diff --git a/libraries/kotlinx-metadata/jvm/ReadMe.md b/libraries/kotlinx-metadata/jvm/ReadMe.md
index 5fcfb117b75..dd8a59262fe 100644
--- a/libraries/kotlinx-metadata/jvm/ReadMe.md
+++ b/libraries/kotlinx-metadata/jvm/ReadMe.md
@@ -31,7 +31,7 @@ Let's assume we've obtained an instance of `KotlinClassMetadata.Class`; other ki
 
 ```kotlin
 metadata.accept(object : KmClassVisitor() {
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? {
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? {
         // This will be called for each function in the class. "name" is the
         // function name, and "flags" represent modifier flags (see below)
 
@@ -47,14 +47,14 @@ Please refer to [`MetadataSmokeTest.listInlineFunctions`](test/kotlinx/metadata/
 
 ## Flags
 
-Numerous `visit*` methods are declared with the parameter named `flags`. These flags represent modifiers or other boolean attributes of a declaration or a type. To check if a certain flag is present, call one of the flags in [`Flags`](../src/kotlinx/metadata/Flags.kt) on the given integer value. The set of applicable flags is documented in each `visit*` method. For example, for functions, this is common declaration flags (visibility, modality) plus `Flags.Function` flags:
+Numerous `visit*` methods take the parameter named `flags`. These flags represent modifiers or other boolean attributes of a declaration or a type. To check if a certain flag is present, call one of the flags in [`Flag`](../src/kotlinx/metadata/Flag.kt) on the given integer value. The set of applicable flags is documented in each `visit*` method. For example, for functions, this is common declaration flags (visibility, modality) plus `Flag.Function` flags:
 
 ```kotlin
-override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? {
-    if (Flags.IS_PUBLIC(flags)) {
+override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? {
+    if (Flag.IS_PUBLIC(flags)) {
         println("function $name is public")
     }
-    if (Flags.Function.IS_SUSPEND(flags)) {
+    if (Flag.Function.IS_SUSPEND(flags)) {
         println("function $name has the 'suspend' modifier")
     }
     ...
@@ -92,11 +92,11 @@ When using metadata writers from Kotlin source code, it's very convenient to use
 // Writing metadata of a class
 val header = KotlinClassMetadata.Class.Writer().run {
     // Visiting the name and the modifiers on the class.
-    // Flags are constructed by invoking "Flags(...)"
-    visit(Flags(Flags.IS_PUBLIC), "MyClass")
+    // Flags are constructed by invoking "flagsOf(...)"
+    visit(flagsOf(Flag.IS_PUBLIC), "MyClass")
     
     // Adding one public primary constructor
-    visitConstructor(Flags(Flags.IS_PUBLIC, Flags.Constructor.IS_PRIMARY))!!.run {
+    visitConstructor(flagsOf(Flag.IS_PUBLIC, Flag.Constructor.IS_PRIMARY))!!.run {
         // Visiting JVM signature (for example, to be used by kotlin-reflect)
         (visitExtensions(JvmConstructorExtensionVisitor.TYPE) as JvmConstructorExtensionVisitor).run {
             visit("<init>()V")
diff --git a/libraries/kotlinx-metadata/jvm/test/kotlinx/metadata/test/MetadataSmokeTest.kt b/libraries/kotlinx-metadata/jvm/test/kotlinx/metadata/test/MetadataSmokeTest.kt
index 58758aa6a7f..c2f0065b6b7 100644
--- a/libraries/kotlinx-metadata/jvm/test/kotlinx/metadata/test/MetadataSmokeTest.kt
+++ b/libraries/kotlinx-metadata/jvm/test/kotlinx/metadata/test/MetadataSmokeTest.kt
@@ -38,14 +38,14 @@ class MetadataSmokeTest {
 
         val klass = KotlinClassMetadata.read(L::class.java.readMetadata()) as KotlinClassMetadata.Class
         klass.accept(object : KmClassVisitor() {
-            override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? {
+            override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? {
                 return object : KmFunctionVisitor() {
                     override fun visitExtensions(type: KmExtensionType): KmFunctionExtensionVisitor? {
                         if (type != JvmFunctionExtensionVisitor.TYPE) return null
 
                         return object : JvmFunctionExtensionVisitor() {
                             override fun visit(desc: String?) {
-                                if (Flags.Function.IS_INLINE(flags) && desc != null) {
+                                if (Flag.Function.IS_INLINE(flags) && desc != null) {
                                     inlineFunctions += desc
                                 }
                             }
@@ -69,14 +69,14 @@ class MetadataSmokeTest {
         //     }
 
