* basic-block.h (XMALLOC_REG_SET, XFREE_REG_SET): New.
	(struct basic_block_def): Remove local_set and cond_local_set
	fields.  Update comment for global_live_at_start.
	* flow.c (calculate_global_regs_live): Allocate local_sets and
	cond_local_sets here as arrays of bitmaps previously stored in
	bb->local_set and bb->cond_local_set.  Use xmalloc instead of
	obstack allocated bitmaps.

From-SVN: r90390