X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Firdom.c;h=dfe3336f27690cb8de76d8a9feab0f5907a91f9d;hb=58e533a640ff427362877a3d2f1a5142c96391e1;hp=ffb2c97b91c8bab517920251c73d233b62f84811;hpb=4ae48f6511003a6d6c99b1766de00c39bdfb6c12;p=libfirm

diff --git a/ir/ana/irdom.c b/ir/ana/irdom.c
index ffb2c97b9..dfe3336f2 100644
--- a/ir/ana/irdom.c
+++ b/ir/ana/irdom.c
@@ -1,12 +1,12 @@
 /*
  * Project:     libFIRM
  * File name:   ir/ana/irdom.c
- * Purpose:     Construct and access dominator tree.
+ * Purpose:     Construct and access dominator / post dominator tree.
  * Author:      Goetz Lindenmaier
- * Modified by:
+ * Modified by: Michael Beck, Rubino Geiss
  * Created:     2.2002
  * CVS-ID:      $Id$
- * Copyright:   (c) 2002-2003 Universität Karlsruhe
+ * Copyright:   (c) 2002-2003 Universitaet Karlsruhe
  * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
  */
 
@@ -27,11 +27,12 @@
 #include "irnode_t.h"
 #include "ircons_t.h"
 
-#define get_dom_info(bl) (&(bl)->attr.block.dom)
 
+#define get_dom_info(bl)  (&(bl)->attr.block.dom)
+#define get_pdom_info(bl) (&(bl)->attr.block.pdom)
 
 /*--------------------------------------------------------------------*/
-/** Accessing the dominator data structures                          **/
+/** Accessing the dominator and post dominator data structures       **/
 /*--------------------------------------------------------------------*/
 
 ir_node *get_Block_idom(const ir_node *bl) {
@@ -63,24 +64,74 @@ void set_Block_idom(ir_node *bl, ir_node *n) {
 	}
 }
 
-int get_Block_pre_num(const ir_node *bl) {
+ir_node *get_Block_ipostdom(const ir_node *bl) {
+  assert(is_Block(bl));
+  if (get_Block_postdom_depth(bl) == -1) {
+    /* This block is not reachable from Start */
+    return new_Bad();
+  }
+  return get_pdom_info(bl)->idom;
+}
+
+void set_Block_ipostdom(ir_node *bl, ir_node *n) {
+	dom_info *bli = get_pdom_info(bl);
+
   assert(get_irn_op(bl) == op_Block);
-  return bl->attr.block.dom.pre_num;
+
+	/* Set the immediate post dominator of bl to n */
+	bli->idom = n;
+
+	/*
+	 * If we don't set the root of the post dominator tree
+	 * Append bl to the post dominates queue of n.
+	 */
+	if(n != NULL) {
+		dom_info *ni = get_pdom_info(n);
+
+		bli->next = ni->first;
+		ni->first = bl;
+	}
 }
 
-void set_Block_pre_num(ir_node *bl, int num) {
+int get_Block_dom_pre_num(const ir_node *bl) {
   assert(get_irn_op(bl) == op_Block);
-  bl->attr.block.dom.pre_num = num;
+  return get_dom_info(bl)->pre_num;
+}
+
+void set_Block_dom_pre_num(ir_node *bl, int num) {
+  assert(get_irn_op(bl) == op_Block);
+  get_dom_info(bl)->pre_num = num;
 }
 
 int get_Block_dom_depth(const ir_node *bl) {
   assert(get_irn_op(bl) == op_Block);
-  return bl->attr.block.dom.dom_depth;
+  return get_dom_info(bl)->dom_depth;
 }
 
 void set_Block_dom_depth(ir_node *bl, int depth) {
   assert(get_irn_op(bl) == op_Block);
-  bl->attr.block.dom.dom_depth = depth;
+  get_dom_info(bl)->dom_depth = depth;
+}
+
+
+int get_Block_postdom_pre_num(const ir_node *bl) {
+  assert(get_irn_op(bl) == op_Block);
+  return get_pdom_info(bl)->pre_num;
+}
+
+void set_Block_postdom_pre_num(ir_node *bl, int num) {
+  assert(get_irn_op(bl) == op_Block);
+  get_pdom_info(bl)->pre_num = num;
+}
+
+int get_Block_postdom_depth(const ir_node *bl) {
+  assert(get_irn_op(bl) == op_Block);
+  return get_pdom_info(bl)->dom_depth;
+}
+
+void set_Block_postdom_depth(ir_node *bl, int depth) {
+  assert(get_irn_op(bl) == op_Block);
+  get_pdom_info(bl)->dom_depth = depth;
 }
 
 unsigned get_Block_dom_tree_pre_num(const ir_node *bl)
@@ -95,29 +146,79 @@ unsigned get_Block_dom_max_subtree_pre_num(const ir_node *bl)
 	return get_dom_info(bl)->max_subtree_pre_num;
 }
 
