cyclegraph: improve comments, use initializer list

[model-checker.git] / nodestack.h

diff --git a/nodestack.h b/nodestack.h
index a73ce44034fba9bc44d76ebe27f8912c21132c83..fc3bf1d0911c8e43da840332ffa0b41758431fd9 100644 (file)
--- a/nodestack.h
+++ b/nodestack.h
@@ -13,14 +13,28 @@
 
 class ModelAction;
 
+typedef std::vector< const ModelAction *, MyAlloc< const ModelAction * > > readfrom_set_t;
+typedef std::vector< uint64_t, MyAlloc< uint64_t > > futurevalues_t;
+typedef std::vector< uint32_t, MyAlloc< uint32_t > > promises_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);
        /* return true = backtrack set is empty */
        bool backtrack_empty();
+
        void explore_child(ModelAction *act);
        /* return false = thread was already in backtrack */
        bool set_backtrack(thread_id_t id);
@@ -28,21 +42,59 @@ 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; }
+
+       bool add_future_value(uint64_t value);
+       uint64_t get_future_value();
+       bool increment_future_value();
+       bool future_value_empty();
+
+       void add_read_from(const ModelAction *act);
+       const ModelAction * get_read_from();
+       bool increment_read_from();
+       bool read_from_empty();
+
+       void set_promise(uint32_t i);
+       bool get_promise(uint32_t i);
+       bool increment_promise();
+       bool promise_empty();
+
        void print();
+       void print_may_read_from();
 
        MEMALLOC
 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. */
+       readfrom_set_t may_read_from;
+       unsigned int read_from_index;
+
+       futurevalues_t future_values;
+       promises_t promises;
+       unsigned int future_index;
 };
 
-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();
@@ -51,7 +103,7 @@ public:
        Node * get_head();
        Node * get_next();
        void reset_execution();
-
+       void pop_restofstack(int numAhead);
        int get_total_nodes() { return total_nodes; }
 
        void print();