1 /* Definitions for expressions stored in reversed prefix form, for GDB.
3 Copyright (C) 1986-2017 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #if !defined (EXPRESSION_H)
21 #define EXPRESSION_H 1
24 #include "symtab.h" /* Needed for "struct block" type. */
25 #include "doublest.h" /* Needed for DOUBLEST. */
28 /* Definitions for saved C expressions. */
30 /* An expression is represented as a vector of union exp_element's.
31 Each exp_element is an opcode, except that some opcodes cause
32 the following exp_element to be treated as a long or double constant
33 or as a variable. The opcodes are obeyed, using a stack for temporaries.
34 The value is left on the temporary stack at the end. */
36 /* When it is necessary to include a string,
37 it can occupy as many exp_elements as it needs.
38 We find the length of the string using strlen,
39 divide to find out how many exp_elements are used up,
40 and skip that many. Strings, like numbers, are indicated
41 by the preceding opcode. */
45 #define OP(name) name ,
47 #include "std-operator.def"
49 /* First extension operator. Individual language modules define extra
50 operators in *.def include files below with numbers higher than
54 /* Language specific operators. */
55 #include "ada-operator.def"
59 /* Existing only to swallow the last comma (',') from last .inc file. */
65 enum exp_opcode opcode
;
66 struct symbol
*symbol
;
69 gdb_byte decfloatconst
[16];
70 /* Really sizeof (union exp_element) characters (or less for the last
71 element of a string). */
74 struct internalvar
*internalvar
;
75 const struct block
*block
;
76 struct objfile
*objfile
;
81 const struct language_defn
*language_defn
; /* language it was
83 struct gdbarch
*gdbarch
; /* architecture it was parsed in. */
85 union exp_element elts
[1];
88 typedef gdb::unique_xmalloc_ptr
<expression
> expression_up
;
90 /* Macros for converting between number of expression elements and bytes
91 to store that many expression elements. */
93 #define EXP_ELEM_TO_BYTES(elements) \
94 ((elements) * sizeof (union exp_element))
95 #define BYTES_TO_EXP_ELEM(bytes) \
96 (((bytes) + sizeof (union exp_element) - 1) / sizeof (union exp_element))
100 extern expression_up
parse_expression (const char *);
102 extern expression_up
parse_expression_with_language (const char *string
,
105 extern struct type
*parse_expression_for_completion (const char *, char **,
108 extern expression_up
parse_exp_1 (const char **, CORE_ADDR pc
,
109 const struct block
*, int);
111 /* For use by parsers; set if we want to parse an expression and
112 attempt completion. */
113 extern int parse_completion
;
115 /* The innermost context required by the stack and register variables
116 we've encountered so far. To use this, set it to NULL, then call
117 parse_<whatever>, then look at it. */
118 extern const struct block
*innermost_block
;
122 /* Values of NOSIDE argument to eval_subexp. */
127 EVAL_SKIP
, /* Only effect is to increment pos. */
128 EVAL_AVOID_SIDE_EFFECTS
/* Don't modify any variables or
129 call any functions. The value
130 returned will have the correct
131 type, and will have an
132 approximately correct lvalue
133 type (inaccuracy: anything that is
134 listed as being in a register in
135 the function in which it was
136 declared will be lval_register).
137 Ideally this would not even read
138 target memory, but currently it
139 does in many situations. */
142 extern struct value
*evaluate_subexp_standard
143 (struct type
*, struct expression
*, int *, enum noside
);
145 /* From expprint.c */
147 extern void print_expression (struct expression
*, struct ui_file
*);
149 extern const char *op_name (struct expression
*exp
, enum exp_opcode opcode
);
151 extern const char *op_string (enum exp_opcode
);
153 extern void dump_raw_expression (struct expression
*,
154 struct ui_file
*, const char *);
155 extern void dump_prefix_expression (struct expression
*, struct ui_file
*);
157 /* In an OP_RANGE expression, either bound could be empty, indicating
158 that its value is by default that of the corresponding bound of the
159 array or string. So we have four sorts of subrange. This
160 enumeration type is to identify this. */
164 BOTH_BOUND_DEFAULT
, /* "(:)" */
165 LOW_BOUND_DEFAULT
, /* "(:high)" */
166 HIGH_BOUND_DEFAULT
, /* "(low:)" */
167 NONE_BOUND_DEFAULT
/* "(low:high)" */
170 #endif /* !defined (EXPRESSION_H) */