Removed useless as casts from compiler code

It allows compiling code with K2 and enabled `-Werror`

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/descriptors/ClassLayoutBuilder.kt

@@ -7,23 +7,24 @@ package org.jetbrains.kotlin.backend.konan.descriptors
 
 import llvm.LLVMABIAlignmentOfType
 import llvm.LLVMABISizeOfType
-import llvm.LLVMPreferredAlignmentOfType
 import llvm.LLVMStoreSizeOfType
 import org.jetbrains.kotlin.backend.common.lower.coroutines.getOrCreateFunctionWithContinuationStub
 import org.jetbrains.kotlin.backend.konan.*
-import org.jetbrains.kotlin.backend.konan.ir.*
+import org.jetbrains.kotlin.backend.konan.ir.getSuperClassNotAny
+import org.jetbrains.kotlin.backend.konan.ir.isSpecialClassWithNoSupertypes
 import org.jetbrains.kotlin.backend.konan.llvm.CodegenLlvmHelpers
 import org.jetbrains.kotlin.backend.konan.llvm.computeFunctionName
-import org.jetbrains.kotlin.backend.konan.llvm.toLLVMType
 import org.jetbrains.kotlin.backend.konan.llvm.localHash
+import org.jetbrains.kotlin.backend.konan.llvm.toLLVMType
 import org.jetbrains.kotlin.backend.konan.lower.bridgeTarget
-import org.jetbrains.kotlin.backend.konan.serialization.KonanIrLinker
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrClassReference
 import org.jetbrains.kotlin.ir.expressions.IrConst
-import org.jetbrains.kotlin.ir.objcinterop.*
+import org.jetbrains.kotlin.ir.objcinterop.canObjCClassMethodBeCalledVirtually
+import org.jetbrains.kotlin.ir.objcinterop.isKotlinObjCClass
+import org.jetbrains.kotlin.ir.objcinterop.isObjCClassMethod
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.*
@@ -470,8 +471,7 @@ internal class ClassLayoutBuilder(val irClass: IrClass, val context: Context) {
         irClass.annotations.forEach {
             val irFile = irClass.fileOrNull
 
-            val annotationClass = (it.symbol.owner as? IrConstructor)?.constructedClass
-                    ?: error(irFile, it, "unexpected annotation")
+            val annotationClass = it.symbol.owner.constructedClass
 
             if (annotationClass.hasAnnotation(RuntimeNames.associatedObjectKey)) {
                 val argument = it.getValueArgument(0)

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/InteropLowering.kt

@@ -51,8 +51,6 @@ import org.jetbrains.kotlin.konan.library.KonanLibrary
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.native.interop.ObjCMethodInfo
-import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
-import org.jetbrains.kotlin.resolve.descriptorUtil.module
 
 internal class InteropLowering(generationState: NativeGenerationState) : FileLoweringPass {
     // TODO: merge these lowerings.
@@ -1034,11 +1032,7 @@ private class InteropTransformer(
         if (!function.isFromInteropLibrary()) return null
         if (!function.isGetter) return null
 
-        val constantProperty = (function as? IrSimpleFunction)
-                ?.correspondingPropertySymbol
-                ?.owner
-                ?.takeIf { it.isConst }
-                ?: return null
+        val constantProperty = function.correspondingPropertySymbol?.owner?.takeIf { it.isConst } ?: return null
 
         val initializer = constantProperty.backingField?.initializer?.expression
         require(initializer is IrConst<*>) { renderCompilerError(expression) }
@@ -1088,9 +1082,7 @@ private class InteropTransformer(
         builder.at(expression)
         val function = expression.symbol.owner
 
-        if ((function as? IrSimpleFunction)?.resolveFakeOverrideMaybeAbstract()?.symbol
-                == symbols.interopNativePointedRawPtrGetter) {
-
+        if (function.resolveFakeOverrideMaybeAbstract()?.symbol == symbols.interopNativePointedRawPtrGetter) {
             // Replace by the intrinsic call to be handled by code generator:
             return builder.irCall(symbols.interopNativePointedGetRawPointer).apply {
                 extensionReceiver = expression.dispatchReceiver

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/ObjectClassLowering.kt

@@ -23,7 +23,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.objcinterop.*
 import org.jetbrains.kotlin.ir.util.*
-import org.jetbrains.kotlin.ir.util.irCall
 
 internal fun Context.getObjectClassInstanceFunction(clazz: IrClass) = mapping.objectInstanceGetter.getOrPut(clazz) {
     when {
@@ -159,8 +158,7 @@ internal class ObjectClassLowering(val generationState: NativeGenerationState) :
         val statements = this.body?.statements ?: return false
         if (statements.isEmpty()) return false
         val constructorCall = statements[0] as? IrDelegatingConstructorCall ?: return false
-        val constructor = constructorCall.symbol.owner as? IrConstructor ?: return false
-        if (!constructor.constructedClass.isAny()) return false
+        if (!constructorCall.symbol.owner.constructedClass.isAny()) return false
         return statements.asSequence().drop(1).all {
             it is IrBlock && it.origin == IrStatementOrigin.INITIALIZE_FIELD
         }

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/PostInlineLowering.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.backend.konan.lower
 
 import org.jetbrains.kotlin.backend.common.BodyLoweringPass
-import org.jetbrains.kotlin.backend.common.ir.Symbols
 import org.jetbrains.kotlin.backend.common.lower.at
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
 import org.jetbrains.kotlin.backend.konan.Context
@@ -83,7 +82,7 @@ internal class PostInlineLowering(val context: Context) : BodyLoweringPass {
                     val builder = StringBuilder()
                     args.elements.forEach {
                         require(it is IrConst<*>) { renderCompilerError(irFile, it, "expected const") }
-                        val value = (it as? IrConst<*>)?.value
+                        val value = it.value
                         require(value is Short && value >= 0 && value <= 0xff) {
                             renderCompilerError(irFile, it, "incorrect value for binary data: $value")
                         }