This patch makes a few small poly_int64 changes to reload.c,
such as in the "decomposition" structure.  In practice, any
port with polynomial-sized modes should be using LRA rather
than reload, but it's easier to convert reload anyway than
to sprinkle to_constants everywhere.

2017-12-21  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* reload.h (reload::inc): Change from an int to a poly_int64_pod.
	* reload.c (combine_reloads, debug_reload_to_stream): Likewise.
	(decomposition): Change start and end from HOST_WIDE_INT
	to poly_int64_pod.
	(decompose, immune_p): Update accordingly.
	(find_inc_amount): Return a poly_int64 rather than an int.
	* reload1.c (inc_for_reload): Take the inc_amount as a poly_int64
	rather than an int.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r255915