X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Firouts.c;h=d2c4576a77b940f1e0c3cde543574660cef77079;hb=c0bef4f5aded93790e8d181ec3fcdcd6429a3cd3;hp=1c7df898953f39d3ada1467e2780142942fb814b;hpb=dfc7b16a5025411227b421fee75e76ea35fa3157;p=libfirm

diff --git a/ir/ana/irouts.c b/ir/ana/irouts.c
index 1c7df8989..d2c4576a7 100644
--- a/ir/ana/irouts.c
+++ b/ir/ana/irouts.c
@@ -1,24 +1,29 @@
 /*
- * Project:     libFIRM
- * File name:   ir/ana/irouts.c
- * Purpose:     Compute and access out edges.
- * Author:      Goetz Lindenmaier
- * Modified by:
- * Created:     1.2002
- * CVS-ID:      $Id$
- * Copyright:   (c) 2002-2003 Universität Karlsruhe
- * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
+ * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
  */
 
- /**
-  * @file irouts.c Compute out edges for ir nodes (also called def-use edges).
-  *
-  * Copyright (C) 2002 by Universitaet Karlsruhe
-  * All rights reserved.
-  *
-  * Authors:  Goetz Lindenmaier
-  */
-
+/**
+ * @file
+ * @brief    Compute and access out edges (also called def-use edges).
+ * @author   Goetz Lindenmaier, Michael Beck
+ * @date     1.2002
+ * @version  $Id$
+ */
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
@@ -33,6 +38,9 @@
 #include "irgraph_t.h"
 #include "irprog_t.h"
 #include "irgwalk.h"
+#include "irtools.h"
+#include "irprintf.h"
+#include "error.h"
 
 #ifdef DEBUG_libfirm
 /* Note:  ir_node.out_valid and ir_graph.n_outs are only present when DEBUG_libfirm is defined */
@@ -44,154 +52,231 @@
 /** Accessing the out datastructures                                 **/
 /*--------------------------------------------------------------------*/
 
+#ifdef DEBUG_libfirm
 /** Clear the outs of a node */
-static void reset_outs (ir_node *node, void *unused)
+static void reset_outs(ir_node *node, void *unused) {
+	(void) unused;
+	node->out       = NULL;
+	node->out_valid = 0;
+}
+#endif
+
+int get_irn_outs_computed(const ir_node *node)
 {
-  node->out = NULL;
+	return node->out != NULL;
+}
+
+/* returns the number of successors of the node: */
+int get_irn_n_outs(ir_node *node) {
+	assert(node && node->kind == k_ir_node);
 #ifdef DEBUG_libfirm
-  node->out_valid = 0;
+	/* assert(node->out_valid); */
 #endif /* defined DEBUG_libfirm */
+	/* we misuse the first for the size info of the out array */
+	return node->out[0].pos;
 }
 
-/* returns the number of successors of the node: */
-int get_irn_n_outs    (ir_node *node) {
-  assert(node && node->kind == k_ir_node);
+/* Access successor n */
+ir_node *get_irn_out(ir_node *def, int pos) {
+	assert(pos >= 0 && pos < get_irn_n_outs(def));
 #ifdef DEBUG_libfirm
-  /* assert (node->out_valid); */
+	/* assert(def->out_valid); */
 #endif /* defined DEBUG_libfirm */
-  return (int)(node->out[0]);
+	return def->out[pos+1].use;
 }
 
 /* Access successor n */
-ir_node *get_irn_out      (ir_node *node, int pos) {
-  assert(pos >= 0 && pos < get_irn_n_outs(node));
+ir_node *get_irn_out_ex(ir_node *def, int pos, int *in_pos) {
+	assert(pos >= 0 && pos < get_irn_n_outs(def));
 #ifdef DEBUG_libfirm
-  /* assert (node->out_valid); */
+	/* assert(def->out_valid); */
 #endif /* defined DEBUG_libfirm */
-  return node->out[pos+1];
+	*in_pos = def->out[pos+1].pos;
+	return def->out[pos+1].use;
 }
 
-void set_irn_out      (ir_node *node, int pos, ir_node *out) {
-  assert(node && out);
-  assert(pos >= 0 && pos < get_irn_n_outs(node));
+void set_irn_out(ir_node *def, int pos, ir_node *use, int in_pos) {
+	assert(def && use);
+	assert(pos >= 0 && pos < get_irn_n_outs(def));
 #ifdef DEBUG_libfirm
-  node->out_valid = 1;          /* assume that this function is used correctly */
+	def->out_valid = 1;          /* assume that this function is used correctly */
 #endif /* defined DEBUG_libfirm */
-  node->out[pos+1] = out;
+	def->out[pos+1].use = use;
+	def->out[pos+1].pos = in_pos;
 }
 
