X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=nodestack.h;h=5351d6c7e7b4eb693f6af5bbecc8c4c41f1094ff;hb=4e8626fa3721aededd84133382625e20ae6490cf;hp=59da8a1f1f04971f709cfe0dd7b79d187ed4593b;hpb=b8bcaaa5a4b4d2413e3a0f419bbb91c540b28e50;p=model-checker.git

diff --git a/nodestack.h b/nodestack.h
index 59da8a1..5351d6c 100644
--- a/nodestack.h
+++ b/nodestack.h
@@ -1,3 +1,7 @@
+/** @file nodestack.h
+ *  @brief Stack of operations for use in backtracking.
+*/
+
 #ifndef __NODESTACK_H__
 #define __NODESTACK_H__
 
@@ -9,9 +13,20 @@
 
 class ModelAction;
 
+typedef std::list< ModelAction *, MyAlloc< ModelAction * > > action_set_t;
+
+/**
+ * @brief A single node in a NodeStack
+ *
+ * Represents a single node in the NodeStack. Each Node is associated with up
+ * to one action and up to one parent node. A node holds information
+ * regarding the last action performed (the "associated action"), the thread
+ * choices that have been explored (explored_children) and should be explored
+ * (backtrack), and the actions that the last action may read from.
+ */
 class Node {
 public:
-	Node(ModelAction *act = NULL, int nthreads = 1);
+	Node(ModelAction *act = NULL, Node *par = NULL, int nthreads = 1);
 	~Node();
 	/* return true = thread choice has already been explored */
 	bool has_been_explored(thread_id_t tid);
@@ -24,6 +39,12 @@ public:
 	bool is_enabled(Thread *t);
 	ModelAction * get_action() { return action; }
 
+	/** @return the parent Node to this Node; that is, the action that
+	 * occurred previously in the stack. */
+	Node * get_parent() const { return parent; }
+
+	void add_read_from(ModelAction *act);
+
 	void print();
 
 	MEMALLOC
@@ -31,13 +52,27 @@ private:
 	void explore(thread_id_t tid);
 
 	ModelAction *action;
+	Node *parent;
 	int num_threads;
 	std::vector< bool, MyAlloc<bool> > explored_children;
 	std::vector< bool, MyAlloc<bool> > backtrack;
+	int numBacktracks;
+
+	/** The set of ModelActions that this the action at this Node may read
+	 *  from. Only meaningful if this Node represents a 'read' action. */
+	action_set_t may_read_from;
 };
 
-typedef std::list<class Node *, MyAlloc< class Node * > > node_list_t;
+typedef std::list< Node *, MyAlloc< Node * > > node_list_t;
 
+/**
+ * @brief A stack of nodes
+ *
+ * Holds a Node linked-list that can be used for holding backtracking,
+ * may-read-from, and replay information. It is used primarily as a
+ * stack-like structure, in that backtracking points and replay nodes are
+ * only removed from the top (most recent).
+ */
 class NodeStack {
 public:
 	NodeStack();