PR tree-optimization/26854
	* tree-ssa-dse.c (dse_optimize_stmt): Avoid num_imm_uses when
	checking for zero or one use.
	* tree-ssa-dom.c (propagate_rhs_into_lhs): Similarly.
	* tree-cfgcleanup.c (merge_phi_nodes): Similarly.
	* tree-ssa-reassoc.c (negate_value): Similarly.
	(reassociate_bb): Similarly.

From-SVN: r113120