| 1 | /* Evaluate expressions for GDB. |
| 2 | Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "symtab.h" |
| 22 | #include "gdbtypes.h" |
| 23 | #include "value.h" |
| 24 | #include "expression.h" |
| 25 | #include "target.h" |
| 26 | #include "frame.h" |
| 27 | #include "demangle.h" |
| 28 | #include "language.h" /* For CAST_IS_CONVERSION */ |
| 29 | |
| 30 | /* Values of NOSIDE argument to eval_subexp. */ |
| 31 | enum noside |
| 32 | { EVAL_NORMAL, |
| 33 | EVAL_SKIP, /* Only effect is to increment pos. */ |
| 34 | EVAL_AVOID_SIDE_EFFECTS /* Don't modify any variables or |
| 35 | call any functions. The value |
| 36 | returned will have the correct |
| 37 | type, and will have an |
| 38 | approximately correct lvalue |
| 39 | type (inaccuracy: anything that is |
| 40 | listed as being in a register in |
| 41 | the function in which it was |
| 42 | declared will be lval_register). */ |
| 43 | }; |
| 44 | |
| 45 | /* Prototypes for local functions. */ |
| 46 | |
| 47 | static value |
| 48 | evaluate_subexp_for_sizeof PARAMS ((struct expression *, int *)); |
| 49 | |
| 50 | static value |
| 51 | evaluate_subexp_with_coercion PARAMS ((struct expression *, int *, |
| 52 | enum noside)); |
| 53 | |
| 54 | static value |
| 55 | evaluate_subexp_for_address PARAMS ((struct expression *, int *, |
| 56 | enum noside)); |
| 57 | |
| 58 | static value |
| 59 | evaluate_subexp PARAMS ((struct type *, struct expression *, int *, |
| 60 | enum noside)); |
| 61 | |
| 62 | \f |
| 63 | /* Parse the string EXP as a C expression, evaluate it, |
| 64 | and return the result as a number. */ |
| 65 | |
| 66 | CORE_ADDR |
| 67 | parse_and_eval_address (exp) |
| 68 | char *exp; |
| 69 | { |
| 70 | struct expression *expr = parse_expression (exp); |
| 71 | register CORE_ADDR addr; |
| 72 | register struct cleanup *old_chain = |
| 73 | make_cleanup (free_current_contents, &expr); |
| 74 | |
| 75 | addr = value_as_pointer (evaluate_expression (expr)); |
| 76 | do_cleanups (old_chain); |
| 77 | return addr; |
| 78 | } |
| 79 | |
| 80 | /* Like parse_and_eval_address but takes a pointer to a char * variable |
| 81 | and advanced that variable across the characters parsed. */ |
| 82 | |
| 83 | CORE_ADDR |
| 84 | parse_and_eval_address_1 (expptr) |
| 85 | char **expptr; |
| 86 | { |
| 87 | struct expression *expr = parse_exp_1 (expptr, (struct block *)0, 0); |
| 88 | register CORE_ADDR addr; |
| 89 | register struct cleanup *old_chain = |
| 90 | make_cleanup (free_current_contents, &expr); |
| 91 | |
| 92 | addr = value_as_pointer (evaluate_expression (expr)); |
| 93 | do_cleanups (old_chain); |
| 94 | return addr; |
| 95 | } |
| 96 | |
| 97 | value |
| 98 | parse_and_eval (exp) |
| 99 | char *exp; |
| 100 | { |
| 101 | struct expression *expr = parse_expression (exp); |
| 102 | register value val; |
| 103 | register struct cleanup *old_chain |
| 104 | = make_cleanup (free_current_contents, &expr); |
| 105 | |
| 106 | val = evaluate_expression (expr); |
| 107 | do_cleanups (old_chain); |
| 108 | return val; |
| 109 | } |
| 110 | |
| 111 | /* Parse up to a comma (or to a closeparen) |
| 112 | in the string EXPP as an expression, evaluate it, and return the value. |
| 113 | EXPP is advanced to point to the comma. */ |
| 114 | |
| 115 | value |
| 116 | parse_to_comma_and_eval (expp) |
| 117 | char **expp; |
| 118 | { |
| 119 | struct expression *expr = parse_exp_1 (expp, (struct block *) 0, 1); |
| 120 | register value val; |
| 121 | register struct cleanup *old_chain |
| 122 | = make_cleanup (free_current_contents, &expr); |
| 123 | |
| 124 | val = evaluate_expression (expr); |
| 125 | do_cleanups (old_chain); |
| 126 | return val; |
| 127 | } |
| 128 | \f |
| 129 | /* Evaluate an expression in internal prefix form |
| 130 | such as is constructed by parse.y. |
| 131 | |
| 132 | See expression.h for info on the format of an expression. */ |
| 133 | |
| 134 | static value evaluate_subexp (); |
| 135 | static value evaluate_subexp_for_address (); |
| 136 | static value evaluate_subexp_for_sizeof (); |
| 137 | static value evaluate_subexp_with_coercion (); |
| 138 | |
| 139 | value |
| 140 | evaluate_expression (exp) |
| 141 | struct expression *exp; |
| 142 | { |
| 143 | int pc = 0; |
| 144 | return evaluate_subexp (NULL_TYPE, exp, &pc, EVAL_NORMAL); |
| 145 | } |
| 146 | |
| 147 | /* Evaluate an expression, avoiding all memory references |
| 148 | and getting a value whose type alone is correct. */ |
| 149 | |
| 150 | value |
| 151 | evaluate_type (exp) |
| 152 | struct expression *exp; |
| 153 | { |
| 154 | int pc = 0; |
| 155 | return evaluate_subexp (NULL_TYPE, exp, &pc, EVAL_AVOID_SIDE_EFFECTS); |
| 156 | } |
| 157 | |
| 158 | static value |
| 159 | evaluate_subexp (expect_type, exp, pos, noside) |
| 160 | struct type *expect_type; |
| 161 | register struct expression *exp; |
| 162 | register int *pos; |
| 163 | enum noside noside; |
| 164 | { |
| 165 | enum exp_opcode op; |
| 166 | int tem, tem2, tem3; |
| 167 | register int pc, pc2 = 0, oldpos; |
| 168 | register value arg1 = NULL, arg2 = NULL, arg3; |
| 169 | struct type *type; |
| 170 | int nargs; |
| 171 | value *argvec; |
| 172 | |
| 173 | pc = (*pos)++; |
| 174 | op = exp->elts[pc].opcode; |
| 175 | |
| 176 | switch (op) |
| 177 | { |
| 178 | case OP_SCOPE: |
| 179 | tem = longest_to_int (exp->elts[pc + 2].longconst); |
| 180 | (*pos) += 4 + BYTES_TO_EXP_ELEM (tem + 1); |
| 181 | arg1 = value_struct_elt_for_reference (exp->elts[pc + 1].type, |
