1 /* Parser definitions for GDB.
3 Copyright (C) 1986-2019 Free Software Foundation, Inc.
5 Modified from expread.y by the Department of Computer Science at the
6 State University of New York at Buffalo.
8 This file is part of GDB.
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.
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.
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/>. */
23 #if !defined (PARSER_DEFS_H)
24 #define PARSER_DEFS_H 1
26 #include "common/vec.h"
27 #include "expression.h"
33 extern int parser_debug;
35 /* A class that can be used to build a "struct expression". */
39 /* Constructor. LANG is the language used to parse the expression.
40 And GDBARCH is the gdbarch to use during parsing. */
42 expr_builder (const struct language_defn *lang,
43 struct gdbarch *gdbarch);
45 DISABLE_COPY_AND_ASSIGN (expr_builder);
47 /* Resize the allocated expression to the correct size, and return
48 it as an expression_up -- passing ownership to the caller. */
49 ATTRIBUTE_UNUSED_RESULT expression_up release ();
51 /* Return the gdbarch that was passed to the constructor. */
53 struct gdbarch *gdbarch ()
55 return expout->gdbarch;
58 /* Return the language that was passed to the constructor. */
60 const struct language_defn *language ()
62 return expout->language_defn;
65 /* The size of the expression above. */
69 /* The expression related to this parser state. */
73 /* The number of elements already in the expression. This is used
74 to know where to put new elements. */
79 /* An instance of this type is instantiated during expression parsing,
80 and passed to the appropriate parser. It holds both inputs to the
81 parser, and result. */
83 struct parser_state : public expr_builder
85 /* Constructor. LANG is the language used to parse the expression.
86 And GDBARCH is the gdbarch to use during parsing. */
88 parser_state (const struct language_defn *lang,
89 struct gdbarch *gdbarch,
90 const struct block *context_block,
92 : expr_builder (lang, gdbarch),
93 expression_context_block (context_block),
94 expression_context_pc (context_pc)
98 DISABLE_COPY_AND_ASSIGN (parser_state);
100 /* If this is nonzero, this block is used as the lexical context for
103 const struct block * const expression_context_block;
105 /* If expression_context_block is non-zero, then this is the PC
106 within the block that we want to evaluate expressions at. When
107 debugging C or C++ code, we use this to find the exact line we're
108 at, and then look up the macro definitions active at that
110 const CORE_ADDR expression_context_pc;
113 /* When parsing expressions we track the innermost block that was
116 class innermost_block_tracker
119 innermost_block_tracker ()
120 : m_types (INNERMOST_BLOCK_FOR_SYMBOLS),
121 m_innermost_block (NULL)
124 /* Reset the currently stored innermost block. Usually called before
125 parsing a new expression. As the most common case is that we only
126 want to gather the innermost block for symbols in an expression, this
127 becomes the default block tracker type. */
128 void reset (innermost_block_tracker_types t = INNERMOST_BLOCK_FOR_SYMBOLS)
131 m_innermost_block = NULL;
134 /* Update the stored innermost block if the new block B is more inner
135 than the currently stored block, or if no block is stored yet. The
136 type T tells us whether the block B was for a symbol or for a
137 register. The stored innermost block is only updated if the type T is
138 a type we are interested in, the types we are interested in are held
139 in M_TYPES and set during RESET. */
140 void update (const struct block *b, innermost_block_tracker_types t);
142 /* Overload of main UPDATE method which extracts the block from BS. */
143 void update (const struct block_symbol &bs)
145 update (bs.block, INNERMOST_BLOCK_FOR_SYMBOLS);
148 /* Return the stored innermost block. Can be nullptr if no symbols or
149 registers were found during an expression parse, and so no innermost
150 block was defined. */
151 const struct block *block () const
153 return m_innermost_block;
157 /* The type of innermost block being looked for. */
158 innermost_block_tracker_types m_types;
160 /* The currently stored innermost block found while parsing an
162 const struct block *m_innermost_block;
165 /* The innermost context required by the stack and register variables
166 we've encountered so far. This is cleared by the expression
167 parsing functions before parsing an expression, and can queried
168 once the parse is complete. */
169 extern innermost_block_tracker innermost_block;
171 /* Number of arguments seen so far in innermost function call. */
172 extern int arglist_len;
174 /* A string token, either a char-string or bit-string. Char-strings are
175 used, for example, for the names of symbols. */
179 /* Pointer to first byte of char-string or first bit of bit-string. */
181 /* Length of string in bytes for char-string or bits for bit-string. */
187 /* A language-specific type field. */
189 /* Pointer to first byte of char-string or first bit of bit-string. */
191 /* Length of string in bytes for char-string or bits for bit-string. */
198 struct typed_stoken *tokens;
203 struct stoken stoken;
209 struct stoken stoken;
210 struct block_symbol sym;
211 int is_a_field_of_this;
214 struct objc_class_str
216 struct stoken stoken;
221 /* For parsing of complicated types.
