New modref/ipa_modref optimization passes

New modref/ipa_modref optimization passes

2020-09-19  David Cepelik  <d@dcepelik.cz>
	    Jan Hubicka  <hubicka@ucw.cz>

	* Makefile.in: Add ipa-modref.c and ipa-modref-tree.c.
	* alias.c: (reference_alias_ptr_type_1): Export.
	* alias.h (reference_alias_ptr_type_1): Declare.
	* common.opt (fipa-modref): New.
	* gengtype.c (open_base_files): Add ipa-modref-tree.h and ipa-modref.h
	* ipa-modref-tree.c: New file.
	* ipa-modref-tree.h: New file.
	* ipa-modref.c: New file.
	* ipa-modref.h: New file.
	* lto-section-in.c (lto_section_name): Add ipa_modref.
	* lto-streamer.h (enum lto_section_type): Add LTO_section_ipa_modref.
	* opts.c (default_options_table): Enable ipa-modref at -O1+.
	* params.opt (-param=modref-max-bases, -param=modref-max-refs,
	-param=modref-max-tests): New params.
	* passes.def: Schedule pass_modref and pass_ipa_modref.
	* timevar.def (TV_IPA_MODREF): New timevar.
	(TV_TREE_MODREF): New timevar.
	* tree-pass.h (make_pass_modref): Declare.
	(make_pass_ipa_modref): Declare.
	* tree-ssa-alias.c (dump_alias_stats): Include ipa-modref-tree.h
	and ipa-modref.h
	(alias_stats): Add modref_use_may_alias, modref_use_no_alias,
	modref_clobber_may_alias, modref_clobber_no_alias, modref_tests.
	(dump_alias_stats): Dump new stats.
	(nonoverlapping_array_refs_p): Fix formating.
	(modref_may_conflict): New function.
	(ref_maybe_used_by_call_p_1): Use it.
	(call_may_clobber_ref_p_1): Use it.
	(call_may_clobber_ref_p): Update.
	(stmt_may_clobber_ref_p_1): Update.
	* tree-ssa-alias.h (call_may_clobber_ref_p_1): Update.