From ed1add2d5c8f8256a31b3347b9acaaf7f3ea644a Mon Sep 17 00:00:00 2001
From: Matthias Braun <matze@braunis.de>
Date: Thu, 4 Oct 2007 19:18:05 +0000
Subject: [PATCH] - introduce an "end-block" to the absgraph, so the
 irg_end_block is known in a   dfs even if the program contains just an
 endless loop

[r16090]
---
 include/libfirm/absgraph.h |  1 +
 ir/ana/absgraph.c          | 19 ++++++++++++++++---
 ir/ana/dfs.c               | 26 ++++++++++++++++++--------
 ir/ana/irlivechk.c         |  7 +++++++
 4 files changed, 42 insertions(+), 11 deletions(-)

diff --git a/include/libfirm/absgraph.h b/include/libfirm/absgraph.h
index 9b6a7d2e5..613cb9c7d 100644
--- a/include/libfirm/absgraph.h
+++ b/include/libfirm/absgraph.h
@@ -38,6 +38,7 @@
 typedef struct _absgraph_t {
 	void *(*get_root)(void *self);
 	void (*grow_succs)(void *self, void *node, struct obstack *obst);
+	void *(*get_end)(void *self);
 } absgraph_t;
 
 extern const absgraph_t absgraph_irg_cfg_succ;
diff --git a/ir/ana/absgraph.c b/ir/ana/absgraph.c
index 1d483e24f..bc2c97fd7 100644
--- a/ir/ana/absgraph.c
+++ b/ir/ana/absgraph.c
@@ -41,6 +41,12 @@ static void *irg_cfg_succ_get_root(void *self)
 	return get_irg_start_block(irg);
 }
 
+static void *irg_cfg_succ_get_end(void *self)
+{
+	ir_graph *irg = self;
+	return get_irg_end_block(irg);
+}
+
 static void irg_cfg_succ_grow_succs(void *self, void *node, struct obstack *obst)
 {
 	ir_node *bl = node;
@@ -54,12 +60,18 @@ static void irg_cfg_succ_grow_succs(void *self, void *node, struct obstack *obst
 
 const absgraph_t absgraph_irg_cfg_succ = {
 	irg_cfg_succ_get_root,
-	irg_cfg_succ_grow_succs
+	irg_cfg_succ_grow_succs,
+	irg_cfg_succ_get_end
 };
 
 static void *irg_cfg_pred_get_root(void *self)
 {
-	return get_irg_end_block(self);
+	return get_irg_end_block((ir_graph*) self);
+}
+
+static void *irg_cfg_pred_get_end(void *self)
+{
+	return get_irg_start_block((ir_graph*) self);
 }
 
 static void irg_cfg_pred_grow_succs(void *self, void *node, struct obstack *obst)
@@ -74,5 +86,6 @@ static void irg_cfg_pred_grow_succs(void *self, void *node, struct obstack *obst
 
 const absgraph_t absgraph_irg_cfg_pred = {
 	irg_cfg_pred_get_root,
-	irg_cfg_pred_grow_succs
+	irg_cfg_pred_grow_succs,
+	irg_cfg_pred_get_end
 };
diff --git a/ir/ana/dfs.c b/ir/ana/dfs.c
index a85064aeb..ca080d475 100644
--- a/ir/ana/dfs.c
+++ b/ir/ana/dfs.c
@@ -40,13 +40,6 @@
 #include "statev.h"
 #include "dfs_t.h"
 
-static const char *edge_names[] = {
-	"anc",
-	"fwd",
-	"cross",
-	"back"
-};
-
 static int cmp_edge(const void *a, const void *b, size_t sz)
 {
 	const dfs_edge_t *p = a;
@@ -182,11 +175,28 @@ dfs_t *dfs_new(const absgraph_t *graph_impl, void *graph_self)
 	obstack_init(&res->obst);
 
 	dfs_perform(res, graph_impl->get_root(graph_self), NULL, 0);
+
+	/* make sure the end node (which might not be accessible) has a number */
+	node = get_node(res, graph_impl->get_end(graph_self));
+	if (!node->visited) {
+		node->visited     = 1;
+		node->node        = graph_impl->get_end(graph_self);
+		node->ancestor    = NULL;
+		node->pre_num     = res->pre_num++;
+		node->post_num    = res->post_num++;
+		node->max_pre_num = node->pre_num;
+		node->level       = 0;
+	}
+
 	classify_edges(res);
 
+	assert(res->pre_num == res->post_num);
 	res->pre_order = xmalloc(res->pre_num * sizeof(res->pre_order));
-	res->post_order = xmalloc(res->pre_num * sizeof(res->post_order));
+	res->post_order = xmalloc(res->post_num * sizeof(res->post_order));
 	foreach_set (res->nodes, node) {
+		assert(node->pre_num < res->pre_num);
+		assert(node->post_num < res->post_num);
+
 		res->pre_order[node->pre_num] = node;
 		res->post_order[node->post_num] = node;
 	}
diff --git a/ir/ana/irlivechk.c b/ir/ana/irlivechk.c
index 4aa00d86c..2d6e91a71 100644
--- a/ir/ana/irlivechk.c
+++ b/ir/ana/irlivechk.c
@@ -247,6 +247,10 @@ lv_chk_t *lv_chk_new(ir_graph *irg, const dfs_t *dfs)
 	struct obstack *obst;
 	int i;
 
+	edges_deactivate(irg);
+	edges_activate(irg);
+	compute_doms(irg);
+
 	stat_ev_tim_push();
 	phase_init(&res->ph, "liveness check", irg, PHASE_DEFAULT_GROWTH, init_block_data, NULL);
 	obst = phase_obst(&res->ph);
@@ -258,6 +262,7 @@ lv_chk_t *lv_chk_new(ir_graph *irg, const dfs_t *dfs)
 	res->back_edge_src = bitset_obstack_alloc(obst, res->n_blocks);
 	res->back_edge_tgt = bitset_obstack_alloc(obst, res->n_blocks);
 	res->map           = obstack_alloc(obst, res->n_blocks * sizeof(res->map[0]));
+	memset(res->map, 0, res->n_blocks * sizeof(res->map[0]));
 
 #if 0
 	{
@@ -276,6 +281,8 @@ lv_chk_t *lv_chk_new(ir_graph *irg, const dfs_t *dfs)
 	for (i = res->n_blocks - 1; i >= 0; --i) {
 		ir_node *irn  = (ir_node *) dfs_get_pre_num_node(res->dfs, i);
 		bl_info_t *bi = phase_get_or_set_irn_data(&res->ph, irn);
+		assert(bi->id < res->n_blocks);
+		assert(res->map[bi->id] == NULL);
 		res->map[bi->id] = bi;
 	}
 
-- 
2.20.1