+/* Return the number of control flow successors, ignore keep-alives. */
+int get_Block_n_cfg_outs(ir_node *bl) {
+	int i, n_cfg_outs = 0;
+	assert(bl && is_Block(bl));
+#ifdef DEBUG_libfirm
+	assert(bl->out_valid);
+#endif /* defined DEBUG_libfirm */
+	for (i = 1; i <= bl->out[0].pos; ++i) {
+		ir_node *succ = bl->out[i].use;
+		if (get_irn_mode(succ) == mode_X && !is_End(succ))
+			n_cfg_outs += succ->out[0].pos;
+	}
+	return n_cfg_outs;
+}
 
-int get_Block_n_cfg_outs (ir_node *bl) {
-  int i, n_cfg_outs = 0;
-  assert(bl && (get_irn_op(bl) == op_Block));
+/* Return the number of control flow successors, honor keep-alives. */
+int get_Block_n_cfg_outs_ka(ir_node *bl) {
+	int i, n_cfg_outs = 0;
+	assert(bl && is_Block(bl));
 #ifdef DEBUG_libfirm
-  assert (bl->out_valid);
+	assert(bl->out_valid);
 #endif /* defined DEBUG_libfirm */
-  for (i = 0; i < (int)bl->out[0]; i++)
-    if ((get_irn_mode(bl->out[i+1]) == mode_X) &&
-        (get_irn_op(bl->out[i+1]) != op_End))
-      n_cfg_outs++;
-  return n_cfg_outs;
+	for (i = 1; i <= bl->out[0].pos; ++i) {
+		ir_node *succ = bl->out[i].use;
+		if (get_irn_mode(succ) == mode_X) {
+
+			if (is_End(succ)) {
+				/* ignore End if we are in the Endblock */
+				if (get_nodes_block(succ) == bl)
+					continue;
+				else /* count Keep-alive as one */
+					n_cfg_outs += 1;
+			} else
+				n_cfg_outs += succ->out[0].pos;
+		}
+	}
+	return n_cfg_outs;
 }
 
+/* Access predecessor n, ignore keep-alives. */
+ir_node *get_Block_cfg_out(ir_node *bl, int pos) {
+	int i;
+	assert(bl && is_Block(bl));
+#ifdef DEBUG_libfirm
+	assert(bl->out_valid);
+#endif /* defined DEBUG_libfirm */
+	for (i = 1; i <= bl->out[0].pos; ++i) {
+		ir_node *succ = bl->out[i].use;
+		if (get_irn_mode(succ) == mode_X && !is_End(succ)) {
+			int n_outs = succ->out[0].pos;
+			if (pos < n_outs)
+				return succ->out[pos + 1].use;
+			else
+				pos -= n_outs;
+		}
+	}
+	return NULL;
+}
 
-ir_node *get_Block_cfg_out  (ir_node *bl, int pos) {
-  int i, out_pos = 0;
-  assert(bl && (get_irn_op(bl) == op_Block));
+/* Access predecessor n, honor keep-alives. */
+ir_node *get_Block_cfg_out_ka(ir_node *bl, int pos) {
+	int i, n_outs;
+	assert(bl && is_Block(bl));
 #ifdef DEBUG_libfirm
-  assert (bl->out_valid);
+	assert (bl->out_valid);
 #endif /* defined DEBUG_libfirm */
-  for (i = 0; i < (int)bl->out[0]; i++)
-    if ((get_irn_mode(bl->out[i+1]) == mode_X)  &&
-        (get_irn_op(bl->out[i+1]) != op_End)) {
-      if (out_pos == pos) {
-        ir_node *cfop = bl->out[i+1];
-        return cfop->out[0+1];
-      } else {
-        out_pos++;
-      }
-    }
-  return NULL;
-}
-
-static void irg_out_walk_2(ir_node *node,  irg_walk_func *pre,
-            irg_walk_func *post, void *env) {
-  int i;
-  ir_node *succ;
+	for (i = 1; i <= bl->out[0].pos; ++i) {
+		ir_node *succ = bl->out[i].use;
+		if (get_irn_mode(succ) == mode_X) {
+			if (is_End(succ)) {
+				ir_node *end_bl = get_nodes_block(succ);
+				if (end_bl == bl) {
+					/* ignore End if we are in the Endblock */
+					continue;
+				}
+				if (pos == 0) {
+					/* handle keep-alive here: return the Endblock instead of the End node */
+					return end_bl;
+				} else
+					--pos;
+			} else {
+				n_outs = succ->out[0].pos;
+				if (pos < n_outs)
+					return succ->out[pos + 1].use;
+				else
+					pos -= n_outs;
+			}
+		}
+	}
+	return NULL;
+}
 