| 182 | 0, |
| 183 | exp->elts[pc + 1].type, |
| 184 | &exp->elts[pc + 3].string, |
| 185 | expect_type); |
| 186 | if (arg1 == NULL) |
| 187 | error ("There is no field named %s", &exp->elts[pc + 3].string); |
| 188 | return arg1; |
| 189 | |
| 190 | case OP_LONG: |
| 191 | (*pos) += 3; |
| 192 | return value_from_longest (exp->elts[pc + 1].type, |
| 193 | exp->elts[pc + 2].longconst); |
| 194 | |
| 195 | case OP_DOUBLE: |
| 196 | (*pos) += 3; |
| 197 | return value_from_double (exp->elts[pc + 1].type, |
| 198 | exp->elts[pc + 2].doubleconst); |
| 199 | |
| 200 | case OP_VAR_VALUE: |
| 201 | (*pos) += 3; |
| 202 | if (noside == EVAL_SKIP) |
| 203 | goto nosideret; |
| 204 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 205 | { |
| 206 | struct symbol * sym = exp->elts[pc + 2].symbol; |
| 207 | enum lval_type lv; |
| 208 | |
| 209 | switch (SYMBOL_CLASS (sym)) |
| 210 | { |
| 211 | case LOC_CONST: |
| 212 | case LOC_LABEL: |
| 213 | case LOC_CONST_BYTES: |
| 214 | lv = not_lval; |
| 215 | break; |
| 216 | |
| 217 | case LOC_REGISTER: |
| 218 | case LOC_REGPARM: |
| 219 | lv = lval_register; |
| 220 | break; |
| 221 | |
| 222 | default: |
| 223 | lv = lval_memory; |
| 224 | break; |
| 225 | } |
| 226 | |
| 227 | return value_zero (SYMBOL_TYPE (sym), lv); |
| 228 | } |
| 229 | else |
| 230 | return value_of_variable (exp->elts[pc + 2].symbol, |
| 231 | exp->elts[pc + 1].block); |
| 232 | |
| 233 | case OP_LAST: |
| 234 | (*pos) += 2; |
| 235 | return |
| 236 | access_value_history (longest_to_int (exp->elts[pc + 1].longconst)); |
| 237 | |
| 238 | case OP_REGISTER: |
| 239 | (*pos) += 2; |
| 240 | return value_of_register (longest_to_int (exp->elts[pc + 1].longconst)); |
| 241 | |
| 242 | case OP_BOOL: |
| 243 | (*pos) += 2; |
| 244 | return value_from_longest (builtin_type_chill_bool, |
| 245 | exp->elts[pc + 1].longconst); |
| 246 | |
| 247 | case OP_INTERNALVAR: |
| 248 | (*pos) += 2; |
| 249 | return value_of_internalvar (exp->elts[pc + 1].internalvar); |
| 250 | |
| 251 | case OP_STRING: |
| 252 | tem = longest_to_int (exp->elts[pc + 1].longconst); |
| 253 | (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1); |
| 254 | if (noside == EVAL_SKIP) |
| 255 | goto nosideret; |
| 256 | return value_string (&exp->elts[pc + 2].string, tem); |
| 257 | |
| 258 | case OP_BITSTRING: |
| 259 | error ("support for OP_BITSTRING unimplemented"); |
| 260 | break; |
| 261 | |
| 262 | case OP_ARRAY: |
| 263 | (*pos) += 3; |
| 264 | tem2 = longest_to_int (exp->elts[pc + 1].longconst); |
| 265 | tem3 = longest_to_int (exp->elts[pc + 2].longconst); |
| 266 | nargs = tem3 - tem2 + 1; |
| 267 | argvec = (value *) alloca (sizeof (value) * nargs); |
| 268 | for (tem = 0; tem < nargs; tem++) |
| 269 | { |
| 270 | /* Ensure that array expressions are coerced into pointer objects. */ |
| 271 | argvec[tem] = evaluate_subexp_with_coercion (exp, pos, noside); |
| 272 | } |
| 273 | if (noside == EVAL_SKIP) |
| 274 | goto nosideret; |
| 275 | return (value_array (tem2, tem3, argvec)); |
| 276 | break; |
| 277 | |
| 278 | case TERNOP_COND: |
| 279 | /* Skip third and second args to evaluate the first one. */ |
| 280 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 281 | if (value_logical_not (arg1)) |
| 282 | { |
| 283 | evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP); |
| 284 | return evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 285 | } |
| 286 | else |
| 287 | { |
| 288 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 289 | evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP); |
| 290 | return arg2; |
| 291 | } |
| 292 | |
| 293 | case OP_FUNCALL: |
| 294 | (*pos) += 2; |
| 295 | op = exp->elts[*pos].opcode; |
| 296 | if (op == STRUCTOP_MEMBER || op == STRUCTOP_MPTR) |
| 297 | { |
| 298 | int fnptr; |
| 299 | |
| 300 | nargs = longest_to_int (exp->elts[pc + 1].longconst) + 1; |
| 301 | /* First, evaluate the structure into arg2 */ |
| 302 | pc2 = (*pos)++; |
| 303 | |
| 304 | if (noside == EVAL_SKIP) |
| 305 | goto nosideret; |
| 306 | |
| 307 | if (op == STRUCTOP_MEMBER) |
| 308 | { |
| 309 | arg2 = evaluate_subexp_for_address (exp, pos, noside); |
| 310 | } |
| 311 | else |
| 312 | { |
| 313 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 314 | } |
| 315 | |
| 316 | /* If the function is a virtual function, then the |
| 317 | aggregate value (providing the structure) plays |
| 318 | its part by providing the vtable. Otherwise, |
| 319 | it is just along for the ride: call the function |
| 320 | directly. */ |
| 321 | |
| 322 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 323 | |
| 324 | fnptr = longest_to_int (value_as_long (arg1)); |
| 325 | |
| 326 | if (METHOD_PTR_IS_VIRTUAL(fnptr)) |
| 327 | { |
| 328 | int fnoffset = METHOD_PTR_TO_VOFFSET(fnptr); |
| 329 | struct type *basetype; |
| 330 | struct type *domain_type = |
| 331 | TYPE_DOMAIN_TYPE (TYPE_TARGET_TYPE (VALUE_TYPE (arg1))); |
| 332 | int i, j; |
| 333 | basetype = TYPE_TARGET_TYPE (VALUE_TYPE (arg2)); |
| 334 | if (domain_type != basetype) |
| 335 | arg2 = value_cast(lookup_pointer_type (domain_type), arg2); |
| 336 | basetype = TYPE_VPTR_BASETYPE (domain_type); |
| 337 | for (i = TYPE_NFN_FIELDS (basetype) - 1; i >= 0; i--) |
| 338 | { |
| 339 | struct fn_field *f = TYPE_FN_FIELDLIST1 (basetype, i); |
| 340 | /* If one is virtual, then all are virtual. */ |
| 341 | if (TYPE_FN_FIELD_VIRTUAL_P (f, 0)) |
