Fix usage of POW2 histogram

	* value-prof.c (gimple_divmod_values_to_profile): Do not
	instrument MOD histogram if a value is not a SSA name.
	* gcc.dg/tree-prof/val-prof-9.c: New test.

From-SVN: r239305

gcc/ChangeLog

 2016-08-09  Martin Liska  <mliska@suse.cz>
 
+	* value-prof.c (gimple_divmod_values_to_profile): Do not
+	instrument MOD histogram if a value is not a SSA name.
+
+2016-08-09  Martin Liska  <mliska@suse.cz>
+
 	* value-prof.c (dump_histogram_value): Swap pow2 and non-pow2
 	values.
 

gcc/testsuite/ChangeLog

 2016-08-09  Martin Liska  <mliska@suse.cz>
 
+	* gcc.dg/tree-prof/val-prof-9.c: New test.
+
+2016-08-09  Martin Liska  <mliska@suse.cz>
+
 	* gcc.dg/tree-prof/val-prof-8.c: New test.
 
 2016-08-09  Martin Jambor  <mjambor@suse.cz>

gcc/testsuite/gcc.dg/tree-prof/val-prof-9.c

+/* { dg-options "-O0 -fdump-tree-optimized" } */
+
+int
+main (int argc, char **argv)
+{
+  unsigned u = (argc - 1);
+  int counter = 0;
+
+  for (unsigned i = 0; i < 100; i++)
+  {
+    counter += u % 16;
+  }
+
+  return counter;
+}
+
+/* autofdo does not do value profiling so far */
+/* { dg-final-use-not-autofdo { scan-tree-dump-times "__gcov_pow2_profiler" 0 "optimized" } } */

gcc/value-prof.c

@@ -1950,7 +1950,8 @@ gimple_divmod_values_to_profile (gimple *stmt, histogram_values *values)
       /* For mod, check whether it is not often a noop (or replaceable by
 	 a few subtractions).  */
       if (gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR
-	  && TYPE_UNSIGNED (type))
+	  && TYPE_UNSIGNED (type)
+	  && TREE_CODE (divisor) == SSA_NAME)
 	{
           tree val;
           /* Check for a special case where the divisor is power of 2.  */