Introduce RTL function reader

Introduce RTL function reader

This is the combination of these patches:
- [8a/9] Introduce class function_reader (v8)
- Add ASSERT_RTX_PTR_EQ
- [8b/9] Add target-independent selftests of RTL function reader (v2)
- [8c/9] Add aarch64-specific selftests for RTL function reader (v2)
- [8d/9] Add x86_64-specific selftests for RTL function reader (v2)

gcc/ChangeLog:
	* Makefile.in (OBJS): Add read-md.o, read-rtl.o,
	read-rtl-function.o, and selftest-rtl.o.
	* config/aarch64/aarch64.c: Include selftest.h and
	selftest-rtl.h.
	(selftest::aarch64_test_loading_full_dump): New function.
	(selftest::aarch64_run_selftests): New function.
	(TARGET_RUN_TARGET_SELFTESTS): Wire it up to
	selftest::aarch64_run_selftests.
	* config/i386/i386.c
	(selftest::ix86_test_loading_dump_fragment_1): New function.
	(selftest::ix86_test_loading_call_insn): New function.
	(selftest::ix86_test_loading_full_dump): New function.
	(selftest::ix86_test_loading_unspec): New function.
	(selftest::ix86_run_selftests): Call the new functions.
	* emit-rtl.c (maybe_set_max_label_num): New function.
	* emit-rtl.h (maybe_set_max_label_num): New decl.
	* function.c (instantiate_decls): Guard call to
	instantiate_decls_1 with if (DECL_INITIAL (fndecl)).
	* function-tests.c (selftest::verify_three_block_rtl_cfg): Remove
	"static".
	* gensupport.c (gen_reader::gen_reader): Pass "false"
	for new "compact" param of rtx_reader.
	* print-rtl.c (rtx_writer::print_rtx_operand): Print "(nil)"
	rather than an empty string for NULL strings.
	* read-md.c: Potentially include config.h rather than bconfig.h.
	Wrap include of errors.h with #ifdef GENERATOR_FILE.
	(have_error): New global, copied from errors.c.
	(md_reader::read_name): Rename to...
	(md_reader::read_name_1): ...this, adding "out_loc" param,
	and converting "missing name or number" to returning false, rather
	than failing.
	(md_reader::read_name): Reimplement in terms of read_name_1.
	(md_reader::read_name_or_nil): New function.
	(md_reader::read_string): Handle "(nil)" by returning NULL.
	(md_reader::md_reader): Add new param "compact".
	(md_reader::read_md_files): Wrap with #ifdef GENERATOR_FILE.
	(md_reader::read_file): New method.
	* read-md.h (md_reader::md_reader): Add new param "compact".
	(md_reader::read_file): New method.
	(md_reader::is_compact): New accessor.
	(md_reader::read_name): Convert return type from void to
	file_location.
	(md_reader::read_name_or_nil): New decl.
	(md_reader::read_name_1): New decl.
	(md_reader::m_compact): New field.
	(noop_reader::noop_reader): Pass "false" for new "compact" param
	of rtx_reader.
	(rtx_reader::rtx_reader): Add new "compact" param.
	(rtx_reader::read_rtx_operand): Make virtual and convert return
	type from void to rtx.
	(rtx_reader::read_until): New decl.
	(rtx_reader::handle_any_trailing_information): New virtual
	function.
	(rtx_reader::postprocess): New virtual function.
	(rtx_reader::finalize_string): New virtual function.
	(rtx_reader::m_in_call_function_usage): New field.
	(rtx_reader::m_reuse_rtx_by_id): New field.
	* read-rtl-function.c: New file.
	* selftest-rtl.c (selftest::assert_rtx_ptr_eq_at): New function.
	* selftest-rtl.h (ASSERT_RTX_PTR_EQ): New macro.
	(selftest::verify_three_block_rtl_cfg): New decl.
	* read-rtl-function.h: New file.