| 342 | for (j = TYPE_FN_FIELDLIST_LENGTH (basetype, i) - 1; j >= 0; --j) |
| 343 | if (TYPE_FN_FIELD_VOFFSET (f, j) == fnoffset) |
| 344 | { |
| 345 | value temp = value_ind (arg2); |
| 346 | arg1 = value_virtual_fn_field (&temp, f, j, domain_type, 0); |
| 347 | arg2 = value_addr (temp); |
| 348 | goto got_it; |
| 349 | } |
| 350 | } |
| 351 | if (i < 0) |
| 352 | error ("virtual function at index %d not found", fnoffset); |
| 353 | } |
| 354 | else |
| 355 | { |
| 356 | VALUE_TYPE (arg1) = lookup_pointer_type (TYPE_TARGET_TYPE (VALUE_TYPE (arg1))); |
| 357 | } |
| 358 | got_it: |
| 359 | |
| 360 | /* Now, say which argument to start evaluating from */ |
| 361 | tem = 2; |
| 362 | } |
| 363 | else if (op == STRUCTOP_STRUCT || op == STRUCTOP_PTR) |
| 364 | { |
| 365 | /* Hair for method invocations */ |
| 366 | int tem2; |
| 367 | |
| 368 | nargs = longest_to_int (exp->elts[pc + 1].longconst) + 1; |
| 369 | /* First, evaluate the structure into arg2 */ |
| 370 | pc2 = (*pos)++; |
| 371 | tem2 = longest_to_int (exp->elts[pc2 + 1].longconst); |
| 372 | *pos += 3 + BYTES_TO_EXP_ELEM (tem2 + 1); |
| 373 | if (noside == EVAL_SKIP) |
| 374 | goto nosideret; |
| 375 | |
| 376 | if (op == STRUCTOP_STRUCT) |
| 377 | { |
| 378 | /* If v is a variable in a register, and the user types |
| 379 | v.method (), this will produce an error, because v has |
| 380 | no address. |
| 381 | |
| 382 | A possible way around this would be to allocate a |
| 383 | copy of the variable on the stack, copy in the |
| 384 | contents, call the function, and copy out the |
| 385 | contents. I.e. convert this from call by reference |
| 386 | to call by copy-return (or whatever it's called). |
| 387 | However, this does not work because it is not the |
| 388 | same: the method being called could stash a copy of |
| 389 | the address, and then future uses through that address |
| 390 | (after the method returns) would be expected to |
| 391 | use the variable itself, not some copy of it. */ |
| 392 | arg2 = evaluate_subexp_for_address (exp, pos, noside); |
| 393 | } |
| 394 | else |
| 395 | { |
| 396 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 397 | } |
| 398 | /* Now, say which argument to start evaluating from */ |
| 399 | tem = 2; |
| 400 | } |
| 401 | else |
| 402 | { |
| 403 | nargs = longest_to_int (exp->elts[pc + 1].longconst); |
| 404 | tem = 0; |
| 405 | } |
| 406 | /* Allocate arg vector, including space for the function to be |
| 407 | called in argvec[0] and a terminating NULL */ |
| 408 | argvec = (value *) alloca (sizeof (value) * (nargs + 2)); |
| 409 | for (; tem <= nargs; tem++) |
| 410 | /* Ensure that array expressions are coerced into pointer objects. */ |
| 411 | argvec[tem] = evaluate_subexp_with_coercion (exp, pos, noside); |
| 412 | |
| 413 | /* signal end of arglist */ |
| 414 | argvec[tem] = 0; |
| 415 | |
| 416 | if (op == STRUCTOP_STRUCT || op == STRUCTOP_PTR) |
| 417 | { |
| 418 | int static_memfuncp; |
| 419 | value temp = arg2; |
| 420 | char tstr[15], mangle_tstr[15], *ptr, *mangle_ptr; |
| 421 | char *pp; |
| 422 | |
| 423 | argvec[1] = arg2; |
| 424 | argvec[0] = 0; |
| 425 | strcpy(tstr, &exp->elts[pc2+2].string); |
| 426 | if (!strncmp(tstr, "operator", 8)) |
| 427 | { |
| 428 | ptr = &tstr[8]; |
| 429 | strcpy(mangle_tstr, "__"); |
| 430 | mangle_ptr = &mangle_tstr[2]; |
| 431 | pp = cplus_mangle_opname(ptr, DMGL_ANSI); |
| 432 | if (pp) |
| 433 | strcpy(mangle_ptr, pp); |
| 434 | else |
| 435 | strcpy(mangle_ptr, ptr); |
| 436 | argvec[0] = |
| 437 | value_struct_elt (&temp, argvec+1, mangle_tstr, |
| 438 | &static_memfuncp, |
| 439 | op == STRUCTOP_STRUCT |
| 440 | ? "structure" : "structure pointer"); |
| 441 | if (!argvec[0]) |
| 442 | { |
| 443 | pp = cplus_mangle_opname(ptr, DMGL_NO_OPTS); |
| 444 | if (pp) |
| 445 | strcpy(mangle_ptr, pp); |
| 446 | else |
| 447 | strcpy(mangle_ptr, ptr); |
| 448 | strcpy(tstr, mangle_tstr); |
| 449 | } |
| 450 | } |
| 451 | if (!argvec[0]) |
| 452 | { |
| 453 | temp = arg2; |
| 454 | argvec[0] = |
| 455 | value_struct_elt (&temp, argvec+1, tstr, |
| 456 | &static_memfuncp, |
| 457 | op == STRUCTOP_STRUCT |
| 458 | ? "structure" : "structure pointer"); |
| 459 | } |
| 460 | arg2 = value_from_longest (lookup_pointer_type(VALUE_TYPE (temp)), |
| 461 | VALUE_ADDRESS (temp)+VALUE_OFFSET (temp)); |
| 462 | argvec[1] = arg2; |
| 463 | |
| 464 | if (static_memfuncp) |
| 465 | { |
| 466 | argvec[1] = argvec[0]; |
| 467 | nargs--; |
| 468 | argvec++; |
| 469 | } |
| 470 | } |
| 471 | else if (op == STRUCTOP_MEMBER || op == STRUCTOP_MPTR) |
| 472 | { |
| 473 | argvec[1] = arg2; |
| 474 | argvec[0] = arg1; |
| 475 | } |
| 476 | |
| 477 | if (noside == EVAL_SKIP) |
| 478 | goto nosideret; |
| 479 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 480 | { |
| 481 | /* If the return type doesn't look like a function type, call an |
| 482 | error. This can happen if somebody tries to turn a variable into |
| 483 | a function call. This is here because people often want to |
| 484 | call, eg, strcmp, which gdb doesn't know is a function. If |
| 485 | gdb isn't asked for it's opinion (ie. through "whatis"), |
| 486 | it won't offer it. */ |
| 487 | |
| 488 | struct type *ftype = |
| 489 | TYPE_TARGET_TYPE (VALUE_TYPE (argvec[0])); |
| 490 | |
| 491 | if (ftype) |
| 492 | return allocate_value (TYPE_TARGET_TYPE (VALUE_TYPE (argvec[0]))); |
| 493 | else |
| 494 | error ("Expression of type other than \"Function returning ...\" used as function"); |
