X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbeverify.c;h=74df99fa58b7e384303f201823e9b2becc3b2d31;hb=e9924cc1137b5920e75f4b9f2e99195dce708433;hp=2a9ea71c2054f9730538097fdb1a2b4bd5ad2ff6;hpb=fd1a2c6ca51ee2b6ff838581b79cf7a3c4553e36;p=libfirm

diff --git a/ir/be/beverify.c b/ir/be/beverify.c
index 2a9ea71c2..74df99fa5 100644
--- a/ir/be/beverify.c
+++ b/ir/be/beverify.c
@@ -1,14 +1,35 @@
 /*
- * Author:    Matthias Braun
- * Date:      05.05.2006
- * Copyright: (c) Universitaet Karlsruhe
- * License:   This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
- * CVS-Id:    $Id$
+ * Copyright (C) 1995-2007 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
+ * @brief       Various verify routines that check a scheduled graph for correctness.
+ * @author      Matthias Braun
+ * @date        05.05.2006
+ * @version     $Id$
  */
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
+#include <limits.h>
+
 #include "bitset.h"
 #include "set.h"
 #include "array.h"
@@ -24,6 +45,8 @@
 #include "belive.h"
 #include "besched_t.h"
 #include "benode_t.h"
+#include "beirg_t.h"
+#include "beintlive_t.h"
 
 static int my_values_interfere(const ir_node *a, const ir_node *b);
 
@@ -90,25 +113,36 @@ static void verify_liveness_walker(ir_node *block, void *data) {
 /**
  * Start a walk over the irg and check the register pressure.
  */
-int be_verify_register_pressure(const arch_env_t *arch_env, const arch_register_class_t *cls, ir_graph *irg) {
+int be_verify_register_pressure(const be_irg_t *birg,
+                                const arch_register_class_t *cls,
+                                ir_graph *irg) {
 	be_verify_register_pressure_env_t env;
 
 	env.lv                  = be_liveness(irg);
 	env.irg                 = irg;
-	env.arch_env            = arch_env;
+	env.arch_env            = birg->main_env->arch_env;
 	env.cls                 = cls;
-	env.registers_available = arch_count_non_ignore_regs(arch_env, cls);
+	env.registers_available = env.cls->n_regs - be_put_ignore_regs(birg, env.cls, NULL);
 	env.problem_found       = 0;
 
+	be_liveness_assure_sets(env.lv);
 	irg_block_walk_graph(irg, verify_liveness_walker, NULL, &env);
 	be_liveness_free(env.lv);
 
 	return ! env.problem_found;
 }
 
+
+
+//---------------------------------------------------------------------------
+
+
+
 typedef struct be_verify_schedule_env_t_ {
-	int      problem_found;    /**< flags indicating if there was a problem */
-	ir_graph *irg;             /**< the irg to check */
+	int      problem_found;     /**< flags indicating if there was a problem */
+	bitset_t *scheduled;        /**< bitset of scheduled nodes */
+	ir_graph *irg;              /**< the irg to check */
+	const arch_env_t *arch_env; /**< the arch_env */
 } be_verify_schedule_env_t;
 
 /**
@@ -121,17 +155,43 @@ static void verify_schedule_walker(ir_node *block, void *data) {
 	int cfchange_found = 0;
 	// TODO ask arch about delay branches
 	int delay_branches = 0;
+	int last_timestep = INT_MIN;
 
 	/*
 	 * Tests for the following things:
 	 *   1. Make sure that all phi nodes are scheduled at the beginning of the block
 	 *   2. There is 1 or no control flow changing node scheduled and exactly delay_branches operations after it.
 	 *   3. No value is defined after it has been used
+	 *   4. mode_T nodes have all projs scheduled behind them followed by Keeps
+	 *       (except mode_X projs)
 	 */
 	sched_foreach(block, node) {
 		int i, arity;
+		int timestep;
 
