diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeOperatorLowering.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeOperatorLowering.kt
index 10fa6c91c5a..6b7c69ddab9 100644
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeOperatorLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeOperatorLowering.kt
@@ -17,7 +17,9 @@ import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
@@ -139,8 +141,13 @@ private class TypeOperatorLowering(private val context: JvmBackendContext) : Fil
                 irNot(lowerInstanceOf(expression.argument.transformVoid(), expression.typeOperand))
 
             IrTypeOperator.IMPLICIT_NOTNULL -> {
-                val (startOffset, endOffset) = expression.extents()
-                val source = sourceViewFor(parent as IrDeclaration).subSequence(startOffset, endOffset).toString()
+                val owner = scope.scopeOwnerSymbol.owner
+                val source = if (owner is IrFunction && owner.origin == IrDeclarationOrigin.DELEGATED_MEMBER) {
+                    "${owner.name.asString()}(...)"
+                } else {
+                    val (startOffset, endOffset) = expression.extents()
+                    sourceViewFor(parent as IrDeclaration).subSequence(startOffset, endOffset).toString()
+                }
 
                 irLetS(expression.argument.transformVoid(), irType = context.irBuiltIns.anyNType) { valueSymbol ->
                     irComposite(resultType = expression.type) {
diff --git a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ClassGenerator.kt b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ClassGenerator.kt
index 4edee3f4d9a..c64c4023ed8 100644
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ClassGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ClassGenerator.kt
@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.psi2ir.generators
 import org.jetbrains.kotlin.backend.common.CodegenUtil
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.descriptors.IrImplementingDelegateDescriptorImpl
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
@@ -305,7 +306,7 @@ class ClassGenerator(
         delegateToDescriptor: FunctionDescriptor
     ): IrSimpleFunction =
         context.symbolTable.declareSimpleFunctionWithOverrides(
-            irDelegate.startOffset, irDelegate.endOffset,
+            UNDEFINED_OFFSET, UNDEFINED_OFFSET,
             IrDeclarationOrigin.DELEGATED_MEMBER,
             delegatedDescriptor
         ).buildWithScope { irFunction ->
@@ -323,8 +324,8 @@ class ClassGenerator(
         delegateToDescriptor: FunctionDescriptor,
         irDelegatedFunction: IrSimpleFunction
     ): IrBlockBody {
-        val startOffset = irDelegate.startOffset
-        val endOffset = irDelegate.endOffset
+        val startOffset = UNDEFINED_OFFSET
+        val endOffset = UNDEFINED_OFFSET
 
         val irBlockBody = context.irFactory.createBlockBody(startOffset, endOffset)
 
diff --git a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/accidentalOverrides/delegatedFunctionOverriddenByProperty_ir.kt b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/accidentalOverrides/delegatedFunctionOverriddenByProperty_ir.kt
index 6102ff4cb74..3bb7b70c3c3 100644
--- a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/accidentalOverrides/delegatedFunctionOverriddenByProperty_ir.kt
+++ b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/accidentalOverrides/delegatedFunctionOverriddenByProperty_ir.kt
@@ -7,4 +7,4 @@ interface D {
     val x: Int
 }
 
-class C(d: D) : D by <!ACCIDENTAL_OVERRIDE!>d<!>, B
\ No newline at end of file
+class <!ACCIDENTAL_OVERRIDE!>C(d: D)<!> : D by d, B
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegateToTwoTraits_ir.kt b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegateToTwoTraits_ir.kt
index cf48fc934c0..6912654a04b 100644
--- a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegateToTwoTraits_ir.kt
+++ b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegateToTwoTraits_ir.kt
@@ -9,7 +9,7 @@ interface Bar<T> {
     fun foo(l: List<T>)
 }
 
-class Baz(f: Foo<String>, b: Bar<Int>) :
-    Foo<String> by <!CONFLICTING_JVM_DECLARATIONS!>f<!>,
-    Bar<Int> by <!CONFLICTING_JVM_DECLARATIONS!>b<!> {
+class <!CONFLICTING_JVM_DECLARATIONS!>Baz(f: Foo<String>, b: Bar<Int>)<!> :
+    Foo<String> by f,
+    Bar<Int> by b {
 }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationAndOwnMethod_ir.kt b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationAndOwnMethod_ir.kt
index 0fa4c2bb896..5fac2b426fe 100644
--- a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationAndOwnMethod_ir.kt
+++ b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationAndOwnMethod_ir.kt
@@ -5,6 +5,6 @@ interface Foo<T> {
     fun foo(l: List<T>)
 }
 
-class Bar(f: Foo<String>): Foo<String> by <!CONFLICTING_JVM_DECLARATIONS!>f<!> {
+class <!CONFLICTING_JVM_DECLARATIONS!>Bar(f: Foo<String>)<!>: Foo<String> by f {
     <!CONFLICTING_JVM_DECLARATIONS!>fun foo(l: List<Int>)<!> {}
 }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationToTraitImplAndOwnMethod_ir.kt b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationToTraitImplAndOwnMethod_ir.kt
index 94ad1c9da35..9757a6ff8b8 100644
--- a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationToTraitImplAndOwnMethod_ir.kt
+++ b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/delegationToTraitImplAndOwnMethod_ir.kt
@@ -7,7 +7,7 @@ interface Foo<T> {
     }
 }
 
-class Bar(f: Foo<String>): Foo<String> by <!CONFLICTING_JVM_DECLARATIONS!>f<!> {
+class <!CONFLICTING_JVM_DECLARATIONS!>Bar(f: Foo<String>)<!>: Foo<String> by f {
     <!CONFLICTING_JVM_DECLARATIONS!>fun foo(l: List<Int>)<!> {}
 }
 
diff --git a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/superTraitAndDelegationToTraitImpl_ir.kt b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/superTraitAndDelegationToTraitImpl_ir.kt
index 21e42f83e13..8bb10a9d25f 100644
--- a/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/superTraitAndDelegationToTraitImpl_ir.kt
+++ b/compiler/testData/diagnostics/testsWithJvmBackend/duplicateJvmSignature/erasure/superTraitAndDelegationToTraitImpl_ir.kt
@@ -9,6 +9,6 @@ interface B {
     fun foo(l: List<Int>) {}
 }
 
-class C(f: A<String>): A<String> by <!ACCIDENTAL_OVERRIDE!>f<!>, B
+class <!ACCIDENTAL_OVERRIDE!>C(f: A<String>)<!>: A<String> by f, B
 
 <!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>class D<!>(f: A<Int>): A<Int> by f, B
\ No newline at end of file
diff --git a/idea/jvm-debugger/jvm-debugger-test/testData/stepping/custom/smartStepIntoWithDelegates.out b/idea/jvm-debugger/jvm-debugger-test/testData/stepping/custom/smartStepIntoWithDelegates.out
index c07cd295ce5..67a684b8be3 100644
--- a/idea/jvm-debugger/jvm-debugger-test/testData/stepping/custom/smartStepIntoWithDelegates.out
+++ b/idea/jvm-debugger/jvm-debugger-test/testData/stepping/custom/smartStepIntoWithDelegates.out
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 LineBreakpoint created at smartStepIntoWithDelegates.kt:24
 LineBreakpoint created at smartStepIntoWithDelegates.kt:32
 LineBreakpoint created at smartStepIntoWithDelegates.kt:40