| 1 | /* Parse expressions for GDB. |
| 2 | |
| 3 | Copyright (C) 1986, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, |
| 4 | 1998, 1999, 2000, 2001, 2004, 2005, 2007, 2008, 2009, 2010 |
| 5 | Free Software Foundation, Inc. |
| 6 | |
| 7 | Modified from expread.y by the Department of Computer Science at the |
| 8 | State University of New York at Buffalo, 1991. |
| 9 | |
| 10 | This file is part of GDB. |
| 11 | |
| 12 | This program is free software; you can redistribute it and/or modify |
| 13 | it under the terms of the GNU General Public License as published by |
| 14 | the Free Software Foundation; either version 3 of the License, or |
| 15 | (at your option) any later version. |
| 16 | |
| 17 | This program is distributed in the hope that it will be useful, |
| 18 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | GNU General Public License for more details. |
| 21 | |
| 22 | You should have received a copy of the GNU General Public License |
| 23 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 24 | |
| 25 | /* Parse an expression from text in a string, |
| 26 | and return the result as a struct expression pointer. |
| 27 | That structure contains arithmetic operations in reverse polish, |
| 28 | with constants represented by operations that are followed by special data. |
| 29 | See expression.h for the details of the format. |
| 30 | What is important here is that it can be built up sequentially |
| 31 | during the process of parsing; the lower levels of the tree always |
| 32 | come first in the result. */ |
| 33 | |
| 34 | #include "defs.h" |
| 35 | #include <ctype.h> |
| 36 | #include "arch-utils.h" |
| 37 | #include "gdb_string.h" |
| 38 | #include "symtab.h" |
| 39 | #include "gdbtypes.h" |
| 40 | #include "frame.h" |
| 41 | #include "expression.h" |
| 42 | #include "value.h" |
| 43 | #include "command.h" |
| 44 | #include "language.h" |
| 45 | #include "f-lang.h" |
| 46 | #include "parser-defs.h" |
| 47 | #include "gdbcmd.h" |
| 48 | #include "symfile.h" /* for overlay functions */ |
| 49 | #include "inferior.h" |
| 50 | #include "doublest.h" |
| 51 | #include "gdb_assert.h" |
| 52 | #include "block.h" |
| 53 | #include "source.h" |
| 54 | #include "objfiles.h" |
| 55 | #include "exceptions.h" |
| 56 | #include "user-regs.h" |
| 57 | |
| 58 | /* Standard set of definitions for printing, dumping, prefixifying, |
| 59 | * and evaluating expressions. */ |
| 60 | |
| 61 | const struct exp_descriptor exp_descriptor_standard = |
| 62 | { |
| 63 | print_subexp_standard, |
| 64 | operator_length_standard, |
| 65 | op_name_standard, |
| 66 | dump_subexp_body_standard, |
| 67 | evaluate_subexp_standard |
| 68 | }; |
| 69 | \f |
| 70 | /* Global variables declared in parser-defs.h (and commented there). */ |
| 71 | struct expression *expout; |
| 72 | int expout_size; |
| 73 | int expout_ptr; |
| 74 | struct block *expression_context_block; |
| 75 | CORE_ADDR expression_context_pc; |
| 76 | struct block *innermost_block; |
| 77 | int arglist_len; |
| 78 | union type_stack_elt *type_stack; |
| 79 | int type_stack_depth, type_stack_size; |
| 80 | char *lexptr; |
| 81 | char *prev_lexptr; |
| 82 | int paren_depth; |
| 83 | int comma_terminates; |
| 84 | |
| 85 | /* True if parsing an expression to find a field reference. This is |
| 86 | only used by completion. */ |
| 87 | int in_parse_field; |
| 88 | |
| 89 | /* The index of the last struct expression directly before a '.' or |
| 90 | '->'. This is set when parsing and is only used when completing a |
| 91 | field name. It is -1 if no dereference operation was found. */ |
| 92 | static int expout_last_struct = -1; |
| 93 | |
| 94 | /* A temporary buffer for identifiers, so we can null-terminate them. |
| 95 | |
| 96 | We allocate this with xrealloc. parse_exp_1 used to allocate with |
| 97 | alloca, using the size of the whole expression as a conservative |
| 98 | estimate of the space needed. However, macro expansion can |
| 99 | introduce names longer than the original expression; there's no |
| 100 | practical way to know beforehand how large that might be. */ |
| 101 | char *namecopy; |
| 102 | size_t namecopy_size; |
| 103 | \f |
| 104 | static int expressiondebug = 0; |
| 105 | static void |
| 106 | show_expressiondebug (struct ui_file *file, int from_tty, |
| 107 | struct cmd_list_element *c, const char *value) |
| 108 | { |
| 109 | fprintf_filtered (file, _("Expression debugging is %s.\n"), value); |
| 110 | } |
| 111 | |
| 112 | static void free_funcalls (void *ignore); |
| 113 | |
| 114 | static int prefixify_expression (struct expression *); |
| 115 | |
| 116 | static int prefixify_subexp (struct expression *, struct expression *, int, |
| 117 | int); |
| 118 | |
| 119 | static struct expression *parse_exp_in_context (char **, struct block *, int, |
| 120 | int, int *); |
| 121 | |
| 122 | void _initialize_parse (void); |
| 123 | |
| 124 | /* Data structure for saving values of arglist_len for function calls whose |
| 125 | arguments contain other function calls. */ |
| 126 | |
| 127 | struct funcall |
| 128 | { |
| 129 | struct funcall *next; |
| 130 | int arglist_len; |
| 131 | }; |
| 132 | |
| 133 | static struct funcall *funcall_chain; |
| 134 | |
| 135 | /* Begin counting arguments for a function call, |
| 136 | saving the data about any containing call. */ |
| 137 | |
| 138 | void |
| 139 | start_arglist (void) |
| 140 | { |
| 141 | struct funcall *new; |
| 142 | |
| 143 | new = (struct funcall *) xmalloc (sizeof (struct funcall)); |
| 144 | new->next = funcall_chain; |
| 145 | new->arglist_len = arglist_len; |
| 146 | arglist_len = 0; |
| 147 | funcall_chain = new; |
| 148 | } |
| 149 | |
| 150 | /* Return the number of arguments in a function call just terminated, |
| 151 | and restore the data for the containing function call. */ |
| 152 | |
| 153 | int |
| 154 | end_arglist (void) |
| 155 | { |
| 156 | int val = arglist_len; |
