tree-vrp.c (vrp_visit_assignment_or_call): Changed to Return VR.

tree-vrp.c (vrp_visit_assignment_or_call): Changed to Return VR.

gcc/ChangeLog:

2016-08-20  Kugan Vivekanandarajah  <kuganv@linaro.org>

	* tree-vrp.c (vrp_visit_assignment_or_call): Changed to Return VR.
	(vrp_visit_cond_stmt): Just sets TAKEN_EDGE_P.
	(vrp_visit_switch_stmt): Likewise.
	(extract_range_from_stmt): Factored out from vrp_visit_stmt.
	(extract_range_from_phi_node): Factored out from vrp_visit_phi_stmt.
	(vrp_visit_stmt): Use extract_range_from_stmt.
	(vrp_visit_phi_node): Use extract_range_from_phi_node.

From-SVN: r239639