| 495 | } |
| 496 | return call_function_by_hand (argvec[0], nargs, argvec + 1); |
| 497 | |
| 498 | case STRUCTOP_STRUCT: |
| 499 | tem = longest_to_int (exp->elts[pc + 1].longconst); |
| 500 | (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1); |
| 501 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 502 | if (noside == EVAL_SKIP) |
| 503 | goto nosideret; |
| 504 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 505 | return value_zero (lookup_struct_elt_type (VALUE_TYPE (arg1), |
| 506 | &exp->elts[pc + 2].string, |
| 507 | 0), |
| 508 | lval_memory); |
| 509 | else |
| 510 | { |
| 511 | value temp = arg1; |
| 512 | return value_struct_elt (&temp, (value *)0, &exp->elts[pc + 2].string, |
| 513 | (int *) 0, "structure"); |
| 514 | } |
| 515 | |
| 516 | case STRUCTOP_PTR: |
| 517 | tem = longest_to_int (exp->elts[pc + 1].longconst); |
| 518 | (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1); |
| 519 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 520 | if (noside == EVAL_SKIP) |
| 521 | goto nosideret; |
| 522 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 523 | return value_zero (lookup_struct_elt_type (VALUE_TYPE (arg1), |
| 524 | &exp->elts[pc + 2].string, |
| 525 | 0), |
| 526 | lval_memory); |
| 527 | else |
| 528 | { |
| 529 | value temp = arg1; |
| 530 | return value_struct_elt (&temp, (value *)0, &exp->elts[pc + 2].string, |
| 531 | (int *) 0, "structure pointer"); |
| 532 | } |
| 533 | |
| 534 | case STRUCTOP_MEMBER: |
| 535 | arg1 = evaluate_subexp_for_address (exp, pos, noside); |
| 536 | goto handle_pointer_to_member; |
| 537 | case STRUCTOP_MPTR: |
| 538 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 539 | handle_pointer_to_member: |
| 540 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 541 | if (noside == EVAL_SKIP) |
| 542 | goto nosideret; |
| 543 | if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_PTR) |
| 544 | goto bad_pointer_to_member; |
| 545 | type = TYPE_TARGET_TYPE (VALUE_TYPE (arg2)); |
| 546 | if (TYPE_CODE (type) == TYPE_CODE_METHOD) |
| 547 | error ("not implemented: pointer-to-method in pointer-to-member construct"); |
| 548 | if (TYPE_CODE (type) != TYPE_CODE_MEMBER) |
| 549 | goto bad_pointer_to_member; |
| 550 | /* Now, convert these values to an address. */ |
| 551 | arg1 = value_cast (lookup_pointer_type (TYPE_DOMAIN_TYPE (type)), |
| 552 | arg1); |
| 553 | arg3 = value_from_longest (lookup_pointer_type (TYPE_TARGET_TYPE (type)), |
| 554 | value_as_long (arg1) + value_as_long (arg2)); |
| 555 | return value_ind (arg3); |
| 556 | bad_pointer_to_member: |
| 557 | error("non-pointer-to-member value used in pointer-to-member construct"); |
| 558 | |
| 559 | case BINOP_CONCAT: |
| 560 | arg1 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 561 | arg2 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 562 | if (noside == EVAL_SKIP) |
| 563 | goto nosideret; |
| 564 | if (binop_user_defined_p (op, arg1, arg2)) |
| 565 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 566 | else |
| 567 | return value_concat (arg1, arg2); |
| 568 | |
| 569 | case BINOP_ASSIGN: |
| 570 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 571 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 572 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 573 | return arg1; |
| 574 | if (binop_user_defined_p (op, arg1, arg2)) |
| 575 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 576 | else |
| 577 | return value_assign (arg1, arg2); |
| 578 | |
| 579 | case BINOP_ASSIGN_MODIFY: |
| 580 | (*pos) += 2; |
| 581 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 582 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 583 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 584 | return arg1; |
| 585 | op = exp->elts[pc + 1].opcode; |
| 586 | if (binop_user_defined_p (op, arg1, arg2)) |
| 587 | return value_x_binop (arg1, arg2, BINOP_ASSIGN_MODIFY, op); |
| 588 | else if (op == BINOP_ADD) |
| 589 | arg2 = value_add (arg1, arg2); |
| 590 | else if (op == BINOP_SUB) |
| 591 | arg2 = value_sub (arg1, arg2); |
| 592 | else |
| 593 | arg2 = value_binop (arg1, arg2, op); |
| 594 | return value_assign (arg1, arg2); |
| 595 | |
| 596 | case BINOP_ADD: |
| 597 | arg1 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 598 | arg2 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 599 | if (noside == EVAL_SKIP) |
| 600 | goto nosideret; |
| 601 | if (binop_user_defined_p (op, arg1, arg2)) |
| 602 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 603 | else |
| 604 | return value_add (arg1, arg2); |
| 605 | |
| 606 | case BINOP_SUB: |
| 607 | arg1 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 608 | arg2 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 609 | if (noside == EVAL_SKIP) |
| 610 | goto nosideret; |
| 611 | if (binop_user_defined_p (op, arg1, arg2)) |
| 612 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 613 | else |
| 614 | return value_sub (arg1, arg2); |
| 615 | |
| 616 | case BINOP_MUL: |
| 617 | case BINOP_DIV: |
| 618 | case BINOP_REM: |
| 619 | case BINOP_MOD: |
| 620 | case BINOP_LSH: |
| 621 | case BINOP_RSH: |
| 622 | case BINOP_BITWISE_AND: |
| 623 | case BINOP_BITWISE_IOR: |
| 624 | case BINOP_BITWISE_XOR: |
| 625 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 626 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 627 | if (noside == EVAL_SKIP) |
| 628 | goto nosideret; |
| 629 | if (binop_user_defined_p (op, arg1, arg2)) |
