X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbelive.c;h=392d350d4417bbccfe7149e118bd027ba5f6b921;hb=1b4cac3471b02b63e9656cd8c876f067766fe482;hp=a3d268fac80bbedc23422c1e6cc229c50c130abd;hpb=81143885a3389e3d26fc5a91e1777ab8aac7b547;p=libfirm

diff --git a/ir/be/belive.c b/ir/be/belive.c
index a3d268fac..392d350d4 100644
--- a/ir/be/belive.c
+++ b/ir/be/belive.c
@@ -204,41 +204,10 @@ static int be_lv_remove(be_lv_t *li, const ir_node *bl,
 	return 0;
 }
 
-/**
- * Mark a node as live-in in a block.
- */
-static inline void mark_live_in(be_lv_t *lv, ir_node *block, ir_node *irn)
-{
-	be_lv_info_node_t *n = be_lv_get_or_set(lv, block, irn);
-	DBG((dbg, LEVEL_2, "marking %+F live in at %+F\n", irn, block));
-	n->flags |= be_lv_state_in;
-}
-
-/**
- * Mark a node as live-out in a block.
- */
-static inline void mark_live_out(be_lv_t *lv, ir_node *block, ir_node *irn)
-{
-	be_lv_info_node_t *n = be_lv_get_or_set(lv, block, irn);
-	DBG((dbg, LEVEL_2, "marking %+F live out at %+F\n", irn, block));
-	n->flags |= be_lv_state_out | be_lv_state_end;
-}
-
-/**
- * Mark a node as live-end in a block.
- */
-static inline void mark_live_end(be_lv_t *lv, ir_node *block, ir_node *irn)
-{
-	be_lv_info_node_t *n = be_lv_get_or_set(lv, block, irn);
-	DBG((dbg, LEVEL_2, "marking %+F live end at %+F\n", irn, block));
-	n->flags |= be_lv_state_end;
-}
-
 static struct {
 	be_lv_t  *lv;         /**< The liveness object. */
 	ir_node  *def;        /**< The node (value). */
 	ir_node  *def_block;  /**< The block of def. */
-	bitset_t *visited;    /**< A set were all visited blocks are recorded. */
 } re;
 
 /**
@@ -246,35 +215,32 @@ static struct {
  * transitively, i.e. if the block is not the block of the value's
  * definition, all predecessors are also marked live.
  * @param block The block to mark the value live out of.
- * @param is_true_out Is the node real out there or only live at the end
- * of the block.
+ * @param state The liveness bits to set, either end or end+out.
  */
-static void live_end_at_block(ir_node *block, int is_true_out)
+static void live_end_at_block(ir_node *const block, be_lv_state_t const state)
 {
-	be_lv_t *lv  = re.lv;
-	ir_node *def = re.def;
-	bitset_t *visited;
+	be_lv_info_node_t *const n      = be_lv_get_or_set(re.lv, block, re.def);
+	be_lv_state_t      const before = n->flags;
 
-	mark_live_end(lv, block, def);
-	if (is_true_out)
-		mark_live_out(lv, block, def);
+	assert(state == be_lv_state_end || state == (be_lv_state_end | be_lv_state_out));
+	DBG((dbg, LEVEL_2, "marking %+F live %s at %+F\n", re.def, state & be_lv_state_out ? "end+out" : "end", block));
+	n->flags |= state;
 
-	visited = re.visited;
-	if (!bitset_is_set(visited, get_irn_idx(block))) {
-		bitset_set(visited, get_irn_idx(block));
+	/* There is no need to recurse further, if we where here before (i.e., any
+	 * live state bits were set before). */
+	if (before != be_lv_state_none)
+		return;
 
-		/*
-		 * If this block is not the definition block, we have to go up
-		 * further.
-		 */
-		if (re.def_block != block) {
-			int i;
+	/* Stop going up further, if this is the block of the definition. */
+	if (re.def_block == block)
+		return;
 
