X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbeverify.c;h=7b3f5d4f093b80ec23cfad58f6402f1eec94a847;hb=f73b8014037f87fca038a96e04a9a8cc5354079c;hp=97a3322a3d67c8794df101df3af35df5e10b0204;hpb=48f893878b07f6e334389ff52abda5cc2adbf179;p=libfirm

diff --git a/ir/be/beverify.c b/ir/be/beverify.c
index 97a3322a3..7b3f5d4f0 100644
--- a/ir/be/beverify.c
+++ b/ir/be/beverify.c
@@ -9,17 +9,24 @@
 #include "config.h"
 #endif
 
-#include "beverify.h"
-#include "belive.h"
-#include "besched_t.h"
+#include "bitset.h"
+#include "set.h"
+#include "array.h"
 
 #include "irnode.h"
 #include "irgraph.h"
 #include "irgwalk.h"
 #include "irprintf.h"
 #include "irdump_t.h"
+#include "iredges.h"
+
+#include "beverify.h"
+#include "belive.h"
+#include "besched_t.h"
 #include "benode_t.h"
 
+static int my_values_interfere(const ir_node *a, const ir_node *b);
+
 typedef struct be_verify_register_pressure_env_t_ {
 	ir_graph                    *irg;                 /**< the irg to verify */
 	 be_lv_t                    *lv;                  /**< Liveness information. */
@@ -32,8 +39,7 @@ typedef struct be_verify_register_pressure_env_t_ {
 /**
  * Print all nodes of a pset into a file.
  */
-static void print_living_values(FILE *F, pset *live_nodes)
-{
+static void print_living_values(FILE *F, pset *live_nodes) {
 	ir_node *node;
 
 	ir_fprintf(F, "\t");
@@ -46,8 +52,7 @@ static void print_living_values(FILE *F, pset *live_nodes)
 /**
  * Check if number of live nodes never exceeds the number of available registers.
  */
-static void verify_liveness_walker(ir_node *block, void *data)
-{
+static void verify_liveness_walker(ir_node *block, void *data) {
 	be_verify_register_pressure_env_t *env = (be_verify_register_pressure_env_t *)data;
 	pset    *live_nodes = pset_new_ptr_default();
 	ir_node *irn;
@@ -85,15 +90,14 @@ 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;
 
 	irg_block_walk_graph(irg, verify_liveness_walker, NULL, &env);
@@ -110,15 +114,13 @@ typedef struct be_verify_schedule_env_t_ {
 /**
  * Simple schedule checker.
  */
-static void verify_schedule_walker(ir_node *block, void *data)
-{
+static void verify_schedule_walker(ir_node *block, void *data) {
 	be_verify_schedule_env_t *env = (be_verify_schedule_env_t*) data;
 	ir_node *node;
 	int non_phi_found  = 0;
 	int cfchange_found = 0;
 	// TODO ask arch about delay branches
 	int delay_branches = 0;
-	pset *uses = pset_new_ptr_default();
 
 	/*
 	 * Tests for the following things:
@@ -164,27 +166,81 @@ static void verify_schedule_walker(ir_node *block, void *data)
 		}
 
 		// 3. Check for uses
-		if(pset_find_ptr(uses, node)) {
-			ir_fprintf(stderr, "Verify Warning: Value %+F used before it was defined in block %+F (%s)\n",
-				node, block, get_irg_dump_name(env->irg));
-			env->problem_found = 1;
-		}
 		if(!is_Phi(node)) {
+			int nodetime = sched_get_time_step(node);
 			for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
-				pset_insert_ptr(uses, get_irn_n(node, i));
+				ir_node *arg = get_irn_n(node, i);
+				if(get_nodes_block(arg) != block
+				   || !sched_is_scheduled(arg))
+					continue;
+
+				if(sched_get_time_step(arg) >= nodetime) {
+					ir_fprintf(stderr, "Verify Warning: Value %+F used by %+F before it was defined in block %+F (%s)\n",
+					           arg, node, block, get_irg_dump_name(env->irg));
+					env->problem_found = 1;
+				}
 			}
 		}
+
+		// 4. check for dead nodes
+		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;
+		}
 	}
-	del_pset(uses);
 
