diff --git a/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java b/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
index 454d12b06..1a096511f 100644
--- a/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
+++ b/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
@@ -395,7 +395,7 @@ public class ExceptionHandlingShadowStackContributor {
                     if (outgoingVariablesToRemove.contains(incoming.getValue().getIndex())) {
                         phi.getIncomings().remove(i--);
                         break;
-                    } else if (incoming.getValue().getIndex() == value) {
+                    } else if (incoming.getValue().getIndex() == value && incoming.getSource() != newBlock) {
                         if (variablesDefinedHere.contains(value)) {
                             incoming.setSource(newBlock);
                         } else {
diff --git a/core/src/main/java/org/teavm/model/util/BasicBlockSplitter.java b/core/src/main/java/org/teavm/model/util/BasicBlockSplitter.java
index d03cde370..829a39c54 100644
--- a/core/src/main/java/org/teavm/model/util/BasicBlockSplitter.java
+++ b/core/src/main/java/org/teavm/model/util/BasicBlockSplitter.java
@@ -144,7 +144,7 @@ public class BasicBlockSplitter {
 
         DefinitionExtractor defExtractor = new DefinitionExtractor();
         for (BasicBlock block : sourceParts) {
-            if (block != null) {
+            if (block != source) {
                 for (Map.Entry<Phi, Variable> lastDefinedEntry : lastDefinedValues.entrySet()) {
                     Incoming incomingCopy = new Incoming();
                     incomingCopy.setSource(block);