diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeAttributes.kt b/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeAttributes.kt
index 8e613445f7f..81b224c8d62 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeAttributes.kt
+++ b/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeAttributes.kt
@@ -5,8 +5,8 @@
 
 package org.jetbrains.kotlin.fir.types
 
-import org.jetbrains.kotlin.fir.utils.AttributeArrayOwner
-import org.jetbrains.kotlin.fir.utils.TypeRegistry
+import org.jetbrains.kotlin.util.AttributeArrayOwner
+import org.jetbrains.kotlin.util.TypeRegistry
 import org.jetbrains.kotlin.types.model.AnnotationMarker
 import org.jetbrains.kotlin.utils.addIfNotNull
 import kotlin.properties.ReadOnlyProperty
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/impl/Impl.kt b/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/impl/Impl.kt
index 61edb9682e6..c284a417324 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/impl/Impl.kt
+++ b/compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/impl/Impl.kt
@@ -10,7 +10,7 @@ import org.jetbrains.kotlin.fir.types.ConeAttributes
 import org.jetbrains.kotlin.fir.types.ConeClassLikeType
 import org.jetbrains.kotlin.fir.types.ConeTypeProjection
 import org.jetbrains.kotlin.fir.types.ConeNullability
-import org.jetbrains.kotlin.fir.utils.WeakPair
+import org.jetbrains.kotlin.util.WeakPair
 
 class ConeClassLikeTypeImpl(
     override val lookupTag: ConeClassLikeLookupTag,
diff --git a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
index 3c67444e2cc..b6c50184b5f 100644
--- a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
+++ b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
@@ -25,10 +25,10 @@ import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.types.builder.buildResolvedTypeRef
 import org.jetbrains.kotlin.fir.types.impl.ConeClassLikeTypeImpl
-import org.jetbrains.kotlin.fir.utils.WeakPair
 import org.jetbrains.kotlin.name.SpecialNames
 import org.jetbrains.kotlin.name.StandardClassIds
 import org.jetbrains.kotlin.types.ConstantValueKind
+import org.jetbrains.kotlin.util.WeakPair
 
 fun ConeClassifierLookupTag.toSymbol(useSiteSession: FirSession): FirClassifierSymbol<*>? =
     when (this) {
diff --git a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/TypeExpansionUtils.kt b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/TypeExpansionUtils.kt
index 4c6c1c1d321..e490d283d7a 100644
--- a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/TypeExpansionUtils.kt
+++ b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/TypeExpansionUtils.kt
@@ -15,9 +15,9 @@ import org.jetbrains.kotlin.fir.symbols.impl.FirTypeAliasSymbol
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.types.impl.ConeClassLikeTypeImpl
 import org.jetbrains.kotlin.fir.types.impl.ConeTypeParameterTypeImpl
-import org.jetbrains.kotlin.fir.utils.WeakPair
-import org.jetbrains.kotlin.fir.utils.component1
-import org.jetbrains.kotlin.fir.utils.component2
+import org.jetbrains.kotlin.util.WeakPair
+import org.jetbrains.kotlin.util.component1
+import org.jetbrains.kotlin.util.component2
 
 fun ConeClassLikeType.fullyExpandedType(
     useSiteSession: FirSession,
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSession.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSession.kt
index bf196a01e23..6a2c30f7368 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSession.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSession.kt
@@ -6,10 +6,10 @@
 package org.jetbrains.kotlin.fir
 
 import org.jetbrains.kotlin.fir.types.impl.*
-import org.jetbrains.kotlin.fir.utils.ArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.ComponentArrayOwner
-import org.jetbrains.kotlin.fir.utils.NullableArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.TypeRegistry
+import org.jetbrains.kotlin.util.ArrayMapAccessor
+import org.jetbrains.kotlin.util.ComponentArrayOwner
+import org.jetbrains.kotlin.util.NullableArrayMapAccessor
+import org.jetbrains.kotlin.util.TypeRegistry
 import kotlin.reflect.KClass
 
 interface FirSessionComponent
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationAttributes.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationAttributes.kt
index 314ce38424f..794af7e9f91 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationAttributes.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationAttributes.kt
@@ -5,10 +5,10 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.utils.ArrayMap
-import org.jetbrains.kotlin.fir.utils.AttributeArrayOwner
-import org.jetbrains.kotlin.fir.utils.NullableArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.TypeRegistry
+import org.jetbrains.kotlin.util.ArrayMap
+import org.jetbrains.kotlin.util.AttributeArrayOwner
+import org.jetbrains.kotlin.util.NullableArrayMapAccessor
+import org.jetbrains.kotlin.util.TypeRegistry
 import kotlin.properties.ReadWriteProperty
 import kotlin.reflect.KClass
 import kotlin.reflect.KProperty
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/extensions/FirExtensionService.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/extensions/FirExtensionService.kt
index bba3aa7d28b..a95689ea53f 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/extensions/FirExtensionService.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/extensions/FirExtensionService.kt
@@ -8,9 +8,9 @@ package org.jetbrains.kotlin.fir.extensions
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSessionComponent
 import org.jetbrains.kotlin.fir.NoMutableState
-import org.jetbrains.kotlin.fir.utils.ArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.ComponentArrayOwner
-import org.jetbrains.kotlin.fir.utils.TypeRegistry
+import org.jetbrains.kotlin.util.ArrayMapAccessor
+import org.jetbrains.kotlin.util.ComponentArrayOwner
+import org.jetbrains.kotlin.util.TypeRegistry
 import kotlin.reflect.KClass
 
