#ifndef PSYMTAB_H
#define PSYMTAB_H
+#include "gdb_obstack.h"
#include "symfile.h"
#include "common/next-iterator.h"
struct psymbol_bcache;
/* An instance of this class manages the partial symbol tables and
- partial symbols for a given objfile. */
+ 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 psymtab.
+
+ 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:
- explicit psymtab_storage (struct objfile *objfile);
+ psymtab_storage ();
~psymtab_storage ();
struct obstack *obstack ()
{
- return m_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 *);
+ }
+
+ /* Allocate a new psymtab on the psymtab obstack. The new psymtab
+ will be linked in to the "psymtabs" list, but otherwise all other
+ fields will be zero. */
+
+ struct partial_symtab *allocate_psymtab ();
+
+ typedef next_adapter<struct partial_symtab> 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);
}
struct addrmap *psymtabs_addrmap = nullptr;
- /* List of freed partial symtabs, available for re-use. */
-
- struct partial_symtab *free_psymtabs = nullptr;
-
/* A byte cache where we can stash arbitrary "chunks" of bytes that
will not change. */
private:
- /* The obstack where allocations are made. */
+ /* List of freed partial symtabs, available for re-use. */
+
+ struct partial_symtab *free_psymtabs = nullptr;
+
+ /* The obstack where allocations are made. This is lazily allocated
+ so that we don't waste memory when there are no psymtabs. */
- struct obstack *m_obstack;
+ gdb::optional<auto_obstack> m_obstack;
};
are loaded. This function returns a range adapter suitable for
iterating over the psymtabs of OBJFILE. */
-class objfile_psymtabs;
-extern objfile_psymtabs require_partial_symbols (struct objfile *objfile,
- int verbose);
+extern psymtab_storage::partial_symtab_range require_partial_symbols
+ (struct objfile *objfile, int verbose);
#endif /* PSYMTAB_H */