diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/DFAType.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/DFAType.java
index 56f84ea7b071..f5689b745652 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/DFAType.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/DFAType.java
@@ -9,7 +9,6 @@ import com.intellij.psi.util.TypeConversionUtil;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.plugins.groovy.lang.psi.controlFlow.Instruction;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.NegatingGotoInstruction;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.impl.ConditionInstruction;
 import org.jetbrains.plugins.groovy.lang.psi.impl.statements.expressions.TypesUtil;
@@ -42,7 +41,7 @@ public class DFAType {
       myNegated = negated;
     }
 
-    Mixin negate() {
+    private Mixin negate() {
       return new Mixin(ID, myType, myCondition, !myNegated);
     }
 
@@ -97,24 +96,26 @@ public class DFAType {
     return true;
   }
 
+  @Contract("-> new")
+  @NotNull
+  public DFAType copy() {
+    final DFAType type = new DFAType(primary);
+    type.mixins.addAll(mixins);
+    return type;
+  }
+
   @Contract("_ -> new")
   @NotNull
-  public DFAType negate(@NotNull Instruction instruction) {
-    final DFAType type = new DFAType(primary);
-
-    type.mixins.addAll(mixins);
-
-    for (NegatingGotoInstruction negation: instruction.getNegatingGotoInstruction()) {
-      final Set<ConditionInstruction> conditionsToNegate = negation.getCondition().getDependentConditions();
-
-      for (ListIterator<Mixin> iterator = type.mixins.listIterator(); iterator.hasNext(); ) {
-        Mixin mixin = iterator.next();
-        if (conditionsToNegate.contains(mixin.myCondition)) {
-          iterator.set(mixin.negate());
-        }
+  public DFAType negate(@NotNull NegatingGotoInstruction negation) {
+    DFAType result = copy();
+    final Set<ConditionInstruction> conditionsToNegate = negation.getCondition().getDependentConditions();
+    for (ListIterator<Mixin> iterator = result.mixins.listIterator(); iterator.hasNext(); ) {
+      Mixin mixin = iterator.next();
+      if (conditionsToNegate.contains(mixin.myCondition)) {
+        iterator.set(mixin.negate());
       }
     }
-    return type;
+    return result;
   }
 
   @Nullable
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/InferenceCache.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/InferenceCache.java
index 9dabb18af14c..a497bbf59f7a 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/InferenceCache.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/InferenceCache.java
@@ -1,4 +1,4 @@
-// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.plugins.groovy.lang.psi.dataFlow.types;
 
 import com.intellij.openapi.util.Couple;
@@ -88,8 +88,7 @@ class InferenceCache {
 
   @Nullable
   DFAType getCachedInferredType(@NotNull String variableName, @NotNull Instruction instruction) {
-    DFAType dfaType = myVarTypes.get().get(instruction.num()).getVariableType(variableName);
-    return dfaType == null ? null : dfaType.negate(instruction);
+    return myVarTypes.get().get(instruction.num()).getVariableType(variableName);
   }
 
   private Couple<Set<Instruction>> collectRequiredInstructions(@NotNull Instruction instruction,
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypeDfaInstance.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypeDfaInstance.java
index e80405a28b3c..7ebb963de60c 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypeDfaInstance.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypeDfaInstance.java
@@ -10,6 +10,7 @@ import org.jetbrains.plugins.groovy.lang.psi.api.GroovyMethodResult;
 import org.jetbrains.plugins.groovy.lang.psi.api.GroovyResolveResult;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.Instruction;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.MixinTypeInstruction;
+import org.jetbrains.plugins.groovy.lang.psi.controlFlow.NegatingGotoInstruction;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.ReadWriteVariableInstruction;
 import org.jetbrains.plugins.groovy.lang.psi.controlFlow.impl.ArgumentsInstruction;
 import org.jetbrains.plugins.groovy.lang.psi.dataFlow.DFAType;
@@ -47,6 +48,9 @@ class TypeDfaInstance implements DfaInstance<TypeDfaState> {
     else if (instruction instanceof ArgumentsInstruction) {
       handleArguments(state, (ArgumentsInstruction)instruction);
     }
+    else if (instruction instanceof NegatingGotoInstruction) {
+      handleNegation(state, (NegatingGotoInstruction)instruction);
+    }
   }
 
