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[binutils-gdb] Use bitset for demangled_hash_languages
- From: Tom Tromey <tromey at sourceware dot org>
- To: gdb-cvs at sourceware dot org
- Date: 15 Mar 2019 22:07:52 -0000
- Subject: [binutils-gdb] Use bitset for demangled_hash_languages
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=1b7a07cba0aa096c2eb66895ef339aa5143e9995
commit 1b7a07cba0aa096c2eb66895ef339aa5143e9995
Author: Tom Tromey <tom@tromey.com>
Date: Fri Mar 1 19:55:46 2019 -0700
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.
Diff:
---
gdb/ChangeLog | 7 +++++++
gdb/minsyms.c | 18 +++++++++++-------
gdb/objfiles.h | 7 +++----
3 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2d6d895..867df17 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,12 @@
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>:
Don't return the symbol.
* coffread.c (record_minimal_symbol): Use record_full.
diff --git a/gdb/minsyms.c b/gdb/minsyms.c
index 0513cfe..cbb45f1 100644
--- a/gdb/minsyms.c
+++ b/gdb/minsyms.c
@@ -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);
diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index c5ce9ee..47df002 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -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