X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Fpsymtab.h;h=e8bafbe4338f8cd32e79fea653b17704708331b5;hb=a350efd4fb368a35ada608f6bc26ccd3bed0ae6b;hp=17ceb22c8a19c8cd76a25e76b68232a27c13236a;hpb=927aa2e778dce440f4de5de8fc37ead1683a804e;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/psymtab.h b/gdb/psymtab.h index 17ceb22c8a..e8bafbe433 100644 --- a/gdb/psymtab.h +++ b/gdb/psymtab.h @@ -1,6 +1,6 @@ /* Public partial symbol table definitions. - Copyright (C) 2009-2017 Free Software Foundation, Inc. + Copyright (C) 2009-2020 Free Software Foundation, Inc. This file is part of GDB. @@ -20,15 +20,129 @@ #ifndef PSYMTAB_H #define PSYMTAB_H +#include "gdb_obstack.h" #include "symfile.h" +#include "gdbsupport/next-iterator.h" +#include "bcache.h" -/* A bcache for partial symbols. */ +struct partial_symbol; -struct psymbol_bcache; +/* An instance of this class manages the partial symbol tables and + partial symbols for a given objfile. + + The core psymtab functions -- those in psymtab.c -- arrange for + nearly all psymtab- and psymbol-related allocations to happen + either in the psymtab_storage object (either on its obstack or in + other memory managed by this class), or on the per-BFD object. The + only link from the psymtab storage object back to the objfile (or + objfile_obstack) that is made by the core psymtab code is the + compunit_symtab member in the standard_psymtab -- and a given + symbol reader can avoid this by implementing its own subclasses of + partial_symtab. + + However, it is up to each symbol reader to maintain this invariant + in other ways, if it wants to reuse psymtabs across multiple + objfiles. The main issue here is ensuring that read_symtab_private + does not point into objfile_obstack. */ + +class psymtab_storage +{ +public: + + psymtab_storage (); + + ~psymtab_storage (); + + DISABLE_COPY_AND_ASSIGN (psymtab_storage); + + /* Discard all partial symbol tables starting with "psymtabs" and + proceeding until "to" has been discarded. */ + + void discard_psymtabs_to (struct partial_symtab *to) + { + while (psymtabs != to) + discard_psymtab (psymtabs); + } + + /* Discard the partial symbol table. */ + + void discard_psymtab (struct partial_symtab *pst); + + /* Return the obstack that is used for storage by this object. */ + + struct obstack *obstack () + { + if (!m_obstack.has_value ()) + m_obstack.emplace (); + return &*m_obstack; + } + + /* Allocate storage for the "dependencies" field of a psymtab. + NUMBER says how many dependencies there are. */ + + struct partial_symtab **allocate_dependencies (int number) + { + return OBSTACK_CALLOC (obstack (), number, struct partial_symtab *); + } + + /* Install a psymtab on the psymtab list. This transfers ownership + of PST to this object. */ + + void install_psymtab (partial_symtab *pst); + + typedef next_adapter partial_symtab_range; + + /* A range adapter that makes it possible to iterate over all + psymtabs in one objfile. */ + + partial_symtab_range range () + { + return partial_symtab_range (psymtabs); + } + + + /* Each objfile points to a linked list of partial symtabs derived from + this file, one partial symtab structure for each compilation unit + (source file). */ + + struct partial_symtab *psymtabs = nullptr; + + /* Map addresses to the entries of PSYMTABS. It would be more efficient to + have a map per the whole process but ADDRMAP cannot selectively remove + its items during FREE_OBJFILE. This mapping is already present even for + PARTIAL_SYMTABs which still have no corresponding full SYMTABs read. + + The DWARF parser reuses this addrmap to store things other than + psymtabs in the cases where debug information is being read from, for + example, the .debug-names section. */ + + struct addrmap *psymtabs_addrmap = nullptr; + + /* A byte cache where we can stash arbitrary "chunks" of bytes that + will not change. */ + + gdb::bcache psymbol_cache; + + /* Vectors of all partial symbols read in from file. The actual data + is stored in the objfile_obstack. */ + + std::vector global_psymbols; + std::vector static_psymbols; + + /* Stack of vectors of partial symbols, using during psymtab + initialization. */ + + std::vector*> current_global_psymbols; + std::vector*> current_static_psymbols; + +private: + + /* The obstack where allocations are made. This is lazily allocated + so that we don't waste memory when there are no psymtabs. */ + + gdb::optional m_obstack; +}; -extern struct psymbol_bcache *psymbol_bcache_init (void); -extern void psymbol_bcache_free (struct psymbol_bcache *); -extern struct bcache *psymbol_bcache_get_bcache (struct psymbol_bcache *); extern const struct quick_symbol_functions psym_functions; @@ -36,11 +150,11 @@ extern const struct quick_symbol_functions dwarf2_gdb_index_functions; extern const struct quick_symbol_functions dwarf2_debug_names_functions; /* Ensure that the partial symbols for OBJFILE have been loaded. If - VERBOSE is non-zero, then this will print a message when symbols - are loaded. This function always returns its argument, as a - convenience. */ + VERBOSE is true, then this will print a message when symbols + are loaded. This function returns a range adapter suitable for + iterating over the psymtabs of OBJFILE. */ -extern struct objfile *require_partial_symbols (struct objfile *objfile, - int verbose); +extern psymtab_storage::partial_symtab_range require_partial_symbols + (struct objfile *objfile, bool verbose); #endif /* PSYMTAB_H */