-  assert(node);
-  assert(get_irn_visited(node) < get_irg_visited(current_ir_graph));
+static void irg_out_walk_2(ir_node *node, irg_walk_func *pre,
+            irg_walk_func *post, void *env) {
+	int     i, n;
+	ir_node *succ;
 
-  set_irn_visited(node, get_irg_visited(current_ir_graph));
+	assert(node);
+	assert(get_irn_visited(node) < get_irg_visited(current_ir_graph));
 
-  if (pre) pre(node, env);
+	set_irn_visited(node, get_irg_visited(current_ir_graph));
 
-  for (i = 0; i < get_irn_n_outs(node); i++) {
-    succ = get_irn_out(node, i);
-    if (get_irn_visited(succ) < get_irg_visited(current_ir_graph))
-      irg_out_walk_2(succ, pre, post, env);
-  }
+	if (pre) pre(node, env);
 
-  if (post) post(node, env);
+	for (i = 0, n = get_irn_n_outs(node); i < n; ++i) {
+		succ = get_irn_out(node, i);
+		if (get_irn_visited(succ) < get_irg_visited(current_ir_graph))
+			irg_out_walk_2(succ, pre, post, env);
+	}
 
-  return;
+	if (post) post(node, env);
 }
 
 void irg_out_walk(ir_node *node,
-            irg_walk_func *pre, irg_walk_func *post,
-            void *env) {
-  assert(node);
-  if (get_irg_outs_state(current_ir_graph) != outs_none) {
-    inc_irg_visited (current_ir_graph);
-    irg_out_walk_2(node, pre, post, env);
-  }
-  return;
+                  irg_walk_func *pre, irg_walk_func *post,
+                  void *env) {
+	assert(node);
+	if (get_irg_outs_state(current_ir_graph) != outs_none) {
+		inc_irg_visited (current_ir_graph);
+		irg_out_walk_2(node, pre, post, env);
+	}
 }
 
 static void irg_out_block_walk2(ir_node *bl,
-            irg_walk_func *pre, irg_walk_func *post,
-            void *env) {
-  int i;
-
-  if(get_Block_block_visited(bl) < get_irg_block_visited(current_ir_graph)) {
-    set_Block_block_visited(bl, get_irg_block_visited(current_ir_graph));
-
-    if(pre)
-      pre(bl, env);
-
-    for(i = 0; i < get_Block_n_cfg_outs(bl); i++) {
-      /* find the corresponding predecessor block. */
-      ir_node *pred = get_Block_cfg_out(bl, i);
-      /* recursion */
-      irg_out_block_walk2(pred, pre, post, env);
-    }
-
-    if(post)
-      post(bl, env);
-  }
-  return;
+                                irg_walk_func *pre, irg_walk_func *post,
+                                void *env) {
+	int i, n;
+
+	if (!Block_block_visited(bl)) {
+		mark_Block_block_visited(bl);
+
+		if (pre)
+			pre(bl, env);
+
+		for (i = 0, n =  get_Block_n_cfg_outs(bl); i < n; ++i) {
+			/* find the corresponding predecessor block. */
+			ir_node *pred = get_Block_cfg_out(bl, i);
+			/* recursion */
+			irg_out_block_walk2(pred, pre, post, env);
+		}
+
+		if (post)
+			post(bl, env);
+	}
 }
 
 /* Walks only over Block nodes in the graph.  Has it's own visited
    flag, so that it can be interleaved with the other walker.         */
 void irg_out_block_walk(ir_node *node,
-            irg_walk_func *pre, irg_walk_func *post,
-            void *env) {
-
-  assert((get_irn_op(node) == op_Block) || (get_irn_mode(node) == mode_X));
+                        irg_walk_func *pre, irg_walk_func *post,
+                        void *env) {
 
-  inc_irg_block_visited(current_ir_graph);
+	assert(is_Block(node) || (get_irn_mode(node) == mode_X));
 
-  if (get_irn_mode(node) == mode_X) node = node->out[1];
+	inc_irg_block_visited(current_ir_graph);
 
-  irg_out_block_walk2(node, pre, post, env);
-
-  return;
+	if (get_irn_mode(node) == mode_X) {
+		int i, n;
 