         val header = KotlinClassMetadata.Class.Writer().run {
-            visit(Flags(Flags.IS_PUBLIC), "Hello")
-            visitConstructor(Flags(Flags.IS_PUBLIC, Flags.Constructor.IS_PRIMARY))!!.run {
+            visit(flagsOf(Flag.IS_PUBLIC), "Hello")
+            visitConstructor(flagsOf(Flag.IS_PUBLIC, Flag.Constructor.IS_PRIMARY))!!.run {
                 (visitExtensions(JvmConstructorExtensionVisitor.TYPE) as JvmConstructorExtensionVisitor).run {
                     visit("<init>()V")
                 }
                 visitEnd()
             }
-            visitFunction(Flags(Flags.IS_PUBLIC, Flags.Function.IS_DECLARATION), "hello")!!.run {
+            visitFunction(flagsOf(Flag.IS_PUBLIC, Flag.Function.IS_DECLARATION), "hello")!!.run {
                 visitReturnType(0)!!.run {
                     visitClass("kotlin/String")
                     visitEnd()
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/Flag.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/Flag.kt
new file mode 100644
index 00000000000..45f210b0435
--- /dev/null
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/Flag.kt
@@ -0,0 +1,493 @@
+/*
+ * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlinx.metadata
+
+import org.jetbrains.kotlin.metadata.ProtoBuf.*
+import org.jetbrains.kotlin.metadata.deserialization.Flags as F
+import org.jetbrains.kotlin.metadata.ProtoBuf.Class.Kind as ClassKind
+
+/**
+ * Represents a boolean flag that is either present or not in a Kotlin declaration. A "flag" is a boolean trait that is either present
+ * or not in a declaration. To check whether the flag is present in the bitmask, call [Flag.invoke] on the flag, passing the bitmask
+ * as the argument:
+ *
+ *     override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? {
+ *         if (Flag.Function.IS_INLINE(flags)) {
+ *             ...
+ *         }
+ *     }
+ *
+ * To construct a bitmask out of several flags, call [flagsOf] on the needed flags:
+ *
+ *     v.visitFunction(flagsOf(Flag.Function.IS_DECLARATION, Flag.Function.IS_INLINE), "foo")
+ *
+ * Flag common to multiple kinds of Kotlin declarations ("common flags") are declared in [Flag.Common].
+ * Flag applicable to specific kinds of declarations ("declaration-specific flags") are declared in nested objects of the [Flag] object.
+ *
+ * Some flags are mutually exclusive, i.e. there are "flag groups" such that no more than one flag from each group can be present
+ * in the same bitmask. Among common flags, there are the following flag groups:
+ * * visibility flags: [IS_INTERNAL], [IS_PRIVATE], [IS_PROTECTED], [IS_PUBLIC], [IS_PRIVATE_TO_THIS], [IS_LOCAL]
+ * * modality flags: [IS_FINAL], [IS_OPEN], [IS_ABSTRACT], [IS_SEALED]
+ *
+ * Some declaration-specific flags form other flag groups, see the documentation of the corresponding containers for more information.
+ *
+ * @see Flags
+ * @see flagsOf
+ */
+class Flag internal constructor(
+    private val offset: Int,
+    private val bitWidth: Int,
+    private val value: Int
+) {
+    internal constructor(field: F.FlagField<*>, value: Int) : this(field.offset, field.bitWidth, value)
+
+    internal constructor(field: F.BooleanFlagField) : this(field, 1)
+
+    internal operator fun plus(flags: Flags): Flags =
+        (flags and (((1 shl bitWidth) - 1) shl offset).inv()) + (value shl offset)
+
+    /**
+     * Checks whether the flag is present in the given bitmask.
+     */
+    operator fun invoke(flags: Flags): Boolean =
+        (flags ushr offset) and ((1 shl bitWidth) - 1) == value
+
+    companion object Common {
+        /**
+         * Signifies that the corresponding declaration has at least one annotation.
+         *
+         * This flag is useful for reading Kotlin metadata on JVM efficiently. On JVM, most of the annotations are written not to the Kotlin
+         * metadata, but directly on the corresponding declarations in the class file. This flag can be used as an optimization to avoid
+         * reading annotations from the class file (which can be slow) in case when a declaration has no annotations.
+         */
+        @JvmField
+        val HAS_ANNOTATIONS = Flag(F.HAS_ANNOTATIONS)
+
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is `internal`.
+         */
+        @JvmField
+        val IS_INTERNAL = Flag(F.VISIBILITY, Visibility.INTERNAL_VALUE)
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is `private`.
+         */
+        @JvmField
+        val IS_PRIVATE = Flag(F.VISIBILITY, Visibility.PRIVATE_VALUE)
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is `protected`.
+         */
+        @JvmField
+        val IS_PROTECTED = Flag(F.VISIBILITY, Visibility.PROTECTED_VALUE)
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is `public`.
+         */
+        @JvmField
+        val IS_PUBLIC = Flag(F.VISIBILITY, Visibility.PUBLIC_VALUE)
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is "private-to-this", which is a non-denotable visibility of
+         * private members in Kotlin which are callable only on the same instance of the declaring class.
+         */
+        @JvmField
+        val IS_PRIVATE_TO_THIS = Flag(F.VISIBILITY, Visibility.PRIVATE_TO_THIS_VALUE)
+
+        /**
+         * A visibility flag, signifying that the corresponding declaration is local, i.e. declared inside a code block
+         * and not visible from the outside.
+         */
+        @JvmField
+        val IS_LOCAL = Flag(F.VISIBILITY, Visibility.LOCAL_VALUE)
+
+
+        /**
+         * A modality flag, signifying that the corresponding declaration is `final`.
+         */
+        @JvmField
+        val IS_FINAL = Flag(F.MODALITY, Modality.FINAL_VALUE)
+
+        /**
+         * A modality flag, signifying that the corresponding declaration is `open`.
+         */
+        @JvmField
+        val IS_OPEN = Flag(F.MODALITY, Modality.OPEN_VALUE)
+
+        /**
+         * A modality flag, signifying that the corresponding declaration is `abstract`.
+         */
+        @JvmField
+        val IS_ABSTRACT = Flag(F.MODALITY, Modality.ABSTRACT_VALUE)
+
+        /**
+         * A modality flag, signifying that the corresponding declaration is `sealed`.
+         */
+        @JvmField
+        val IS_SEALED = Flag(F.MODALITY, Modality.SEALED_VALUE)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin classes, including interfaces, objects, enum classes and annotation classes.
+     *
+     * In addition to the common flag groups, the following flag groups exist for class flags:
+     * * class kind flags: [IS_CLASS], [IS_INTERFACE], [IS_ENUM_CLASS], [IS_ENUM_ENTRY], [IS_ANNOTATION_CLASS], [IS_OBJECT],
+     * [IS_COMPANION_OBJECT]
+     */
+    object Class {
+        /**
+         * A class kind flag, signifying that the corresponding class is a usual `class`.
+         */
+        @JvmField
+        val IS_CLASS = Flag(F.CLASS_KIND, ClassKind.CLASS_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is an `interface`.
+         */
+        @JvmField
+        val IS_INTERFACE = Flag(F.CLASS_KIND, ClassKind.INTERFACE_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is an `enum class`.
+         */
+        @JvmField
+        val IS_ENUM_CLASS = Flag(F.CLASS_KIND, ClassKind.ENUM_CLASS_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is an enum entry.
+         */
+        @JvmField
+        val IS_ENUM_ENTRY = Flag(F.CLASS_KIND, ClassKind.ENUM_ENTRY_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is an `annotation class`.
+         */
+        @JvmField
+        val IS_ANNOTATION_CLASS = Flag(F.CLASS_KIND, ClassKind.ANNOTATION_CLASS_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is a non-companion `object`.
+         */
+        @JvmField
+        val IS_OBJECT = Flag(F.CLASS_KIND, ClassKind.OBJECT_VALUE)
+
+        /**
+         * A class kind flag, signifying that the corresponding class is a `companion object`.
+         */
+        @JvmField
+        val IS_COMPANION_OBJECT = Flag(F.CLASS_KIND, ClassKind.COMPANION_OBJECT_VALUE)
+
+
+        /**
+         * Signifies that the corresponding class is `inner`.
+         */
+        @JvmField
+        val IS_INNER = Flag(F.IS_INNER)
+
+        /**
+         * Signifies that the corresponding class is `data`.
+         */
+        @JvmField
+        val IS_DATA = Flag(F.IS_DATA)
+
+        /**
+         * Signifies that the corresponding class is `external`.
+         */
+        @JvmField
+        val IS_EXTERNAL = Flag(F.IS_EXTERNAL_CLASS)
+
+        /**
+         * Signifies that the corresponding class is `expect`.
+         */
+        @JvmField
+        val IS_EXPECT = Flag(F.IS_EXPECT_CLASS)
+
+        /**
+         * Signifies that the corresponding class is `inline`.
+         */
+        @JvmField
+        val IS_INLINE = Flag(F.IS_INLINE_CLASS)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin constructors.
+     */
+    object Constructor {
+        /**
+         * Signifies that the corresponding constructor is primary, i.e. declared in the class header, not in the class body.
+         */
+        @JvmField
+        val IS_PRIMARY = Flag(F.IS_SECONDARY, 0)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin functions.
+     *
+     * In addition to the common flag groups, the following flag groups exist for function flags:
+     * * member kind flags: [IS_DECLARATION], [IS_FAKE_OVERRIDE], [IS_DELEGATION], [IS_SYNTHESIZED]
+     */
+    object Function {
+        /**
+         * A member kind flag, signifying that the corresponding function is explicitly declared in the containing class.
+         */
+        @JvmField
+        val IS_DECLARATION = Flag(F.MEMBER_KIND, MemberKind.DECLARATION_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding function exists in the containing class because a function with a suitable
+         * signature exists in a supertype. This flag is not written by the Kotlin compiler and its effects are unspecified.
+         */
+        @JvmField
+        val IS_FAKE_OVERRIDE = Flag(F.MEMBER_KIND, MemberKind.FAKE_OVERRIDE_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding function exists in the containing class because it has been produced
+         * by interface delegation (delegation "by").
+         */
+        @JvmField
+        val IS_DELEGATION = Flag(F.MEMBER_KIND, MemberKind.DELEGATION_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding function exists in the containing class because it has been synthesized
+         * by the compiler and has no declaration in the source code.
+         */
+        @JvmField
+        val IS_SYNTHESIZED = Flag(F.MEMBER_KIND, MemberKind.SYNTHESIZED_VALUE)
+
+
+        /**
+         * Signifies that the corresponding function is `operator`.
+         */
+        @JvmField
+        val IS_OPERATOR = Flag(F.IS_OPERATOR)
+
+        /**
+         * Signifies that the corresponding function is `infix`.
+         */
+        @JvmField
+        val IS_INFIX = Flag(F.IS_INFIX)
+
+        /**
+         * Signifies that the corresponding function is `inline`.
+         */
+        @JvmField
+        val IS_INLINE = Flag(F.IS_INLINE)
+
+        /**
+         * Signifies that the corresponding function is `tailrec`.
+         */
+        @JvmField
+        val IS_TAILREC = Flag(F.IS_TAILREC)
+
+        /**
+         * Signifies that the corresponding function is `external`.
+         */
+        @JvmField
+        val IS_EXTERNAL = Flag(F.IS_EXTERNAL_FUNCTION)
+
+        /**
+         * Signifies that the corresponding function is `suspend`.
+         */
+        @JvmField
+        val IS_SUSPEND = Flag(F.IS_SUSPEND)
+
+        /**
+         * Signifies that the corresponding function is `expect`.
+         */
+        @JvmField
+        val IS_EXPECT = Flag(F.IS_EXPECT_FUNCTION)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin properties.
+     *
+     * In addition to the common flag groups, the following flag groups exist for property flags:
+     * * member kind flags: [IS_DECLARATION], [IS_FAKE_OVERRIDE], [IS_DELEGATION], [IS_SYNTHESIZED]
+     */
+    object Property {
+        /**
+         * A member kind flag, signifying that the corresponding property is explicitly declared in the containing class.
+         */
+        @JvmField
+        val IS_DECLARATION = Flag(F.MEMBER_KIND, MemberKind.DECLARATION_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding property exists in the containing class because a property with a suitable
+         * signature exists in a supertype. This flag is not written by the Kotlin compiler and its effects are unspecified.
+         */
+        @JvmField
+        val IS_FAKE_OVERRIDE = Flag(F.MEMBER_KIND, MemberKind.FAKE_OVERRIDE_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding property exists in the containing class because it has been produced
+         * by interface delegation (delegation "by").
+         */
+        @JvmField
+        val IS_DELEGATION = Flag(F.MEMBER_KIND, MemberKind.DELEGATION_VALUE)
+
+        /**
+         * A member kind flag, signifying that the corresponding property exists in the containing class because it has been synthesized
+         * by the compiler and has no declaration in the source code.
+         */
+        @JvmField
+        val IS_SYNTHESIZED = Flag(F.MEMBER_KIND, MemberKind.SYNTHESIZED_VALUE)
+
+
+        /**
+         * Signifies that the corresponding property is `var`.
+         */
+        @JvmField
+        val IS_VAR = Flag(F.IS_VAR)
+
+        /**
+         * Signifies that the corresponding property has a getter.
+         */
+        @JvmField
+        val HAS_GETTER = Flag(F.HAS_GETTER)
+
+        /**
+         * Signifies that the corresponding property has a setter.
+         */
+        @JvmField
+        val HAS_SETTER = Flag(F.HAS_SETTER)
+
+        /**
+         * Signifies that the corresponding property is `const`.
+         */
+        @JvmField
+        val IS_CONST = Flag(F.IS_CONST)
+
+        /**
+         * Signifies that the corresponding property is `lateinit`.
+         */
+        @JvmField
+        val IS_LATEINIT = Flag(F.IS_LATEINIT)
+
+        /**
+         * Signifies that the corresponding property has a constant value. On JVM, this flag allows an optimization similarly to
+         * [F.HAS_ANNOTATIONS]: constant values of properties are written to the bytecode directly, and this flag can be used to avoid
+         * reading the value from the bytecode in case there isn't one.
+         */
+        @JvmField
+        val HAS_CONSTANT = Flag(F.HAS_CONSTANT)
+
+        /**
+         * Signifies that the corresponding property is `external`.
+         */
+        @JvmField
+        val IS_EXTERNAL = Flag(F.IS_EXTERNAL_PROPERTY)
+
+        /**
+         * Signifies that the corresponding property is a delegated property.
+         */
+        @JvmField
+        val IS_DELEGATED = Flag(F.IS_DELEGATED)
+
+        /**
+         * Signifies that the corresponding property is `expect`.
+         */
+        @JvmField
+        val IS_EXPECT = Flag(F.IS_EXPECT_PROPERTY)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin property getters and setters.
+     */
+    object PropertyAccessor {
+        /**
+         * Signifies that the corresponding property accessor is not default, i.e. it has a body and/or annotations in the source code.
+         */
+        @JvmField
+        val IS_NOT_DEFAULT = Flag(F.IS_NOT_DEFAULT)
+
+        /**
+         * Signifies that the corresponding property accessor is `external`.
+         */
+        @JvmField
+        val IS_EXTERNAL = Flag(F.IS_EXTERNAL_ACCESSOR)
+
+        /**
+         * Signifies that the corresponding property accessor is `inline`.
+         */
+        @JvmField
+        val IS_INLINE = Flag(F.IS_INLINE_ACCESSOR)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin types.
+     */
+    object Type {
+        /**
+         * Signifies that the corresponding type is marked as nullable, i.e. has a question mark at the end of its notation.
+         */
+        @JvmField
+        val IS_NULLABLE = Flag(0, 1, 1)
+
+        /**
+         * Signifies that the corresponding type is `suspend`.
+         */
+        @JvmField
+        val IS_SUSPEND = Flag(F.SUSPEND_TYPE.offset + 1, F.SUSPEND_TYPE.bitWidth, 1)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin type parameters.
+     */
+    object TypeParameter {
+        /**
+         * Signifies that the corresponding type parameter is `reified`.
+         */
+        @JvmField
+        val IS_REIFIED = Flag(0, 1, 1)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin value parameters.
+     */
+    object ValueParameter {
+        /**
+         * Signifies that the corresponding value parameter declares a default value. Note that the default value itself can be a complex
+         * expression and is not available via metadata. Also note that in case of an override of a parameter with default value, the
+         * parameter in the derived method does _not_ declare the default value ([DECLARES_DEFAULT_VALUE] == false), but the parameter is
+         * still optional at the call site because the default value from the base method is used.
+         */
+        @JvmField
+        val DECLARES_DEFAULT_VALUE = Flag(F.DECLARES_DEFAULT_VALUE)
+
+        /**
+         * Signifies that the corresponding value parameter is `crossinline`.
+         */
+        @JvmField
+        val IS_CROSSINLINE = Flag(F.IS_CROSSINLINE)
+
+        /**
+         * Signifies that the corresponding value parameter is `noinline`.
+         */
+        @JvmField
+        val IS_NOINLINE = Flag(F.IS_NOINLINE)
+    }
+
+    /**
+     * A container of flags applicable to Kotlin effect expressions.
+     *
+     * Contracts are an internal feature of the standard Kotlin library, and their behavior and/or binary format
+     * may change in a subsequent release.
+     */
+    object EffectExpression {
+        /**
+         * Signifies that the corresponding effect expression should be negated to compute the proposition or the conclusion of an effect.
+         */
+        @JvmField
+        val IS_NEGATED = Flag(F.IS_NEGATED)
+
+        /**
+         * Signifies that the corresponding effect expression checks whether a value of some variable is `null`.
+         */
+        @JvmField
+        val IS_NULL_CHECK_PREDICATE = Flag(F.IS_NULL_CHECK_PREDICATE)
+    }
+}
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/Flags.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/Flags.kt
index e529dcc47e9..f7d0e2df57c 100644
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/Flags.kt
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/Flags.kt
@@ -1,481 +1,23 @@
 /*
- * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * 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/LICENSE.txt file.
  */
 
 package kotlinx.metadata
 
-import org.jetbrains.kotlin.metadata.ProtoBuf.*
-import org.jetbrains.kotlin.metadata.deserialization.Flags as F
-import org.jetbrains.kotlin.metadata.ProtoBuf.Class.Kind as ClassKind
+/**
+ * Declaration flags are represented as bitmasks of this type.
+ *
+ * @see Flag
+ */
+typealias Flags = Int
 
