 1085 | Default to the current language if it can not be determined. |
| 1086 | |
| 1087 | Note that using the language corresponding to the current frame |
| 1088 | can sometimes give unexpected results. For instance, this |
| 1089 | routine is often called several times during the inferior |
| 1090 | startup phase to re-parse breakpoint expressions after |
| 1091 | a new shared library has been loaded. The language associated |
| 1092 | to the current frame at this moment is not relevant for |
| 1093 | the breakpoint. Using it would therefore be silly, so it seems |
| 1094 | better to rely on the current language rather than relying on |
| 1095 | the current frame language to parse the expression. That's why |
| 1096 | we do the following language detection only if the context block |
| 1097 | has been specifically provided. */ |
| 1098 | struct symbol *func = block_linkage_function (block); |
| 1099 | |
| 1100 | if (func != NULL) |
| 1101 | lang = language_def (func->language ()); |
| 1102 | if (lang == NULL || lang->la_language == language_unknown) |
| 1103 | lang = current_language; |
| 1104 | } |
| 1105 | else |
| 1106 | lang = current_language; |
| 1107 | |
| 1108 | /* get_current_arch may reset CURRENT_LANGUAGE via select_frame. |
| 1109 | While we need CURRENT_LANGUAGE to be set to LANG (for lookup_symbol |
| 1110 | and others called from *.y) ensure CURRENT_LANGUAGE gets restored |
| 1111 | to the value matching SELECTED_FRAME as set by get_current_arch. */ |
| 1112 | |
| 1113 | parser_state ps (lang, get_current_arch (), expression_context_block, |
| 1114 | expression_context_pc, comma, *stringptr, |
| 1115 | cstate != nullptr, tracker); |
| 1116 | |
| 1117 | scoped_restore_current_language lang_saver; |
| 1118 | set_language (lang->la_language); |
| 1119 | |
| 1120 | try |
| 1121 | { |
| 1122 | lang->la_parser (&ps); |
| 1123 | } |
| 1124 | catch (const gdb_exception &except) |
| 1125 | { |
| 1126 | /* If parsing for completion, allow this to succeed; but if no |
| 1127 | expression elements have been written, then there's nothing |
| 1128 | to do, so fail. */ |
| 1129 | if (! ps.parse_completion || ps.expout_ptr == 0) |
| 1130 | throw; |
| 1131 | } |
| 1132 | |
| 1133 | /* We have to operate on an "expression *", due to la_post_parser, |
| 1134 | which explains this funny-looking double release. */ |
| 1135 | expression_up result = ps.release (); |
| 1136 | |
| 1137 | /* Convert expression from postfix form as generated by yacc |
| 1138 | parser, to a prefix form. */ |
| 1139 | |
| 1140 | if (expressiondebug) |
| 1141 | dump_raw_expression (result.get (), gdb_stdlog, |
| 1142 | "before conversion to prefix form"); |
| 1143 | |
| 1144 | subexp = prefixify_expression (result.get (), |
| 1145 | ps.m_completion_state.expout_last_struct); |
| 1146 | if (out_subexp) |
| 1147 | *out_subexp = subexp; |
| 1148 | |
| 1149 | lang->la_post_parser (&result, void_context_p, ps.parse_completion, |
| 1150 | tracker); |
| 1151 | |
| 1152 | if (expressiondebug) |
| 1153 | dump_prefix_expression (result.get (), gdb_stdlog); |
| 1154 | |
| 1155 | if (cstate != nullptr) |
| 1156 | *cstate = std::move (ps.m_completion_state); |
| 1157 | *stringptr = ps.lexptr; |
| 1158 | return result; |
| 1159 | } |
| 1160 | |
| 1161 | /* Parse STRING as an expression, and complain if this fails |
| 1162 | to use up all of the contents of STRING. */ |
| 1163 | |
| 1164 | expression_up |
