X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Firgwalk.c;h=cf111f3fbe2d00ea131060d1330d6bfd8bdfee10;hb=94af5ee1dc6e88b9a97d2d0b2985d64025881617;hp=8b84a24a3f05a61a1c4287bd8513201a9272b964;hpb=5470b27c201e3fd91f5af86753dd55806277edcb;p=libfirm

diff --git a/ir/ir/irgwalk.c b/ir/ir/irgwalk.c
index 8b84a24a3..cf111f3fb 100644
--- a/ir/ir/irgwalk.c
+++ b/ir/ir/irgwalk.c
@@ -1,41 +1,53 @@
-/* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
-** All rights reserved.
-**
-** Author: Boris Boesler
-**
-** traverse an ir graph
-** - execute the pre function before recursion
-** - execute the post function after recursion
+/*
+ * Project:     libFIRM
+ * File name:   ir/ir/irgwalk.c
+ * Purpose:
+ * Author:      Boris Boesler
+ * Modified by: Goetz Lindenmaier
+ * Created:
+ * CVS-ID:      $Id$
+ * Copyright:   (c) 1999-2003 Universität Karlsruhe
+ * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
+ */
+
+/**
+* traverse an ir graph
+* - execute the pre function before recursion
+* - execute the post function after recursion
 */
 
-/* $Id$ */
 
 #ifdef HAVE_CONFIG_H
 # include <config.h>
 #endif
 
-# include <stdlib.h>
+#include <stdlib.h>
 
-# include "irnode.h"
-# include "irgraph.h" /* visited flag */
-# include "irprog.h"
-# include "irgwalk.h"
+#include "irnode_t.h"
+#include "irgraph_t.h" /* visited flag */
+#include "irprog.h"
+#include "irgwalk.h"
+#include "typewalk.h"
+#include "firmstat.h"
+#include "ircgcons.h"
 
-# include "eset.h"
-# include "array.h"
+#include "eset.h"
+#include "array.h"
 
 /* walk over an interprocedural graph (callgraph). Visits only graphs in irg_set. */
 static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
-			irg_walk_func pre, irg_walk_func post, void * env) {
+                        irg_walk_func *pre, irg_walk_func *post, void * env) {
   int i;
   ir_graph * rem = current_ir_graph;
   ir_node * pred;
 
-  assert(node);
+  assert(node && node->kind == k_ir_node);
   if (get_irn_visited(node) >= visited) return;
 
   set_irn_visited(node, visited);
 
+  if (pre) pre(node, env);
+
   pred = skip_Proj(node);
   if (get_irn_op(pred) == op_CallBegin
       || get_irn_op(pred) == op_EndReg
@@ -43,40 +55,45 @@ static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
     current_ir_graph = get_irn_irg(pred);
   }
 
-  if (pre) pre(node, env);
-
-  if (is_no_Block(node)) irg_walk_cg(get_nodes_Block(node), visited, irg_set, pre, post, env);
+  if (is_no_Block(node)) { /* not block */
+    irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
+  }
 
