X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=action.cc;h=be8c4a6c0cdc69bde75fd08436a33705fa9157af;hb=dd989c16bf4ede61142d79737a8f6568aa153fa2;hp=5f83c3f5604524692e88e1c9478db7bb9f7216fc;hpb=a0db445e3ecfedce6a85b7b381416b5c363a0614;p=model-checker.git

diff --git a/action.cc b/action.cc
index 5f83c3f..be8c4a6 100644
--- a/action.cc
+++ b/action.cc
@@ -394,7 +394,9 @@ uint64_t ModelAction::get_reads_from_value() const
 	ASSERT(is_read());
 	if (reads_from)
 		return reads_from->get_write_value();
-	return reads_from_promise->get_value();
+	else if (reads_from_promise)
+		return reads_from_promise->get_value();
+	return VALUE_NONE; /* Only for new actions with no reads-from */
 }
 
 /**
@@ -414,6 +416,26 @@ uint64_t ModelAction::get_write_value() const
 	return value;
 }
 
+/**
+ * @brief Get the value returned by this action
+ *
+ * For atomic reads (including RMW), an operation returns the value it read.
+ * For atomic writes, an operation returns the value it wrote. For other
+ * operations, the return value varies (sometimes is a "don't care"), but the
+ * value is simply stored in the "value" field.
+ *
+ * @return This action's return value
+ */
+uint64_t ModelAction::get_return_value() const
+{
+	if (is_read())
+		return get_reads_from_value();
+	else if (is_write())
+		return get_write_value();
+	else
+		return value;
+}
+
 /** @return The Node associated with this ModelAction */
 Node * ModelAction::get_node() const
 {
@@ -546,14 +568,6 @@ void ModelAction::print() const
 		type_str = "unknown type";
 	}
 
-	uint64_t valuetoprint;
-	if (is_read())
-		valuetoprint = get_reads_from_value();
-	else if (is_write())
-		valuetoprint = get_write_value();
-	else
-		valuetoprint = value;
-
 	switch (this->order) {
 	case std::memory_order_relaxed:
 		mo_str = "relaxed";
@@ -576,7 +590,7 @@ void ModelAction::print() const
 	}
 
 	model_print("(%4d) Thread: %-2d   Action: %-13s   MO: %7s  Loc: %14p   Value: %-#18" PRIx64,
-			seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
+			seq_number, id_to_int(tid), type_str, mo_str, location, get_return_value());
 	if (is_read()) {
 		if (reads_from)
 			model_print("  Rf: %-3d", reads_from->get_seq_number());
@@ -611,3 +625,43 @@ unsigned int ModelAction::hash() const
 		hash ^= reads_from->get_seq_number();
 	return hash;
 }
+
+/**
+ * @brief Checks the NodeStack to see if a ModelAction is in our may-read-from set
+ * @param write The ModelAction to check for
+ * @return True if the ModelAction is found; false otherwise
+ */
+bool ModelAction::may_read_from(const ModelAction *write) const
+{
+	for (int i = 0; i < node->get_read_from_past_size(); i++)
+		if (node->get_read_from_past(i) == write)
+			return true;
+	return false;
+}
+
+/**
+ * @brief Checks the NodeStack to see if a Promise is in our may-read-from set
+ * @param promise The Promise to check for
+ * @return True if the Promise is found; false otherwise
+ */
+bool ModelAction::may_read_from(const Promise *promise) const
+{
+	for (int i = 0; i < node->get_read_from_promise_size(); i++)
+		if (node->get_read_from_promise(i) == promise)
+			return true;
+	return false;
+}
+
+/**
+ * Only valid for LOCK, TRY_LOCK, UNLOCK, and WAIT operations.
+ * @return The mutex operated on by this action, if any; otherwise NULL
+ */
+std::mutex * ModelAction::get_mutex() const
+{
+	if (is_trylock() || is_lock() || is_unlock())
+		return (std::mutex *)get_location();
+	else if (is_wait())
+		return (std::mutex *)get_value();
+	else
+		return NULL;
+}