+		for (i = 0, n = get_irn_n_outs(node); i < n; ++i) {
+			ir_node *succ = get_irn_out(node, i);
+			if (get_irn_visited(succ) < get_irg_visited(current_ir_graph))
+				irg_out_walk_2(succ, pre, post, env);
+		}
+	}
+	else {
+		irg_out_block_walk2(node, pre, post, env);
+	}
 }
 
 /*--------------------------------------------------------------------*/
-/** Building and Removing the out datasturcture                      **/
+/** Building and Removing the out datastructure                      **/
 /**                                                                  **/
 /** The outs of a graph are allocated in a single, large array.      **/
 /** This allows to allocate and deallocate the memory for the outs   **/
@@ -212,90 +297,103 @@ void irg_out_block_walk(ir_node *node,
 
 /** Returns the amount of out edges for not yet visited successors. */
 static int _count_outs(ir_node *n) {
-  int start, i, res, irn_arity;
+	int start, i, res, irn_arity;
+
+	mark_irn_visited(n);
+	n->out = INT_TO_PTR(1);     /* Space for array size. */
 
-  set_irn_visited(n, get_irg_visited(current_ir_graph));
-  n->out = (ir_node **) 1;     /* Space for array size. */
+	start = is_Block(n) ? 0 : -1;
+	irn_arity = get_irn_arity(n);
+	res = irn_arity - start + 1;  /* --1 or --0; 1 for array size. */
 
-  start = is_Block(n) ? 0 : -1;
-  irn_arity = get_irn_arity(n);
-  res = irn_arity - start + 1;  /* --1 or --0; 1 for array size. */
+	for (i = start; i < irn_arity; ++i) {
+		/* Optimize Tuples.  They annoy if walking the cfg. */
+		ir_node *pred         = get_irn_n(n, i);
+		ir_node *skipped_pred = skip_Tuple(pred);
 
-  for (i = start; i < irn_arity; i++) {
-    /* Optimize Tuples.  They annoy if walking the cfg. */
-    ir_node *succ = skip_Tuple(get_irn_n(n, i));
-    set_irn_n(n, i, succ);
+		if (skipped_pred != pred) {
+			set_irn_n(n, i, skipped_pred);
+		}
 
-    /* count outs for successors */
-    if (get_irn_visited(succ) < get_irg_visited(current_ir_graph)) {
-      res += _count_outs(succ);
-    }
-    /* Count my outs */
-    succ->out = (ir_node **)( (int)succ->out + 1);
-  }
-  return res;
+		/* count Def-Use edges for predecessors */
+		if (irn_not_visited(skipped_pred))
+			res += _count_outs(skipped_pred);
+
+		/*count my Def-Use edges */
+		skipped_pred->out = INT_TO_PTR(PTR_TO_INT(skipped_pred->out) + 1);
+	}
+	return res;
 }
 
 
 /** Returns the amount of out edges for not yet visited successors.
- *  This version handles some special nodes like irg_frame etc.
+ *  This version handles some special nodes like irg_frame, irg_args etc.
  */
 static int count_outs(ir_graph *irg) {
-  ir_node *n;
-  int res;
-
-  inc_irg_visited(irg);
-  res = _count_outs(get_irg_end(irg));
-
-  /* now handle special nodes */
-  n = get_irg_frame(irg);
-  if (get_irn_visited(n) < get_irg_visited(current_ir_graph)) {
-    n->out = (ir_node **)1;
-    ++res;
-  }
-
-  return res;
+	ir_node *n;
+	int     i, res;
+
+	inc_irg_visited(irg);
+	res = _count_outs(get_irg_end(irg));
+
+	/* Now handle anchored nodes. We need the out count of those
+	   even if they are not visible. */
+	for (i = anchor_last - 1; i >= 0; --i) {
+		n = get_irg_anchor(irg, i);
+		if (irn_not_visited(n)) {
+			mark_irn_visited(n);
+
+			n->out = INT_TO_PTR(1);
+			++res;
+		}
+	}
+	return res;
 }
 
 /**
  * Enter memory for the outs to a node.
  *
- * @param n      current node
+ * @param use    current node
  * @param free   current free address in the chunk allocated for the outs
  *
  * @return The next free address
  */
-static ir_node **_set_out_edges(ir_node *n, ir_node **free) {
-  int n_outs, start, i, irn_arity;
-  ir_node *succ;
+static ir_def_use_edge *_set_out_edges(ir_node *use, ir_def_use_edge *free) {
+	int     n_outs, start, i, irn_arity, pos;
 
-  set_irn_visited(n, get_irg_visited(current_ir_graph));
+	mark_irn_visited(use);
 
