* basic-block.h (struct edge_list): Stucture to maintain a vector
	of edges.
	(EDGE_INDEX_NO_EDGE, EDGE_INDEX, INDEX_EDGE_PRED_BB, INDEX_EDGE_SUCC_BB,
	 INDEX_EDGE, NUM_EDGES): New Macros for accessing edge list.
	(create_edge_list, free_edge-List, print_edge_list, verify_edge_list):
	New function prototypes.
	* flow.c (create_edge_list): Function to create an edge list.
	(free_edge_list): Discards memory used by an edge list.
	(print_edge_list): Debug output showing an edge list.
	(verify_edge_list): Internal consistency check for an edge list.

From-SVN: r28732