| 157 | struct funcall *call = funcall_chain; |
| 158 | funcall_chain = call->next; |
| 159 | arglist_len = call->arglist_len; |
| 160 | xfree (call); |
| 161 | return val; |
| 162 | } |
| 163 | |
| 164 | /* Free everything in the funcall chain. |
| 165 | Used when there is an error inside parsing. */ |
| 166 | |
| 167 | static void |
| 168 | free_funcalls (void *ignore) |
| 169 | { |
| 170 | struct funcall *call, *next; |
| 171 | |
| 172 | for (call = funcall_chain; call; call = next) |
| 173 | { |
| 174 | next = call->next; |
| 175 | xfree (call); |
| 176 | } |
| 177 | } |
| 178 | \f |
| 179 | /* This page contains the functions for adding data to the struct expression |
| 180 | being constructed. */ |
| 181 | |
| 182 | /* Add one element to the end of the expression. */ |
| 183 | |
| 184 | /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into |
| 185 | a register through here */ |
| 186 | |
| 187 | void |
| 188 | write_exp_elt (union exp_element expelt) |
| 189 | { |
| 190 | if (expout_ptr >= expout_size) |
| 191 | { |
| 192 | expout_size *= 2; |
| 193 | expout = (struct expression *) |
| 194 | xrealloc ((char *) expout, sizeof (struct expression) |
| 195 | + EXP_ELEM_TO_BYTES (expout_size)); |
| 196 | } |
| 197 | expout->elts[expout_ptr++] = expelt; |
| 198 | } |
| 199 | |
| 200 | void |
| 201 | write_exp_elt_opcode (enum exp_opcode expelt) |
| 202 | { |
| 203 | union exp_element tmp; |
| 204 | memset (&tmp, 0, sizeof (union exp_element)); |
| 205 | |
| 206 | tmp.opcode = expelt; |
| 207 | |
| 208 | write_exp_elt (tmp); |
| 209 | } |
| 210 | |
| 211 | void |
| 212 | write_exp_elt_sym (struct symbol *expelt) |
| 213 | { |
| 214 | union exp_element tmp; |
| 215 | memset (&tmp, 0, sizeof (union exp_element)); |
| 216 | |
| 217 | tmp.symbol = expelt; |
| 218 | |
| 219 | write_exp_elt (tmp); |
| 220 | } |
| 221 | |
| 222 | void |
| 223 | write_exp_elt_block (struct block *b) |
| 224 | { |
| 225 | union exp_element tmp; |
| 226 | memset (&tmp, 0, sizeof (union exp_element)); |
| 227 | tmp.block = b; |
| 228 | write_exp_elt (tmp); |
| 229 | } |
| 230 | |
| 231 | void |
| 232 | write_exp_elt_objfile (struct objfile *objfile) |
| 233 | { |
| 234 | union exp_element tmp; |
| 235 | memset (&tmp, 0, sizeof (union exp_element)); |
| 236 | tmp.objfile = objfile; |
| 237 | write_exp_elt (tmp); |
| 238 | } |
| 239 | |
| 240 | void |
| 241 | write_exp_elt_longcst (LONGEST expelt) |
| 242 | { |
| 243 | union exp_element tmp; |
| 244 | memset (&tmp, 0, sizeof (union exp_element)); |
| 245 | |
| 246 | tmp.longconst = expelt; |
| 247 | |
| 248 | write_exp_elt (tmp); |
| 249 | } |
| 250 | |
| 251 | void |
| 252 | write_exp_elt_dblcst (DOUBLEST expelt) |
| 253 | { |
| 254 | union exp_element tmp; |
| 255 | memset (&tmp, 0, sizeof (union exp_element)); |
| 256 | |
| 257 | tmp.doubleconst = expelt; |
| 258 | |
| 259 | write_exp_elt (tmp); |
| 260 | } |
| 261 | |
| 262 | void |
| 263 | write_exp_elt_decfloatcst (gdb_byte expelt[16]) |
| 264 | { |
| 265 | union exp_element tmp; |
| 266 | int index; |
| 267 | |
| 268 | for (index = 0; index < 16; index++) |
| 269 | tmp.decfloatconst[index] = expelt[index]; |
| 270 | |
| 271 | write_exp_elt (tmp); |
| 272 | } |
| 273 | |
| 274 | void |
| 275 | write_exp_elt_type (struct type *expelt) |
| 276 | { |
| 277 | union exp_element tmp; |
| 278 | memset (&tmp, 0, sizeof (union exp_element)); |
| 279 | |
| 280 | tmp.type = expelt; |
| 281 | |
| 282 | write_exp_elt (tmp); |
| 283 | } |
| 284 | |
| 285 | void |
| 286 | write_exp_elt_intern (struct internalvar *expelt) |
| 287 | { |
| 288 | union exp_element tmp; |
| 289 | memset (&tmp, 0, sizeof (union exp_element)); |
| 290 | |
| 291 | tmp.internalvar = expelt; |
| 292 | |
| 293 | write_exp_elt (tmp); |
| 294 | } |
| 295 | |
| 296 | /* Add a string constant to the end of the expression. |
| 297 | |
| 298 | String constants are stored by first writing an expression element |
| 299 | that contains the length of the string, then stuffing the string |
| 300 | constant itself into however many expression elements are needed |
| 301 | to hold it, and then writing another expression element that contains |
| 302 | the length of the string. I.E. an expression element at each end of |
| 303 | the string records the string length, so you can skip over the |
| 304 | expression elements containing the actual string bytes from either |
| 305 | end of the string. Note that this also allows gdb to handle |
| 306 | strings with embedded null bytes, as is required for some languages. |
| 307 | |
| 308 | Don't be fooled by the fact that the string is null byte terminated, |
| 309 | this is strictly for the convenience of debugging gdb itself. |
| 310 | Gdb does not depend up the string being null terminated, since the |
| 311 | actual length is recorded in expression elements at each end of the |
| 312 | string. The null byte is taken into consideration when computing how |
| 313 | many expression elements are required to hold the string constant, of |
| 314 | course. */ |
| 315 | |
| 316 | |
| 317 | void |
| 318 | write_exp_string (struct stoken str) |
| 319 | { |
| 320 | int len = str.length; |
| 321 | int lenelt; |
| 322 | char *strdata; |
| 323 | |
| 324 | /* Compute the number of expression elements required to hold the string |
| 325 | (including a null byte terminator), along with one expression element |
| 326 | at each end to record the actual string length (not including the |
| 327 | null byte terminator). */ |
| 328 | |
| 329 | lenelt = 2 + BYTES_TO_EXP_ELEM (len + 1); |
| 330 | |
| 331 | /* Ensure that we have enough available expression elements to store |
| 332 | everything. */ |
| 333 | |
| 334 | if ((expout_ptr + lenelt) >= expout_size) |
| 335 | { |
| 336 | expout_size = max (expout_size * 2, expout_ptr + lenelt + 10); |
| 337 | expout = (struct expression *) |
| 338 | xrealloc ((char *) expout, (sizeof (struct expression) |
| 339 | + EXP_ELEM_TO_BYTES (expout_size))); |