-  /* Allocate my array */
-  n_outs = (int) n->out;
-  n->out = free;
+	/* Allocate my array */
+	n_outs = PTR_TO_INT(use->out);
+	use->out = free;
 #ifdef DEBUG_libfirm
-  n->out_valid = 1;
+	use->out_valid = 1;
 #endif /* defined DEBUG_libfirm */
-  free += n_outs;
-  /* We count the successors again, the space will be sufficient.
-     We use this counter to remember the position for the next back
-     edge. */
-  n->out[0] = (ir_node *)0;
-
-  start = is_Block(n) ? 0 : -1;
-  irn_arity = get_irn_arity(n);
-
-  for (i = start; i < irn_arity; i++) {
-    succ = get_irn_n(n, i);
-    /* Recursion */
-    if (get_irn_visited(succ) < get_irg_visited(current_ir_graph))
-      free = _set_out_edges(succ, free);
-    /* Remember our back edge */
-    succ->out[get_irn_n_outs(succ)+1] = n;
-    succ->out[0] = (ir_node *) (get_irn_n_outs(succ) + 1);
-  }
-  return free;
+	free += n_outs;
+	/* We count the successors again, the space will be sufficient.
+	   We use this counter to remember the position for the next back
+	   edge. */
+	use->out[0].pos = 0;
+
+	start = is_Block(use) ? 0 : -1;
+	irn_arity = get_irn_arity(use);
+
+	for (i = start; i < irn_arity; ++i) {
+		ir_node *def = get_irn_n(use, i);
+
+		/* Recursion */
+		if (irn_not_visited(def))
+			free = _set_out_edges(def, free);
+
+		/* Remember this Def-Use edge */
+		pos = def->out[0].pos + 1;
+		def->out[pos].use = use;
+		def->out[pos].pos = i;
+
+		/* increase the number of Def-Use edges so far */
+		def->out[0].pos = pos;
+	}
+	return free;
 }
 
 /**
@@ -306,91 +404,113 @@ static ir_node **_set_out_edges(ir_node *n, ir_node **free) {
  *
  * @return The next free address
  */
-static ir_node **set_out_edges(ir_graph *irg, ir_node **free) {
-  ir_node *n;
-  int n_outs;
+static ir_def_use_edge *set_out_edges(ir_graph *irg, ir_def_use_edge *free) {
+	ir_node *n;
+	int     i, n_outs;
 
-  inc_irg_visited(irg);
-  free = _set_out_edges(get_irg_end(irg), free);
+	inc_irg_visited(irg);
+	free = _set_out_edges(get_irg_end(irg), free);
 
-  n = get_irg_frame(irg);
-  if (get_irn_visited(n) < get_irg_visited(current_ir_graph)) {
-    n_outs = (int)n->out;
-    n->out = free;
+	/* handle anchored nodes */
+	for (i = anchor_last - 1; i >= 0; --i) {
+		n = get_irg_anchor(irg, i);
+		if (irn_not_visited(n)) {
+			mark_irn_visited(n);
+
+			n_outs = PTR_TO_INT(n->out);
+			n->out = free;
 #ifdef DEBUG_libfirm
-    n->out_valid = 1;
+			n->out_valid = 1;
 #endif /* defined DEBUG_libfirm */
-    free += n_outs;
-  }
+			free += n_outs;
+		}
+	}
 
-  return free;
+	return free;
 }
 
 
-/* We want that the out of ProjX from Start contains the next block at
-   position 1, the Start block at position 2.  This is necessary for
-   the out block walker. */
+/**
+ * We want that the out of ProjX from Start contains the next block at
+ * position 0, the Start block at position 1.  This is necessary for
+ * the out block walker.
+ */
 static INLINE void fix_start_proj(ir_graph *irg) {
-  ir_node *proj    = NULL;
-  ir_node *startbl = get_irg_start_block(irg);
-  int i;
-
-  if (get_Block_n_cfg_outs(startbl)) {
-    for (i = 0; i < get_irn_n_outs(startbl); i++)
-      if (get_irn_mode(get_irn_out(startbl, i)) == mode_X) {
-        proj = get_irn_out(startbl, i);
-        break;
-      }
-
-    if (get_irn_out(proj, 0) == startbl) {
-      assert(get_irn_n_outs(proj) == 2);
-      set_irn_out(proj, 0, get_irn_out(proj, 1));
-      set_irn_out(proj, 1, startbl);
-    }
-  }
+	ir_node *startbl = get_irg_start_block(irg);
+
+	if (get_Block_n_cfg_outs(startbl)) {
+		ir_node *proj = get_irg_initial_exec(irg);
+		ir_node *irn;
+		int     block_pos, other_pos;
+
+		if (get_irn_n_outs(proj) == 2) {
+			if (get_irn_out_ex(proj, 0, &block_pos) == startbl) {
+				irn = get_irn_out_ex(proj, 1, &other_pos);
+				set_irn_out(proj, 0, irn, other_pos);
+				set_irn_out(proj, 1, startbl, block_pos);
+			}
+		} else {
+			assert(get_irg_phase_state(irg) == phase_backend);
+		}
+	}
 }
 
