Fixes PR 18403 and meta PR 21861.

	Fixes PR 18403 and meta PR 21861.
	* Makefile.in (tree-chrec.o): Depend on CFGLOOP_H and TREE_FLOW_H.
	* tree-chrec.c: Include cfgloop.h and tree-flow.h.
	(evolution_function_is_invariant_rec_p,
	evolution_function_is_invariant_p): New.
	(chrec_convert): Use an extra parameter AT_STMT for refining the
	information that is passed down to convert_step.  Integrate the
	code that was in count_ev_in_wider_type.
	* tree-chrec.h (count_ev_in_wider_type): Removed.
	(chrec_convert): Modify its declaration.
	(evolution_function_is_invariant_p): Declared.
	(evolution_function_is_affine_p): Use evolution_function_is_invariant_p.
	* tree-flow.h (can_count_iv_in_wider_type): Renamed convert_step.
	(scev_probably_wraps_p): Declared.
	* tree-scalar-evolution.c (count_ev_in_wider_type): Removed.
	(follow_ssa_edge_in_rhs, interpret_rhs_modify_expr):
	Use an extra parameter AT_STMT for refining the information that is
	passed down to convert_step.
	(follow_ssa_edge_inner_loop_phi, follow_ssa_edge,
	analyze_scalar_evolution_1): Initialize AT_STMT with the current
	analyzed statement.
	(instantiate_parameters_1): Don't know yet how to initialize AT_STMT.
	* tree-ssa-loop-ivopts.c (idx_find_step): Update the use of
	can_count_iv_in_wider_type to use convert_step.
	* tree-ssa-loop-niter.c (can_count_iv_in_wider_type_bound): Move
	code that is independent of the loop over the known iteration
	bounds to convert_step_widening, the rest is moved to
	proved_non_wrapping_p.
	(scev_probably_wraps_p): New.
	(can_count_iv_in_wider_type): Renamed convert_step.
	* tree-vrp.c (adjust_range_with_scev): Take an extra AT_STMT parameter.
	Use scev_probably_wraps_p for computing init_is_max.
	(vrp_visit_assignment): Pass the current analyzed statement to
	adjust_range_with_scev.
	(execute_vrp): Call estimate_numbers_of_iterations for refining the
	information provided by scev analyzer.

testsuite:

	* testsuite/gcc.dg/vect/vect-77.c: Remove xfail from lp64.
	* testsuite/gcc.dg/vect/vect-78.c: Same.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@100718 138bc75d-0d04-0410-961f-82ee72b054a4