* semantics.c (constexpr_call): New datatype.
	(constexpr_call_table): New global table.
	(constexpr_call_hash): New.
	(constexpr_call_equal): Likewise.
	(maybe_initialize_constexpr_call_table): Likewise.
	(lookup_parameter_binding): Likewise.
	(cxx_eval_builtin_function_call): Likewise.
	(cxx_bind_parameters_in_call): Likewise.
	(cxx_eval_call_expression): Likewise.
	(cxx_eval_unary_expression): Likewise.
	(cxx_eval_binary_expression): Likewise.
	(cxx_eval_conditional_expression): Likewise.
	(cxx_eval_array_reference): Likewise.
	(cxx_eval_component_reference): Likewise.
	(cxx_eval_logical_expression): Likewise.
	(cxx_eval_object_construction): Likewise.
	(cxx_eval_constant_expression): Likewise.
	(cxx_eval_indirect_ref): Likewise.
	(cxx_constant_value): Likewise.
	(cxx_eval_bare_aggregate): Likewise.
	(adjust_temp_type): New.
	(reduced_constant_expression_p): New.
	(verify_constant): New.
	(cxx_eval_vec_init, cxx_eval_vec_init_1): New.
	(cxx_eval_outermost_constant_expr): New.
	(maybe_constant_value, maybe_constant_init): New.
	(cxx_eval_constant_expression): Use them.
	* cp-tree.h: Declare fns.

Co-Authored-By: Jason Merrill <jason@redhat.com>

From-SVN: r166166