Add plugin functionality for link-time optimization (LTO).

include/:
	* plugin-api.h: New file.

gold/:
	* configure.ac (plugins): Add --enable-plugins option.
	* configure: Regenerate.
	* config.in: Regenerate.
	* Makefile.am (LIBDL): New variable.
	(CCFILES): Add plugin.cc.
	(HFILES): Add plugin.h.
	(ldadd_var): Add LIBDL.
	* Makefile.in: Regenerate.

	* archive.cc: Include "plugin.h".
	(Archive::setup): Don't preread archive symbols when using a plugin.
	(Archive::get_file_and_offset): Add memsize parameter.  Change callers.
	(Archive::get_elf_object_for_member): Call plugin hooks for claiming
	files.
	(Archive::include_member): Add symbols from plugin objects.
	* archive.h (Archive::get_file_and_offset): Add memsize parameter.
	* descriptors.cc (Descriptors::open): Check for file descriptors
	abandoned by plugins.
	(Descriptors::claim_for_plugin): New function.
	* descriptors.h (Descriptors::claim_for_plugin): New function.
	(Open_descriptor::is_claimed): New field.
	(claim_descriptor_for_plugin): New function.
	* fileread.cc (File_read::claim_for_plugin): New function.
	* fileread.h (File_read::claim_for_plugin): New function.
	(File_read::descriptor): New function.
	* gold.cc: Include "plugin.h".
	(queue_initial_tasks): Add task to call plugin hooks for generating
	new object files.
	* main.cc: Include "plugin.h".
	(main): Load plugin libraries.
	* object.h (Pluginobj): Declare.
	(Object::pluginobj): New function.
	(Object::do_pluginobj): New function.
	(Object::set_target): New function.
	* options.cc: Include "plugin.h".
	(General_options::parse_plugin): New function.
	(General_options::General_options): Initialize plugins_ field.
	(General_options::add_plugin): New function.
	* options.h (Plugin_manager): Declare.
	(General_options): Add --plugin option.
	(General_options::has_plugins): New function.
	(General_options::plugins): New function.
	(General_options::add_plugin): New function.
	(General_options::plugins_): New field.
	* plugin.cc: New file.
	* plugin.h: New file.
	* readsyms.cc: Include "plugin.h".
	(Read_symbols::do_read_symbols): Check for archive before checking
	for ELF file.  Call plugin hooks to claim files.
	* resolve.cc (Symbol_table::resolve): Record when symbol is referenced
	from a real object file; force override when processing replacement
	files.
	* symtab.cc (Symbol::init_fields): Initialize in_real_elf_ field.
	(Symbol::init_base_object): Likewise.
	(Symbol::init_base_output_data): Likewise.
	(Symbol::init_base_output_segment): Likewise.
	(Symbol::init_base_constant): Likewise.
	(Symbol::init_base_undefined): Likewise.
	(Symbol::output_section): Assert that object is not a plugin.
	(Symbol_table::add_from_pluginobj): New function.
	(Symbol_table::sized_finalize_symbol): Treat symbols from plugins as
	undefined.
	(Symbol_table::sized_write_globals): Likewise.
	(Symbol_table::add_from_pluginobj): Instantiate template.
	* symtab.h (Sized_pluginobj): Declare.
	(Symbol::in_real_elf): New function.
	(Symbol::set_in_real_elf): New function.
	(Symbol::in_real_elf_): New field.
	(Symbol_table::add_from_pluginobj): New function.

	* testsuite/Makefile.am (AM_CFLAGS): New variable.
	(LIBDL): New variable.
	(LDADD): Add LIBDL.
	(check_PROGRAMS): Add plugin_test_1 and plugin_test_2.
	(check_SCRIPTS): Add plugin_test_1.sh and plugin_test_2.sh.
	(check_DATA): Add plugin_test_1.err and plugin_test_2.err.
	(MOSTLYCLEANFILES): Likewise.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/plugin_test.c: New file.
	* testsuite/plugin_test_1.sh: New file.
	* testsuite/plugin_test_2.sh: New file.
This commit is contained in:
Cary Coutant 2008-09-19 22:54:57 +00:00
parent acf5111a6f
commit 1d1c001cb4
2 changed files with 247 additions and 0 deletions

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@ -1,3 +1,8 @@
2008-09-18 Cary Coutant <ccoutant@google.com>
Add plugin functionality for link-time optimization (LTO).
* plugin-api.h: New file.
2008-09-09 Jason Merrill <jason@redhat.com>
* demangle.h (enum demangle_component_type): Add