   private void handleMixin(@NotNull final TypeDfaState state, @NotNull final MixinTypeInstruction instruction) {
@@ -57,7 +61,7 @@ class TypeDfaInstance implements DfaInstance<TypeDfaState> {
       ReadWriteVariableInstruction originalInstr = instruction.getInstructionToMixin(myFlow);
       assert originalInstr != null && !originalInstr.isWrite();
 
-      final DFAType original = state.getOrCreateVariableType(varName).negate(originalInstr);
+      DFAType original = state.getOrCreateVariableType(varName);
       original.addMixin(instruction.inferMixinType(), instruction.getConditionInstruction());
       return original;
     });
@@ -83,7 +87,7 @@ class TypeDfaInstance implements DfaInstance<TypeDfaState> {
 
   private void handleArgument(TypeDfaState state, ArgumentsInstruction instruction, String variableName, Collection<Argument> arguments) {
     updateVariableType(state, instruction, variableName, () -> {
-      final DFAType result = state.getOrCreateVariableType(variableName).negate(instruction);
+      final DFAType result = state.getOrCreateVariableType(variableName);
       final GroovyResolveResult[] results = instruction.getElement().multiResolve(false);
       for (GroovyResolveResult variant : results) {
         if (!(variant instanceof GroovyMethodResult)) continue;
@@ -121,12 +125,18 @@ class TypeDfaInstance implements DfaInstance<TypeDfaState> {
         type = computation.compute();
       }
       else {
-        type = TypeInferenceHelper.doInference(state.getBindings(instruction), computation);
+        type = TypeInferenceHelper.doInference(state.getBindings(), computation);
       }
     }
     state.putType(variableName, type);
   }
 
+  private static void handleNegation(@NotNull TypeDfaState state, @NotNull NegatingGotoInstruction negation) {
+    for (Map.Entry<String, DFAType> entry : state.getVarTypes().entrySet()) {
+      entry.setValue(entry.getValue().negate(negation));
+    }
+  }
+
   @Override
   @NotNull
   public TypeDfaState initial() {
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypesSemilattice.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypesSemilattice.java
index bf62824e0476..b665b4ea779c 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypesSemilattice.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/dataFlow/types/TypesSemilattice.java
@@ -7,7 +7,6 @@ import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.plugins.groovy.lang.psi.controlFlow.Instruction;
 import org.jetbrains.plugins.groovy.lang.psi.dataFlow.DFAType;
 import org.jetbrains.plugins.groovy.lang.psi.dataFlow.Semilattice;
 
@@ -54,6 +53,10 @@ class TypeDfaState {
     myVarTypes = ContainerUtil.newHashMap(another.myVarTypes);
   }
 
+  Map<String, DFAType> getVarTypes() {
+    return myVarTypes;
+  }
+
   TypeDfaState mergeWith(TypeDfaState another) {
     if (another.myVarTypes.isEmpty()) {
       return this;
@@ -92,14 +95,14 @@ class TypeDfaState {
   @NotNull
   DFAType getOrCreateVariableType(String variableName) {
     DFAType result = getVariableType(variableName);
-    return result == null ? DFAType.create(null) : result;
+    return result == null ? DFAType.create(null) : result.copy();
   }
 
-  Map<String, PsiType> getBindings(Instruction instruction) {
-    HashMap<String,PsiType> map = ContainerUtil.newHashMap();
+  Map<String, PsiType> getBindings() {
+    HashMap<String, PsiType> map = ContainerUtil.newHashMap();
     for (Map.Entry<String, DFAType> entry : myVarTypes.entrySet()) {
       DFAType value = entry.getValue();
-      map.put(entry.getKey(), value == null ? null : value.negate(instruction).getResultType());
+      map.put(entry.getKey(), value == null ? null : value.getResultType());
     }
     return map;
   }