* df.h (df_insn_delete): Adjust prototype.
	* emit-rtl.c (remove_insn): Pass a basic block to df_insn_delete
	and let it decide whether mark the basic block dirty.
	(set_insn_deleted): Only pass INSN_P insns to df_insn_delete.
	* df-scan.c (df_insn_info_delete): New helper function, split
	off from df_insn_delete.
	(df_scan_free_bb_info): Use it.
	(df_insn_rescan, df_insn_rescan_all, df_process_deferred_rescans):
	Likewise.
	(df_insn_delete): Likewise.  Take insn rtx as argument.  Verify
	that the insn is actually an insn and it has a non-NULL basic block.
	Do not mark basic block dirty if only deleting a DEBUG_INSN.

From-SVN: r196977