1 /* Parser definitions for GDB.
3 Copyright (C) 1986-2020 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 "expression.h"
32 class innermost_block_tracker
;
34 extern bool parser_debug
;
36 /* A class that can be used to build a "struct expression". */
40 /* Constructor. LANG is the language used to parse the expression.
41 And GDBARCH is the gdbarch to use during parsing. */
43 expr_builder (const struct language_defn
*lang
,
44 struct gdbarch
*gdbarch
);
46 DISABLE_COPY_AND_ASSIGN (expr_builder
);
48 /* Resize the allocated expression to the correct size, and return
49 it as an expression_up -- passing ownership to the caller. */
50 ATTRIBUTE_UNUSED_RESULT expression_up
release ();
52 /* Return the gdbarch that was passed to the constructor. */
54 struct gdbarch
*gdbarch ()
56 return expout
->gdbarch
;
59 /* Return the language that was passed to the constructor. */
61 const struct language_defn
*language ()
63 return expout
->language_defn
;
66 /* The size of the expression above. */
70 /* The expression related to this parser state. */
74 /* The number of elements already in the expression. This is used
75 to know where to put new elements. */
80 /* This is used for expression completion. */
82 struct expr_completion_state
84 /* The index of the last struct expression directly before a '.' or
85 '->'. This is set when parsing and is only used when completing a
86 field name. It is -1 if no dereference operation was found. */
87 int expout_last_struct
= -1;
89 /* If we are completing a tagged type name, this will be nonzero. */
90 enum type_code expout_tag_completion_type
= TYPE_CODE_UNDEF
;
92 /* The token for tagged type name completion. */
93 gdb::unique_xmalloc_ptr
<char> expout_completion_name
;
96 /* An instance of this type is instantiated during expression parsing,
97 and passed to the appropriate parser. It holds both inputs to the
98 parser, and result. */
100 struct parser_state
: public expr_builder
102 /* Constructor. LANG is the language used to parse the expression.
103 And GDBARCH is the gdbarch to use during parsing. */
105 parser_state (const struct language_defn
*lang
,
106 struct gdbarch
*gdbarch
,
107 const struct block
*context_block
,
108 CORE_ADDR context_pc
,
112 innermost_block_tracker
*tracker
)
113 : expr_builder (lang
, gdbarch
),
114 expression_context_block (context_block
),
115 expression_context_pc (context_pc
),
116 comma_terminates (comma
),
118 parse_completion (completion
),
119 block_tracker (tracker
)
123 DISABLE_COPY_AND_ASSIGN (parser_state
);
125 /* Begin counting arguments for a function call,
126 saving the data about any containing call. */
128 void start_arglist ()
130 m_funcall_chain
.push_back (arglist_len
);
134 /* Return the number of arguments in a function call just terminated,
135 and restore the data for the containing function call. */
139 int val
= arglist_len
;
140 arglist_len
= m_funcall_chain
.back ();
141 m_funcall_chain
.pop_back ();
145 /* Mark the current index as the starting location of a structure
146 expression. This is used when completing on field names. */
148 void mark_struct_expression ();
150 /* Indicate that the current parser invocation is completing a tag.
151 TAG is the type code of the tag, and PTR and LENGTH represent the
152 start of the tag name. */
154 void mark_completion_tag (enum type_code tag
, const char *ptr
, int length
);
157 /* If this is nonzero, this block is used as the lexical context for
160 const struct block
* const expression_context_block
;
162 /* If expression_context_block is non-zero, then this is the PC
163 within the block that we want to evaluate expressions at. When
164 debugging C or C++ code, we use this to find the exact line we're
165 at, and then look up the macro definitions active at that
167 const CORE_ADDR expression_context_pc
;
169 /* Nonzero means stop parsing on first comma (if not within parentheses). */
171 int comma_terminates
;
173 /* During parsing of a C expression, the pointer to the next character
174 is in this variable. */
178 /* After a token has been recognized, this variable points to it.
