Make IPA predicate::size a poly_int64

Make IPA predicate::size a poly_int64

This patch changes the IPA predicate::size field from a HOST_WIDE_INT
to a poly_int64.

2019-08-07  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* data-streamer.h (streamer_write_poly_uint64): Declare.
	(streamer_read_poly_uint64): Likewise.
	* data-streamer-in.c (streamer_read_poly_uint64): New function.
	* data-streamer-out.c (streamer_write_poly_uint64): Likewise.
	* ipa-predicate.h (condition::size): Turn into a poly_int64.
	(add_condition): Take a poly_int64 size.
	* ipa-predicate.c (add_condition): Likewise.
	* ipa-prop.h (ipa_load_from_parm_agg): Take a poly_int64 size pointer.
	* ipa-prop.c (ipa_load_from_parm_agg): Likewise.
	(ipcp_modif_dom_walker::before_dom_children): Update accordingly.
	* ipa-fnsummary.c (evaluate_conditions_for_known_args): Handle
	condition::size as a poly_int64.
	(unmodified_parm_1): Take a poly_int64 size pointer.
	(unmodified_parm): Likewise.
	(unmodified_parm_or_parm_agg_item): Likewise.
	(set_cond_stmt_execution_predicate): Update accordingly.
	(set_switch_stmt_execution_predicate): Likewise.
	(will_be_nonconstant_expr_predicate): Likewise.
	(will_be_nonconstant_predicate): Likewise.
	(inline_read_section): Stream condition::size as a poly_int.
	(ipa_fn_summary_write): Likewise.

From-SVN: r274162