+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+
#include "promise.h"
-#include "model.h"
+#include "execution.h"
#include "schedule.h"
+#include "action.h"
+#include "threads-model.h"
-bool Promise::increment_threads(thread_id_t tid) {
- unsigned int id=id_to_int(tid);
- if ( id >= synced_thread.size() ) {
- synced_thread.resize(id+1, false);
- }
- if (synced_thread[id])
+/**
+ * @brief Promise constructor
+ * @param execution The execution which is creating this Promise
+ * @param read The read which reads from a promised future value
+ * @param fv The future value that is promised
+ */
+Promise::Promise(const ModelExecution *execution, ModelAction *read, struct future_value fv) :
+ execution(execution),
+ num_available_threads(0),
+ fv(fv),
+ readers(1, read),
+ write(NULL)
+{
+ add_thread(fv.tid);
+ eliminate_thread(read->get_tid());
+}
+
+/**
+ * Add a reader that reads from this Promise. Must be added in an order
+ * consistent with execution order.
+ *
+ * @param reader The ModelAction that reads from this promise. Must be a read.
+ * @return True if this new reader has invalidated the promise; false otherwise
+ */
+bool Promise::add_reader(ModelAction *reader)
+{
+ readers.push_back(reader);
+ return eliminate_thread(reader->get_tid());
+}
+
+/**
+ * Access a reader that read from this Promise. Readers must be inserted in
+ * order by execution order, so they can be returned in this order.
+ *
+ * @param i The index of the reader to return
+ * @return The i'th reader of this Promise
+ */
+ModelAction * Promise::get_reader(unsigned int i) const
+{
+ return i < readers.size() ? readers[i] : NULL;
+}
+
+/**
+ * Eliminate a thread which no longer can satisfy this promise. Once all
+ * enabled threads have been eliminated, this promise is unresolvable.
+ *
+ * @param tid The thread ID of the thread to eliminate
+ * @return True, if this elimination has invalidated the promise; false
+ * otherwise
+ */
+bool Promise::eliminate_thread(thread_id_t tid)
+{
+ unsigned int id = id_to_int(tid);
+ if (!thread_is_available(tid))
return false;
-
- synced_thread[id]=true;
- unsigned int sync_size=synced_thread.size();
- int promise_tid=id_to_int(read->get_tid());
- for(unsigned int i=1;i<model->get_num_threads();i++) {
- if ((i >= sync_size || !synced_thread[i]) && ( (int)i != promise_tid ) && model->is_enabled(int_to_id(i))) {
- return false;
- }
+
+ available_thread[id] = false;
+ num_available_threads--;
+ return has_failed();
+}
+
+/**
+ * Add a thread which may resolve this promise
+ *
+ * @param tid The thread ID
+ */
+void Promise::add_thread(thread_id_t tid)
+{
+ unsigned int id = id_to_int(tid);
+ if (id >= available_thread.size())
+ available_thread.resize(id + 1, false);
+ if (!available_thread[id]) {
+ available_thread[id] = true;
+ num_available_threads++;
}
- return true;
}
-bool Promise::check_promise() {
- unsigned int sync_size=synced_thread.size();
- for(unsigned int i=1;i<model->get_num_threads();i++) {
- if ((i >= sync_size || !synced_thread[i]) && model->is_enabled(int_to_id(i))) {
- return false;
+/**
+ * Check if a thread is available for resolving this promise. That is, the
+ * thread must have been previously marked for resolving this promise, and it
+ * cannot have been eliminated due to synchronization, etc.
+ *
+ * @param tid Thread ID of the thread to check
+ * @return True if the thread is available; false otherwise
+ */
+bool Promise::thread_is_available(thread_id_t tid) const
+{
+ unsigned int id = id_to_int(tid);
+ if (id >= available_thread.size())
+ return false;
+ return available_thread[id];
+}
+
+/**
+ * @brief Get an upper bound on the number of available threads
+ *
+ * Gets an upper bound on the number of threads in the available threads set,
+ * useful for iterating over "thread_is_available()".
+ *
+ * @return The upper bound
+ */
+unsigned int Promise::max_available_thread_idx() const
+{
+ return available_thread.size();
+}
+
+/** @brief Print debug info about the Promise */
+void Promise::print() const
+{
+ model_print("Promised value %#" PRIx64 ", first read from thread %d, available threads to resolve: ",
+ fv.value, id_to_int(get_reader(0)->get_tid()));
+ bool failed = true;
+ for (unsigned int i = 0; i < available_thread.size(); i++)
+ if (available_thread[i]) {
+ model_print("[%d]", i);
+ failed = false;
}
- }
- return true;
+ if (failed)
+ model_print("(none)");
+ model_print("\n");
+}
+
+/**
+ * Check if this promise has failed. A promise can fail when all threads which
+ * could possibly satisfy the promise have been eliminated.
+ *
+ * @return True, if this promise has failed; false otherwise
+ */
+bool Promise::has_failed() const
+{
+ return num_available_threads == 0;
+}
+
+/**
+ * @brief Check if an action's thread and location are compatible for resolving
+ * this promise
+ * @param act The action to check against
+ * @return True if we are compatible; false otherwise
+ */
+bool Promise::is_compatible(const ModelAction *act) const
+{
+ return thread_is_available(act->get_tid()) && get_reader(0)->same_var(act);
+}
+
+/**
+ * @brief Check if an action's thread and location are compatible for resolving
+ * this promise, and that the promise is thread-exclusive
+ * @param act The action to check against
+ * @return True if we are compatible and exclusive; false otherwise
+ */
+bool Promise::is_compatible_exclusive(const ModelAction *act) const
+{
+ return get_num_available_threads() == 1 && is_compatible(act);
+}
+
+/**
+ * @brief Check if a store's value matches this Promise
+ * @param write The store to check
+ * @return True if the store's written value matches this Promise
+ */
+bool Promise::same_value(const ModelAction *write) const
+{
+ return get_value() == write->get_write_value();
+}
+
+/**
+ * @brief Check if a ModelAction's location matches this Promise
+ * @param act The ModelAction to check
+ * @return True if the action's location matches this Promise
+ */
+bool Promise::same_location(const ModelAction *act) const
+{
+ return get_reader(0)->same_var(act);
+}
+
+/** @brief Get this Promise's index within the execution's promise array */
+int Promise::get_index() const
+{
+ return execution->get_promise_number(this);
}