   if (get_irn_op(node) == op_Block) { /* block */
     for (i = get_irn_arity(node) - 1; i >= 0; --i) {
       ir_node * exec = get_irn_n(node, i);
       ir_node * pred = skip_Proj(exec);
       if ((get_irn_op(pred) != op_CallBegin
-	   && get_irn_op(pred) != op_EndReg
-	   && get_irn_op(pred) != op_EndExcept)
-	  || eset_contains(irg_set, get_irn_irg(pred))) {
-	irg_walk_cg(exec, visited, irg_set, pre, post, env);
+           && get_irn_op(pred) != op_EndReg
+           && get_irn_op(pred) != op_EndExcept)
+          || eset_contains(irg_set, get_irn_irg(pred))) {
+        irg_walk_cg(exec, visited, irg_set, pre, post, env);
       }
     }
-  } else if (get_irn_op(node) == op_Filter) {
+  } else if (get_irn_op(node) == op_Filter) { /* filter */
     for (i = get_irn_arity(node) - 1; i >= 0; --i) {
       ir_node * pred = get_irn_n(node, i);
       if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
-	irg_walk_cg(pred, visited, irg_set, pre, post, env);
+        irg_walk_cg(pred, visited, irg_set, pre, post, env);
       } else {
-	ir_node * exec;
-	exec = skip_Proj(get_Block_cfgpred(get_nodes_Block(node), i));
-	assert(get_irn_op(exec) == op_CallBegin
-	       || get_irn_op(exec) == op_EndReg
-	       || get_irn_op(exec) == op_EndExcept);
-	if (eset_contains(irg_set, get_irn_irg(exec))) {
-	  current_ir_graph = get_irn_irg(exec);
-	  irg_walk_cg(pred, visited, irg_set, pre, post, env);
-	  current_ir_graph = rem;
-	}
+        ir_node * exec;
+        exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
+
+        if (op_Bad == get_irn_op (exec)) {
+          continue;
+        }
+
+        assert(get_irn_op(exec) == op_CallBegin
+               || get_irn_op(exec) == op_EndReg
+               || get_irn_op(exec) == op_EndExcept);
+        if (eset_contains(irg_set, get_irn_irg(exec))) {
+          current_ir_graph = get_irn_irg(exec);
+          irg_walk_cg(pred, visited, irg_set, pre, post, env);
+          current_ir_graph = rem;
+        }
       }
     }
-  } else {
+  } else {                      /* everything else */
     for (i = get_irn_arity(node) - 1; i >= 0; --i) {
       irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
     }
@@ -96,65 +113,116 @@ static void collect_irgs(ir_node * node, eset * irg_set) {
       entity * ent = get_Call_callee(node, i);
       ir_graph * irg = ent ? get_entity_irg(ent) : NULL;
       if (irg && !eset_contains(irg_set, irg)) {
-	eset_insert(irg_set, irg);
-	irg_walk_graph(irg, (irg_walk_func) collect_irgs, NULL, irg_set);
+        eset_insert(irg_set, irg);
+        irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
       }
     }
   }
 }
 
-
-void irg_walk_2(ir_node *node, irg_walk_func pre, irg_walk_func post, void * env)
-{
+/**
+ * specialized version of irg_walk_2, called if only pre callback exists
+ */
+static void
+irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
   int i;
+  set_irn_visited(node, current_ir_graph->visited);
 
+  pre(node, env);
 
-  assert(node);
-  /*      printf(" - "); DDMSG2(node);  */
+  if (node->op != op_Block) {
+    ir_node *pred = get_irn_n(node, -1);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_pre(pred, pre, env);
+  }
+  for (i = get_irn_arity(node) - 1; i >= 0; --i) {
+    ir_node *pred = get_irn_n(node, i);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_pre(pred, pre, env);
+  }
+}
 
-  if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
+/**
+ * specialized version of irg_walk_2, called if only post callback exists
+ */
+static void
+irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
+  int i;
+  set_irn_visited(node, current_ir_graph->visited);
 
-/*      printf(" -> "); DDMSG2(node);  */
-    set_irn_visited(node, get_irg_visited(current_ir_graph));
+  if (node->op != op_Block) {
+    ir_node *pred = get_irn_n(node, -1);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_post(pred, post, env);
+  }
+  for (i = get_irn_arity(node) - 1; i >= 0; --i) {
+    ir_node *pred = get_irn_n(node, i);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_post(pred, post, env);
+  }
 
-    if (pre) {
-      pre(node, env);
-    }
+  post(node, env);
+}
 
-    if (is_no_Block(node)) {
-      irg_walk_2(get_nodes_Block(node), pre, post, env);
-    }
-    for (i = get_irn_arity(node) - 1; i >= 0; --i) {
-      /* printf("   "); DDMSG2(node);
-	 printf("   "); DDMSG2(get_irn_n(node, i));  */
+/**
+ * specialized version of irg_walk_2, called if pre and post callbacks exist
+ */
+static void
+irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
+  int i;
+  set_irn_visited(node, current_ir_graph->visited);
 
-      irg_walk_2(get_irn_n(node, i), pre, post, env);
-    }
+  pre(node, env);
 
