2 * @brief Stack of operations for use in backtracking.
5 #ifndef __NODESTACK_H__
6 #define __NODESTACK_H__
14 #include "modeltypes.h"
21 * A flag used for the promise counting/combination problem within a node,
22 * denoting whether a particular Promise is
23 * <ol><li>@b applicable: can be satisfied by this Node's ModelAction and</li>
24 * <li>@b fulfilled: satisfied by this Node's ModelAction under the current
25 * configuration.</li></ol>
28 #define PROMISE_IGNORE 0 /**< This promise is inapplicable; ignore it */
29 #define PROMISE_UNFULFILLED 1 /**< This promise is applicable but unfulfilled */
30 #define PROMISE_FULFILLED 2 /**< This promise is applicable and fulfilled */
31 #define PROMISE_MASK 0xf
32 #define PROMISE_RMW 0x10
34 typedef int promise_t;
38 modelclock_t expiration;
41 struct fairness_info {
42 unsigned int enabled_count;
49 * @brief A single node in a NodeStack
51 * Represents a single node in the NodeStack. Each Node is associated with up
52 * to one action and up to one parent node. A node holds information
53 * regarding the last action performed (the "associated action"), the thread
54 * choices that have been explored (explored_children) and should be explored
55 * (backtrack), and the actions that the last action may read from.
59 Node(ModelAction *act = NULL, Node *par = NULL, int nthreads = 2, Node *prevfairness = NULL);
61 /* return true = thread choice has already been explored */
62 bool has_been_explored(thread_id_t tid);
63 /* return true = backtrack set is empty */
64 bool backtrack_empty();
66 void explore_child(ModelAction *act, enabled_type_t * is_enabled);
67 /* return false = thread was already in backtrack */
68 bool set_backtrack(thread_id_t id);
69 thread_id_t get_next_backtrack();
70 bool is_enabled(Thread *t);
71 bool is_enabled(thread_id_t tid);
72 enabled_type_t enabled_status(thread_id_t tid);
74 ModelAction * get_action() { return action; }
75 bool has_priority(thread_id_t tid);
76 int get_num_threads() {return num_threads;}
77 /** @return the parent Node to this Node; that is, the action that
78 * occurred previously in the stack. */
79 Node * get_parent() const { return parent; }
81 bool add_future_value(uint64_t value, modelclock_t expiration);
82 uint64_t get_future_value();
83 modelclock_t get_future_value_expiration();
84 bool increment_future_value();
85 bool future_value_empty();
87 void add_read_from(const ModelAction *act);
88 const ModelAction * get_read_from();
89 bool increment_read_from();
90 bool read_from_empty();
91 int get_read_from_size();
92 const ModelAction * get_read_from_at(int i);
94 void set_promise(unsigned int i, bool is_rmw);
95 bool get_promise(unsigned int i);
96 bool increment_promise();
98 enabled_type_t *get_enabled_array() {return enabled_array;}
100 void set_misc_max(int i);
102 bool increment_misc();
105 void add_relseq_break(const ModelAction *write);
106 const ModelAction * get_relseq_break();
107 bool increment_relseq_break();
108 bool relseq_break_empty();
111 void print_may_read_from();
115 void explore(thread_id_t tid);
120 std::vector< bool, ModelAlloc<bool> > explored_children;
121 std::vector< bool, ModelAlloc<bool> > backtrack;
122 std::vector< struct fairness_info, ModelAlloc< struct fairness_info> > fairness;
124 enabled_type_t *enabled_array;
126 /** The set of ModelActions that this the action at this Node may read
127 * from. Only meaningful if this Node represents a 'read' action. */
128 std::vector< const ModelAction *, ModelAlloc< const ModelAction * > > may_read_from;
130 unsigned int read_from_index;
132 std::vector< struct future_value, ModelAlloc<struct future_value> > future_values;
133 std::vector< promise_t, ModelAlloc<promise_t> > promises;
136 std::vector< const ModelAction *, ModelAlloc<const ModelAction *> > relseq_break_writes;
137 int relseq_break_index;
143 typedef std::vector< Node *, ModelAlloc< Node * > > node_list_t;
146 * @brief A stack of nodes
148 * Holds a Node linked-list that can be used for holding backtracking,
149 * may-read-from, and replay information. It is used primarily as a
150 * stack-like structure, in that backtracking points and replay nodes are
151 * only removed from the top (most recent).
157 ModelAction * explore_action(ModelAction *act, enabled_type_t * is_enabled);
160 void reset_execution();
161 void pop_restofstack(int numAhead);
162 int get_total_nodes() { return total_nodes; }
168 node_list_t node_list;
174 #endif /* __NODESTACK_H__ */