- BugFix: kill partitions with 0 blocks either

[libfirm] / ir / opt / scalar_replace.c

diff --git a/ir/opt/scalar_replace.c b/ir/opt/scalar_replace.c
index 8c87f77..9fcb8d5 100644 (file)
--- a/ir/opt/scalar_replace.c
+++ b/ir/opt/scalar_replace.c
@@ -23,9 +23,7 @@
  * @author  Beyhan Veliev, Michael Beck
  * @version $Id$
  */
-#ifdef HAVE_CONFIG_H
 #include "config.h"
-#endif
 
 #include <string.h>
 
@@ -270,36 +268,34 @@ int is_address_taken(ir_node *sel)
  *
  * @param ent  the entity that will be scalar replaced
  * @param sel  a Sel node that selects some fields of this entity
- *
- * Uses the visited flag to mark already linked Sel nodes.
  */
-static void link_all_leave_sels(ir_entity *ent, ir_node *sel) {
-       int i, flag = 1;
+static int link_all_leave_sels(ir_entity *ent, ir_node *sel) {
+       int i, is_leave = 1;
 
        for (i = get_irn_n_outs(sel) - 1; i >= 0; --i) {
                ir_node *succ = get_irn_out(sel, i);
 
                if (is_Sel(succ)) {
+                       /* the current leave has further Sel's, no leave */
+                       is_leave = 0;
                        link_all_leave_sels(ent, succ);
-                       flag = 0;
+               } else if (is_Id(succ)) {
+                       is_leave &= link_all_leave_sels(ent, succ);
                }
        }
 
-       if (flag) {
-               /* if Sel nodes with memory inputs are used, a entity can be
-                * visited more than once causing a ring here, so we use the
-                * node flag to mark linked nodes
-                */
-               if (irn_visited_else_mark(sel))
-                       return;
+       if (is_leave) {
+               /* beware of Id's */
+               sel = skip_Id(sel);
 
                /* we know we are at a leave, because this function is only
-                * called if the address is NOT taken, so succ must be a Load
-                * or a Store node
+                * called if the address is NOT taken, so sel's successor(s)
+                * must be Loads or Stores
                 */
                set_irn_link(sel, get_entity_link(ent));
                set_entity_link(ent, sel);
        }
+       return is_leave;
 }
 
 /* we need a special address that serves as an address taken marker */
@@ -326,9 +322,6 @@ static int find_possible_replacements(ir_graph *irg) {
        int     i;
        int     res = 0;
 
-       ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
-       inc_irg_visited(irg);
-
        /*
         * First, clear the link field of all interesting entities.
         */
@@ -370,7 +363,8 @@ static int find_possible_replacements(ir_graph *irg) {
                        /* we can handle arrays, structs and atomic types yet */
                        if (is_Array_type(ent_type) || is_Struct_type(ent_type) || is_atomic_type(ent_type)) {
                                if (is_address_taken(succ)) {
-                                       if (get_entity_link(ent)) /* killing one */
+                                        /* killing one */
+                                       if (get_entity_link(ent))
                                                --res;
                                        set_entity_link(ent, ADDRESS_TAKEN);
                                } else {
@@ -383,7 +377,6 @@ static int find_possible_replacements(ir_graph *irg) {
                }
        }
 
-       ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
        return res;
 }
 
@@ -581,13 +574,14 @@ static void topologic_walker(ir_node *node, void *ctx) {
 
                DB((dbg, SET_LEVEL_3, "replacing by value %u\n", vnum));
 
+               block = get_nodes_block(node);
+               set_cur_block(block);
+
                /* Beware: A Store can contain a hidden conversion in Firm. */
                val = get_Store_value(node);
                if (get_irn_mode(val) != env->modes[vnum])
                        val = new_d_Conv(get_irn_dbg_info(node), val, env->modes[vnum]);
 
-               block = get_nodes_block(node);
-               set_cur_block(block);
                set_value(vnum, val);
 
                mem = get_Store_mem(node);
@@ -651,6 +645,10 @@ int scalar_replacement_opt(ir_graph *irg) {
        /* Call algorithm that computes the out edges */
        assure_irg_outs(irg);
 
+       /* we use the link firld to store the VNUM */
+       ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
+       irp_reserve_resources(irp,  IR_RESOURCE_ENTITY_LINK);
+
        /* Find possible scalar replacements */
        if (find_possible_replacements(irg)) {
                DB((dbg, SET_LEVEL_1, "Scalar Replacement: %s\n", get_entity_name(get_irg_entity(irg))));
@@ -718,6 +716,9 @@ int scalar_replacement_opt(ir_graph *irg) {
                DEL_ARR_F(modes);
        }
 
+       ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
+       irp_free_resources(irp, IR_RESOURCE_ENTITY_LINK);
+
        current_ir_graph = rem;
        return res;
 }