-/*      printf(" <- "); DDMSG2(node);  */
-    if (post)
-      post(node, env);
+  if (node->op != op_Block) {
+    ir_node *pred = get_irn_n(node, -1);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_both(pred, pre, post, env);
   }
-  return;
+  for (i = get_irn_arity(node) - 1; i >= 0; --i) {
+    ir_node *pred = get_irn_n(node, i);
+    if (pred->visited < current_ir_graph->visited)
+      irg_walk_2_both(pred, pre, post, env);
+  }
+
+  post(node, env);
 }
 
+/**
+ * Intraprozedural graph walker.
+ */
+static void
+irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
+{
+  if (node->visited < current_ir_graph->visited) {
+    if      (!post) irg_walk_2_pre (node, pre, env);
+    else if (!pre)  irg_walk_2_post(node, post, env);
+    else            irg_walk_2_both(node, pre, post, env);
+  }
+}
 
-void irg_walk(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env)
+/*
+ * generic graph walker
+ */
+void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
 {
-  assert(node);
+  assert(node  && node->kind==k_ir_node);
+
   if (interprocedural_view) {
     eset * irg_set = eset_create();
     int visited;
     ir_graph * irg;
+    assert(get_irp_ip_view_state() == ip_view_valid);
+
     interprocedural_view = false;
     eset_insert(irg_set, current_ir_graph);
-    irg_walk(node, (irg_walk_func) collect_irgs, NULL, irg_set);
+    irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
     interprocedural_view = true;
     visited = get_max_irg_visited() + 1;
-    irg_walk_cg(node, visited, irg_set, pre, post, env);
     for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
       set_irg_visited(irg, visited);
     }
+    irg_walk_cg(node, visited, irg_set, pre, post, env);
     eset_destroy(irg_set);
   } else {
     inc_irg_visited(current_ir_graph);
@@ -164,20 +232,19 @@ void irg_walk(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env)
 }
 
 
-void irg_walk_graph(ir_graph *irg, irg_walk_func pre, irg_walk_func post, void *env) {
+void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
   ir_graph * rem = current_ir_graph;
+
+  stat_irg_walk(irg, (void *)pre, (void *)post);
   current_ir_graph = irg;
   irg_walk(get_irg_end(irg), pre, post, env);
   current_ir_graph = rem;
 }
 
-
-/***************************************************************************/
-
 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
    Sets current_ir_graph properly for each walk.  Conserves current
    current_ir_graph. */
-void all_irg_walk(irg_walk_func pre, irg_walk_func post, void *env) {
+void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
   int i;
   ir_graph *irg, *rem;
 
@@ -191,57 +258,155 @@ void all_irg_walk(irg_walk_func pre, irg_walk_func post, void *env) {
   current_ir_graph = rem;
 }
 
