1 /* Private partial symbol table definitions.
3 Copyright (C) 2009-2021 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 return ginfo
.obj_section (objfile
);
46 /* Return the unrelocated address of this partial symbol. */
47 CORE_ADDR
unrelocated_address () const
49 return ginfo
.value
.address
;
52 /* Return the address of this partial symbol, relocated according to
53 the offsets provided in OBJFILE. */
54 CORE_ADDR
address (const struct objfile
*objfile
) const
56 return (ginfo
.value
.address
57 + objfile
->section_offsets
[ginfo
.section_index ()]);
60 /* Set the address of this partial symbol. The address must be
62 void set_unrelocated_address (CORE_ADDR addr
)
64 ginfo
.value
.address
= addr
;
67 /* Note that partial_symbol does not derive from general_symbol_info
68 due to the bcache. See add_psymbol_to_bcache. */
70 struct general_symbol_info ginfo
;
72 /* Name space code. */
74 ENUM_BITFIELD(domain_enum_tag
) domain
: SYMBOL_DOMAIN_BITS
;
76 /* Address class (for info_symbols). Note that we don't allow
77 synthetic "aclass" values here at present, simply because there's
80 ENUM_BITFIELD(address_class
) aclass
: SYMBOL_ACLASS_BITS
;
83 /* A convenience enum to give names to some constants used when
84 searching psymtabs. This is internal to psymtab and should not be
87 enum psymtab_search_status
90 PST_SEARCHED_AND_FOUND
,
91 PST_SEARCHED_AND_NOT_FOUND
94 /* Specify whether a partial psymbol should be allocated on the global
95 list or the static list. */
97 enum class psymbol_placement
103 /* Each source file that has not been fully read in is represented by
104 a partial_symtab. This contains the information on where in the
105 executable the debugging symbols for a specific file are, and a
106 list of names of global symbols which are located in this file.
107 They are all chained on partial symtab lists.
109 Even after the source file has been read into a symtab, the
110 partial_symtab remains around. */
112 struct partial_symtab
114 /* Allocate a new partial symbol table associated with OBJFILE.
115 FILENAME (which must be non-NULL) is the filename of this partial
116 symbol table; it is copied into the appropriate storage. The
117 partial symtab will also be installed using
118 psymtab_storage::install. */
120 partial_symtab (const char *filename
, struct objfile
*objfile
)
121 ATTRIBUTE_NONNULL (2) ATTRIBUTE_NONNULL (3);
123 /* Like the above, but also sets the initial text low and text high
124 from the ADDR argument, and sets the global- and
127 partial_symtab (const char *filename
, struct objfile
*objfile
,
129 ATTRIBUTE_NONNULL (2) ATTRIBUTE_NONNULL (3);
131 virtual ~partial_symtab ()
135 /* Psymtab expansion is done in two steps:
136 - a call to read_symtab
137 - while that call is in progress, calls to expand_psymtab can be made,
138 both for this psymtab, and its dependencies.
139 This makes a distinction between a toplevel psymtab (for which both
140 read_symtab and expand_psymtab will be called) and a non-toplevel
141 psymtab (for which only expand_psymtab will be called). The
142 distinction can be used f.i. to do things before and after all
143 dependencies of a top-level psymtab have been expanded.
145 Read the full symbol table corresponding to this partial symbol
146 table. Typically calls expand_psymtab. */
147 virtual void read_symtab (struct objfile
*) = 0;
149 /* Expand the full symbol table for this partial symbol table. Typically
150 calls expand_dependencies. */
151 virtual void expand_psymtab (struct objfile
*) = 0;
153 /* Ensure that all the dependencies are read in. Calls
154 expand_psymtab for each non-shared dependency. */
155 void expand_dependencies (struct objfile
*);
157 /* Return true if the symtab corresponding to this psymtab has been
158 read in in the context of this objfile. */
159 virtual bool readin_p (struct objfile
*) const = 0;
161 /* Return a pointer to the compunit allocated for this source file
162 in the context of this objfile.