+unsigned get_Block_pdom_tree_pre_num(const ir_node *bl)
+{
+	assert(is_Block(bl));
+	return get_pdom_info(bl)->tree_pre_num;
+}
+
+unsigned get_Block_pdom_max_subtree_pre_num(const ir_node *bl)
+{
+	assert(is_Block(bl));
+	return get_pdom_info(bl)->max_subtree_pre_num;
+}
+
+/* Check, if a block dominates another block. */
 int block_dominates(const ir_node *a, const ir_node *b)
 {
 	const dom_info *ai, *bi;
 
-	assert(is_Block(a) && is_Block(b));
-	ai = get_dom_info(a);
-	bi = get_dom_info(b);
-	return bi->tree_pre_num - ai->tree_pre_num
-		<= ai->max_subtree_pre_num - ai->tree_pre_num;
+	if (is_Block(a) && is_Block(b)) {
+		ai = get_dom_info(a);
+		bi = get_dom_info(b);
+		return bi->tree_pre_num - ai->tree_pre_num
+			<= ai->max_subtree_pre_num - ai->tree_pre_num;
+	}
+
+	return 0;
 }
 
+/* Get the first node in the list of nodes dominated by a given block. */
 ir_node *get_Block_dominated_first(const ir_node *bl)
 {
 	assert(is_Block(bl));
 	return get_dom_info(bl)->first;
 }
 
+/* Get the next node in a list of nodes which are dominated by some
+ * other node. */
 ir_node *get_Block_dominated_next(const ir_node *bl)
 {
 	assert(is_Block(bl));
 	return get_dom_info(bl)->next;
 }
 
+/* Check, if a block post dominates another block. */
+int block_postdominates(const ir_node *a, const ir_node *b)
+{
+	const dom_info *ai, *bi;
+
+	if (is_Block(a) && is_Block(b)) {
+		ai = get_pdom_info(a);
+		bi = get_pdom_info(b);
+		return bi->tree_pre_num - ai->tree_pre_num
+			<= ai->max_subtree_pre_num - ai->tree_pre_num;
+	}
+
+	return 0;
+}
+
+/* Get the first node in the list of nodes post dominated by a given block. */
+ir_node *get_Block_postdominated_first(const ir_node *bl)
+{
+	assert(is_Block(bl));
+	return get_pdom_info(bl)->first;
+}
+
+/* Get the next node in a list of nodes which are post dominated by some
+ * other node. */
+ir_node *get_Block_postdominated_next(const ir_node *bl)
+{
+	assert(is_Block(bl));
+	return get_pdom_info(bl)->next;
+}
+
+/* Visit all nodes in the dominator subtree of a given node. */
 void dom_tree_walk(ir_node *bl, irg_walk_func *pre,
 		irg_walk_func *post, void *env)
 {
@@ -134,10 +235,28 @@ void dom_tree_walk(ir_node *bl, irg_walk_func *pre,
 		post(bl, env);
 }
 
+/* Visit all nodes in the post dominator subtree of a given node. */
+void postdom_tree_walk(ir_node *bl, irg_walk_func *pre,
+		irg_walk_func *post, void *env)
+{
+	ir_node *p;
+
+	if(pre)
+		pre(bl, env);
+
+	postdominates_for_each(bl, p) {
+		postdom_tree_walk(p, pre, post, env);
+	}
+
+	if(post)
+		post(bl, env);
+}
+
+/* Walk over the dominator tree of an irg starting at the root. */
 void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
 		irg_walk_func *post, void *env)
 {
-	/* The root of the dominator tree should be the start node. */
+	/* The root of the dominator tree should be the Start block. */
 	ir_node *root = get_irg_start_block(irg);
 
   assert(irg->dom_state == dom_consistent
@@ -148,7 +267,23 @@ void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
 	dom_tree_walk(root, pre, post, env);
 }
 
