Implemented 'lateinit' properties

If property is lateinit, then on each access we need to test its value
and throw UninitializedPropertyAccessException if it is null.

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt

@@ -48,6 +48,9 @@ internal class KonanLower(val context: Context) {
             DefaultArgumentStubGenerator(context).runOnFilePostfix(irFile)
             DefaultParameterInjector(context).runOnFilePostfix(irFile)
         }
+        phaser.phase(KonanPhase.LOWER_LATEINIT) {
+            LateinitLowering(context).lower(irFile)
+        }
         phaser.phase(KonanPhase.LOWER_BUILTIN_OPERATORS) {
             BuiltinOperatorLowering(context).runOnFilePostfix(irFile)
         }

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt

@@ -3,7 +3,7 @@ package org.jetbrains.kotlin.backend.konan
 import org.jetbrains.kotlin.backend.konan.util.*
 
 enum class KonanPhase(val description: String,
-                      val prerequisite: Set<KonanPhase> = setOf<KonanPhase>(),
+                      vararg prerequisite: KonanPhase,
                       var enabled: Boolean = true, var verbose: Boolean = false) {
 
     /* */ FRONTEND("Frontend builds AST"),
@@ -14,27 +14,29 @@ enum class KonanPhase(val description: String,
     /* ... ... */ LOWER_INTEROP("Interop lowering"),
     /* ... ... */ LOWER_ENUMS("Enum classes lowering"),
     /* ... ... */ LOWER_DELEGATION("Delegation lowering"),
-    /* ... ... */ LOWER_INITIALIZERS("Initializers lowering", setOf(LOWER_ENUMS)),
-    /* ... ... */ LOWER_SHARED_VARIABLES("Shared Variable Lowering", setOf(LOWER_INITIALIZERS)),
-    /* ... ... */ LOWER_CALLABLES("Callable references Lowering", setOf(
-                        LOWER_INTEROP, LOWER_INITIALIZERS, LOWER_DELEGATION)),
-    /* ... ... */ LOWER_VARARG("Vararg lowering", setOf(LOWER_CALLABLES)),
-    /* ... ... */ LOWER_LOCAL_FUNCTIONS("Local Function Lowering", setOf(LOWER_SHARED_VARIABLES)),
-    /* ... ... */ LOWER_TAILREC("tailrec lowering", setOf(LOWER_LOCAL_FUNCTIONS)),
-    /* ... ... */ LOWER_DEFAULT_PARAMETER_EXTENT("Default Parameter Extent Lowering", setOf(
-                        LOWER_TAILREC, LOWER_ENUMS)),
-    /* ... ... */ LOWER_INNER_CLASSES("Inner classes lowering", setOf(LOWER_DEFAULT_PARAMETER_EXTENT)),
-    /* ... ... */ LOWER_BUILTIN_OPERATORS("BuiltIn Operators Lowering", setOf(
-                        LOWER_DEFAULT_PARAMETER_EXTENT)),
+    /* ... ... */ LOWER_INITIALIZERS("Initializers lowering", LOWER_ENUMS),
+    /* ... ... */ LOWER_SHARED_VARIABLES("Shared Variable Lowering", LOWER_INITIALIZERS),
+    /* ... ... */ LOWER_CALLABLES("Callable references Lowering",
+                        LOWER_INTEROP, LOWER_INITIALIZERS, LOWER_DELEGATION),
+    /* ... ... */ LOWER_VARARG("Vararg lowering", LOWER_CALLABLES),
+    /* ... ... */ LOWER_LOCAL_FUNCTIONS("Local Function Lowering", LOWER_SHARED_VARIABLES),
+    /* ... ... */ LOWER_TAILREC("tailrec lowering", LOWER_LOCAL_FUNCTIONS),
+    /* ... ... */ LOWER_DEFAULT_PARAMETER_EXTENT("Default Parameter Extent Lowering",
+                        LOWER_TAILREC, LOWER_ENUMS),
+    /* ... ... */ LOWER_INNER_CLASSES("Inner classes lowering", LOWER_DEFAULT_PARAMETER_EXTENT),
+    /* ... ... */ LOWER_LATEINIT("Lateinit properties lowering"),
+    /* ... ... */ LOWER_BUILTIN_OPERATORS("BuiltIn Operators Lowering", LOWER_DEFAULT_PARAMETER_EXTENT, LOWER_LATEINIT),
     /* ... ... */ LOWER_TYPE_OPERATORS("Type operators lowering"),
     /* ... ... */ BRIDGES_BUILDING("Bridges building"),
     /* ... ... */ LOWER_STRING_CONCAT("String concatenation lowering"),
-    /* ... ... */ AUTOBOX("Autoboxing of primitive types", setOf(BRIDGES_BUILDING)),
+    /* ... ... */ AUTOBOX("Autoboxing of primitive types", BRIDGES_BUILDING),
     /* ... */ BITCODE("LLVM BitCode Generation"),
     /* ... ... */ RTTI("RTTI Generation"),
     /* ... ... */ CODEGEN("Code Generation"),
     /* ... ... */ METADATOR("Metadata Generation"),
-    /* */ LINKER("Link Stage")
+    /* */ LINKER("Link Stage");
+
+    val prerequisite = prerequisite.toSet()
 }
 