242
include/plugin-api.h Normal file
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@ -0,0 +1,242 @@
/* plugin-api.h -- External linker plugin API. */
/* Copyright 2008 Free Software Foundation, Inc.
Written by Cary Coutant <ccoutant@google.com>.
This file is part of binutils.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
/* This file defines the interface for writing a linker plugin, which is
described at < http://gcc.gnu.org/wiki/whopr/driver >. */
#ifndef PLUGIN_API_H
#define PLUGIN_API_H
#include <stdint.h>
#include <sys/types.h>
#ifdef __cplusplus
extern "C"
{
#endif
/* Status code returned by most API routines. */
enum ld_plugin_status
{
LDPS_OK = 0,
LDPS_NO_SYMS, // Attempt to get symbols that haven't been added.
LDPS_ERR,
/* Additional Error codes TBD. */
};
/* The version of the API specification. */
enum ld_plugin_api_version
{
LD_PLUGIN_API_VERSION = 1,
};
/* The type of output file being generated by the linker. */
enum ld_plugin_output_file_type
{
LDPO_REL,
LDPO_EXEC,
LDPO_DYN,
};
/* An input file managed by the plugin library. */
struct ld_plugin_input_file
{
const char *name;
int fd;
off_t offset;
off_t filesize;
void *handle;
};
/* A symbol belonging to an input file managed by the plugin library. */
struct ld_plugin_symbol
{
char *name;
char *version;
int def;
int visibility;
uint64_t size;
char *comdat_key;
int resolution;
};
/* Whether the symbol is a definition, reference, or common, weak or not. */
enum ld_plugin_symbol_kind
{
LDPK_DEF,
LDPK_WEAKDEF,
LDPK_UNDEF,
LDPK_WEAKUNDEF,
LDPK_COMMON,
};
/* The visibility of the symbol. */
enum ld_plugin_symbol_visibility
{
LDPV_DEFAULT,
LDPV_PROTECTED,
LDPV_INTERNAL,
LDPV_HIDDEN,
};
/* How a symbol is resolved. */
enum ld_plugin_symbol_resolution
{
LDPR_UNKNOWN = 0,
LDPR_UNDEF,
LDPR_PREVAILING_DEF,
LDPR_PREVAILING_DEF_IRONLY,
LDPR_PREEMPTED_REG,
LDPR_PREEMPTED_IR,
LDPR_RESOLVED_IR,
LDPR_RESOLVED_EXEC,
LDPR_RESOLVED_DYN,
};
/* The plugin library's "claim file" handler. */
typedef
enum ld_plugin_status
(*ld_plugin_claim_file_handler) (
const struct ld_plugin_input_file *file, int *claimed);
/* The plugin library's "all symbols read" handler. */
typedef
enum ld_plugin_status
(*ld_plugin_all_symbols_read_handler) (void);
/* The plugin library's cleanup handler. */
typedef
enum ld_plugin_status
(*ld_plugin_cleanup_handler) (void);
/* The linker's interface for registering the "claim file" handler. */
typedef
enum ld_plugin_status
(*ld_plugin_register_claim_file) (ld_plugin_claim_file_handler handler);
/* The linker's interface for registering the "all symbols read" handler. */
typedef
enum ld_plugin_status
(*ld_plugin_register_all_symbols_read) (
ld_plugin_all_symbols_read_handler handler);
/* The linker's interface for registering the cleanup handler. */
typedef
enum ld_plugin_status
(*ld_plugin_register_cleanup) (ld_plugin_cleanup_handler handler);
/* The linker's interface for adding symbols from a claimed input file. */
typedef
enum ld_plugin_status
(*ld_plugin_add_symbols) (void *handle, int nsyms,
const struct ld_plugin_symbol *syms);
/* The linker's interface for retrieving symbol resolution information. */
typedef
enum ld_plugin_status
(*ld_plugin_get_symbols) (const void *handle, int nsyms,
struct ld_plugin_symbol *syms);
/* The linker's interface for adding a compiled input file. */
typedef
enum ld_plugin_status
(*ld_plugin_add_input_file) (char *pathname);
/* The linker's interface for issuing a warning or error message. */
typedef
enum ld_plugin_status
(*ld_plugin_message) (int level, char *format, ...);
enum ld_plugin_level
{
LDPL_INFO,
LDPL_WARNING,
LDPL_ERROR,
LDPL_FATAL,
};
/* Values for the tv_tag field of the transfer vector. */
enum ld_plugin_tag
{
LDPT_NULL = 0,
LDPT_API_VERSION,
LDPT_GOLD_VERSION,
LDPT_LINKER_OUTPUT,
LDPT_OPTION,
LDPT_REGISTER_CLAIM_FILE_HOOK,
LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK,
LDPT_REGISTER_CLEANUP_HOOK,
LDPT_ADD_SYMBOLS,
LDPT_GET_SYMBOLS,
LDPT_ADD_INPUT_FILE,
LDPT_MESSAGE,
};
/* The plugin transfer vector. */
struct ld_plugin_tv
{
enum ld_plugin_tag tv_tag;
union
{
int tv_val;
const char *tv_string;
ld_plugin_register_claim_file tv_register_claim_file;
ld_plugin_register_all_symbols_read tv_register_all_symbols_read;
ld_plugin_register_cleanup tv_register_cleanup;
ld_plugin_add_symbols tv_add_symbols;
ld_plugin_get_symbols tv_get_symbols;
ld_plugin_add_input_file tv_add_input_file;
ld_plugin_message tv_message;
} tv_u;
};
/* The plugin library's "onload" entry point. */
typedef
enum ld_plugin_status
(*ld_plugin_onload) (struct ld_plugin_tv *tv);
#ifdef __cplusplus
};
#endif
#endif /* !defined(PLUGIN_API_H) */