FreeChainXenon/binutils-gdb
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Introduce objfile::intern

Browse source 
This introduces a string cache on the per-BFD object, replacing the
macro and filename caches.  Both of these caches just store strings,
so this consolidation by itself saves a little memory (about the size
of a bcache per objfile).

Then this patch switches some allocations on the objfile obstack to
use this bcache instead.  This saves more space; and turns out to be a
bit faster as well.

Here are the before and after "maint time" + "maint space" results of
"file ./gdb":

    Command execution time: 4.664021 (cpu), 4.728518 (wall)
    Space used: 39190528 (+29212672 for this command)

    Command execution time: 4.216209 (cpu), 4.107023 (wall)
    Space used: 36667392 (+26689536 for this command)

The main interface to the string cache is a new pair of overloaded
methods, objfile::intern.

gdb/ChangeLog
2020-03-04  Tom Tromey  <tom@tromey.com>

	* symmisc.c (print_symbol_bcache_statistics)
	(print_objfile_statistics): Update.
	* symfile.c (allocate_symtab): Use intern.
	* psymtab.c (partial_symtab::partial_symtab): Use intern.
	* objfiles.h (struct objfile_per_bfd_storage) <filename_cache,
	macro_cache>: Remove.
	<string_cache>: New member.
	(struct objfile) <intern>: New methods.
	* elfread.c (elf_symtab_read): Use intern.
	* dwarf2/read.c (fixup_go_packaging): Intern package name.
	(dwarf2_compute_name, dwarf2_physname)
	(create_dwo_unit_in_dwp_v1, create_dwo_unit_in_dwp_v2): Intern
	names.
	(guess_partial_die_structure_name): Update.
	(partial_die_info::fixup): Intern name.
	(dwarf2_canonicalize_name): Change parameter to objfile.  Intern
	name.
	(dwarf2_name): Intern name.  Update.
	* buildsym.c (buildsym_compunit::get_macro_table): Use
	string_cache.
This commit is contained in:
Tom Tromey 2020-03-04 16:34:49 -07:00
parent 4e7625fde2
commit be1e3d3eab
8 changed files with 64 additions and 52 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
gdb/ChangeLog
View file

@ -1,3 +1,26 @@
2020-03-04 Tom Tromey <tom@tromey.com>
* symmisc.c (print_symbol_bcache_statistics)
(print_objfile_statistics): Update.
* symfile.c (allocate_symtab): Use intern.
* psymtab.c (partial_symtab::partial_symtab): Use intern.
* objfiles.h (struct objfile_per_bfd_storage) <filename_cache,
macro_cache>: Remove.
<string_cache>: New member.
(struct objfile) <intern>: New methods.
* elfread.c (elf_symtab_read): Use intern.
* dwarf2/read.c (fixup_go_packaging): Intern package name.
(dwarf2_compute_name, dwarf2_physname)
(create_dwo_unit_in_dwp_v1, create_dwo_unit_in_dwp_v2): Intern
names.
(guess_partial_die_structure_name): Update.
(partial_die_info::fixup): Intern name.
(dwarf2_canonicalize_name): Change parameter to objfile. Intern
name.
(dwarf2_name): Intern name. Update.
* buildsym.c (buildsym_compunit::get_macro_table): Use
string_cache.
2020-03-04 Tom Tromey <tom@tromey.com>
* jit.c (bfd_open_from_target_memory): Make "target" const.

2
gdb/buildsym.c
View file

@ -120,7 +120,7 @@ buildsym_compunit::get_macro_table ()
{
if (m_pending_macros == nullptr)
m_pending_macros = new_macro_table (&m_objfile->per_bfd->storage_obstack,
&m_objfile->per_bfd->macro_cache,
&m_objfile->per_bfd->string_cache,
m_compunit_symtab);
return m_pending_macros;
}