 	/* check that all delay branches are filled (at least with NOPs) */
 	if (cfchange_found && delay_branches != 0) {
-		ir_fprintf(stderr, "Not all delay slots filled after jump (%d/%d) in block %+F (%s)\n",
+		ir_fprintf(stderr, "Verify warning: Not all delay slots filled after jump (%d/%d) in block %+F (%s)\n",
 			block, get_irg_dump_name(env->irg));
 		env->problem_found = 1;
 	}
 }
 
+static int should_be_scheduled(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) || is_Pin(node))
+			return 0;
+	}
+	if(is_Proj(node) && get_irn_mode(node) == mode_X)
+		return 0;
+	if(be_is_Keep(node) && get_irn_opcode(get_nodes_block(node)) == iro_Bad)
+		return 0;
+
+	switch(get_irn_opcode(node)) {
+	case iro_End:
+	case iro_NoMem:
+	case iro_Bad:
+	case iro_Unknown:
+		return 0;
+	default:
+		break;
+	}
+
+	return 1;
+}
+
+static void check_schedule(ir_node *node, void *data) {
+	be_verify_schedule_env_t *env = data;
+	int should_be;
+
+	should_be = should_be_scheduled(node);
+	if(should_be == -1)
+		return;
+
+	if(should_be ? !sched_is_scheduled(node) : sched_is_scheduled(node)) {
+		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;
+	}
+}
+
 /**
  * Start a walk over the irg and check schedule.
  */
@@ -196,6 +252,538 @@ int be_verify_schedule(ir_graph *irg)
 	env.irg           = irg;
 
 	irg_block_walk_graph(irg, verify_schedule_walker, NULL, &env);
+	// check if all nodes are scheduled
+	irg_walk_graph(irg, check_schedule, NULL, &env);
 
