* bitmap.h (nBITMAP_WORD_BITS): Remove.
	(BITMAP_WORD_BITS): Force unsigned by use of 1u.
	(BITMAP_ELEMENT_WORDS, BITMAP_ELEMENT_ALL_BITS): Remove
	unnecessary casts.
	(bitmap_first_set_bit): Return unsigned, use ctzl.
	(bitmap_last_set_bit): Remove.
	* bitmap.c (bitmap_element_zerop, bitmap_copy): Make iterator
	unsigned.
	(bitmap_first_set_bit): Return unsigned, require non-empty bitmap,
	remove special case code for two word elements.
	(bitmap_last_set_bit): Remove.
	* ra-build.c (livethrough_conflicts_bb): Replace unnecessary use of
	bitmap_first_set_bit with bitmap_empty_p.
	* tree-outof-ssa.c (analyze_edges_for_bb): Likewise.
	* tree-ssa-pre.c (bitmap_print_value): Use simple flag rather than
	bitmap_last_bit_set.

From-SVN: r90478