222 An array should be preceded in the list by the size of the array. */
231 tp_function_with_arguments,
238 /* The stack can contain either an enum type_pieces or an int. */
241 enum type_pieces piece;
243 struct type_stack *stack_val;
244 std::vector<struct type *> *typelist_val;
247 /* The type stack is an instance of this structure. */
251 /* Elements on the stack. */
252 std::vector<union type_stack_elt> elements;
255 /* Reverse an expression from suffix form (in which it is constructed)
256 to prefix form (in which we can conveniently print or execute it).
257 Ordinarily this always returns -1. However, if EXPOUT_LAST_STRUCT
258 is not -1 (i.e., we are trying to complete a field name), it will
259 return the index of the subexpression which is the left-hand-side
260 of the struct operation at EXPOUT_LAST_STRUCT. */
262 extern int prefixify_expression (struct expression *expr);
264 extern void write_exp_elt_opcode (struct expr_builder *, enum exp_opcode);
266 extern void write_exp_elt_sym (struct expr_builder *, struct symbol *);
268 extern void write_exp_elt_longcst (struct expr_builder *, LONGEST);
270 extern void write_exp_elt_floatcst (struct expr_builder *, const gdb_byte *);
272 extern void write_exp_elt_type (struct expr_builder *, struct type *);
274 extern void write_exp_elt_intern (struct expr_builder *, struct internalvar *);
276 extern void write_exp_string (struct expr_builder *, struct stoken);
278 void write_exp_string_vector (struct expr_builder *, int type,
279 struct stoken_vector *vec);
281 extern void write_exp_bitstring (struct expr_builder *, struct stoken);
283 extern void write_exp_elt_block (struct expr_builder *, const struct block *);
285 extern void write_exp_elt_objfile (struct expr_builder *,
286 struct objfile *objfile);
288 extern void write_exp_msymbol (struct expr_builder *,
289 struct bound_minimal_symbol);
291 extern void write_dollar_variable (struct parser_state *, struct stoken str);
293 extern void mark_struct_expression (struct expr_builder *);
295 extern const char *find_template_name_end (const char *);
297 extern void start_arglist (void);
299 extern int end_arglist (void);
301 extern char *copy_name (struct stoken);
303 extern void insert_type (enum type_pieces);
305 extern void push_type (enum type_pieces);
307 extern void push_type_int (int);
309 extern void insert_type_address_space (struct expr_builder *, char *);
311 extern enum type_pieces pop_type (void);
313 extern int pop_type_int (void);
315 extern struct type_stack *get_type_stack (void);
317 extern struct type_stack *append_type_stack (struct type_stack *to,
318 struct type_stack *from);
320 extern void push_type_stack (struct type_stack *stack);
322 extern void push_typelist (std::vector<struct type *> *typelist);
324 extern int dump_subexp (struct expression *, struct ui_file *, int);
326 extern int dump_subexp_body_standard (struct expression *,
327 struct ui_file *, int);
329 extern void operator_length (const struct expression *, int, int *, int *);
331 extern void operator_length_standard (const struct expression *, int, int *,
334 extern int operator_check_standard (struct expression *exp, int pos,
336 (struct objfile *objfile, void *data),
339 extern const char *op_name_standard (enum exp_opcode);
341 extern struct type *follow_types (struct type *);
343 extern type_instance_flags follow_type_instance_flags ();
345 extern void null_post_parser (expression_up *, int);
347 extern bool parse_float (const char *p, int len,
348 const struct type *type, gdb_byte *data);
350 /* During parsing of a C expression, the pointer to the next character
351 is in this variable. */
353 extern const char *lexptr;
355 /* After a token has been recognized, this variable points to it.