+/***************************************************************************/
+
+/* Returns current_ir_graph and sets it to the irg of predecessor index
+   of node n. */
+static INLINE ir_graph *
+switch_irg (ir_node *n, int index) {
+  ir_graph *old_current = current_ir_graph;
+
+  if (interprocedural_view) {
+    /* Only Filter and Block nodes can have predecessors in other graphs. */
+    if (get_irn_op(n) == op_Filter)
+      n = get_nodes_block(n);
+    if (get_irn_op(n) == op_Block) {
+      ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
+      if (is_ip_cfop(cfop)) {
+    current_ir_graph = get_irn_irg(cfop);
+      }
+    }
+  }
+
+  return old_current;
+}
+
+static void
+cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
+{
+  int i;
+  ir_graph *rem = NULL;
+  assert(node);
+
+  if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
+    set_irn_visited(node, get_irg_visited(current_ir_graph));
+
+    if (pre) pre(node, env);
+
+    if (is_no_Block(node))
+      cg_walk_2(get_nodes_block(node), pre, post, env);
+    for (i = get_irn_arity(node) - 1; i >= 0; --i) {
+      rem = switch_irg(node, i);  /* @@@ AS: Is this wrong? We do have to
+                                             switch to the irg of the predecessor, don't we? */
+      cg_walk_2(get_irn_n(node, i), pre, post, env);
+      current_ir_graph = rem;
+    }
+
+    if (post) post(node, env);
+  }
+  return;
+}
+
+
+/* Walks all irgs in interprocedural view.  Visits each node only once. */
+void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
+  int i;
+  ir_graph *rem = current_ir_graph;
+  int rem_view = interprocedural_view;
+
+  interprocedural_view = true;
+
+  inc_max_irg_visited();
+  /* Fix all irg_visited flags */
+  for (i = 0; i < get_irp_n_irgs(); i++)
+    set_irg_visited(get_irp_irg(i), get_max_irg_visited());
+
+  /* Walk starting at unreachable procedures. Only these
+   * have End blocks visible in interprocedural view. */
+  for (i = 0; i < get_irp_n_irgs(); i++) {
+    ir_node *sb;
+    current_ir_graph = get_irp_irg(i);
+
+    sb = get_irg_start_block(current_ir_graph);
+
+    if ((get_Block_n_cfgpreds(sb) > 1) ||
+    (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
+
+    cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
+  }
+
+  /* Check whether we walked all procedures: there could be procedures
+     with cyclic calls but no call from the outside. */
+  for (i = 0; i < get_irp_n_irgs(); i++) {
+    ir_node *sb;
+    current_ir_graph = get_irp_irg(i);
+
+    /* Test start block: if inner procedure end and end block are not
+     * visible and therefore not marked. */
+    sb = get_irg_start_block(current_ir_graph);
+    if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
+      cg_walk_2(sb, pre, post, env);
+    }
+  }
+
+  /* Walk all endless loops in inner procedures.
+   * We recognize an inner procedure if the End node is not visited. */
+  for (i = 0; i < get_irp_n_irgs(); i++) {
+    ir_node *e;
+    current_ir_graph = get_irp_irg(i);
+    e = get_irg_end(current_ir_graph);
+    if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
+      int j;
+      /* Don't visit the End node. */
+      for (j = 0; j < get_End_n_keepalives(e); j++)
+    cg_walk_2(get_End_keepalive(e, j), pre, post, env);
+    }
+  }
+
+  interprocedural_view = rem_view;
+  current_ir_graph = rem;
+}
+
+
 /***************************************************************************/
 
 /* Walks back from n until it finds a real cf op. */
-ir_node *get_cf_op(ir_node *n) {
+static ir_node *get_cf_op(ir_node *n) {
   ir_node *pred;
 
   n = skip_nop(n);
   n = skip_Tuple(n);
   pred = skip_Proj(n);
   if (!(is_cfop(pred) || is_fragile_op(pred) ||
-	(get_irn_op(pred) == op_Bad)))
+    (get_irn_op(pred) == op_Bad)))
     n = get_cf_op(n);
 
   return skip_Proj(n);
 }
 
-void irg_block_walk_2(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env)
+static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
 {
   int i;
 
-  assert(get_irn_opcode(node) == iro_Block);
-
   if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
     set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
 
-    if(pre)
-      pre(node, env);
+    if(pre) pre(node, env);
 
     for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
-
       /* find the corresponding predecessor block. */
       ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
-      /* GL: I'm not sure whether this assert must go through.  There
-         could be Id chains?? Tuple/Proj .... */
-
-      assert(is_cfop(pred)
-			 || is_fragile_op(pred)
-			 || (get_irn_op(pred) == op_Bad));
-
-      pred = get_nodes_Block(pred);
+      pred = get_nodes_block(pred);
       if(get_irn_opcode(pred) == iro_Block) {
-	/* recursion */
-	irg_block_walk_2(pred, pre, post, env);
+    /* recursion */
+    irg_block_walk_2(pred, pre, post, env);
       }
       else {
-		assert(get_irn_opcode(pred) == iro_Bad);
+    assert(get_irn_opcode(pred) == iro_Bad);
       }
     }
 
-    if(post)
-      post(node, env);
+    if(post) post(node, env);
   }
   return;
 }
@@ -249,31 +414,36 @@ void irg_block_walk_2(ir_node *node, irg_walk_func pre, irg_walk_func post, void
 
 /* 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_block_walk(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env)
+void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
 {
   ir_node *block, *pred;
   int i;
 
