JVM IR: do not use descriptors in IrTypeMapper.writeFormalTypeParameters

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/IrTypeMapper.kt

@@ -42,8 +42,16 @@ class IrTypeMapper(private val context: JvmBackendContext) {
         context.getLocalClassInfo(irClass)?.internalName
             ?: JvmCodegenUtil.sanitizeNameIfNeeded(computeInternalName(irClass), context.state.languageVersionSettings)
 
-    fun writeFormalTypeParameters(irParameters: List<IrTypeParameter>, sw: JvmSignatureWriter) =
-        kotlinTypeMapper.writeFormalTypeParameters(irParameters.map { it.descriptor }, sw)
+    fun writeFormalTypeParameters(irParameters: List<IrTypeParameter>, sw: JvmSignatureWriter) {
+        if (sw.skipGenericSignature()) return
+        with(KotlinTypeMapper) {
+            for (typeParameter in irParameters) {
+                typeSystem.writeFormalTypeParameter(typeParameter.symbol, sw) { type, mode ->
+                    mapType(type as IrType, mode, sw)
+                }
+            }
+        }
+    }
 
     fun boxType(irType: IrType): Type =
         AsmUtil.boxType(mapType(irType), irType.toKotlinType(), kotlinTypeMapper)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/IrTypeSystemContext.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.ir.types.impl.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.FqNameUnsafe
+import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
 import org.jetbrains.kotlin.types.TypeSystemCommonBackendContext
 import org.jetbrains.kotlin.types.Variance
@@ -325,6 +326,14 @@ interface IrTypeSystemContext : TypeSystemContext, TypeSystemCommonSuperTypesCon
 
     override fun TypeConstructorMarker.getClassFqNameUnsafe(): FqNameUnsafe? =
         (this as IrClassSymbol).owner.fqNameWhenAvailable?.toUnsafe()
+
+    override fun TypeParameterMarker.getName(): Name =
+        (this as IrTypeParameterSymbol).owner.name
+
+    override fun KotlinTypeMarker.isInterfaceOrAnnotationClass(): Boolean {
+        val irClass = (this as IrType).classOrNull?.owner
+        return irClass != null && (irClass.isInterface || irClass.isAnnotationClass)
+    }
 }
 
 fun extractTypeParameters(klass: IrDeclarationParent): List<IrTypeParameter> {