This patch generalises various places that used hwi rtx accessors so
that they can handle poly_ints instead.  In many cases these changes
are by inspection rather than because something had shown them to be
necessary.

2018-06-12  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* poly-int.h (can_div_trunc_p): Add new overload in which all values
	are poly_ints.
	* alias.c (get_addr): Extend CONST_INT handling to poly_int_rtx_p.
	(memrefs_conflict_p): Likewise.
	(init_alias_analysis): Likewise.
	* cfgexpand.c (expand_debug_expr): Likewise.
	* combine.c (combine_simplify_rtx, force_int_to_mode): Likewise.
	* cse.c (fold_rtx): Likewise.
	* explow.c (adjust_stack, anti_adjust_stack): Likewise.
	* expr.c (emit_block_move_hints): Likewise.
	(clear_storage_hints, push_block, emit_push_insn): Likewise.
	(store_expr_with_bounds, reduce_to_bit_field_precision): Likewise.
	(emit_group_load_1): Use rtx_to_poly_int64 for group offsets.
	(emit_group_store): Likewise.
	(find_args_size_adjust): Use strip_offset.  Use rtx_to_poly_int64
	to read the PRE/POST_MODIFY increment.
	* calls.c (store_one_arg): Use strip_offset.
	* rtlanal.c (rtx_addr_can_trap_p_1): Extend CONST_INT handling to
	poly_int_rtx_p.
	(set_noop_p): Use rtx_to_poly_int64 for the elements selected
	by a VEC_SELECT.
	* simplify-rtx.c (avoid_constant_pool_reference): Use strip_offset.
	(simplify_binary_operation_1): Extend CONST_INT handling to
	poly_int_rtx_p.
	* var-tracking.c (compute_cfa_pointer): Take a poly_int64 rather
	than a HOST_WIDE_INT.
	(hard_frame_pointer_adjustment): Change from HOST_WIDE_INT to
	poly_int64.
	(adjust_mems, add_stores): Update accodingly.
	(vt_canonicalize_addr): Track polynomial offsets.
	(emit_note_insn_var_location): Likewise.
	(vt_add_function_parameter): Likewise.
	(vt_initialize): Likewise.

From-SVN: r261530