1 /* Private partial symbol table definitions.
3 Copyright (C) 2009-2020 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/>. */
25 #include "gdbsupport/gdb_string_view.h"
27 /* A partial_symbol records the name, domain, and address class of
28 symbols whose types we have not parsed yet. For functions, it also
29 contains their memory address, so we can find them from a PC value.
30 Each partial_symbol sits in a partial_symtab, all of which are chained
31 on a partial symtab list and which points to the corresponding
32 normal symtab once the partial_symtab has been referenced. */
34 /* This structure is space critical. See space comments at the top of
39 /* Return the section for this partial symbol, or nullptr if no
40 section has been set. */
41 struct obj_section
*obj_section (struct objfile
*objfile
) const
43 if (ginfo
.section
>= 0)
44 return &objfile
->sections
[ginfo
.section
];
48 /* Return the unrelocated address of this partial symbol. */
49 CORE_ADDR
unrelocated_address () const
51 return ginfo
.value
.address
;
54 /* Return the address of this partial symbol, relocated according to
55 the offsets provided in OBJFILE. */
56 CORE_ADDR
address (const struct objfile
*objfile
) const
58 return ginfo
.value
.address
+ objfile
->section_offsets
[ginfo
.section
];
61 /* Set the address of this partial symbol. The address must be
63 void set_unrelocated_address (CORE_ADDR addr
)
65 ginfo
.value
.address
= addr
;
68 /* Note that partial_symbol does not derive from general_symbol_info
69 due to the bcache. See add_psymbol_to_bcache. */
71 struct general_symbol_info ginfo
;
73 /* Name space code. */
75 ENUM_BITFIELD(domain_enum_tag
) domain
: SYMBOL_DOMAIN_BITS
;
77 /* Address class (for info_symbols). Note that we don't allow
78 synthetic "aclass" values here at present, simply because there's
81 ENUM_BITFIELD(address_class
) aclass
: SYMBOL_ACLASS_BITS
;
84 /* A convenience enum to give names to some constants used when
85 searching psymtabs. This is internal to psymtab and should not be
88 enum psymtab_search_status
91 PST_SEARCHED_AND_FOUND
,
92 PST_SEARCHED_AND_NOT_FOUND
95 /* Each source file that has not been fully read in is represented by
96 a partial_symtab. This contains the information on where in the
97 executable the debugging symbols for a specific file are, and a
98 list of names of global symbols which are located in this file.
99 They are all chained on partial symtab lists.
101 Even after the source file has been read into a symtab, the
102 partial_symtab remains around. They are allocated on an obstack,
105 struct partial_symtab
107 /* Allocate a new partial symbol table associated with OBJFILE.
108 FILENAME (which must be non-NULL) is the filename of this partial
109 symbol table; it is copied into the appropriate storage. The
110 partial symtab will also be installed using
111 psymtab_storage::install. */
113 partial_symtab (const char *filename
, struct objfile
*objfile
)
114 ATTRIBUTE_NONNULL (2) ATTRIBUTE_NONNULL (3);
116 /* Like the above, but also sets the initial text low and text high
117 from the ADDR argument, and sets the global- and
120 partial_symtab (const char *filename
, struct objfile
*objfile
,
122 ATTRIBUTE_NONNULL (2) ATTRIBUTE_NONNULL (3);
124 virtual ~partial_symtab ()
128 /* Read the full symbol table corresponding to this partial symbol
130 virtual void read_symtab (struct objfile
*) = 0;
132 /* Return the raw low text address of this partial_symtab. */
133 CORE_ADDR
raw_text_low () const
138 /* Return the raw high text address of this partial_symtab. */
139 CORE_ADDR
raw_text_high () const
144 /* Return the relocated low text address of this partial_symtab. */
145 CORE_ADDR
text_low (struct objfile
*objfile
) const
147 return m_text_low
+ objfile
->text_section_offset ();
150 /* Return the relocated high text address of this partial_symtab. */
