diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/BranchedValue.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/BranchedValue.kt
index 7eb32875fc1..a40ab234b95 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/BranchedValue.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/BranchedValue.kt
@@ -101,9 +101,6 @@ open class BranchedValue(val arg1: StackValue, val arg2: StackValue? = null, val
         }
 
         fun createInvertValue(argument: StackValue): StackValue {
-            if (argument.type != Type.BOOLEAN_TYPE) {
-                throw UnsupportedOperationException("operand of ! must be boolean")
-            }
             return Invert(condJump(argument))
         }
 
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/ExpressionCodegen.java b/compiler/backend/src/org/jetbrains/kotlin/codegen/ExpressionCodegen.java
index 7d967cceb94..23622cf4abe 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/ExpressionCodegen.java
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/ExpressionCodegen.java
@@ -3051,11 +3051,11 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
     }
 
     private StackValue generateBooleanAnd(JetBinaryExpression expression) {
-        return StackValue.and(genLazy(expression.getLeft(), Type.BOOLEAN_TYPE), genLazy(expression.getRight(), Type.BOOLEAN_TYPE));
+        return StackValue.and(gen(expression.getLeft()), gen(expression.getRight()));
     }
 
     private StackValue generateBooleanOr(JetBinaryExpression expression) {
-        return StackValue.or(genLazy(expression.getLeft(), Type.BOOLEAN_TYPE), genLazy(expression.getRight(), Type.BOOLEAN_TYPE));
+        return StackValue.or(gen(expression.getLeft()), gen(expression.getRight()));
     }
 
     private StackValue generateEquals(JetExpression left, JetExpression right, IElementType opToken) {
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/Not.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/Not.kt
index b72a508cb3c..3886864170a 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/Not.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/Not.kt
@@ -28,17 +28,6 @@ import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.org.objectweb.asm.Type
 
 public class Not : IntrinsicMethod() {
-    fun generateImpl(codegen: ExpressionCodegen, returnType: Type, element: PsiElement?, arguments: List<JetExpression>, receiver: StackValue): StackValue {
-        val stackValue: StackValue
-        if (arguments.size() == 1) {
-            stackValue = codegen.gen(arguments.get(0))
-        }
-        else {
-            stackValue = receiver
-        }
-        return StackValue.not(StackValue.coercion(stackValue, Type.BOOLEAN_TYPE))
-    }
-
     override fun toCallable(method: CallableMethod): Callable {
         return object : IntrinsicCallable(method) {
             override fun invokeMethodWithArguments(resolvedCall: ResolvedCall<*>, receiver: StackValue, codegen: ExpressionCodegen): StackValue {
@@ -50,7 +39,7 @@ public class Not : IntrinsicMethod() {
                         else {
                             StackValue.receiver(resolvedCall, receiver, codegen, this)
                         }
-                return StackValue.not(StackValue.coercion(stackValue, Type.BOOLEAN_TYPE))
+                return StackValue.not(stackValue)
             }
         }
     }