356 Currently used only for error reporting. */
357 extern const char *prev_lexptr;
359 /* Current depth in parentheses within the expression. */
361 extern int paren_depth;
363 /* Nonzero means stop parsing on first comma (if not within parentheses). */
365 extern int comma_terminates;
367 /* These codes indicate operator precedences for expression printing,
368 least tightly binding first. */
369 /* Adding 1 to a precedence value is done for binary operators,
370 on the operand which is more tightly bound, so that operators
371 of equal precedence within that operand will get parentheses. */
372 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
373 they are used as the "surrounding precedence" to force
374 various kinds of things to be parenthesized. */
377 PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
378 PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
379 PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
380 PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
383 /* Table mapping opcodes into strings for printing operators
384 and precedences of the operators. */
389 enum exp_opcode opcode;
390 /* Precedence of operator. These values are used only by comparisons. */
391 enum precedence precedence;
393 /* For a binary operator: 1 iff right associate.
394 For a unary operator: 1 iff postfix. */
398 /* Information needed to print, prefixify, and evaluate expressions for
401 struct exp_descriptor
403 /* Print subexpression. */
404 void (*print_subexp) (struct expression *, int *, struct ui_file *,
407 /* Returns number of exp_elements needed to represent an operator and
408 the number of subexpressions it takes. */
409 void (*operator_length) (const struct expression*, int, int*, int *);
411 /* Call OBJFILE_FUNC for any objfile found being referenced by the
412 single operator of EXP at position POS. Operator parameters are
413 located at positive (POS + number) offsets in EXP. OBJFILE_FUNC
414 should never be called with NULL OBJFILE. OBJFILE_FUNC should
415 get passed an arbitrary caller supplied DATA pointer. If it
416 returns non-zero value then (any other) non-zero value should be
417 immediately returned to the caller. Otherwise zero should be
419 int (*operator_check) (struct expression *exp, int pos,
420 int (*objfile_func) (struct objfile *objfile,
424 /* Name of this operator for dumping purposes.
425 The returned value should never be NULL, even if EXP_OPCODE is
426 an unknown opcode (a string containing an image of the numeric
427 value of the opcode can be returned, for instance). */
428 const char *(*op_name) (enum exp_opcode);
430 /* Dump the rest of this (prefix) expression after the operator
431 itself has been printed. See dump_subexp_body_standard in
433 int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
435 /* Evaluate an expression. */
436 struct value *(*evaluate_exp) (struct type *, struct expression *,
441 /* Default descriptor containing standard definitions of all
443 extern const struct exp_descriptor exp_descriptor_standard;
445 /* Functions used by language-specific extended operators to (recursively)
446 print/dump subexpressions. */
448 extern void print_subexp (struct expression *, int *, struct ui_file *,
451 extern void print_subexp_standard (struct expression *, int *,
452 struct ui_file *, enum precedence);
454 /* Function used to avoid direct calls to fprintf
455 in the code generated by the bison parser. */
457 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
459 extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
461 extern void mark_completion_tag (enum type_code, const char *ptr,
464 #endif /* PARSER_DEFS_H */