 	return ! env.problem_found;
 }
+
+
+
+//---------------------------------------------------------------------------
+
+
+
+typedef struct _spill_t {
+	ir_node *spill;
+	ir_entity *ent;
+} spill_t;
+
+typedef struct {
+	const arch_env_t *arch_env;
+	ir_graph *irg;
+	set *spills;
+	ir_node **reloads;
+	int problem_found;
+} be_verify_spillslots_env_t;
+
+static int cmp_spill(const void* d1, const void* d2, size_t size) {
+	const spill_t* s1 = d1;
+	const spill_t* s2 = d2;
+	return s1->spill != s2->spill;
+}
+
+static spill_t *find_spill(be_verify_spillslots_env_t *env, ir_node *node) {
+	spill_t spill;
+
+	spill.spill = 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, ir_entity *ent) {
+	spill_t spill, *res;
+	int hash = HASH_PTR(node);
+
+	spill.spill = node;
+	res = set_find(env->spills, &spill, sizeof(spill), hash);
+
+	if(res == NULL) {
+		spill.ent = ent;
+		res = set_insert(env->spills, &spill, sizeof(spill), hash);
+	}
+
+	return res;
+}
+
+static ir_node *get_memory_edge(const ir_node *node) {
+	int i, arity;
+	ir_node *result = NULL;
+
+	arity = get_irn_arity(node);
+	for(i = arity - 1; i >= 0; --i) {
+		ir_node *arg = get_irn_n(node, i);
+		if(get_irn_mode(arg) == mode_M) {
+			assert(result == NULL);
+			result = arg;
+		}
+	}
+
+	return result;
+}
+
+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, 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, ir_entity* ent) {
+	ir_entity *spillent = arch_get_frame_entity(env->arch_env, node);
+	check_entity(env, node, spillent);
+	get_spill(env, node, ent);
+
+	if(spillent != ent) {
+		ir_fprintf(stderr, "Verify warning: Spill %+F has different entity than reload %+F in block %+F(%s)\n",
+			node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
+		env->problem_found = 1;
+	}
+}
+
+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;
+	ir_entity *spillent;
+
+	assert(is_Proj(node));
+
+	memperm = get_Proj_pred(node);
+	out = get_Proj_proj(node);
+
+	spillent = be_get_MemPerm_out_entity(memperm, out);
+	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));
+		env->problem_found = 1;
+	}
+
+	spill.spill = node;
+	res = set_find(env->spills, &spill, sizeof(spill), hash);
+	if(res != NULL) {
+		return;
+	}
+
+	spill.ent = spillent;
+	res = set_insert(env->spills, &spill, sizeof(spill), hash);
+
+	for(i = 0, arity = be_get_MemPerm_entity_arity(memperm); i < arity; ++i) {
+		ir_node* arg = get_irn_n(memperm, i + 1);
+		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, ir_entity *ent) {
+	int i, arity;
+	spill_t spill, *res;
+	int hash = HASH_PTR(node);
+
+	assert(is_Phi(node));
+
+	spill.spill = node;
+	res = set_find(env->spills, &spill, sizeof(spill), hash);
+	if(res != NULL) {
+		return;
+	}
+
+	spill.ent = ent;
+	res = set_insert(env->spills, &spill, sizeof(spill), hash);
+
+	// is 1 of the arguments a spill?
+	for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
+		ir_node* arg = get_irn_n(node, i);
+		collect(env, arg, reload, 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)) {
+		collect_memperm(env, node, reload, ent);
+	} else if(is_Phi(node) && get_irn_mode(node) == mode_M) {
+		collect_memphi(env, node, reload, ent);
+	} else {
+		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;
+	}
+}
+
+/**
+ * This walker function searches for reloads and collects all the spills
+ * and memphis attached to them.
+ */
+static void collect_spills_walker(ir_node *node, void *data) {
+	be_verify_spillslots_env_t *env = data;
+	const arch_env_t *arch_env = env->arch_env;
+
+	// @@@ ia32_classify returns classification of Proj_pred :-/
+	if(is_Proj(node))
+		return;
+
+	if(arch_irn_class_is(arch_env, node, reload)) {
+		ir_node *spill = get_memory_edge(node);
+		ir_entity *ent;
+
+		if(spill == NULL) {
+			ir_fprintf(stderr, "Verify warning: No spill attached to reload %+F in block %+F(%s)\n",
+			           node, get_nodes_block(node), get_irg_dump_name(env->irg));
+			env->problem_found = 1;
+			return;
+		}
+		ent = arch_get_frame_entity(env->arch_env, node);
+		check_entity(env, node, ent);
+
+		collect(env, spill, node, ent);
+		ARR_APP1(ir_node*, env->reloads, node);
+	}
+}
+
+static void check_spillslot_interference(be_verify_spillslots_env_t *env) {
+	int spillcount = set_count(env->spills);
+	spill_t **spills = alloca(spillcount * sizeof(spills[0]));
+	spill_t *spill;
+	int i;
+
+	for(spill = set_first(env->spills), i = 0; spill != NULL; spill = set_next(env->spills), ++i) {
+		spills[i] = spill;
+	}
+
+	for(i = 0; i < spillcount; ++i) {
+		spill_t *sp1 = spills[i];
+		int i2;
+
+		for(i2 = i+1; i2 < spillcount; ++i2) {
+			spill_t *sp2 = spills[i2];
+
+			if(sp1->ent != sp2->ent)
+				continue;
+
+			if(my_values_interfere(sp1->spill, sp2->spill)) {
+				ir_fprintf(stderr, "Verify warning: Spillslots for %+F in block %+F(%s) and %+F in block %+F(%s) interfere\n",
+					sp1->spill, get_nodes_block(sp1->spill), get_irg_dump_name(env->irg),
+					sp2->spill, get_nodes_block(sp2->spill), get_irg_dump_name(env->irg));
+				env->problem_found = 1;
+				my_values_interfere(sp1->spill, sp2->spill);
