[K/N] Move kotlin.native.internal.GC into kotlin.native.runtime

As a part of efforts to stabilize Native stdlib #KT-55765.

kotlin-native/backend.native/tests/framework/stdlib/stdlib.kt

@@ -4,6 +4,7 @@
  */
 
 @file:Suppress("UNUSED")
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 package stdlib
 
@@ -63,7 +64,7 @@ data class TripleVars<T>(var first: T, var second: T, var third: T) {
     }
 }
 
-fun gc() = kotlin.native.internal.GC.collect()
+fun gc() = kotlin.native.runtime.GC.collect()
 
 // Note: this method checks only some of the operations (namely the ones modified recently,
 // and thus required additional tests).

kotlin-native/backend.native/tests/interop/cleaners/cleaners.kt

@@ -2,9 +2,10 @@
  * Copyright 2010-2020 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.
  */
-@file:OptIn(ExperimentalStdlibApi::class)
+@file:OptIn(ExperimentalStdlibApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlin.native.internal.*
+import kotlin.native.runtime.GC
 
 fun ensureInitialized() {}
 

kotlin-native/backend.native/tests/interop/kt44283/main.kt

@@ -1,3 +1,5 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlinx.cinterop.*
 import kt44283.*
 import kotlin.native.concurrent.AtomicInt
@@ -7,7 +9,7 @@ val callbackCounter = AtomicInt(0)
 
 fun main() {
     val func = staticCFunction<CValue<TestStruct>, Unit> {
-        kotlin.native.internal.GC.collect() // Helps to ensure that "runtime" is already initialized.
+        kotlin.native.runtime.GC.collect() // Helps to ensure that "runtime" is already initialized.
 
         memScoped {
             println("Hello, Kotlin/Native! ${it.ptr.pointed.d}")

kotlin-native/backend.native/tests/interop/objc/smoke.kt

@@ -2,6 +2,7 @@
  * 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.
  */
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlinx.cinterop.*
 import objcSmoke.*
@@ -204,7 +205,7 @@ fun testCustomRetain() {
 
     autoreleasepool {
         test()
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
     }
 
     assertFalse(unexpectedDeallocation)

kotlin-native/backend.native/tests/interop/objc/smoke_noopgc.kt

@@ -2,6 +2,7 @@
  * 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.
  */
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlinx.cinterop.*
 import objcSmoke.*
@@ -204,7 +205,7 @@ fun testCustomRetain() {
 
     autoreleasepool {
         test()
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
     }
 
     assertFalse(unexpectedDeallocation)

kotlin-native/backend.native/tests/interop/objc/tests/customString.kt

@@ -1,3 +1,5 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlinx.cinterop.*
 import kotlin.test.*
 import objcTests.*
@@ -13,7 +15,7 @@ import objcTests.*
     }
 
     test()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     assertTrue(customStringDeallocated)
 }
 

kotlin-native/backend.native/tests/interop/objc/tests/kt41811.kt

@@ -1,3 +1,5 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.native.ref.WeakReference
 import kotlinx.cinterop.*
 import kotlin.test.*
@@ -9,7 +11,7 @@ import objcTests.*
 @Test
 fun testKT41811() {
     // Attempt to make the state predictable:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     deallocRetainReleaseDeallocated = false
     assertFalse(deallocRetainReleaseDeallocated)
@@ -17,12 +19,12 @@ fun testKT41811() {
     createGarbageDeallocRetainRelease()
 
     // Runs [DeallocRetainRelease dealloc]:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(deallocRetainReleaseDeallocated)
 
     // Might crash due to double-dispose if the dealloc applied addRef/releaseRef to reclaimed Kotlin object:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 }
 
 private fun createGarbageDeallocRetainRelease() {
@@ -55,7 +57,7 @@ fun testKT41811LoadKotlinWeak() {
 
 private fun testKT41811LoadWeak(weakRef: WeakReferenceProtocol) {
     // Attempt to make the state predictable:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     deallocLoadWeakDeallocated = false
     assertFalse(deallocLoadWeakDeallocated)
@@ -63,12 +65,12 @@ private fun testKT41811LoadWeak(weakRef: WeakReferenceProtocol) {
     createGarbageDeallocLoadWeak(weakRef)
 
     // Runs [DeallocLoadWeak dealloc]:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(deallocLoadWeakDeallocated)
 
     // Might crash due to double-dispose if the dealloc applied addRef/releaseRef to reclaimed Kotlin object:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     weakDeallocLoadWeak = null
 }
@@ -85,7 +87,7 @@ private fun createGarbageDeallocLoadWeak(weakRef: WeakReferenceProtocol) {
 @Test
 fun testKT41811WithGlobal() {
     // Attempt to make the state predictable:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     deallocRetainReleaseDeallocated = false
     assertFalse(deallocRetainReleaseDeallocated)
@@ -99,7 +101,7 @@ fun testKT41811WithGlobal() {
     assertFalse(deallocRetainReleaseDeallocated)
 
     // Clean up local DeallocRetainRelease on Kotlin side
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertFalse(deallocRetainReleaseDeallocated)
 
@@ -112,7 +114,7 @@ fun testKT41811WithGlobal() {
     // on ObjC side, which triggers `retain` and `release` of `self`. If these messages
     // were to reach Kotlin side, the `release` would have immediately scheduled the
     // second disposal of Kotlin object.
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(deallocRetainReleaseDeallocated)
 }

kotlin-native/backend.native/tests/interop/objc/tests/kt42482.kt

@@ -1,3 +1,5 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.native.ref.WeakReference
 import kotlinx.cinterop.*
 import kotlin.test.*
@@ -6,7 +8,7 @@ import objcTests.*
 @Test
 fun testKT42482() {
     // Attempt to make the state predictable:
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     kt42482Deallocated = false
     assertFalse(kt42482Deallocated);
@@ -25,7 +27,7 @@ fun testKT42482() {
         kt42482Global = null
     }()
 
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(kt42482Deallocated)
 }

kotlin-native/backend.native/tests/interop/objc/tests/objcWeakRefs.kt

@@ -1,4 +1,4 @@
-@file:OptIn(FreezingIsDeprecated::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlinx.cinterop.*
 import kotlin.native.concurrent.*
@@ -16,7 +16,7 @@ import objcTests.*
         testObjCWeakRef0(deallocListener)
     }
 
