PR tree-optimization/52563
	PR tree-optimization/62173
	* tree-ssa-loop-ivopts.c (struct iv): New field.  Reorder fields.
	(alloc_iv, set_iv): New parameter.
	(determine_biv_step): Delete.
	(find_bivs): Inline original determine_biv_step.  Pass new
	argument to set_iv.
	(idx_find_step): Use no_overflow information for conversion.
	* tree-scalar-evolution.c (analyze_scalar_evolution_in_loop): Let
	resolve_mixers handle folded_casts.
	(instantiate_scev_name): Change bool parameter to bool pointer.
	(instantiate_scev_poly, instantiate_scev_binary): Ditto.
	(instantiate_array_ref, instantiate_scev_not): Ditto.
	(instantiate_scev_3, instantiate_scev_2): Ditto.
	(instantiate_scev_1, instantiate_scev_r): Ditto.
	(instantiate_scev_convert, ): Change parameter.  Pass argument
	to chrec_convert_aggressive.
	(instantiate_scev): Change argument.
	(resolve_mixers): New parameter and set it.
	(scev_const_prop): New argument.
	* tree-scalar-evolution.h (resolve_mixers): New parameter.
	* tree-chrec.c (convert_affine_scev): Call chrec_convert instead
	of chrec_conert_1.
	(chrec_convert): New parameter.  Move definition below.
	(chrec_convert_aggressive): New parameter and set it.  Call
	convert_affine_scev.
	* tree-chrec.h (chrec_convert): New parameter.
	(chrec_convert_aggressive): Ditto.

	gcc/testsuite/ChangeLog
	PR tree-optimization/52563
	PR tree-optimization/62173
	* gcc.dg/tree-ssa/scev-3.c: Remove xfail.
	* gcc.dg/tree-ssa/scev-4.c: Ditto.

From-SVN: r224009