 /**
- * A container of all flags applicable to all Kotlin declarations. A "flag" is a boolean trait that is either present or not
- * in a declaration. To check whether the flag is present in the bitmask, call [MetadataFlag.invoke] on the flag, passing the bitmask
- * as the argument:
+ * Combines several flags into an integer bitmask.
  *
- *     override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? {
- *         if (Flags.Function.IS_INLINE(flags)) {
- *             ...
- *         }
- *     }
- *
- * To construct a bitmask out of several flags, call [Flags.invoke] on the needed flags:
- *
- *     v.visitFunction(Flags(Flags.Function.IS_DECLARATION, Flags.Function.IS_INLINE), "foo")
- *
- * Flags common to multiple kinds of Kotlin declarations ("common flags") are declared directly in the [Flags] object.
- * Flags applicable to specific kinds of declarations ("declaration-specific flags") are declared in nested objects of the [Flags] object.
- *
- * Some flags are mutually exclusive, i.e. there are "flag groups" such that no more than one flag from each group can be present
- * in the same bitmask. Among common flags, there are the following flag groups:
- * * visibility flags: [IS_INTERNAL], [IS_PRIVATE], [IS_PROTECTED], [IS_PUBLIC], [IS_PRIVATE_TO_THIS], [IS_LOCAL]
- * * modality flags: [IS_FINAL], [IS_OPEN], [IS_ABSTRACT], [IS_SEALED]
- *
- * Some declaration-specific flags form other flag groups, see the documentation of the corresponding containers for more information.
+ * Note that in case several mutually exclusive flags are passed (for example, several visibility flags), the resulting bitmask will
+ * hold the value of the latest flag. For example, `flagsOf(Flag.IS_PRIVATE, Flag.IS_PUBLIC, Flag.IS_INTERNAL)` is the same as
+ * `flagsOf(Flag.IS_INTERNAL)`.
  */
-object Flags {
-    /**
-     * Combines several flags into an integer bitmask. Note that in case several mutually exclusive flags are passed (for example,
-     * several visibility flags), the resulting bitmask will hold the value of the latest flag.
-     *
-     * For example, `Flags(Flags.IS_PRIVATE, Flags.IS_PUBLIC, Flags.IS_INTERNAL)` is the same as `Flags(Flags.IS_INTERNAL)`
-     */
-    operator fun invoke(vararg flags: MetadataFlag): Int =
-        flags.fold(0) { acc, flag -> flag + acc }
-
-    /**
-     * Signifies that the corresponding declaration has at least one annotation.
-     *
-     * This flag is useful for reading Kotlin metadata on JVM efficiently. On JVM, most of the annotations are written not to the Kotlin
-     * metadata, but directly on the corresponding declarations in the class file. This flag can be used as an optimization to avoid
-     * reading annotations from the class file (which can be slow) in case when a declaration has no annotations.
-     */
-    @JvmField
-    val HAS_ANNOTATIONS = MetadataFlag(F.HAS_ANNOTATIONS)
-
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is `internal`.
-     */
-    @JvmField
-    val IS_INTERNAL = MetadataFlag(F.VISIBILITY, Visibility.INTERNAL_VALUE)
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is `private`.
-     */
-    @JvmField
-    val IS_PRIVATE = MetadataFlag(F.VISIBILITY, Visibility.PRIVATE_VALUE)
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is `protected`.
-     */
-    @JvmField
-    val IS_PROTECTED = MetadataFlag(F.VISIBILITY, Visibility.PROTECTED_VALUE)
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is `public`.
-     */
-    @JvmField
-    val IS_PUBLIC = MetadataFlag(F.VISIBILITY, Visibility.PUBLIC_VALUE)
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is "private-to-this", which is a non-denotable visibility of
-     * private members in Kotlin which are callable only on the same instance of the declaring class.
-     */
-    @JvmField
-    val IS_PRIVATE_TO_THIS = MetadataFlag(F.VISIBILITY, Visibility.PRIVATE_TO_THIS_VALUE)
-
-    /**
-     * A visibility flag, signifying that the corresponding declaration is local, i.e. declared inside a code block
-     * and not visible from the outside.
-     */
-    @JvmField
-    val IS_LOCAL = MetadataFlag(F.VISIBILITY, Visibility.LOCAL_VALUE)
-
-
-    /**
-     * A modality flag, signifying that the corresponding declaration is `final`.
-     */
-    @JvmField
-    val IS_FINAL = MetadataFlag(F.MODALITY, Modality.FINAL_VALUE)
-
-    /**
-     * A modality flag, signifying that the corresponding declaration is `open`.
-     */
-    @JvmField
-    val IS_OPEN = MetadataFlag(F.MODALITY, Modality.OPEN_VALUE)
-
-    /**
-     * A modality flag, signifying that the corresponding declaration is `abstract`.
-     */
-    @JvmField
-    val IS_ABSTRACT = MetadataFlag(F.MODALITY, Modality.ABSTRACT_VALUE)
-
-    /**
-     * A modality flag, signifying that the corresponding declaration is `sealed`.
-     */
-    @JvmField
-    val IS_SEALED = MetadataFlag(F.MODALITY, Modality.SEALED_VALUE)
-
-
-    /**
-     * A container of flags applicable to Kotlin classes, including interfaces, objects, enum classes and annotation classes.
-     *
-     * In addition to the common flag groups, the following flag groups exist for class flags:
-     * * class kind flags: [IS_CLASS], [IS_INTERFACE], [IS_ENUM_CLASS], [IS_ENUM_ENTRY], [IS_ANNOTATION_CLASS], [IS_OBJECT],
-     * [IS_COMPANION_OBJECT]
-     */
-    object Class {
-        /**
-         * A class kind flag, signifying that the corresponding class is a usual `class`.
-         */
-        @JvmField
-        val IS_CLASS = MetadataFlag(F.CLASS_KIND, ClassKind.CLASS_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is an `interface`.
-         */
-        @JvmField
-        val IS_INTERFACE = MetadataFlag(F.CLASS_KIND, ClassKind.INTERFACE_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is an `enum class`.
-         */
-        @JvmField
-        val IS_ENUM_CLASS = MetadataFlag(F.CLASS_KIND, ClassKind.ENUM_CLASS_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is an enum entry.
-         */
-        @JvmField
-        val IS_ENUM_ENTRY = MetadataFlag(F.CLASS_KIND, ClassKind.ENUM_ENTRY_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is an `annotation class`.
-         */
-        @JvmField
-        val IS_ANNOTATION_CLASS = MetadataFlag(F.CLASS_KIND, ClassKind.ANNOTATION_CLASS_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is a non-companion `object`.
-         */
-        @JvmField
-        val IS_OBJECT = MetadataFlag(F.CLASS_KIND, ClassKind.OBJECT_VALUE)
-
-        /**
-         * A class kind flag, signifying that the corresponding class is a `companion object`.
-         */
-        @JvmField
-        val IS_COMPANION_OBJECT = MetadataFlag(F.CLASS_KIND, ClassKind.COMPANION_OBJECT_VALUE)
-
-
-        /**
-         * Signifies that the corresponding class is `inner`.
-         */
-        @JvmField
-        val IS_INNER = MetadataFlag(F.IS_INNER)
-
-        /**
-         * Signifies that the corresponding class is `data`.
-         */
-        @JvmField
-        val IS_DATA = MetadataFlag(F.IS_DATA)
-
-        /**
-         * Signifies that the corresponding class is `external`.
-         */
-        @JvmField
-        val IS_EXTERNAL = MetadataFlag(F.IS_EXTERNAL_CLASS)
-
-        /**
-         * Signifies that the corresponding class is `expect`.
-         */
-        @JvmField
-        val IS_EXPECT = MetadataFlag(F.IS_EXPECT_CLASS)
-
-        /**
-         * Signifies that the corresponding class is `inline`.
-         */
-        @JvmField
-        val IS_INLINE = MetadataFlag(F.IS_INLINE_CLASS)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin constructors.
-     */
-    object Constructor {
-        /**
-         * Signifies that the corresponding constructor is primary, i.e. declared in the class header, not in the class body.
-         */
-        @JvmField
-        val IS_PRIMARY = MetadataFlag(F.IS_SECONDARY, 0)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin functions.
-     *
-     * In addition to the common flag groups, the following flag groups exist for function flags:
-     * * member kind flags: [IS_DECLARATION], [IS_FAKE_OVERRIDE], [IS_DELEGATION], [IS_SYNTHESIZED]
-     */
-    object Function {
-        /**
-         * A member kind flag, signifying that the corresponding function is explicitly declared in the containing class.
-         */
-        @JvmField
-        val IS_DECLARATION = MetadataFlag(F.MEMBER_KIND, MemberKind.DECLARATION_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding function exists in the containing class because a function with a suitable
-         * signature exists in a supertype. This flag is not written by the Kotlin compiler and its effects are unspecified.
-         */
-        @JvmField
-        val IS_FAKE_OVERRIDE = MetadataFlag(F.MEMBER_KIND, MemberKind.FAKE_OVERRIDE_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding function exists in the containing class because it has been produced
-         * by interface delegation (delegation "by").
-         */
-        @JvmField
-        val IS_DELEGATION = MetadataFlag(F.MEMBER_KIND, MemberKind.DELEGATION_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding function exists in the containing class because it has been synthesized
-         * by the compiler and has no declaration in the source code.
-         */
-        @JvmField
-        val IS_SYNTHESIZED = MetadataFlag(F.MEMBER_KIND, MemberKind.SYNTHESIZED_VALUE)
-
-
-        /**
-         * Signifies that the corresponding function is `operator`.
-         */
-        @JvmField
-        val IS_OPERATOR = MetadataFlag(F.IS_OPERATOR)
-
-        /**
-         * Signifies that the corresponding function is `infix`.
-         */
-        @JvmField
-        val IS_INFIX = MetadataFlag(F.IS_INFIX)
-
-        /**
-         * Signifies that the corresponding function is `inline`.
-         */
-        @JvmField
-        val IS_INLINE = MetadataFlag(F.IS_INLINE)
-
-        /**
-         * Signifies that the corresponding function is `tailrec`.
-         */
-        @JvmField
-        val IS_TAILREC = MetadataFlag(F.IS_TAILREC)
-
-        /**
-         * Signifies that the corresponding function is `external`.
-         */
-        @JvmField
-        val IS_EXTERNAL = MetadataFlag(F.IS_EXTERNAL_FUNCTION)
-
-        /**
-         * Signifies that the corresponding function is `suspend`.
-         */
-        @JvmField
-        val IS_SUSPEND = MetadataFlag(F.IS_SUSPEND)
-
-        /**
-         * Signifies that the corresponding function is `expect`.
-         */
-        @JvmField
-        val IS_EXPECT = MetadataFlag(F.IS_EXPECT_FUNCTION)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin properties.
-     *
-     * In addition to the common flag groups, the following flag groups exist for property flags:
-     * * member kind flags: [IS_DECLARATION], [IS_FAKE_OVERRIDE], [IS_DELEGATION], [IS_SYNTHESIZED]
-     */
-    object Property {
-        /**
-         * A member kind flag, signifying that the corresponding property is explicitly declared in the containing class.
-         */
-        @JvmField
-        val IS_DECLARATION = MetadataFlag(F.MEMBER_KIND, MemberKind.DECLARATION_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding property exists in the containing class because a property with a suitable
-         * signature exists in a supertype. This flag is not written by the Kotlin compiler and its effects are unspecified.
-         */
-        @JvmField
-        val IS_FAKE_OVERRIDE = MetadataFlag(F.MEMBER_KIND, MemberKind.FAKE_OVERRIDE_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding property exists in the containing class because it has been produced
-         * by interface delegation (delegation "by").
-         */
-        @JvmField
-        val IS_DELEGATION = MetadataFlag(F.MEMBER_KIND, MemberKind.DELEGATION_VALUE)
-
-        /**
-         * A member kind flag, signifying that the corresponding property exists in the containing class because it has been synthesized
-         * by the compiler and has no declaration in the source code.
-         */
-        @JvmField
-        val IS_SYNTHESIZED = MetadataFlag(F.MEMBER_KIND, MemberKind.SYNTHESIZED_VALUE)
-
-
-        /**
-         * Signifies that the corresponding property is `var`.
-         */
-        @JvmField
-        val IS_VAR = MetadataFlag(F.IS_VAR)
-
-        /**
-         * Signifies that the corresponding property has a getter.
-         */
-        @JvmField
-        val HAS_GETTER = MetadataFlag(F.HAS_GETTER)
-
-        /**
-         * Signifies that the corresponding property has a setter.
-         */
-        @JvmField
-        val HAS_SETTER = MetadataFlag(F.HAS_SETTER)
-
-        /**
-         * Signifies that the corresponding property is `const`.
-         */
-        @JvmField
-        val IS_CONST = MetadataFlag(F.IS_CONST)
-
-        /**
-         * Signifies that the corresponding property is `lateinit`.
-         */
-        @JvmField
-        val IS_LATEINIT = MetadataFlag(F.IS_LATEINIT)
-
-        /**
-         * Signifies that the corresponding property has a constant value. On JVM, this flag allows an optimization similarly to
-         * [F.HAS_ANNOTATIONS]: constant values of properties are written to the bytecode directly, and this flag can be used to avoid
-         * reading the value from the bytecode in case there isn't one.
-         */
-        @JvmField
-        val HAS_CONSTANT = MetadataFlag(F.HAS_CONSTANT)
-
-        /**
-         * Signifies that the corresponding property is `external`.
-         */
-        @JvmField
-        val IS_EXTERNAL = MetadataFlag(F.IS_EXTERNAL_PROPERTY)
-
-        /**
-         * Signifies that the corresponding property is a delegated property.
-         */
-        @JvmField
-        val IS_DELEGATED = MetadataFlag(F.IS_DELEGATED)
-
-        /**
-         * Signifies that the corresponding property is `expect`.
-         */
-        @JvmField
-        val IS_EXPECT = MetadataFlag(F.IS_EXPECT_PROPERTY)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin property getters and setters.
-     */
-    object PropertyAccessor {
-        /**
-         * Signifies that the corresponding property accessor is not default, i.e. it has a body and/or annotations in the source code.
-         */
-        @JvmField
-        val IS_NOT_DEFAULT = MetadataFlag(F.IS_NOT_DEFAULT)
-
-        /**
-         * Signifies that the corresponding property accessor is `external`.
-         */
-        @JvmField
-        val IS_EXTERNAL = MetadataFlag(F.IS_EXTERNAL_ACCESSOR)
-
-        /**
-         * Signifies that the corresponding property accessor is `inline`.
-         */
-        @JvmField
-        val IS_INLINE = MetadataFlag(F.IS_INLINE_ACCESSOR)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin types.
-     */
-    object Type {
-        /**
-         * Signifies that the corresponding type is marked as nullable, i.e. has a question mark at the end of its notation.
-         */
-        @JvmField
-        val IS_NULLABLE = MetadataFlag(0, 1, 1)
-
-        /**
-         * Signifies that the corresponding type is `suspend`.
-         */
-        @JvmField
-        val IS_SUSPEND = MetadataFlag(F.SUSPEND_TYPE.offset + 1, F.SUSPEND_TYPE.bitWidth, 1)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin type parameters.
-     */
-    object TypeParameter {
-        /**
-         * Signifies that the corresponding type parameter is `reified`.
-         */
-        @JvmField
-        val IS_REIFIED = MetadataFlag(0, 1, 1)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin value parameters.
-     */
-    object ValueParameter {
-        /**
-         * Signifies that the corresponding value parameter declares a default value. Note that the default value itself can be a complex
-         * expression and is not available via metadata. Also note that in case of an override of a parameter with default value, the
-         * parameter in the derived method does _not_ declare the default value ([DECLARES_DEFAULT_VALUE] == false), but the parameter is
-         * still optional at the call site because the default value from the base method is used.
-         */
-        @JvmField
-        val DECLARES_DEFAULT_VALUE = MetadataFlag(F.DECLARES_DEFAULT_VALUE)
-
-        /**
-         * Signifies that the corresponding value parameter is `crossinline`.
-         */
-        @JvmField
-        val IS_CROSSINLINE = MetadataFlag(F.IS_CROSSINLINE)
-
-        /**
-         * Signifies that the corresponding value parameter is `noinline`.
-         */
-        @JvmField
-        val IS_NOINLINE = MetadataFlag(F.IS_NOINLINE)
-    }
-
-    /**
-     * A container of flags applicable to Kotlin effect expressions.
-     *
-     * Contracts are an internal feature of the standard Kotlin library, and their behavior and/or binary format
-     * may change in a subsequent release.
-     */
-    object EffectExpression {
-        /**
-         * Signifies that the corresponding effect expression should be negated to compute the proposition or the conclusion of an effect.
-         */
-        @JvmField
-        val IS_NEGATED = MetadataFlag(F.IS_NEGATED)
-
-        /**
-         * Signifies that the corresponding effect expression checks whether a value of some variable is `null`.
-         */
-        @JvmField
-        val IS_NULL_CHECK_PREDICATE = MetadataFlag(F.IS_NULL_CHECK_PREDICATE)
-    }
-}
+fun flagsOf(vararg flags: Flag): Flags =
+    flags.fold(0) { acc, flag -> flag + acc }
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/MetadataFlag.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/MetadataFlag.kt
deleted file mode 100644
index 782ed012988..00000000000
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/MetadataFlag.kt
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
- * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
- */
-
-package kotlinx.metadata
-
-import org.jetbrains.kotlin.metadata.deserialization.Flags.BooleanFlagField
-import org.jetbrains.kotlin.metadata.deserialization.Flags.FlagField
-
-/**
- * Represents a boolean flag that is either present or not in a Kotlin declaration.
- *
- * @see Flags
- */
-class MetadataFlag internal constructor(
-    private val offset: Int,
-    private val bitWidth: Int,
-    private val value: Int
-) {
-    internal constructor(field: FlagField<*>, value: Int) : this(field.offset, field.bitWidth, value)
-
-    internal constructor(field: BooleanFlagField) : this(field, 1)
-
-    internal operator fun plus(flags: Int): Int =
-        (flags and (((1 shl bitWidth) - 1) shl offset).inv()) + (value shl offset)
-
-    /**
-     * Checks whether the flag is present in the given bitmask.
-     */
-    operator fun invoke(flags: Int): Boolean =
-        (flags ushr offset) and ((1 shl bitWidth) - 1) == value
-}
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/annotations.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/annotations.kt
index e0147cf4619..80b2f5788ff 100644
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/annotations.kt
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/annotations.kt
@@ -8,7 +8,7 @@ package kotlinx.metadata
 /**
  * Represents an annotation, written to the Kotlin metadata. Note that not all annotations are written to metadata on all platforms.
  * For example, on JVM most of the annotations are written directly on the corresponding declarations in the class file,
- * and entries in the metadata only have a flag ([Flags.HAS_ANNOTATIONS]) to signal if they do have annotations in the bytecode.
+ * and entries in the metadata only have a flag ([Flag.HAS_ANNOTATIONS]) to signal if they do have annotations in the bytecode.
  * On JVM, only annotations on type parameters and types are serialized to the Kotlin metadata.
  *
  * @param className the fully qualified name of the annotation class
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/readers.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/readers.kt
index aeb80e7c398..6796a36e764 100644
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/readers.kt
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/readers.kt
@@ -9,8 +9,8 @@ import kotlinx.metadata.*
 import kotlinx.metadata.impl.extensions.MetadataExtensions
 import org.jetbrains.kotlin.metadata.ProtoBuf
 import org.jetbrains.kotlin.metadata.deserialization.*
-import org.jetbrains.kotlin.metadata.deserialization.Flags
 import org.jetbrains.kotlin.protobuf.MessageLite
+import org.jetbrains.kotlin.metadata.deserialization.Flags as F
 
