2010-01-06  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-pre.c (name_to_id): New global.
	(alloc_expression_id): Simplify SSA name handling.
	(lookup_expression_id): Likewise.
	(init_pre): Zero name_to_id.
	(fini_pre): Free it.

From-SVN: r155676