Have partial symbol tables own psymbol vectors

Have partial symbol tables own psymbol vectors

Currently pointers to all partial symbols are stored in two vectors;
and then indices into these vectors are stored in each partial_symtab.

This patch changes this so that each partial symtab instead has
vectors of symbols.  add_psymbol_to_list can now be changed into a
method on partial_symtab as well.

My main motivation for doing this is that I am looking into calling
sort_pst_symbols in the background.  However, I haven't actually
implemented this yet.  (Also this may make it more feasible to also
sort the static psymbols, though I haven't tried that either.)

Also, though, this lets us remove the "current_global_psymbols"
vector, because now the callers can simply refer directly to the
psymtab that they are modifying (formerly this was implicit).

The main drawback of this patch is that it increases the size of
partial symtab.

gdb/ChangeLog
2020-10-17  Tom Tromey  <tom@tromey.com>

	* xcoffread.c (xcoff_end_psymtab): Use partial_symtab::empty.
	(scan_xcoff_symtab): Update.
	* psymtab.h (class psymtab_storage) <global_psymbols,
	static_psymbols, current_global_psymbols,
	current_static_psymbols>: Remove.
	* psymtab.c (require_partial_symbols, find_pc_sect_psymbol)
	(match_partial_symbol, lookup_partial_symbol): Update.
	(print_partial_symbols): Change parameters.
	(dump_psymtab, recursively_search_psymtabs)
	(psym_fill_psymbol_map, psym_find_compunit_symtab_by_address)
	(sort_pst_symbols, partial_symtab::partial_symtab): Update.
	(concat): Remove.
	(end_psymtab_common): Simplify.
	(append_psymbol_to_list): Change parameters.
	(partial_symtabs::add_psymbol): Rename from add_psymbol_to_list.
	(init_psymbol_list): Simplify.
	(maintenance_info_psymtabs, maintenance_check_psymtabs): Update.
	* psympriv.h (struct partial_symtab) <empty>: New method.
	<globals_offset, n_global_syms, statics_offset, n_static_syms>:
	Remove.
	<global_psymbols, static_psymbols>: New members.
	<add_psymbol>: New methods.
	(add_psymbol_to_list): Don't declare.
	(psymbol_placement): Move earlier.
	* mdebugread.c (parse_partial_symbols): Update.
	(handle_psymbol_enumerators): Change parameters.
	(mdebug_expand_psymtab): Update.
	* dwarf2/read.c (process_psymtab_comp_unit_reader)
	(add_partial_symbol): Update.
	* dwarf2/index-write.c (write_psymbols): Change parameters.
	(write_one_signatured_type): Update.
	(recursively_count_psymbols): Update.
	(recursively_write_psymbols): Update.
	(class debug_names) <recursively_write_psymbols>: Update.
	<write_psymbols>: Change parameters.
	<write_one_signatured_type>: Update.
	* dbxread.c (read_dbx_symtab): Update.
	(dbx_end_psymtab): Use partial_symtab::empty.
	* ctfread.c (struct ctf_context) <pst>: New member.
	(create_partial_symtab): Set it.
	(ctf_psymtab_type_cb, ctf_psymtab_var_cb): Update.
	(scan_partial_symbols): Use the psymtab's context.  Update.