JVM_IR. Accessor lowering

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/IrUtils.kt

@@ -16,7 +16,11 @@ import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
 import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.symbols.*
+import org.jetbrains.kotlin.ir.symbols.impl.IrTypeParameterSymbolImpl
+import org.jetbrains.kotlin.ir.symbols.impl.IrValueParameterSymbolImpl
 import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
+import org.jetbrains.kotlin.ir.types.impl.makeTypeProjection
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.psiUtil.endOffset
@@ -322,6 +326,16 @@ fun IrSimpleFunction.resolveFakeOverride(): IrSimpleFunction? {
     return realOverrides.singleOrNull { it.modality != Modality.ABSTRACT }
 }
 
+fun IrField.resolveFakeOverride(): IrField? {
+    var toVisit = setOf(this)
+    val nonOverridden = mutableSetOf<IrField>()
+    while (toVisit.isNotEmpty()) {
+        nonOverridden += toVisit.filter { it.overriddenSymbols.isEmpty() }
+        toVisit = toVisit.flatMap { it.overriddenSymbols }.map { it.owner }.toSet()
+    }
+    return nonOverridden.singleOrNull()
+}
+
 val IrClass.isAnnotationClass get() = kind == ClassKind.ANNOTATION_CLASS
 val IrClass.isEnumClass get() = kind == ClassKind.ENUM_CLASS
 val IrClass.isEnumEntry get() = kind == ClassKind.ENUM_ENTRY
@@ -442,6 +456,12 @@ fun IrFunction.createDispatchReceiverParameter() {
     ).also { it.parent = this }
 }
 
+// In presence of `IrBlock`s, return the expression that actually serves as the value (the last one).
+tailrec fun IrExpression.removeBlocks(): IrExpression? = when (this) {
+    is IrBlock -> (statements.last() as? IrExpression)?.removeBlocks()
+    else -> this
+}
+
 fun ReferenceSymbolTable.referenceClassifier(classifier: ClassifierDescriptor): IrClassifierSymbol =
     when (classifier) {
         is TypeParameterDescriptor ->