 /* compute the outs for a given graph */
-void compute_outs(ir_graph *irg) {
-  ir_graph *rem = current_ir_graph;
-  int n_out_edges = 0;
-  ir_node **end = NULL;         /* Only for debugging */
+void compute_irg_outs(ir_graph *irg) {
+	ir_graph        *rem = current_ir_graph;
+	int             n_out_edges = 0;
+	ir_def_use_edge *end = NULL;         /* Only for debugging */
 
-  current_ir_graph = irg;
+	current_ir_graph = irg;
 
-  /* Update graph state */
-  assert(get_irg_phase_state(current_ir_graph) != phase_building);
+	/* Update graph state */
+	assert(get_irg_phase_state(current_ir_graph) != phase_building);
 
-  if (current_ir_graph->outs_state != outs_none)
-    free_outs(current_ir_graph);
-  current_ir_graph->outs_state = outs_consistent;
+	if (current_ir_graph->outs_state != outs_none)
+		free_irg_outs(current_ir_graph);
 
-  /* This first iteration counts the overall number of out edges and the
-     number of out edges for each node. */
-  n_out_edges = count_outs(irg);
+	/* This first iteration counts the overall number of out edges and the
+	   number of out edges for each node. */
+	n_out_edges = count_outs(irg);
 
-  /* allocate memory for all out edges. */
-  irg->outs = xcalloc(n_out_edges, sizeof(irg->outs[0]));
+	/* allocate memory for all out edges. */
+	irg->outs = xcalloc(n_out_edges, sizeof(irg->outs[0]));
 #ifdef DEBUG_libfirm
-  irg->n_outs = n_out_edges;
+	irg->n_outs = n_out_edges;
 #endif /* defined DEBUG_libfirm */
 
-  /* The second iteration splits the irg->outs array into smaller arrays
-     for each node and writes the back edges into this array. */
-  end = set_out_edges(irg, irg->outs);
+	/* The second iteration splits the irg->outs array into smaller arrays
+	   for each node and writes the back edges into this array. */
+	end = set_out_edges(irg, irg->outs);
 
-  /* Check how much memory we have used */
-  assert (end == (irg->outs + n_out_edges));
+	/* Check how much memory we have used */
+	assert (end == (irg->outs + n_out_edges));
 
-  /* We want that the out of ProjX from Start contains the next block at
-     position 1, the Start block at position 2.  This is necessary for
-     the out block walker. */
-  fix_start_proj(irg);
+	/* We want that the out of ProjX from Start contains the next block at
+	   position 0, the Start block at position 1.  This is necessary for
+	   code placement (place_early() ONLY if started GCSE on graphs with dead blocks) */
+	fix_start_proj(irg);
 
-  current_ir_graph = rem;
+	current_ir_graph->outs_state = outs_consistent;
+	current_ir_graph = rem;
 }
 
+void assure_irg_outs(ir_graph *irg) {
+	if (get_irg_outs_state(irg) != outs_consistent)
+		compute_irg_outs(irg);
+}
 
+void compute_irp_outs(void) {
+	int i;
+	for (i = get_irp_n_irgs() -1; i >= 0; --i)
+		compute_irg_outs(get_irp_irg(i));
+}
+
+void free_irp_outs(void) {
+	int i;
+	for (i = get_irp_n_irgs() -1; i >= 0; --i)
+		free_irg_outs(get_irp_irg(i));
+}
 
 
 /*------------------------------------------------------------*
@@ -402,12 +522,14 @@ void compute_outs(ir_graph *irg) {
  *------------------------------------------------------------*/
 
 
+#ifdef INTERPROCEDURAL_VIEW
 /**
  * Inits the number of outedges for each node
  * before counting.
  */
 static void init_count(ir_node * node, void *env) {
-  node->out = (ir_node **) 1; /* 1 for the array size */
+	(void) env;
+	node->out = (ir_node **) 1; /* 1 for the array size */
 }
 
