re PR tree-optimization/71823 (g++ segfaults with -mfma and -ftree-slp-vectorize)

	PR tree-optimization/71823
	* tree-vect-stmts.c (vectorizable_operation): Use vect_get_vec_defs
	to get vec_oprnds2 from op2.

	* gcc.dg/vect/pr71823.c: New test.

From-SVN: r238229

gcc/ChangeLog

+2016-07-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/71823
+	* tree-vect-stmts.c (vectorizable_operation): Use vect_get_vec_defs
+	to get vec_oprnds2 from op2.
+
 2016-07-11  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/predicates.md (x86_64_immediate_operand) <case CONST>:

gcc/testsuite/ChangeLog

+2016-07-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/71823
+	* gcc.dg/vect/pr71823.c: New test.
+
 2016-07-11  David Malcolm  <dmalcolm@redhat.com>
 
 	* gcc.dg/plugin/location_overflow_plugin.c (plugin_init): Avoid

gcc/testsuite/gcc.dg/vect/pr71823.c

+/* PR tree-optimization/71823 */
+/* { dg-do compile } */
+/* { dg-additional-options "-mfma" { target i?86-*-* x86_64-*-* } } */
+
+float a[4], b[4];
+
+int
+main ()
+{
+  int i;
+  for (i = 0; i < 4; ++i)
+    b[i] = __builtin_fma (1024.0f, 1024.0f, a[i]);
+  return 0;
+}

gcc/tree-vect-stmts.c

@@ -5362,11 +5362,8 @@ vectorizable_operation (gimple *stmt, gimple_stmt_iterator *gsi,
 	    vect_get_vec_defs (op0, NULL_TREE, stmt, &vec_oprnds0, NULL,
 			       slp_node, -1);
 	  if (op_type == ternary_op)
-	    {
-	      vec_oprnds2.create (1);
-	      vec_oprnds2.quick_push (vect_get_vec_def_for_operand (op2,
-		                                                    stmt));
-	    }
+	    vect_get_vec_defs (op2, NULL_TREE, stmt, &vec_oprnds2, NULL,
+			       slp_node, -1);
 	}
       else
 	{