promise: rename has_sync_thread() -> thread_is_eliminated()

[model-checker.git] / promise.cc

diff --git a/promise.cc b/promise.cc
index b051ef078bf8dbe92e817cb75b06a593b46ab1ca..3b2aa960f967bb389d48b24fe61e0d4f62664471 100644 (file)
--- a/promise.cc
+++ b/promise.cc
@@ -1,8 +1,41 @@
 #include "promise.h"
+#include "model.h"
+#include "schedule.h"
 
-Promise::Promise(ModelAction *act, uint64_t value) {
-       this->value=value;
-       this->read=act;
-       this->numthreads=1;
+/**
+ * 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 (id >= eliminated_thread.size())
+               eliminated_thread.resize(id + 1, false);
+       if (eliminated_thread[id])
+               return false;
+
+       eliminated_thread[id] = true;
+       return has_failed();
 }
 
+/**
+ * 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
+{
+       unsigned int size = eliminated_thread.size();
+       int promise_tid = id_to_int(read->get_tid());
+       for (unsigned int i = 1; i < model->get_num_threads(); i++) {
+               if ((i >= size || !eliminated_thread[i]) && ((int)i != promise_tid) && model->is_enabled(int_to_id(i))) {
+                       return false;
+               }
+       }
+       return true;
+}