| 1165 | parse_expression (const char *string, innermost_block_tracker *tracker) |
| 1166 | { |
| 1167 | expression_up exp = parse_exp_1 (&string, 0, 0, 0, tracker); |
| 1168 | if (*string) |
| 1169 | error (_("Junk after end of expression.")); |
| 1170 | return exp; |
| 1171 | } |
| 1172 | |
| 1173 | /* Same as parse_expression, but using the given language (LANG) |
| 1174 | to parse the expression. */ |
| 1175 | |
| 1176 | expression_up |
| 1177 | parse_expression_with_language (const char *string, enum language lang) |
| 1178 | { |
| 1179 | gdb::optional<scoped_restore_current_language> lang_saver; |
| 1180 | if (current_language->la_language != lang) |
| 1181 | { |
| 1182 | lang_saver.emplace (); |
| 1183 | set_language (lang); |
| 1184 | } |
| 1185 | |
| 1186 | return parse_expression (string); |
| 1187 | } |
| 1188 | |
| 1189 | /* Parse STRING as an expression. If parsing ends in the middle of a |
| 1190 | field reference, return the type of the left-hand-side of the |
| 1191 | reference; furthermore, if the parsing ends in the field name, |
| 1192 | return the field name in *NAME. If the parsing ends in the middle |
| 1193 | of a field reference, but the reference is somehow invalid, throw |
| 1194 | an exception. In all other cases, return NULL. */ |
| 1195 | |
| 1196 | struct type * |
| 1197 | parse_expression_for_completion (const char *string, |
| 1198 | gdb::unique_xmalloc_ptr<char> *name, |
| 1199 | enum type_code *code) |
| 1200 | { |
| 1201 | expression_up exp; |
| 1202 | struct value *val; |
| 1203 | int subexp; |
| 1204 | expr_completion_state cstate; |
| 1205 | |
| 1206 | try |
| 1207 | { |
| 1208 | exp = parse_exp_in_context (&string, 0, 0, 0, 0, &subexp, |
| 1209 | nullptr, &cstate); |
| 1210 | } |
| 1211 | catch (const gdb_exception_error &except) |
| 1212 | { |
| 1213 | /* Nothing, EXP remains NULL. */ |
| 1214 | } |
| 1215 | |
| 1216 | if (exp == NULL) |
| 1217 | return NULL; |
| 1218 | |
| 1219 | if (cstate.expout_tag_completion_type != TYPE_CODE_UNDEF) |
| 1220 | { |
| 1221 | *code = cstate.expout_tag_completion_type; |
| 1222 | *name = std::move (cstate.expout_completion_name); |
| 1223 | return NULL; |
| 1224 | } |
| 1225 | |
| 1226 | if (cstate.expout_last_struct == -1) |
| 1227 | return NULL; |
| 1228 | |
| 1229 | const char *fieldname = extract_field_op (exp.get (), &subexp); |
| 1230 | if (fieldname == NULL) |
| 1231 | { |
| 1232 | name->reset (); |
| 1233 | return NULL; |
| 1234 | } |
| 1235 | |
| 1236 | name->reset (xstrdup (fieldname)); |
| 1237 | /* This might throw an exception. If so, we want to let it |
| 1238 | propagate. */ |
| 1239 | val = evaluate_subexpression_type (exp.get (), subexp); |
| 1240 | |
| 1241 | return value_type (val); |
| 1242 | } |
| 1243 | |
| 1244 | /* A post-parser that does nothing. */ |
| 1245 | |
| 1246 | void |
| 1247 | null_post_parser (expression_up *exp, int void_context_p, int completin, |
| 1248 | innermost_block_tracker *tracker) |
| 1249 | { |
| 1250 | } |
| 1251 | |
| 1252 | /* Parse floating point value P of length LEN. |
| 1253 | Return false if invalid, true if valid. |
| 1254 | The successfully parsed number is stored in DATA in |
| 1255 | target format for floating-point type TYPE. |
| 1256 | |
| 1257 | NOTE: This accepts the floating point syntax that sscanf accepts. */ |
| 1258 | |
| 1259 | bool |
| 1260 | parse_float (const char *p, int len, |
| 1261 | const struct type *type, gdb_byte *data) |
| 1262 | { |
| 1263 | return target_float_from_string (data, type, std::string (p, len)); |