151 CORE_ADDR
text_high (struct objfile
*objfile
) const
153 return m_text_high
+ objfile
->text_section_offset ();
156 /* Set the low text address of this partial_symtab. */
157 void set_text_low (CORE_ADDR addr
)
163 /* Set the hight text address of this partial_symtab. */
164 void set_text_high (CORE_ADDR addr
)
171 /* Chain of all existing partial symtabs. */
173 struct partial_symtab
*next
= nullptr;
175 /* Name of the source file which this partial_symtab defines,
176 or if the psymtab is anonymous then a descriptive name for
177 debugging purposes, or "". It must not be NULL. */
179 const char *filename
= nullptr;
181 /* Full path of the source file. NULL if not known. */
183 char *fullname
= nullptr;
185 /* Directory in which it was compiled, or NULL if we don't know. */
187 const char *dirname
= nullptr;
189 /* Range of text addresses covered by this file; texthigh is the
190 beginning of the next section. Do not use if PSYMTABS_ADDRMAP_SUPPORTED
191 is set. Do not refer directly to these fields. Instead, use the
192 accessors. The validity of these fields is determined by the
193 text_low_valid and text_high_valid fields; these are located later
194 in this structure for better packing. */
196 CORE_ADDR m_text_low
= 0;
197 CORE_ADDR m_text_high
= 0;
199 /* If NULL, this is an ordinary partial symbol table.
201 If non-NULL, this holds a single includer of this partial symbol
202 table, and this partial symbol table is a shared one.
204 A shared psymtab is one that is referenced by multiple other
205 psymtabs, and which conceptually has its contents directly
208 Shared psymtabs have special semantics. When a search finds a
209 symbol in a shared table, we instead return one of the non-shared
210 tables that include this one.
212 A shared psymtabs can be referred to by other shared ones.
214 The psymtabs that refer to a shared psymtab will list the shared
215 psymtab in their 'dependencies' array.
217 In DWARF terms, a shared psymtab is a DW_TAG_partial_unit; but
218 of course using a name based on that would be too confusing, so
219 "shared" was chosen instead.
221 Only a single user is needed because, when expanding a shared
222 psymtab, we only need to expand its "canonical" non-shared user.
223 The choice of which one should be canonical is left to the
224 debuginfo reader; it can be arbitrary. */
226 struct partial_symtab
*user
= nullptr;
228 /* Array of pointers to all of the partial_symtab's which this one
229 depends on. Since this array can only be set to previous or
230 the current (?) psymtab, this dependency tree is guaranteed not
231 to have any loops. "depends on" means that symbols must be read
232 for the dependencies before being read for this psymtab; this is
233 for type references in stabs, where if foo.c includes foo.h, declarations
234 in foo.h may use type numbers defined in foo.c. For other debugging
235 formats there may be no need to use dependencies. */
237 struct partial_symtab
**dependencies
= nullptr;
239 int number_of_dependencies
= 0;
241 /* Global symbol list. This list will be sorted after readin to
242 improve access. Binary search will be the usual method of
243 finding a symbol within it. globals_offset is an integer offset
244 within global_psymbols[]. */
246 int globals_offset
= 0;
247 int n_global_syms
= 0;
249 /* Static symbol list. This list will *not* be sorted after readin;
250 to find a symbol in it, exhaustive search must be used. This is
251 reasonable because searches through this list will eventually
252 lead to either the read in of a files symbols for real (assumed
253 to take a *lot* of time; check) or an error (and we don't care
254 how long errors take). This is an offset and size within
255 static_psymbols[]. */
257 int statics_offset
= 0;
258 int n_static_syms
= 0;
260 /* True if the symtab corresponding to this psymtab has been readin.
