Introduce class psymtab_storage

This introduces a new psymtab_storage class, which holds all
psymbol-related objects that are independent of the objfile.  (This
latter contraint explains why psymbol_map was not moved; though this
could still be done with some work.)

This patch does not yet change where psymtab allocation is done --
that comes later.  This just wraps everything in a single object to
make further transformations simpler.

Note that a shared_ptr is used to link from the objfile to the
psymtab_storage object.  The end goal here is to allow a given symbol
reader to simply attach to the psymtab_storage object to the BFD, then
reuse it in later invocations; shared_ptr makes this simple to reason
about.

gdb/ChangeLog
2019-01-10  Tom Tromey  <tom@tromey.com>

	* symmisc.c (print_symbol_bcache_statistics): Update.
	(print_objfile_statistics): Update.
	* symfile.c (reread_symbols): Update.
	* psymtab.h (class psymtab_storage): New.
	* psymtab.c (psymtab_storage): New constructor.
	(~psymtab_storage): New destructor.
	(require_partial_symbols): Update.
	(ALL_OBJFILE_PSYMTABS_REQUIRED): Rewrite.
	(find_pc_sect_psymtab, find_pc_sect_psymbol)
	(match_partial_symbol, lookup_partial_symbol, dump_psymtab)
	(psym_dump, recursively_search_psymtabs, psym_has_symbols)
	(psym_find_compunit_symtab_by_address, sort_pst_symbols)
	(start_psymtab_common, end_psymtab_common)
	(add_psymbol_to_bcache, add_psymbol_to_list, init_psymbol_list)
	(allocate_psymtab): Update.
	(psymtab_storage::discard_psymtab): Rename from discard_psymtab.
	Update.
	(dump_psymtab_addrmap, maintenance_print_psymbols)
	(maintenance_check_psymtabs): Update.
	(class objfile_psymtabs): Move to objfiles.h.
	* psympriv.h (discard_psymtab): Now inline.
	(psymtab_discarder::psymtab_discarder): Update.
	(psymtab_discarder::~psymtab_discarder): Update.
	(ALL_OBJFILE_PSYMTABS): Rewrite.
	* objfiles.h (struct objfile) <psymtabs, psymtabs_addrmap,
	free_psymtabs, psymbol_cache, global_psymbols, static_psymbols>:
	Remove fields.
	<partial_symtabs>: New field.
	(class objfile_psymtabs): Move from psymtab.h.  Update.
	* objfiles.c (objfile::objfile): Initialize partial_symtabs, not
	psymbol_cache.
	(objfile::~objfile): Don't destroy psymbol_cache.
	* mdebugread.c (parse_partial_symbols): Update.
	* dwarf2read.c (create_addrmap_from_index)
	(create_addrmap_from_aranges, dw2_find_pc_sect_compunit_symtab)
	(process_psymtab_comp_unit_reader, dwarf2_build_psymtabs_hard)
	(add_partial_subprogram, dwarf2_ranges_read): Update.
	* dwarf-index-write.c (write_address_map)
	(write_one_signatured_type, recursively_write_psymbols)
	(class debug_names, class debug_names, write_psymtabs_to_index):
	Update.

1 files changed, 16 insertions, 26 deletions

diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index c0fc36f..94b415c 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -27,6 +27,7 @@
 #include "progspace.h"
 #include "registry.h"
 #include "gdb_bfd.h"
+#include "psymtab.h"
 #include <vector>
 #include "common/next-iterator.h"
 #include "common/safe-iterator.h"
@@ -321,22 +322,9 @@ struct objfile
 
   struct compunit_symtab *compunit_symtabs = nullptr;
 
-  /* Each objfile points to a linked list of partial symtabs derived from
-     this file, one partial symtab structure for each compilation unit
-     (source file).  */
+  /* The partial symbol tables.  */
 
-  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.  */
-
-  struct addrmap *psymtabs_addrmap = nullptr;
-
-  /* List of freed partial symtabs, available for re-use.  */
-
-  struct partial_symtab *free_psymtabs = nullptr;
+  std::shared_ptr<psymtab_storage> partial_symtabs;
 
   /* The object file's BFD.  Can be null if the objfile contains only
      minimal symbols, e.g. the run time common symbols for SunOS4.  */
@@ -358,22 +346,11 @@ struct objfile
 
   struct obstack objfile_obstack {};
 
-  /* A byte cache where we can stash arbitrary "chunks" of bytes that
-     will not change.  */
-
-  struct psymbol_bcache *psymbol_cache;
-
   /* Map symbol addresses to the partial symtab that defines the
      object at that address.  */
 
   std::vector<std::pair<CORE_ADDR, partial_symtab *>> psymbol_map;
 
-  /* Vectors of all partial symbols read in from file.  The actual data
-     is stored in the objfile_obstack.  */
-
-  std::vector<partial_symbol *> global_psymbols;
-  std::vector<partial_symbol *> static_psymbols;
-
   /* Structure which keeps track of functions that manipulate objfile's
      of the same type as this objfile.  I.e. the function to read partial
      symbols for example.  Note that this structure is in statically
@@ -697,6 +674,19 @@ private:
   struct objfile *m_objfile;
 };
 
+/* A range adapter that makes it possible to iterate over all
+   psymtabs in one objfile.  */
+
+class objfile_psymtabs : public next_adapter<struct partial_symtab>
+{
+public:
+
+  explicit objfile_psymtabs (struct objfile *objfile)
+    : next_adapter<struct partial_symtab> (objfile->partial_symtabs->psymtabs)
+  {
+  }
+};
+
 #define ALL_OBJFILE_OSECTIONS(objfile, osect)	\
   for (osect = objfile->sections; osect < objfile->sections_end; osect++) \
     if (osect->the_bfd_section == NULL)					\