libabigail/include/abg-corpus.h
Dodji Seketeli dc2f054d03 Build the set of exported decls directly during DWARF loading
Until now, after the ABI corpus was built from DWARF, the translation
units of the corpus were walked and each function was considered for
addition into the set of exported decls.  During that walking, a first
version of the set was put into a std::list and then, a set of filters
(user-provided tunables like a list of regular expressions to keep or
remove some functions from the exported decls) is applied to that list
and the final set of exported decls is put in a std::vector.

Profiling has shown that this process of building the set of exported
decls is a hot spot and also that the current use of std::list was a
big memory consumer especially on binaries with large exported symbol
tables.

So this patch builds the set of exported decls "on the fly", during
DWARF reading, as opposed to waiting after the DWARF is read and
having to walk the corpus again.  The corpus defines a policy object
that encapsulates the methods for determining if a function or
variable ought to be part of the set of exported decls.  The DWARF
reader uses that policy object to determine which functions and
variables among those built during the reading ought be part of the
exported decls; the policy object also has a reference to the final
vector (managed by the corpus) that must hold the exported decls, so
the decls are put in that vector directly without unnecessary copying.

Profiling also showed that the string copying done by
{var_decl,function_decl}::get_id() was a hot spot.  So the patch
returns a reference there.

With this patch applied, the peak memory consumption of abidiff on
libabigail.so itself (abidiff libabigail.so libabigail.so) is 54MB of
resident and takes 2 minutes and 16s (on my slow system).  Without the
patch the peak consumption was more than 300MB and it was taking
slightly longer.

For the test of bug
https://sourceware.org/bugzilla/show_bug.cgi?id=17948, memory
consumtion and wall clock time spent is down from 3.4GB and 1m59s to
760MB and 0m43s.

	* include/abg-ir.h ({var,function}_decl::get_id): Return a
	reference.
	* src/abg-ir.cc ({var,function}_decl::get_id): Return a reference
	to the string rather than copying it over.
	* include/abg-corpus.h (class corpus::exported_decls_builder):
	Declare new type.
	(corpus::{sort_functions, sort_variables,
	maybe_drop_some_exported_decls, get_exported_decls_builder}):
	Declare new methods.
	* src/abg-corpus.h (corpus::exported_decls_builder::priv): Define
	new type.
	(class symtab_build_visitor_type): Remove this type that is
	useless now.
	(corpus::exported_decls_builder::{exported_decls_builder,
	exported_functions, exported_variables,
	maybe_add_fn_to_exported_fns, maybe_add_var_to_exported_vars}):
	Define new functions.
	(corpus::priv::is_public_decl_table_built): Remove this data
	member.  It's now useless.
	(corpus::priv::priv): Adjust.
	(corpus::priv::build_public_decl_table): Remove this member
	function.  It's now useless.
	(corpus::{priv::build_unreferenced_symbols_tables, get_functions,
	get_variables}): No need to build the public decls table here.
	It's already built by the time the corpus is read from DWARF now.
	(corpus::{sort_functions, sort_variables,
	maybe_drop_some_exported_decls, get_exported_decls_builder}):
	Define new member functions.
	* src/abg-dwarf-reader.cc (read_context::exported_decls_builder):
	New data member.
	(read_context::read_context): Initialize it.
	(read_context::{exported_decls_builder,
	maybe_add_fn_to_exported_fns, maybe_add_var_to_exported_vars}):
	Define new member functions.
	(read_debug_info_into_corpus): Get the the new
	'exported_decls_builder' object from the corpus and stick it into
	the read context so the DWARF reading code can use it to build the
	exported decls set.  When the DWARF reading is done, sort the set
	of exported functions and variables that was built.
	(build_ir_node_from_die): When a function or variable is built,
	consider putting it into the set of exported decls.
	* tools/abicompat.cc (main): Now that the exported decls is built
	*before* we had a chance to stick the list of symbol IDs to keep,
	call corpus::maybe_drop_some_exported_decls() to update the set of
	exported decls we should consider for the corpus.