164 Return nullptr if the compunit was not read in or if there was no
166 virtual struct compunit_symtab
*get_compunit_symtab
167 (struct objfile
*) const = 0;
169 /* Return the raw low text address of this partial_symtab. */
170 CORE_ADDR
raw_text_low () const
175 /* Return the raw high text address of this partial_symtab. */
176 CORE_ADDR
raw_text_high () const
181 /* Return the relocated low text address of this partial_symtab. */
182 CORE_ADDR
text_low (struct objfile
*objfile
) const
184 return m_text_low
+ objfile
->text_section_offset ();
187 /* Return the relocated high text address of this partial_symtab. */
188 CORE_ADDR
text_high (struct objfile
*objfile
) const
190 return m_text_high
+ objfile
->text_section_offset ();
193 /* Set the low text address of this partial_symtab. */
194 void set_text_low (CORE_ADDR addr
)
200 /* Set the hight text address of this partial_symtab. */
201 void set_text_high (CORE_ADDR addr
)
207 /* Return true if this symtab is empty -- meaning that it contains
208 no symbols. It may still have dependencies. */
211 return global_psymbols
.empty () && static_psymbols
.empty ();
214 /* Add a symbol to this partial symbol table of OBJFILE.
216 If COPY_NAME is true, make a copy of NAME, otherwise use the passed
219 THECLASS is the type of symbol.
221 SECTION is the index of the section of OBJFILE in which the symbol is found.
223 WHERE determines whether the symbol goes in the list of static or global
226 COREADDR is the address of the symbol. For partial symbols that don't have
227 an address, zero is passed.
229 LANGUAGE is the language from which the symbol originates. This will
230 influence, amongst other things, how the symbol name is demangled. */
232 void add_psymbol (gdb::string_view name
,
233 bool copy_name
, domain_enum domain
,
234 enum address_class theclass
,
236 psymbol_placement where
,
238 enum language language
,
239 struct objfile
*objfile
);
241 /* Add a symbol to this partial symbol table of OBJFILE. The psymbol
242 must be fully constructed, and the names must be set and intern'd
245 void add_psymbol (const partial_symbol
&psym
,
246 psymbol_placement where
,
247 struct objfile
*objfile
);
250 /* Indicate that this partial symtab is complete. */
254 /* Chain of all existing partial symtabs. */
256 struct partial_symtab
*next
= nullptr;
258 /* Name of the source file which this partial_symtab defines,
259 or if the psymtab is anonymous then a descriptive name for
260 debugging purposes, or "". It must not be NULL. */
262 const char *filename
= nullptr;
264 /* Full path of the source file. NULL if not known. */
266 char *fullname
= nullptr;
268 /* Directory in which it was compiled, or NULL if we don't know. */
270 const char *dirname
= nullptr;
272 /* Range of text addresses covered by this file; texthigh is the
273 beginning of the next section. Do not use if PSYMTABS_ADDRMAP_SUPPORTED
274 is set. Do not refer directly to these fields. Instead, use the
275 accessors. The validity of these fields is determined by the
276 text_low_valid and text_high_valid fields; these are located later
277 in this structure for better packing. */
279 CORE_ADDR m_text_low
= 0;
280 CORE_ADDR m_text_high
= 0;
282 /* If NULL, this is an ordinary partial symbol table.
284 If non-NULL, this holds a single includer of this partial symbol
285 table, and this partial symbol table is a shared one.
287 A shared psymtab is one that is referenced by multiple other
288 psymtabs, and which conceptually has its contents directly
291 Shared psymtabs have special semantics. When a search finds a
292 symbol in a shared table, we instead return one of the non-shared
293 tables that include this one.
295 A shared psymtabs can be referred to by other shared ones.
297 The psymtabs that refer to a shared psymtab will list the shared
298 psymtab in their 'dependencies' array.
300 In DWARF terms, a shared psymtab is a DW_TAG_partial_unit; but
301 of course using a name based on that would be too confusing, so
302 "shared" was chosen instead.
304 Only a single user is needed because, when expanding a shared
305 psymtab, we only need to expand its "canonical" non-shared user.
