2 * @brief Stack of operations for use in backtracking.
5 #ifndef __NODESTACK_H__
6 #define __NODESTACK_H__
17 * A flag used for the promise counting/combination problem within a node,
18 * denoting whether a particular Promise is
19 * <ol><li>@b applicable: can be satisfied by this Node's ModelAction and</li>
20 * <li>@b fulfilled: satisfied by this Node's ModelAction under the current
21 * configuration.</li></ol>
24 PROMISE_IGNORE = 0, /**< This promise is inapplicable; ignore it */
25 PROMISE_UNFULFILLED, /**< This promise is applicable but unfulfilled */
26 PROMISE_FULFILLED /**< This promise is applicable and fulfilled */
30 * @brief A single node in a NodeStack
32 * Represents a single node in the NodeStack. Each Node is associated with up
33 * to one action and up to one parent node. A node holds information
34 * regarding the last action performed (the "associated action"), the thread
35 * choices that have been explored (explored_children) and should be explored
36 * (backtrack), and the actions that the last action may read from.
40 Node(ModelAction *act = NULL, Node *par = NULL, int nthreads = 1);
42 /* return true = thread choice has already been explored */
43 bool has_been_explored(thread_id_t tid);
44 /* return true = backtrack set is empty */
45 bool backtrack_empty();
47 void explore_child(ModelAction *act);
48 /* return false = thread was already in backtrack */
49 bool set_backtrack(thread_id_t id);
50 thread_id_t get_next_backtrack();
51 bool is_enabled(Thread *t);
52 ModelAction * get_action() { return action; }
54 /** @return the parent Node to this Node; that is, the action that
55 * occurred previously in the stack. */
56 Node * get_parent() const { return parent; }
58 bool add_future_value(uint64_t value);
59 uint64_t get_future_value();
60 bool increment_future_value();
61 bool future_value_empty();
63 void add_read_from(const ModelAction *act);
64 const ModelAction * get_read_from();
65 bool increment_read_from();
66 bool read_from_empty();
68 void set_promise(unsigned int i);
69 bool get_promise(unsigned int i);
70 bool increment_promise();
74 void print_may_read_from();
78 void explore(thread_id_t tid);
83 std::vector< bool, MyAlloc<bool> > explored_children;
84 std::vector< bool, MyAlloc<bool> > backtrack;
87 /** The set of ModelActions that this the action at this Node may read
88 * from. Only meaningful if this Node represents a 'read' action. */
89 std::vector< const ModelAction *, MyAlloc< const ModelAction * > > may_read_from;
91 unsigned int read_from_index;
93 std::vector< uint64_t, MyAlloc< uint64_t > > future_values;
94 std::vector< promise_t, MyAlloc<promise_t> > promises;
95 unsigned int future_index;
98 typedef std::list< Node *, MyAlloc< Node * > > node_list_t;
101 * @brief A stack of nodes
103 * Holds a Node linked-list that can be used for holding backtracking,
104 * may-read-from, and replay information. It is used primarily as a
105 * stack-like structure, in that backtracking points and replay nodes are
106 * only removed from the top (most recent).
112 ModelAction * explore_action(ModelAction *act);
115 void reset_execution();
116 void pop_restofstack(int numAhead);
117 int get_total_nodes() { return total_nodes; }
123 node_list_t node_list;
124 node_list_t::iterator iter;
129 #endif /* __NODESTACK_H__ */