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     assertTrue(deallocListener.deallocated)
     assertTrue(deallocListener.deallocExecutorIsNil())
 }
@@ -47,6 +47,6 @@ private fun testObjCWeakRef0(deallocListener: DeallocListener) = withWorker {
             assertFalse(deallocListener.deallocExecutorIsNil())
         }
         // Process release of Kotlin reference to [obj] in any case:
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
     }
 }

kotlin-native/backend.native/tests/interop/objc/tests/tryRetainGC.kt

@@ -1,10 +1,12 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlinx.cinterop.*
 import kotlin.test.*
 import objcTests.*
 
 @Test
 fun testTryRetainGC() {
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     val weakRefHolder = WeakRefHolder()
     createGarbageNSObjects(weakRefHolder)
     weakRefHolder.obj = object : NSObject() {}

kotlin-native/backend.native/tests/interop/objc/tests/weakRefs.kt

@@ -1,3 +1,5 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.native.ref.*
 import kotlinx.cinterop.*
 import kotlin.test.*
@@ -16,7 +18,7 @@ private fun testWeakReference(block: () -> NSObject) {
         createAndTestWeakReference(block)
     }
 
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertNull(ref.get())
 }

kotlin-native/backend.native/tests/objcexport/coroutines.kt

@@ -2,6 +2,7 @@
  * Copyright 2010-2020 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.
  */
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 package coroutines
 
@@ -243,4 +244,4 @@ fun createCoroutineUninterceptedAndResume(fn: suspend () -> Any?, resultHolder:
 fun createCoroutineUninterceptedAndResume(fn: suspend Any?.() -> Any?, receiver: Any?, resultHolder: ResultHolder<Any?>) =
         fn.createCoroutine(receiver, ResultHolderCompletion(resultHolder)).resume(Unit)
 
-fun gc() = kotlin.native.internal.GC.collect()
+fun gc() = kotlin.native.runtime.GC.collect()

kotlin-native/backend.native/tests/objcexport/deallocRetain.kt

@@ -7,7 +7,8 @@ package deallocretain
 
 open class DeallocRetainBase
 
-fun garbageCollect() = kotlin.native.internal.GC.collect()
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+fun garbageCollect() = kotlin.native.runtime.GC.collect()
 
 fun createWeakReference(value: Any) = kotlin.native.ref.WeakReference(value)
 

kotlin-native/backend.native/tests/objcexport/noAutorelease.kt

@@ -19,7 +19,8 @@ class KotlinLivenessTracker {
     fun objectsAreDead() = weakRefs.all { it.value === null }
 }
 
-fun gc() = kotlin.native.internal.GC.collect()
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+fun gc() = kotlin.native.runtime.GC.collect()
 
 class KotlinObject
 

kotlin-native/backend.native/tests/objcexport/values.kt

@@ -5,7 +5,7 @@
 
 // All classes and methods should be used in tests
 @file:Suppress("UNUSED")
-@file:OptIn(FreezingIsDeprecated::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 package conversions
 
@@ -807,7 +807,7 @@ open class TestDeprecation() {
 @Deprecated("warning", level = DeprecationLevel.WARNING) var warningVar: Any? = null
 
 fun gc() {
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 }
 
 class TestWeakRefs(private val frozen: Boolean) {
@@ -862,7 +862,7 @@ class SharedRefs {
     fun createFrozenCollection() = createCollection().freeze()
 
     fun hasAliveObjects(): Boolean {
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
         return mustBeRemoved.any { it.get() != null }
     }
 

kotlin-native/backend.native/tests/runtime/basic/cleaner_basic.kt

@@ -2,7 +2,7 @@
  * Copyright 2010-2020 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.
  */
-@file:OptIn(ExperimentalStdlibApi::class, FreezingIsDeprecated::class)
+@file:OptIn(ExperimentalStdlibApi::class, FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 package runtime.basic.cleaner_basic
 
@@ -13,6 +13,7 @@ import kotlin.native.concurrent.*
 import kotlin.native.ref.WeakReference
 import kotlin.native.ref.Cleaner
 import kotlin.native.ref.createCleaner
+import kotlin.native.runtime.GC
 
 class AtomicBoolean(initialValue: Boolean) {
     private val impl = AtomicInt(if (initialValue) 1 else 0)

kotlin-native/backend.native/tests/runtime/basic/cleaner_in_tls_worker.kt

@@ -2,7 +2,7 @@
  * Copyright 2010-2020 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.
  */
-@file:OptIn(ExperimentalStdlibApi::class)
+@file:OptIn(ExperimentalStdlibApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlin.test.*
 
@@ -10,6 +10,7 @@ import kotlin.native.concurrent.*
 import kotlin.native.internal.*
 import kotlin.native.ref.Cleaner
 import kotlin.native.ref.createCleaner
+import kotlin.native.runtime.GC
 
 @ThreadLocal
 var tlsCleaner: Cleaner? = null

kotlin-native/backend.native/tests/runtime/basic/cleaner_workers.kt

@@ -2,7 +2,7 @@
  * Copyright 2010-2020 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.
  */
-@file:OptIn(ExperimentalStdlibApi::class, FreezingIsDeprecated::class, kotlin.experimental.ExperimentalNativeApi::class)
+@file:OptIn(ExperimentalStdlibApi::class, FreezingIsDeprecated::class, kotlin.experimental.ExperimentalNativeApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 package runtime.basic.cleaner_workers
 