179 Currently used only for error reporting. */
180 const char *prev_lexptr
= nullptr;
182 /* Number of arguments seen so far in innermost function call. */
186 /* True if parsing an expression to attempt completion. */
187 int parse_completion
;
189 /* Completion state is updated here. */
190 expr_completion_state m_completion_state
;
192 /* The innermost block tracker. */
193 innermost_block_tracker
*block_tracker
;
197 /* Data structure for saving values of arglist_len for function calls whose
198 arguments contain other function calls. */
200 std::vector
<int> m_funcall_chain
;
203 /* When parsing expressions we track the innermost block that was
206 class innermost_block_tracker
209 innermost_block_tracker (innermost_block_tracker_types types
210 = INNERMOST_BLOCK_FOR_SYMBOLS
)
212 m_innermost_block (NULL
)
215 /* Update the stored innermost block if the new block B is more inner
216 than the currently stored block, or if no block is stored yet. The
217 type T tells us whether the block B was for a symbol or for a
218 register. The stored innermost block is only updated if the type T is
219 a type we are interested in, the types we are interested in are held
220 in M_TYPES and set during RESET. */
221 void update (const struct block
*b
, innermost_block_tracker_types t
);
223 /* Overload of main UPDATE method which extracts the block from BS. */
224 void update (const struct block_symbol
&bs
)
226 update (bs
.block
, INNERMOST_BLOCK_FOR_SYMBOLS
);
229 /* Return the stored innermost block. Can be nullptr if no symbols or
230 registers were found during an expression parse, and so no innermost
231 block was defined. */
232 const struct block
*block () const
234 return m_innermost_block
;
238 /* The type of innermost block being looked for. */
239 innermost_block_tracker_types m_types
;
241 /* The currently stored innermost block found while parsing an
243 const struct block
*m_innermost_block
;
246 /* A string token, either a char-string or bit-string. Char-strings are
247 used, for example, for the names of symbols. */
251 /* Pointer to first byte of char-string or first bit of bit-string. */
253 /* Length of string in bytes for char-string or bits for bit-string. */
259 /* A language-specific type field. */
261 /* Pointer to first byte of char-string or first bit of bit-string. */
263 /* Length of string in bytes for char-string or bits for bit-string. */
270 struct typed_stoken
*tokens
;
275 struct stoken stoken
;
281 struct stoken stoken
;
282 struct block_symbol sym
;
283 int is_a_field_of_this
;
286 struct objc_class_str
288 struct stoken stoken
;
293 /* Reverse an expression from suffix form (in which it is constructed)
294 to prefix form (in which we can conveniently print or execute it).
295 Ordinarily this always returns -1. However, if LAST_STRUCT
296 is not -1 (i.e., we are trying to complete a field name), it will
297 return the index of the subexpression which is the left-hand-side
298 of the struct operation at LAST_STRUCT. */
300 extern int prefixify_expression (struct expression
*expr
,
301 int last_struct
= -1);
303 extern void write_exp_elt_opcode (struct expr_builder
*, enum exp_opcode
);
305 extern void write_exp_elt_sym (struct expr_builder
*, struct symbol
*);
307 extern void write_exp_elt_longcst (struct expr_builder
*, LONGEST
);
309 extern void write_exp_elt_floatcst (struct expr_builder
*, const gdb_byte
*);
311 extern void write_exp_elt_type (struct expr_builder
*, struct type
*);
313 extern void write_exp_elt_intern (struct expr_builder
*, struct internalvar
*);
315 extern void write_exp_string (struct expr_builder
*, struct stoken
);
317 void write_exp_string_vector (struct expr_builder
*, int type
,
318 struct stoken_vector
*vec
);
320 extern void write_exp_bitstring (struct expr_builder
*, struct stoken
);
322 extern void write_exp_elt_block (struct expr_builder
*, const struct block
*);
324 extern void write_exp_elt_objfile (struct expr_builder
*,
325 struct objfile
*objfile
);
327 extern void write_exp_msymbol (struct expr_builder
*,
328 struct bound_minimal_symbol
);
330 extern void write_dollar_variable (struct parser_state
*, struct stoken str
);
332 extern const char *find_template_name_end (const char *);
334 extern std::string
copy_name (struct stoken
);
336 extern int dump_subexp (struct expression
*, struct ui_file
