add recursion on the inner loops

We now check that all data references in the current loop and inner loops
contained within loop are valid in an outer region before declaring that the
outer loop is a valid scop.

2015-09-30  Sebastian Pop  <s.pop@samsung.com>
	    Aditya Kumar  <aditya.k7@samsung.com>

	PR tree-optimization/67754
	* graphite-scop-detection.c (loop_body_is_valid_scop): Add missing
	recursion on the inner loops.

Co-Authored-By: Aditya Kumar <aditya.k7@samsung.com>

From-SVN: r228346

gcc/ChangeLog

+2015-10-01  Sebastian Pop  <s.pop@samsung.com>
+	    Aditya Kumar  <aditya.k7@samsung.com>
+
+	PR tree-optimization/67754
+	* graphite-scop-detection.c (loop_body_is_valid_scop): Add missing
+	recursion on the inner loops.
+
 2015-10-01  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>
 
 	* cfganal.c, compare-elim.c, coverage.c, cprop.c, df-scan.c,

gcc/graphite-scop-detection.c

@@ -805,6 +805,18 @@ loop_body_is_valid_scop (loop_p loop, sese_l scop)
 	return false;
     }
   free (bbs);
+
+  if (loop->inner)
+    {
+      loop = loop->inner;
+      while (loop)
+	{
+	  if (!loop_body_is_valid_scop (loop, scop))
+	    return false;
+	  loop = loop->next;
+	}
+    }
+
   return true;
 }