| 1 | /* Parser definitions for GDB. |
| 2 | |
| 3 | Copyright (C) 1986-2021 Free Software Foundation, Inc. |
| 4 | |
| 5 | Modified from expread.y by the Department of Computer Science at the |
| 6 | State University of New York at Buffalo. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #if !defined (PARSER_DEFS_H) |
| 24 | #define PARSER_DEFS_H 1 |
| 25 | |
| 26 | #include "expression.h" |
| 27 | #include "symtab.h" |
| 28 | #include "expop.h" |
| 29 | |
| 30 | struct block; |
| 31 | struct language_defn; |
| 32 | struct internalvar; |
| 33 | class innermost_block_tracker; |
| 34 | |
| 35 | extern bool parser_debug; |
| 36 | |
| 37 | /* A class that can be used to build a "struct expression". */ |
| 38 | |
| 39 | struct expr_builder |
| 40 | { |
| 41 | /* Constructor. LANG is the language used to parse the expression. |
| 42 | And GDBARCH is the gdbarch to use during parsing. */ |
| 43 | |
| 44 | expr_builder (const struct language_defn *lang, |
| 45 | struct gdbarch *gdbarch) |
| 46 | : expout (new expression (lang, gdbarch)) |
| 47 | { |
| 48 | } |
| 49 | |
| 50 | DISABLE_COPY_AND_ASSIGN (expr_builder); |
| 51 | |
| 52 | /* Resize the allocated expression to the correct size, and return |
| 53 | it as an expression_up -- passing ownership to the caller. */ |
| 54 | ATTRIBUTE_UNUSED_RESULT expression_up release () |
| 55 | { |
| 56 | return std::move (expout); |
| 57 | } |
| 58 | |
| 59 | /* Return the gdbarch that was passed to the constructor. */ |
| 60 | |
| 61 | struct gdbarch *gdbarch () |
| 62 | { |
| 63 | return expout->gdbarch; |
| 64 | } |
| 65 | |
| 66 | /* Return the language that was passed to the constructor. */ |
| 67 | |
| 68 | const struct language_defn *language () |
| 69 | { |
| 70 | return expout->language_defn; |
| 71 | } |
| 72 | |
| 73 | /* Set the root operation of the expression that is currently being |
| 74 | built. */ |
| 75 | void set_operation (expr::operation_up &&op) |
| 76 | { |
| 77 | expout->op = std::move (op); |
| 78 | } |
| 79 | |
| 80 | /* The expression related to this parser state. */ |
| 81 | |
| 82 | expression_up expout; |
| 83 | }; |
| 84 | |
| 85 | /* This is used for expression completion. */ |
| 86 | |
| 87 | struct expr_completion_state |
| 88 | { |
| 89 | /* The last struct expression directly before a '.' or '->'. This |
| 90 | is set when parsing and is only used when completing a field |
| 91 | name. It is nullptr if no dereference operation was found. */ |
| 92 | expr::structop_base_operation *expout_last_op = nullptr; |
| 93 | |
| 94 | /* If we are completing a tagged type name, this will be nonzero. */ |
| 95 | enum type_code expout_tag_completion_type = TYPE_CODE_UNDEF; |
| 96 | |
| 97 | /* The token for tagged type name completion. */ |
| 98 | gdb::unique_xmalloc_ptr<char> expout_completion_name; |
| 99 | }; |
| 100 | |
| 101 | /* An instance of this type is instantiated during expression parsing, |
| 102 | and passed to the appropriate parser. It holds both inputs to the |
| 103 | parser, and result. */ |
| 104 | |
| 105 | struct parser_state : public expr_builder |
| 106 | { |
| 107 | /* Constructor. LANG is the language used to parse the expression. |
| 108 | And GDBARCH is the gdbarch to use during parsing. */ |
| 109 | |
| 110 | parser_state (const struct language_defn *lang, |
| 111 | struct gdbarch *gdbarch, |
| 112 | const struct block *context_block, |
| 113 | CORE_ADDR context_pc, |
| 114 | int comma, |
| 115 | const char *input, |
| 116 | bool completion, |
| 117 | innermost_block_tracker *tracker, |
| 118 | bool void_p) |
| 119 | : expr_builder (lang, gdbarch), |
| 120 | expression_context_block (context_block), |
| 121 | expression_context_pc (context_pc), |
| 122 | comma_terminates (comma), |
| 123 | lexptr (input), |
| 124 | parse_completion (completion), |
| 125 | block_tracker (tracker), |
| 126 | void_context_p (void_p) |
| 127 | { |
| 128 | } |
| 129 | |
| 130 | DISABLE_COPY_AND_ASSIGN (parser_state); |
| 131 | |
| 132 | /* Begin counting arguments for a function call, |
| 133 | saving the data about any containing call. */ |
| 134 | |
| 135 | void start_arglist () |
| 136 | { |
| 137 | m_funcall_chain.push_back (arglist_len); |
| 138 | arglist_len = 0; |
| 139 | } |
| 140 | |
| 141 | /* Return the number of arguments in a function call just terminated, |