@@ -13,6 +13,7 @@ import kotlin.native.concurrent.*
 import kotlin.native.ref.WeakReference
 import kotlin.native.ref.Cleaner
 import kotlin.native.ref.createCleaner
+import kotlin.native.runtime.GC
 
 class AtomicBoolean(initialValue: Boolean) {
     private val impl = AtomicInt(if (initialValue) 1 else 0)

kotlin-native/backend.native/tests/runtime/collections/hash_map1.kt

@@ -7,7 +7,6 @@ package runtime.collections.hash_map1
 
 import kotlin.native.MemoryModel
 import kotlin.native.Platform
-import kotlin.native.internal.GC
 import kotlin.test.*
 
 fun assertTrue(cond: Boolean) {

kotlin-native/backend.native/tests/runtime/concurrent/worker_bound_reference0.kt

@@ -2,16 +2,16 @@
  * Copyright 2010-2020 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.
  */
-@file:OptIn(FreezingIsDeprecated::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 package runtime.concurrent.worker_bound_reference0
 
 import kotlin.test.*
 
 import kotlin.native.concurrent.*
-import kotlin.native.internal.GC
 import kotlin.native.*
 import kotlin.native.ref.WeakReference
+import kotlin.native.runtime.GC
 import kotlin.text.Regex
 
 class A(var a: Int)

kotlin-native/backend.native/tests/runtime/memory/cycle_collector.kt

@@ -1,5 +1,7 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.native.concurrent.*
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 import kotlin.native.Platform
 import kotlin.test.*
 
@@ -44,15 +46,15 @@ fun makeIt(): Holder {
 fun test4() {
     val holder = makeIt()
     // To clean rc count coming from rememberNewContainer().
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     // Request cyclic collection.
-    kotlin.native.internal.GC.collectCyclic()
+    kotlin.native.runtime.GC.collectCyclic()
     // Ensure we processed delayed release.
     repeat(10) {
         // Wait a bit and process queue.
         Worker.current.park(10)
         Worker.current.processQueue()
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
     }
     val value = @Suppress("UNCHECKED_CAST") (holder.other as? AtomicReference<Holder?>?)
     assertTrue(value != null)
@@ -77,15 +79,15 @@ fun createHolder2() = Holder2(createRef())
 
 fun test5() {
     val holder = createHolder2()
-    kotlin.native.internal.GC.collect()
-    kotlin.native.internal.GC.collectCyclic()
+    kotlin.native.runtime.GC.collect()
+    kotlin.native.runtime.GC.collectCyclic()
     Worker.current.park(100 * 1000)
     holder.switch()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     Worker.current.park(100 * 1000)
     withWorker {
         executeAfter(0L, {
-            kotlin.native.internal.GC.collect()
+            kotlin.native.runtime.GC.collect()
         }.freeze())
     }
     Worker.current.park(1000)
@@ -109,9 +111,9 @@ fun createRoot(): AtomicReference<Any?> {
 
 fun test7() {
     val ref1 = createRoot()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
-    kotlin.native.internal.GC.collectCyclic()
+    kotlin.native.runtime.GC.collectCyclic()
     Worker.current.park(500 * 1000L)
 
     withWorker {
@@ -177,7 +179,7 @@ fun test9() {
 
 fun main() {
     Platform.isMemoryLeakCheckerActive = true
-    kotlin.native.internal.GC.cyclicCollectorEnabled = true
+    kotlin.native.runtime.GC.cyclicCollectorEnabled = true
     test1()
     test2()
     test3()

kotlin-native/backend.native/tests/runtime/memory/cycle_collector_deadlock1.kt

@@ -1,9 +1,9 @@
 import kotlin.native.concurrent.*
-import kotlin.native.internal.GC
 import kotlin.test.*
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 fun main() {
-    kotlin.native.internal.GC.cyclicCollectorEnabled = true
+    kotlin.native.runtime.GC.cyclicCollectorEnabled = true
 
     repeat(10000) {
         // Create atomic cyclic garbage:

kotlin-native/backend.native/tests/runtime/memory/cycle_detector.kt

@@ -1,5 +1,7 @@
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.native.concurrent.*
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 import kotlin.native.Platform
 import kotlin.test.*
 

kotlin-native/backend.native/tests/runtime/memory/cycles0.kt

@@ -44,11 +44,12 @@ fun createCycles(junk: Node) {
 
 }
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 @Test fun runTest() {
     // Create outer link from cyclic garbage.
     val outer = Node(42, null, null, null)
     createCycles(outer)
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     // Ensure outer is not collected.
     println(outer.data)
 }

kotlin-native/backend.native/tests/runtime/memory/cycles1.kt

@@ -10,11 +10,12 @@ package runtime.memory.cycles1
 import kotlin.test.*
 import kotlin.native.ref.*
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 @Test fun runTest() {
     // TODO: make it work in relaxed model as well.
     if (Platform.memoryModel == MemoryModel.RELAXED) return
     val weakRefToTrashCycle = createLoop()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     assertNull(weakRefToTrashCycle.get())
 }
 

kotlin-native/backend.native/tests/runtime/memory/gcStats.kt

@@ -3,9 +3,9 @@
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-@file:OptIn(kotlin.ExperimentalStdlibApi::class)
+@file:OptIn(kotlin.ExperimentalStdlibApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 import kotlin.test.*
 
 

kotlin-native/backend.native/tests/runtime/memory/only_gc.kt

@@ -2,8 +2,8 @@
  * 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.
  */
-
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 fun main(args: Array<String>) {
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 }
 

kotlin-native/backend.native/tests/runtime/memory/stress_gc_allocations.kt

@@ -2,6 +2,8 @@
  * Copyright 2010-2021 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.
  */
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
+
 import kotlin.test.*
 
 import kotlin.native.concurrent.*
@@ -58,8 +60,8 @@ fun test() {
     val progressReportsCount = 100
 
     if (Platform.memoryModel == MemoryModel.EXPERIMENTAL) {
-        kotlin.native.internal.GC.autotune = false
-        kotlin.native.internal.GC.targetHeapBytes = retainLimit
+        kotlin.native.runtime.GC.autotune = false
+        kotlin.native.runtime.GC.targetHeapBytes = retainLimit
     }
 
     // On Linux, the child process might immediately commit the same amount of memory as the parent.

kotlin-native/backend.native/tests/runtime/memory/weak0.kt

@@ -28,15 +28,16 @@ fun multiWeak(): Array<WeakReference<Data>>  {
     return weaks
 }
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 @Test fun runTest() {
     val weak = localWeak()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     val value = weak.get()
     println(value?.toString())
 
     val weaks = multiWeak()
 