+  stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
+
   assert(node);
   assert(!interprocedural_view);   /* interprocedural_view not implemented, because it
-				    * interleaves with irg_walk */
+                    * interleaves with irg_walk */
   inc_irg_block_visited(current_ir_graph);
-  if (is_no_Block(node)) block = get_nodes_Block(node); else block = node;
+  if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
   assert(get_irn_opcode(block)  == iro_Block);
   irg_block_walk_2(block, pre, post, env);
   /* keepalive: the endless loops ... */
-  if (get_irn_op(node) == op_End)
-    for (i = 0; i < get_irn_arity(node); i++) {
+  if (get_irn_op(node) == op_End) {
+    int arity = get_irn_arity(node);
+    for (i = 0; i < arity; i++) {
       pred = get_irn_n(node, i);
       if (get_irn_op(pred) == op_Block)
-	irg_block_walk_2(pred, pre, post, env);
+        irg_block_walk_2(pred, pre, post, env);
     }
+  }
 
   return;
 }
 
 
-void irg_block_walk_graph(ir_graph *irg, irg_walk_func pre, irg_walk_func post, void *env) {
+void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
+              irg_walk_func *post, void *env) {
   ir_graph * rem = current_ir_graph;
   current_ir_graph = irg;
   irg_block_walk(get_irg_end(irg), pre, post, env);
@@ -283,28 +453,31 @@ void irg_block_walk_graph(ir_graph *irg, irg_walk_func pre, irg_walk_func post,
 /********************************************************************/
 
 typedef struct walk_env {
-  void *pre;
-  void *post;
+  irg_walk_func *pre;
+  irg_walk_func *post;
   void *env;
 } walk_env;
 
 /* Walk to all constant expressions in this entity. */
-void walk_entity(entity *ent, void *env) {
+static void walk_entity(entity *ent, void *env)
+{
   walk_env *my_env = (walk_env *)env;
-  if (get_entity_variability(ent) != uninitialized) {
+
+  if (get_entity_variability(ent) != variability_uninitialized) {
     if (is_atomic_entity(ent)) {
       irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
-    } else {
-      int i;
-      for (i = 0; i < get_compound_ent_n_values(ent); i++) {
-	irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
-      }
+    }
+    else {
+      int i, n = get_compound_ent_n_values(ent);
+
+      for (i = 0; i < n; i++)
+        irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
     }
   }
 }
 
 /* Walks over all code in const_code_irg. */
-void walk_const_code(irg_walk_func pre, irg_walk_func post, void *env) {
+void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
   int i, j;
   walk_env my_env;
 
@@ -317,22 +490,22 @@ void walk_const_code(irg_walk_func pre, irg_walk_func post, void *env) {
   my_env.env = env;
 
   /* Walk all types that can contain constant entities.  */
-  walk_types_entities(get_glob_type(), &walk_entity, &env);
+  walk_types_entities(get_glob_type(), &walk_entity, &my_env);
   for (i = 0; i < get_irp_n_types(); i++)
-    walk_types_entities(get_irp_type(i), &walk_entity, &env);
+    walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
   for (i = 0; i < get_irp_n_irgs(); i++)
-    walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &env);
+    walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
 
   /* Walk constant array bounds. */
   for (i = 0; i < get_irp_n_types(); i++) {
     type *tp = get_irp_type(i);
     if (is_array_type(tp)) {
       for (j = 0; j < get_array_n_dimensions(tp); j++) {
-	ir_node *n;
-	n = get_array_lower_bound(tp, j);
-	if (n) irg_walk(n, pre, post, env);
-	n = get_array_upper_bound(tp, j);
-	if (n) irg_walk(n, pre, post, env);
+    ir_node *n;
+    n = get_array_lower_bound(tp, j);
+    if (n) irg_walk(n, pre, post, env);
+    n = get_array_upper_bound(tp, j);
+    if (n) irg_walk(n, pre, post, env);
       }
     }
   }
@@ -340,6 +513,53 @@ void walk_const_code(irg_walk_func pre, irg_walk_func post, void *env) {
   current_ir_graph = rem;
 }
 