| 142 | and restore the data for the containing function call. */ |
| 143 | |
| 144 | int end_arglist () |
| 145 | { |
| 146 | int val = arglist_len; |
| 147 | arglist_len = m_funcall_chain.back (); |
| 148 | m_funcall_chain.pop_back (); |
| 149 | return val; |
| 150 | } |
| 151 | |
| 152 | /* Mark the given operation as the starting location of a structure |
| 153 | expression. This is used when completing on field names. */ |
| 154 | |
| 155 | void mark_struct_expression (expr::structop_base_operation *op); |
| 156 | |
| 157 | /* Indicate that the current parser invocation is completing a tag. |
| 158 | TAG is the type code of the tag, and PTR and LENGTH represent the |
| 159 | start of the tag name. */ |
| 160 | |
| 161 | void mark_completion_tag (enum type_code tag, const char *ptr, int length); |
| 162 | |
| 163 | /* Push an operation on the stack. */ |
| 164 | void push (expr::operation_up &&op) |
| 165 | { |
| 166 | m_operations.push_back (std::move (op)); |
| 167 | } |
| 168 | |
| 169 | /* Create a new operation and push it on the stack. */ |
| 170 | template<typename T, typename... Arg> |
| 171 | void push_new (Arg... args) |
| 172 | { |
| 173 | m_operations.emplace_back (new T (std::forward<Arg> (args)...)); |
| 174 | } |
| 175 | |
| 176 | /* Push a new C string operation. */ |
| 177 | void push_c_string (int, struct stoken_vector *vec); |
| 178 | |
| 179 | /* Push a symbol reference. If SYM is nullptr, look for a minimal |
| 180 | symbol. */ |
| 181 | void push_symbol (const char *name, block_symbol sym); |
| 182 | |
| 183 | /* Push a reference to $mumble. This may result in a convenience |
| 184 | variable, a history reference, or a register. */ |
| 185 | void push_dollar (struct stoken str); |
| 186 | |
| 187 | /* Pop an operation from the stack. */ |
| 188 | expr::operation_up pop () |
| 189 | { |
| 190 | expr::operation_up result = std::move (m_operations.back ()); |
| 191 | m_operations.pop_back (); |
| 192 | return result; |
| 193 | } |
| 194 | |
| 195 | /* Pop N elements from the stack and return a vector. */ |
| 196 | std::vector<expr::operation_up> pop_vector (int n) |
| 197 | { |
| 198 | std::vector<expr::operation_up> result (n); |
| 199 | for (int i = 1; i <= n; ++i) |
| 200 | result[n - i] = pop (); |
| 201 | return result; |
| 202 | } |
| 203 | |
| 204 | /* A helper that pops an operation, wraps it in some other |
| 205 | operation, and pushes it again. */ |
| 206 | template<typename T> |
| 207 | void wrap () |
| 208 | { |
| 209 | using namespace expr; |
| 210 | operation_up v = ::expr::make_operation<T> (pop ()); |
| 211 | push (std::move (v)); |
| 212 | } |
| 213 | |
| 214 | /* A helper that pops two operations, wraps them in some other |
| 215 | operation, and pushes the result. */ |
| 216 | template<typename T> |
| 217 | void wrap2 () |
| 218 | { |
| 219 | expr::operation_up rhs = pop (); |
| 220 | expr::operation_up lhs = pop (); |
| 221 | push (expr::make_operation<T> (std::move (lhs), std::move (rhs))); |
| 222 | } |
| 223 | |
| 224 | /* If this is nonzero, this block is used as the lexical context for |
| 225 | symbol names. */ |
| 226 | |
| 227 | const struct block * const expression_context_block; |
| 228 | |
| 229 | /* If expression_context_block is non-zero, then this is the PC |
| 230 | within the block that we want to evaluate expressions at. When |
| 231 | debugging C or C++ code, we use this to find the exact line we're |
| 232 | at, and then look up the macro definitions active at that |
| 233 | point. */ |
| 234 | const CORE_ADDR expression_context_pc; |
| 235 | |
| 236 | /* Nonzero means stop parsing on first comma (if not within parentheses). */ |
| 237 | |
| 238 | int comma_terminates; |
| 239 | |
| 240 | /* During parsing of a C expression, the pointer to the next character |
| 241 | is in this variable. */ |
| 242 | |
| 243 | const char *lexptr; |
| 244 | |
| 245 | /* After a token has been recognized, this variable points to it. |
| 246 | Currently used only for error reporting. */ |
| 247 | const char *prev_lexptr = nullptr; |
| 248 | |
| 249 | /* Number of arguments seen so far in innermost function call. */ |
| 250 | |
| 251 | int arglist_len = 0; |
| 252 | |
| 253 | /* True if parsing an expression to attempt completion. */ |
| 254 | bool parse_completion; |
| 255 | |
| 256 | /* Completion state is updated here. */ |