| 1264 | } |
| 1265 | \f |
| 1266 | /* This function avoids direct calls to fprintf |
| 1267 | in the parser generated debug code. */ |
| 1268 | void |
| 1269 | parser_fprintf (FILE *x, const char *y, ...) |
| 1270 | { |
| 1271 | va_list args; |
| 1272 | |
| 1273 | va_start (args, y); |
| 1274 | if (x == stderr) |
| 1275 | vfprintf_unfiltered (gdb_stderr, y, args); |
| 1276 | else |
| 1277 | { |
| 1278 | fprintf_unfiltered (gdb_stderr, " Unknown FILE used.\n"); |
| 1279 | vfprintf_unfiltered (gdb_stderr, y, args); |
| 1280 | } |
| 1281 | va_end (args); |
| 1282 | } |
| 1283 | |
| 1284 | /* Implementation of the exp_descriptor method operator_check. */ |
| 1285 | |
| 1286 | int |
| 1287 | operator_check_standard (struct expression *exp, int pos, |
| 1288 | int (*objfile_func) (struct objfile *objfile, |
| 1289 | void *data), |
| 1290 | void *data) |
| 1291 | { |
| 1292 | const union exp_element *const elts = exp->elts; |
| 1293 | struct type *type = NULL; |
| 1294 | struct objfile *objfile = NULL; |
| 1295 | |
| 1296 | /* Extended operators should have been already handled by exp_descriptor |
| 1297 | iterate method of its specific language. */ |
| 1298 | gdb_assert (elts[pos].opcode < OP_EXTENDED0); |
| 1299 | |
| 1300 | /* Track the callers of write_exp_elt_type for this table. */ |
| 1301 | |
| 1302 | switch (elts[pos].opcode) |
| 1303 | { |
| 1304 | case BINOP_VAL: |
| 1305 | case OP_COMPLEX: |
| 1306 | case OP_FLOAT: |
| 1307 | case OP_LONG: |
| 1308 | case OP_SCOPE: |
| 1309 | case OP_TYPE: |
| 1310 | case UNOP_CAST: |
| 1311 | case UNOP_MAX: |
| 1312 | case UNOP_MEMVAL: |
| 1313 | case UNOP_MIN: |
| 1314 | type = elts[pos + 1].type; |
| 1315 | break; |
| 1316 | |
| 1317 | case TYPE_INSTANCE: |
| 1318 | { |
| 1319 | LONGEST arg, nargs = elts[pos + 2].longconst; |
| 1320 | |
| 1321 | for (arg = 0; arg < nargs; arg++) |
| 1322 | { |
| 1323 | struct type *inst_type = elts[pos + 3 + arg].type; |
| 1324 | struct objfile *inst_objfile = TYPE_OBJFILE (inst_type); |
| 1325 | |
| 1326 | if (inst_objfile && (*objfile_func) (inst_objfile, data)) |
| 1327 | return 1; |
| 1328 | } |
| 1329 | } |
| 1330 | break; |
| 1331 | |
| 1332 | case OP_VAR_VALUE: |
| 1333 | { |
| 1334 | const struct block *const block = elts[pos + 1].block; |
| 1335 | const struct symbol *const symbol = elts[pos + 2].symbol; |
| 1336 | |
| 1337 | /* Check objfile where the variable itself is placed. |
| 1338 | SYMBOL_OBJ_SECTION (symbol) may be NULL. */ |
| 1339 | if ((*objfile_func) (symbol_objfile (symbol), data)) |
| 1340 | return 1; |
| 1341 | |
| 1342 | /* Check objfile where is placed the code touching the variable. */ |
| 1343 | objfile = lookup_objfile_from_block (block); |
| 1344 | |
| 1345 | type = SYMBOL_TYPE (symbol); |
| 1346 | } |
| 1347 | break; |
| 1348 | case OP_VAR_MSYM_VALUE: |
| 1349 | objfile = elts[pos + 1].objfile; |
| 1350 | break; |
| 1351 | } |
| 1352 | |
| 1353 | /* Invoke callbacks for TYPE and OBJFILE if they were set as non-NULL. */ |
| 1354 | |
| 1355 | if (type && TYPE_OBJFILE (type) |
| 1356 | && (*objfile_func) (TYPE_OBJFILE (type), data)) |
| 1357 | return 1; |
| 1358 | if (objfile && (*objfile_func) (objfile, data)) |
| 1359 | return 1; |
| 1360 | |
| 1361 | return 0; |
| 1362 | } |
| 1363 | |
| 1364 | /* Call OBJFILE_FUNC for any objfile found being referenced by EXP. |
| 1365 | OBJFILE_FUNC is never called with NULL OBJFILE. OBJFILE_FUNC get |
