[KLIB] Fix annotation type deserialization

Instead of hardcoded `Unit` restore it basing on annotation class and
constructor's type arguments

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/impl/IrSimpleTypeImpl.kt

@@ -12,27 +12,19 @@ import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.Variance
 
-class IrSimpleTypeImpl(
-    kotlinType: KotlinType?,
-    override val classifier: IrClassifierSymbol,
-    override val hasQuestionMark: Boolean,
-    override val arguments: List<IrTypeArgument>,
-    override val annotations: List<IrConstructorCall>,
-    override val abbreviation: IrTypeAbbreviation? = null
-) : IrTypeBase(kotlinType), IrSimpleType {
+abstract class IrAbstractSimpleType(kotlinType: KotlinType?) : IrTypeBase(kotlinType), IrSimpleType {
+
     override val variance: Variance
         get() = Variance.INVARIANT
 
-    constructor(
-        classifier: IrClassifierSymbol,
-        hasQuestionMark: Boolean,
-        arguments: List<IrTypeArgument>,
-        annotations: List<IrConstructorCall>,
-        abbreviation: IrTypeAbbreviation? = null
-    ) : this(null, classifier, hasQuestionMark, arguments, annotations, abbreviation)
+    abstract override val classifier: IrClassifierSymbol
+    abstract override val hasQuestionMark: Boolean
+    abstract override val arguments: List<IrTypeArgument>
+    abstract override val annotations: List<IrConstructorCall>
+    abstract override val abbreviation: IrTypeAbbreviation?
 
     override fun equals(other: Any?): Boolean =
-        other is IrSimpleTypeImpl &&
+        other is IrAbstractSimpleType &&
                 FqNameEqualityChecker.areEqual(classifier, other.classifier) &&
                 hasQuestionMark == other.hasQuestionMark &&
                 arguments == other.arguments
@@ -43,6 +35,41 @@ class IrSimpleTypeImpl(
                 arguments.hashCode()
 }
 
+abstract class IrDelegatedSimpleType : IrAbstractSimpleType(null) {
+
+    protected abstract val delegate: IrSimpleType
+
+    override val classifier: IrClassifierSymbol
+        get() = delegate.classifier
+    override val hasQuestionMark: Boolean
+        get() = delegate.hasQuestionMark
+    override val arguments: List<IrTypeArgument>
+        get() = delegate.arguments
+    override val abbreviation: IrTypeAbbreviation?
+        get() = delegate.abbreviation
+    override val annotations: List<IrConstructorCall>
+        get() = delegate.annotations
+}
+
+
+class IrSimpleTypeImpl(
+    kotlinType: KotlinType?,
+    override val classifier: IrClassifierSymbol,
+    override val hasQuestionMark: Boolean,
+    override val arguments: List<IrTypeArgument>,
+    override val annotations: List<IrConstructorCall>,
+    override val abbreviation: IrTypeAbbreviation? = null
+) : IrAbstractSimpleType(kotlinType) {
+
+    constructor(
+        classifier: IrClassifierSymbol,
+        hasQuestionMark: Boolean,
+        arguments: List<IrTypeArgument>,
+        annotations: List<IrConstructorCall>,
+        abbreviation: IrTypeAbbreviation? = null
+    ) : this(null, classifier, hasQuestionMark, arguments, annotations, abbreviation)
+}
+
 class IrSimpleTypeBuilder {
     var kotlinType: KotlinType? = null
     var classifier: IrClassifierSymbol? = null

compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrBodyDeserializer.kt

@@ -18,6 +18,8 @@ import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.types.impl.*
+import org.jetbrains.kotlin.ir.util.parentAsClass
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrBlock as ProtoBlock
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrBlockBody as ProtoBlockBody
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrBranch as ProtoBranch
@@ -34,10 +36,10 @@ import org.jetbrains.kotlin.backend.common.serialization.proto.IrDoWhile as Prot
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrDynamicMemberExpression as ProtoDynamicMemberExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrDynamicOperatorExpression as ProtoDynamicOperatorExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrEnumConstructorCall as ProtoEnumConstructorCall
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrErrorCallExpression as ProtoErrorCallExpression
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrErrorExpression as ProtoErrorExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrExpression as ProtoExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrFunctionExpression as ProtoFunctionExpression
-import org.jetbrains.kotlin.backend.common.serialization.proto.IrErrorExpression as ProtoErrorExpression
-import org.jetbrains.kotlin.backend.common.serialization.proto.IrErrorCallExpression as ProtoErrorCallExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrFunctionReference as ProtoFunctionReference
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrGetClass as ProtoGetClass
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrGetEnumValue as ProtoGetEnumValue
@@ -188,7 +190,53 @@ class IrBodyDeserializer(
     }
 
     fun deserializeAnnotation(proto: ProtoConstructorCall): IrConstructorCall {
-        return deserializeConstructorCall(proto, 0, 0, builtIns.unitType) // TODO: need a proper deserialization here
+
+        // TODO: probably a bit more abstraction possible here up to `IrMemberAccessExpression`
+        // but at this point further complexization looks overengineered
+        class IrAnnotationType : IrDelegatedSimpleType() {
+
+            var irConstructorCall: IrConstructorCall? = null
+
+            override val delegate: IrSimpleType by lazy { resolveType() }
+
+            private fun resolveType(): IrSimpleType {
+                val constructorCall = irConstructorCall ?: error("irConstructorCall should not be null at this stage")
+                irConstructorCall = null
+
+                val klass = constructorCall.symbol.owner.parentAsClass
+
+                val typeParameters = extractTypeParameters(klass)
+
+                val typeArguments = ArrayList<IrTypeArgument>(typeParameters.size)
+                val typeParameterSymbols = ArrayList<IrTypeParameterSymbol>(typeParameters.size)
+                val rawType = with(IrSimpleTypeBuilder()) {
+                    arguments = typeParameters.run {
+                        mapTo(ArrayList(size)) {
+                            classifier = it.symbol
+                            buildTypeProjection()
+                        }
+                    }
+                    classifier = klass.symbol
+                    buildSimpleType()
+                }
+
+
+                for (i in typeParameters.indices) {
+                    val typeParameter = typeParameters[i]
+                    val callTypeArgument = constructorCall.getTypeArgument(i) ?: error("No type argument for id $i")
+                    val typeArgument = makeTypeProjection(callTypeArgument, typeParameter.variance)
+                    typeArguments.add(typeArgument)
+                    typeParameterSymbols.add(typeParameter.symbol)
+                }
+
+                val substitutor = IrTypeSubstitutor(typeParameterSymbols, typeArguments, builtIns)
+                return substitutor.substitute(rawType) as IrSimpleType
+            }
+        }
+
+        val irType = IrAnnotationType()
+        // TODO: use real coordinates
+        return deserializeConstructorCall(proto, 0, 0, irType).also { irType.irConstructorCall = it }
     }
 
     fun deserializeConstructorCall(proto: ProtoConstructorCall, start: Int, end: Int, type: IrType): IrConstructorCall {