re PR tree-optimization/55955 (ICE in optab_for_tree_code, at optabs.c:402)

	PR tree-optimization/55955
	* tree-vect-loop.c (vectorizable_reduction): Give up early on
	*SHIFT_EXPR and *ROTATE_EXPR codes.

	* gcc.c-torture/compile/pr55955.c: New test.

From-SVN: r195190

gcc/ChangeLog

 2013-01-15  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/55955
+	* tree-vect-loop.c (vectorizable_reduction): Give up early on
+	*SHIFT_EXPR and *ROTATE_EXPR codes.
+
 	PR tree-optimization/48766
 	* opts.c (common_handle_option): For -fwrapv disable -ftrapv, for
 	-ftrapv disable -fwrapv.

gcc/testsuite/ChangeLog

+2013-01-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/55955
+	* gcc.c-torture/compile/pr55955.c: New test.
+
 2013-01-15  Dodji Seketeli  <dodji@redhat.com>
 
 	PR c++/55663

gcc/testsuite/gcc.c-torture/compile/pr55955.c

+/* PR tree-optimization/55955 */
+
+int b;
+
+void
+foo (int x)
+{
+  int a;
+  for (a = x; a < 2; a++)
+    for (b = 0; b < 2; b++)
+      *(unsigned short *) 0x100000UL %= 46;
+}

gcc/tree-vect-loop.c

@@ -4776,6 +4776,17 @@ vectorizable_reduction (gimple stmt, gimple_stmt_iterator *gsi,
     {
       /* 4. Supportable by target?  */
 
+      if (code == LSHIFT_EXPR || code == RSHIFT_EXPR
+	  || code == LROTATE_EXPR || code == RROTATE_EXPR)
+	{
+	  /* Shifts and rotates are only supported by vectorizable_shifts,
+	     not vectorizable_reduction.  */
+          if (dump_enabled_p ())
+	    dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
+			     "unsupported shift or rotation.");
+	  return false;
+	}
+
       /* 4.1. check support for the operation in the loop  */
       optab = optab_for_tree_code (code, vectype_in, optab_default);
       if (!optab)