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     weaks.forEach {
         it -> if (it.get()?.s != null) throw Error("not null")

kotlin-native/backend.native/tests/runtime/workers/atomic1.kt

@@ -4,11 +4,13 @@
  */
 
 // Note: This test reproduces a race, so it'll start flaking if problem is reintroduced.
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlin.test.*
 
 import kotlin.native.concurrent.*
 import kotlin.native.internal.*
+import kotlin.native.runtime.GC
 
 val thrashGC = AtomicInt(1)
 val canStartCreating = AtomicInt(0)

kotlin-native/backend.native/tests/runtime/workers/freeze6.kt

@@ -2,7 +2,7 @@
  * 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.
  */
-@file:OptIn(FreezingIsDeprecated::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 package runtime.workers.freeze6
 
@@ -48,7 +48,7 @@ var global = 0
 @Test
 fun ensureFreezableHandlesCycles1() {
     val ref = createRef1()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     val obj: Any = ref
     global = obj.hashCode()
@@ -86,7 +86,7 @@ fun createRef2(): Pair<FreezableAtomicReference<Node?>, Any> {
 @Test
 fun ensureFreezableHandlesCycles2() {
     val (ref, obj) = createRef2()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(obj.toString().length > 0)
     global = ref.value!!.ref!!.hashCode()
@@ -108,7 +108,7 @@ fun createRef3(): FreezableAtomicReference<Any?> {
 fun ensureFreezableHandlesCycles3() {
     val ref = createRef3()
     ref.value = null
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     val obj: Any = ref
     assertTrue(obj.toString().length > 0)
@@ -133,7 +133,7 @@ fun ensureWeakRefNotLeaks1() {
     ref.value = null
     // We cannot check weakRef.get() here, as value read will be stored in the stack slot,
     // and thus hold weak reference from release.
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
 
     assertTrue(weakRef.get() == null)
 }
@@ -155,6 +155,6 @@ fun createRef5() {
 @Test
 fun ensureWeakRefNotLeaks2() {
     createRef5()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     assertTrue(weakNode2.get() == null)
 }

kotlin-native/backend.native/tests/runtime/workers/lazy2.kt

@@ -24,8 +24,9 @@ fun printAll() {
 // initializer field in frozen lazy object led to the crash, induced by breaking frozen objects'
 // invariant (initializer end up in the same container as the lazy object itself, so it was destroyed
 // earlier than it should when reference counter was decremented).
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 fun main(args: Array<String>) {
     printAll()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     println("OK")
 }

kotlin-native/backend.native/tests/runtime/workers/lazy3.kt

@@ -1,4 +1,4 @@
-@file:OptIn(FreezingIsDeprecated::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlin.native.concurrent.*
 import kotlin.native.ref.*
@@ -49,7 +49,7 @@ fun ensureGetsCollectedFrozenAndNotFrozen(create: () -> Any) {
 
 fun ensureGetsCollected(create: () -> Any) {
     val ref = makeWeakRef(create)
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     assertNull(ref.get())
 }
 

kotlin-native/backend.native/tests/runtime/workers/worker10.kt

@@ -1,4 +1,4 @@
-@file:OptIn(FreezingIsDeprecated::class, kotlin.experimental.ExperimentalNativeApi::class)
+@file:OptIn(FreezingIsDeprecated::class, kotlin.experimental.ExperimentalNativeApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 package runtime.workers.worker10
 
 import kotlin.test.*
@@ -99,7 +99,7 @@ val semaphore = AtomicInt(0)
     }
     while (semaphore.value != 1) {}
     atomicRef.value = null
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     semaphore.increment()
     future.result
     worker.requestTermination().result
@@ -116,7 +116,7 @@ val semaphore = AtomicInt(0)
     }
     while (semaphore.value != 1) {}
     stableRef.dispose()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     semaphore.increment()
     future.result
     worker.requestTermination().result
@@ -135,12 +135,12 @@ val stableHolder1 = StableRef.create(("hello" to "world").freeze())
         ensureWeakIs(it, "hello" to "world")
         semaphore.increment()
         while (semaphore.value != 2) {}
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
         ensureWeakIs(it, null)
     }
     while (semaphore.value != 1) {}
     stableHolder1.dispose()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     semaphore.increment()
     future.result
     worker.requestTermination().result
@@ -155,12 +155,12 @@ val stableHolder2 = StableRef.create(("hello" to "world").freeze())
         val value = it.get()
         semaphore.increment()
         while (semaphore.value != 2) {}
-        kotlin.native.internal.GC.collect()
+        kotlin.native.runtime.GC.collect()
         assertEquals("hello" to "world", value)
     }
     while (semaphore.value != 1) {}
     stableHolder2.dispose()
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     semaphore.increment()
     future.result
     worker.requestTermination().result
@@ -178,7 +178,7 @@ val atomicRef2 = AtomicReference<Any?>(Any().freeze())
     }
     while (semaphore.value != 1) {}
     atomicRef2.value = null
-    kotlin.native.internal.GC.collect()
+    kotlin.native.runtime.GC.collect()
     semaphore.increment()
     future.result
     worker.requestTermination().result

kotlin-native/backend.native/tests/runtime/workers/worker9.kt

@@ -80,12 +80,13 @@ fun makeCyclic(): Node {
     return outer
 }
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 @Test fun runTest4() {
     val worker = Worker.start()
 
     val future = worker.execute(TransferMode.SAFE, { }) {
         makeCyclic().also {
-            kotlin.native.internal.GC.collect()
+            kotlin.native.runtime.GC.collect()
         }
     }
     assert(future.result != null)

kotlin-native/backend.native/tests/runtime/workers/worker9_experimentalMM.kt

@@ -78,12 +78,13 @@ fun makeCyclic(): Node {
     return outer
 }
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 @Test fun runTest4() {
     val worker = Worker.start()
 
     val future = worker.execute(TransferMode.SAFE, { }) {
         makeCyclic().also {
-            kotlin.native.internal.GC.collect()
+            kotlin.native.runtime.GC.collect()
         }
     }
     assert(future.result != null)

kotlin-native/performance/ring/src/main/kotlin-native/cleanup.kt

@@ -1,5 +1,6 @@
 package org.jetbrains.ring
 
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 actual fun cleanup() { GC.collect() }

kotlin-native/performance/ring/src/main/kotlin/org/jetbrains/ring/WeakRefBenchmark.kt

