function.c (frame_required_for_rtx): Remove function.

function.c (frame_required_for_rtx): Remove function.

	* function.c (frame_required_for_rtx): Remove function.
	(requires_stack_frame_p): New arg set_up_by_prologue.  All callers
	changed.  Compute a set of mentioned registers and compare against
	the new arg rather than calling frame_required_for_rtx.
	(thread_prologue_and_epilogue_insns): Compute the set_up_by_prologue
	reg set.  Convert the unconverted_simple_returns mechanism to store
	jump insns rather than their basic blocks.  Also check the
	orig_entry_edge destination for new blocks.

From-SVN: r179654