some changes towards reading from future writes

[model-checker.git] / nodestack.h

diff --git a/nodestack.h b/nodestack.h
index 11440e5ae5680af381842c3ef81e637dd0e16ee9..16264a2bbf800c6832e312cab644e85febb4f566 100644 (file)
--- a/nodestack.h
+++ b/nodestack.h
@@ -7,15 +7,24 @@
 
 #include <list>
 #include <vector>
-#include <set>
 #include <cstddef>
 #include "threads.h"
 #include "mymemory.h"
 
 class ModelAction;
 
-typedef std::set< ModelAction *, std::less< ModelAction *>, MyAlloc< ModelAction * > > action_set_t;
-
+typedef std::vector< const ModelAction *, MyAlloc< const ModelAction * > > readfrom_set_t;
+typedef std::vector< uint64_t, MyAlloc< uint64_t > > futurevalues_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, Node *par = NULL, int nthreads = 1);
@@ -24,6 +33,8 @@ public:
        bool has_been_explored(thread_id_t tid);
        /* return true = backtrack set is empty */
        bool backtrack_empty();
+       bool readsfrom_empty();
+       bool futurevalues_empty();
        void explore_child(ModelAction *act);
        /* return false = thread was already in backtrack */
        bool set_backtrack(thread_id_t id);
@@ -35,9 +46,15 @@ public:
         * occurred previously in the stack. */
        Node * get_parent() const { return parent; }
 
-       void add_read_from(ModelAction *act);
+       void add_future_value(uint64_t value);
+       void add_read_from(const ModelAction *act);
+       const ModelAction * get_read_from();
+       uint64_t get_future_value();
+       bool increment_read_from();
+       bool increment_future_values();
 
        void print();
+       void print_may_read_from();
 
        MEMALLOC
 private:
@@ -52,11 +69,23 @@ private:
 
        /** 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;
+       readfrom_set_t may_read_from;
+       unsigned int read_from_index;
+
+       futurevalues_t future_values;
+       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();
@@ -65,7 +94,7 @@ public:
        Node * get_head();
        Node * get_next();
        void reset_execution();
-
+       void pop_restofstack(int numAhead);
        int get_total_nodes() { return total_nodes; }
 
        void print();