-		// 1. Check for phis
+		// this node is scheduled
+		if(bitset_is_set(env->scheduled, get_irn_idx(node))) {
+			ir_fprintf(stderr, "Verify warning: %+F appears to be schedule twice\n");
+			env->problem_found = 1;
+		}
+		bitset_set(env->scheduled, get_irn_idx(node));
+
+		// Check that scheduled nodes are in the correct block
+		if(get_nodes_block(node) != block) {
+			ir_fprintf(stderr, "Verify warning: %+F is in block %+F but scheduled in %+F\n", node, get_nodes_block(node), block);
+			env->problem_found = 1;
+		}
+
+		// Check that timesteps are increasing
+		timestep = sched_get_time_step(node);
+		if(timestep <= last_timestep) {
+			ir_fprintf(stderr, "Verify warning: Schedule timestep did not increase at node %+F\n",
+			           node);
+			env->problem_found = 1;
+		}
+		last_timestep = timestep;
+
+		// Check that phis come before any other node
 		if (is_Phi(node)) {
 			if (non_phi_found) {
 				ir_fprintf(stderr, "Verify Warning: Phi node %+F scheduled after non-Phi nodes in block %+F (%s)\n",
@@ -142,7 +202,7 @@ static void verify_schedule_walker(ir_node *block, void *data) {
 			non_phi_found = 1;
 		}
 
-		// 2. Check for control flow changing nodes
+		// Check for control flow changing nodes
 		if (is_cfop(node) && get_irn_opcode(node) != iro_Start) {
 			/* check, that only one CF operation is scheduled */
 			if (cfchange_found == 1) {
@@ -165,7 +225,7 @@ static void verify_schedule_walker(ir_node *block, void *data) {
 			}
 		}
 
-		// 3. Check for uses
+		// Check that all uses come before their definitions
 		if(!is_Phi(node)) {
 			int nodetime = sched_get_time_step(node);
 			for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
@@ -182,12 +242,60 @@ static void verify_schedule_walker(ir_node *block, void *data) {
 			}
 		}
 
-		// 4. check for dead nodes
+		// Check that no dead nodes are scheduled
 		if(get_irn_n_edges(node) == 0) {
 			ir_fprintf(stderr, "Verify warning: Node %+F is dead but scheduled in block %+F (%s)\n",
 			           node, block, get_irg_dump_name(env->irg));
 			env->problem_found = 1;
 		}
+
+		// check that all projs/keeps are behind their nodes
+		if(is_Proj(node)) {
+			ir_node *prev = sched_prev(node);
+			while(is_Proj(prev))
+				prev = sched_prev(prev);
+			if(get_Proj_pred(node) != prev) {
+				ir_fprintf(stderr, "%+F not scheduled after its pred node in block %+F (%s)\n",
+				           node, block, get_irg_dump_name(env->irg));
+				env->problem_found = 1;
+			}
+		}
+		if(be_is_Keep(node)) {
+			int arity   = get_irn_arity(node);
+			int problem = 0;
+			for(i = 0; i < arity; ++i) {
+				ir_node *in = get_irn_n(node, i);
+				ir_node *succ = sched_next(in);
+				while(succ != node && !sched_is_end(succ)) {
+					/* the node in between has to be another input of the
+					 * keep or a Proj */
+					int i2;
+					int found = 0;
+
+					if(is_Proj(succ)) {
+						succ = sched_next(succ);
+						continue;
+					}
+
+					for(i2 = 0; i2 < arity; ++i2) {
+						ir_node *in2 = get_irn_n(node, i2);
+						if(in2 == succ) {
+							found = 1;
+							break;
+						}
+					}
+					if(!found)
+						problem = 1;
+
+					succ = sched_next(succ);
+				}
+			}
+			if(problem) {
+				ir_fprintf(stderr, "%+F not scheduled after its pred node in block %+F (%s)\n",
+				           node, block, get_irg_dump_name(env->irg));
+				env->problem_found = 1;
+			}
+		}
 	}
 
 	/* check that all delay branches are filled (at least with NOPs) */
@@ -198,18 +306,21 @@ static void verify_schedule_walker(ir_node *block, void *data) {
 	}
 }
 