| 257 | expr_completion_state m_completion_state; |
| 258 | |
| 259 | /* The innermost block tracker. */ |
| 260 | innermost_block_tracker *block_tracker; |
| 261 | |
| 262 | /* True if no value is expected from the expression. */ |
| 263 | bool void_context_p; |
| 264 | |
| 265 | private: |
| 266 | |
| 267 | /* Data structure for saving values of arglist_len for function calls whose |
| 268 | arguments contain other function calls. */ |
| 269 | |
| 270 | std::vector<int> m_funcall_chain; |
| 271 | |
| 272 | /* Stack of operations. */ |
| 273 | std::vector<expr::operation_up> m_operations; |
| 274 | }; |
| 275 | |
| 276 | /* When parsing expressions we track the innermost block that was |
| 277 | referenced. */ |
| 278 | |
| 279 | class innermost_block_tracker |
| 280 | { |
| 281 | public: |
| 282 | innermost_block_tracker (innermost_block_tracker_types types |
| 283 | = INNERMOST_BLOCK_FOR_SYMBOLS) |
| 284 | : m_types (types), |
| 285 | m_innermost_block (NULL) |
| 286 | { /* Nothing. */ } |
| 287 | |
| 288 | /* Update the stored innermost block if the new block B is more inner |
| 289 | than the currently stored block, or if no block is stored yet. The |
| 290 | type T tells us whether the block B was for a symbol or for a |
| 291 | register. The stored innermost block is only updated if the type T is |
| 292 | a type we are interested in, the types we are interested in are held |
| 293 | in M_TYPES and set during RESET. */ |
| 294 | void update (const struct block *b, innermost_block_tracker_types t); |
| 295 | |
| 296 | /* Overload of main UPDATE method which extracts the block from BS. */ |
| 297 | void update (const struct block_symbol &bs) |
| 298 | { |
| 299 | update (bs.block, INNERMOST_BLOCK_FOR_SYMBOLS); |
| 300 | } |
| 301 | |
| 302 | /* Return the stored innermost block. Can be nullptr if no symbols or |
| 303 | registers were found during an expression parse, and so no innermost |
| 304 | block was defined. */ |
| 305 | const struct block *block () const |
| 306 | { |
| 307 | return m_innermost_block; |
| 308 | } |
| 309 | |
| 310 | private: |
| 311 | /* The type of innermost block being looked for. */ |
| 312 | innermost_block_tracker_types m_types; |
| 313 | |
| 314 | /* The currently stored innermost block found while parsing an |
| 315 | expression. */ |
| 316 | const struct block *m_innermost_block; |
| 317 | }; |
| 318 | |
| 319 | /* A string token, either a char-string or bit-string. Char-strings are |
| 320 | used, for example, for the names of symbols. */ |
| 321 | |
| 322 | struct stoken |
| 323 | { |
| 324 | /* Pointer to first byte of char-string or first bit of bit-string. */ |
| 325 | const char *ptr; |
| 326 | /* Length of string in bytes for char-string or bits for bit-string. */ |
| 327 | int length; |
| 328 | }; |
| 329 | |
| 330 | struct typed_stoken |
| 331 | { |
| 332 | /* A language-specific type field. */ |
| 333 | int type; |
| 334 | /* Pointer to first byte of char-string or first bit of bit-string. */ |
| 335 | char *ptr; |
| 336 | /* Length of string in bytes for char-string or bits for bit-string. */ |
| 337 | int length; |
| 338 | }; |
| 339 | |
| 340 | struct stoken_vector |
| 341 | { |
| 342 | int len; |
| 343 | struct typed_stoken *tokens; |
| 344 | }; |
| 345 | |
| 346 | struct ttype |
| 347 | { |
| 348 | struct stoken stoken; |
| 349 | struct type *type; |
| 350 | }; |
| 351 | |
| 352 | struct symtoken |
| 353 | { |
| 354 | struct stoken stoken; |
| 355 | struct block_symbol sym; |
| 356 | int is_a_field_of_this; |
| 357 | }; |
| 358 | |
| 359 | struct objc_class_str |
| 360 | { |
| 361 | struct stoken stoken; |
| 362 | struct type *type; |
| 363 | int theclass; |
| 364 | }; |
| 365 | |
| 366 | extern const char *find_template_name_end (const char *); |
| 367 | |
| 368 | extern std::string copy_name (struct stoken); |
| 369 | |
| 370 | extern bool parse_float (const char *p, int len, |
| 371 | const struct type *type, gdb_byte *data); |
| 372 | \f |
| 373 | |
| 374 | /* Function used to avoid direct calls to fprintf |
| 375 | in the code generated by the bison parser. */ |
| 376 | |
| 377 | extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3); |
| 378 | |
| 379 | extern bool exp_uses_objfile (struct expression *exp, struct objfile *objfile); |
| 380 | |
| 381 | #endif /* PARSER_DEFS_H */ |
| 382 | |