+			}
+		}
+	}
+}
+
+static void check_lonely_spills(ir_node *node, void *data) {
+	be_verify_spillslots_env_t *env = 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)) {
+			ir_entity *ent = arch_get_frame_entity(env->arch_env, node);
+			check_entity(env, node, ent);
+		}
+
+		if(spill == NULL) {
+			ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) not connected to a reaload\n",
+			           node, get_nodes_block(node), get_irg_dump_name(env->irg));
+		}
+	}
+}
+
+int be_verify_spillslots(const arch_env_t *arch_env, ir_graph *irg)
+{
+	be_verify_spillslots_env_t env;
+
+	env.arch_env = arch_env;
+	env.irg = irg;
+	env.spills = new_set(cmp_spill, 10);
+	env.reloads = NEW_ARR_F(ir_node*, 0);
+	env.problem_found = 0;
+
+	irg_walk_graph(irg, collect_spills_walker, NULL, &env);
+	irg_walk_graph(irg, check_lonely_spills, NULL, &env);
+
+	check_spillslot_interference(&env);
+
+	DEL_ARR_F(env.reloads);
+	del_set(env.spills);
+
+	return ! env.problem_found;
+}
+
+
+
+//---------------------------------------------------------------------------
+
+
+
+/**
+ * Check, if two values interfere.
+ * @param a The first value.
+ * @param b The second value.
+ * @return 1, if a and b interfere, 0 if not.
+ */
+static int my_values_interfere(const ir_node *a, const ir_node *b) {
+	const ir_edge_t *edge;
+	ir_node *bb;
+	int a2b = value_dominates(a, b);
+	int b2a = value_dominates(b, a);
+
+	/* If there is no dominance relation, they do not interfere. */
+	if(!a2b && !b2a)
+		return 0;
+
+	/*
+	 * Adjust a and b so, that a dominates b if
+	 * a dominates b or vice versa.
+	 */
+	if(b2a) {
+		const ir_node *t = a;
+		a = b;
+		b = t;
+	}
+
+	bb = get_nodes_block(b);
+
+	/*
+	 * Look at all usages of a.
+	 * If there's one usage of a in the block of b, then
+	 * we check, if this use is dominated by b, if that's true
+	 * a and b interfere. Note that b must strictly dominate the user,
+	 * since if b is the last user of in the block, b and a do not
+	 * interfere.
+	 * Uses of a not in b's block can be disobeyed, because the
+	 * check for a being live at the end of b's block is already
+	 * performed.
+	 */
+	foreach_out_edge(a, edge) {
+		const ir_node *user = get_edge_src_irn(edge);
+		if(b == user)
+			continue;
+
+		if(get_irn_opcode(user) == iro_End)
+			continue;
+
+		// in case of phi arguments we compare with the block the value comes from
+		if(is_Phi(user)) {
+			ir_node *phiblock = get_nodes_block(user);
+			if(phiblock == bb)
+				continue;
+			user = get_irn_n(phiblock, get_edge_src_pos(edge));
+		}
+
+		if(value_dominates(b, user))
+			return 1;
+	}
+
+	return 0;
+}
+
+
+
+//---------------------------------------------------------------------------
+
+
+
+typedef struct _be_verify_register_allocation_env_t {
+	const arch_env_t *arch_env;
+	ir_graph *irg;
+	be_lv_t *lv;
+	int problem_found;
+} be_verify_register_allocation_env_t;
+
+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                   i, arity;
+
+	/* 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;
+		}
+	}
+
+	/* verify input register */
+	arity = get_irn_arity(node);
+	for (i = 0; i < arity; ++i) {
+		ir_node *pred = get_irn_n(node, i);
+
+		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",
+			           pred, get_nodes_block(pred), get_irg_dump_name(env->irg));
+			env->problem_found = 1;
+			continue;
+		}
+		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));
+		env->problem_found = 1;
+
+		foreach_pset(nodes, node) {
+			if (arch_get_irn_register(arch_env, node) == reg) {
+				ir_fprintf(stderr, "  at node %+F\n", node);
+			}
+		}
+	}
+}
+
+static void verify_block_register_allocation(ir_node *block, void *data) {
+	be_verify_register_allocation_env_t *env = data;
+	const arch_env_t *arch_env = env->arch_env;
+	const arch_isa_t *isa = arch_env->isa;
+	int i, nregclasses;
+
+	nregclasses = arch_isa_get_n_reg_class(isa);
+	for (i = 0; i < nregclasses; ++i) {
+		const arch_register_class_t *regclass = arch_isa_get_reg_class(isa, i);
+		ir_node *node;
+		pset *live_nodes = pset_new_ptr_default();
+
+		be_liveness_end_of_block(env->lv, env->arch_env, regclass, block, live_nodes);
+		check_register_allocation(env, regclass, live_nodes);
+
+		sched_foreach_reverse(block, node) {
+			if (is_Phi(node))
+				break;
+
+			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);
+	}
+}
+
+int be_verify_register_allocation(const arch_env_t *arch_env, ir_graph *irg) {
+	be_verify_register_allocation_env_t env;
+
+	env.arch_env = arch_env;
+	env.irg = irg;
+	env.lv = be_liveness(irg);
+	env.problem_found = 0;
+
+	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))) {
+			if(src != get_irg_globals(irg)
+					&& src != get_irg_tls(irg)) {
+				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;
+		}
+
+		if(!is_Block(src)) {
+			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 = 0;
+
+	irg_walk_graph(irg, set_reachable, NULL, env.reachable);
+	inc_irg_visited(irg);
+	check_out_edges(get_irg_start(irg), &env);
+
+	return !env.problem_found;
+}