306 The choice of which one should be canonical is left to the
307 debuginfo reader; it can be arbitrary. */
309 struct partial_symtab
*user
= nullptr;
311 /* Array of pointers to all of the partial_symtab's which this one
312 depends on. Since this array can only be set to previous or
313 the current (?) psymtab, this dependency tree is guaranteed not
314 to have any loops. "depends on" means that symbols must be read
315 for the dependencies before being read for this psymtab; this is
316 for type references in stabs, where if foo.c includes foo.h, declarations
317 in foo.h may use type numbers defined in foo.c. For other debugging
318 formats there may be no need to use dependencies. */
320 struct partial_symtab
**dependencies
= nullptr;
322 int number_of_dependencies
= 0;
324 /* Global symbol list. This list will be sorted after readin to
325 improve access. Binary search will be the usual method of
326 finding a symbol within it. */
328 std::vector
<partial_symbol
*> global_psymbols
;
330 /* Static symbol list. This list will *not* be sorted after readin;
331 to find a symbol in it, exhaustive search must be used. This is
332 reasonable because searches through this list will eventually
333 lead to either the read in of a files symbols for real (assumed
334 to take a *lot* of time; check) or an error (and we don't care
335 how long errors take). */
337 std::vector
<partial_symbol
*> static_psymbols
;
339 /* True iff objfile->psymtabs_addrmap is properly populated for this
340 partial_symtab. For discontiguous overlapping psymtabs is the only usable
341 info in PSYMTABS_ADDRMAP. */
343 bool psymtabs_addrmap_supported
= false;
345 /* True if the name of this partial symtab is not a source file name. */
347 bool anonymous
= false;
349 /* A flag that is temporarily used when searching psymtabs. */
351 ENUM_BITFIELD (psymtab_search_status
) searched_flag
: 2;
353 /* Validity of the m_text_low and m_text_high fields. */
355 unsigned int text_low_valid
: 1;
356 unsigned int text_high_valid
: 1;
359 /* A partial symtab that tracks the "readin" and "compunit_symtab"
360 information in the ordinary way -- by storing it directly in this
362 struct standard_psymtab
: public partial_symtab
364 standard_psymtab (const char *filename
, struct objfile
*objfile
)
365 : partial_symtab (filename
, objfile
)
369 standard_psymtab (const char *filename
, struct objfile
*objfile
,
371 : partial_symtab (filename
, objfile
, addr
)
375 bool readin_p (struct objfile
*) const override
380 struct compunit_symtab
*get_compunit_symtab (struct objfile
*) const override
382 return compunit_symtab
;
385 /* True if the symtab corresponding to this psymtab has been
390 /* Pointer to compunit eventually allocated for this source file, 0 if
391 !readin or if we haven't looked for the symtab after it was readin. */
393 struct compunit_symtab
*compunit_symtab
= nullptr;
396 /* A partial_symtab that works in the historical db way. This should
397 not be used in new code, but exists to transition the somewhat
398 unmaintained "legacy" debug formats. */
400 struct legacy_psymtab
: public standard_psymtab
402 legacy_psymtab (const char *filename
, struct objfile
*objfile
)
403 : standard_psymtab (filename
, objfile
)
407 legacy_psymtab (const char *filename
, struct objfile
*objfile
,
409 : standard_psymtab (filename
, objfile
, addr
)
413 void read_symtab (struct objfile
*objf
) override
415 if (legacy_read_symtab
)
416 (*legacy_read_symtab
) (this, objf
);
419 void expand_psymtab (struct objfile
*objf
) override
421 (*legacy_expand_psymtab
) (this, objf
);
424 /* Pointer to function which will read in the symtab corresponding to
427 void (*legacy_read_symtab
) (legacy_psymtab
*, struct objfile
*) = nullptr;
429 /* Pointer to function which will actually expand this psymtab into
432 void (*legacy_expand_psymtab
) (legacy_psymtab
*, struct objfile
*) = nullptr;
434 /* Information that lets read_symtab() locate the part of the symbol table
435 that this psymtab corresponds to. This information is private to the
436 format-dependent symbol reading routines. For further detail examine
437 the various symbol reading modules. */
439 void *read_symtab_private
= nullptr;
442 /* Used when recording partial symbol tables. On destruction,
443 discards any partial symbol tables that have been built. However,
444 the tables can be kept by calling the "keep" method. */
445 class psymtab_discarder
449 psymtab_discarder (struct objfile
*objfile
)
450 : m_objfile (objfile
),
451 m_psymtab (objfile
->partial_symtabs
->psymtabs
)
455 ~psymtab_discarder ()
457 if (m_objfile
!= NULL
)
458 m_objfile
->partial_symtabs
->discard_psymtabs_to (m_psymtab
);
461 /* Keep any partial symbol tables that were built. */
469 /* The objfile. If NULL this serves as a sentinel to indicate that
470 the psymtabs should be kept. */
471 struct objfile
*m_objfile
;
472 /* How far back to free. */
473 struct partial_symtab
*m_psymtab
;
476 #endif /* PSYMPRIV_H */