binutils-gdb/gdb/expression.h

149 lines
4.6 KiB
C

/* Definitions for expressions stored in reversed prefix form, for GDB.
Copyright (C) 1986, 1989, 1992, 1994, 2000, 2003, 2005, 2007-2012
Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#if !defined (EXPRESSION_H)
#define EXPRESSION_H 1
#include "symtab.h" /* Needed for "struct block" type. */
#include "doublest.h" /* Needed for DOUBLEST. */
/* Definitions for saved C expressions. */
/* An expression is represented as a vector of union exp_element's.
Each exp_element is an opcode, except that some opcodes cause
the following exp_element to be treated as a long or double constant
or as a variable. The opcodes are obeyed, using a stack for temporaries.
The value is left on the temporary stack at the end. */
/* When it is necessary to include a string,
it can occupy as many exp_elements as it needs.
We find the length of the string using strlen,
divide to find out how many exp_elements are used up,
and skip that many. Strings, like numbers, are indicated
by the preceding opcode. */
enum exp_opcode
{
#define OP(name) name ,
#include "std-operator.def"
/* First extension operator. Individual language modules define extra
operators in *.def include files below with numbers higher than
OP_EXTENDED0. */
OP (OP_EXTENDED0)
/* Language specific operators. */
#include "ada-operator.def"
#undef OP
/* Existing only to swallow the last comma (',') from last .inc file. */
OP_UNUSED_LAST
};
union exp_element
{
enum exp_opcode opcode;
struct symbol *symbol;
LONGEST longconst;
DOUBLEST doubleconst;
gdb_byte decfloatconst[16];
/* Really sizeof (union exp_element) characters (or less for the last
element of a string). */
char string;
struct type *type;
struct internalvar *internalvar;
struct block *block;
struct objfile *objfile;
};
struct expression
{
const struct language_defn *language_defn; /* language it was
entered in. */
struct gdbarch *gdbarch; /* architecture it was parsed in. */
int nelts;
union exp_element elts[1];
};
/* Macros for converting between number of expression elements and bytes
to store that many expression elements. */
#define EXP_ELEM_TO_BYTES(elements) \
((elements) * sizeof (union exp_element))
#define BYTES_TO_EXP_ELEM(bytes) \
(((bytes) + sizeof (union exp_element) - 1) / sizeof (union exp_element))
/* From parse.c */
extern struct expression *parse_expression (char *);
extern struct type *parse_field_expression (char *, char **);
extern struct expression *parse_exp_1 (char **, struct block *, int);
/* For use by parsers; set if we want to parse an expression and
attempt to complete a field name. */
extern int in_parse_field;
/* The innermost context required by the stack and register variables
we've encountered so far. To use this, set it to NULL, then call
parse_<whatever>, then look at it. */
extern struct block *innermost_block;
/* From eval.c */
/* Values of NOSIDE argument to eval_subexp. */
enum noside
{
EVAL_NORMAL,
EVAL_SKIP, /* Only effect is to increment pos. */
EVAL_AVOID_SIDE_EFFECTS /* Don't modify any variables or
call any functions. The value
returned will have the correct
type, and will have an
approximately correct lvalue
type (inaccuracy: anything that is
listed as being in a register in
the function in which it was
declared will be lval_register). */
};
extern struct value *evaluate_subexp_standard
(struct type *, struct expression *, int *, enum noside);
/* From expprint.c */
extern void print_expression (struct expression *, struct ui_file *);
extern char *op_name (struct expression *exp, enum exp_opcode opcode);
extern char *op_string (enum exp_opcode);
extern void dump_raw_expression (struct expression *,
struct ui_file *, char *);
extern void dump_prefix_expression (struct expression *, struct ui_file *);
#endif /* !defined (EXPRESSION_H) */