Make SET_NEXT_INSN/SET_PREV_INSN require an rtx_insn

Make SET_NEXT_INSN/SET_PREV_INSN require an rtx_insn

gcc/
2014-08-28  David Malcolm  <dmalcolm@redhat.com>

	* rtl.h (SET_PREV_INSN): Strengthen param from rtx to rtx_insn *.
	(SET_NEXT_INSN): Likewise.
	(gen_rtvec_v): Add an overload for param types (int, rtx_insn **).

	* config/c6x/c6x.c (gen_one_bundle): Strengthen param "slot" from
	rtx * to rtx_insn **.  Introduce a new local rtx "seq", using it
	to split out the SEQUENCE from local "bundle", strengthening the
	latter from rtx to rtx_insn * to hold the insn holding the SEQUENCE.
	Strengthen locals "t" and "insn" from rtx to rtx_insn *.
	(c6x_gen_bundles): Strengthen locals "insn", "next", "last_call"
	and the type of the elements of the "slot" array from rtx to
	rtx_insn *.
	(reorg_split_calls): Likewise for locals "insn" and "next", and
	the type of the elements of the "slot" array.

	* config/frv/frv.c (frv_nops): Likewise for the elements of this
	array.
	(frv_function_prologue): Likewise for locals "insn", "next",
	"last_call".
	(frv_register_nop): Introduce a local "nop_insn" to be the
	rtx_insn * containing rtx "nop".

	* config/mep/mep.c (mep_make_bundle): Param "core" is sometimes
	used as an insn and sometimes as a pattern, so rename it to
	"core_insn_or_pat", and introduce local rtx_insn * "core_insn",
	using it where dealing with the core insn.

	* config/picochip/picochip.c (reorder_var_tracking_notes):
	Strengthen locals "insn", "next", "last_insn", "queue",
	"next_queue", "prev" from rtx to rtx_insn *.

	* emit-rtl.c (gen_rtvec_v): Add overloaded implementation for when
	the second param is an rtx_insn ** rather than an rtx **.
	(link_insn_into_chain): Strengthen locals "seq" and "sequence"
	from rtx to rtx_sequence *, and introduce local named "sequence",
	using methods of rtx_sequence to clarify the code.
	(remove_insn): Introduce local rtx_sequence * named "sequence" and
	use its methods.
	(emit_insn_after_1): Strengthen return type from rtx to rtx_insn *.
	Rename param "after" to "uncast_after", reintroducing "after" as a
	local rtx_insn * with a checked cast.
	(emit_pattern_after_noloc): Rename param "after" to "uncast_after",
	reintroducing "after" as a local rtx_insn * with a checked cast.
	Strengthen local "last" from rtx to rtx_insn * and remove the
	now-redundant checked casts.
	(copy_delay_slot_insn): Strengthen return type and param from rtx
	to rtx_insn *.

	* haifa-sched.c (reemit_notes): Strengthen params "insn" and
	"last" from rtx to rtx_insn *.

From-SVN: r214685