diff --git a/jadx-core/src/main/java/jadx/api/JadxDecompiler.java b/jadx-core/src/main/java/jadx/api/JadxDecompiler.java
index 5382b02e0..b16481e8d 100644
--- a/jadx-core/src/main/java/jadx/api/JadxDecompiler.java
+++ b/jadx-core/src/main/java/jadx/api/JadxDecompiler.java
@@ -66,9 +66,9 @@ public final class JadxDecompiler {
 
 	private BinaryXMLParser xmlParser;
 
-	private Map<ClassNode, JavaClass> classesMap = new HashMap<ClassNode, JavaClass>();
-	private Map<MethodNode, JavaMethod> methodsMap = new HashMap<MethodNode, JavaMethod>();
-	private Map<FieldNode, JavaField> fieldsMap = new HashMap<FieldNode, JavaField>();
+	private Map<ClassNode, JavaClass> classesMap = new java.util.concurrent.ConcurrentHashMap<ClassNode, JavaClass>();
+	private Map<MethodNode, JavaMethod> methodsMap = new java.util.concurrent.ConcurrentHashMap<MethodNode, JavaMethod>();
+	private Map<FieldNode, JavaField> fieldsMap = new java.util.concurrent.ConcurrentHashMap<FieldNode, JavaField>();
 
 	public JadxDecompiler() {
 		this(new JadxArgs());
diff --git a/jadx-core/src/main/java/jadx/core/clsp/ClspGraph.java b/jadx-core/src/main/java/jadx/core/clsp/ClspGraph.java
index 2f78059c8..674250fde 100644
--- a/jadx-core/src/main/java/jadx/core/clsp/ClspGraph.java
+++ b/jadx-core/src/main/java/jadx/core/clsp/ClspGraph.java
@@ -23,7 +23,7 @@ import org.slf4j.LoggerFactory;
 public class ClspGraph {
 	private static final Logger LOG = LoggerFactory.getLogger(ClspGraph.class);
 
-	private final Map<String, Set<String>> ancestorCache = new WeakHashMap<String, Set<String>>();
+	private final Map<String, Set<String>> ancestorCache = Collections.synchronizedMap(new WeakHashMap<String, Set<String>>());
 	private Map<String, NClass> nameMap;
 
 	private final Set<String> missingClasses = new HashSet<String>();
diff --git a/jadx-core/src/main/java/jadx/core/utils/BlockUtils.java b/jadx-core/src/main/java/jadx/core/utils/BlockUtils.java
index aecd7d51d..d5b5bafa8 100644
--- a/jadx-core/src/main/java/jadx/core/utils/BlockUtils.java
+++ b/jadx-core/src/main/java/jadx/core/utils/BlockUtils.java
@@ -453,15 +453,18 @@ public class BlockUtils {
 	 */
 	public static List<BlockNode> collectBlocksDominatedBy(BlockNode dominator, BlockNode start) {
 		List<BlockNode> result = new ArrayList<BlockNode>();
-		collectWhileDominates(dominator, start, result);
+		HashSet<BlockNode> visited = new HashSet<BlockNode>();
+		collectWhileDominates(dominator, start, result, visited);
 		return result;
 	}
 
-	private static void collectWhileDominates(BlockNode dominator, BlockNode child, List<BlockNode> result) {
+	private static void collectWhileDominates(BlockNode dominator, BlockNode child, List<BlockNode> result, HashSet<BlockNode> visited) {
+		if (visited.contains(child)) return;
+		visited.add(child);
 		for (BlockNode node : child.getCleanSuccessors()) {
 			if (node.isDominator(dominator)) {
 				result.add(node);
-				collectWhileDominates(dominator, node, result);
+				collectWhileDominates(dominator, node, result, visited);
 			}
 		}
 	}