also do unreachable code elimination during gcse

diff --git a/ir/ir/irgopt.c b/ir/ir/irgopt.c
index fc27fb5..ee977ae 100644 (file)
--- a/ir/ir/irgopt.c
+++ b/ir/ir/irgopt.c
@@ -187,16 +187,16 @@ int optimize_graph_df(ir_graph *irg)
 
        if (get_opt_global_cse()) {
                set_irg_pinned(irg, op_pin_state_floats);
-       } else {
-               /* The following enables unreachable code elimination (=Blocks may be
-                * Bad). We cannot enable it in global_cse nodes since we can't
-                * determine a nodes block there and therefore can't remove all code
-                * in unreachable blocks */
-               set_irg_state(irg, IR_GRAPH_STATE_BAD_BLOCK);
-               if (get_irg_dom_state(irg) == dom_consistent)
-                       irg_block_walk_graph(irg, NULL, kill_dead_blocks, NULL);
        }
 
+       /* The following enables unreachable code elimination (=Blocks may be
+        * Bad). We cannot enable it in global_cse nodes since we can't
+        * determine a nodes block there and therefore can't remove all code
+        * in unreachable blocks */
+       set_irg_state(irg, IR_GRAPH_STATE_BAD_BLOCK);
+       if (get_irg_dom_state(irg) == dom_consistent)
+               irg_block_walk_graph(irg, NULL, kill_dead_blocks, NULL);
+
        /* invalidate info */
        set_irg_outs_inconsistent(irg);
        set_irg_doms_inconsistent(irg);

diff --git a/ir/ir/iropt.c b/ir/ir/iropt.c
index ac017a3..3565713 100644 (file)
--- a/ir/ir/iropt.c
+++ b/ir/ir/iropt.c
@@ -6274,10 +6274,8 @@ static ir_node *gigo(ir_node *node)
 {
        ir_op *op = get_irn_op(node);
 
-       /* Nodes in bad blocks are bad.
-        * Beware: we can only read the block of a non-floating node. */
-       if (op != op_Block && is_irn_pinned_in_irg(node)
-           && is_Bad(get_nodes_block(node))) {
+       /* Code in "Bad" blocks is unreachable and can be replaced by Bad */
+       if (op != op_Block && is_Bad(get_nodes_block(node))) {
            ir_graph *irg = get_irn_irg(node);
                return get_irg_bad(irg);
        }
@@ -6304,7 +6302,7 @@ static ir_node *gigo(ir_node *node)
        }
 
        return node;
-}  /* gigo */
+}
 
 /**
  * These optimizations deallocate nodes from the obstack.

diff --git a/ir/opt/code_placement.c b/ir/opt/code_placement.c
index c8eccef..581da79 100644 (file)
--- a/ir/opt/code_placement.c
+++ b/ir/opt/code_placement.c
@@ -45,14 +45,6 @@ static bool is_block_reachable(ir_node *block)
        return get_Block_dom_depth(block) >= 0;
 }
 
-/* mark node as not-visited */
-static void clear_irn_visited(ir_node *node)
-{
-       ir_graph    *irg     = get_irn_irg(node);
-       ir_visited_t visited = get_irg_visited(irg);
-       set_irn_visited(node, visited-1);
-}
-
 /**
  * Find the earliest correct block for node n.  --- Place n into the
  * same Block as its dominance-deepest Input.
@@ -112,20 +104,7 @@ static void place_floats_early(ir_node *n, waitq *worklist)
        arity = get_irn_arity(n);
        place_floats_early(block, worklist);
        for (i = 0; i < arity; ++i) {
-               ir_node *pred       = get_irn_n(n, i);
-               ir_node *pred_block = get_nodes_block(pred);
-
-               /* gcse can lead to predecessors of reachable code being unreachable.
-                * Move them into the current block in this case */
-               if (!is_block_reachable(pred_block)) {
-                       ir_node *new_pred_block = block;
-                       assert(get_irn_pinned(pred) == op_pin_state_floats);
-                       if (is_Phi(n)) {
-                               new_pred_block = get_Block_cfgpred_block(block, i);
-                       }
-                       set_nodes_block(pred, new_pred_block);
-                       clear_irn_visited(pred);
-               }
+               ir_node *pred = get_irn_n(n, i);
                place_floats_early(pred, worklist);
        }