model: utilize CycleGraph 'addEdge()' status

The mo_graph is only modified if addEdge() returns true. Utilize this
information.

diff --git a/model.cc b/model.cc
index 15f1831627e0621896fadc3638ec27e6814cfc07..6739d2c85ee2ca51dd3963c471c811e12f0711b3 100644 (file)
--- a/model.cc
+++ b/model.cc
@@ -1575,22 +1575,19 @@ bool ModelChecker::r_modification_order(ModelAction *curr, const rf_type *rf)
                                /* C++, Section 29.3 statement 5 */
                                if (curr->is_seqcst() && last_sc_fence_thread_local &&
                                                *act < *last_sc_fence_thread_local) {
-                                       mo_graph->addEdge(act, rf);
-                                       added = true;
+                                       added = mo_graph->addEdge(act, rf) || added;
                                        break;
                                }
                                /* C++, Section 29.3 statement 4 */
                                else if (act->is_seqcst() && last_sc_fence_local &&
                                                *act < *last_sc_fence_local) {
-                                       mo_graph->addEdge(act, rf);
-                                       added = true;
+                                       added = mo_graph->addEdge(act, rf) || added;
                                        break;
                                }
                                /* C++, Section 29.3 statement 6 */
                                else if (last_sc_fence_thread_before &&
                                                *act < *last_sc_fence_thread_before) {
-                                       mo_graph->addEdge(act, rf);
-                                       added = true;
+                                       added = mo_graph->addEdge(act, rf) || added;
                                        break;
                                }
                        }
@@ -1602,8 +1599,7 @@ bool ModelChecker::r_modification_order(ModelAction *curr, const rf_type *rf)
                        if (act->happens_before(curr) && act != curr) {
                                if (act->is_write()) {
                                        if (!act->equals(rf)) {
-                                               mo_graph->addEdge(act, rf);
-                                               added = true;
+                                               added = mo_graph->addEdge(act, rf) || added;
                                        }
                                } else {
                                        const ModelAction *prevreadfrom = act->get_reads_from();
@@ -1612,8 +1608,7 @@ bool ModelChecker::r_modification_order(ModelAction *curr, const rf_type *rf)
                                                continue;
 
                                        if (!prevreadfrom->equals(rf)) {
-                                               mo_graph->addEdge(prevreadfrom, rf);
-                                               added = true;
+                                               added = mo_graph->addEdge(prevreadfrom, rf) || added;
                                        }
                                }
                                break;
@@ -1722,8 +1717,7 @@ bool ModelChecker::w_modification_order(ModelAction *curr)
                         so we are initialized. */
                ModelAction *last_seq_cst = get_last_seq_cst_write(curr);
                if (last_seq_cst != NULL) {
-                       mo_graph->addEdge(last_seq_cst, curr);
-                       added = true;
+                       added = mo_graph->addEdge(last_seq_cst, curr) || added;
                }
        }
 
@@ -1766,8 +1760,7 @@ bool ModelChecker::w_modification_order(ModelAction *curr)
                        /* C++, Section 29.3 statement 7 */
                        if (last_sc_fence_thread_before && act->is_write() &&
                                        *act < *last_sc_fence_thread_before) {
-                               mo_graph->addEdge(act, curr);
-                               added = true;
+                               added = mo_graph->addEdge(act, curr) || added;
                                break;
                        }
 
@@ -1783,14 +1776,13 @@ bool ModelChecker::w_modification_order(ModelAction *curr)
                                 *   readfrom(act) --mo--> act
                                 */
                                if (act->is_write())
-                                       mo_graph->addEdge(act, curr);
+                                       added = mo_graph->addEdge(act, curr) || added;
                                else if (act->is_read()) {
                                        //if previous read accessed a null, just keep going
                                        if (act->get_reads_from() == NULL)
                                                continue;
-                                       mo_graph->addEdge(act->get_reads_from(), curr);
+                                       added = mo_graph->addEdge(act->get_reads_from(), curr) || added;
                                }
-                               added = true;
                                break;
                        } else if (act->is_read() && !act->could_synchronize_with(curr) &&
                                                     !act->same_thread(curr)) {