| 630 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 631 | else |
| 632 | if (noside == EVAL_AVOID_SIDE_EFFECTS |
| 633 | && (op == BINOP_DIV || op == BINOP_REM || op == BINOP_MOD)) |
| 634 | return value_zero (VALUE_TYPE (arg1), not_lval); |
| 635 | else |
| 636 | return value_binop (arg1, arg2, op); |
| 637 | |
| 638 | case BINOP_SUBSCRIPT: |
| 639 | arg1 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 640 | arg2 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 641 | if (noside == EVAL_SKIP) |
| 642 | goto nosideret; |
| 643 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 644 | { |
| 645 | /* If the user attempts to subscript something that has no target |
| 646 | type (like a plain int variable for example), then report this |
| 647 | as an error. */ |
| 648 | |
| 649 | type = TYPE_TARGET_TYPE (VALUE_TYPE (arg1)); |
| 650 | if (type) |
| 651 | return value_zero (type, VALUE_LVAL (arg1)); |
| 652 | else |
| 653 | error ("cannot subscript something of type `%s'", |
| 654 | TYPE_NAME (VALUE_TYPE (arg1))); |
| 655 | } |
| 656 | |
| 657 | if (binop_user_defined_p (op, arg1, arg2)) |
| 658 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 659 | else |
| 660 | return value_subscript (arg1, arg2); |
| 661 | |
| 662 | case MULTI_SUBSCRIPT: |
| 663 | (*pos) += 2; |
| 664 | nargs = longest_to_int (exp->elts[pc + 1].longconst); |
| 665 | arg1 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 666 | while (nargs-- > 0) |
| 667 | { |
| 668 | arg2 = evaluate_subexp_with_coercion (exp, pos, noside); |
| 669 | /* FIXME: EVAL_SKIP handling may not be correct. */ |
| 670 | if (noside == EVAL_SKIP) |
| 671 | { |
| 672 | if (nargs > 0) |
| 673 | { |
| 674 | continue; |
| 675 | } |
| 676 | else |
| 677 | { |
| 678 | goto nosideret; |
| 679 | } |
| 680 | } |
| 681 | /* FIXME: EVAL_AVOID_SIDE_EFFECTS handling may not be correct. */ |
| 682 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 683 | { |
| 684 | /* If the user attempts to subscript something that has no target |
| 685 | type (like a plain int variable for example), then report this |
| 686 | as an error. */ |
| 687 | |
| 688 | type = TYPE_TARGET_TYPE (VALUE_TYPE (arg1)); |
| 689 | if (type != NULL) |
| 690 | { |
| 691 | arg1 = value_zero (type, VALUE_LVAL (arg1)); |
| 692 | noside = EVAL_SKIP; |
| 693 | continue; |
| 694 | } |
| 695 | else |
| 696 | { |
| 697 | error ("cannot subscript something of type `%s'", |
| 698 | TYPE_NAME (VALUE_TYPE (arg1))); |
| 699 | } |
| 700 | } |
| 701 | |
| 702 | if (binop_user_defined_p (op, arg1, arg2)) |
| 703 | { |
| 704 | arg1 = value_x_binop (arg1, arg2, op, OP_NULL); |
| 705 | } |
| 706 | else |
| 707 | { |
| 708 | arg1 = value_subscript (arg1, arg2); |
| 709 | } |
| 710 | } |
| 711 | return (arg1); |
| 712 | |
| 713 | case BINOP_LOGICAL_AND: |
| 714 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 715 | if (noside == EVAL_SKIP) |
| 716 | { |
| 717 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 718 | goto nosideret; |
| 719 | } |
| 720 | |
| 721 | oldpos = *pos; |
| 722 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, EVAL_AVOID_SIDE_EFFECTS); |
| 723 | *pos = oldpos; |
| 724 | |
| 725 | if (binop_user_defined_p (op, arg1, arg2)) |
| 726 | { |
| 727 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 728 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 729 | } |
| 730 | else |
| 731 | { |
| 732 | tem = value_logical_not (arg1); |
| 733 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, |
| 734 | (tem ? EVAL_SKIP : noside)); |
| 735 | return value_from_longest (builtin_type_int, |
| 736 | (LONGEST) (!tem && !value_logical_not (arg2))); |
| 737 | } |
| 738 | |
| 739 | case BINOP_LOGICAL_OR: |
| 740 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 741 | if (noside == EVAL_SKIP) |
| 742 | { |
| 743 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 744 | goto nosideret; |
| 745 | } |
| 746 | |
| 747 | oldpos = *pos; |
| 748 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, EVAL_AVOID_SIDE_EFFECTS); |
| 749 | *pos = oldpos; |
| 750 | |
| 751 | if (binop_user_defined_p (op, arg1, arg2)) |
| 752 | { |
| 753 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 754 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 755 | } |
| 756 | else |
| 757 | { |
| 758 | tem = value_logical_not (arg1); |
| 759 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, |
| 760 | (!tem ? EVAL_SKIP : noside)); |
| 761 | return value_from_longest (builtin_type_int, |
| 762 | (LONGEST) (!tem || !value_logical_not (arg2))); |
| 763 | } |
| 764 | |
| 765 | case BINOP_EQUAL: |
| 766 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 767 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 768 | if (noside == EVAL_SKIP) |
| 769 | goto nosideret; |
| 770 | if (binop_user_defined_p (op, arg1, arg2)) |
| 771 | { |
| 772 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 773 | } |
| 774 | else |
| 775 | { |
| 776 | tem = value_equal (arg1, arg2); |
| 777 | return value_from_longest (builtin_type_int, (LONGEST) tem); |
| 778 | } |
| 779 | |
| 780 | case BINOP_NOTEQUAL: |
| 781 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 782 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 783 | if (noside == EVAL_SKIP) |
| 784 | goto nosideret; |
| 785 | if (binop_user_defined_p (op, arg1, arg2)) |
| 786 | { |
| 787 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 788 | } |
| 789 | else |
| 790 | { |