was applied to that list and the final

Signed-off-by: Dodji Seketeli <dodji@redhat.com>
2015-02-24 13:15:10 +01:00

313 lines
7.0 KiB
C++

// -*- mode: C++ -*-
//
// Copyright (C) 2013-2015 Red Hat, Inc.
//
// This file is part of the GNU Application Binary Interface Generic
// Analysis and Instrumentation Library (libabigail). This library is
// free software; you can redistribute it and/or modify it under the
// terms of the GNU Lesser General Public License as published by the
// Free Software Foundation; either version 3, or (at your option) any
// later version.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Lesser Public License for more details.
// You should have received a copy of the GNU Lesser General Public
// License along with this program; see the file COPYING-LGPLV3. If
// not, see <http://www.gnu.org/licenses/>.
/// @file
#ifndef __ABG_CORPUS_H__
#define __ABG_CORPUS_H__
#include <abg-ir.h>
namespace abigail
{
namespace ir
{
class corpus;
/// A convenience typedef for shared pointer to @ref corpus.
typedef shared_ptr<corpus> corpus_sptr;
/// This is the abstraction of a set of translation units (themselves
/// seen as bundles of unitary abi artefacts like types and decls)
/// bundled together as a corpus. A corpus is thus the Application
/// binary interface of a program, a library or just a set of modules
/// put together.
class corpus
{
public:
struct priv;
/// Convenience typedef for shared_ptr of corpus::priv
typedef shared_ptr<priv> priv_sptr;
/// A convenience typedef for std::vector<string>.
typedef vector<string> strings_type;
/// Convenience typedef for std::vector<abigail::ir::function_decl*>
typedef vector<function_decl*> functions;
///Convenience typedef for std::vector<abigail::ir::var_decl*>
typedef vector<var_decl*> variables;
class exported_decls_builder;
/// Convenience typedef for shared_ptr<exported_decls_builder>.
typedef shared_ptr<exported_decls_builder> exported_decls_builder_sptr;
/// This abstracts where the corpus comes from. That is, either it
/// has been read from the native xml format, from DWARF or built
/// artificially using the library's API.
enum origin
{
ARTIFICIAL_ORIGIN = 0,
NATIVE_XML_ORIGIN,
DWARF_ORIGIN
};
private:
shared_ptr<priv> priv_;
corpus();
public:
corpus(const string&);
void
add(const translation_unit_sptr);
const translation_units&
get_translation_units() const;
void
drop_translation_units();
origin
get_origin() const;
void
set_origin(origin);
string&
get_path() const;
void
set_path(const string&);
const vector<string>&
get_needed() const;
void
set_needed(const vector<string>&);
const string&
get_soname();
void
set_soname(const string&);
const string&
get_architecture_name();
void
set_architecture_name(const string&);
bool
is_empty() const;
bool
operator==(const corpus&) const;
void
set_fun_symbol_map(string_elf_symbols_map_sptr);
void
set_undefined_fun_symbol_map(string_elf_symbols_map_sptr);
void
set_var_symbol_map(string_elf_symbols_map_sptr);
void
set_undefined_var_symbol_map(string_elf_symbols_map_sptr);
const string_elf_symbols_map_sptr
get_fun_symbol_map_sptr() const;
const string_elf_symbols_map_type&
get_fun_symbol_map() const;
const string_elf_symbols_map_sptr
get_undefined_fun_symbol_map_sptr() const;
const string_elf_symbols_map_type&
get_undefined_fun_symbol_map() const;
const elf_symbols&
get_sorted_fun_symbols() const;
const elf_symbols&
get_sorted_undefined_fun_symbols() const;
const string_elf_symbols_map_sptr
get_var_symbol_map_sptr() const;
const string_elf_symbols_map_type&
get_var_symbol_map() const;
const string_elf_symbols_map_sptr
get_undefined_var_symbol_map_sptr() const;
const string_elf_symbols_map_type&
get_undefined_var_symbol_map() const;
const elf_symbols&
get_sorted_var_symbols() const;
const elf_symbols&
get_sorted_undefined_var_symbols() const;
const elf_symbol_sptr
lookup_function_symbol(const string& n) const;
const elf_symbol_sptr
lookup_function_symbol(const string& symbol_name,
const string& symbol_version) const;
const elf_symbol_sptr
lookup_variable_symbol(const string& n) const;
const elf_symbol_sptr
lookup_variable_symbol(const string& symbol_name,
const string& symbol_version) const;
const functions&
get_functions() const;
void
sort_functions();
const variables&
get_variables() const;
void
sort_variables();
const elf_symbols&
get_unreferenced_function_symbols() const;
const elf_symbols&
get_unreferenced_variable_symbols() const;
vector<string>&
get_regex_patterns_of_fns_to_suppress();
const vector<string>&
get_regex_patterns_of_fns_to_suppress() const;
vector<string>&
get_regex_patterns_of_vars_to_suppress();
const vector<string>&
get_regex_patterns_of_vars_to_suppress() const;
vector<string>&
get_regex_patterns_of_fns_to_keep();
const vector<string>&
get_regex_patterns_of_fns_to_keep() const;
vector<string>&
get_sym_ids_of_fns_to_keep();
const vector<string>&
get_sym_ids_of_fns_to_keep() const;
vector<string>&
get_regex_patterns_of_vars_to_keep();
const vector<string>&
get_regex_patterns_of_vars_to_keep() const;
vector<string>&
get_sym_ids_of_vars_to_keep();
const vector<string>&
get_sym_ids_of_vars_to_keep() const;
void
maybe_drop_some_exported_decls();
exported_decls_builder_sptr
get_exported_decls_builder() const;
};// end class corpus.
/// Abstracts the building of the set of exported variables and
/// functions.
///
/// Given a function or variable, this type can decide if it belongs
/// to the list of exported functions and variables based on all the
/// parameters needed.
class corpus::exported_decls_builder
{
public:
class priv;
/// Convenience typedef for shared_ptr<priv>
typedef shared_ptr<priv> priv_sptr;
/// Convenience typedef for a hash map which key is a string an
/// which data is an abigail::ir::function_decl*
typedef unordered_map<string, function_decl*> str_fn_ptr_map_type;
/// Convenience typedef for a hash map which key is a string and
/// which data is an abigail::ir::var_decl*.
typedef unordered_map<string, var_decl*> str_var_ptr_map_type;
friend class corpus;
private:
priv_sptr priv_;
// Forbid default construction.
exported_decls_builder();
public:
exported_decls_builder(functions& fns,
variables& vars,
strings_type& fns_suppress_regexps,
strings_type& vars_suppress_regexps,
strings_type& fns_keep_regexps,
strings_type& vars_keep_regexps,
strings_type& sym_id_of_fns_to_keep,
strings_type& sym_id_of_vars_to_keep);
const functions&
exported_functions() const;
functions&
exported_functions();
const variables&
exported_variables() const;
variables&
exported_variables();
void
maybe_add_fn_to_exported_fns(function_decl*);
void
maybe_add_var_to_exported_vars(var_decl*);
}; //corpus::exported_decls_builder
}// end namespace ir
}//end namespace abigail
#endif //__ABG_CORPUS_H__