 class ReadContext(
     internal val strings: NameResolver,
@@ -104,8 +104,8 @@ private fun KmDeclarationContainerVisitor.visitDeclarations(
 
     for (property in properties) {
         val flags = property.flags
-        val defaultAccessorFlags = Flags.getAccessorFlags(
-            Flags.HAS_ANNOTATIONS.get(flags), Flags.VISIBILITY.get(flags), Flags.MODALITY.get(flags), false, false, false
+        val defaultAccessorFlags = F.getAccessorFlags(
+            F.HAS_ANNOTATIONS.get(flags), F.VISIBILITY.get(flags), F.MODALITY.get(flags), false, false, false
         )
         visitProperty(
             flags,
@@ -242,7 +242,7 @@ private fun ProtoBuf.ValueParameter.accept(v: KmValueParameterVisitor, c: ReadCo
 }
 
 private inline fun ProtoBuf.TypeParameter.accept(
-    visit: (flags: Int, name: String, id: Int, variance: KmVariance) -> KmTypeParameterVisitor?,
+    visit: (flags: Flags, name: String, id: Int, variance: KmVariance) -> KmTypeParameterVisitor?,
     c: ReadContext
 ) {
     val variance = when (variance!!) {
@@ -405,9 +405,9 @@ private fun ProtoBuf.Expression.accept(v: KmEffectExpressionVisitor, c: ReadCont
     v.visitEnd()
 }
 
-private val ProtoBuf.Type.typeFlags: Int
+private val ProtoBuf.Type.typeFlags: Flags
     get() = (if (nullable) 1 shl 0 else 0) +
             (flags shl 1)
 
-private val ProtoBuf.TypeParameter.typeParameterFlags: Int
+private val ProtoBuf.TypeParameter.typeParameterFlags: Flags
     get() = if (reified) 1 else 0
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/writers.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/writers.kt
index 199ba54726f..b48482ca233 100644
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/writers.kt
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/impl/writers.kt
@@ -25,13 +25,13 @@ class WriteContext {
 }
 
 private fun writeTypeParameter(
-    c: WriteContext, flags: Int, name: String, id: Int, variance: KmVariance,
+    c: WriteContext, flags: Flags, name: String, id: Int, variance: KmVariance,
     output: (ProtoBuf.TypeParameter.Builder) -> Unit
 ): KmTypeParameterVisitor =
     object : KmTypeParameterVisitor() {
         private val t = ProtoBuf.TypeParameter.newBuilder()
 
-        override fun visitUpperBound(flags: Int): KmTypeVisitor? =
+        override fun visitUpperBound(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.addUpperBound(it) }
 
         override fun visitExtensions(type: KmExtensionType): KmTypeParameterExtensionVisitor? =
@@ -40,7 +40,7 @@ private fun writeTypeParameter(
         override fun visitEnd() {
             t.name = c[name]
             t.id = id
-            val reified = Flags.TypeParameter.IS_REIFIED(flags)
+            val reified = Flag.TypeParameter.IS_REIFIED(flags)
             if (reified != ProtoBuf.TypeParameter.getDefaultInstance().reified) {
                 t.reified = reified
             }
@@ -53,7 +53,7 @@ private fun writeTypeParameter(
         }
     }
 
-private fun writeType(c: WriteContext, flags: Int, output: (ProtoBuf.Type.Builder) -> Unit): KmTypeVisitor =
+private fun writeType(c: WriteContext, flags: Flags, output: (ProtoBuf.Type.Builder) -> Unit): KmTypeVisitor =
     object : KmTypeVisitor() {
         private val t = ProtoBuf.Type.newBuilder()
 
@@ -71,7 +71,7 @@ private fun writeType(c: WriteContext, flags: Int, output: (ProtoBuf.Type.Builde
             })
         }
 