@@ -5,7 +5,7 @@
 
 package org.jetbrains.ring
 
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 import kotlin.native.ref.WeakReference
 import kotlin.test.assertEquals
 import kotlin.test.assertNotEquals
@@ -46,6 +46,7 @@ private fun ReferenceWrapper.stress() = (1..REPEAT_COUNT).sumOf {
     this.value
 }
 
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 open class WeakRefBenchmark {
     private val aliveRef = ReferenceWrapper.create()
     private val deadRef = ReferenceWrapper.create().apply {

kotlin-native/performance/shared/src/main/kotlin-native/common/org/jetbrains/benchmarksLauncher/Utils.kt

@@ -16,7 +16,7 @@
 
 package org.jetbrains.benchmarksLauncher
 
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 import platform.posix.*
 import kotlinx.cinterop.*
 
@@ -39,6 +39,7 @@ actual inline fun measureNanoTime(block: () -> Unit): Long {
     return kotlin.system.measureNanoTime(block)
 }
 
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 actual fun cleanup() {
     GC.collect()
 }

kotlin-native/performance/swiftinterop/src/main/kotlin/org/jetbrains/GC.kt

@@ -2,10 +2,11 @@
  * Copyright 2010-2022 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.
  */
+@file:OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 
 package org.jetbrains.gc
 
-import kotlin.native.internal.GC
+import kotlin.native.runtime.GC
 
 fun collect() = GC.collect()
 fun schedule() = GC.schedule()

kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/Atomics.kt

@@ -187,7 +187,7 @@ private fun debugString(value: Any?): String {
  *
  * Legacy MM: An atomic reference to a frozen Kotlin object. Can be used in concurrent scenarious
  * but frequently shall be of nullable type and be zeroed out once no longer needed.
- * Otherwise memory leak could happen. To detect such leaks [kotlin.native.internal.GC.detectCycles]
+ * Otherwise memory leak could happen. To detect such leaks [kotlin.native.runtime.GC.detectCycles]
  * in debug mode could be helpful.
  */
 @FrozenLegacyMM
@@ -284,7 +284,7 @@ public class AtomicReference<T> {
  *
  * An atomic reference to a Kotlin object. Can be used in concurrent scenarious, but must be frozen first,
  * otherwise behaves as regular box for the value. If frozen, shall be zeroed out once no longer needed.
- * Otherwise memory leak could happen. To detect such leaks [kotlin.native.internal.GC.detectCycles]
+ * Otherwise memory leak could happen. To detect such leaks [kotlin.native.runtime.GC.detectCycles]
  * in debug mode could be helpful.
  */
 @NoReorderFields

kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/ObjectTransfer.kt

@@ -33,7 +33,7 @@ import kotlin.native.internal.Frozen
  *   Note, that for some cases cycle collection need to be done to ensure that dead cycles do not affect
  *  reachability of passed object graph.
  *
- *  @see [kotlin.native.internal.GC.collect].
+ *  @see [kotlin.native.runtime.GC.collect].
  */
 // Not @FreezingIsDeprecated: every `Worker.execute` uses this.
 public enum class TransferMode(val value: Int) {

kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/Worker.kt

@@ -100,7 +100,7 @@ public value class Worker @PublishedApi internal constructor(val id: Int) {
      * and result of such a execution is being disconnected from worker's object graph. Whoever will consume
      * the future, can use result of worker's computations.
      * Note, that some technically disjoint subgraphs may lead to `kotlin.IllegalStateException`
-     * so `kotlin.native.internal.GC.collect()` could be called in the end of `producer` and `job`
+     * so `kotlin.native.runtime.GC.collect()` could be called in the end of `producer` and `job`
      * if garbage cyclic structures or other uncollected objects refer to the value being transferred.
      *
      * @return the future with the computation result of [job].

kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/Cleaner.kt

@@ -7,6 +7,7 @@ package kotlin.native.internal
 
 import kotlin.experimental.ExperimentalNativeApi
 import kotlin.native.concurrent.*
+import kotlin.native.runtime.GC
 import kotlinx.cinterop.NativePtr
 
 @Deprecated("Use kotlin.native.ref.Cleaner instead.", ReplaceWith("kotlin.native.ref.Cleaner"))
@@ -83,6 +84,7 @@ fun <T> createCleaner(argument: T, block: (T) -> Unit): Cleaner =
  * Perform GC on a worker that executes Cleaner blocks.
  */
 @InternalForKotlinNative
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 fun performGCOnCleanerWorker() =
     getCleanerWorker().execute(TransferMode.SAFE, {}) {
         GC.collect()

kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/GC.kt

@@ -5,9 +5,7 @@
 
 package kotlin.native.internal
 
-import kotlin.native.internal.gc.GCInfo
 import kotlin.time.*
-import kotlin.time.Duration.Companion.microseconds
 
 /**
  * __Note__: this API is unstable and may change in any release.
@@ -34,6 +32,9 @@ import kotlin.time.Duration.Companion.microseconds
  * its lifetime, and resume it later on, or just completely turn it off, if GC pauses
  * are less desirable than cyclical garbage leaks.
  */
+@Deprecated("Use kotlin.native.runtime.GC instead.", ReplaceWith("GC", "kotlin.native.runtime.GC"))
+@DeprecatedSinceKotlin(warningSince = "1.9")
+@OptIn(kotlin.native.runtime.NativeRuntimeApi::class)
 object GC {
     /**
      * Trigger new collection and wait for its completion.
@@ -108,12 +109,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is not positive.
      */
-    var threshold: Int
-        get() = getThreshold()
-        set(value) {
-            require(value > 0) { "threshold must be positive: $value" }
-            setThreshold(value)
-        }
+    var threshold: Int by kotlin.native.runtime.GC::threshold
 
     /**
      * Deprecated and unused.
@@ -125,13 +121,9 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is not positive.
      */
+    @Suppress("DEPRECATION")
     @Deprecated("No-op in modern GC implementation")
-    var collectCyclesThreshold: Long
-        get() = getCollectCyclesThreshold()
-        set(value) {
-            require(value > 0) { "collectCyclesThreshold must be positive: $value" }
-            setCollectCyclesThreshold(value)
-        }
+    var collectCyclesThreshold: Long by kotlin.native.runtime.GC::collectCyclesThreshold
 
