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.

1 files changed, 42 insertions, 1 deletions

diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index 1f08b5a..14efd73 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -9,6 +9,7 @@ AUTOMAKE_OPTIONS =
 # The two_file_test tests -fmerge-constants, so we simply always turn
 # it on.  This may need to be controlled by a configure option
 # eventually.
+AM_CFLAGS = $(WARN_CFLAGS) $(LFS_CFLAGS) -fmerge-constants
 AM_CXXFLAGS = $(WARN_CXXFLAGS) $(LFS_CFLAGS) -fmerge-constants
 
 INCLUDES = \
@@ -22,6 +23,10 @@ TEST_OBJDUMP = $(top_builddir)/../binutils/objdump
 TEST_CXXFILT = $(top_builddir)/../binutils/cxxfilt
 TEST_STRIP = $(top_builddir)/../binutils/strip-new
 
+if PLUGINS
+LIBDL = -ldl
+endif
+
 if THREADS
 THREADSLIB = -lpthread
 endif
@@ -57,7 +62,7 @@ libgoldtest_a_SOURCES = test.cc testmain.cc testfile.cc
 DEPENDENCIES = \
 	libgoldtest.a ../libgold.a ../../libiberty/libiberty.a $(LIBINTL_DEP)
 LDADD = libgoldtest.a ../libgold.a ../../libiberty/libiberty.a $(LIBINTL) \
-	$(THREADSLIB)
+	$(THREADSLIB) $(LIBDL)
 
 
 # The unittests themselves
@@ -897,5 +902,41 @@ script_test_4: basic_test.o gcctestdir/ld $(srcdir)/script_test_4.t
 script_test_4.stdout: script_test_4
 	$(TEST_READELF) -SlW script_test_4 > script_test_4.stdout
 
+if PLUGINS
+
+check_PROGRAMS += plugin_test_1
+check_SCRIPTS += plugin_test_1.sh
+check_DATA += plugin_test_1.err
+MOSTLYCLEANFILES += plugin_test_1.err
+plugin_test_1: two_file_test_main.o two_file_test_1.syms two_file_test_1b.syms two_file_test_2.syms gcctestdir/ld plugin_test.so
+	$(CXXLINK) -Bgcctestdir/ -Wl,--no-demangle,--plugin,"./plugin_test.so;_Z4f13iv" two_file_test_main.o two_file_test_1.syms two_file_test_1b.syms two_file_test_2.syms 2>plugin_test_1.err
+plugin_test_1.err: plugin_test_1
+	@touch plugin_test_1.err
+
+check_PROGRAMS += plugin_test_2
+check_SCRIPTS += plugin_test_2.sh
+check_DATA += plugin_test_2.err
+MOSTLYCLEANFILES += plugin_test_2.err
+plugin_test_2: two_file_test_main.o two_file_test_1.syms two_file_test_1b.syms two_file_shared_2.so gcctestdir/ld plugin_test.so
+	$(CXXLINK) -Bgcctestdir/ -Wl,--no-demangle,-R,.,--plugin,"./plugin_test.so" two_file_test_main.o two_file_test_1.syms two_file_test_1b.syms two_file_shared_2.so 2>plugin_test_2.err
+plugin_test_2.err: plugin_test_2
+	@touch plugin_test_2.err
+
+plugin_test.so: plugin_test.o
+	$(LINK) -Bgcctestdir/ -shared plugin_test.o
+plugin_test.o: plugin_test.c
+	$(COMPILE) -O0 -c -fpic -o $@ $<
+
+two_file_test_main.syms: two_file_test_main.o
+	$(TEST_READELF) -sW $< >$@ 2>/dev/null
+two_file_test_1.syms: two_file_test_1.o
+	$(TEST_READELF) -sW $< >$@ 2>/dev/null
+two_file_test_1b.syms: two_file_test_1b.o
+	$(TEST_READELF) -sW $< >$@ 2>/dev/null
+two_file_test_2.syms: two_file_test_2.o
+	$(TEST_READELF) -sW $< >$@ 2>/dev/null
+
+endif PLUGINS
+
 endif GCC
 endif NATIVE_LINKER