-        override fun visitArgument(flags: Int, variance: KmVariance): KmTypeVisitor? =
+        override fun visitArgument(flags: Flags, variance: KmVariance): KmTypeVisitor? =
             writeType(c, flags) { argument ->
                 t.addArgument(ProtoBuf.Type.Argument.newBuilder().apply {
                     if (variance == KmVariance.IN) {
@@ -87,13 +87,13 @@ private fun writeType(c: WriteContext, flags: Int, output: (ProtoBuf.Type.Builde
             t.typeParameter = id
         }
 
-        override fun visitAbbreviatedType(flags: Int): KmTypeVisitor? =
+        override fun visitAbbreviatedType(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.abbreviatedType = it.build() }
 
-        override fun visitOuterType(flags: Int): KmTypeVisitor? =
+        override fun visitOuterType(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.outerType = it.build() }
 
-        override fun visitFlexibleTypeUpperBound(flags: Int, typeFlexibilityId: String?): KmTypeVisitor? =
+        override fun visitFlexibleTypeUpperBound(flags: Flags, typeFlexibilityId: String?): KmTypeVisitor? =
             writeType(c, flags) {
                 if (typeFlexibilityId != null) {
                     t.flexibleTypeCapabilitiesId = c[typeFlexibilityId]
@@ -105,7 +105,7 @@ private fun writeType(c: WriteContext, flags: Int, output: (ProtoBuf.Type.Builde
             c.extensions.writeTypeExtensions(type, t, c.strings)
 
         override fun visitEnd() {
-            if (Flags.Type.IS_NULLABLE(flags)) {
+            if (Flag.Type.IS_NULLABLE(flags)) {
                 t.nullable = true
             }
             val flagsToWrite = flags shr 1
@@ -116,11 +116,11 @@ private fun writeType(c: WriteContext, flags: Int, output: (ProtoBuf.Type.Builde
         }
     }
 
-private fun writeConstructor(c: WriteContext, flags: Int, output: (ProtoBuf.Constructor.Builder) -> Unit): KmConstructorVisitor =
+private fun writeConstructor(c: WriteContext, flags: Flags, output: (ProtoBuf.Constructor.Builder) -> Unit): KmConstructorVisitor =
     object : KmConstructorVisitor() {
         val t = ProtoBuf.Constructor.newBuilder()
 
-        override fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+        override fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
             writeValueParameter(c, flags, name) { t.addValueParameter(it.build()) }
 
         override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -137,20 +137,20 @@ private fun writeConstructor(c: WriteContext, flags: Int, output: (ProtoBuf.Cons
         }
     }
 
-private fun writeFunction(c: WriteContext, flags: Int, name: String, output: (ProtoBuf.Function.Builder) -> Unit): KmFunctionVisitor =
+private fun writeFunction(c: WriteContext, flags: Flags, name: String, output: (ProtoBuf.Function.Builder) -> Unit): KmFunctionVisitor =
     object : KmFunctionVisitor() {
         val t = ProtoBuf.Function.newBuilder()
 
-        override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+        override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
             writeTypeParameter(c, flags, name, id, variance) { t.addTypeParameter(it) }
 
-        override fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+        override fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.receiverType = it.build() }
 
-        override fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+        override fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
             writeValueParameter(c, flags, name) { t.addValueParameter(it) }
 
-        override fun visitReturnType(flags: Int): KmTypeVisitor? =
+        override fun visitReturnType(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.returnType = it.build() }
 
         override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -172,20 +172,20 @@ private fun writeFunction(c: WriteContext, flags: Int, name: String, output: (Pr
     }
 
 private fun writeProperty(
-    c: WriteContext, flags: Int, name: String, getterFlags: Int, setterFlags: Int, output: (ProtoBuf.Property.Builder) -> Unit
+    c: WriteContext, flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags, output: (ProtoBuf.Property.Builder) -> Unit
 ): KmPropertyVisitor = object : KmPropertyVisitor() {
     val t = ProtoBuf.Property.newBuilder()
 
-    override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         writeTypeParameter(c, flags, name, id, variance) { t.addTypeParameter(it) }
 
-    override fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+    override fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.receiverType = it.build() }
 
-    override fun visitSetterParameter(flags: Int, name: String): KmValueParameterVisitor? =
+    override fun visitSetterParameter(flags: Flags, name: String): KmValueParameterVisitor? =
         writeValueParameter(c, flags, name) { t.setterValueParameter = it.build() }
 
-    override fun visitReturnType(flags: Int): KmTypeVisitor? =
+    override fun visitReturnType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.returnType = it.build() }
 
     override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -207,15 +207,15 @@ private fun writeProperty(
 }
 
 private fun writeValueParameter(
-    c: WriteContext, flags: Int, name: String,
+    c: WriteContext, flags: Flags, name: String,
     output: (ProtoBuf.ValueParameter.Builder) -> Unit
 ): KmValueParameterVisitor = object : KmValueParameterVisitor() {
     val t = ProtoBuf.ValueParameter.newBuilder()
 
-    override fun visitType(flags: Int): KmTypeVisitor? =
+    override fun visitType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.type = it.build() }
 
-    override fun visitVarargElementType(flags: Int): KmTypeVisitor? =
+    override fun visitVarargElementType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.varargElementType = it.build() }
 
     override fun visitEnd() {
@@ -228,18 +228,18 @@ private fun writeValueParameter(
 }
 
 private fun writeTypeAlias(
-    c: WriteContext, flags: Int, name: String,
+    c: WriteContext, flags: Flags, name: String,
     output: (ProtoBuf.TypeAlias.Builder) -> Unit
 ): KmTypeAliasVisitor = object : KmTypeAliasVisitor() {
     val t = ProtoBuf.TypeAlias.newBuilder()
 
-    override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         writeTypeParameter(c, flags, name, id, variance) { t.addTypeParameter(it) }
 
-    override fun visitUnderlyingType(flags: Int): KmTypeVisitor? =
+    override fun visitUnderlyingType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.underlyingType = it.build() }
 
-    override fun visitExpandedType(flags: Int): KmTypeVisitor? =
+    override fun visitExpandedType(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.expandedType = it.build() }
 
     override fun visitAnnotation(annotation: KmAnnotation) {
@@ -351,7 +351,7 @@ private fun writeEffectExpression(c: WriteContext, output: (ProtoBuf.Expression.
     object : KmEffectExpressionVisitor() {
         val t = ProtoBuf.Expression.newBuilder()
 
-        override fun visit(flags: Int, parameterIndex: Int?) {
+        override fun visit(flags: Flags, parameterIndex: Int?) {
             if (flags != ProtoBuf.Expression.getDefaultInstance().flags) {
                 t.flags = flags
             }
@@ -370,7 +370,7 @@ private fun writeEffectExpression(c: WriteContext, output: (ProtoBuf.Expression.
             }
         }
 
-        override fun visitIsInstanceType(flags: Int): KmTypeVisitor? =
+        override fun visitIsInstanceType(flags: Flags): KmTypeVisitor? =
             writeType(c, flags) { t.isInstanceType = it.build() }
 
         override fun visitAndArgument(): KmEffectExpressionVisitor? =
@@ -388,29 +388,29 @@ open class ClassWriter : KmClassVisitor() {
     val t = ProtoBuf.Class.newBuilder()!!
     val c = WriteContext()
 
-    override fun visit(flags: Int, name: ClassName) {
+    override fun visit(flags: Flags, name: ClassName) {
         if (flags != ProtoBuf.Class.getDefaultInstance().flags) {
             t.flags = flags
         }
         t.fqName = c.getClassName(name)
     }
 
-    override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         writeTypeParameter(c, flags, name, id, variance) { t.addTypeParameter(it) }
 
-    override fun visitSupertype(flags: Int): KmTypeVisitor? =
+    override fun visitSupertype(flags: Flags): KmTypeVisitor? =
         writeType(c, flags) { t.addSupertype(it) }
 
-    override fun visitConstructor(flags: Int): KmConstructorVisitor? =
+    override fun visitConstructor(flags: Flags): KmConstructorVisitor? =
         writeConstructor(c, flags) { t.addConstructor(it) }
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         writeFunction(c, flags, name) { t.addFunction(it) }
 
-    override fun visitProperty(flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor? =
+    override fun visitProperty(flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor? =
         writeProperty(c, flags, name, getterFlags, setterFlags) { t.addProperty(it) }
 
-    override fun visitTypeAlias(flags: Int, name: String): KmTypeAliasVisitor? =
+    override fun visitTypeAlias(flags: Flags, name: String): KmTypeAliasVisitor? =
         writeTypeAlias(c, flags, name) { t.addTypeAlias(it) }
 
     override fun visitCompanionObject(name: String) {
@@ -445,13 +445,13 @@ open class PackageWriter : KmPackageVisitor() {
     val t = ProtoBuf.Package.newBuilder()!!
     val c = WriteContext()
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         writeFunction(c, flags, name) { t.addFunction(it) }
 
-    override fun visitProperty(flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor? =
+    override fun visitProperty(flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor? =
         writeProperty(c, flags, name, getterFlags, setterFlags) { t.addProperty(it) }
 
-    override fun visitTypeAlias(flags: Int, name: String): KmTypeAliasVisitor? =
+    override fun visitTypeAlias(flags: Flags, name: String): KmTypeAliasVisitor? =
         writeTypeAlias(c, flags, name) { t.addTypeAlias(it) }
 
     override fun visitEnd() {
@@ -465,6 +465,6 @@ open class LambdaWriter : KmLambdaVisitor() {
     var t: ProtoBuf.Function.Builder? = null
     val c = WriteContext()
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         writeFunction(c, flags, name) { t = it }
 }
diff --git a/libraries/kotlinx-metadata/src/kotlinx/metadata/visitors.kt b/libraries/kotlinx-metadata/src/kotlinx/metadata/visitors.kt
index 0d0e8e85aaf..309a872e47b 100644
--- a/libraries/kotlinx-metadata/src/kotlinx/metadata/visitors.kt
+++ b/libraries/kotlinx-metadata/src/kotlinx/metadata/visitors.kt
@@ -12,32 +12,32 @@ abstract class KmDeclarationContainerVisitor @JvmOverloads constructor(protected
     /**
      * Visits a function in the container.
      *
-     * @param flags function flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag and [Flags.Function] flags
+     * @param flags function flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag and [Flag.Function] flags
      * @param name the name of the function
      */
-    open fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    open fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         delegate?.visitFunction(flags, name)
 
     /**
      * Visits a property in the container.
      *
-     * @param flags property flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag and [Flags.Property] flags
+     * @param flags property flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag and [Flag.Property] flags
      * @param name the name of the property
-     * @param getterFlags property accessor flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag
-     *                    and [Flags.PropertyAccessor] flags
-     * @param setterFlags property accessor flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag
-     *                    and [Flags.PropertyAccessor] flags
+     * @param getterFlags property accessor flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag
+     *   and [Flag.PropertyAccessor] flags
+     * @param setterFlags property accessor flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag
+     *   and [Flag.PropertyAccessor] flags
      */
-    open fun visitProperty(flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor? =
+    open fun visitProperty(flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor? =
         delegate?.visitProperty(flags, name, getterFlags, setterFlags)
 
     /**
      * Visits a type alias in the container.
      *
-     * @param flags type alias flags, consisting of [Flags.HAS_ANNOTATIONS] and visibility flag
+     * @param flags type alias flags, consisting of [Flag.HAS_ANNOTATIONS] and visibility flag
      * @param name the name of the type alias
      */
-    open fun visitTypeAlias(flags: Int, name: String): KmTypeAliasVisitor? =
+    open fun visitTypeAlias(flags: Flags, name: String): KmTypeAliasVisitor? =
         delegate?.visitTypeAlias(flags, name)
 }
 