     /**
      * How many bytes a thread can allocate before informing the GC scheduler.
@@ -145,12 +137,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is not positive.
      */
-    var thresholdAllocations: Long
-        get() = getThresholdAllocations()
-        set(value) {
-            require(value > 0) { "thresholdAllocations must be positive: $value" }
-            setThresholdAllocations(value)
-        }
+    var thresholdAllocations: Long by kotlin.native.runtime.GC::thresholdAllocations
 
     /**
      * If true update targetHeapBytes after each collection.
@@ -159,9 +146,7 @@ object GC {
      *
      * Default: true
      */
-    var autotune: Boolean
-        get() = getTuneThreshold()
-        set(value) = setTuneThreshold(value)
+    var autotune: Boolean by kotlin.native.runtime.GC::autotune
 
 
     /**
@@ -169,10 +154,9 @@ object GC {
      *
      * Legacy MM: If cyclic collector for atomic references to be deployed.
      */
+    @Suppress("DEPRECATION")
     @Deprecated("No-op in modern GC implementation")
-    var cyclicCollectorEnabled: Boolean
-        get() = getCyclicCollectorEnabled()
-        set(value) = setCyclicCollectorEnabled(value)
+    var cyclicCollectorEnabled: Boolean by kotlin.native.runtime.GC::cyclicCollectorEnabled
 
     /**
      * When Kotlin code is not allocating enough to trigger GC, the GC scheduler uses timer to drive collection.
@@ -186,12 +170,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is negative.
      */
-     var regularGCInterval: Duration
-        get() = getRegularGCIntervalMicroseconds().microseconds
-        set(value) {
-            require(!value.isNegative()) { "regularGCInterval must not be negative: $value" }
-            setRegularGCIntervalMicroseconds(value.inWholeMicroseconds)
-        }
+     var regularGCInterval: Duration by kotlin.native.runtime.GC::regularGCInterval
 
     /**
      * Total amount of heap available for Kotlin objects. When Kotlin objects overflow this heap,
@@ -208,12 +187,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is negative.
      */
-    var targetHeapBytes: Long
-        get() = getTargetHeapBytes()
-        set(value) {
-            require(value >= 0) { "targetHeapBytes must not be negative: $value" }
-            setTargetHeapBytes(value)
-        }
+    var targetHeapBytes: Long by kotlin.native.runtime.GC::targetHeapBytes
 
     /**
      * What fraction of the Kotlin heap should be populated.
@@ -225,12 +199,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is outside (0, 1] interval.
      */
-     var targetHeapUtilization: Double
-        get() = getTargetHeapUtilization()
-        set(value) {
-            require(value > 0 && value <= 1) { "targetHeapUtilization must be in (0, 1] interval: $value" }
-            setTargetHeapUtilization(value)
-        }
+     var targetHeapUtilization: Double by kotlin.native.runtime.GC::targetHeapUtilization
 
     /**
      * The minimum value for [targetHeapBytes]
@@ -242,12 +211,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is negative.
      */
-     var minHeapBytes: Long
-        get() = getMinHeapBytes()
-        set(value) {
-            require(value >= 0) { "minHeapBytes must not be negative: $value" }
-            setMinHeapBytes(value)
-        }
+     var minHeapBytes: Long by kotlin.native.runtime.GC::minHeapBytes
 
     /**
      * The maximum value for [targetHeapBytes].
@@ -259,12 +223,7 @@ object GC {
      *
      * @throws [IllegalArgumentException] when value is negative.
      */
-     var maxHeapBytes: Long
-        get() = getMaxHeapBytes()
-        set(value) {
-            require(value >= 0) { "maxHeapBytes must not be negative: $value" }
-            setMaxHeapBytes(value)
-        }
+     var maxHeapBytes: Long by kotlin.native.runtime.GC::maxHeapBytes
 
     /**
      * Deprecated and unused. Always returns null.
@@ -286,75 +245,7 @@ object GC {
      * Legacy MM: Always returns null
      */
     @ExperimentalStdlibApi
-    val lastGCInfo: GCInfo?
-        get() = GCInfo.lastGCInfo
-
-    /**
-     * Deprecated and unused. Always returns null.
-     *
-     * Legacy MM: Find a reference cycle including from the given object, `null` if no cycles detected.
-     */
-    @GCUnsafeCall("Kotlin_native_internal_GC_findCycle")
-    @Deprecated("No-op in modern GC implementation")
-    external fun findCycle(root: Any): Array<Any>?
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getThreshold")
-    private external fun getThreshold(): Int
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setThreshold")
-    private external fun setThreshold(value: Int)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getCollectCyclesThreshold")
-    private external fun getCollectCyclesThreshold(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setCollectCyclesThreshold")
-    private external fun setCollectCyclesThreshold(value: Long)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getThresholdAllocations")
-    private external fun getThresholdAllocations(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setThresholdAllocations")
-    private external fun setThresholdAllocations(value: Long)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getTuneThreshold")
-    private external fun getTuneThreshold(): Boolean
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setTuneThreshold")
-    private external fun setTuneThreshold(value: Boolean)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getCyclicCollector")
-    private external fun getCyclicCollectorEnabled(): Boolean
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setCyclicCollector")
-    private external fun setCyclicCollectorEnabled(value: Boolean)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getRegularGCIntervalMicroseconds")
-    private external fun getRegularGCIntervalMicroseconds(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setRegularGCIntervalMicroseconds")
-    private external fun setRegularGCIntervalMicroseconds(value: Long)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getTargetHeapBytes")
-    private external fun getTargetHeapBytes(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setTargetHeapBytes")
-    private external fun setTargetHeapBytes(value: Long)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getTargetHeapUtilization")
-    private external fun getTargetHeapUtilization(): Double
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setTargetHeapUtilization")
-    private external fun setTargetHeapUtilization(value: Double)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getMinHeapBytes")
-    private external fun getMinHeapBytes(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setMinHeapBytes")
-    private external fun setMinHeapBytes(value: Long)
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_getMaxHeapBytes")
-    private external fun getMaxHeapBytes(): Long
-
-    @GCUnsafeCall("Kotlin_native_internal_GC_setMaxHeapBytes")
-    private external fun setMaxHeapBytes(value: Long)
+    @Suppress("DEPRECATION")
+    val lastGCInfo: kotlin.native.internal.gc.GCInfo?
+        get() = kotlin.native.internal.gc.GCInfo.lastGCInfo
 }