 @RequiresOptIn
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/ConeClassLikeLookupTagImpl.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/ConeClassLikeLookupTagImpl.kt
index 018588cb8ce..1a7f8e604a8 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/ConeClassLikeLookupTagImpl.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/ConeClassLikeLookupTagImpl.kt
@@ -7,7 +7,7 @@ package org.jetbrains.kotlin.fir.symbols.impl
 
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.symbols.ConeClassLikeLookupTag
-import org.jetbrains.kotlin.fir.utils.WeakPair
+import org.jetbrains.kotlin.util.WeakPair
 import org.jetbrains.kotlin.name.ClassId
 
 @RequiresOptIn
diff --git a/compiler/test-infrastructure/tests/org/jetbrains/kotlin/test/services/TestServices.kt b/compiler/test-infrastructure/tests/org/jetbrains/kotlin/test/services/TestServices.kt
index 14925deae62..9af8e0901cd 100644
--- a/compiler/test-infrastructure/tests/org/jetbrains/kotlin/test/services/TestServices.kt
+++ b/compiler/test-infrastructure/tests/org/jetbrains/kotlin/test/services/TestServices.kt
@@ -5,10 +5,10 @@
 
 package org.jetbrains.kotlin.test.services
 
-import org.jetbrains.kotlin.fir.utils.ArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.ComponentArrayOwner
-import org.jetbrains.kotlin.fir.utils.NullableArrayMapAccessor
-import org.jetbrains.kotlin.fir.utils.TypeRegistry
+import org.jetbrains.kotlin.util.ArrayMapAccessor
+import org.jetbrains.kotlin.util.ComponentArrayOwner
+import org.jetbrains.kotlin.util.NullableArrayMapAccessor
+import org.jetbrains.kotlin.util.TypeRegistry
 import kotlin.reflect.KClass
 
 interface TestService
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMap.kt b/core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMap.kt
similarity index 97%
rename from compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMap.kt
rename to core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMap.kt
index 742f0367141..1feab358db5 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMap.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMap.kt
@@ -1,9 +1,9 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 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 org.jetbrains.kotlin.fir.utils
+package org.jetbrains.kotlin.util
 
 sealed class ArrayMap<T : Any> : Iterable<T> {
     abstract val size: Int
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMapOwner.kt b/core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMapOwner.kt
similarity index 96%
rename from compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMapOwner.kt
rename to core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMapOwner.kt
index 8f347228d5e..a0a96a5d85b 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMapOwner.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/util/ArrayMapOwner.kt
@@ -1,9 +1,9 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 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 org.jetbrains.kotlin.fir.utils
+package org.jetbrains.kotlin.util
 
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.atomic.AtomicInteger
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/AttributeArrayOwner.kt b/core/compiler.common/src/org/jetbrains/kotlin/util/AttributeArrayOwner.kt
similarity index 95%
rename from compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/AttributeArrayOwner.kt
rename to core/compiler.common/src/org/jetbrains/kotlin/util/AttributeArrayOwner.kt
index 2c9530ae228..0df3596e0b0 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/AttributeArrayOwner.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/util/AttributeArrayOwner.kt
@@ -1,9 +1,9 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 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 org.jetbrains.kotlin.fir.utils
+package org.jetbrains.kotlin.util
 
 import kotlin.reflect.KClass
 
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ComponentArrayOwner.kt b/core/compiler.common/src/org/jetbrains/kotlin/util/ComponentArrayOwner.kt
similarity index 89%
rename from compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ComponentArrayOwner.kt
rename to core/compiler.common/src/org/jetbrains/kotlin/util/ComponentArrayOwner.kt
index 26e33286940..ce857dc4c36 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ComponentArrayOwner.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/util/ComponentArrayOwner.kt
@@ -1,9 +1,9 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 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 org.jetbrains.kotlin.fir.utils
+package org.jetbrains.kotlin.util
 
 import kotlin.reflect.KClass
 
diff --git a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/WeakPair.kt b/core/compiler.common/src/org/jetbrains/kotlin/util/WeakPair.kt
similarity index 94%
rename from compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/WeakPair.kt
rename to core/compiler.common/src/org/jetbrains/kotlin/util/WeakPair.kt
index b239799f825..9fbb7d32ee1 100644
--- a/compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/WeakPair.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/util/WeakPair.kt
@@ -3,7 +3,7 @@
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-package org.jetbrains.kotlin.fir.utils
+package org.jetbrains.kotlin.util
 
 import java.lang.ref.WeakReference