@@ -54,39 +54,39 @@ abstract class KmClassVisitor @JvmOverloads constructor(delegate: KmClassVisitor
     /**
      * Visits the basic information about the class.
      *
-     * @param flags class flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag and [Flags.Class] flags
+     * @param flags class flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag and [Flag.Class] flags
      * @param name the name of the class
      */
-    open fun visit(flags: Int, name: ClassName) {
+    open fun visit(flags: Flags, name: ClassName) {
         delegate?.visit(flags, name)
     }
 
     /**
      * Visits a type parameter of the class.
      *
-     * @param flags type parameter flags, consisting of [Flags.TypeParameter] flags
+     * @param flags type parameter flags, consisting of [Flag.TypeParameter] flags
      * @param name the name of the type parameter
      * @param id the id of the type parameter, useful to be able to uniquely identify the type parameter in different contexts where
      *           the name isn't enough (e.g. `class A<T> { fun <T> foo(t: T) }`)
      * @param variance the declaration-site variance of the type parameter
      */
-    open fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    open fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         delegate?.visitTypeParameter(flags, name, id, variance)
 
     /**
      * Visits a supertype of the class.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitSupertype(flags: Int): KmTypeVisitor? =
+    open fun visitSupertype(flags: Flags): KmTypeVisitor? =
         delegate?.visitSupertype(flags)
 
     /**
      * Visits a constructor of the class.
      *
-     * @param flags constructor flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag and [Flags.Constructor] flags
+     * @param flags constructor flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag and [Flag.Constructor] flags
      */
-    open fun visitConstructor(flags: Int): KmConstructorVisitor? =
+    open fun visitConstructor(flags: Flags): KmConstructorVisitor? =
         delegate?.visitConstructor(flags)
 
     /**
@@ -165,10 +165,10 @@ abstract class KmLambdaVisitor @JvmOverloads constructor(private val delegate: K
     /**
      * Visits the signature of a synthetic anonymous function, representing the lambda.
      *
-     * @param flags function flags, consisting of [Flags.HAS_ANNOTATIONS], visibility flag, modality flag and [Flags.Function] flags
+     * @param flags function flags, consisting of [Flag.HAS_ANNOTATIONS], visibility flag, modality flag and [Flag.Function] flags
      * @param name the name of the function (usually `"<anonymous>"` or `"<no name provided>"` for lambdas emitted by the Kotlin compiler)
      */
-    open fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    open fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         delegate?.visitFunction(flags, name)
 
     /**
@@ -188,10 +188,10 @@ abstract class KmConstructorVisitor @JvmOverloads constructor(private val delega
     /**
      * Visits a value parameter of the constructor.
      *
-     * @param flags value parameter flags, consisting of [Flags.ValueParameter] flags
+     * @param flags value parameter flags, consisting of [Flag.ValueParameter] flags
      * @param name the name of the value parameter
      */
-    open fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+    open fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
         delegate?.visitValueParameter(flags, name)
 
     /**
@@ -226,38 +226,38 @@ abstract class KmFunctionVisitor @JvmOverloads constructor(private val delegate:
     /**
      * Visits a type parameter of the function.
      *
-     * @param flags type parameter flags, consisting of [Flags.TypeParameter] flags
+     * @param flags type parameter flags, consisting of [Flag.TypeParameter] flags
      * @param name the name of the type parameter
      * @param id the id of the type parameter, useful to be able to uniquely identify the type parameter in different contexts where
      *           the name isn't enough (e.g. `class A<T> { fun <T> foo(t: T) }`)
      * @param variance the declaration-site variance of the type parameter
      */
-    open fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    open fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         delegate?.visitTypeParameter(flags, name, id, variance)
 
     /**
      * Visits the type of the receiver of the function, if this is an extension function.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+    open fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
         delegate?.visitReceiverParameterType(flags)
 
     /**
      * Visits a value parameter of the function.
      *
-     * @param flags value parameter flags, consisting of [Flags.ValueParameter] flags
+     * @param flags value parameter flags, consisting of [Flag.ValueParameter] flags
      * @param name the name of the value parameter
      */
-    open fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+    open fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
         delegate?.visitValueParameter(flags, name)
 
     /**
      * Visits the return type of the function.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitReturnType(flags: Int): KmTypeVisitor? =
+    open fun visitReturnType(flags: Flags): KmTypeVisitor? =
         delegate?.visitReturnType(flags)
 
     /**
@@ -298,38 +298,38 @@ abstract class KmPropertyVisitor @JvmOverloads constructor(private val delegate:
     /**
      * Visits a type parameter of the property.
      *
-     * @param flags type parameter flags, consisting of [Flags.TypeParameter] flags
+     * @param flags type parameter flags, consisting of [Flag.TypeParameter] flags
      * @param name the name of the type parameter
      * @param id the id of the type parameter, useful to be able to uniquely identify the type parameter in different contexts where
      *           the name isn't enough (e.g. `class A<T> { fun <T> foo(t: T) }`)
      * @param variance the declaration-site variance of the type parameter
      */
-    open fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    open fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         delegate?.visitTypeParameter(flags, name, id, variance)
 
     /**
      * Visits the type of the receiver of the property, if this is an extension property.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+    open fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
         delegate?.visitReceiverParameterType(flags)
 
     /**
      * Visits a value parameter of the setter of this property, if this is a `var` property.
      *
-     * @param flags value parameter flags, consisting of [Flags.ValueParameter] flags
+     * @param flags value parameter flags, consisting of [Flag.ValueParameter] flags
      * @param name the name of the value parameter (`"<set-?>"` for properties emitted by the Kotlin compiler)
      */
-    open fun visitSetterParameter(flags: Int, name: String): KmValueParameterVisitor? =
+    open fun visitSetterParameter(flags: Flags, name: String): KmValueParameterVisitor? =
         delegate?.visitSetterParameter(flags, name)
 
     /**
      * Visits the type of the property.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitReturnType(flags: Int): KmTypeVisitor? =
+    open fun visitReturnType(flags: Flags): KmTypeVisitor? =
         delegate?.visitReturnType(flags)
 
     /**
@@ -364,30 +364,30 @@ abstract class KmTypeAliasVisitor @JvmOverloads constructor(private val delegate
     /**
      * Visits a type parameter of the type alias.
      *
-     * @param flags type parameter flags, consisting of [Flags.TypeParameter] flags
+     * @param flags type parameter flags, consisting of [Flag.TypeParameter] flags
      * @param name the name of the type parameter
      * @param id the id of the type parameter, useful to be able to uniquely identify the type parameter in different contexts where
      *           the name isn't enough (e.g. `class A<T> { fun <T> foo(t: T) }`)
      * @param variance the declaration-site variance of the type parameter
      */
-    open fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    open fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         delegate?.visitTypeParameter(flags, name, id, variance)
 
     /**
      * Visits the underlying type of the type alias, i.e. the type in the right-hand side of the type alias declaration.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitUnderlyingType(flags: Int): KmTypeVisitor? =
+    open fun visitUnderlyingType(flags: Flags): KmTypeVisitor? =
         delegate?.visitUnderlyingType(flags)
 
     /**
      * Visits the expanded type of the type alias, i.e. the full expansion of the underlying type, where all type aliases are substituted
      * with their expanded types. If not type aliases are used in the underlying type, expanded type is equal to the underlying type.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitExpandedType(flags: Int): KmTypeVisitor? =
+    open fun visitExpandedType(flags: Flags): KmTypeVisitor? =
         delegate?.visitExpandedType(flags)
 
     /**
@@ -423,17 +423,17 @@ abstract class KmValueParameterVisitor @JvmOverloads constructor(private val del
     /**
      * Visits the type of the value parameter, if this is **not** a `vararg` parameter.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitType(flags: Int): KmTypeVisitor? =
+    open fun visitType(flags: Flags): KmTypeVisitor? =
         delegate?.visitType(flags)
 
     /**
      * Visits the type of the value parameter, if this is a `vararg` parameter.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitVarargElementType(flags: Int): KmTypeVisitor? =
+    open fun visitVarargElementType(flags: Flags): KmTypeVisitor? =
         delegate?.visitVarargElementType(flags)
 
     /**
@@ -453,9 +453,9 @@ abstract class KmTypeParameterVisitor @JvmOverloads constructor(private val dele
     /**
      * Visits the upper bound of the type parameter.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitUpperBound(flags: Int): KmTypeVisitor? =
+    open fun visitUpperBound(flags: Flags): KmTypeVisitor? =
         delegate?.visitUpperBound(flags)
 
     /**
@@ -518,10 +518,10 @@ abstract class KmTypeVisitor @JvmOverloads constructor(private val delegate: KmT
      * Visits the type projection used in a type argument of the type based on a class or on a type alias.
      * For example, in `MutableMap<in String?, *>`, `in String?` is the type projection which is the first type argument of the type.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      * @param variance the variance of the type projection
      */
-    open fun visitArgument(flags: Int, variance: KmVariance): KmTypeVisitor? =
+    open fun visitArgument(flags: Flags, variance: KmVariance): KmTypeVisitor? =
         delegate?.visitArgument(flags, variance)
 
     /**
@@ -541,9 +541,9 @@ abstract class KmTypeVisitor @JvmOverloads constructor(private val delegate: KmT
      *
      * The type of the `foo`'s parameter in the metadata is actually `MutableList<Any>`, and its abbreviation is `A<Any>`.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitAbbreviatedType(flags: Int): KmTypeVisitor? =
+    open fun visitAbbreviatedType(flags: Flags): KmTypeVisitor? =
         delegate?.visitAbbreviatedType(flags)
 
     /**
@@ -556,20 +556,20 @@ abstract class KmTypeVisitor @JvmOverloads constructor(private val delegate: KmT
      * The type of the `foo`'s parameter in the metadata is `B<Byte>` (a type whose classifier is class `B`, and it has one type argument,
      * type `Byte?`), and its outer type is `A<*>` (a type whose classifier is class `A`, and it has one type argument, star projection).
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitOuterType(flags: Int): KmTypeVisitor? =
+    open fun visitOuterType(flags: Flags): KmTypeVisitor? =
         delegate?.visitOuterType(flags)
 
     /**
      * Visits the upper bound of the type, marking it as flexible and its contents as the lower bound. Flexible types in Kotlin include
      * platform types in Kotlin/JVM and `dynamic` type in Kotlin/JS.
      *
-     * @param flags type flags, consisting of [Flags.Type] flags
+     * @param flags type flags, consisting of [Flag.Type] flags
      * @param typeFlexibilityId id of the kind of flexibility this type has. For example, "kotlin.jvm.PlatformType" for JVM platform types,
      *                          or "kotlin.DynamicType" for JS dynamic type
      */
-    open fun visitFlexibleTypeUpperBound(flags: Int, typeFlexibilityId: String?): KmTypeVisitor? =
+    open fun visitFlexibleTypeUpperBound(flags: Flags, typeFlexibilityId: String?): KmTypeVisitor? =
         delegate?.visitFlexibleTypeUpperBound(flags, typeFlexibilityId)
 
     /**
@@ -699,18 +699,18 @@ abstract class KmEffectVisitor @JvmOverloads constructor(private val delegate: K
 abstract class KmEffectExpressionVisitor @JvmOverloads constructor(private val delegate: KmEffectExpressionVisitor? = null) {
     /**
      * Visits the basic information of the effect expression.
-     * 
-     * @param flags effect expression flags, consisting of [Flags.EffectExpression] flags
+     *
+     * @param flags effect expression flags, consisting of [Flag.EffectExpression] flags
      * @param parameterIndex optional 1-based index of the value parameter of the function, for effects which assert something about
      *                       the function parameters. The index 0 means the extension receiver parameter
      */
-    open fun visit(flags: Int, parameterIndex: Int?) {
+    open fun visit(flags: Flags, parameterIndex: Int?) {
         delegate?.visit(flags, parameterIndex)
     }
 
