Merge pull request #8476 from AcKoucher/mpl-redundant-connections

mpl: avoid redundant connections

Author: eder-matheus

src/mpl/src/clusterEngine.cpp

@@ -1027,9 +1027,11 @@ void ClusteringEngine::buildDataFlowConnections()
     for (int hops = 0; hops < max_num_of_hops_; hops++) {
       std::set<int> sink_clusters = computeSinks(insts[hops]);
       const float conn_weight = computeConnWeight(hops);
-      for (auto& sink : sink_clusters) {
-        Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink);
-        connect(driver_cluster, sink_cluster, conn_weight);
+      for (const int sink_id : sink_clusters) {
+        if (driver_id != sink_id) {
+          Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink_id);
+          connect(driver_cluster, sink_cluster, conn_weight);
+        }
       }
     }
   }
@@ -1042,9 +1044,11 @@ void ClusteringEngine::buildDataFlowConnections()
     for (int hops = 0; hops < max_num_of_hops_; hops++) {
       std::set<int> sink_clusters = computeSinks(insts[hops]);
       const float conn_weight = computeConnWeight(hops);
-      for (auto& sink : sink_clusters) {
-        Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink);
-        connect(driver_cluster, sink_cluster, conn_weight);
+      for (const int sink_id : sink_clusters) {
+        if (driver_id != sink_id) {
+          Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink_id);
+          connect(driver_cluster, sink_cluster, conn_weight);
+        }
       }
     }
   }
@@ -1057,9 +1061,11 @@ void ClusteringEngine::buildDataFlowConnections()
     for (int hops = 0; hops < max_num_of_hops_; hops++) {
       std::set<int> sink_clusters = computeSinks(insts[hops]);
       const float conn_weight = computeConnWeight(hops);
-      for (auto& sink : sink_clusters) {
-        Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink);
-        connect(driver_cluster, sink_cluster, conn_weight);
+      for (const int sink_id : sink_clusters) {
+        if (driver_id != sink_id) {
+          Cluster* sink_cluster = tree_->maps.id_to_cluster.at(sink_id);
+          connect(driver_cluster, sink_cluster, conn_weight);
+        }
       }
     }
   }
@@ -1869,7 +1875,13 @@ bool ClusteringEngine::attemptMerge(Cluster* receiver, Cluster* incomer)
       for (const auto& [cluster_id, connection_weight] : incomer_connections) {
         Cluster* cluster = tree_->maps.id_to_cluster.at(cluster_id);
         cluster->removeConnection(incomer_id);
-        cluster->addConnection(receiver, connection_weight);
+
+        // If the incomer and the receiver were connected, we forget that
+        // connection, otherwise we'll end up with the receiver connected
+        // to itself.
+        if (cluster_id != receiver->getId()) {
+          cluster->addConnection(receiver, connection_weight);
+        }
       }
     }
 

src/mpl/test/guides2.defok

@@ -339,16 +339,16 @@ TRACKS Y 140 DO 282 STEP 3200 LAYER metal9 ;
 TRACKS X 190 DO 282 STEP 3200 LAYER metal10 ;
 TRACKS Y 140 DO 282 STEP 3200 LAYER metal10 ;
 COMPONENTS 10 ;
-    - U1 HM_100x400_4x4 + FIXED ( 665880 16610 ) S ;
-    - U10 HM_100x100_1x1 + FIXED ( 233880 448450 ) S ;
-    - U2 HM_100x100_1x1 + FIXED ( 17880 448450 ) S ;
-    - U3 HM_100x100_1x1 + FIXED ( 233880 664610 ) S ;
-    - U4 HM_100x100_1x1 + FIXED ( 233880 16550 ) FN ;
-    - U5 HM_100x100_1x1 + FIXED ( 233880 232430 ) FN ;
+    - U1 HM_100x400_4x4 + FIXED ( 665880 16590 ) FN ;
+    - U10 HM_100x100_1x1 + FIXED ( 17880 448450 ) S ;
+    - U2 HM_100x100_1x1 + FIXED ( 17880 16550 ) FN ;
+    - U3 HM_100x100_1x1 + FIXED ( 17880 664470 ) FN ;
+    - U4 HM_100x100_1x1 + FIXED ( 17880 232430 ) FN ;
+    - U5 HM_100x100_1x1 + FIXED ( 233880 448450 ) S ;
     - U6 HM_100x400_4x4 + FIXED ( 449880 16590 ) N ;
-    - U7 HM_100x100_1x1 + FIXED ( 17880 232430 ) N ;
-    - U8 HM_100x100_1x1 + FIXED ( 17880 664610 ) S ;
-    - U9 HM_100x100_1x1 + FIXED ( 17880 16550 ) FN ;
+    - U7 HM_100x100_1x1 + FIXED ( 233880 16550 ) N ;
+    - U8 HM_100x100_1x1 + FIXED ( 233880 664610 ) FS ;
+    - U9 HM_100x100_1x1 + FIXED ( 233880 232430 ) N ;
 END COMPONENTS
 NETS 12 ;
     - w1 ( U2 I1 ) ( U1 O1 ) + USE SIGNAL ;

src/mpl/test/macro_only.defok

@@ -339,16 +339,16 @@ TRACKS Y 140 DO 282 STEP 3200 LAYER metal9 ;
 TRACKS X 190 DO 282 STEP 3200 LAYER metal10 ;
 TRACKS Y 140 DO 282 STEP 3200 LAYER metal10 ;
 COMPONENTS 10 ;
-    - U1 HM_100x400_4x4 + FIXED ( 665880 16610 ) S ;
-    - U10 HM_100x100_1x1 + FIXED ( 233880 16550 ) FN ;
-    - U2 HM_100x100_1x1 + FIXED ( 449880 448450 ) S ;
-    - U3 HM_100x100_1x1 + FIXED ( 449880 664610 ) S ;
-    - U4 HM_100x100_1x1 + FIXED ( 449880 232430 ) FN ;
-    - U5 HM_100x100_1x1 + FIXED ( 449880 16550 ) FN ;
-    - U6 HM_100x400_4x4 + FIXED ( 17880 16610 ) S ;
-    - U7 HM_100x100_1x1 + FIXED ( 233880 448450 ) S ;
-    - U8 HM_100x100_1x1 + FIXED ( 233880 664610 ) S ;
-    - U9 HM_100x100_1x1 + FIXED ( 233880 232430 ) FN ;
+    - U1 HM_100x400_4x4 + FIXED ( 17880 16610 ) FS ;
+    - U10 HM_100x100_1x1 + FIXED ( 449880 16550 ) N ;
+    - U2 HM_100x100_1x1 + FIXED ( 233880 232430 ) N ;
+    - U3 HM_100x100_1x1 + FIXED ( 233880 448450 ) FS ;
+    - U4 HM_100x100_1x1 + FIXED ( 233880 664610 ) FS ;
+    - U5 HM_100x100_1x1 + FIXED ( 233880 16550 ) N ;
+    - U6 HM_100x400_4x4 + FIXED ( 665880 16610 ) FS ;
+    - U7 HM_100x100_1x1 + FIXED ( 449880 232430 ) N ;
+    - U8 HM_100x100_1x1 + FIXED ( 449880 448450 ) FS ;
+    - U9 HM_100x100_1x1 + FIXED ( 449880 664610 ) FS ;
 END COMPONENTS
 NETS 12 ;
     - w1 ( U2 I1 ) ( U1 O1 ) + USE SIGNAL ;