diff --git a/teavm-core/src/main/java/org/teavm/javascript/Decompiler.java b/teavm-core/src/main/java/org/teavm/javascript/Decompiler.java
index 33d3c3311..59845bef8 100644
--- a/teavm-core/src/main/java/org/teavm/javascript/Decompiler.java
+++ b/teavm-core/src/main/java/org/teavm/javascript/Decompiler.java
@@ -219,7 +219,7 @@ public class Decompiler {
             node.getVariables().add(program.variableAt(i).getRegister());
         }
         Optimizer optimizer = new Optimizer();
-        optimizer.optimize(node, program, splitter);
+        optimizer.optimize(node, splitter);
         node.getModifiers().addAll(mapModifiers(method.getModifiers()));
         int paramCount = Math.min(method.getSignature().length, program.variableCount());
         for (int i = 0; i < paramCount; ++i) {
diff --git a/teavm-core/src/main/java/org/teavm/javascript/Optimizer.java b/teavm-core/src/main/java/org/teavm/javascript/Optimizer.java
index f69803a48..8b33e82a7 100644
--- a/teavm-core/src/main/java/org/teavm/javascript/Optimizer.java
+++ b/teavm-core/src/main/java/org/teavm/javascript/Optimizer.java
@@ -43,10 +43,10 @@ public class Optimizer {
         }
     }
 
-    public void optimize(AsyncMethodNode method, Program program, AsyncProgramSplitter splitter) {
+    public void optimize(AsyncMethodNode method, AsyncProgramSplitter splitter) {
         ReadWriteStatsBuilder stats = new ReadWriteStatsBuilder(method.getVariables().size());
-        stats.analyze(program);
         for (int i = 0; i < splitter.size(); ++i) {
+            stats.analyze(splitter.getProgram(i));
             Integer var = splitter.getInput(i);
             if (var != null) {
                 stats.reads[var]++;