43
gdb/dwarf2/read.c
View file

@ -1447,7 +1447,7 @@ static const gdb_byte *read_full_die (const struct die_reader_specs *,
static void process_die (struct die_info *, struct dwarf2_cu *);
static const char *dwarf2_canonicalize_name (const char *, struct dwarf2_cu *,
struct obstack *);
struct objfile *);
static const char *dwarf2_name (struct die_info *die, struct dwarf2_cu *);
@ -9098,8 +9098,7 @@ fixup_go_packaging (struct dwarf2_cu *cu)
if (package_name != NULL)
{
struct objfile *objfile = cu->per_cu->dwarf2_per_objfile->objfile;
const char *saved_package_name
= obstack_strdup (&objfile->per_bfd->storage_obstack, package_name.get ());
const char *saved_package_name = objfile->intern (package_name.get ());
struct type *type = init_type (objfile, TYPE_CODE_MODULE, 0,
saved_package_name);
struct symbol *sym;
@ -10225,14 +10224,13 @@ dwarf2_compute_name (const char *name,
if (cu->language == language_cplus)
canonical_name
= dwarf2_canonicalize_name (intermediate_name.c_str (), cu,
&objfile->per_bfd->storage_obstack);
objfile);
/* If we only computed INTERMEDIATE_NAME, or if
INTERMEDIATE_NAME is already canonical, then we need to
copy it to the appropriate obstack. */
intern it. */
if (canonical_name == NULL || canonical_name == intermediate_name.c_str ())
name = obstack_strdup (&objfile->per_bfd->storage_obstack,
intermediate_name);
name = objfile->intern (intermediate_name);
else
name = canonical_name;
}
@ -10352,7 +10350,7 @@ dwarf2_physname (const char *name, struct die_info *die, struct dwarf2_cu *cu)
retval = canon;
if (need_copy)
retval = obstack_strdup (&objfile->per_bfd->storage_obstack, retval);
retval = objfile->intern (retval);
return retval;
}
@ -11678,8 +11676,7 @@ create_dwo_unit_in_dwp_v1 (struct dwarf2_per_objfile *dwarf2_per_objfile,
virtual_dwo_name.c_str ());
}
dwo_file = new struct dwo_file;
dwo_file->dwo_name = obstack_strdup (&objfile->objfile_obstack,
virtual_dwo_name);
dwo_file->dwo_name = objfile->intern (virtual_dwo_name);
dwo_file->comp_dir = comp_dir;
dwo_file->sections.abbrev = sections.abbrev;
dwo_file->sections.line = sections.line;
@ -11874,8 +11871,7 @@ create_dwo_unit_in_dwp_v2 (struct dwarf2_per_objfile *dwarf2_per_objfile,
virtual_dwo_name.c_str ());
}
dwo_file = new struct dwo_file;
dwo_file->dwo_name = obstack_strdup (&objfile->objfile_obstack,
virtual_dwo_name);
dwo_file->dwo_name = objfile->intern (virtual_dwo_name);
dwo_file->comp_dir = comp_dir;
dwo_file->sections.abbrev =
create_dwp_v2_section (dwarf2_per_objfile, &dwp_file->sections.abbrev,
@ -17993,8 +17989,7 @@ partial_die_info::read (const struct die_reader_specs *reader,
struct objfile *objfile = dwarf2_per_objfile->objfile;
name
= dwarf2_canonicalize_name (DW_STRING (&attr), cu,
&objfile->per_bfd->storage_obstack);
= dwarf2_canonicalize_name (DW_STRING (&attr), cu, objfile);
}
break;
}
@ -18319,9 +18314,7 @@ guess_partial_die_structure_name (struct partial_die_info *struct_pdi,
if (actual_class_name != NULL)
{
struct objfile *objfile = cu->per_cu->dwarf2_per_objfile->objfile;
struct_pdi->name
= obstack_strdup (&objfile->per_bfd->storage_obstack,
actual_class_name.get ());
struct_pdi->name = objfile->intern (actual_class_name.get ());
}
break;
}
@ -18401,7 +18394,7 @@ partial_die_info::fixup (struct dwarf2_cu *cu)
base = demangled.get ();
struct objfile *objfile = cu->per_cu->dwarf2_per_objfile->objfile;
name = obstack_strdup (&objfile->per_bfd->storage_obstack, base);
name = objfile->intern (base);
}
}
@ -21714,7 +21707,7 @@ sibling_die (struct die_info *die)
static const char *
dwarf2_canonicalize_name (const char *name, struct dwarf2_cu *cu,
struct obstack *obstack)
struct objfile *objfile)
{
if (name && cu->language == language_cplus)
{
@ -21723,7 +21716,7 @@ dwarf2_canonicalize_name (const char *name, struct dwarf2_cu *cu,
if (!canon_name.empty ())
{
if (canon_name != name)
name = obstack_strdup (obstack, canon_name);
name = objfile->intern (canon_name);
}
}
@ -21797,10 +21790,7 @@ dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
const char *base;
/* FIXME: we already did this for the partial symbol... */
DW_STRING (attr)
= obstack_strdup (&objfile->per_bfd->storage_obstack,
demangled.get ());
DW_STRING (attr) = objfile->intern (demangled.get ());
DW_STRING_IS_CANONICAL (attr) = 1;
/* Strip any leading namespaces/classes, keep only the base name.
@ -21820,9 +21810,8 @@ dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
if (!DW_STRING_IS_CANONICAL (attr))
{
DW_STRING (attr)
= dwarf2_canonicalize_name (DW_STRING (attr), cu,
&objfile->per_bfd->storage_obstack);
DW_STRING (attr) = dwarf2_canonicalize_name (DW_STRING (attr), cu,
objfile);
DW_STRING_IS_CANONICAL (attr) = 1;
}
return DW_STRING (attr);