-static void assign_tree_pre_order(ir_node *bl, void *data)
+/* Walk over the post dominator tree of an irg starting at the root. */
+void postdom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
+		irg_walk_func *post, void *env)
+{
+	/* The root of the dominator tree should be the End block. */
+	ir_node *root = get_irg_end_block(irg);
+
+  assert(irg->pdom_state == dom_consistent
+			&& "The dominators of the irg must be consistent");
+	assert(root && "The end block of the graph is NULL?");
+	assert(get_pdom_info(root)->idom == NULL
+			&& "The End block node in the graph must be the root of the post dominator tree");
+	postdom_tree_walk(root, pre, post, env);
+}
+
+
+static void assign_tree_dom_pre_order(ir_node *bl, void *data)
 {
 	unsigned *num = data;
 	dom_info *bi = get_dom_info(bl);
@@ -156,7 +291,7 @@ static void assign_tree_pre_order(ir_node *bl, void *data)
 	bi->tree_pre_num = (*num)++;
 }
 
-static void assign_tree_pre_order_max(ir_node *bl, void *data)
+static void assign_tree_dom_pre_order_max(ir_node *bl, void *data)
 {
 	dom_info *bi = get_dom_info(bl);
 	ir_node *p;
@@ -173,58 +308,100 @@ static void assign_tree_pre_order_max(ir_node *bl, void *data)
 	assert(bi->max_subtree_pre_num >= bi->tree_pre_num);
 }
 
+static void assign_tree_postdom_pre_order(ir_node *bl, void *data)
+{
+	unsigned *num = data;
+	dom_info *bi = get_pdom_info(bl);
+
+	bi->tree_pre_num = (*num)++;
+}
+
+static void assign_tree_postdom_pre_order_max(ir_node *bl, void *data)
+{
+	dom_info *bi = get_pdom_info(bl);
+	ir_node *p;
+	unsigned max = 0;
+	unsigned children = 0;
+
+	for(p = bi->first; p; p = get_pdom_info(p)->next) {
+		unsigned max_p = get_pdom_info(p)->max_subtree_pre_num;
+		max = max > max_p ? max : max_p;
+		children++;
+	}
+
+	bi->max_subtree_pre_num = children > 0 ? max : bi->tree_pre_num;
+	assert(bi->max_subtree_pre_num >= bi->tree_pre_num);
+}
+
 /*--------------------------------------------------------------------*/
-/*  Building and Removing the dominator datastructure                 */
+/*  Building and Removing the dominator data structure                */
 /*--------------------------------------------------------------------*/
 
-static void count_and_init_blocks(ir_node *bl, void *env) {
+/**
+ * count the number of blocks and clears the dominance info
+ */
+static void count_and_init_blocks_dom(ir_node *bl, void *env) {
   int *n_blocks = (int *) env;
   (*n_blocks) ++;
 
 	memset(get_dom_info(bl), 0, sizeof(dom_info));
   set_Block_idom(bl, NULL);
-  set_Block_pre_num(bl, -1);
+  set_Block_dom_pre_num(bl, -1);
   set_Block_dom_depth(bl, -1);
 }
 
-/* temporary type used while constructing the dominator tree. */
+/**
+ * count the number of blocks and clears the post dominance info
+ */
+static void count_and_init_blocks_pdom(ir_node *bl, void *env) {
+  int *n_blocks = (int *) env;
+  (*n_blocks) ++;
+
+	memset(get_pdom_info(bl), 0, sizeof(dom_info));
+  set_Block_ipostdom(bl, NULL);
+  set_Block_postdom_pre_num(bl, -1);
+  set_Block_postdom_depth(bl, -1);
+}
+
+/** temporary type used while constructing the dominator / post dominator tree. */
 typedef struct tmp_dom_info {
-  ir_node *block;               /* backlink */
+  ir_node *block;               /**< backlink */
 
