-BugFix: exp_gen sets must be cleaned

[r20382]

diff --git a/ir/opt/gvn_pre.c b/ir/opt/gvn_pre.c
index a9498d8..811b7f0 100644 (file)
--- a/ir/opt/gvn_pre.c
+++ b/ir/opt/gvn_pre.c
@@ -723,15 +723,15 @@ static void eliminate_nodes(elim_pair *pairs) {
  */
 void do_gvn_pre(ir_graph *irg)
 {
-       struct obstack obst;
-       pre_env a_env;
+       struct obstack       obst;
+       pre_env              a_env;
        optimization_state_t state;
-       block_info *bl_info;
-       unsigned antic_iter, insert_iter;
+       block_info           *bl_info;
+       unsigned             antic_iter, insert_iter;
+       ir_node              *value, *expr;
 
        /* register a debug mask */
        FIRM_DBG_REGISTER(dbg, "firm.opt.gvn_pre");
-       firm_dbg_set_mask(dbg, SET_LEVEL_2);
 
        /* edges will crash if enabled due to our allocate on other obstack trick */
        edges_deactivate(irg);
@@ -771,6 +771,16 @@ void do_gvn_pre(ir_graph *irg)
        /* allocate block info for all blocks */
        irg_walk_blkwise_graph(irg, NULL, topo_walker, &a_env);
 
+       /* clean the exp_gen set. Doing this here saves the cleanup in the iteration. */
+       for (bl_info = a_env.list; bl_info != NULL; bl_info = bl_info->next) {
+               ir_valueset_iterator_t iter;
+
+               foreach_valueset(bl_info->exp_gen, value, expr, iter) {
+                       if (!is_clean(expr))
+                               ir_valueset_remove_iterator(bl_info->exp_gen, &iter);
+               }
+       }
+
        /* compute the available value sets for all blocks */
        dom_tree_walk_irg(irg, compute_avail_top_down, NULL, &a_env);
 
@@ -783,7 +793,6 @@ void do_gvn_pre(ir_graph *irg)
        do {
                DB((dbg, LEVEL_1, "Antic_in Iteration %d starts ...\n", ++antic_iter));
                a_env.changes = 0;
-               //irg_block_walk_graph(irg, compute_antic, NULL, &a_env);
                postdom_tree_walk_irg(irg, compute_antic, NULL, &a_env);
                a_env.first_iter = 0;
                DB((dbg, LEVEL_1, "------------------------\n"));