diff --git a/teavm-core/src/main/java/org/teavm/common/GraphUtils.java b/teavm-core/src/main/java/org/teavm/common/GraphUtils.java
index ea78e32dc..d9a8d55fb 100644
--- a/teavm-core/src/main/java/org/teavm/common/GraphUtils.java
+++ b/teavm-core/src/main/java/org/teavm/common/GraphUtils.java
@@ -114,45 +114,51 @@ public final class GraphUtils {
         int[] headerIndex = new int[graph.size()];
         int lastIndex = 0;
         IntegerStack stack = new IntegerStack(graph.size());
+
         for (int startNode : start) {
             stack.push(startNode);
-        }
-
-        IntegerArray currentComponent = new IntegerArray(1);
-        while (!stack.isEmpty()) {
-            int node = stack.pop();
-            if (visitIndex[node] > 0) {
-                if (headerIndex[node] > 0) {
-                    continue;
-                }
-                currentComponent.add(node);
-                int hdr = visitIndex[node];
-                for (int successor : graph.outgoingEdges(node)) {
-                    if (!filter.match(successor)) {
+            IntegerArray currentComponent = new IntegerArray(1);
+            while (!stack.isEmpty()) {
+                int node = stack.pop();
+                if (visitIndex[node] > 0) {
+                    if (headerIndex[node] > 0) {
                         continue;
                     }
-                    if (headerIndex[successor] == 0) {
-                        hdr = Math.min(hdr, visitIndex[successor]);
-                    } else {
-                        hdr = Math.min(hdr, headerIndex[successor]);
+                    currentComponent.add(node);
+                    int hdr = visitIndex[node];
+                    for (int successor : graph.outgoingEdges(node)) {
+                        if (!filter.match(successor)) {
+                            continue;
+                        }
+                        if (headerIndex[successor] == 0) {
+                            hdr = Math.min(hdr, visitIndex[successor]);
+                        } else {
+                            hdr = Math.min(hdr, headerIndex[successor]);
+                        }
+                    }
+                    if (hdr == visitIndex[node]) {
+                        components.add(currentComponent.getAll());
+                        currentComponent.clear();
+                    }
+                    headerIndex[node] = hdr;
+                } else {
+                    visitIndex[node] = ++lastIndex;
+                    stack.push(node);
+                    for (int successor : graph.outgoingEdges(node)) {
+                        if (!filter.match(successor) || visitIndex[successor] > 0) {
+                            continue;
+                        }
+                        stack.push(successor);
                     }
                 }
-                if (hdr == visitIndex[node]) {
-                    components.add(currentComponent.getAll());
-                    currentComponent.clear();
-                }
-                headerIndex[node] = hdr;
-            } else {
-                visitIndex[node] = ++lastIndex;
-                stack.push(node);
-                for (int successor : graph.outgoingEdges(node)) {
-                    if (!filter.match(successor) || visitIndex[successor] > 0) {
-                        continue;
-                    }
-                    stack.push(successor);
+            }
+            for (int i = 0; i < headerIndex.length; ++i) {
+                if (visitIndex[i] > 0) {
+                    headerIndex[i] = graph.size() + 1;
                 }
             }
         }
+
         return components.toArray(new int[0][]);
     }
 
diff --git a/teavm-core/src/main/java/org/teavm/common/irreducible/IrreducibleGraphConverter.java b/teavm-core/src/main/java/org/teavm/common/irreducible/IrreducibleGraphConverter.java
index 68d2cd91b..b5e06125b 100644
--- a/teavm-core/src/main/java/org/teavm/common/irreducible/IrreducibleGraphConverter.java
+++ b/teavm-core/src/main/java/org/teavm/common/irreducible/IrreducibleGraphConverter.java
@@ -81,22 +81,6 @@ public class IrreducibleGraphConverter {
         }
     }
 
-    private int[] reachUnder(DJGraph djGraph, int back, int header) {
-        IntSet naturalLoop = IntOpenHashSet.from(header);
-        IntegerStack stack = new IntegerStack(djGraph.getGraph().size());
-        stack.push(back);
-        while (!stack.isEmpty()) {
-            int node = stack.pop();
-            if (!naturalLoop.add(node)) {
-                continue;
-            }
-            for (int pred : djGraph.getGraph().incomingEdges(node)) {
-                stack.push(pred);
-            }
-        }
-        return naturalLoop.toArray();
-    }
-
     private void handleStronglyConnectedComponent(DJGraph djGraph, int[] scc, int[][] nodeMap) {
         // Find shared dominator
         int sharedDom = scc[0];
@@ -104,6 +88,13 @@ public class IrreducibleGraphConverter {
             sharedDom = djGraph.getDomTree().commonDominatorOf(sharedDom, scc[i]);
         }
 
+        for (int i = 0; i < scc.length; ++i) {
+            if (scc[i] == sharedDom) {
+                djGraph.collapse(scc);
+                return;
+            }
+        }
+
         // Partition SCC into domains
         DisjointSet partitions = new DisjointSet();
         int[] sccBack = new int[djGraph.getGraph().size()];
@@ -154,7 +145,9 @@ public class IrreducibleGraphConverter {
         splitStronglyConnectedComponent(djGraph, domainNodes, sharedDom, scc, nodeMap);
 
         // Collapse
-        djGraph.collapse(scc);
+        int[] sccAndTop = Arrays.copyOf(scc, scc.length + 1);
+        sccAndTop[scc.length] = sharedDom;
+        djGraph.collapse(sccAndTop);
     }
 
     private void splitStronglyConnectedComponent(DJGraph djGraph, IntSet domain, int sharedDom,