[Patch] Drop constant overflow flag in adjust_range_with_scev when possible

[Patch] Drop constant overflow flag in adjust_range_with_scev when possible

2015-11-23  Richard Biener  <rguenth@gcc.gnu.com>
            Jiong Wang  <jiong.wang@arm.com>

gcc/
  PR tree-optimization/68317
  PR tree-optimization/68326
  * tree-vrp.c (adjust_range_with_scev): Call drop_tree_overflow if the
  final min and max are not infinity.

gcc/testsuite/
  * gcc.dg/pr68317.c: New testcase.

From-SVN: r230754