     /**
      * Visits the constant value used in the effect expression. May be `true`, `false` or `null`.
-     * 
+     *
      * @param value the constant value
      */
     open fun visitConstantValue(value: Any?) {
@@ -719,10 +719,10 @@ abstract class KmEffectExpressionVisitor @JvmOverloads constructor(private val d
 
     /**
      * Visits the type used as the target of an `is`-expression in the effect expression.
-     * 
-     * @param flags type flags, consisting of [Flags.Type] flags
+     *
+     * @param flags type flags, consisting of [Flag.Type] flags
      */
-    open fun visitIsInstanceType(flags: Int): KmTypeVisitor? =
+    open fun visitIsInstanceType(flags: Flags): KmTypeVisitor? =
         delegate?.visitIsInstanceType(flags)
 
     /**
diff --git a/libraries/tools/kotlinp/src/org/jetbrains/kotlin/kotlinp/printers.kt b/libraries/tools/kotlinp/src/org/jetbrains/kotlin/kotlinp/printers.kt
index b083d0121c7..a45b595c576 100644
--- a/libraries/tools/kotlinp/src/org/jetbrains/kotlin/kotlinp/printers.kt
+++ b/libraries/tools/kotlinp/src/org/jetbrains/kotlin/kotlinp/printers.kt
@@ -12,7 +12,7 @@ private object SpecialCharacters {
     const val TYPE_ALIAS_MARKER = '^'
 }
 
-private fun visitFunction(sb: StringBuilder, flags: Int, name: String): KmFunctionVisitor =
+private fun visitFunction(sb: StringBuilder, flags: Flags, name: String): KmFunctionVisitor =
     object : KmFunctionVisitor() {
         val typeParams = mutableListOf<String>()
         val params = mutableListOf<String>()
@@ -21,18 +21,18 @@ private fun visitFunction(sb: StringBuilder, flags: Int, name: String): KmFuncti
         var versionRequirement: String? = null
         var jvmDesc: String? = null
 
-        override fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+        override fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
             printType(flags) { receiverParameterType = it }
 
         override fun visitTypeParameter(
-            flags: Int, name: String, id: Int, variance: KmVariance
+            flags: Flags, name: String, id: Int, variance: KmVariance
         ): KmTypeParameterVisitor? =
             printTypeParameter(flags, name, id, variance) { typeParams.add(it) }
 
-        override fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+        override fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
             printValueParameter(flags, name) { params.add(it) }
 
-        override fun visitReturnType(flags: Int): KmTypeVisitor? =
+        override fun visitReturnType(flags: Flags): KmTypeVisitor? =
             printType(flags) { returnType = it }
 
         override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -74,7 +74,7 @@ private fun visitFunction(sb: StringBuilder, flags: Int, name: String): KmFuncti
         }
     }
 
-private fun visitProperty(sb: StringBuilder, flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor =
+private fun visitProperty(sb: StringBuilder, flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor =
     object : KmPropertyVisitor() {
         val typeParams = mutableListOf<String>()
         var receiverParameterType: String? = null
@@ -87,16 +87,16 @@ private fun visitProperty(sb: StringBuilder, flags: Int, name: String, getterFla
         var jvmSetterDesc: String? = null
         var jvmSyntheticMethodForAnnotationsDesc: String? = null
 
-        override fun visitReceiverParameterType(flags: Int): KmTypeVisitor? =
+        override fun visitReceiverParameterType(flags: Flags): KmTypeVisitor? =
             printType(flags) { receiverParameterType = it }
 
-        override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+        override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
             printTypeParameter(flags, name, id, variance) { typeParams.add(it) }
 
-        override fun visitSetterParameter(flags: Int, name: String): KmValueParameterVisitor? =
+        override fun visitSetterParameter(flags: Flags, name: String): KmValueParameterVisitor? =
             printValueParameter(flags, name) { setterParameter = it }
 
-        override fun visitReturnType(flags: Int): KmTypeVisitor? =
+        override fun visitReturnType(flags: Flags): KmTypeVisitor? =
             printType(flags) { returnType = it }
 
         override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -141,7 +141,7 @@ private fun visitProperty(sb: StringBuilder, flags: Int, name: String, getterFla
             }
             sb.append("  ")
             sb.appendFlags(flags, PROPERTY_FLAGS_MAP)
-            sb.append(if (Flags.Property.IS_VAR(flags)) "var " else "val ")
+            sb.append(if (Flag.Property.IS_VAR(flags)) "var " else "val ")
             if (typeParams.isNotEmpty()) {
                 typeParams.joinTo(sb, prefix = "<", postfix = ">")
                 sb.append(" ")
@@ -153,16 +153,16 @@ private fun visitProperty(sb: StringBuilder, flags: Int, name: String, getterFla
             if (returnType != null) {
                 sb.append(": ").append(returnType)
             }
-            if (Flags.Property.HAS_CONSTANT(flags)) {
+            if (Flag.Property.HAS_CONSTANT(flags)) {
                 sb.append(" /* = ... */")
             }
             sb.appendln()
-            if (Flags.Property.HAS_GETTER(flags)) {
+            if (Flag.Property.HAS_GETTER(flags)) {
                 sb.append("    ")
                 sb.appendFlags(getterFlags, PROPERTY_ACCESSOR_FLAGS_MAP)
                 sb.appendln("get")
             }
-            if (Flags.Property.HAS_SETTER(flags)) {
+            if (Flag.Property.HAS_SETTER(flags)) {
                 sb.append("    ")
                 sb.appendFlags(setterFlags, PROPERTY_ACCESSOR_FLAGS_MAP)
                 sb.append("set")
@@ -174,13 +174,13 @@ private fun visitProperty(sb: StringBuilder, flags: Int, name: String, getterFla
         }
     }
 
-private fun visitConstructor(sb: StringBuilder, flags: Int): KmConstructorVisitor =
+private fun visitConstructor(sb: StringBuilder, flags: Flags): KmConstructorVisitor =
     object : KmConstructorVisitor() {
         val params = mutableListOf<String>()
         var versionRequirement: String? = null
         var jvmDesc: String? = null
 
-        override fun visitValueParameter(flags: Int, name: String): KmValueParameterVisitor? =
+        override fun visitValueParameter(flags: Flags, name: String): KmValueParameterVisitor? =
             printValueParameter(flags, name) { params.add(it) }
 
         override fun visitVersionRequirement(): KmVersionRequirementVisitor? =
@@ -211,7 +211,7 @@ private fun visitConstructor(sb: StringBuilder, flags: Int): KmConstructorVisito
         }
     }
 
-private fun visitTypeAlias(sb: StringBuilder, flags: Int, name: String): KmTypeAliasVisitor =
+private fun visitTypeAlias(sb: StringBuilder, flags: Flags, name: String): KmTypeAliasVisitor =
     object : KmTypeAliasVisitor() {
         val annotations = mutableListOf<KmAnnotation>()
         val typeParams = mutableListOf<String>()
@@ -219,13 +219,13 @@ private fun visitTypeAlias(sb: StringBuilder, flags: Int, name: String): KmTypeA
         var expandedType: String? = null
         var versionRequirement: String? = null
 
-        override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+        override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
             printTypeParameter(flags, name, id, variance) { typeParams.add(it) }
 
-        override fun visitUnderlyingType(flags: Int): KmTypeVisitor? =
+        override fun visitUnderlyingType(flags: Flags): KmTypeVisitor? =
             printType(flags) { underlyingType = it }
 
-        override fun visitExpandedType(flags: Int): KmTypeVisitor? =
+        override fun visitExpandedType(flags: Flags): KmTypeVisitor? =
             printType(flags) { expandedType = it }
 
         override fun visitAnnotation(annotation: KmAnnotation) {
@@ -259,7 +259,7 @@ private fun visitTypeAlias(sb: StringBuilder, flags: Int, name: String): KmTypeA
         }
     }
 
-private fun printType(flags: Int, output: (String) -> Unit): KmTypeVisitor =
+private fun printType(flags: Flags, output: (String) -> Unit): KmTypeVisitor =
     object : KmTypeVisitor() {
         var classifier: String? = null
         val arguments = mutableListOf<String>()
@@ -281,10 +281,10 @@ private fun printType(flags: Int, output: (String) -> Unit): KmTypeVisitor =
             classifier = "$name${SpecialCharacters.TYPE_ALIAS_MARKER}"
         }
 
-        override fun visitAbbreviatedType(flags: Int): KmTypeVisitor? =
+        override fun visitAbbreviatedType(flags: Flags): KmTypeVisitor? =
             printType(flags) { abbreviatedType = it }
 
-        override fun visitArgument(flags: Int, variance: KmVariance): KmTypeVisitor? =
+        override fun visitArgument(flags: Flags, variance: KmVariance): KmTypeVisitor? =
             printType(flags) { argumentTypeString ->
                 arguments += buildString {
                     if (variance != KmVariance.INVARIANT) {
@@ -298,10 +298,10 @@ private fun printType(flags: Int, output: (String) -> Unit): KmTypeVisitor =
             arguments += "*"
         }
 
-        override fun visitOuterType(flags: Int): KmTypeVisitor? =
+        override fun visitOuterType(flags: Flags): KmTypeVisitor? =
             printType(flags) { outerType = it }
 
-        override fun visitFlexibleTypeUpperBound(flags: Int, typeFlexibilityId: String?): KmTypeVisitor? =
+        override fun visitFlexibleTypeUpperBound(flags: Flags, typeFlexibilityId: String?): KmTypeVisitor? =
             if (typeFlexibilityId == JvmTypeExtensionVisitor.PLATFORM_TYPE_ID) {
                 printType(flags) { platformTypeUpperBound = it }
             } else null
@@ -336,7 +336,7 @@ private fun printType(flags: Int, output: (String) -> Unit): KmTypeVisitor =
                 if (arguments.isNotEmpty()) {
                     arguments.joinTo(this, prefix = "<", postfix = ">")
                 }
-                if (Flags.Type.IS_NULLABLE(flags)) {
+                if (Flag.Type.IS_NULLABLE(flags)) {
                     append("?")
                 }
                 if (abbreviatedType != null) {
@@ -352,12 +352,14 @@ private fun printType(flags: Int, output: (String) -> Unit): KmTypeVisitor =
         }
     }
 
-private fun printTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance, output: (String) -> Unit): KmTypeParameterVisitor =
+private fun printTypeParameter(
+    flags: Flags, name: String, id: Int, variance: KmVariance, output: (String) -> Unit
+): KmTypeParameterVisitor =
     object : KmTypeParameterVisitor() {
         val bounds = mutableListOf<String>()
         val jvmAnnotations = mutableListOf<KmAnnotation>()
 
-        override fun visitUpperBound(flags: Int): KmTypeVisitor? =
+        override fun visitUpperBound(flags: Flags): KmTypeVisitor? =
             printType(flags) { bounds += it }
 
         override fun visitExtensions(type: KmExtensionType): KmTypeParameterExtensionVisitor? {
@@ -386,15 +388,15 @@ private fun printTypeParameter(flags: Int, name: String, id: Int, variance: KmVa
         }
     }
 
-private fun printValueParameter(flags: Int, name: String, output: (String) -> Unit): KmValueParameterVisitor =
+private fun printValueParameter(flags: Flags, name: String, output: (String) -> Unit): KmValueParameterVisitor =
     object : KmValueParameterVisitor() {
         var varargElementType: String? = null
         var type: String? = null
 
