Use bitset for demangled_hash_languages

I noticed that objfile_per_bfd_storage::demangled_hash_languages is a
std::vector, which seemed quite large for something that,
fundamentally, can be represented as a bitset.  This patch
reimplements it as a std::bitset.

gdb/ChangeLog
2019-03-15  Tom Tromey  <tom@tromey.com>

	* objfiles.h (struct objfile_per_bfd_storage)
	<demangled_hash_languages>: Now a bitset.
	* minsyms.c (add_minsym_to_demangled_hash_table): Update.
	(lookup_minimal_symbol): Update.
This commit is contained in:
Tom Tromey 2019-03-01 19:55:46 -07:00
parent 3db066bcd5
commit 1b7a07cba0
3 changed files with 21 additions and 11 deletions

View File

@ -1,3 +1,10 @@
2019-03-15 Tom Tromey <tom@tromey.com>
* objfiles.h (struct objfile_per_bfd_storage)
<demangled_hash_languages>: Now a bitset.
* minsyms.c (add_minsym_to_demangled_hash_table): Update.
(lookup_minimal_symbol): Update.
2019-03-15 Tom Tromey <tom@tromey.com>
* minsyms.h (class minimal_symbol_reader) <record_with_info>:

View File

@ -160,11 +160,7 @@ add_minsym_to_demangled_hash_table (struct minimal_symbol *sym,
unsigned int hash = search_name_hash (MSYMBOL_LANGUAGE (sym),
MSYMBOL_SEARCH_NAME (sym));
auto &vec = objfile->per_bfd->demangled_hash_languages;
auto it = std::lower_bound (vec.begin (), vec.end (),
MSYMBOL_LANGUAGE (sym));
if (it == vec.end () || *it != MSYMBOL_LANGUAGE (sym))
vec.insert (it, MSYMBOL_LANGUAGE (sym));
objfile->per_bfd->demangled_hash_languages.set (MSYMBOL_LANGUAGE (sym));
struct minimal_symbol **table
= objfile->per_bfd->msymbol_demangled_hash;
@ -354,8 +350,12 @@ lookup_minimal_symbol (const char *name, const char *sfile,
{
/* Once for each language in the demangled hash names
table (usually just zero or one languages). */
for (auto lang : objfile->per_bfd->demangled_hash_languages)
for (unsigned iter = 0; iter < nr_languages; ++iter)
{
if (!objfile->per_bfd->demangled_hash_languages.test (iter))
continue;
enum language lang = (enum language) iter;
unsigned int hash
= (lookup_name.search_name_hash (lang)
% MINIMAL_SYMBOL_HASH_SIZE);
@ -497,8 +497,12 @@ iterate_over_minimal_symbols
/* The second pass is over the demangled table. Once for each
language in the demangled hash names table (usually just zero or
one). */
for (auto lang : objf->per_bfd->demangled_hash_languages)
for (unsigned liter = 0; liter < nr_languages; ++liter)
{
if (!objf->per_bfd->demangled_hash_languages.test (liter))
continue;
enum language lang = (enum language) liter;
const language_defn *lang_def = language_def (lang);
symbol_name_matcher_ftype *name_match
= get_symbol_name_matcher (lang_def, lookup_name);

View File

@ -28,6 +28,7 @@
#include "registry.h"
#include "gdb_bfd.h"
#include "psymtab.h"
#include <bitset>
#include <vector>
#include "common/next-iterator.h"
#include "common/safe-iterator.h"
@ -313,10 +314,8 @@ struct objfile_per_bfd_storage
minimal_symbol *msymbol_demangled_hash[MINIMAL_SYMBOL_HASH_SIZE] {};
/* All the different languages of symbols found in the demangled
hash table. A flat/vector-based map is more efficient than a map
or hash table here, since this will only usually contain zero or
one entries. */
std::vector<enum language> demangled_hash_languages;
hash table. */
std::bitset<nr_languages> demangled_hash_languages;
};
/* Master structure for keeping track of each file from which