| 340 | } |
| 341 | |
| 342 | /* Write the leading length expression element (which advances the current |
| 343 | expression element index), then write the string constant followed by a |
| 344 | terminating null byte, and then write the trailing length expression |
| 345 | element. */ |
| 346 | |
| 347 | write_exp_elt_longcst ((LONGEST) len); |
| 348 | strdata = (char *) &expout->elts[expout_ptr]; |
| 349 | memcpy (strdata, str.ptr, len); |
| 350 | *(strdata + len) = '\0'; |
| 351 | expout_ptr += lenelt - 2; |
| 352 | write_exp_elt_longcst ((LONGEST) len); |
| 353 | } |
| 354 | |
| 355 | /* Add a vector of string constants to the end of the expression. |
| 356 | |
| 357 | This adds an OP_STRING operation, but encodes the contents |
| 358 | differently from write_exp_string. The language is expected to |
| 359 | handle evaluation of this expression itself. |
| 360 | |
| 361 | After the usual OP_STRING header, TYPE is written into the |
| 362 | expression as a long constant. The interpretation of this field is |
| 363 | up to the language evaluator. |
| 364 | |
| 365 | Next, each string in VEC is written. The length is written as a |
| 366 | long constant, followed by the contents of the string. */ |
| 367 | |
| 368 | void |
| 369 | write_exp_string_vector (int type, struct stoken_vector *vec) |
| 370 | { |
| 371 | int i, n_slots, len; |
| 372 | |
| 373 | /* Compute the size. We compute the size in number of slots to |
| 374 | avoid issues with string padding. */ |
| 375 | n_slots = 0; |
| 376 | for (i = 0; i < vec->len; ++i) |
| 377 | { |
| 378 | /* One slot for the length of this element, plus the number of |
| 379 | slots needed for this string. */ |
| 380 | n_slots += 1 + BYTES_TO_EXP_ELEM (vec->tokens[i].length); |
| 381 | } |
| 382 | |
| 383 | /* One more slot for the type of the string. */ |
| 384 | ++n_slots; |
| 385 | |
| 386 | /* Now compute a phony string length. */ |
| 387 | len = EXP_ELEM_TO_BYTES (n_slots) - 1; |
| 388 | |
| 389 | n_slots += 4; |
| 390 | if ((expout_ptr + n_slots) >= expout_size) |
| 391 | { |
| 392 | expout_size = max (expout_size * 2, expout_ptr + n_slots + 10); |
| 393 | expout = (struct expression *) |
| 394 | xrealloc ((char *) expout, (sizeof (struct expression) |
| 395 | + EXP_ELEM_TO_BYTES (expout_size))); |
| 396 | } |
| 397 | |
| 398 | write_exp_elt_opcode (OP_STRING); |
| 399 | write_exp_elt_longcst (len); |
| 400 | write_exp_elt_longcst (type); |
| 401 | |
| 402 | for (i = 0; i < vec->len; ++i) |
| 403 | { |
| 404 | write_exp_elt_longcst (vec->tokens[i].length); |
| 405 | memcpy (&expout->elts[expout_ptr], vec->tokens[i].ptr, |
| 406 | vec->tokens[i].length); |
| 407 | expout_ptr += BYTES_TO_EXP_ELEM (vec->tokens[i].length); |
| 408 | } |
| 409 | |
| 410 | write_exp_elt_longcst (len); |
| 411 | write_exp_elt_opcode (OP_STRING); |
| 412 | } |
| 413 | |
| 414 | /* Add a bitstring constant to the end of the expression. |
| 415 | |
| 416 | Bitstring constants are stored by first writing an expression element |
| 417 | that contains the length of the bitstring (in bits), then stuffing the |
| 418 | bitstring constant itself into however many expression elements are |
| 419 | needed to hold it, and then writing another expression element that |
| 420 | contains the length of the bitstring. I.E. an expression element at |
| 421 | each end of the bitstring records the bitstring length, so you can skip |
| 422 | over the expression elements containing the actual bitstring bytes from |
| 423 | either end of the bitstring. */ |
| 424 | |
| 425 | void |
| 426 | write_exp_bitstring (struct stoken str) |
| 427 | { |
| 428 | int bits = str.length; /* length in bits */ |
| 429 | int len = (bits + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT; |
| 430 | int lenelt; |
| 431 | char *strdata; |
| 432 | |
| 433 | /* Compute the number of expression elements required to hold the bitstring, |
| 434 | along with one expression element at each end to record the actual |
| 435 | bitstring length in bits. */ |
| 436 | |
| 437 | lenelt = 2 + BYTES_TO_EXP_ELEM (len); |
| 438 | |
| 439 | /* Ensure that we have enough available expression elements to store |
| 440 | everything. */ |
| 441 | |
| 442 | if ((expout_ptr + lenelt) >= expout_size) |
| 443 | { |
| 444 | expout_size = max (expout_size * 2, expout_ptr + lenelt + 10); |
| 445 | expout = (struct expression *) |
| 446 | xrealloc ((char *) expout, (sizeof (struct expression) |
| 447 | + EXP_ELEM_TO_BYTES (expout_size))); |
| 448 | } |
| 449 | |
| 450 | /* Write the leading length expression element (which advances the current |
| 451 | expression element index), then write the bitstring constant, and then |
| 452 | write the trailing length expression element. */ |
| 453 | |
| 454 | write_exp_elt_longcst ((LONGEST) bits); |
| 455 | strdata = (char *) &expout->elts[expout_ptr]; |
| 456 | memcpy (strdata, str.ptr, len); |
| 457 | expout_ptr += lenelt - 2; |
| 458 | write_exp_elt_longcst ((LONGEST) bits); |
| 459 | } |
| 460 | |
| 461 | /* Add the appropriate elements for a minimal symbol to the end of |
| 462 | the expression. */ |
| 463 | |
| 464 | void |
| 465 | write_exp_msymbol (struct minimal_symbol *msymbol) |
| 466 | { |
| 467 | struct objfile *objfile = msymbol_objfile (msymbol); |
| 468 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
| 469 | |
| 470 | CORE_ADDR addr = SYMBOL_VALUE_ADDRESS (msymbol); |
| 471 | struct obj_section *section = SYMBOL_OBJ_SECTION (msymbol); |
| 472 | enum minimal_symbol_type type = MSYMBOL_TYPE (msymbol); |
| 473 | CORE_ADDR pc; |
| 474 | |
| 475 | /* The minimal symbol might point to a function descriptor; |
| 476 | resolve it to the actual code address instead. */ |
| 477 | pc = gdbarch_convert_from_func_ptr_addr (gdbarch, addr, ¤t_target); |
| 478 | if (pc != addr) |
| 479 | { |
| 480 | /* In this case, assume we have a code symbol instead of |
| 481 | a data symbol. */ |
| 482 | type = mst_text; |
| 483 | section = NULL; |