| 1366 | passed an arbitrary caller supplied DATA pointer. If OBJFILE_FUNC |
| 1367 | returns non-zero value then (any other) non-zero value is immediately |
| 1368 | returned to the caller. Otherwise zero is returned after iterating |
| 1369 | through whole EXP. */ |
| 1370 | |
| 1371 | static int |
| 1372 | exp_iterate (struct expression *exp, |
| 1373 | int (*objfile_func) (struct objfile *objfile, void *data), |
| 1374 | void *data) |
| 1375 | { |
| 1376 | int endpos; |
| 1377 | |
| 1378 | for (endpos = exp->nelts; endpos > 0; ) |
| 1379 | { |
| 1380 | int pos, args, oplen = 0; |
| 1381 | |
| 1382 | operator_length (exp, endpos, &oplen, &args); |
| 1383 | gdb_assert (oplen > 0); |
| 1384 | |
| 1385 | pos = endpos - oplen; |
| 1386 | if (exp->language_defn->la_exp_desc->operator_check (exp, pos, |
| 1387 | objfile_func, data)) |
| 1388 | return 1; |
| 1389 | |
| 1390 | endpos = pos; |
| 1391 | } |
| 1392 | |
| 1393 | return 0; |
| 1394 | } |
| 1395 | |
| 1396 | /* Helper for exp_uses_objfile. */ |
| 1397 | |
| 1398 | static int |
| 1399 | exp_uses_objfile_iter (struct objfile *exp_objfile, void *objfile_voidp) |
| 1400 | { |
| 1401 | struct objfile *objfile = (struct objfile *) objfile_voidp; |
| 1402 | |
| 1403 | if (exp_objfile->separate_debug_objfile_backlink) |
| 1404 | exp_objfile = exp_objfile->separate_debug_objfile_backlink; |
| 1405 | |
| 1406 | return exp_objfile == objfile; |
| 1407 | } |
| 1408 | |
| 1409 | /* Return 1 if EXP uses OBJFILE (and will become dangling when OBJFILE |
| 1410 | is unloaded), otherwise return 0. OBJFILE must not be a separate debug info |
| 1411 | file. */ |
| 1412 | |
| 1413 | int |
| 1414 | exp_uses_objfile (struct expression *exp, struct objfile *objfile) |
| 1415 | { |
| 1416 | gdb_assert (objfile->separate_debug_objfile_backlink == NULL); |
| 1417 | |
| 1418 | return exp_iterate (exp, exp_uses_objfile_iter, objfile); |
| 1419 | } |
| 1420 | |
| 1421 | /* Reallocate the `expout' pointer inside PS so that it can accommodate |
| 1422 | at least LENELT expression elements. This function does nothing if |
| 1423 | there is enough room for the elements. */ |
| 1424 | |
| 1425 | static void |
| 1426 | increase_expout_size (struct expr_builder *ps, size_t lenelt) |
| 1427 | { |
| 1428 | if ((ps->expout_ptr + lenelt) >= ps->expout_size) |
| 1429 | { |
| 1430 | ps->expout_size = std::max (ps->expout_size * 2, |
| 1431 | ps->expout_ptr + lenelt + 10); |
| 1432 | ps->expout.reset (XRESIZEVAR (expression, |
| 1433 | ps->expout.release (), |
| 1434 | (sizeof (struct expression) |
| 1435 | + EXP_ELEM_TO_BYTES (ps->expout_size)))); |
| 1436 | } |
| 1437 | } |
| 1438 | |
| 1439 | void _initialize_parse (); |
| 1440 | void |
| 1441 | _initialize_parse () |
| 1442 | { |
| 1443 | add_setshow_zuinteger_cmd ("expression", class_maintenance, |
| 1444 | &expressiondebug, |
| 1445 | _("Set expression debugging."), |
| 1446 | _("Show expression debugging."), |
| 1447 | _("When non-zero, the internal representation " |
| 1448 | "of expressions will be printed."), |
| 1449 | NULL, |
| 1450 | show_expressiondebug, |
| 1451 | &setdebuglist, &showdebuglist); |
| 1452 | add_setshow_boolean_cmd ("parser", class_maintenance, |
| 1453 | &parser_debug, |
| 1454 | _("Set parser debugging."), |
| 1455 | _("Show parser debugging."), |
| 1456 | _("When non-zero, expression parser " |
| 1457 | "tracing will be enabled."), |
| 1458 | NULL, |
| 1459 | show_parserdebug, |
| 1460 | &setdebuglist, &showdebuglist); |
| 1461 | } |