 object KonanPhases {

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

@@ -0,0 +1,57 @@
+package org.jetbrains.kotlin.backend.konan.lower
+
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
+import org.jetbrains.kotlin.backend.konan.Context
+import org.jetbrains.kotlin.backend.konan.descriptors.getKonanInternalFunctions
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
+import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.builders.*
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.declarations.IrProperty
+import org.jetbrains.kotlin.ir.expressions.IrBlock
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
+import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
+import org.jetbrains.kotlin.types.KotlinType
+
+internal class LateinitLowering(val context: Context): FileLoweringPass {
+    override fun lower(irFile: IrFile) {
+        irFile.transformChildrenVoid(object: IrElementTransformerVoid() {
+            override fun visitProperty(declaration: IrProperty): IrStatement {
+                if (declaration.descriptor.isLateInit)
+                    transformGetter(declaration.descriptor, declaration.getter!!)
+                return declaration
+            }
+
+            private fun transformGetter(propertyDescriptor: PropertyDescriptor, getter: IrFunction) {
+                val startOffset = getter.startOffset
+                val endOffset = getter.endOffset
+                val irBuilder = context.createIrBuilder(getter.descriptor, startOffset, endOffset)
+                irBuilder.run {
+                    val block = irBlock(propertyDescriptor.type)
+                    val resultVar = scope.createTemporaryVariable(irGetField(irThis(), propertyDescriptor))
+                    block.statements.add(resultVar)
+                    val throwIfNull = irIfThenElse(context.builtIns.nothingType,
+                            irNotEquals(irGet(resultVar.descriptor), irNull()),
+                            irReturn(irGet(resultVar.descriptor)),
+                            irCall(throwErrorFunction))
+                    block.statements.add(throwIfNull)
+                    getter.body = IrExpressionBodyImpl(startOffset, endOffset, block)
+                }
+            }
+        })
+    }
+
+    private val throwErrorFunction = context.builtIns.getKonanInternalFunctions("ThrowUninitializedPropertyAccessException").single()
+
+    private fun IrBuilderWithScope.irBlock(type: KotlinType): IrBlock
+            = IrBlockImpl(startOffset, endOffset, type)
+
+    private fun IrBuilderWithScope.irGetField(receiver: IrExpression?, property: PropertyDescriptor): IrExpression
+            = IrGetFieldImpl(startOffset, endOffset, property, receiver)
+}

runtime/src/main/kotlin/konan/internal/RuntimeUtils.kt

@@ -24,6 +24,10 @@ fun ThrowNoWhenBranchMatchedException(): Nothing {
     throw NoWhenBranchMatchedException()
 }
 
+fun ThrowUninitializedPropertyAccessException(): Nothing {
+    throw UninitializedPropertyAccessException()
+}
+
 @ExportForCppRuntime
 internal fun TheEmptyString() = ""
 

runtime/src/main/kotlin/kotlin/Exceptions.kt

@@ -176,6 +176,15 @@ public open class NoWhenBranchMatchedException : RuntimeException {
     }
 }
 
+public open class UninitializedPropertyAccessException : RuntimeException {
+
+    constructor() : super() {
+    }
+
+    constructor(s: String) : super(s) {
+    }
+}
+
 public open class OutOfMemoryError : Error {
 
     constructor() : super() {