| 484 | addr = pc; |
| 485 | } |
| 486 | |
| 487 | if (overlay_debugging) |
| 488 | addr = symbol_overlayed_address (addr, section); |
| 489 | |
| 490 | write_exp_elt_opcode (OP_LONG); |
| 491 | /* Let's make the type big enough to hold a 64-bit address. */ |
| 492 | write_exp_elt_type (objfile_type (objfile)->builtin_core_addr); |
| 493 | write_exp_elt_longcst ((LONGEST) addr); |
| 494 | write_exp_elt_opcode (OP_LONG); |
| 495 | |
| 496 | if (section && section->the_bfd_section->flags & SEC_THREAD_LOCAL) |
| 497 | { |
| 498 | write_exp_elt_opcode (UNOP_MEMVAL_TLS); |
| 499 | write_exp_elt_objfile (objfile); |
| 500 | write_exp_elt_type (objfile_type (objfile)->nodebug_tls_symbol); |
| 501 | write_exp_elt_opcode (UNOP_MEMVAL_TLS); |
| 502 | return; |
| 503 | } |
| 504 | |
| 505 | write_exp_elt_opcode (UNOP_MEMVAL); |
| 506 | switch (type) |
| 507 | { |
| 508 | case mst_text: |
| 509 | case mst_file_text: |
| 510 | case mst_solib_trampoline: |
| 511 | write_exp_elt_type (objfile_type (objfile)->nodebug_text_symbol); |
| 512 | break; |
| 513 | |
| 514 | case mst_data: |
| 515 | case mst_file_data: |
| 516 | case mst_bss: |
| 517 | case mst_file_bss: |
| 518 | write_exp_elt_type (objfile_type (objfile)->nodebug_data_symbol); |
| 519 | break; |
| 520 | |
| 521 | default: |
| 522 | write_exp_elt_type (objfile_type (objfile)->nodebug_unknown_symbol); |
| 523 | break; |
| 524 | } |
| 525 | write_exp_elt_opcode (UNOP_MEMVAL); |
| 526 | } |
| 527 | |
| 528 | /* Mark the current index as the starting location of a structure |
| 529 | expression. This is used when completing on field names. */ |
| 530 | |
| 531 | void |
| 532 | mark_struct_expression (void) |
| 533 | { |
| 534 | expout_last_struct = expout_ptr; |
| 535 | } |
| 536 | |
| 537 | \f |
| 538 | /* Recognize tokens that start with '$'. These include: |
| 539 | |
| 540 | $regname A native register name or a "standard |
| 541 | register name". |
| 542 | |
| 543 | $variable A convenience variable with a name chosen |
| 544 | by the user. |
| 545 | |
| 546 | $digits Value history with index <digits>, starting |
| 547 | from the first value which has index 1. |
| 548 | |
| 549 | $$digits Value history with index <digits> relative |
| 550 | to the last value. I.E. $$0 is the last |
| 551 | value, $$1 is the one previous to that, $$2 |
| 552 | is the one previous to $$1, etc. |
| 553 | |
| 554 | $ | $0 | $$0 The last value in the value history. |
| 555 | |
| 556 | $$ An abbreviation for the second to the last |
| 557 | value in the value history, I.E. $$1 |
| 558 | |
| 559 | */ |
| 560 | |
| 561 | void |
| 562 | write_dollar_variable (struct stoken str) |
| 563 | { |
| 564 | struct symbol *sym = NULL; |
| 565 | struct minimal_symbol *msym = NULL; |
| 566 | struct internalvar *isym = NULL; |
| 567 | |
| 568 | /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1) |
| 569 | and $$digits (equivalent to $<-digits> if you could type that). */ |
| 570 | |
| 571 | int negate = 0; |
| 572 | int i = 1; |
| 573 | /* Double dollar means negate the number and add -1 as well. |
| 574 | Thus $$ alone means -1. */ |
| 575 | if (str.length >= 2 && str.ptr[1] == '$') |
| 576 | { |
| 577 | negate = 1; |
| 578 | i = 2; |
| 579 | } |
| 580 | if (i == str.length) |
| 581 | { |
| 582 | /* Just dollars (one or two) */ |
| 583 | i = -negate; |
| 584 | goto handle_last; |
| 585 | } |
| 586 | /* Is the rest of the token digits? */ |
| 587 | for (; i < str.length; i++) |
| 588 | if (!(str.ptr[i] >= '0' && str.ptr[i] <= '9')) |
| 589 | break; |
| 590 | if (i == str.length) |
| 591 | { |
| 592 | i = atoi (str.ptr + 1 + negate); |
| 593 | if (negate) |
| 594 | i = -i; |
| 595 | goto handle_last; |
| 596 | } |
| 597 | |
| 598 | /* Handle tokens that refer to machine registers: |
| 599 | $ followed by a register name. */ |
| 600 | i = user_reg_map_name_to_regnum (parse_gdbarch, |
| 601 | str.ptr + 1, str.length - 1); |
| 602 | if (i >= 0) |
| 603 | goto handle_register; |
| 604 | |
| 605 | /* Any names starting with $ are probably debugger internal variables. */ |
| 606 | |
| 607 | isym = lookup_only_internalvar (copy_name (str) + 1); |
| 608 | if (isym) |
| 609 | { |
| 610 | write_exp_elt_opcode (OP_INTERNALVAR); |
| 611 | write_exp_elt_intern (isym); |
| 612 | write_exp_elt_opcode (OP_INTERNALVAR); |
| 613 | return; |
| 614 | } |
| 615 | |
| 616 | /* On some systems, such as HP-UX and hppa-linux, certain system routines |
| 617 | have names beginning with $ or $$. Check for those, first. */ |
| 618 | |
| 619 | sym = lookup_symbol (copy_name (str), (struct block *) NULL, |
| 620 | VAR_DOMAIN, (int *) NULL); |
| 621 | if (sym) |
| 622 | { |
| 623 | write_exp_elt_opcode (OP_VAR_VALUE); |
| 624 | write_exp_elt_block (block_found); /* set by lookup_symbol */ |
| 625 | write_exp_elt_sym (sym); |
| 626 | write_exp_elt_opcode (OP_VAR_VALUE); |
| 627 | return; |
| 628 | } |
| 629 | msym = lookup_minimal_symbol (copy_name (str), NULL, NULL); |
| 630 | if (msym) |
| 631 | { |
| 632 | write_exp_msymbol (msym); |
| 633 | return; |
| 634 | } |
| 635 | |
| 636 | /* Any other names are assumed to be debugger internal variables. */ |
| 637 | |
| 638 | write_exp_elt_opcode (OP_INTERNALVAR); |
| 639 | write_exp_elt_intern (create_internalvar (copy_name (str) + 1)); |
| 640 | write_exp_elt_opcode (OP_INTERNALVAR); |
| 641 | return; |
| 642 | handle_last: |
| 643 | write_exp_elt_opcode (OP_LAST); |
| 644 | write_exp_elt_longcst ((LONGEST) i); |
| 645 | write_exp_elt_opcode (OP_LAST); |
| 646 | return; |
| 647 | handle_register: |
| 648 | write_exp_elt_opcode (OP_REGISTER); |
| 649 | str.length--; |
| 650 | str.ptr++; |
| 651 | write_exp_string (str); |
| 652 | write_exp_elt_opcode (OP_REGISTER); |
| 653 | return; |
| 654 | } |
| 655 | |
| 656 | |
| 657 | char * |
| 658 | find_template_name_end (char *p) |
| 659 | { |
| 660 | int depth = 1; |
| 661 | int just_seen_right = 0; |
| 662 | int just_seen_colon = 0; |