 
@@ -416,35 +538,32 @@ static void init_count(ir_node * node, void *env) {
  * and adds the current arity to the overall count,
  * which is saved in "env"
  */
-static void node_arity_count(ir_node * node, void * env)
-{
-  int *anz = (int *) env, arity, n_outs, i, start;
-  ir_node *succ;
+static void node_arity_count(ir_node * node, void * env) {
+	int *anz = (int *) env, arity, n_outs, i, start;
+	ir_node *succ;
 
-  arity = get_irn_arity(node);
-  start = (is_Block(node)) ? 0 : -1;
+	arity = get_irn_arity(node);
+	start = (is_Block(node)) ? 0 : -1;
 
-  n_outs = 1 + arity + (-start);  // ((is_Block(node)) ? 0 : 1);   // Why + 1??
-  *anz += n_outs;
+	n_outs = 1 + arity + (-start);  // ((is_Block(node)) ? 0 : 1);   // Why + 1??
+	*anz += n_outs;
 
-  for(i = start; i < arity; i++) {
-    succ = get_irn_n(node, i);
-    succ->out = (ir_node **)((int)succ->out + 1);
-  }
+	for(i = start; i < arity; i++) {
+		succ = get_irn_n(node, i);
+		succ->out = (ir_node **)INT_TO_PTR(PTR_TO_INT(succ->out) + 1);
+	}
 }
 
-
 /*
  * Inits all nodes for setting the outedges
  * Returns the overall count of edges
  */
 int count_ip_outs(void) {
+	int res = 0;
 
-  int res = 0;
+	cg_walk(init_count, node_arity_count, &res);
 
-  cg_walk(init_count, node_arity_count, &res);
-
-  return(res);
+	return(res);
 }
 
 static int dummy_count = 0, global_count; /* Only for debugging */
@@ -455,20 +574,19 @@ static int dummy_count = 0, global_count; /* Only for debugging */
  * The current array start is transported in env
  */
 static void set_array_pointer(ir_node *node, void *env) {
-
-  int n_outs;
-  ir_node ***free = (ir_node ***) env;
-
-  /* Allocate my array */
-  n_outs = (int) node -> out;  /* We wrote the count here in count_ip_outs */
-  dummy_count += n_outs;
-  assert(dummy_count <= global_count && "More outedges than initially counted!");
-  node -> out = *free;
-  *free = &((*free)[n_outs]);
-  /* We count the successors again, the space will be sufficient.
-     We use this counter to remember the position for the next back
-     edge. */
-  node -> out[0] = (ir_node *) 0;
+	int n_outs;
+	ir_node ***free = (ir_node ***) env;
+
+	/* Allocate my array */
+	n_outs = PTR_TO_INT(node->out);  /* We wrote the count here in count_ip_outs */
+	dummy_count += n_outs;
+	assert(dummy_count <= global_count && "More outedges than initially counted!");
+	node -> out = *free;
+	*free = &((*free)[n_outs]);
+	/* We count the successors again, the space will be sufficient.
+	   We use this counter to remember the position for the next back
+	   edge. */
+	node -> out[0] = (ir_node *) 0;
 }
 
 
@@ -476,26 +594,26 @@ static void set_array_pointer(ir_node *node, void *env) {
  * Adds an outedge from the predecessor to the
  * current node.
  */
-static void set_out_pointer(ir_node * node, void * env) {
-  int i, arity = get_irn_arity(node);
-  ir_node *succ;
-  int start = (!is_Block(node)) ? -1 : 0;
-
-  for(i = start; i < arity; i++) {
-    succ = get_irn_n(node, i);
-    succ->out[get_irn_n_outs(succ)+1] = node;
-    succ->out[0] = (ir_node *) (get_irn_n_outs(succ) + 1);
-  }
+static void set_out_pointer(ir_node * node, void *env) {
+	int i, arity = get_irn_arity(node);
+	ir_node *succ;
+	int start = (!is_Block(node)) ? -1 : 0;
+	(void) env;
+
+	for (i = start; i < arity; ++i) {
+		succ = get_irn_n(node, i);
+		succ->out[get_irn_n_outs(succ)+1] = node;
+		succ->out[0] = INT_TO_PTR(get_irn_n_outs(succ) + 1);
+	}
 }
 
 
 /*
  * Sets the outedges for all nodes.
  */
-void set_ip_outs(void)
-{
-  ir_node **outedge_array = get_irp_ip_outedges();
-  cg_walk(set_array_pointer, set_out_pointer, (void *) &outedge_array);
+void set_ip_outs(void) {
+	ir_node **outedge_array = get_irp_ip_outedges();
+	cg_walk(set_array_pointer, set_out_pointer, (void *) &outedge_array);
 }
 