6
gdb/elfread.c
View file

@ -355,11 +355,7 @@ elf_symtab_read (minimal_symbol_reader &reader,
if (type == ST_DYNAMIC && !stripped)
continue;
if (sym->flags & BSF_FILE)
{
filesymname
= ((const char *) objfile->per_bfd->filename_cache.insert
(sym->name, strlen (sym->name) + 1));
}
filesymname = objfile->intern (sym->name);
else if (sym->flags & BSF_SECTION_SYM)
continue;
else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK

24
gdb/objfiles.h
View file

@ -275,13 +275,9 @@ struct objfile_per_bfd_storage
auto_obstack storage_obstack;
/* Byte cache for file names. */
/* String cache. */
gdb::bcache filename_cache;
/* Byte cache for macros. */
gdb::bcache macro_cache;
gdb::bcache string_cache;
/* The gdbarch associated with the BFD. Note that this gdbarch is
determined solely from BFD information, without looking at target
@ -533,6 +529,22 @@ public:
return section_offsets[SECT_OFF_DATA (this)];
}
/* Intern STRING and return the unique copy. The copy has the same
lifetime as the per-BFD object. */
const char *intern (const char *str)
{
return (const char *) per_bfd->string_cache.insert (str, strlen (str) + 1);
}
/* Intern STRING and return the unique copy. The copy has the same
lifetime as the per-BFD object. */
const char *intern (const std::string &str)
{
return (const char *) per_bfd->string_cache.insert (str.c_str (),
str.size () + 1);
}
/* The object file's original name as specified by the user,
made absolute, and tilde-expanded. However, it is not canonicalized
(i.e., it has not been passed through gdb_realpath).

4
gdb/psymtab.c
View file

@ -1656,9 +1656,7 @@ partial_symtab::partial_symtab (const char *filename_, struct objfile *objfile)
{
objfile->partial_symtabs->install_psymtab (this);
filename
= ((const char *) objfile->per_bfd->filename_cache.insert
(filename_, strlen (filename_) + 1));
filename = objfile->intern (filename_);
if (symtab_create_debug)
{

4
gdb/symfile.c
View file

@ -2783,9 +2783,7 @@ allocate_symtab (struct compunit_symtab *cust, const char *filename)
struct symtab *symtab
= OBSTACK_ZALLOC (&objfile->objfile_obstack, struct symtab);
symtab->filename
= ((const char *) objfile->per_bfd->filename_cache.insert
(filename, strlen (filename) + 1));
symtab->filename = objfile->intern (filename);
symtab->fullname = NULL;
symtab->language = deduce_language_from_filename (filename);

10
gdb/symmisc.c
View file

@ -71,9 +71,7 @@ print_symbol_bcache_statistics (void)
objfile_name (objfile));
objfile->partial_symtabs->psymbol_cache.print_statistics
("partial symbol cache");
objfile->per_bfd->macro_cache.print_statistics
("preprocessor macro cache");
objfile->per_bfd->filename_cache.print_statistics ("file name cache");
objfile->per_bfd->string_cache.print_statistics ("string cache");
}
}
@ -135,10 +133,8 @@ print_objfile_statistics (void)
printf_filtered
(_(" Total memory used for psymbol cache: %d\n"),
objfile->partial_symtabs->psymbol_cache.memory_used ());
printf_filtered (_(" Total memory used for macro cache: %d\n"),
objfile->per_bfd->macro_cache.memory_used ());
printf_filtered (_(" Total memory used for file name cache: %d\n"),
objfile->per_bfd->filename_cache.memory_used ());
printf_filtered (_(" Total memory used for string cache: %d\n"),
objfile->per_bfd->string_cache.memory_used ());
}
}