-  struct tmp_dom_info *semi;	/* semidominator */
+  struct tmp_dom_info *semi;    /**< semidominator */
   struct tmp_dom_info *parent;
-  struct tmp_dom_info *label;	/* used for LINK and EVAL */
-  struct tmp_dom_info *ancestor;/* used for LINK and EVAL */
-  struct tmp_dom_info *dom;	/* After step 3, if the semidominator of w is
-				   its immediate dominator, then w->dom is the
-				   immediate dominator of w.  Otherwise w->dom
-				   is a vertex v whose number is smaller than
-				   w and whose immediate dominator is also w's
-				   immediate dominator. After step 4, w->dom
-				   is the immediate dominator of w.  */
-  struct tmp_dom_info *bucket;	/* set of vertices with same semidominator */
+  struct tmp_dom_info *label;   /**< used for LINK and EVAL */
+  struct tmp_dom_info *ancestor;/**< used for LINK and EVAL */
+  struct tmp_dom_info *dom;     /**< After step 3, if the semidominator of w is
+                                     its immediate dominator, then w->dom is the
+                                     immediate dominator of w.  Otherwise w->dom
+                                     is a vertex v whose number is smaller than
+                                     w and whose immediate dominator is also w's
+                                     immediate dominator. After step 4, w->dom
+                                     is the immediate dominator of w.  */
+  struct tmp_dom_info *bucket;  /**< set of vertices with same semidominator */
 } tmp_dom_info;
 
-/* Struct to pass info through walker. */
+/** Struct to pass info through walker. */
 typedef struct {
   tmp_dom_info *d;
   int used;
-
 } dom_env;
 
 
-/* Walks Blocks along the out datastructure.  If recursion started with
-   Start block misses control dead blocks. */
+/**
+ * Walks Blocks along the out data structure.  If recursion started with
+ * Start block misses control dead blocks.
+ */
 static void init_tmp_dom_info(ir_node *bl, tmp_dom_info *parent,
 			      tmp_dom_info *tdi_list, int* used) {
   tmp_dom_info *tdi;
   int i;
 
-  assert(get_irn_op(bl) == op_Block);
+  assert(is_Block(bl));
   if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl))
     return;
   mark_Block_block_visited(bl);
-  set_Block_pre_num(bl, *used);
+  set_Block_dom_pre_num(bl, *used);
 
   tdi = &tdi_list[*used];
   ++(*used);
@@ -237,15 +414,49 @@ static void init_tmp_dom_info(ir_node *bl, tmp_dom_info *parent,
   tdi->block = bl;
 
   /* Iterate */
-  for(i = 0; i < get_Block_n_cfg_outs(bl); i++) {
+  for (i = get_Block_n_cfg_outs(bl) - 1; i >= 0; --i) {
     ir_node *pred = get_Block_cfg_out(bl, i);
-    assert(get_irn_opcode(pred) == iro_Block);
+    assert(is_Block(pred));
     init_tmp_dom_info(pred, tdi, tdi_list, used);
   }
 }
 
-static void
-dom_compress (tmp_dom_info *v)
+/**
+ * Walks Blocks along the control flow.  If recursion started with
+ * End block misses blocks in endless loops.
+ */
+static void init_tmp_pdom_info(ir_node *bl, tmp_dom_info *parent,
+			      tmp_dom_info *tdi_list, int* used) {
+  tmp_dom_info *tdi;
+  int i;
+
+  assert(is_Block(bl));
+  if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl))
+    return;
+  mark_Block_block_visited(bl);
+  set_Block_postdom_pre_num(bl, *used);
+
+  tdi = &tdi_list[*used];
+  ++(*used);
+
+  tdi->semi = tdi;
+  tdi->label = tdi;
+  tdi->ancestor = NULL;
+  tdi->bucket = NULL;
+  tdi->parent = parent;
+  tdi->block = bl;
+
+  /* Iterate */
+  for (i = get_Block_n_cfgpreds(bl) - 1; i >= 0; --i) {
+    ir_node *pred = get_Block_cfgpred_block(bl, i);
+    if (is_Bad(pred))
+      continue;
+    assert(is_Block(pred));
+    init_tmp_pdom_info(pred, tdi, tdi_list, used);
+  }
+}
+
+static void dom_compress(tmp_dom_info *v)
 {
   assert (v->ancestor);
   if (v->ancestor->ancestor) {
@@ -257,19 +468,19 @@ dom_compress (tmp_dom_info *v)
   }
 }
 
-/* if V is a root, return v, else return the vertex u, not being the
-   root, with minimum u->semi on the path from v to its root. */
-INLINE static tmp_dom_info*
-dom_eval (tmp_dom_info *v)
+/**
+ * if V is a root, return v, else return the vertex u, not being the
+ * root, with minimum u->semi on the path from v to its root.
+ */
+INLINE static tmp_dom_info *dom_eval (tmp_dom_info *v)
 {
   if (!v->ancestor) return v;
   dom_compress (v);
   return v->label;
 }
 
