re PR tree-optimization/81297 (ICE in get_single_symbol)

2017-08-01  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/81297
	* tree-vrp.c (get_single_symbol): Remove assert, instead drop
	TREE_OVERFLOW from INTEGER_CSTs.

	* gcc.dg/torture/pr81297.c: New testcase.

From-SVN: r250758

gcc/ChangeLog

+2017-08-01  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/81297
+	* tree-vrp.c (get_single_symbol): Remove assert, instead drop
+	TREE_OVERFLOW from INTEGER_CSTs.
+
 2017-07-31  Segher Boessenkool  <segher@kernel.crashing.org>
 
 	* config/rs6000/rs6000.c (enum rs6000_reg_type): Delete trailing comma.

gcc/testsuite/ChangeLog

+2017-08-01  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/81297
+	* gcc.dg/torture/pr81297.c: New testcase.
+
 2017-07-31  Uros Bizjak  <ubizjak@gmail.com>
 
 	* gcc.target/i386/naked-1.c (dg-options): Add -fno-pic.

gcc/testsuite/gcc.dg/torture/pr81297.c

+/* { dg-do compile } */
+
+int
+nf (int gy, int x0)
+{
+  while (gy < 1)
+    ++x0;
+
+  gy += !!gy;
+  if (gy < 0)
+    {
+      x0 += gy;
+      return (x0 > (gy + x0)) ? (1 / 0) : 1; /* { dg-warning "division by zero" } */
+    }
+}
+

gcc/tree-vrp.c

@@ -796,7 +796,8 @@ get_single_symbol (tree t, bool *neg, tree *inv)
   if (TREE_CODE (t) != SSA_NAME)
     return NULL_TREE;
 
-  gcc_assert (! inv_ || ! TREE_OVERFLOW_P (inv_));
+  if (inv_ && TREE_OVERFLOW_P (inv_))
+    inv_ = drop_tree_overflow (inv_);
 
   *neg = neg_;
   *inv = inv_;