-static int should_be_scheduled(ir_node *node) {
+static int should_be_scheduled(be_verify_schedule_env_t *env, ir_node *node) {
 	if(is_Block(node))
 		return -1;
 
 	if(get_irn_mode(node) == mode_M) {
 		if(is_Proj(node))
-			return -1;
-		if(is_Phi(node) || is_Sync(node) || get_irn_opcode(node) == iro_Pin)
+			return 0;
+		if(is_Phi(node) || is_Sync(node) || is_Pin(node))
 			return 0;
 	}
-	if(is_Proj(node) && get_irn_mode(node) == mode_X)
-		return 0;
+	if(is_Proj(node)) {
+		if(get_irn_mode(node) == mode_X)
+			return 0;
+		return should_be_scheduled(env, get_Proj_pred(node));
+	}
 	if(be_is_Keep(node) && get_irn_opcode(get_nodes_block(node)) == iro_Bad)
 		return 0;
 
@@ -217,23 +328,30 @@ static int should_be_scheduled(ir_node *node) {
 	case iro_End:
 	case iro_NoMem:
 	case iro_Bad:
+	case iro_Unknown:
 		return 0;
 	default:
 		break;
 	}
 
+	if(arch_irn_get_flags(env->arch_env, node) & arch_irn_flags_ignore)
+		return -1;
+
 	return 1;
 }
 
 static void check_schedule(ir_node *node, void *data) {
 	be_verify_schedule_env_t *env = data;
 	int should_be;
+	int scheduled;
 
-	should_be = should_be_scheduled(node);
+	should_be = should_be_scheduled(env, node);
 	if(should_be == -1)
 		return;
 
-	if(should_be ? !sched_is_scheduled(node) : sched_is_scheduled(node)) {
+	scheduled = bitset_is_set(env->scheduled, get_irn_idx(node)) ? 1 : 0;
+	should_be = should_be ? 1 : 0;
+	if(should_be != scheduled) {
 		ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should%s be scheduled\n",
 			node, get_nodes_block(node), get_irg_dump_name(env->irg), should_be ? "" : " not");
 		env->problem_found = 1;
@@ -243,16 +361,18 @@ static void check_schedule(ir_node *node, void *data) {
 /**
  * Start a walk over the irg and check schedule.
  */
-int be_verify_schedule(ir_graph *irg)
+int be_verify_schedule(const be_irg_t *birg)
 {
 	be_verify_schedule_env_t env;
 
 	env.problem_found = 0;
-	env.irg           = irg;
+	env.irg           = be_get_birg_irg(birg);
+	env.scheduled     = bitset_alloca(get_irg_last_idx(env.irg));
+	env.arch_env      = birg->main_env->arch_env;
 
-	irg_block_walk_graph(irg, verify_schedule_walker, NULL, &env);
+	irg_block_walk_graph(env.irg, verify_schedule_walker, NULL, &env);
 	// check if all nodes are scheduled
-	irg_walk_graph(irg, check_schedule, NULL, &env);
+	irg_walk_graph(env.irg, check_schedule, NULL, &env);
 
 	return ! env.problem_found;
 }
@@ -265,7 +385,7 @@ int be_verify_schedule(ir_graph *irg)
 
 typedef struct _spill_t {
 	ir_node *spill;
-	entity *ent;
+	ir_entity *ent;
 } spill_t;
 
 typedef struct {
@@ -279,6 +399,8 @@ typedef struct {
 static int cmp_spill(const void* d1, const void* d2, size_t size) {
 	const spill_t* s1 = d1;
 	const spill_t* s2 = d2;
+	(void) size;
+
 	return s1->spill != s2->spill;
 }
 
@@ -289,7 +411,7 @@ static spill_t *find_spill(be_verify_spillslots_env_t *env, ir_node *node) {
 	return set_find(env->spills, &spill, sizeof(spill), HASH_PTR(node));
 }
 