| 663 | int just_seen_space = 0; |
| 664 | |
| 665 | if (!p || (*p != '<')) |
| 666 | return 0; |
| 667 | |
| 668 | while (*++p) |
| 669 | { |
| 670 | switch (*p) |
| 671 | { |
| 672 | case '\'': |
| 673 | case '\"': |
| 674 | case '{': |
| 675 | case '}': |
| 676 | /* In future, may want to allow these?? */ |
| 677 | return 0; |
| 678 | case '<': |
| 679 | depth++; /* start nested template */ |
| 680 | if (just_seen_colon || just_seen_right || just_seen_space) |
| 681 | return 0; /* but not after : or :: or > or space */ |
| 682 | break; |
| 683 | case '>': |
| 684 | if (just_seen_colon || just_seen_right) |
| 685 | return 0; /* end a (nested?) template */ |
| 686 | just_seen_right = 1; /* but not after : or :: */ |
| 687 | if (--depth == 0) /* also disallow >>, insist on > > */ |
| 688 | return ++p; /* if outermost ended, return */ |
| 689 | break; |
| 690 | case ':': |
| 691 | if (just_seen_space || (just_seen_colon > 1)) |
| 692 | return 0; /* nested class spec coming up */ |
| 693 | just_seen_colon++; /* we allow :: but not :::: */ |
| 694 | break; |
| 695 | case ' ': |
| 696 | break; |
| 697 | default: |
| 698 | if (!((*p >= 'a' && *p <= 'z') || /* allow token chars */ |
| 699 | (*p >= 'A' && *p <= 'Z') || |
| 700 | (*p >= '0' && *p <= '9') || |
| 701 | (*p == '_') || (*p == ',') || /* commas for template args */ |
| 702 | (*p == '&') || (*p == '*') || /* pointer and ref types */ |
| 703 | (*p == '(') || (*p == ')') || /* function types */ |
| 704 | (*p == '[') || (*p == ']'))) /* array types */ |
| 705 | return 0; |
| 706 | } |
| 707 | if (*p != ' ') |
| 708 | just_seen_space = 0; |
| 709 | if (*p != ':') |
| 710 | just_seen_colon = 0; |
| 711 | if (*p != '>') |
| 712 | just_seen_right = 0; |
| 713 | } |
| 714 | return 0; |
| 715 | } |
| 716 | \f |
| 717 | |
| 718 | |
| 719 | /* Return a null-terminated temporary copy of the name |
| 720 | of a string token. */ |
| 721 | |
| 722 | char * |
| 723 | copy_name (struct stoken token) |
| 724 | { |
| 725 | /* Make sure there's enough space for the token. */ |
| 726 | if (namecopy_size < token.length + 1) |
| 727 | { |
| 728 | namecopy_size = token.length + 1; |
| 729 | namecopy = xrealloc (namecopy, token.length + 1); |
| 730 | } |
| 731 | |
| 732 | memcpy (namecopy, token.ptr, token.length); |
| 733 | namecopy[token.length] = 0; |
| 734 | |
| 735 | return namecopy; |
| 736 | } |
| 737 | \f |
| 738 | /* Reverse an expression from suffix form (in which it is constructed) |
| 739 | to prefix form (in which we can conveniently print or execute it). |
| 740 | Ordinarily this always returns -1. However, if EXPOUT_LAST_STRUCT |
| 741 | is not -1 (i.e., we are trying to complete a field name), it will |
| 742 | return the index of the subexpression which is the left-hand-side |
| 743 | of the struct operation at EXPOUT_LAST_STRUCT. */ |
| 744 | |
| 745 | static int |
| 746 | prefixify_expression (struct expression *expr) |
| 747 | { |
| 748 | int len = sizeof (struct expression) + EXP_ELEM_TO_BYTES (expr->nelts); |
| 749 | struct expression *temp; |
| 750 | int inpos = expr->nelts, outpos = 0; |
| 751 | |
| 752 | temp = (struct expression *) alloca (len); |
| 753 | |
| 754 | /* Copy the original expression into temp. */ |
| 755 | memcpy (temp, expr, len); |
| 756 | |
| 757 | return prefixify_subexp (temp, expr, inpos, outpos); |
| 758 | } |
| 759 | |
| 760 | /* Return the number of exp_elements in the postfix subexpression |
| 761 | of EXPR whose operator is at index ENDPOS - 1 in EXPR. */ |
| 762 | |
| 763 | int |
| 764 | length_of_subexp (struct expression *expr, int endpos) |
| 765 | { |
| 766 | int oplen, args, i; |
| 767 | |
| 768 | operator_length (expr, endpos, &oplen, &args); |
| 769 | |
| 770 | while (args > 0) |
| 771 | { |
| 772 | oplen += length_of_subexp (expr, endpos - oplen); |
| 773 | args--; |
| 774 | } |
| 775 | |
| 776 | return oplen; |
| 777 | } |
| 778 | |
| 779 | /* Sets *OPLENP to the length of the operator whose (last) index is |
| 780 | ENDPOS - 1 in EXPR, and sets *ARGSP to the number of arguments that |
| 781 | operator takes. */ |
| 782 | |
| 783 | void |
| 784 | operator_length (struct expression *expr, int endpos, int *oplenp, int *argsp) |
| 785 | { |
| 786 | expr->language_defn->la_exp_desc->operator_length (expr, endpos, |
| 787 | oplenp, argsp); |
| 788 | } |
| 789 | |
| 790 | /* Default value for operator_length in exp_descriptor vectors. */ |
| 791 | |
| 792 | void |
| 793 | operator_length_standard (struct expression *expr, int endpos, |
| 794 | int *oplenp, int *argsp) |
| 795 | { |
| 796 | int oplen = 1; |
| 797 | int args = 0; |
| 798 | enum f90_range_type range_type; |
| 799 | int i; |
| 800 | |
| 801 | if (endpos < 1) |
| 802 | error (_("?error in operator_length_standard")); |
| 803 | |
| 804 | i = (int) expr->elts[endpos - 1].opcode; |
| 805 | |
| 806 | switch (i) |
| 807 | { |
| 808 | /* C++ */ |
| 809 | case OP_SCOPE: |
| 810 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 811 | oplen = 5 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 812 | break; |
| 813 | |
| 814 | case OP_LONG: |
| 815 | case OP_DOUBLE: |
| 816 | case OP_DECFLOAT: |
| 817 | case OP_VAR_VALUE: |
| 818 | oplen = 4; |
| 819 | break; |
| 820 | |
| 821 | case OP_TYPE: |
| 822 | case OP_BOOL: |
| 823 | case OP_LAST: |
| 824 | case OP_INTERNALVAR: |
| 825 | oplen = 3; |
| 826 | break; |
| 827 | |
| 828 | case OP_COMPLEX: |
| 829 | oplen = 3; |
| 830 | args = 2; |
| 831 | break; |
| 832 | |
| 833 | case OP_FUNCALL: |
| 834 | case OP_F77_UNDETERMINED_ARGLIST: |
| 835 | oplen = 3; |
| 836 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 837 | break; |
| 838 | |
| 839 | case TYPE_INSTANCE: |
| 840 | oplen = 4 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 841 | args = 1; |
| 842 | break; |
| 843 | |
| 844 | case OP_OBJC_MSGCALL: /* Objective C message (method) call */ |
| 845 | oplen = 4; |
| 846 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 847 | break; |
| 848 | |