 
@@ -506,53 +624,94 @@ void set_ip_outs(void)
  * view!
  */
 void compute_ip_outs(void) {
+	int n_out_edges;
+	ir_node **out_edges;
 
-  int n_out_edges;
-  ir_node **out_edges;
-
-  assert(get_irp_ip_view_state() == ip_view_valid &&
-     "Cannot construct outs for invalid ip view.");
+	assert(get_irp_ip_view_state() == ip_view_valid &&
+	 "Cannot construct outs for invalid ip view.");
 
-  if (irp->outs_state != outs_none) {
-    free_ip_outs();
-  }
+	if (irp->outs_state != outs_none) {
+		free_ip_outs();
+	}
 
-  global_count = n_out_edges = count_ip_outs();
-  out_edges = xcalloc(n_out_edges, sizeof(out_edges[0]));
-  set_irp_ip_outedges(out_edges);
-  set_ip_outs();
+	global_count = n_out_edges = count_ip_outs();
+	out_edges = xcalloc(n_out_edges, sizeof(out_edges[0]));
+	set_irp_ip_outedges(out_edges);
+	set_ip_outs();
 }
 
-void free_ip_outs(void)
-{
-  ir_node **out_edges = get_irp_ip_outedges();
-  if (out_edges != NULL) {
-    free(out_edges);
-    set_irp_ip_outedges(NULL);
-  }
-  irp->outs_state = outs_none;
+void free_ip_outs(void) {
+	ir_node **out_edges = get_irp_ip_outedges();
+	if (out_edges != NULL) {
+		free(out_edges);
+		set_irp_ip_outedges(NULL);
+	}
+	irp->outs_state = outs_none;
 }
+#endif
 
 
-void free_outs(ir_graph *irg) {
-
-  /*   current_ir_graph->outs_state = outs_none; */
-  irg->outs_state = outs_none;
+void free_irg_outs(ir_graph *irg) {
+	/*   current_ir_graph->outs_state = outs_none; */
+	irg->outs_state = outs_none;
 
-  if (irg->outs) {
+	if (irg->outs) {
 #ifdef DEBUG_libfirm
-    memset(irg->outs, 0, irg->n_outs);
+		memset(irg->outs, 0, irg->n_outs);
 #endif /* defined DEBUG_libfirm */
-    free(irg->outs);
-    irg->outs = NULL;
+		free(irg->outs);
+		irg->outs = NULL;
 #ifdef DEBUG_libfirm
-    irg->n_outs = 0;
+		irg->n_outs = 0;
 #endif /* defined DEBUG_libfirm */
-  }
+	}
 
 #ifdef DEBUG_libfirm
-  /* when debugging, *always* reset all nodes' outs!  irg->outs might
-     have been lying to us */
-  irg_walk_graph (irg, reset_outs, NULL, NULL);
+	/* when debugging, *always* reset all nodes' outs!  irg->outs might
+	   have been lying to us */
+	irg_walk_graph (irg, reset_outs, NULL, NULL);
 #endif /* defined DEBUG_libfirm */
 }
+
+static void check_out_edges(ir_node *irn, void *env) {
+	int i, j, pos;
+	int *pError = env;
+	int error = *pError;
+	int last = is_Block(irn) ? 0 : -1;
+
+	/* check forward: every input must have an out edge */
+	for (i = get_irn_arity(irn) - 1; i >= last; --i) {
+		ir_node *pred = get_irn_n(irn, i);
+
+		for (j = get_irn_n_outs(pred) - 1; j >= 0; --j) {
+			ir_node *user = get_irn_out_ex(pred, j, &pos);
+
+			if (user == irn && pos == i) {
+				break;
+			}
+		}
+		if (j < 0) {
+			ir_fprintf(stderr, "Missing out edge from %+F input %d to %+F", irn, i, pred);
+			++error;
+		}
+	}
+
+	/* checking backward */
+	for (i = get_irn_n_outs(irn) - 1; i >= 0; --i) {
+		ir_node *user = get_irn_out_ex(irn, i, &pos);
+
+		if (get_irn_n(user, pos) != irn) {
+			ir_fprintf(stderr, "Spurious out edge from %+F output %d to %+F", irn, i, user);
+			++error;
+		}
+	}
+	*pError = error;
+}
+
+/* verify outs edges. */
+void verify_outs(ir_graph *irg) {
+	int errors = 0;
+	irg_walk_graph(irg, NULL, check_out_edges, &errors);
+	if (errors > 0)
+		panic("Out edges are corrupt");
+}