-static spill_t *get_spill(be_verify_spillslots_env_t *env, ir_node *node, entity *ent) {
+static spill_t *get_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_entity *ent) {
 	spill_t spill, *res;
 	int hash = HASH_PTR(node);
 
@@ -320,18 +442,21 @@ static ir_node *get_memory_edge(const ir_node *node) {
 	return result;
 }
 
-static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, entity* ent);
+static
+void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent);
 
-static void check_entity(be_verify_spillslots_env_t *env, ir_node *node, entity *ent) {
+static
+void be_check_entity(be_verify_spillslots_env_t *env, ir_node *node, ir_entity *ent) {
 	if(ent == NULL) {
 		ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have an entity assigned\n",
 		           node, get_nodes_block(node), get_irg_dump_name(env->irg));
 	}
 }
 
-static void collect_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, entity* ent) {
-	entity *spillent = arch_get_frame_entity(env->arch_env, node);
-	check_entity(env, node, spillent);
+static
+void collect_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent) {
+	ir_entity *spillent = arch_get_frame_entity(env->arch_env, node);
+	be_check_entity(env, node, spillent);
 	get_spill(env, node, ent);
 
 	if(spillent != ent) {
@@ -341,13 +466,13 @@ static void collect_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_nod
 	}
 }
 
-static void collect_memperm(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, entity* ent) {
+static void collect_memperm(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent) {
 	int i, arity;
 	spill_t spill, *res;
 	int hash = HASH_PTR(node);
 	int out;
 	ir_node* memperm;
-	entity *spillent;
+	ir_entity *spillent;
 
 	assert(is_Proj(node));
 
@@ -355,7 +480,7 @@ static void collect_memperm(be_verify_spillslots_env_t *env, ir_node *node, ir_n
 	out = get_Proj_proj(node);
 
 	spillent = be_get_MemPerm_out_entity(memperm, out);
-	check_entity(env, memperm, spillent);
+	be_check_entity(env, memperm, spillent);
 	if(spillent != ent) {
 		ir_fprintf(stderr, "Verify warning: MemPerm %+F has different entity than reload %+F in block %+F(%s)\n",
 			node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
@@ -373,13 +498,13 @@ static void collect_memperm(be_verify_spillslots_env_t *env, ir_node *node, ir_n
 
 	for(i = 0, arity = be_get_MemPerm_entity_arity(memperm); i < arity; ++i) {
 		ir_node* arg = get_irn_n(memperm, i + 1);
-		entity* argent = be_get_MemPerm_in_entity(memperm, i);
+		ir_entity* argent = be_get_MemPerm_in_entity(memperm, i);
 
 		collect(env, arg, memperm, argent);
 	}
 }
 
-static void collect_memphi(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, entity *ent) {
+static void collect_memphi(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity *ent) {
 	int i, arity;
 	spill_t spill, *res;
 	int hash = HASH_PTR(node);
@@ -402,7 +527,7 @@ static void collect_memphi(be_verify_spillslots_env_t *env, ir_node *node, ir_no
 	}
 }
 
-static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, entity* ent) {
+static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent) {
 	if(be_is_Spill(node)) {
 		collect_spill(env, node, reload, ent);
 	} else if(is_Proj(node)) {
@@ -410,9 +535,12 @@ static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *rel
 	} else if(is_Phi(node) && get_irn_mode(node) == mode_M) {
 		collect_memphi(env, node, reload, ent);
 	} else {
+		// Disabled for now, spills might get transformed by the backend
+#if 0
 		ir_fprintf(stderr, "Verify warning: No spill, memperm or memphi attached to node %+F found from node %+F in block %+F(%s)\n",
 			node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
 		env->problem_found = 1;
+#endif
 	}
 }
 