+
+/********************************************************************/
+/** Walking support for interprocedural analysis                   **/
+/**                                                                **/
+/** @@@ Don't use, not operational yet, doesn't grok recursions!!  **/
+/** @@@ Header for irgwalk.h, here until it works. **/
+/**                                                                **/
+/** Interprocedural walking should not walk all predecessors of    **/
+/** all nodes.  When leaving a procedure the walker should only    **/
+/** follow the edge corresponding to the most recent entry of the  **/
+/** procedure.  The following functions use an internal stack to   **/
+/** remember the current call site of a procedure.                 **/
+/** They also set current_ir_graph correctly.                      **/
+/**                                                                **/
+/** Usage example:                                                 **/
+/**                                                                **/
+/** void init_ip_walk ();                                          **/
+/** work_on_graph(some_end_node);                                  **/
+/** void finish_ip_walk();                                         **/
+/**                                                                **/
+/** work_on_graph(ir_node *n) {                                    **/
+/**   for (i = 0; i < get_irn_arity(n); i++) {                     **/
+/**     if (...) continue;                                         **/
+/**     ir_node *m = get_irn_ip_pred(n, i);                        **/
+/**     if !m continue;                                            **/
+/**     work_on_graph(m);                                          **/
+/**     return_recur(n, i);                                        **/
+/**   }                                                            **/
+/** }                                                              **/
+/********************************************************************/
+
+/* Call for i in {0|-1 ... get_irn_arity(n)}.
+   If n is a conventional node returns the same node as get_irn_n(n, i).
+   If the predecessors of n are in the callee of the procedure n belongs
+   to, returns get_irn_n(n, i) if this node is in the callee on the top
+   of the stack, else returns NULL.
+   If the predecessors of n are in a procedure called by the procedure n
+   belongs to pushes the caller on the caller stack in the callee.
+   Sets current_ir_graph to the graph the node returned is in. */
+ir_node *get_irn_ip_pred(ir_node *n, int pos);
+
+/* If get_irn_ip_pred() returned a node (not NULL) this must be
+   called to clear up the stacks.
+   Sets current_ir_graph to the graph n is in. */
+void return_recur(ir_node *n, int pos);
+
+
 /********************************************************************/
 /** Walking support for interprocedural analysis                   **/
 /********************************************************************/
@@ -410,13 +630,13 @@ ir_node * pop_callsite(ir_graph *callee) {
 
 /* Initialization routines ******************************************/
 
-void init_ip_walk () {
+void init_ip_walk (void) {
   int i;
   for (i = 0; i < get_irp_n_irgs(); i++)
     new_callsite_stack(get_irp_irg(i));
 }
 
-void finish_ip_walk() {
+void finish_ip_walk(void) {
   int i;
   for (i = 0; i < get_irp_n_irgs(); i++)
     free_callsite_stack(get_irp_irg(i));
@@ -467,12 +687,12 @@ ir_node *get_irn_ip_pred(ir_node *n, int pos) {
     /* Find the cf_pred refering to pos. */
     ir_node *block = n;
     ir_node *cf_pred;
-    if (get_irn_opcode(n) == iro_Filter) block = get_nodes_Block(n);
+    if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
     cf_pred = skip_Proj(get_irn_n(block, pos));
 
     /* Check whether we enter or leave a procedure and act according. */
     if ((get_irn_op(cf_pred) == op_EndReg) ||
-	(get_irn_op(cf_pred) == op_EndExcept))
+    (get_irn_op(cf_pred) == op_EndExcept))
       enter_procedure(block, cf_pred, pos);
     if (get_irn_op(cf_pred) == op_CallBegin)
       if (!leave_procedure(block, cf_pred, pos)) return NULL;
@@ -499,7 +719,7 @@ re_leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
   proj = get_Block_cg_cfgpred(block, pos);
   assert(is_Proj(proj));
   callee = get_entity_irg(get_Call_callee(get_CallBegin_call(cf_pred),
-					  get_Proj_proj(proj)));
+                      get_Proj_proj(proj)));
   current_ir_graph = callee;
   push_callsite(callee, cf_pred);
 }
@@ -513,7 +733,7 @@ return_recur(ir_node *n, int pos) {
 
   /* Find the cf_pred refering to pos. */
   block = n;
-  if (get_irn_opcode(n) == iro_Filter) block = get_nodes_Block(n);
+  if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
   cf_pred = skip_Proj(get_irn_n(block, pos));
 
   /* Check whether we re_enter or re_leave a procedure and act according. */