| 791 | tem = value_equal (arg1, arg2); |
| 792 | return value_from_longest (builtin_type_int, (LONGEST) ! tem); |
| 793 | } |
| 794 | |
| 795 | case BINOP_LESS: |
| 796 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 797 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 798 | if (noside == EVAL_SKIP) |
| 799 | goto nosideret; |
| 800 | if (binop_user_defined_p (op, arg1, arg2)) |
| 801 | { |
| 802 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 803 | } |
| 804 | else |
| 805 | { |
| 806 | tem = value_less (arg1, arg2); |
| 807 | return value_from_longest (builtin_type_int, (LONGEST) tem); |
| 808 | } |
| 809 | |
| 810 | case BINOP_GTR: |
| 811 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 812 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 813 | if (noside == EVAL_SKIP) |
| 814 | goto nosideret; |
| 815 | if (binop_user_defined_p (op, arg1, arg2)) |
| 816 | { |
| 817 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 818 | } |
| 819 | else |
| 820 | { |
| 821 | tem = value_less (arg2, arg1); |
| 822 | return value_from_longest (builtin_type_int, (LONGEST) tem); |
| 823 | } |
| 824 | |
| 825 | case BINOP_GEQ: |
| 826 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 827 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 828 | if (noside == EVAL_SKIP) |
| 829 | goto nosideret; |
| 830 | if (binop_user_defined_p (op, arg1, arg2)) |
| 831 | { |
| 832 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 833 | } |
| 834 | else |
| 835 | { |
| 836 | tem = value_less (arg2, arg1) || value_equal (arg1, arg2); |
| 837 | return value_from_longest (builtin_type_int, (LONGEST) tem); |
| 838 | } |
| 839 | |
| 840 | case BINOP_LEQ: |
| 841 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 842 | arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside); |
| 843 | if (noside == EVAL_SKIP) |
| 844 | goto nosideret; |
| 845 | if (binop_user_defined_p (op, arg1, arg2)) |
| 846 | { |
| 847 | return value_x_binop (arg1, arg2, op, OP_NULL); |
| 848 | } |
| 849 | else |
| 850 | { |
| 851 | tem = value_less (arg1, arg2) || value_equal (arg1, arg2); |
| 852 | return value_from_longest (builtin_type_int, (LONGEST) tem); |
| 853 | } |
| 854 | |
| 855 | case BINOP_REPEAT: |
| 856 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 857 | arg2 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 858 | if (noside == EVAL_SKIP) |
| 859 | goto nosideret; |
| 860 | if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_INT) |
| 861 | error ("Non-integral right operand for \"@\" operator."); |
| 862 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 863 | return allocate_repeat_value (VALUE_TYPE (arg1), |
| 864 | longest_to_int (value_as_long (arg2))); |
| 865 | else |
| 866 | return value_repeat (arg1, longest_to_int (value_as_long (arg2))); |
| 867 | |
| 868 | case BINOP_COMMA: |
| 869 | evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 870 | return evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 871 | |
| 872 | case UNOP_NEG: |
| 873 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 874 | if (noside == EVAL_SKIP) |
| 875 | goto nosideret; |
| 876 | if (unop_user_defined_p (op, arg1)) |
| 877 | return value_x_unop (arg1, op); |
| 878 | else |
| 879 | return value_neg (arg1); |
| 880 | |
| 881 | case UNOP_COMPLEMENT: |
| 882 | /* C++: check for and handle destructor names. */ |
| 883 | op = exp->elts[*pos].opcode; |
| 884 | |
| 885 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 886 | if (noside == EVAL_SKIP) |
| 887 | goto nosideret; |
| 888 | if (unop_user_defined_p (UNOP_COMPLEMENT, arg1)) |
| 889 | return value_x_unop (arg1, UNOP_COMPLEMENT); |
| 890 | else |
| 891 | return value_complement (arg1); |
| 892 | |
| 893 | case UNOP_LOGICAL_NOT: |
| 894 | arg1 = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 895 | if (noside == EVAL_SKIP) |
| 896 | goto nosideret; |
| 897 | if (unop_user_defined_p (op, arg1)) |
| 898 | return value_x_unop (arg1, op); |
| 899 | else |
| 900 | return value_from_longest (builtin_type_int, |
| 901 | (LONGEST) value_logical_not (arg1)); |
| 902 | |
| 903 | case UNOP_IND: |
| 904 | if (expect_type && TYPE_CODE (expect_type) == TYPE_CODE_PTR) |
| 905 | expect_type = TYPE_TARGET_TYPE (expect_type); |
| 906 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 907 | if (noside == EVAL_SKIP) |
| 908 | goto nosideret; |
| 909 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 910 | { |
| 911 | if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR |
| 912 | || TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_REF |
| 913 | /* In C you can dereference an array to get the 1st elt. */ |
| 914 | || TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_ARRAY |
| 915 | ) |
| 916 | return value_zero (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)), |
| 917 | lval_memory); |
| 918 | else if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_INT) |
| 919 | /* GDB allows dereferencing an int. */ |
| 920 | return value_zero (builtin_type_int, lval_memory); |
| 921 | else |
| 922 | error ("Attempt to take contents of a non-pointer value."); |
| 923 | } |
| 924 | return value_ind (arg1); |
| 925 | |
| 926 | case UNOP_ADDR: |
| 927 | /* C++: check for and handle pointer to members. */ |
| 928 | |
| 929 | op = exp->elts[*pos].opcode; |
| 930 | |
| 931 | if (noside == EVAL_SKIP) |
| 932 | { |
| 933 | if (op == OP_SCOPE) |
| 934 | { |
| 935 | int temm = longest_to_int (exp->elts[pc+3].longconst); |
