Call compute_overall_effect_of_inner_loop from instantiate_scev_name.

2010-06-09  Sebastian Pop  <sebastian.pop@amd.com>

	* tree-scalar-evolution.c (instantiate_scev_name): Do not fail
	the scev analysis when the variable is not used outside the loop
	in a close phi node: call compute_overall_effect_of_inner_loop.

From-SVN: r160510

gcc/ChangeLog

 2010-06-09  Sebastian Pop  <sebastian.pop@amd.com>
 
+	* tree-scalar-evolution.c (instantiate_scev_name): Do not fail
+	the scev analysis when the variable is not used outside the loop
+	in a close phi node: call compute_overall_effect_of_inner_loop.
+
+2010-06-09  Sebastian Pop  <sebastian.pop@amd.com>
+
 	* graphite-sese-to-poly.c (single_pred_cond): Renamed
 	single_pred_cond_non_loop_exit.  Return NULL for loop exit edges.
 	(build_sese_conditions_before): Renamed call to single_pred_cond.

gcc/tree-scalar-evolution.c

@@ -2172,9 +2172,19 @@ instantiate_scev_name (basic_block instantiate_below,
       else
 	res = chrec;
 
-      if (res == NULL_TREE
-	  || !dominated_by_p (CDI_DOMINATORS, instantiate_below,
-			      gimple_bb (SSA_NAME_DEF_STMT (res))))
+      /* When there is no loop_closed_phi_def, it means that the
+	 variable is not used after the loop: try to still compute the
+	 value of the variable when exiting the loop.  */
+      if (res == NULL_TREE)
+	{
+	  loop_p loop = loop_containing_stmt (SSA_NAME_DEF_STMT (chrec));
+	  res = analyze_scalar_evolution (loop, chrec);
+	  res = compute_overall_effect_of_inner_loop (loop, res);
+	  res = instantiate_scev_r (instantiate_below, evolution_loop, res,
+				    fold_conversions, cache, size_expr);
+	}
+      else if (!dominated_by_p (CDI_DOMINATORS, instantiate_below,
+				gimple_bb (SSA_NAME_DEF_STMT (res))))
 	res = chrec_dont_know;
     }