-/* make V W's ancestor */
-INLINE static void
-dom_link (tmp_dom_info *v, tmp_dom_info *w)
+/** make V W's ancestor */
+INLINE static void dom_link(tmp_dom_info *v, tmp_dom_info *w)
 {
   w->ancestor = v;
 }
@@ -290,14 +501,14 @@ void compute_doms(ir_graph *irg) {
 
   /* Count the number of blocks in the graph. */
   n_blocks = 0;
-  irg_block_walk(get_irg_end(current_ir_graph), count_and_init_blocks, NULL, &n_blocks);
+  irg_block_walk(get_irg_end(current_ir_graph), count_and_init_blocks_dom, NULL, &n_blocks);
 
   /* Memory for temporary information. */
   tdi_list = xcalloc(n_blocks, sizeof(tdi_list[0]));
 
-  /* We need the out datastructure. */
+  /* We need the out data structure. */
   if (current_ir_graph->outs_state != outs_consistent)
-    compute_outs(current_ir_graph);
+    compute_irg_outs(current_ir_graph);
 
   /* this with a standard walker as passing the parent to the sons isn't
      simple. */
@@ -317,20 +528,18 @@ void compute_doms(ir_graph *irg) {
 
     /* Step 2 */
     irn_arity = get_irn_arity(w->block);
-    for (j = 0;  j < irn_arity;  j++) {
-      ir_node *cf_op = get_Block_cfgpred(w->block, j);
-      ir_node *pred  = get_nodes_block(cf_op);
+    for (j = 0; j < irn_arity;  j++) {
+      ir_node *pred = get_Block_cfgpred_block(w->block, j);
       tmp_dom_info *u;
 
-      if ((is_Bad(cf_op)) || (is_Bad(pred)) ||
-	  (get_Block_pre_num (pred) == -1))
-	continue;	/* control-dead */
+      if (is_Bad(pred) || (get_Block_dom_pre_num (pred) == -1))
+        continue;	/* control-dead */
 
-      u = dom_eval (&tdi_list[get_Block_pre_num(pred)]);
+      u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred)]);
       if (u->semi < w->semi) w->semi = u->semi;
     }
     /* Add w to w->semi's bucket.  w is in exactly one bucket, so
-       buckets can ben implemented as linked lists. */
+       buckets can been implemented as linked lists. */
     w->bucket = w->semi->bucket;
     w->semi->bucket = w;
 
@@ -346,16 +555,16 @@ void compute_doms(ir_graph *irg) {
 
       u = dom_eval (v);
       if (u->semi < v->semi)
-	v->dom = u;
+        v->dom = u;
       else
-	v->dom = w->parent;
+        v->dom = w->parent;
     }
   }
   /* Step 4 */
   tdi_list[0].dom = NULL;
   set_Block_idom(tdi_list[0].block, NULL);
   set_Block_dom_depth(tdi_list[0].block, 1);
-  for (i = 1;  i < n_blocks;  i++) {
+  for (i = 1; i < n_blocks;  i++) {
     tmp_dom_info *w = &tdi_list[i];
 
     if (w->dom != w->semi) w->dom = w->dom->dom;
@@ -364,18 +573,18 @@ void compute_doms(ir_graph *irg) {
   }
 
   /* clean up */
-  /*  free(tdi_list); @@@ does not work !!?? */
+  free(tdi_list);
   current_ir_graph = rem;
 
-	/* Do a walk over the tree and assign the tree pre orders. */
-	{
-		unsigned tree_pre_order = 0;
-		dom_tree_walk_irg(irg, assign_tree_pre_order,
-				assign_tree_pre_order_max, &tree_pre_order);
-	}
+  /* Do a walk over the tree and assign the tree pre orders. */
+  {
+    unsigned tree_pre_order = 0;
+    dom_tree_walk_irg(irg, assign_tree_dom_pre_order,
+      assign_tree_dom_pre_order_max, &tree_pre_order);
+  }
 }
 
