promise: record multiple readers in the same Promise

[c11tester.git] / promise.cc

diff --git a/promise.cc b/promise.cc
index 86c3c584f12ba884d190c792b10f459e225c8330..23b92cd4186a59bb7a5b7c411668501afc4447e7 100644 (file)
--- a/promise.cc
+++ b/promise.cc
@@ -15,13 +15,38 @@
 Promise::Promise(ModelAction *read, struct future_value fv) :
        num_available_threads(0),
        fv(fv),
-       read(read),
+       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.
@@ -76,7 +101,7 @@ bool Promise::thread_is_available(thread_id_t tid) const
 /** @brief Print debug info about the Promise */
 void Promise::print() const
 {
-       model_print("Promised value %#" PRIx64 ", read from thread %d, available threads to resolve: ", fv.value, id_to_int(read->get_tid()));
+       model_print("Promised value %#" PRIx64 ", first read from thread %d, available threads to resolve: ", fv.value, id_to_int(get_reader(0)->get_tid()));
        for (unsigned int i = 0; i < available_thread.size(); i++)
                if (available_thread[i])
                        model_print("[%d]", i);
@@ -102,7 +127,7 @@ bool Promise::has_failed() const
  */
 bool Promise::is_compatible(const ModelAction *act) const
 {
-       return thread_is_available(act->get_tid()) && read->same_var(act);
+       return thread_is_available(act->get_tid()) && get_reader(0)->same_var(act);
 }
 
 /**