| 849 | case UNOP_MAX: |
| 850 | case UNOP_MIN: |
| 851 | oplen = 3; |
| 852 | break; |
| 853 | |
| 854 | case BINOP_VAL: |
| 855 | case UNOP_CAST: |
| 856 | case UNOP_DYNAMIC_CAST: |
| 857 | case UNOP_REINTERPRET_CAST: |
| 858 | case UNOP_MEMVAL: |
| 859 | oplen = 3; |
| 860 | args = 1; |
| 861 | break; |
| 862 | |
| 863 | case UNOP_MEMVAL_TLS: |
| 864 | oplen = 4; |
| 865 | args = 1; |
| 866 | break; |
| 867 | |
| 868 | case UNOP_ABS: |
| 869 | case UNOP_CAP: |
| 870 | case UNOP_CHR: |
| 871 | case UNOP_FLOAT: |
| 872 | case UNOP_HIGH: |
| 873 | case UNOP_ODD: |
| 874 | case UNOP_ORD: |
| 875 | case UNOP_TRUNC: |
| 876 | oplen = 1; |
| 877 | args = 1; |
| 878 | break; |
| 879 | |
| 880 | case OP_LABELED: |
| 881 | case STRUCTOP_STRUCT: |
| 882 | case STRUCTOP_PTR: |
| 883 | args = 1; |
| 884 | /* fall through */ |
| 885 | case OP_REGISTER: |
| 886 | case OP_M2_STRING: |
| 887 | case OP_STRING: |
| 888 | case OP_OBJC_NSSTRING: /* Objective C Foundation Class NSString constant */ |
| 889 | case OP_OBJC_SELECTOR: /* Objective C "@selector" pseudo-op */ |
| 890 | case OP_NAME: |
| 891 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 892 | oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1); |
| 893 | break; |
| 894 | |
| 895 | case OP_BITSTRING: |
| 896 | oplen = longest_to_int (expr->elts[endpos - 2].longconst); |
| 897 | oplen = (oplen + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT; |
| 898 | oplen = 4 + BYTES_TO_EXP_ELEM (oplen); |
| 899 | break; |
| 900 | |
| 901 | case OP_ARRAY: |
| 902 | oplen = 4; |
| 903 | args = longest_to_int (expr->elts[endpos - 2].longconst); |
| 904 | args -= longest_to_int (expr->elts[endpos - 3].longconst); |
| 905 | args += 1; |
| 906 | break; |
| 907 | |
| 908 | case TERNOP_COND: |
| 909 | case TERNOP_SLICE: |
| 910 | case TERNOP_SLICE_COUNT: |
| 911 | args = 3; |
| 912 | break; |
| 913 | |
| 914 | /* Modula-2 */ |
| 915 | case MULTI_SUBSCRIPT: |
| 916 | oplen = 3; |
| 917 | args = 1 + longest_to_int (expr->elts[endpos - 2].longconst); |
| 918 | break; |
| 919 | |
| 920 | case BINOP_ASSIGN_MODIFY: |
| 921 | oplen = 3; |
| 922 | args = 2; |
| 923 | break; |
| 924 | |
| 925 | /* C++ */ |
| 926 | case OP_THIS: |
| 927 | case OP_OBJC_SELF: |
| 928 | oplen = 2; |
| 929 | break; |
| 930 | |
| 931 | case OP_F90_RANGE: |
| 932 | oplen = 3; |
| 933 | |
| 934 | range_type = longest_to_int (expr->elts[endpos - 2].longconst); |
| 935 | switch (range_type) |
| 936 | { |
| 937 | case LOW_BOUND_DEFAULT: |
| 938 | case HIGH_BOUND_DEFAULT: |
| 939 | args = 1; |
| 940 | break; |
| 941 | case BOTH_BOUND_DEFAULT: |
| 942 | args = 0; |
| 943 | break; |
| 944 | case NONE_BOUND_DEFAULT: |
| 945 | args = 2; |
| 946 | break; |
| 947 | } |
| 948 | |
| 949 | break; |
| 950 | |
| 951 | default: |
| 952 | args = 1 + (i < (int) BINOP_END); |
| 953 | } |
| 954 | |
| 955 | *oplenp = oplen; |
| 956 | *argsp = args; |
| 957 | } |
| 958 | |
| 959 | /* Copy the subexpression ending just before index INEND in INEXPR |
| 960 | into OUTEXPR, starting at index OUTBEG. |
| 961 | In the process, convert it from suffix to prefix form. |
| 962 | If EXPOUT_LAST_STRUCT is -1, then this function always returns -1. |
| 963 | Otherwise, it returns the index of the subexpression which is the |
| 964 | left-hand-side of the expression at EXPOUT_LAST_STRUCT. */ |
| 965 | |
| 966 | static int |
| 967 | prefixify_subexp (struct expression *inexpr, |
| 968 | struct expression *outexpr, int inend, int outbeg) |
| 969 | { |
| 970 | int oplen; |
| 971 | int args; |
| 972 | int i; |
| 973 | int *arglens; |
| 974 | enum exp_opcode opcode; |
| 975 | int result = -1; |
| 976 | |
| 977 | operator_length (inexpr, inend, &oplen, &args); |
| 978 | |
| 979 | /* Copy the final operator itself, from the end of the input |
| 980 | to the beginning of the output. */ |
| 981 | inend -= oplen; |
| 982 | memcpy (&outexpr->elts[outbeg], &inexpr->elts[inend], |
| 983 | EXP_ELEM_TO_BYTES (oplen)); |
| 984 | outbeg += oplen; |
| 985 | |
| 986 | if (expout_last_struct == inend) |
| 987 | result = outbeg - oplen; |
| 988 | |
| 989 | /* Find the lengths of the arg subexpressions. */ |
| 990 | arglens = (int *) alloca (args * sizeof (int)); |
| 991 | for (i = args - 1; i >= 0; i--) |
| 992 | { |
| 993 | oplen = length_of_subexp (inexpr, inend); |
| 994 | arglens[i] = oplen; |
| 995 | inend -= oplen; |
| 996 | } |
| 997 | |
| 998 | /* Now copy each subexpression, preserving the order of |
| 999 | the subexpressions, but prefixifying each one. |
| 1000 | In this loop, inend starts at the beginning of |
| 1001 | the expression this level is working on |
| 1002 | and marches forward over the arguments. |
| 1003 | outbeg does similarly in the output. */ |
| 1004 | for (i = 0; i < args; i++) |
| 1005 | { |
| 1006 | int r; |
| 1007 | oplen = arglens[i]; |
| 1008 | inend += oplen; |
| 1009 | r = prefixify_subexp (inexpr, outexpr, inend, outbeg); |
| 1010 | if (r != -1) |
| 1011 | { |
| 1012 | /* Return immediately. We probably have only parsed a |
| 1013 | partial expression, so we don't want to try to reverse |
| 1014 | the other operands. */ |
| 1015 | return r; |
| 1016 | } |
| 1017 | outbeg += oplen; |
| 1018 | } |
| 1019 | |
| 1020 | return result; |
| 1021 | } |
| 1022 | \f |
| 1023 | /* This page contains the two entry points to this file. */ |
| 1024 | |
| 1025 | /* Read an expression from the string *STRINGPTR points to, |
| 1026 | parse it, and return a pointer to a struct expression that we malloc. |
| 1027 | Use block BLOCK as the lexical context for variable names; |
| 1028 | if BLOCK is zero, use the block of the selected stack frame. |
| 1029 | Meanwhile, advance *STRINGPTR to point after the expression, |
| 1030 | at the first nonwhite character that is not part of the expression |
| 1031 | (possibly a null character). |
| 1032 | |
| 1033 | If COMMA is nonzero, stop if a comma is reached. */ |
| 1034 | |
| 1035 | struct expression * |