-void free_dom_and_peace(ir_graph *irg) {
+void free_dom(ir_graph *irg) {
   /* Update graph state */
   assert(get_irg_phase_state(current_ir_graph) != phase_building);
   current_ir_graph->dom_state = dom_none;
@@ -383,3 +592,111 @@ void free_dom_and_peace(ir_graph *irg) {
   /* With the implementation right now there is nothing to free,
      but better call it anyways... */
 }
+
+/* Computes the post dominator trees.  Sets a flag in irg to "dom_consistent".
+   If the control flow of the graph is changed this flag must be set to
+   "dom_inconsistent".  */
+void compute_postdoms(ir_graph *irg) {
+  ir_graph *rem = current_ir_graph;
+  int n_blocks, used, i, j;
+  tmp_dom_info *tdi_list;
+
+  current_ir_graph = irg;
+
+  /* Update graph state */
+  assert(get_irg_phase_state(current_ir_graph) != phase_building);
+  current_ir_graph->pdom_state = dom_consistent;
+
+  /* Count the number of blocks in the graph. */
+  n_blocks = 0;
+  irg_block_walk(get_irg_end(current_ir_graph), count_and_init_blocks_pdom, NULL, &n_blocks);
+
+  /* Memory for temporary information. */
+  tdi_list = xcalloc(n_blocks, sizeof(tdi_list[0]));
+
+  /* We need the out data structure. */
+  if (current_ir_graph->outs_state != outs_consistent)
+    compute_irg_outs(current_ir_graph);
+
+  /* this with a standard walker as passing the parent to the sons isn't
+     simple. */
+  used = 0;
+  inc_irg_block_visited(current_ir_graph);
+  init_tmp_pdom_info(get_irg_end_block(current_ir_graph), NULL, tdi_list, &used);
+  /* If not all blocks are reachable from End by cfg edges this assertion
+     fails.
+     assert(used == n_blocks && "Precondition for dom construction violated"); */
+  n_blocks = used;
+
+
+  for (i = n_blocks-1; i > 0; i--) {  /* Don't iterate the root, it's done. */
+    int irn_arity;
+    tmp_dom_info *w = &tdi_list[i];
+    tmp_dom_info *v;
+
+    /* Step 2 */
+    irn_arity = get_Block_n_cfg_outs(w->block);
+    for (j = 0;  j < irn_arity;  j++) {
+      ir_node *succ = get_Block_cfg_out(w->block, j);
+      tmp_dom_info *u;
+
+      if (get_Block_postdom_pre_num (succ) == -1)
+        continue;	/* endless-loop */
+
+      u = dom_eval (&tdi_list[get_Block_postdom_pre_num(succ)]);
+      if (u->semi < w->semi) w->semi = u->semi;
+    }
+    /* Add w to w->semi's bucket.  w is in exactly one bucket, so
+       buckets can be implemented as linked lists. */
+    w->bucket = w->semi->bucket;
+    w->semi->bucket = w;
+
+    dom_link (w->parent, w);
+
+    /* Step 3 */
+    while (w->parent->bucket) {
+      tmp_dom_info *u;
+      v = w->parent->bucket;
+      /* remove v from w->parent->bucket */
+      w->parent->bucket = v->bucket;
+      v->bucket = NULL;
+
+      u = dom_eval(v);
+      if (u->semi < v->semi)
+        v->dom = u;
+      else
+        v->dom = w->parent;
+    }
+  }
+  /* Step 4 */
+  tdi_list[0].dom = NULL;
+  set_Block_ipostdom(tdi_list[0].block, NULL);
+  set_Block_postdom_depth(tdi_list[0].block, 1);
+  for (i = 1;  i < n_blocks;  i++) {
+    tmp_dom_info *w = &tdi_list[i];
+
+    if (w->dom != w->semi) w->dom = w->dom->dom;
+    set_Block_ipostdom(w->block, w->dom->block);
+    set_Block_postdom_depth(w->block, get_Block_postdom_depth(w->dom->block) + 1);
+  }
+
+  /* clean up */
+  free(tdi_list);
+  current_ir_graph = rem;
+
+  /* Do a walk over the tree and assign the tree pre orders. */
+  {
+    unsigned tree_pre_order = 0;
+    postdom_tree_walk_irg(irg, assign_tree_postdom_pre_order,
+      assign_tree_postdom_pre_order_max, &tree_pre_order);
+  }
+}
+
+void free_postdom(ir_graph *irg) {
+  /* Update graph state */
+  assert(get_irg_phase_state(current_ir_graph) != phase_building);
+  current_ir_graph->pdom_state = dom_none;
+
+  /* With the implementation right now there is nothing to free,
+     but better call it anyways... */
+}