@@ -430,7 +558,7 @@ static void collect_spills_walker(ir_node *node, void *data) {
 
 	if(arch_irn_class_is(arch_env, node, reload)) {
 		ir_node *spill = get_memory_edge(node);
-		entity *ent;
+		ir_entity *ent;
 
 		if(spill == NULL) {
 			ir_fprintf(stderr, "Verify warning: No spill attached to reload %+F in block %+F(%s)\n",
@@ -439,7 +567,7 @@ static void collect_spills_walker(ir_node *node, void *data) {
 			return;
 		}
 		ent = arch_get_frame_entity(env->arch_env, node);
-		check_entity(env, node, ent);
+		be_check_entity(env, node, ent);
 
 		collect(env, spill, node, ent);
 		ARR_APP1(ir_node*, env->reloads, node);
@@ -483,8 +611,8 @@ static void check_lonely_spills(ir_node *node, void *data) {
 	if(be_is_Spill(node) || (is_Proj(node) && be_is_MemPerm(get_Proj_pred(node)))) {
 		spill_t *spill = find_spill(env, node);
 		if(be_is_Spill(node)) {
-			entity *ent = arch_get_frame_entity(env->arch_env, node);
-			check_entity(env, node, ent);
+			ir_entity *ent = arch_get_frame_entity(env->arch_env, node);
+			be_check_entity(env, node, ent);
 		}
 
 		if(spill == NULL) {
@@ -596,33 +724,85 @@ typedef struct _be_verify_register_allocation_env_t {
 	int problem_found;
 } be_verify_register_allocation_env_t;
 
-static void check_register_allocation(be_verify_register_allocation_env_t *env,
-                                      const arch_register_class_t *regclass, pset *nodes) {
-	const arch_env_t *arch_env = env->arch_env;
-	ir_node *node;
+static void check_register_constraints(ir_node *node, be_verify_register_allocation_env_t *env) {
+	const arch_env_t      *arch_env = env->arch_env;
 	const arch_register_t *reg;
-	int fail = 0;
+	int                   i, arity;
 
-	bitset_t *registers = bitset_alloca(arch_register_class_n_regs(regclass));
+	/* verify output register */
+	if (arch_get_irn_reg_class(arch_env, node, -1) != NULL) {
+		reg = arch_get_irn_register(arch_env, node);
+		if (reg == NULL) {
+			ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have a register assigned\n",
+					node, get_nodes_block(node), get_irg_dump_name(env->irg));
+			env->problem_found = 1;
+		}
+		else if (! arch_register_type_is(reg, joker) && !arch_reg_is_allocatable(arch_env, node, -1, reg)) {
+			ir_fprintf(stderr, "Verify warning: Register %s assigned as output of %+F not allowed (register constraint) in block %+F(%s)\n",
+					reg->name, node, get_nodes_block(node), get_irg_dump_name(env->irg));
+			env->problem_found = 1;
+		}
+	}
 
-	foreach_pset(nodes, node) {
-		if(arch_get_irn_reg_class(arch_env, node, -1) != regclass)
+	/* verify input register */
+	arity = get_irn_arity(node);
+	for (i = 0; i < arity; ++i) {
+		ir_node *pred = get_irn_n(node, i);
+
+		if (is_Unknown(pred))
 			continue;
 
