Come up with {,UN}LIKELY macros.

Come up with {,UN}LIKELY macros.

gcc/c/ChangeLog:

	* c-parser.cc (c_parser_conditional_expression): Use {,UN}LIKELY
	macros.
	(c_parser_binary_expression): Likewise.

gcc/cp/ChangeLog:

	* cp-gimplify.cc (cp_genericize_r): Use {,UN}LIKELY
	macros.
	* parser.cc (cp_finalize_omp_declare_simd): Likewise.
	(cp_finalize_oacc_routine): Likewise.

gcc/ChangeLog:

	* system.h (LIKELY): Define.
	(UNLIKELY): Likewise.
	* domwalk.cc (sort_bbs_postorder): Use {,UN}LIKELY
	macros.
	* dse.cc (set_position_unneeded): Likewise.
	(set_all_positions_unneeded): Likewise.
	(any_positions_needed_p): Likewise.
	(all_positions_needed_p): Likewise.
	* expmed.cc (flip_storage_order): Likewise.
	* genmatch.cc (dt_simplify::gen_1): Likewise.
	* ggc-common.cc (gt_pch_save): Likewise.
	* print-rtl.cc: Likewise.
	* rtl-iter.h (T>::array_type::~array_type): Likewise.
	(T>::next): Likewise.
	* rtl-ssa/internals.inl: Likewise.
	* rtl-ssa/member-fns.inl: Likewise.
	* rtlanal.cc (T>::add_subrtxes_to_queue): Likewise.
	(rtx_properties::try_to_add_dest): Likewise.
	* rtlanal.h (growing_rtx_properties::repeat): Likewise.
	(vec_rtx_properties_base::~vec_rtx_properties_base): Likewise.
	* simplify-rtx.cc (simplify_replace_fn_rtx): Likewise.
	* sort.cc (likely): Likewise.
	(mergesort): Likewise.
	* wide-int.h (wi::eq_p): Likewise.
	(wi::ltu_p): Likewise.
	(wi::cmpu): Likewise.
	(wi::bit_and): Likewise.
	(wi::bit_and_not): Likewise.
	(wi::bit_or): Likewise.
	(wi::bit_or_not): Likewise.
	(wi::bit_xor): Likewise.
	(wi::add): Likewise.
	(wi::sub): Likewise.