*, int);
338 extern int dump_subexp_body_standard (struct expression
*,
339 struct ui_file
*, int);
341 /* Dump (to STREAM) a function call like expression at position ELT in the
342 expression array EXP. Return a new value for ELT just after the
343 function call expression. */
345 extern int dump_subexp_body_funcall (struct expression
*exp
,
346 struct ui_file
*stream
, int elt
);
348 extern void operator_length (const struct expression
*, int, int *, int *);
350 extern void operator_length_standard (const struct expression
*, int, int *,
353 extern int operator_check_standard (struct expression
*exp
, int pos
,
355 (struct objfile
*objfile
, void *data
),
358 extern bool parse_float (const char *p
, int len
,
359 const struct type
*type
, gdb_byte
*data
);
361 /* These codes indicate operator precedences for expression printing,
362 least tightly binding first. */
363 /* Adding 1 to a precedence value is done for binary operators,
364 on the operand which is more tightly bound, so that operators
365 of equal precedence within that operand will get parentheses. */
366 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
367 they are used as the "surrounding precedence" to force
368 various kinds of things to be parenthesized. */
371 PREC_NULL
, PREC_COMMA
, PREC_ABOVE_COMMA
, PREC_ASSIGN
, PREC_LOGICAL_OR
,
372 PREC_LOGICAL_AND
, PREC_BITWISE_IOR
, PREC_BITWISE_AND
, PREC_BITWISE_XOR
,
373 PREC_EQUAL
, PREC_ORDER
, PREC_SHIFT
, PREC_ADD
, PREC_MUL
, PREC_REPEAT
,
374 PREC_HYPER
, PREC_PREFIX
, PREC_SUFFIX
, PREC_BUILTIN_FUNCTION
377 /* Table mapping opcodes into strings for printing operators
378 and precedences of the operators. */
383 enum exp_opcode opcode
;
384 /* Precedence of operator. These values are used only by comparisons. */
385 enum precedence precedence
;
387 /* For a binary operator: 1 iff right associate.
388 For a unary operator: 1 iff postfix. */
392 /* Information needed to print, prefixify, and evaluate expressions for
395 struct exp_descriptor
397 /* Print subexpression. */
398 void (*print_subexp
) (struct expression
*, int *, struct ui_file
*,
401 /* Returns number of exp_elements needed to represent an operator and
402 the number of subexpressions it takes. */
403 void (*operator_length
) (const struct expression
*, int, int*, int *);
405 /* Call OBJFILE_FUNC for any objfile found being referenced by the
406 single operator of EXP at position POS. Operator parameters are
407 located at positive (POS + number) offsets in EXP. OBJFILE_FUNC
408 should never be called with NULL OBJFILE. OBJFILE_FUNC should
409 get passed an arbitrary caller supplied DATA pointer. If it
410 returns non-zero value then (any other) non-zero value should be
411 immediately returned to the caller. Otherwise zero should be
413 int (*operator_check
) (struct expression
*exp
, int pos
,
414 int (*objfile_func
) (struct objfile
*objfile
,
418 /* Dump the rest of this (prefix) expression after the operator
419 itself has been printed. See dump_subexp_body_standard in
421 int (*dump_subexp_body
) (struct expression
*, struct ui_file
*, int);
423 /* Evaluate an expression. */
424 struct value
*(*evaluate_exp
) (struct type
*, struct expression
*,
429 /* Default descriptor containing standard definitions of all
431 extern const struct exp_descriptor exp_descriptor_standard
;
433 /* Functions used by language-specific extended operators to (recursively)
434 print/dump subexpressions. */
436 extern void print_subexp (struct expression
*, int *, struct ui_file
*,
439 extern void print_subexp_standard (struct expression
*, int *,
440 struct ui_file
*, enum precedence
);
442 /* Print a function call like expression to STREAM. This is called as a
443 helper function by which point the expression node identifying this as a
444 function call has already been stripped off and POS should point to the
445 number of function call arguments. EXP is the object containing the
446 list of expression elements. */
448 extern void print_subexp_funcall (struct expression
*exp
, int *pos
,
449 struct ui_file
*stream
);
451 /* Function used to avoid direct calls to fprintf
452 in the code generated by the bison parser. */
454 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
456 extern int exp_uses_objfile (struct expression
*exp
, struct objfile
*objfile
);
458 #endif /* PARSER_DEFS_H */