kotlin-native/runtime/src/main/kotlin/kotlin/native/runtime/GC.kt

@@ -0,0 +1,362 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin.native.runtime
+
+import kotlin.time.*
+import kotlin.time.Duration.Companion.microseconds
+import kotlin.native.internal.GCUnsafeCall
+
+/**
+ * __Note__: this API is unstable and may change in any release.
+ *
+ * Kotlin/Native uses tracing garbage collector (GC) that is executed periodically to collect objects
+ * that are not reachable from the "roots", like local and global variables.
+ * See [documentation](https://kotlinlang.org/docs/native-memory-manager.html) to learn more about
+ * Kotlin/Native memory management.
+ *
+ * This object provides a set of functions and properties that allows to tune garbage collector.
+ *
+ * __Legacy memory manager__
+ *
+ * Kotlin/Native relies upon reference counting for object management, however it could
+ * not collect cyclical garbage, so we perform periodic garbage collection.
+ * This may slow down application, so this interface provides control over how
+ * garbage collector activates and runs.
+ * Garbage collector can be in one of the following states:
+ *  - running
+ *  - suspended (so cycle candidates are collected, but GC is not performed until resume)
+ *  - stopped (all cyclical garbage is hopelessly lost)
+ * Immediately after startup GC is in running state.
+ * Depending on application needs it may select to suspend GC for certain phases of
+ * its lifetime, and resume it later on, or just completely turn it off, if GC pauses
+ * are less desirable than cyclical garbage leaks.
+ */
+@NativeRuntimeApi
+@SinceKotlin("1.9")
+public object GC {
+    /**
+     * Trigger new collection and wait for its completion.
+     *
+     * Legacy MM: force garbage collection immediately, unless collector is stopped
+     * with [stop] operation. Even if GC is suspended, [collect] still triggers collection.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_collect")
+    external fun collect()
+
+    /**
+     * Trigger new collection without waiting for its completion.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_schedule")
+    external fun schedule()
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: Request global cyclic collector, operation is async and just triggers the collection.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_collectCyclic")
+    @Deprecated("No-op in modern GC implementation")
+    external fun collectCyclic()
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: Suspend garbage collection. Release candidates are still collected, but
+     * GC algorithm is not executed.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_suspend")
+    external fun suspend()
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: Resume garbage collection. Can potentially lead to GC immediately.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_resume")
+    @Deprecated("No-op in modern GC implementation")
+    external fun resume()
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: Stop garbage collection. Cyclical garbage is no longer collected.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_stop")
+    @Deprecated("No-op in modern GC implementation")
+    external fun stop()
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: Start garbage collection. Cyclical garbage produced while GC was stopped
+     * cannot be reclaimed, but all new garbage is collected.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_start")
+    @Deprecated("No-op in modern GC implementation")
+    external fun start()
+
+    /**
+     * GC threshold, controlling how frequenly GC is activated, and how much time GC
+     * takes. Bigger values lead to longer GC pauses, but less GCs.
+     * Usually unused. For the on-safepoints GC scheduler counts
+     *         how many safepoints must the code pass before informing the GC scheduler.
+     *
+     * Default: (old MM) 8 * 1024
+     *
+     * Default: (new MM) 100000
+     *
+     * @throws [IllegalArgumentException] when value is not positive.
+     */
+    var threshold: Int
+        get() = getThreshold()
+        set(value) {
+            require(value > 0) { "threshold must be positive: $value" }
+            setThreshold(value)
+        }
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: GC allocation threshold, controlling how frequenly GC collect cycles, and how much time
+     * this process takes. Bigger values lead to longer GC pauses, but less GCs.
+     *
+     * Default: 8 * 1024
+     *
+     * @throws [IllegalArgumentException] when value is not positive.
+     */
+    @Deprecated("No-op in modern GC implementation")
+    var collectCyclesThreshold: Long
+        get() = getCollectCyclesThreshold()
+        set(value) {
+            require(value > 0) { "collectCyclesThreshold must be positive: $value" }
+            setCollectCyclesThreshold(value)
+        }
+
+    /**
+     * How many bytes a thread can allocate before informing the GC scheduler.
+     *
+     * Default: 10 * 1024
+     *
+     * Legacy MM: GC allocation threshold, controlling how many bytes allocated since last
+     * collection will trigger new GC.
+     *
+     * Default: (legacy MM) 8 * 1024 * 1024
+     *
+     * @throws [IllegalArgumentException] when value is not positive.
+     */
+    var thresholdAllocations: Long
+        get() = getThresholdAllocations()
+        set(value) {
+            require(value > 0) { "thresholdAllocations must be positive: $value" }
+            setThresholdAllocations(value)
+        }
+
+    /**
+     * If true update targetHeapBytes after each collection.
+     *
+     * Legacy MM: If GC shall auto-tune thresholds, depending on how much time is spent in collection.
+     *
+     * Default: true
+     */
+    var autotune: Boolean
+        get() = getTuneThreshold()
+        set(value) = setTuneThreshold(value)
+
+
+    /**
+     * Deprecated and unused.
+     *
+     * Legacy MM: If cyclic collector for atomic references to be deployed.
+     */
+    @Deprecated("No-op in modern GC implementation")
+    var cyclicCollectorEnabled: Boolean
+        get() = getCyclicCollectorEnabled()
+        set(value) = setCyclicCollectorEnabled(value)
+
+    /**
+     * When Kotlin code is not allocating enough to trigger GC, the GC scheduler uses timer to drive collection.
+     * Timer-triggered collection will happen roughly in [regularGCInterval] .. 2 * [regularGCInterval] since
+     * any previous collection.
+     * Unused with on-safepoints GC scheduler.
+     *
+     * Default: 10 seconds
+     *
+     * Unused in legacy MM.
+     *
+     * @throws [IllegalArgumentException] when value is negative.
+     */
+    var regularGCInterval: Duration
