diff --git a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt
index 67ec0092e50..d73998a3b67 100644
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt
@@ -21,10 +21,7 @@ import org.jetbrains.kotlin.backend.common.ir.SharedVariablesManager
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrFactory
-import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
-import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
-import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.name.FqName
 
 interface BackendContext {
@@ -33,8 +30,6 @@ interface BackendContext {
     val irBuiltIns: IrBuiltIns
     val sharedVariablesManager: SharedVariablesManager
     val internalPackageFqn: FqName
-    val transformedFunction: MutableMap<IrFunctionSymbol, IrSimpleFunctionSymbol>
-    val lateinitNullableFields: MutableMap<IrField, IrField>
     val extractedLocalClasses: MutableSet<IrClass>
     val irFactory: IrFactory
 }
diff --git a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt
index 1a69d6935fd..33e68f4ab6e 100644
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt
@@ -45,12 +45,6 @@ class JsIrBackendContext(
     override val scriptMode: Boolean = false,
     override val es6mode: Boolean = false
 ) : JsCommonBackendContext {
-    override val transformedFunction
-        get() = error("Use Mapping.inlineClassMemberToStatic instead")
-
-    override val lateinitNullableFields
-        get() = error("Use Mapping.lateInitFieldToNullableField instead")
-
     override val extractedLocalClasses: MutableSet<IrClass> = hashSetOf()
 
     override val builtIns = module.builtIns
diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt
index 4fe1b149a87..712701eabee 100644
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt
@@ -59,15 +59,11 @@ class JvmBackendContext(
     val classNameOverride: MutableMap<IrClass, JvmClassName>
         get() = generatorExtensions.classNameOverride
 
-    override val transformedFunction: MutableMap<IrFunctionSymbol, IrSimpleFunctionSymbol>
-        get() = TODO("not implemented")
-
     override val extractedLocalClasses: MutableSet<IrClass> = hashSetOf()
 
     override val irFactory: IrFactory = IrFactoryImpl
 
     override val scriptMode: Boolean = false
-    override val lateinitNullableFields = mutableMapOf<IrField, IrField>()
 
     override val builtIns = state.module.builtIns
     val typeMapper = IrTypeMapper(this)
diff --git a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt
index 22cbe8649e7..c69f3afc285 100644
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt
@@ -12,28 +12,21 @@ import org.jetbrains.kotlin.backend.wasm.lower.WasmSharedVariablesManager
 import org.jetbrains.kotlin.backend.wasm.utils.WasmInlineClassesUtils
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
-import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
 import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.SourceManager
 import org.jetbrains.kotlin.ir.SourceRangeInfo
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.backend.js.JsCommonBackendContext
 import org.jetbrains.kotlin.ir.backend.js.JsMapping
-import org.jetbrains.kotlin.ir.backend.js.JsSharedVariablesManager
 import org.jetbrains.kotlin.ir.backend.js.lower.JsInnerClassesSupport
-import org.jetbrains.kotlin.ir.builders.declarations.addFunction
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
-import org.jetbrains.kotlin.ir.declarations.persistent.PersistentIrFactory
 import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
+import org.jetbrains.kotlin.ir.declarations.persistent.PersistentIrFactory
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
-import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
-import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.DescriptorlessExternalPackageFragmentSymbol
-import org.jetbrains.kotlin.ir.util.IdSignature
 import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
@@ -49,8 +42,6 @@ class WasmBackendContext(
     override val builtIns = module.builtIns
     override var inVerbosePhase: Boolean = false
     override val scriptMode = false
-    override val transformedFunction = mutableMapOf<IrFunctionSymbol, IrSimpleFunctionSymbol>()
-    override val lateinitNullableFields = mutableMapOf<IrField, IrField>()
     override val extractedLocalClasses: MutableSet<IrClass> = hashSetOf()
     override val irFactory: IrFactory = PersistentIrFactory