	* read-rtl.c: Potentially include config.h rather than bconfig.h.
	For host, include function.h, memmodel.h, and emit-rtl.h.
	(one_time_initialization): New function.
	(struct compact_insn_name): New struct.
	(compact_insn_names): New array.
	(find_code): Handle insn codes in compact dumps.
	(apply_subst_iterator): Wrap with #ifdef GENERATOR_FILE.
	(bind_subst_iter_and_attr): Likewise.
	(add_condition_to_string): Likewise.
	(add_condition_to_rtx): Likewise.
	(apply_attribute_uses): Likewise.
	(add_current_iterators): Likewise.
	(apply_iterators): Likewise.
	(initialize_iterators): Guard usage of apply_subst_iterator with
	#ifdef GENERATOR_FILE.
	(read_conditions): Wrap with #ifdef GENERATOR_FILE.
	(md_reader::read_mapping): Likewise.
	(add_define_attr_for_define_subst): Likewise.
	(add_define_subst_attr): Likewise.
	(read_subst_mapping): Likewise.
	(check_code_iterator): Likewise.
	(rtx_reader::read_rtx): Likewise.  Move one-time initialization
	logic to...
	(one_time_initialization): New function.
	(rtx_reader::read_until): New method.
	(read_flags): New function.
	(parse_reg_note_name): New function.
	(rtx_reader::read_rtx_code): Initialize "iterator" to NULL.
	Handle reuse_rtx ids.
	Wrap iterator lookup within #ifdef GENERATOR_FILE.
	Add parsing support for RTL dumps, mirroring the special-cases in
	print_rtx, by calling read_flags, reading REG_NOTE names, INSN_UID
	values, and calling handle_any_trailing_information.
	(rtx_reader::read_rtx_operand): Convert return type from void
	to rtx, returning return_rtx.  Handle case 'e'.  Call
	finalize_string on XSTR and XTMPL fields.
	(rtx_reader::read_nested_rtx):  Handle dumps in which trailing
	 "(nil)" values were omitted.  Call the postprocess vfunc on the
	return_rtx.
	(rtx_reader::rtx_reader): Add new "compact" param and pass to base
	class ctor.  Initialize m_in_call_function_usage.  Call
	one_time_initialization.
	* rtl-tests.c (selftest::test_uncond_jump): Call
	set_new_first_and_last_insn.
	* rtl.h (read_rtx): Wrap decl with #ifdef GENERATOR_FILE.
	* selftest-rtl.c: New file.
	* selftest-rtl.h (class selftest::rtl_dump_test): New class.
	(selftest::get_insn_by_uid): New decl.
	* selftest-run-tests.c (selftest::run_tests): Call
	read_rtl_function_c_tests.
	* selftest.h  (selftest::read_rtl_function_c_tests): New decl.
	* tree-dfa.c (ssa_default_def): Return NULL_TREE for rtl function
	dumps.

gcc/testsuite/ChangeLog:
	* selftests/asr_div1.rtl: New file.
	* selftests/aarch64: New subdirectory.
	* selftests/aarch64/times-two.rtl: New file.
	* selftests/bb-index.rtl: New file.
	* selftests/cfg-test.rtl: New file.
	* selftests/const-int.rtl: New file.
	* selftests/example-labels.rtl: New file.
	* selftests/insn-with-mode.rtl: New file.
	* selftests/jump-to-label-ref.rtl: New file.
	* selftests/jump-to-return.rtl: New file.
	* selftests/jump-to-simple-return.rtl: New file.
	* selftests/mem.rtl: New file.
	* selftests/note-insn-deleted.rtl: New file.
	* selftests/note_insn_basic_block.rtl: New file.
	* selftests/simple-cse.rtl: New file.
	* selftests/symbol-ref.rtl: New file.
	* selftests/x86_64: New subdirectory.
	* selftests/x86_64/call-insn.rtl: New file.
	* selftests/x86_64/copy-hard-reg-into-frame.rtl: New file.
	* selftests/x86_64/times-two.rtl: New file.
	* selftests/x86_64/unspec.rtl: New file.

From-SVN: r244110