| 1036 | parse_exp_1 (char **stringptr, struct block *block, int comma) |
| 1037 | { |
| 1038 | return parse_exp_in_context (stringptr, block, comma, 0, NULL); |
| 1039 | } |
| 1040 | |
| 1041 | /* As for parse_exp_1, except that if VOID_CONTEXT_P, then |
| 1042 | no value is expected from the expression. |
| 1043 | OUT_SUBEXP is set when attempting to complete a field name; in this |
| 1044 | case it is set to the index of the subexpression on the |
| 1045 | left-hand-side of the struct op. If not doing such completion, it |
| 1046 | is left untouched. */ |
| 1047 | |
| 1048 | static struct expression * |
| 1049 | parse_exp_in_context (char **stringptr, struct block *block, int comma, |
| 1050 | int void_context_p, int *out_subexp) |
| 1051 | { |
| 1052 | volatile struct gdb_exception except; |
| 1053 | struct cleanup *old_chain; |
| 1054 | int subexp; |
| 1055 | |
| 1056 | lexptr = *stringptr; |
| 1057 | prev_lexptr = NULL; |
| 1058 | |
| 1059 | paren_depth = 0; |
| 1060 | type_stack_depth = 0; |
| 1061 | expout_last_struct = -1; |
| 1062 | |
| 1063 | comma_terminates = comma; |
| 1064 | |
| 1065 | if (lexptr == 0 || *lexptr == 0) |
| 1066 | error_no_arg (_("expression to compute")); |
| 1067 | |
| 1068 | old_chain = make_cleanup (free_funcalls, 0 /*ignore*/); |
| 1069 | funcall_chain = 0; |
| 1070 | |
| 1071 | expression_context_block = block; |
| 1072 | |
| 1073 | /* If no context specified, try using the current frame, if any. */ |
| 1074 | if (!expression_context_block) |
| 1075 | expression_context_block = get_selected_block (&expression_context_pc); |
| 1076 | else |
| 1077 | expression_context_pc = BLOCK_START (expression_context_block); |
| 1078 | |
| 1079 | /* Fall back to using the current source static context, if any. */ |
| 1080 | |
| 1081 | if (!expression_context_block) |
| 1082 | { |
| 1083 | struct symtab_and_line cursal = get_current_source_symtab_and_line (); |
| 1084 | if (cursal.symtab) |
| 1085 | expression_context_block |
| 1086 | = BLOCKVECTOR_BLOCK (BLOCKVECTOR (cursal.symtab), STATIC_BLOCK); |
| 1087 | if (expression_context_block) |
| 1088 | expression_context_pc = BLOCK_START (expression_context_block); |
| 1089 | } |
| 1090 | |
| 1091 | expout_size = 10; |
| 1092 | expout_ptr = 0; |
| 1093 | expout = (struct expression *) |
| 1094 | xmalloc (sizeof (struct expression) + EXP_ELEM_TO_BYTES (expout_size)); |
| 1095 | expout->language_defn = current_language; |
| 1096 | expout->gdbarch = get_current_arch (); |
| 1097 | |
| 1098 | TRY_CATCH (except, RETURN_MASK_ALL) |
| 1099 | { |
| 1100 | if (current_language->la_parser ()) |
| 1101 | current_language->la_error (NULL); |
| 1102 | } |
| 1103 | if (except.reason < 0) |
| 1104 | { |
| 1105 | if (! in_parse_field) |
| 1106 | { |
| 1107 | xfree (expout); |
| 1108 | throw_exception (except); |
| 1109 | } |
| 1110 | } |
| 1111 | |
| 1112 | discard_cleanups (old_chain); |
| 1113 | |
| 1114 | /* Record the actual number of expression elements, and then |
| 1115 | reallocate the expression memory so that we free up any |
| 1116 | excess elements. */ |
| 1117 | |
| 1118 | expout->nelts = expout_ptr; |
| 1119 | expout = (struct expression *) |
| 1120 | xrealloc ((char *) expout, |
| 1121 | sizeof (struct expression) + EXP_ELEM_TO_BYTES (expout_ptr));; |
| 1122 | |
| 1123 | /* Convert expression from postfix form as generated by yacc |
| 1124 | parser, to a prefix form. */ |
| 1125 | |
| 1126 | if (expressiondebug) |
| 1127 | dump_raw_expression (expout, gdb_stdlog, |
| 1128 | "before conversion to prefix form"); |
| 1129 | |
| 1130 | subexp = prefixify_expression (expout); |
| 1131 | if (out_subexp) |
| 1132 | *out_subexp = subexp; |
| 1133 | |
| 1134 | current_language->la_post_parser (&expout, void_context_p); |
| 1135 | |
| 1136 | if (expressiondebug) |
| 1137 | dump_prefix_expression (expout, gdb_stdlog); |
| 1138 | |
| 1139 | *stringptr = lexptr; |
| 1140 | return expout; |
| 1141 | } |
| 1142 | |
| 1143 | /* Parse STRING as an expression, and complain if this fails |
| 1144 | to use up all of the contents of STRING. */ |
| 1145 | |
| 1146 | struct expression * |
| 1147 | parse_expression (char *string) |
| 1148 | { |
| 1149 | struct expression *exp; |
| 1150 | exp = parse_exp_1 (&string, 0, 0); |
| 1151 | if (*string) |
| 1152 | error (_("Junk after end of expression.")); |
| 1153 | return exp; |
| 1154 | } |
| 1155 | |
| 1156 | /* Parse STRING as an expression. If parsing ends in the middle of a |
| 1157 | field reference, return the type of the left-hand-side of the |
| 1158 | reference; furthermore, if the parsing ends in the field name, |
| 1159 | return the field name in *NAME. In all other cases, return NULL. |
| 1160 | Returned non-NULL *NAME must be freed by the caller. */ |
| 1161 | |
| 1162 | struct type * |
| 1163 | parse_field_expression (char *string, char **name) |
| 1164 | { |
| 1165 | struct expression *exp = NULL; |
| 1166 | struct value *val; |
| 1167 | int subexp; |
| 1168 | volatile struct gdb_exception except; |
| 1169 | |
| 1170 | TRY_CATCH (except, RETURN_MASK_ALL) |
| 1171 | { |
| 1172 | in_parse_field = 1; |
| 1173 | exp = parse_exp_in_context (&string, 0, 0, 0, &subexp); |
| 1174 | } |
| 1175 | in_parse_field = 0; |
| 1176 | if (except.reason < 0 || ! exp) |
| 1177 | return NULL; |
| 1178 | if (expout_last_struct == -1) |
| 1179 | { |
| 1180 | xfree (exp); |
| 1181 | return NULL; |
| 1182 | } |
| 1183 | |
| 1184 | *name = extract_field_op (exp, &subexp); |
| 1185 | if (!*name) |
| 1186 | { |
| 1187 | xfree (exp); |
| 1188 | return NULL; |
| 1189 | } |
| 1190 | /* (*NAME) is a part of the EXP memory block freed below. */ |
| 1191 | *name = xstrdup (*name); |
| 1192 | |
| 1193 | val = evaluate_subexpression_type (exp, subexp); |
| 1194 | xfree (exp); |
| 1195 | |
| 1196 | return value_type (val); |
| 1197 | } |
| 1198 | |
| 1199 | /* A post-parser that does nothing */ |
| 1200 | |
| 1201 | void |
| 1202 | null_post_parser (struct expression **exp, int void_context_p) |