-		reg = arch_get_irn_register(arch_env, node);
-		if(reg == NULL) {
+		if (is_Bad(pred)) {
+			ir_fprintf(stderr, "Verify warning: %+F in block %+F(%s) has Bad as input %d\n",
+				node, get_nodes_block(node), get_irg_dump_name(env->irg), i);
+			env->problem_found = 1;
+			continue;
+		}
+
+		if (arch_get_irn_reg_class(arch_env, node, i) == NULL)
+			continue;
+
+		reg = arch_get_irn_register(arch_env, pred);
+		if (reg == NULL) {
 			ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have a register assigned\n",
-			           node, get_nodes_block(node), get_irg_dump_name(env->irg));
+			           pred, get_nodes_block(pred), get_irg_dump_name(env->irg));
 			env->problem_found = 1;
 			continue;
 		}
-		if(bitset_is_set(registers, reg->index)) {
+		else if (! arch_register_type_is(reg, joker) && ! arch_reg_is_allocatable(arch_env, node, i, reg)) {
+			ir_fprintf(stderr, "Verify warning: Register %s as input %d of %+F not allowed (register constraint) in block %+F(%s)\n",
+			           reg->name, i, node, get_nodes_block(node), get_irg_dump_name(env->irg));
+			env->problem_found = 1;
+		}
+	}
+}
+
+static void check_register_allocation(be_verify_register_allocation_env_t *env,
+                                      const arch_register_class_t *regclass, pset *nodes) {
+	const arch_env_t      *arch_env  = env->arch_env;
+	const arch_register_t *reg       = NULL;
+	int                   fail       = 0;
+	bitset_t              *registers = bitset_alloca(arch_register_class_n_regs(regclass));
+	ir_node               *node;
+
+	foreach_pset(nodes, node) {
+		if (arch_get_irn_reg_class(arch_env, node, -1) != regclass)
+			continue;
+
+		reg = arch_get_irn_register(arch_env, node);
+
+		/* this problem is already reported in 'check_register_constraints' */
+		if (! reg)
+			continue;
+
+		if (bitset_is_set(registers, reg->index)) {
 			pset_break(nodes);
 			fail = 1;
 			break;
 		}
 		bitset_set(registers, reg->index);
 	}
+
 	if (fail) {
 		ir_fprintf(stderr, "Verify warning: Register %s assigned more than once in block %+F(%s)\n",
 			       reg->name, get_nodes_block(node), get_irg_dump_name(env->irg));
@@ -657,6 +837,7 @@ static void verify_block_register_allocation(ir_node *block, void *data) {
 
 			be_liveness_transfer(env->arch_env, regclass, node, live_nodes);
 			check_register_allocation(env, regclass, live_nodes);
+			check_register_constraints(node, env);
 		}
 
 		del_pset(live_nodes);
@@ -671,9 +852,65 @@ int be_verify_register_allocation(const arch_env_t *arch_env, ir_graph *irg) {
 	env.lv = be_liveness(irg);
 	env.problem_found = 0;
 
+	be_liveness_assure_sets(env.lv);
 	irg_block_walk_graph(irg, verify_block_register_allocation, NULL, &env);
 
 	be_liveness_free(env.lv);
 
 	return !env.problem_found;
 }
+
+
+
+//---------------------------------------------------------------------------
+
+
+
+typedef struct _verify_out_dead_nodes_env {
+	ir_graph *irg;
+	bitset_t *reachable;
+	int problem_found;
+} verify_out_dead_nodes_env;
+
+static void check_out_edges(ir_node *node, verify_out_dead_nodes_env *env) {
+	ir_graph *irg = env->irg;
+	const ir_edge_t* edge;
+
+	if(irn_visited(node))
+		return;
+	mark_irn_visited(node);
+
+	foreach_out_edge(node, edge) {
+		ir_node* src = get_edge_src_irn(edge);
+
+		if(!bitset_is_set(env->reachable, get_irn_idx(src)) && !is_Block(node)) {
+			ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) only reachable through out edges from %+F\n",
+			           src, get_nodes_block(src), get_irg_dump_name(irg), node);
+			env->problem_found = 1;
+			continue;
+		}
+
+		check_out_edges(src, env);
+	}
+}
+
+static void set_reachable(ir_node *node, void* data)
+{
+	bitset_t* reachable = data;
+	bitset_set(reachable, get_irn_idx(node));
+}
+
+int be_verify_out_edges(ir_graph *irg) {
+	verify_out_dead_nodes_env env;
+
+	env.irg           = irg;
+	env.reachable     = bitset_alloca(get_irg_last_idx(irg));
+	env.problem_found = edges_verify(irg);
+
+	irg_walk_in_or_dep_graph(irg, set_reachable, NULL, env.reachable);
+	irg_walk_anchors(irg, set_reachable, NULL, env.reachable);
+	inc_irg_visited(irg);
+	check_out_edges(get_irg_start(irg), &env);
+
+	return ! env.problem_found;
+}