Minor changes

[libfirm] / ir / be / belistsched.c

diff --git a/ir/be/belistsched.c b/ir/be/belistsched.c
index 3174ba2..1671248 100644 (file)
--- a/ir/be/belistsched.c
+++ b/ir/be/belistsched.c
@@ -144,14 +144,23 @@ static INLINE usage_stats_t *get_usage_stats(ir_node *irn)
        return us;
 }
 
-static int max_hops_walker(ir_node *irn, ir_node *tgt, int depth, unsigned visited_nr)
+static int max_hops_walker(reg_pressure_selector_env_t *env, ir_node *irn, ir_node *curr_bl, int depth, unsigned visited_nr)
 {
-       int i, n;
-       int res = 0;
-
-       if(irn != tgt) {
-               res = INT_MAX;
+       ir_node *bl = get_nodes_block(irn);
+       /*
+        * If the reached node is not in the block desired,
+        * return the value passed for this situation.
+        */
+       if(get_nodes_block(irn) != bl)
+               return block_dominates(bl, curr_bl) ? 0 : INT_MAX;
 
+       /*
+        * If the node is in the current block but not
+        * yet scheduled, we keep on searching from that node.
+        */
+       if(!pset_find_ptr(env->already_scheduled, irn)) {
+               int i, n;
+               int res = 0;
                for(i = 0, n = get_irn_arity(irn); i < n; ++i) {
                        ir_node *operand = get_irn_n(irn, i);
 
@@ -159,34 +168,38 @@ static int max_hops_walker(ir_node *irn, ir_node *tgt, int depth, unsigned visit
                                int tmp;
 
                                set_irn_visited(operand, visited_nr);
-                               tmp = max_hops_walker(operand, tgt, depth + 1, visited_nr);
+                               tmp = max_hops_walker(env, operand, bl, depth + 1, visited_nr);
                                res = MAX(tmp, res);
                        }
                }
+
+               return res;
        }
 
-       return res;
+       /*
+        * If the node is in the current block and scheduled, return
+        * the depth which indicates the number of steps to the
+        * region of scheduled nodes.
+        */
+       return depth;
 }
 
 static int compute_max_hops(reg_pressure_selector_env_t *env, ir_node *irn)
 {
        ir_node *bl   = get_nodes_block(irn);
        ir_graph *irg = get_irn_irg(bl);
-       int res       = INT_MAX;
+       int res       = 0;
 
        const ir_edge_t *edge;
 
        foreach_out_edge(irn, edge) {
-               ir_node *user = get_edge_src_irn(edge);
+               ir_node *user       = get_edge_src_irn(edge);
+               unsigned visited_nr = get_irg_visited(irg) + 1;
+               int max_hops;
 
-               if(get_nodes_block(user) == bl && !pset_find_ptr(env->already_scheduled, user)) {
-                       unsigned visited_nr = get_irg_visited(irg) + 1;
-                       int max_hops;
-
-                       set_irg_visited(irg, visited_nr);
-                       max_hops = max_hops_walker(user, irn, 0, visited_nr);
-                       res = MAX(res, max_hops);
-               }
+               set_irg_visited(irg, visited_nr);
+               max_hops = max_hops_walker(env, user, irn, 0, visited_nr);
+               res      = MAX(res, max_hops);
        }
 
        return res;
@@ -244,6 +257,23 @@ static void reg_pressure_block_free(void *block_env)
        free(env);
 }
 
+static int get_result_hops_sum(reg_pressure_selector_env_t *env, ir_node *irn)
+{
+       int res = 0;
+       if(get_irn_mode(irn) == mode_T) {
+               const ir_edge_t *edge;
+
+               foreach_out_edge(irn, edge)
+                       res += get_result_hops_sum(env, get_edge_src_irn(edge));
+       }
+
+       else if(mode_is_data(get_irn_mode(irn)))
+               res = compute_max_hops(env, irn);
+
+
+       return res;
+}
+
 static INLINE int reg_pr_costs(reg_pressure_selector_env_t *env, ir_node *irn)
 {
        int i, n;
@@ -256,10 +286,12 @@ static INLINE int reg_pr_costs(reg_pressure_selector_env_t *env, ir_node *irn)
                        sum += compute_max_hops(env, op);
        }
 
+       sum += get_result_hops_sum(env, irn);
+
        return sum;
 }
 
-ir_node *reg_pressure_select(void *block_env, pset *ready_set)
+static ir_node *reg_pressure_select(void *block_env, pset *ready_set)
 {
        reg_pressure_selector_env_t *env = block_env;
        ir_node *irn, *res     = NULL;
@@ -478,6 +510,15 @@ static void add_tuple_projs(block_sched_env_t *env, ir_node *irn)
 
 static ir_node *select_node(block_sched_env_t *be)
 {
+       ir_node *irn;
+
+       for(irn = pset_first(be->ready_set); irn; irn = pset_next(be->ready_set)) {
+               if(be_is_Keep(irn)) {
+                       pset_break(be->ready_set);
+                       return irn;
+               }
+       }
+
        return be->selector->select(be->selector_block_env, be->ready_set);
 }