| 936 | (*pos) += 3 + BYTES_TO_EXP_ELEM (temm + 1); |
| 937 | } |
| 938 | else |
| 939 | evaluate_subexp (expect_type, exp, pos, EVAL_SKIP); |
| 940 | goto nosideret; |
| 941 | } |
| 942 | |
| 943 | return evaluate_subexp_for_address (exp, pos, noside); |
| 944 | |
| 945 | case UNOP_SIZEOF: |
| 946 | if (noside == EVAL_SKIP) |
| 947 | { |
| 948 | evaluate_subexp (NULL_TYPE, exp, pos, EVAL_SKIP); |
| 949 | goto nosideret; |
| 950 | } |
| 951 | return evaluate_subexp_for_sizeof (exp, pos); |
| 952 | |
| 953 | case UNOP_CAST: |
| 954 | (*pos) += 2; |
| 955 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 956 | if (noside == EVAL_SKIP) |
| 957 | goto nosideret; |
| 958 | return value_cast (exp->elts[pc + 1].type, arg1); |
| 959 | |
| 960 | case UNOP_MEMVAL: |
| 961 | (*pos) += 2; |
| 962 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 963 | if (noside == EVAL_SKIP) |
| 964 | goto nosideret; |
| 965 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 966 | return value_zero (exp->elts[pc + 1].type, lval_memory); |
| 967 | else |
| 968 | return value_at_lazy (exp->elts[pc + 1].type, |
| 969 | value_as_pointer (arg1)); |
| 970 | |
| 971 | case UNOP_PREINCREMENT: |
| 972 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 973 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 974 | return arg1; |
| 975 | else if (unop_user_defined_p (op, arg1)) |
| 976 | { |
| 977 | return value_x_unop (arg1, op); |
| 978 | } |
| 979 | else |
| 980 | { |
| 981 | arg2 = value_add (arg1, value_from_longest (builtin_type_char, |
| 982 | (LONGEST) 1)); |
| 983 | return value_assign (arg1, arg2); |
| 984 | } |
| 985 | |
| 986 | case UNOP_PREDECREMENT: |
| 987 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 988 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 989 | return arg1; |
| 990 | else if (unop_user_defined_p (op, arg1)) |
| 991 | { |
| 992 | return value_x_unop (arg1, op); |
| 993 | } |
| 994 | else |
| 995 | { |
| 996 | arg2 = value_sub (arg1, value_from_longest (builtin_type_char, |
| 997 | (LONGEST) 1)); |
| 998 | return value_assign (arg1, arg2); |
| 999 | } |
| 1000 | |
| 1001 | case UNOP_POSTINCREMENT: |
| 1002 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 1003 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 1004 | return arg1; |
| 1005 | else if (unop_user_defined_p (op, arg1)) |
| 1006 | { |
| 1007 | return value_x_unop (arg1, op); |
| 1008 | } |
| 1009 | else |
| 1010 | { |
| 1011 | arg2 = value_add (arg1, value_from_longest (builtin_type_char, |
| 1012 | (LONGEST) 1)); |
| 1013 | value_assign (arg1, arg2); |
| 1014 | return arg1; |
| 1015 | } |
| 1016 | |
| 1017 | case UNOP_POSTDECREMENT: |
| 1018 | arg1 = evaluate_subexp (expect_type, exp, pos, noside); |
| 1019 | if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS) |
| 1020 | return arg1; |
| 1021 | else if (unop_user_defined_p (op, arg1)) |
| 1022 | { |
| 1023 | return value_x_unop (arg1, op); |
| 1024 | } |
| 1025 | else |
| 1026 | { |
| 1027 | arg2 = value_sub (arg1, value_from_longest (builtin_type_char, |
| 1028 | (LONGEST) 1)); |
| 1029 | value_assign (arg1, arg2); |
| 1030 | return arg1; |
| 1031 | } |
| 1032 | |
| 1033 | case OP_THIS: |
| 1034 | (*pos) += 1; |
| 1035 | return value_of_this (1); |
| 1036 | |
| 1037 | case OP_TYPE: |
| 1038 | error ("Attempt to use a type name as an expression"); |
| 1039 | |
| 1040 | default: |
| 1041 | /* Removing this case and compiling with gcc -Wall reveals that |
| 1042 | a lot of cases are hitting this case. Some of these should |
| 1043 | probably be removed from expression.h (e.g. do we need a BINOP_SCOPE |
| 1044 | and an OP_SCOPE?); others are legitimate expressions which are |
| 1045 | (apparently) not fully implemented. |
| 1046 | |
| 1047 | If there are any cases landing here which mean a user error, |
| 1048 | then they should be separate cases, with more descriptive |
| 1049 | error messages. */ |
| 1050 | |
| 1051 | error ("\ |
| 1052 | GDB does not (yet) know how to evaluated that kind of expression"); |
| 1053 | } |
| 1054 | |
| 1055 | nosideret: |
| 1056 | return value_from_longest (builtin_type_long, (LONGEST) 1); |
| 1057 | } |
| 1058 | \f |
| 1059 | /* Evaluate a subexpression of EXP, at index *POS, |
| 1060 | and return the address of that subexpression. |
| 1061 | Advance *POS over the subexpression. |
| 1062 | If the subexpression isn't an lvalue, get an error. |
| 1063 | NOSIDE may be EVAL_AVOID_SIDE_EFFECTS; |
| 1064 | then only the type of the result need be correct. */ |
| 1065 | |
| 1066 | static value |
| 1067 | evaluate_subexp_for_address (exp, pos, noside) |
| 1068 | register struct expression *exp; |
| 1069 | register int *pos; |
| 1070 | enum noside noside; |
| 1071 | { |
| 1072 | enum exp_opcode op; |
| 1073 | register int pc; |
| 1074 | struct symbol *var; |
| 1075 | |
| 1076 | pc = (*pos); |
| 1077 | op = exp->elts[pc].opcode; |
| 1078 | |
| 1079 | switch (op) |
| 1080 | { |
| 1081 | case UNOP_IND: |
| 1082 | (*pos)++; |
| 1083 | return evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 1084 | |
| 1085 | case UNOP_MEMVAL: |
| 1086 | (*pos) += 3; |
| 1087 | return value_cast (lookup_pointer_type (exp->elts[pc + 1].type), |
| 1088 | evaluate_subexp (NULL_TYPE, exp, pos, noside)); |
| 1089 | |
| 1090 | case OP_VAR_VALUE: |
| 1091 | var = exp->elts[pc + 2].symbol; |
| 1092 | |
| 1093 | /* C++: The "address" of a reference should yield the address |
