2008-08-20  Richard Guenther  <rguenther@suse.de>

	* tree-vrp.c (found_in_subgraph): Remove.
	(live): New global static.
	(live_on_edge): New function.
	(blocks_visited): Remove.
	(register_edge_assert_for_2): Use live_on_edge.
	(find_conditional_asserts): Remove code dealing with
	found_in_subgraph.  Do not walk the CFG.
	(find_switch_asserts): Likewise.
	(find_assert_locations_1): Renamed from find_assert_locations.
	Move finding assert locations for conditional and switch
	statements first.  Update live bitmap.  Do not walk the CFG.
	(find_assert_locations): New function.
	(insert_range_assertions): Remove entry of CFG walk.
	Adjust call to find_assert_locations.
	* tree-ssa-pre.c (do_regular_insertion): Ignore critical edges
	that only can appear because of fake exit edges but assert we
	never try to insert on those.
	(fini_pre): Do not remove fake exit edges here...
	(execute_pre): ...but here, before committing edge inserts.

	* gcc.dg/tree-ssa/pr20701.c: Scan vrp1 dump.
	* gcc.dg/tree-ssa/ssa-dom-thread-1.c: Pass -fno-tree-vrp.
	* gcc.dg/tree-ssa/ssa-pre-20.c: New testcase.

From-SVN: r139263