+        get() = getRegularGCIntervalMicroseconds().microseconds
+        set(value) {
+            require(!value.isNegative()) { "regularGCInterval must not be negative: $value" }
+            setRegularGCIntervalMicroseconds(value.inWholeMicroseconds)
+        }
+
+    /**
+     * Total amount of heap available for Kotlin objects. When Kotlin objects overflow this heap,
+     * the garbage collection is requested. Automatically adjusts when [autotune] is true:
+     * after each collection the [targetHeapBytes] is set to heapBytes / [targetHeapUtilization] and
+     * capped between [minHeapBytes] and [maxHeapBytes], where heapBytes is heap usage after the garbage
+     * is collected.
+     * Note, that if after a collection heapBytes > [targetHeapBytes] (which may happen if [autotune] is false,
+     * or [maxHeapBytes] is set too low), the next collection will be triggered almost immediately.
+     *
+     * Default: 1 MiB
+     *
+     * Unused in legacy MM.
+     *
+     * @throws [IllegalArgumentException] when value is negative.
+     */
+    var targetHeapBytes: Long
+        get() = getTargetHeapBytes()
+        set(value) {
+            require(value >= 0) { "targetHeapBytes must not be negative: $value" }
+            setTargetHeapBytes(value)
+        }
+
+    /**
+     * What fraction of the Kotlin heap should be populated.
+     * Only used if [autotune] is true. See [targetHeapBytes] for more details.
+     *
+     * Default: 0.5
+     *
+     * Unused in legacy MM.
+     *
+     * @throws [IllegalArgumentException] when value is outside (0, 1] interval.
+     */
+    var targetHeapUtilization: Double
+        get() = getTargetHeapUtilization()
+        set(value) {
+            require(value > 0 && value <= 1) { "targetHeapUtilization must be in (0, 1] interval: $value" }
+            setTargetHeapUtilization(value)
+        }
+
+    /**
+     * The minimum value for [targetHeapBytes]
+     * Only used if [autotune] is true. See [targetHeapBytes] for more details.
+     *
+     * Default: 1 MiB
+     *
+     * Unused in legacy MM.
+     *
+     * @throws [IllegalArgumentException] when value is negative.
+     */
+    var minHeapBytes: Long
+        get() = getMinHeapBytes()
+        set(value) {
+            require(value >= 0) { "minHeapBytes must not be negative: $value" }
+            setMinHeapBytes(value)
+        }
+
+    /**
+     * The maximum value for [targetHeapBytes].
+     * Only used if [autotune] is true. See [targetHeapBytes] for more details.
+     *
+     * Default: [Long.MAX_VALUE]
+     *
+     * Unused in legacy MM.
+     *
+     * @throws [IllegalArgumentException] when value is negative.
+     */
+    var maxHeapBytes: Long
+        get() = getMaxHeapBytes()
+        set(value) {
+            require(value >= 0) { "maxHeapBytes must not be negative: $value" }
+            setMaxHeapBytes(value)
+        }
+
+    /**
+     * Deprecated and unused. Always returns null.
+     *
+     * Legacy MM: Detect cyclic references going via atomic references and return list of cycle-inducing objects
+     * or `null` if the leak detector is not available. Use [Platform.isMemoryLeakCheckerActive] to check
+     * leak detector availability.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_detectCycles")
+    @Deprecated("No-op in modern GC implementation")
+    external fun detectCycles(): Array<Any>?
+
+    /**
+     * Returns statistics of the last finished garbage collection run.
+     * This information is supposed to be used for testing and debugging purposes only
+     *
+     * Can return null, if there was no garbage collection runs yet.
+     *
+     * Legacy MM: Always returns null
+     */
+    @ExperimentalStdlibApi
+    val lastGCInfo: GCInfo?
+        get() = GCInfo.lastGCInfo
+
+    /**
+     * Deprecated and unused. Always returns null.
+     *
+     * Legacy MM: Find a reference cycle including from the given object, `null` if no cycles detected.
+     */
+    @GCUnsafeCall("Kotlin_native_internal_GC_findCycle")
+    @Deprecated("No-op in modern GC implementation")
+    external fun findCycle(root: Any): Array<Any>?
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getThreshold")
+    private external fun getThreshold(): Int
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setThreshold")
+    private external fun setThreshold(value: Int)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getCollectCyclesThreshold")
+    private external fun getCollectCyclesThreshold(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setCollectCyclesThreshold")
+    private external fun setCollectCyclesThreshold(value: Long)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getThresholdAllocations")
+    private external fun getThresholdAllocations(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setThresholdAllocations")
+    private external fun setThresholdAllocations(value: Long)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getTuneThreshold")
+    private external fun getTuneThreshold(): Boolean
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setTuneThreshold")
+    private external fun setTuneThreshold(value: Boolean)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getCyclicCollector")
+    private external fun getCyclicCollectorEnabled(): Boolean
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setCyclicCollector")
+    private external fun setCyclicCollectorEnabled(value: Boolean)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getRegularGCIntervalMicroseconds")
+    private external fun getRegularGCIntervalMicroseconds(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setRegularGCIntervalMicroseconds")
+    private external fun setRegularGCIntervalMicroseconds(value: Long)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getTargetHeapBytes")
+    private external fun getTargetHeapBytes(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setTargetHeapBytes")
+    private external fun setTargetHeapBytes(value: Long)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getTargetHeapUtilization")
+    private external fun getTargetHeapUtilization(): Double
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setTargetHeapUtilization")
+    private external fun setTargetHeapUtilization(value: Double)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getMinHeapBytes")
+    private external fun getMinHeapBytes(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setMinHeapBytes")
+    private external fun setMinHeapBytes(value: Long)
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_getMaxHeapBytes")
+    private external fun getMaxHeapBytes(): Long
+
+    @GCUnsafeCall("Kotlin_native_internal_GC_setMaxHeapBytes")
+    private external fun setMaxHeapBytes(value: Long)
+}