poly_int: push_block/emit_push_insn

poly_int: push_block/emit_push_insn

This patch changes the "extra" parameters to push_block and
emit_push_insn from int to poly_int64.

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

gcc/
	* expr.h (push_block, emit_push_insn): Change the "extra" parameter
	from HOST_WIDE_INT to poly_int64.
	* expr.c (push_block, emit_push_insn): Likewise.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r255918