tree-vect-generic.c (expand_vector_operations_1): Check optab exists before use it.

gcc/

	* tree-vect-generic.c (expand_vector_operations_1): Check
	optab exists before use it.

gcc/testsuite/

	* g++.dg/pr68062.C: New test.

From-SVN: r229275

gcc/ChangeLog

 2015-10-23  Ilya Enkovich  <enkovich.gnu@gmail.com>
 
+	* tree-vect-generic.c (expand_vector_operations_1): Check
+	optab exists before use it.
+
+2015-10-23  Ilya Enkovich  <enkovich.gnu@gmail.com>
+
 	* tree-vect-generic.c (expand_vector_condition): Avoid
 	uninitialized variable warning.
 

gcc/testsuite/ChangeLog

+2015-10-23  Ilya Enkovich  <enkovich.gnu@gmail.com>
+
+	* g++.dg/pr68062.C: New test.
+
 2015-10-23  Jeff Law  <law@redhat.com>
 
 	PR tree-optimization/67830

gcc/testsuite/g++.dg/pr68062.C

+/* { dg-do compile } */
+/* { dg-options "-funsigned-char" } */
+
+typedef char __attribute__ ((vector_size (4))) v4qi;
+typedef unsigned char __attribute__ ((vector_size (4))) uv4qi;
+
+v4qi v;
+void ret(char a)
+{
+  v4qi c={a,a,a,a};
+  uv4qi d={a,a,a,a};
+  v = (c!=d);
+}

gcc/tree-vect-generic.c

@@ -1533,7 +1533,8 @@ expand_vector_operations_1 (gimple_stmt_iterator *gsi)
       && TYPE_MODE (TREE_TYPE (type)) == TYPE_MODE (TREE_TYPE (srhs1)))
     {
       op = optab_for_tree_code (code, TREE_TYPE (type), optab_scalar);
-      if (optab_handler (op, TYPE_MODE (TREE_TYPE (type))) != CODE_FOR_nothing)
+      if (op != unknown_optab
+	  && optab_handler (op, TYPE_MODE (TREE_TYPE (type))) != CODE_FOR_nothing)
 	{
 	  tree slhs = make_ssa_name (TREE_TYPE (srhs1));
 	  gimple *repl = gimple_build_assign (slhs, code, srhs1, srhs2);