-        override fun visitType(flags: Int): KmTypeVisitor? =
+        override fun visitType(flags: Flags): KmTypeVisitor? =
             printType(flags) { type = it }
 
-        override fun visitVarargElementType(flags: Int): KmTypeVisitor? =
+        override fun visitVarargElementType(flags: Flags): KmTypeVisitor? =
             printType(flags) { varargElementType = it }
 
         override fun visitEnd() {
@@ -405,7 +407,7 @@ private fun printValueParameter(flags: Int, name: String, output: (String) -> Un
                 } else {
                     append(name).append(": ").append(type)
                 }
-                if (Flags.ValueParameter.DECLARES_DEFAULT_VALUE(flags)) {
+                if (Flag.ValueParameter.DECLARES_DEFAULT_VALUE(flags)) {
                     append(" /* = ... */")
                 }
             })
@@ -491,7 +493,7 @@ private fun printVersionRequirement(output: (String) -> Unit): KmVersionRequirem
         }
     }
 
-private fun StringBuilder.appendFlags(flags: Int, map: Map<MetadataFlag, String>) {
+private fun StringBuilder.appendFlags(flags: Flags, map: Map<Flag, String>) {
     for ((modifier, string) in map) {
         if (modifier(flags)) {
             append(string)
@@ -508,13 +510,13 @@ class ClassPrinter : KmClassVisitor(), AbstractPrinter<KotlinClassMetadata.Class
     private val sb = StringBuilder()
     private val result = StringBuilder()
 
-    private var flags: Int? = null
+    private var flags: Flags? = null
     private var name: ClassName? = null
     private val typeParams = mutableListOf<String>()
     private val supertypes = mutableListOf<String>()
     private var versionRequirement: String? = null
 
-    override fun visit(flags: Int, name: ClassName) {
+    override fun visit(flags: Flags, name: ClassName) {
         this.flags = flags
         this.name = name
     }
@@ -537,22 +539,22 @@ class ClassPrinter : KmClassVisitor(), AbstractPrinter<KotlinClassMetadata.Class
         result.appendln("}")
     }
 
-    override fun visitTypeParameter(flags: Int, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
+    override fun visitTypeParameter(flags: Flags, name: String, id: Int, variance: KmVariance): KmTypeParameterVisitor? =
         printTypeParameter(flags, name, id, variance) { typeParams.add(it) }
 
-    override fun visitSupertype(flags: Int): KmTypeVisitor? =
+    override fun visitSupertype(flags: Flags): KmTypeVisitor? =
         printType(flags) { supertypes.add(it) }
 
-    override fun visitConstructor(flags: Int): KmConstructorVisitor? =
+    override fun visitConstructor(flags: Flags): KmConstructorVisitor? =
         visitConstructor(sb, flags)
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         visitFunction(sb, flags, name)
 
-    override fun visitProperty(flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor? =
+    override fun visitProperty(flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor? =
         visitProperty(sb, flags, name, getterFlags, setterFlags)
 
-    override fun visitTypeAlias(flags: Int, name: String): KmTypeAliasVisitor? =
+    override fun visitTypeAlias(flags: Flags, name: String): KmTypeAliasVisitor? =
         visitTypeAlias(sb, flags, name)
 
     override fun visitCompanionObject(name: String) {
@@ -593,13 +595,13 @@ abstract class PackagePrinter : KmPackageVisitor() {
         sb.appendln("}")
     }
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         visitFunction(sb, flags, name)
 
-    override fun visitProperty(flags: Int, name: String, getterFlags: Int, setterFlags: Int): KmPropertyVisitor? =
+    override fun visitProperty(flags: Flags, name: String, getterFlags: Flags, setterFlags: Flags): KmPropertyVisitor? =
         visitProperty(sb, flags, name, getterFlags, setterFlags)
 
-    override fun visitTypeAlias(flags: Int, name: String): KmTypeAliasVisitor? =
+    override fun visitTypeAlias(flags: Flags, name: String): KmTypeAliasVisitor? =
         visitTypeAlias(sb, flags, name)
 }
 
@@ -615,7 +617,7 @@ class LambdaPrinter : KmLambdaVisitor(), AbstractPrinter<KotlinClassMetadata.Syn
         appendln("lambda {")
     }
 
-    override fun visitFunction(flags: Int, name: String): KmFunctionVisitor? =
+    override fun visitFunction(flags: Flags, name: String): KmFunctionVisitor? =
         visitFunction(sb, flags, name)
 
     override fun visitEnd() {
@@ -679,84 +681,84 @@ class ModuleFilePrinter : KmModuleVisitor() {
 }
 
 private val VISIBILITY_FLAGS_MAP = mapOf(
-    Flags.IS_INTERNAL to "internal",
-    Flags.IS_PRIVATE to "private",
-    Flags.IS_PRIVATE_TO_THIS to "private",
-    Flags.IS_PROTECTED to "protected",
-    Flags.IS_PUBLIC to "public",
-    Flags.IS_LOCAL to "local"
+    Flag.IS_INTERNAL to "internal",
+    Flag.IS_PRIVATE to "private",
+    Flag.IS_PRIVATE_TO_THIS to "private",
+    Flag.IS_PROTECTED to "protected",
+    Flag.IS_PUBLIC to "public",
+    Flag.IS_LOCAL to "local"
 )
 
 private val COMMON_FLAGS_MAP = VISIBILITY_FLAGS_MAP + mapOf(
-    Flags.IS_FINAL to "final",
-    Flags.IS_OPEN to "open",
-    Flags.IS_ABSTRACT to "abstract",
-    Flags.IS_SEALED to "sealed"
+    Flag.IS_FINAL to "final",
+    Flag.IS_OPEN to "open",
+    Flag.IS_ABSTRACT to "abstract",
+    Flag.IS_SEALED to "sealed"
 )
 
 private val CLASS_FLAGS_MAP = COMMON_FLAGS_MAP + mapOf(
-    Flags.Class.IS_INNER to "inner",
-    Flags.Class.IS_DATA to "data",
-    Flags.Class.IS_EXTERNAL to "external",
-    Flags.Class.IS_EXPECT to "expect",
-    Flags.Class.IS_INLINE to "inline",
+    Flag.Class.IS_INNER to "inner",
+    Flag.Class.IS_DATA to "data",
+    Flag.Class.IS_EXTERNAL to "external",
+    Flag.Class.IS_EXPECT to "expect",
+    Flag.Class.IS_INLINE to "inline",
 
-    Flags.Class.IS_CLASS to "class",
-    Flags.Class.IS_INTERFACE to "interface",
-    Flags.Class.IS_ENUM_CLASS to "enum class",
-    Flags.Class.IS_ENUM_ENTRY to "enum entry",
-    Flags.Class.IS_ANNOTATION_CLASS to "annotation class",
-    Flags.Class.IS_OBJECT to "object",
-    Flags.Class.IS_COMPANION_OBJECT to "companion object"
+    Flag.Class.IS_CLASS to "class",
+    Flag.Class.IS_INTERFACE to "interface",
+    Flag.Class.IS_ENUM_CLASS to "enum class",
+    Flag.Class.IS_ENUM_ENTRY to "enum entry",
+    Flag.Class.IS_ANNOTATION_CLASS to "annotation class",
+    Flag.Class.IS_OBJECT to "object",
+    Flag.Class.IS_COMPANION_OBJECT to "companion object"
 )
 
 private val CONSTRUCTOR_FLAGS_MAP = VISIBILITY_FLAGS_MAP + mapOf(
-    Flags.Constructor.IS_PRIMARY to "/* primary */"
+    Flag.Constructor.IS_PRIMARY to "/* primary */"
 )
 
 private val FUNCTION_FLAGS_MAP = COMMON_FLAGS_MAP + mapOf(
-    Flags.Function.IS_DECLARATION to "",
-    Flags.Function.IS_FAKE_OVERRIDE to "/* fake override */",
-    Flags.Function.IS_DELEGATION to "/* delegation */",
-    Flags.Function.IS_SYNTHESIZED to "/* synthesized */",
+    Flag.Function.IS_DECLARATION to "",
+    Flag.Function.IS_FAKE_OVERRIDE to "/* fake override */",
+    Flag.Function.IS_DELEGATION to "/* delegation */",
+    Flag.Function.IS_SYNTHESIZED to "/* synthesized */",
 
-    Flags.Function.IS_OPERATOR to "operator",
-    Flags.Function.IS_INFIX to "infix",
-    Flags.Function.IS_INLINE to "inline",
-    Flags.Function.IS_TAILREC to "tailrec",
-    Flags.Function.IS_EXTERNAL to "external",
-    Flags.Function.IS_SUSPEND to "suspend",
-    Flags.Function.IS_EXPECT to "expect"
+    Flag.Function.IS_OPERATOR to "operator",
+    Flag.Function.IS_INFIX to "infix",
+    Flag.Function.IS_INLINE to "inline",
+    Flag.Function.IS_TAILREC to "tailrec",
+    Flag.Function.IS_EXTERNAL to "external",
+    Flag.Function.IS_SUSPEND to "suspend",
+    Flag.Function.IS_EXPECT to "expect"
 )
 
 private val PROPERTY_FLAGS_MAP = COMMON_FLAGS_MAP + mapOf(
-    Flags.Property.IS_DECLARATION to "",
-    Flags.Property.IS_FAKE_OVERRIDE to "/* fake override */",
-    Flags.Property.IS_DELEGATION to "/* delegation */",
-    Flags.Property.IS_SYNTHESIZED to "/* synthesized */",
+    Flag.Property.IS_DECLARATION to "",
+    Flag.Property.IS_FAKE_OVERRIDE to "/* fake override */",
+    Flag.Property.IS_DELEGATION to "/* delegation */",
+    Flag.Property.IS_SYNTHESIZED to "/* synthesized */",
 
-    Flags.Property.IS_CONST to "const",
-    Flags.Property.IS_LATEINIT to "lateinit",
-    Flags.Property.IS_EXTERNAL to "external",
-    Flags.Property.IS_DELEGATED to "/* delegated */",
-    Flags.Property.IS_EXPECT to "expect"
+    Flag.Property.IS_CONST to "const",
+    Flag.Property.IS_LATEINIT to "lateinit",
+    Flag.Property.IS_EXTERNAL to "external",
+    Flag.Property.IS_DELEGATED to "/* delegated */",
+    Flag.Property.IS_EXPECT to "expect"
 )
 
 private val PROPERTY_ACCESSOR_FLAGS_MAP = COMMON_FLAGS_MAP + mapOf(
-    Flags.PropertyAccessor.IS_NOT_DEFAULT to "/* non-default */",
-    Flags.PropertyAccessor.IS_EXTERNAL to "external",
-    Flags.PropertyAccessor.IS_INLINE to "inline"
+    Flag.PropertyAccessor.IS_NOT_DEFAULT to "/* non-default */",
+    Flag.PropertyAccessor.IS_EXTERNAL to "external",
+    Flag.PropertyAccessor.IS_INLINE to "inline"
 )
 
 private val VALUE_PARAMETER_FLAGS_MAP = mapOf(
-    Flags.ValueParameter.IS_CROSSINLINE to "crossinline",
-    Flags.ValueParameter.IS_NOINLINE to "noinline"
+    Flag.ValueParameter.IS_CROSSINLINE to "crossinline",
+    Flag.ValueParameter.IS_NOINLINE to "noinline"
 )
 
 private val TYPE_PARAMETER_FLAGS_MAP = mapOf(
-    Flags.TypeParameter.IS_REIFIED to "reified"
+    Flag.TypeParameter.IS_REIFIED to "reified"
 )
 
 private val TYPE_FLAGS_MAP = mapOf(
-    Flags.Type.IS_SUSPEND to "suspend"
+    Flag.Type.IS_SUSPEND to "suspend"
 )