[IR] Fixed problems with nested inline classes

Fixes https://youtrack.jetbrains.com/issue/KT-45139 as well

(cherry picked from commit 44916e39bfa69325a9ab73cb4533bd2612fb4e56)

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

@@ -42,8 +42,14 @@ private fun KonanSymbols.getTypeConversionImpl(
 internal object DECLARATION_ORIGIN_INLINE_CLASS_SPECIAL_FUNCTION : IrDeclarationOriginImpl("INLINE_CLASS_SPECIAL_FUNCTION")
 
 internal val Context.getBoxFunction: (IrClass) -> IrSimpleFunction by Context.lazyMapMember { inlinedClass ->
-    assert(inlinedClass.isUsedAsBoxClass())
-    assert(inlinedClass.parent is IrFile) { "Expected top level inline class" }
+    require(inlinedClass.isUsedAsBoxClass())
+    val classes = mutableListOf<IrClass>(inlinedClass)
+    var parent = inlinedClass.parent
+    while (parent is IrClass) {
+        classes.add(parent)
+        parent = parent.parent
+    }
+    require(parent is IrFile) { "Local inline classes are not supported" }
 
     val symbols = ir.symbols
 
@@ -61,7 +67,7 @@ internal val Context.getBoxFunction: (IrClass) -> IrSimpleFunction by Context.la
             startOffset, endOffset,
             DECLARATION_ORIGIN_INLINE_CLASS_SPECIAL_FUNCTION,
             IrSimpleFunctionSymbolImpl(),
-            Name.special("<${inlinedClass.name}-box>"),
+            Name.special("<${classes.reversed().joinToString(".") { it.name.asString() }}-box>"),
             DescriptorVisibilities.PUBLIC,
             Modality.FINAL,
             returnType,
@@ -95,8 +101,14 @@ internal val Context.getBoxFunction: (IrClass) -> IrSimpleFunction by Context.la
 }
 
 internal val Context.getUnboxFunction: (IrClass) -> IrSimpleFunction by Context.lazyMapMember { inlinedClass ->
-    assert(inlinedClass.isUsedAsBoxClass())
-    assert(inlinedClass.parent is IrFile) { "Expected top level inline class" }
+    require(inlinedClass.isUsedAsBoxClass())
+    val classes = mutableListOf<IrClass>(inlinedClass)
+    var parent = inlinedClass.parent
+    while (parent is IrClass) {
+        classes.add(parent)
+        parent = parent.parent
+    }
+    require(parent is IrFile) { "Local inline classes are not supported" }
 
     val symbols = ir.symbols
 
@@ -114,7 +126,7 @@ internal val Context.getUnboxFunction: (IrClass) -> IrSimpleFunction by Context.
             startOffset, endOffset,
             DECLARATION_ORIGIN_INLINE_CLASS_SPECIAL_FUNCTION,
             IrSimpleFunctionSymbolImpl(),
-            Name.special("<${inlinedClass.name}-unbox>"),
+            Name.special("<${classes.reversed().joinToString(".") { it.name.asString() } }-unbox>"),
             DescriptorVisibilities.PUBLIC,
             Modality.FINAL,
             returnType,

kotlin-native/backend.native/tests/build.gradle

@@ -3262,6 +3262,10 @@ task inlineClass_secondaryConstructorWithGenerics(type: KonanLocalTest) {
     source = "codegen/inlineClass/secondaryConstructorWithGenerics.kt"
 }
 
+task inlineClass_nestedInlineClasses(type: KonanLocalTest) {
+    source = "codegen/inlineClass/nestedInlineClasses.kt"
+}
+
 task valueClass0(type: KonanLocalTest) {
     source = "codegen/inlineClass/valueClass0.kt"
 }

kotlin-native/backend.native/tests/codegen/inlineClass/nestedInlineClasses.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+
+package codegen.inlineClass.nestedInlineClasses
+
+import kotlin.test.*
+
+interface I {
+    inline class IC(val x: Int)
+}
+
+interface I2 {
+    inline class IC(val x: Int)
+}
+
+@Test fun runTest() {
+    assertEquals(42, I.IC(42).x)
+    assertEquals(117, I2.IC(117).x)
+}