261 This is located here so that this structure packs better on
266 /* True iff objfile->psymtabs_addrmap is properly populated for this
267 partial_symtab. For discontiguous overlapping psymtabs is the only usable
268 info in PSYMTABS_ADDRMAP. */
270 bool psymtabs_addrmap_supported
= false;
272 /* True if the name of this partial symtab is not a source file name. */
274 bool anonymous
= false;
276 /* A flag that is temporarily used when searching psymtabs. */
278 ENUM_BITFIELD (psymtab_search_status
) searched_flag
: 2;
280 /* Validity of the m_text_low and m_text_high fields. */
282 unsigned int text_low_valid
: 1;
283 unsigned int text_high_valid
: 1;
285 /* Pointer to compunit eventually allocated for this source file, 0 if
286 !readin or if we haven't looked for the symtab after it was readin. */
288 struct compunit_symtab
*compunit_symtab
= nullptr;
291 /* A partial_symtab that works in the historical db way. This should
292 not be used in new code, but exists to transition the somewhat
293 unmaintained "legacy" debug formats. */
295 struct legacy_psymtab
: public partial_symtab
297 legacy_psymtab (const char *filename
, struct objfile
*objfile
)
298 : partial_symtab (filename
, objfile
)
302 legacy_psymtab (const char *filename
, struct objfile
*objfile
,
304 : partial_symtab (filename
, objfile
, addr
)
308 void read_symtab (struct objfile
*objf
) override
310 if (legacy_read_symtab
)
311 (*legacy_read_symtab
) (this, objf
);
314 /* Pointer to function which will read in the symtab corresponding to
317 void (*legacy_read_symtab
) (legacy_psymtab
*, struct objfile
*) = nullptr;
319 /* Information that lets read_symtab() locate the part of the symbol table
320 that this psymtab corresponds to. This information is private to the
321 format-dependent symbol reading routines. For further detail examine
322 the various symbol reading modules. */
324 void *read_symtab_private
= nullptr;
327 /* Specify whether a partial psymbol should be allocated on the global
328 list or the static list. */
330 enum class psymbol_placement
336 /* Add a symbol to the partial symbol table of OBJFILE.
338 If COPY_NAME is true, make a copy of NAME, otherwise use the passed
341 THECLASS is the type of symbol.
343 SECTION is the index of the section of OBJFILE in which the symbol is found.
345 WHERE determines whether the symbol goes in the list of static or global
346 partial symbols of OBJFILE.
348 COREADDR is the address of the symbol. For partial symbols that don't have
349 an address, zero is passed.
351 LANGUAGE is the language from which the symbol originates. This will
352 influence, amongst other things, how the symbol name is demangled. */
354 extern void add_psymbol_to_list (gdb::string_view name
,
355 bool copy_name
, domain_enum domain
,
356 enum address_class theclass
,
358 psymbol_placement where
,
360 enum language language
,
361 struct objfile
*objfile
);
363 /* Initialize storage for partial symbols. If partial symbol storage
364 has already been initialized, this does nothing. TOTAL_SYMBOLS is
365 an estimate of how many symbols there will be. */
367 extern void init_psymbol_list (struct objfile
*objfile
, int total_symbols
);
369 extern void end_psymtab_common (struct objfile
*, struct partial_symtab
*);
372 discard_psymtab (struct objfile
*objfile
, struct partial_symtab
*pst
)
374 objfile
->partial_symtabs
->discard_psymtab (pst
);
377 /* Used when recording partial symbol tables. On destruction,
378 discards any partial symbol tables that have been built. However,
379 the tables can be kept by calling the "keep" method. */
380 class psymtab_discarder
384 psymtab_discarder (struct objfile
*objfile
)
385 : m_objfile (objfile
),
386 m_psymtab (objfile
->partial_symtabs
->psymtabs
)
390 ~psymtab_discarder ()
392 if (m_objfile
!= NULL
)
393 m_objfile
->partial_symtabs
->discard_psymtabs_to (m_psymtab
);
396 /* Keep any partial symbol tables that were built. */
404 /* The objfile. If NULL this serves as a sentinel to indicate that
405 the psymtabs should be kept. */
406 struct objfile
*m_objfile
;
407 /* How far back to free. */
408 struct partial_symtab
*m_psymtab
;
411 #endif /* PSYMPRIV_H */