-			mark_live_in(lv, block, def);
+	DBG((dbg, LEVEL_2, "marking %+F live in at %+F\n", re.def, block));
+	n->flags |= be_lv_state_in;
 
-			for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i)
-				live_end_at_block(get_Block_cfgpred_block(block, i), 1);
-		}
+	for (int i = get_Block_n_cfgpreds(block); i-- != 0;) {
+		ir_node *const pred_block = get_Block_cfgpred_block(block, i);
+		live_end_at_block(pred_block, be_lv_state_end | be_lv_state_out);
 	}
 }
 
@@ -291,10 +257,7 @@ typedef struct lv_remove_walker_t {
  */
 static void liveness_for_node(ir_node *irn)
 {
-	ir_node *def_block;
-
-	bitset_clear_all(re.visited);
-	def_block = get_nodes_block(irn);
+	ir_node *const def_block = get_nodes_block(irn);
 
 	re.def       = irn;
 	re.def_block = def_block;
@@ -324,7 +287,7 @@ static void liveness_for_node(ir_node *irn)
 		 */
 		if (is_Phi(use)) {
 			ir_node *pred_block = get_Block_cfgpred_block(use_block, edge->pos);
-			live_end_at_block(pred_block, 0);
+			live_end_at_block(pred_block, be_lv_state_end);
 		}
 
 		/*
@@ -334,11 +297,13 @@ static void liveness_for_node(ir_node *irn)
 		else if (def_block != use_block) {
 			int i;
 
-			mark_live_in(re.lv, use_block, irn);
+			be_lv_info_node_t *const n = be_lv_get_or_set(re.lv, use_block, irn);
+			DBG((dbg, LEVEL_2, "marking %+F live in at %+F\n", irn, use_block));
+			n->flags |= be_lv_state_in;
 
 			for (i = get_Block_n_cfgpreds(use_block) - 1; i >= 0; --i) {
 				ir_node *pred_block = get_Block_cfgpred_block(use_block, i);
-				live_end_at_block(pred_block, 1);
+				live_end_at_block(pred_block, be_lv_state_end | be_lv_state_out);
 			}
 		}
 	}
@@ -363,7 +328,6 @@ static void collect_liveness_nodes(ir_node *irn, void *data)
 
 void be_liveness_compute_sets(be_lv_t *lv)
 {
-	ir_node **nodes;
 	int       i;
 	int       n;
 
@@ -375,16 +339,14 @@ void be_liveness_compute_sets(be_lv_t *lv)
 	obstack_init(&lv->obst);
 
 	n = get_irg_last_idx(lv->irg);
-	nodes = NEW_ARR_F(ir_node *, n);
-	memset(nodes, 0, sizeof(nodes[0]) * n);
+	ir_node **const nodes = NEW_ARR_FZ(ir_node*, n);
 
 	/* inserting the variables sorted by their ID is probably
 	 * more efficient since the binary sorted set insertion
 	 * will not need to move around the data. */
 	irg_walk_graph(lv->irg, NULL, collect_liveness_nodes, nodes);
 
-	re.lv      = lv;
-	re.visited = bitset_malloc(n);
+	re.lv = lv;
 
 	for (i = 0; i < n; ++i) {
 		if (nodes[i] != NULL)
@@ -392,7 +354,6 @@ void be_liveness_compute_sets(be_lv_t *lv)
 	}
 
 	DEL_ARR_F(nodes);
-	free(re.visited);
 
 	be_timer_pop(T_LIVE);
 
@@ -462,10 +423,8 @@ void be_liveness_introduce(be_lv_t *lv, ir_node *irn)
 {
 	/* Don't compute liveness information for non-data nodes. */
 	if (lv->sets_valid && is_liveness_node(irn)) {
-		re.lv      = lv;
-		re.visited = bitset_malloc(get_irg_last_idx(lv->irg));
+		re.lv = lv;
 		liveness_for_node(irn);
-		bitset_free(re.visited);
 	}
 }