give Bad nodes a mode

[libfirm] / ir / ir / irgopt.c

diff --git a/ir/ir/irgopt.c b/ir/ir/irgopt.c
index 1888d28..a4c454b 100644 (file)
--- a/ir/ir/irgopt.c
+++ b/ir/ir/irgopt.c
@@ -100,19 +100,44 @@ void local_optimize_node(ir_node *n)
        current_ir_graph = rem;
 }
 
+/**
+ * Enqueue all users of a node to a wait queue.
+ * Handles mode_T nodes.
+ */
+static void enqueue_users(ir_node *n, pdeq *waitq)
+{
+       const ir_edge_t *edge;
+
+       foreach_out_edge(n, edge) {
+               ir_node *succ = get_edge_src_irn(edge);
+
+               if (get_irn_link(succ) != waitq) {
+                       pdeq_putr(waitq, succ);
+                       set_irn_link(succ, waitq);
+               }
+               if (get_irn_mode(succ) == mode_T) {
+               /* A mode_T node has Proj's. Because most optimizations
+                       run on the Proj's we have to enqueue them also. */
+                       enqueue_users(succ, waitq);
+               }
+       }
+}
+
 /**
  * Block-Walker: uses dominance depth to mark dead blocks.
  */
 static void kill_dead_blocks(ir_node *block, void *env)
 {
-       (void) env;
+       pdeq *waitq = (pdeq*) env;
 
        if (get_Block_dom_depth(block) < 0) {
                /*
                 * Note that the new dominance code correctly handles
                 * the End block, i.e. it is always reachable from Start
                 */
-               set_Block_dead(block);
+               ir_graph *irg = get_irn_irg(block);
+               enqueue_users(block, waitq);
+               exchange(block, new_r_Bad(irg, mode_BB));
        }
 }
 
@@ -122,45 +147,19 @@ void local_optimize_graph(ir_graph *irg)
        ir_graph *rem = current_ir_graph;
        current_ir_graph = irg;
 
-       if (get_irg_dom_state(irg) == dom_consistent)
-               irg_block_walk_graph(irg, NULL, kill_dead_blocks, NULL);
-
        do_local_optimize(get_irg_end(irg));
 
        current_ir_graph = rem;
 }
 
-/**
- * Enqueue all users of a node to a wait queue.
- * Handles mode_T nodes.
- */
-static void enqueue_users(ir_node *n, pdeq *waitq)
-{
-       const ir_edge_t *edge;
-
-       foreach_out_edge(n, edge) {
-               ir_node *succ = get_edge_src_irn(edge);
-
-               if (get_irn_link(succ) != waitq) {
-                       pdeq_putr(waitq, succ);
-                       set_irn_link(succ, waitq);
-               }
-               if (get_irn_mode(succ) == mode_T) {
-               /* A mode_T node has Proj's. Because most optimizations
-                       run on the Proj's we have to enqueue them also. */
-                       enqueue_users(succ, waitq);
-               }
-       }
-}
-
 /**
  * Data flow optimization walker.
- * Optimizes all nodes and enqueue it's users
+ * Optimizes all nodes and enqueue its users
  * if done.
  */
 static void opt_walker(ir_node *n, void *env)
 {
-       pdeq *waitq = env;
+       pdeq *waitq = (pdeq*)env;
        ir_node *optimized;
 
        optimized = optimize_in_place_2(n);
@@ -184,14 +183,16 @@ int optimize_graph_df(ir_graph *irg)
 
        state = edges_assure(irg);
 
-       if (get_opt_global_cse())
-               set_irg_pinned(irg, op_pin_state_floats);
-
        /* Clean the value_table in irg for the CSE. */
        new_identities(irg);
 
-       if (get_irg_dom_state(irg) == dom_consistent)
-               irg_block_walk_graph(irg, NULL, kill_dead_blocks, NULL);
+       if (get_opt_global_cse()) {
+               set_irg_pinned(irg, op_pin_state_floats);
+       }
+
+       /* The following enables unreachable code elimination (=Blocks may be
+        * Bad). */
+       set_irg_state(irg, IR_GRAPH_STATE_BAD_BLOCK);
 
        /* invalidate info */
        set_irg_outs_inconsistent(irg);
@@ -207,12 +208,17 @@ int optimize_graph_df(ir_graph *irg)
         * so if it's not empty, the graph has been changed */
        changed = !pdeq_empty(waitq);
 
-       /* finish the wait queue */
-       while (! pdeq_empty(waitq)) {
-               ir_node *n = pdeq_getl(waitq);
-               if (! is_Bad(n))
+       do {
+               /* finish the wait queue */
+               while (! pdeq_empty(waitq)) {
+                       ir_node *n = (ir_node*)pdeq_getl(waitq);
                        opt_walker(n, waitq);
-       }
+               }
+               /* kill newly generated unreachable code */
+               set_irg_outs_inconsistent(irg);
+               compute_doms(irg);
+               irg_block_walk_graph(irg, NULL, kill_dead_blocks, waitq);
+       } while (! pdeq_empty(waitq));
 
        del_pdeq(waitq);
 
@@ -223,9 +229,11 @@ int optimize_graph_df(ir_graph *irg)
 
        /* Finally kill BAD and doublets from the keep alives.
           Doing this AFTER edges where deactivated saves cycles */
-       end  = get_irg_end(irg);
+       end = get_irg_end(irg);
        remove_End_Bads_and_doublets(end);
 
+       clear_irg_state(irg, IR_GRAPH_STATE_BAD_BLOCK);
+
        current_ir_graph = rem;
        return changed;
 }