X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=action.cc;h=ca1285612b00c75fd7294bee5af80d3aa52a3468;hb=1b793f0683aff025afe2e19519572e3599575a19;hp=5e050810e7526408828b27c74cad76fcdef95a4b;hpb=e60d8c23d30a0dfe66b8426f7f2ecf576e812028;p=model-checker.git

diff --git a/action.cc b/action.cc
index 5e05081..ca12856 100644
--- a/action.cc
+++ b/action.cc
@@ -36,6 +36,9 @@ ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
 	cv(NULL),
 	sleep_flag(false)
 {
+	/* References to NULL atomic variables can end up here */
+	ASSERT(loc || type == MODEL_FIXUP_RELSEQ);
+
 	Thread *t = thread ? thread : thread_current();
 	this->tid = t->get_id();
 }
@@ -111,6 +114,11 @@ bool ModelAction::is_write() const
 	return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT;
 }
 
+bool ModelAction::could_be_write() const
+{
+	return is_write() || is_rmwr();
+}
+
 bool ModelAction::is_rmwr() const
 {
 	return type == ATOMIC_RMWR;
@@ -217,11 +225,11 @@ bool ModelAction::could_synchronize_with(const ModelAction *act) const
 
 	// Explore interleavings of seqcst writes to guarantee total order
 	// of seq_cst operations that don't commute
-	if ((is_write() || act->is_write()) && is_seqcst() && act->is_seqcst())
+	if ((could_be_write() || act->could_be_write()) && is_seqcst() && act->is_seqcst())
 		return true;
 
 	// Explore synchronizing read/write pairs
-	if (is_read() && is_acquire() && act->is_write() && act->is_release())
+	if (is_read() && is_acquire() && act->could_be_write() && act->is_release())
 		return true;
 
 	// Otherwise handle by reads_from relation