tree-scalar-evolution.c (get_scalar_evolution): Handle default-defs and types we do not want to analyze.

2017-10-11  Richard Biener  <rguenther@suse.de>

	* tree-scalar-evolution.c (get_scalar_evolution): Handle
	default-defs and types we do not want to analyze.
	(interpret_loop_phi): Replace unreachable code with an assert.
	(compute_scalar_evolution_in_loop): Remove and inline ...
	(analyze_scalar_evolution_1): ... here, replacing condition with
	what makes the intent clearer.  Remove handling of cases
	get_scalar_evolution now handles.

From-SVN: r253629