| 1094 | * of the object pointed to. Let value_addr() deal with it. */ |
| 1095 | if (TYPE_CODE (SYMBOL_TYPE (var)) == TYPE_CODE_REF) |
| 1096 | goto default_case; |
| 1097 | |
| 1098 | (*pos) += 4; |
| 1099 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 1100 | { |
| 1101 | struct type *type = |
| 1102 | lookup_pointer_type (SYMBOL_TYPE (var)); |
| 1103 | enum address_class sym_class = SYMBOL_CLASS (var); |
| 1104 | |
| 1105 | if (sym_class == LOC_CONST |
| 1106 | || sym_class == LOC_CONST_BYTES |
| 1107 | || sym_class == LOC_REGISTER |
| 1108 | || sym_class == LOC_REGPARM) |
| 1109 | error ("Attempt to take address of register or constant."); |
| 1110 | |
| 1111 | return |
| 1112 | value_zero (type, not_lval); |
| 1113 | } |
| 1114 | else |
| 1115 | return |
| 1116 | locate_var_value |
| 1117 | (var, |
| 1118 | block_innermost_frame (exp->elts[pc + 1].block)); |
| 1119 | |
| 1120 | default: |
| 1121 | default_case: |
| 1122 | if (noside == EVAL_AVOID_SIDE_EFFECTS) |
| 1123 | { |
| 1124 | value x = evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 1125 | if (VALUE_LVAL (x) == lval_memory) |
| 1126 | return value_zero (lookup_pointer_type (VALUE_TYPE (x)), |
| 1127 | not_lval); |
| 1128 | else |
| 1129 | error ("Attempt to take address of non-lval"); |
| 1130 | } |
| 1131 | return value_addr (evaluate_subexp (NULL_TYPE, exp, pos, noside)); |
| 1132 | } |
| 1133 | } |
| 1134 | |
| 1135 | /* Evaluate like `evaluate_subexp' except coercing arrays to pointers. |
| 1136 | When used in contexts where arrays will be coerced anyway, this is |
| 1137 | equivalent to `evaluate_subexp' but much faster because it avoids |
| 1138 | actually fetching array contents (perhaps obsolete now that we have |
| 1139 | VALUE_LAZY). |
| 1140 | |
| 1141 | Note that we currently only do the coercion for C expressions, where |
| 1142 | arrays are zero based and the coercion is correct. For other languages, |
| 1143 | with nonzero based arrays, coercion loses. Use CAST_IS_CONVERSION |
| 1144 | to decide if coercion is appropriate. |
| 1145 | |
| 1146 | */ |
| 1147 | |
| 1148 | static value |
| 1149 | evaluate_subexp_with_coercion (exp, pos, noside) |
| 1150 | register struct expression *exp; |
| 1151 | register int *pos; |
| 1152 | enum noside noside; |
| 1153 | { |
| 1154 | register enum exp_opcode op; |
| 1155 | register int pc; |
| 1156 | register value val; |
| 1157 | struct symbol *var; |
| 1158 | |
| 1159 | pc = (*pos); |
| 1160 | op = exp->elts[pc].opcode; |
| 1161 | |
| 1162 | switch (op) |
| 1163 | { |
| 1164 | case OP_VAR_VALUE: |
| 1165 | var = exp->elts[pc + 2].symbol; |
| 1166 | if (TYPE_CODE (SYMBOL_TYPE (var)) == TYPE_CODE_ARRAY |
| 1167 | && CAST_IS_CONVERSION) |
| 1168 | { |
| 1169 | (*pos) += 4; |
| 1170 | val = |
| 1171 | locate_var_value |
| 1172 | (var, block_innermost_frame (exp->elts[pc + 1].block)); |
| 1173 | return value_cast (lookup_pointer_type (TYPE_TARGET_TYPE (SYMBOL_TYPE (var))), |
| 1174 | val); |
| 1175 | } |
| 1176 | /* FALLTHROUGH */ |
| 1177 | |
| 1178 | default: |
| 1179 | return evaluate_subexp (NULL_TYPE, exp, pos, noside); |
| 1180 | } |
| 1181 | } |
| 1182 | |
| 1183 | /* Evaluate a subexpression of EXP, at index *POS, |
| 1184 | and return a value for the size of that subexpression. |
| 1185 | Advance *POS over the subexpression. */ |
| 1186 | |
| 1187 | static value |
| 1188 | evaluate_subexp_for_sizeof (exp, pos) |
| 1189 | register struct expression *exp; |
| 1190 | register int *pos; |
| 1191 | { |
| 1192 | enum exp_opcode op; |
| 1193 | register int pc; |
| 1194 | value val; |
| 1195 | |
| 1196 | pc = (*pos); |
| 1197 | op = exp->elts[pc].opcode; |
| 1198 | |
| 1199 | switch (op) |
| 1200 | { |
| 1201 | /* This case is handled specially |
| 1202 | so that we avoid creating a value for the result type. |
| 1203 | If the result type is very big, it's desirable not to |
| 1204 | create a value unnecessarily. */ |
| 1205 | case UNOP_IND: |
| 1206 | (*pos)++; |
| 1207 | val = evaluate_subexp (NULL_TYPE, exp, pos, EVAL_AVOID_SIDE_EFFECTS); |
| 1208 | return value_from_longest (builtin_type_int, (LONGEST) |
| 1209 | TYPE_LENGTH (TYPE_TARGET_TYPE (VALUE_TYPE (val)))); |
| 1210 | |
| 1211 | case UNOP_MEMVAL: |
| 1212 | (*pos) += 3; |
| 1213 | return value_from_longest (builtin_type_int, |
| 1214 | (LONGEST) TYPE_LENGTH (exp->elts[pc + 1].type)); |
| 1215 | |
| 1216 | case OP_VAR_VALUE: |
| 1217 | (*pos) += 4; |
| 1218 | return |
| 1219 | value_from_longest |
| 1220 | (builtin_type_int, |
| 1221 | (LONGEST) TYPE_LENGTH (SYMBOL_TYPE (exp->elts[pc + 2].symbol))); |
| 1222 | |
| 1223 | default: |
| 1224 | val = evaluate_subexp (NULL_TYPE, exp, pos, EVAL_AVOID_SIDE_EFFECTS); |
| 1225 | return value_from_longest (builtin_type_int, |
| 1226 | (LONGEST) TYPE_LENGTH (VALUE_TYPE (val))); |
| 1227 | } |
| 1228 | } |
| 1229 | |
| 1230 | /* Parse a type expression in the string [P..P+LENGTH). */ |
| 1231 | |
| 1232 | struct type * |
| 1233 | parse_and_eval_type (p, length) |
| 1234 | char *p; |
| 1235 | int length; |
| 1236 | { |
| 1237 | char *tmp = (char *)alloca (length + 4); |
| 1238 | struct expression *expr; |
| 1239 | tmp[0] = '('; |
| 1240 | memcpy (tmp+1, p, length); |
| 1241 | tmp[length+1] = ')'; |
| 1242 | tmp[length+2] = '0'; |
| 1243 | tmp[length+3] = '\0'; |
| 1244 | expr = parse_expression (tmp); |
| 1245 | if (expr->elts[0].opcode != UNOP_CAST) |
| 1246 | error ("Internal error in eval_type."); |
| 1247 | return expr->elts[1].type; |
| 1248 | } |