X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=mono%2Fmini%2Fseq-points.c;h=8ff2e1e3ec6ca95145828a077e03d8a48cb8d709;hb=e0f96a41c6b60b8c4dc5389e4cf9b906e3b26f75;hp=ac22ca41f070d0201b7c4b55371cc597b1e97a51;hpb=ccdf8c3274d1793ffeddedfd784d49707feea62a;p=mono.git

diff --git a/mono/mini/seq-points.c b/mono/mini/seq-points.c
index ac22ca41f07..8ff2e1e3ec6 100644
--- a/mono/mini/seq-points.c
+++ b/mono/mini/seq-points.c
@@ -5,37 +5,95 @@
  *   Marcos Henrich (marcos.henrich@xamarin.com)
  *
  * Copyright 2014 Xamarin, Inc (http://www.xamarin.com)
+ * Licensed under the MIT license. See LICENSE file in the project root for full license information.
  */
 
 #include "mini.h"
 #include "seq-points.h"
 
 static void
-collect_pred_seq_points (MonoBasicBlock *bb, MonoInst *ins, GSList **next, int depth)
+insert_pred_seq_point (MonoInst *last_seq_ins, MonoInst *ins, GSList **next)
 {
-	int i;
-	MonoBasicBlock *in_bb;
 	GSList *l;
+	int src_index = last_seq_ins->backend.size;
+	int dst_index = ins->backend.size;
+
+	/* bb->in_bb might contain duplicates */
+	for (l = next [src_index]; l; l = l->next)
+		if (GPOINTER_TO_UINT (l->data) == dst_index)
+			break;
+	if (!l)
+		next [src_index] = g_slist_append (next [src_index], GUINT_TO_POINTER (dst_index));
+}
+
+static void
+recursively_make_pred_seq_points (MonoCompile *cfg, MonoBasicBlock *bb)
+{
+	const gpointer MONO_SEQ_SEEN_LOOP = GINT_TO_POINTER(-1);
 
-	for (i = 0; i < bb->in_count; ++i) {
-		in_bb = bb->in_bb [i];
-
-		if (in_bb->last_seq_point) {
-			int src_index = in_bb->last_seq_point->backend.size;
-			int dst_index = ins->backend.size;
-
-			/* bb->in_bb might contain duplicates */
-			for (l = next [src_index]; l; l = l->next)
-				if (GPOINTER_TO_UINT (l->data) == dst_index)
-					break;
-			if (!l)
-				next [src_index] = g_slist_append (next [src_index], GUINT_TO_POINTER (dst_index));
-		} else {
-			/* Have to look at its predecessors */
-			if (depth < 5)
-				collect_pred_seq_points (in_bb, ins, next, depth + 1);
+	GArray *predecessors = g_array_new (FALSE, TRUE, sizeof (gpointer));
+	GHashTable *seen = g_hash_table_new_full (g_direct_hash, NULL, NULL, NULL);
+
+	// Insert/remove sentinel into the memoize table to detect loops containing bb
+	bb->pred_seq_points = MONO_SEQ_SEEN_LOOP;
+
+	for (int i = 0; i < bb->in_count; ++i) {
+		MonoBasicBlock *in_bb = bb->in_bb [i];
+		
+		// This bb has the last seq point, append it and continue
+		if (in_bb->last_seq_point != NULL) {
+			predecessors = g_array_append_val (predecessors, in_bb->last_seq_point);
+			continue;
+		}
+
+		// We've looped or handled this before, exit early.
+		// No last sequence points to find.
+		if (in_bb->pred_seq_points == MONO_SEQ_SEEN_LOOP)
+			continue;
+
+		// Take sequence points from incoming basic blocks
+	
+		if (in_bb == cfg->bb_entry)
+			continue;
+
+		if (in_bb->pred_seq_points == NULL)
+			recursively_make_pred_seq_points (cfg, in_bb);
+
+		// Union sequence points with incoming bb's
+		for (int i=0; i < in_bb->num_pred_seq_points; i++) {
+			if (!g_hash_table_lookup (seen, in_bb->pred_seq_points [i])) {
+				g_array_append_val (predecessors, in_bb->pred_seq_points [i]);
+				g_hash_table_insert (seen, in_bb->pred_seq_points [i], (gpointer)&MONO_SEQ_SEEN_LOOP);
+			}
 		}
+		// predecessors = g_array_append_vals (predecessors, in_bb->pred_seq_points, in_bb->num_pred_seq_points);
 	}
+
+	g_hash_table_destroy (seen);
+
+	if (predecessors->len != 0) {
+		bb->pred_seq_points = (MonoInst **)mono_mempool_alloc0 (cfg->mempool, sizeof (MonoInst *) * predecessors->len);
+		bb->num_pred_seq_points = predecessors->len;
+
+		for (int newer = 0; newer < bb->num_pred_seq_points; newer++) {
+			bb->pred_seq_points [newer] = g_array_index(predecessors, gpointer, newer);
+		}
+	} 
+
+	g_free (predecessors);
+}
+
+static void
+collect_pred_seq_points (MonoCompile *cfg, MonoBasicBlock *bb, MonoInst *ins, GSList **next)
+{
+	// Doesn't have a last sequence point, must find from incoming basic blocks
+	if (bb->pred_seq_points == NULL && bb != cfg->bb_entry)
+		recursively_make_pred_seq_points (cfg, bb);
+
+	for (int i = 0; i < bb->num_pred_seq_points; i++)
+		insert_pred_seq_point (bb->pred_seq_points [i], ins, next);
+
+	return;
 }
 
 void
@@ -92,7 +150,7 @@ mono_save_seq_point_info (MonoCompile *cfg)
 					next [last->backend.size] = g_slist_append (next [last->backend.size], GUINT_TO_POINTER (ins->backend.size));
 				} else {
 					/* Link with the last bb in the previous bblocks */
-					collect_pred_seq_points (bb, ins, next, 0);
+					collect_pred_seq_points (cfg, bb, ins, next);
 				}
 
 				last = ins;
@@ -294,11 +352,3 @@ mono_bb_deduplicate_op_il_seq_points (MonoCompile *cfg, MonoBasicBlock *bb)
 		MONO_REMOVE_INS (bb, prev);
 	};
 }
-
-void
-mono_image_get_aot_seq_point_path (MonoImage *image, char **str)
-{
-	int size = strlen (image->name) + strlen (SEQ_POINT_AOT_EXT) + 1;
-	*str = (char *)g_malloc (size);
-	g_sprintf (*str, "%s%s", image->name, SEQ_POINT_AOT_EXT);
-}