| 1203 | { |
| 1204 | } |
| 1205 | \f |
| 1206 | /* Stuff for maintaining a stack of types. Currently just used by C, but |
| 1207 | probably useful for any language which declares its types "backwards". */ |
| 1208 | |
| 1209 | static void |
| 1210 | check_type_stack_depth (void) |
| 1211 | { |
| 1212 | if (type_stack_depth == type_stack_size) |
| 1213 | { |
| 1214 | type_stack_size *= 2; |
| 1215 | type_stack = (union type_stack_elt *) |
| 1216 | xrealloc ((char *) type_stack, type_stack_size * sizeof (*type_stack)); |
| 1217 | } |
| 1218 | } |
| 1219 | |
| 1220 | void |
| 1221 | push_type (enum type_pieces tp) |
| 1222 | { |
| 1223 | check_type_stack_depth (); |
| 1224 | type_stack[type_stack_depth++].piece = tp; |
| 1225 | } |
| 1226 | |
| 1227 | void |
| 1228 | push_type_int (int n) |
| 1229 | { |
| 1230 | check_type_stack_depth (); |
| 1231 | type_stack[type_stack_depth++].int_val = n; |
| 1232 | } |
| 1233 | |
| 1234 | void |
| 1235 | push_type_address_space (char *string) |
| 1236 | { |
| 1237 | push_type_int (address_space_name_to_int (parse_gdbarch, string)); |
| 1238 | } |
| 1239 | |
| 1240 | enum type_pieces |
| 1241 | pop_type (void) |
| 1242 | { |
| 1243 | if (type_stack_depth) |
| 1244 | return type_stack[--type_stack_depth].piece; |
| 1245 | return tp_end; |
| 1246 | } |
| 1247 | |
| 1248 | int |
| 1249 | pop_type_int (void) |
| 1250 | { |
| 1251 | if (type_stack_depth) |
| 1252 | return type_stack[--type_stack_depth].int_val; |
| 1253 | /* "Can't happen". */ |
| 1254 | return 0; |
| 1255 | } |
| 1256 | |
| 1257 | /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE |
| 1258 | as modified by all the stuff on the stack. */ |
| 1259 | struct type * |
| 1260 | follow_types (struct type *follow_type) |
| 1261 | { |
| 1262 | int done = 0; |
| 1263 | int make_const = 0; |
| 1264 | int make_volatile = 0; |
| 1265 | int make_addr_space = 0; |
| 1266 | int array_size; |
| 1267 | |
| 1268 | while (!done) |
| 1269 | switch (pop_type ()) |
| 1270 | { |
| 1271 | case tp_end: |
| 1272 | done = 1; |
| 1273 | if (make_const) |
| 1274 | follow_type = make_cv_type (make_const, |
| 1275 | TYPE_VOLATILE (follow_type), |
| 1276 | follow_type, 0); |
| 1277 | if (make_volatile) |
| 1278 | follow_type = make_cv_type (TYPE_CONST (follow_type), |
| 1279 | make_volatile, |
| 1280 | follow_type, 0); |
| 1281 | if (make_addr_space) |
| 1282 | follow_type = make_type_with_address_space (follow_type, |
| 1283 | make_addr_space); |
| 1284 | make_const = make_volatile = 0; |
| 1285 | make_addr_space = 0; |
| 1286 | break; |
| 1287 | case tp_const: |
| 1288 | make_const = 1; |
| 1289 | break; |
| 1290 | case tp_volatile: |
| 1291 | make_volatile = 1; |
| 1292 | break; |
| 1293 | case tp_space_identifier: |
| 1294 | make_addr_space = pop_type_int (); |
| 1295 | break; |
| 1296 | case tp_pointer: |
| 1297 | follow_type = lookup_pointer_type (follow_type); |
| 1298 | if (make_const) |
| 1299 | follow_type = make_cv_type (make_const, |
| 1300 | TYPE_VOLATILE (follow_type), |
| 1301 | follow_type, 0); |
| 1302 | if (make_volatile) |
| 1303 | follow_type = make_cv_type (TYPE_CONST (follow_type), |
| 1304 | make_volatile, |
| 1305 | follow_type, 0); |
| 1306 | if (make_addr_space) |
| 1307 | follow_type = make_type_with_address_space (follow_type, |
| 1308 | make_addr_space); |
| 1309 | make_const = make_volatile = 0; |
| 1310 | make_addr_space = 0; |
| 1311 | break; |
| 1312 | case tp_reference: |
| 1313 | follow_type = lookup_reference_type (follow_type); |
| 1314 | if (make_const) |
| 1315 | follow_type = make_cv_type (make_const, |
| 1316 | TYPE_VOLATILE (follow_type), |
| 1317 | follow_type, 0); |
| 1318 | if (make_volatile) |
| 1319 | follow_type = make_cv_type (TYPE_CONST (follow_type), |
| 1320 | make_volatile, |
| 1321 | follow_type, 0); |
| 1322 | if (make_addr_space) |
| 1323 | follow_type = make_type_with_address_space (follow_type, |
| 1324 | make_addr_space); |
| 1325 | make_const = make_volatile = 0; |
| 1326 | make_addr_space = 0; |
| 1327 | break; |
| 1328 | case tp_array: |
| 1329 | array_size = pop_type_int (); |
| 1330 | /* FIXME-type-allocation: need a way to free this type when we are |
| 1331 | done with it. */ |
| 1332 | follow_type = |
| 1333 | lookup_array_range_type (follow_type, |
| 1334 | 0, array_size >= 0 ? array_size - 1 : 0); |
| 1335 | if (array_size < 0) |
| 1336 | TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (follow_type) = 1; |
| 1337 | break; |
| 1338 | case tp_function: |
| 1339 | /* FIXME-type-allocation: need a way to free this type when we are |
| 1340 | done with it. */ |
| 1341 | follow_type = lookup_function_type (follow_type); |
| 1342 | break; |
| 1343 | } |
| 1344 | return follow_type; |
| 1345 | } |
| 1346 | \f |
| 1347 | /* This function avoids direct calls to fprintf |
| 1348 | in the parser generated debug code. */ |
| 1349 | void |
| 1350 | parser_fprintf (FILE *x, const char *y, ...) |
| 1351 | { |
| 1352 | va_list args; |
| 1353 | va_start (args, y); |
| 1354 | if (x == stderr) |
| 1355 | vfprintf_unfiltered (gdb_stderr, y, args); |
| 1356 | else |
| 1357 | { |
| 1358 | fprintf_unfiltered (gdb_stderr, " Unknown FILE used.\n"); |
| 1359 | vfprintf_unfiltered (gdb_stderr, y, args); |
| 1360 | } |
| 1361 | va_end (args); |
| 1362 | } |
| 1363 | |
| 1364 | void |
| 1365 | _initialize_parse (void) |
| 1366 | { |
| 1367 | type_stack_size = 80; |
| 1368 | type_stack_depth = 0; |
| 1369 | type_stack = (union type_stack_elt *) |
| 1370 | xmalloc (type_stack_size * sizeof (*type_stack)); |
| 1371 | |
| 1372 | add_setshow_zinteger_cmd ("expression", class_maintenance, |
| 1373 | &expressiondebug, _("\ |
| 1374 | Set expression debugging."), _("\ |
| 1375 | Show expression debugging."), _("\ |
| 1376 | When non-zero, the internal representation of expressions will be printed."), |
| 1377 | NULL, |
| 1378 | show_expressiondebug, |
| 1379 | &setdebuglist, &showdebuglist); |
| 1380 | } |