1 /* Private partial symbol table definitions.
3 Copyright (C) 2009-2018 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/>. */
26 /* A partial_symbol records the name, domain, and address class of
27 symbols whose types we have not parsed yet. For functions, it also
28 contains their memory address, so we can find them from a PC value.
29 Each partial_symbol sits in a partial_symtab, all of which are chained
30 on a partial symtab list and which points to the corresponding
31 normal symtab once the partial_symtab has been referenced. */
33 /* This structure is space critical. See space comments at the top of
36 struct partial_symbol : public general_symbol_info
38 /* Return the section for this partial symbol, or nullptr if no
39 section has been set. */
40 struct obj_section *obj_section (struct objfile *objfile) const
43 return &objfile->sections[section];
47 /* Name space code. */
49 ENUM_BITFIELD(domain_enum_tag) domain : SYMBOL_DOMAIN_BITS;
51 /* Address class (for info_symbols). Note that we don't allow
52 synthetic "aclass" values here at present, simply because there's
55 ENUM_BITFIELD(address_class) aclass : SYMBOL_ACLASS_BITS;
58 /* A convenience enum to give names to some constants used when
59 searching psymtabs. This is internal to psymtab and should not be
62 enum psymtab_search_status
65 PST_SEARCHED_AND_FOUND,
66 PST_SEARCHED_AND_NOT_FOUND
69 /* Each source file that has not been fully read in is represented by
70 a partial_symtab. This contains the information on where in the
71 executable the debugging symbols for a specific file are, and a
72 list of names of global symbols which are located in this file.
73 They are all chained on partial symtab lists.
75 Even after the source file has been read into a symtab, the
76 partial_symtab remains around. They are allocated on an obstack,
81 /* Chain of all existing partial symtabs. */
83 struct partial_symtab *next;
85 /* Name of the source file which this partial_symtab defines,
86 or if the psymtab is anonymous then a descriptive name for
87 debugging purposes, or "". It must not be NULL. */
91 /* Full path of the source file. NULL if not known. */
95 /* Directory in which it was compiled, or NULL if we don't know. */
99 /* Range of text addresses covered by this file; texthigh is the
100 beginning of the next section. Do not use if PSYMTABS_ADDRMAP_SUPPORTED
106 /* If NULL, this is an ordinary partial symbol table.
108 If non-NULL, this holds a single includer of this partial symbol
109 table, and this partial symbol table is a shared one.
111 A shared psymtab is one that is referenced by multiple other
112 psymtabs, and which conceptually has its contents directly
115 Shared psymtabs have special semantics. When a search finds a
116 symbol in a shared table, we instead return one of the non-shared
117 tables that include this one.
119 A shared psymtabs can be referred to by other shared ones.
121 The psymtabs that refer to a shared psymtab will list the shared
122 psymtab in their 'dependencies' array.
124 In DWARF terms, a shared psymtab is a DW_TAG_partial_unit; but
125 of course using a name based on that would be too confusing, so
126 "shared" was chosen instead.
128 Only a single user is needed because, when expanding a shared
129 psymtab, we only need to expand its "canonical" non-shared user.
130 The choice of which one should be canonical is left to the
131 debuginfo reader; it can be arbitrary. */
133 struct partial_symtab *user;
135 /* Array of pointers to all of the partial_symtab's which this one
136 depends on. Since this array can only be set to previous or
137 the current (?) psymtab, this dependency tree is guaranteed not
138 to have any loops. "depends on" means that symbols must be read
139 for the dependencies before being read for this psymtab; this is
140 for type references in stabs, where if foo.c includes foo.h, declarations
141 in foo.h may use type numbers defined in foo.c. For other debugging
142 formats there may be no need to use dependencies. */
144 struct partial_symtab **dependencies;
146 int number_of_dependencies;
148 /* Global symbol list. This list will be sorted after readin to
149 improve access. Binary search will be the usual method of
150 finding a symbol within it. globals_offset is an integer offset
151 within global_psymbols[]. */
156 /* Static symbol list. This list will *not* be sorted after readin;
157 to find a symbol in it, exhaustive search must be used. This is
158 reasonable because searches through this list will eventually
159 lead to either the read in of a files symbols for real (assumed
160 to take a *lot* of time; check) or an error (and we don't care
161 how long errors take). This is an offset and size within
162 static_psymbols[]. */
167 /* Non-zero if the symtab corresponding to this psymtab has been
168 readin. This is located here so that this structure packs better
169 on 64-bit systems. */
171 unsigned char readin;
173 /* True iff objfile->psymtabs_addrmap is properly populated for this
174 partial_symtab. For discontiguous overlapping psymtabs is the only usable
175 info in PSYMTABS_ADDRMAP. */
177 unsigned char psymtabs_addrmap_supported;
179 /* True if the name of this partial symtab is not a source file name. */
181 unsigned char anonymous;
183 /* A flag that is temporarily used when searching psymtabs. */
185 ENUM_BITFIELD (psymtab_search_status) searched_flag : 2;
187 /* Pointer to compunit eventually allocated for this source file, 0 if
188 !readin or if we haven't looked for the symtab after it was readin. */
190 struct compunit_symtab *compunit_symtab;
192 /* Pointer to function which will read in the symtab corresponding to
195 void (*read_symtab) (struct partial_symtab *, struct objfile *);
197 /* Information that lets read_symtab() locate the part of the symbol table
198 that this psymtab corresponds to. This information is private to the
199 format-dependent symbol reading routines. For further detail examine
200 the various symbol reading modules. */
202 void *read_symtab_private;
205 /* Add any kind of symbol to a partial_symbol vector. */
207 extern void add_psymbol_to_list (const char *, int,
210 std::vector<partial_symbol *> *,
212 enum language, struct objfile *);
214 extern void init_psymbol_list (struct objfile *, int);
216 extern struct partial_symtab *start_psymtab_common (struct objfile *,
217 const char *, CORE_ADDR,
218 std::vector<partial_symbol *> &,
219 std::vector<partial_symbol *> &);
221 extern void end_psymtab_common (struct objfile *, struct partial_symtab *);
223 extern struct partial_symtab *allocate_psymtab (const char *,
225 ATTRIBUTE_NONNULL (1);
227 extern void discard_psymtab (struct objfile *, struct partial_symtab *);
229 /* Used when recording partial symbol tables. On destruction,
230 discards any partial symbol tables that have been built. However,
231 the tables can be kept by calling the "keep" method. */
232 class psymtab_discarder
236 psymtab_discarder (struct objfile *objfile)
237 : m_objfile (objfile),
238 m_psymtab (objfile->psymtabs)
242 ~psymtab_discarder ()
244 if (m_objfile != NULL)
245 while (m_objfile->psymtabs != m_psymtab)
246 discard_psymtab (m_objfile, m_objfile->psymtabs);
249 /* Keep any partial symbol tables that were built. */
257 /* The objfile. If NULL this serves as a sentinel to indicate that
258 the psymtabs should be kept. */
259 struct objfile *m_objfile;
260 /* How far back to free. */
261 struct partial_symtab *m_psymtab;
264 /* Traverse all psymtabs in one objfile. */
266 #define ALL_OBJFILE_PSYMTABS(objfile, p) \
267 for ((p) = (objfile) -> psymtabs; (p) != NULL; (p) = (p) -> next)
269 #endif /* PSYMPRIV_H */