Runtime: export function to import own functionality to target module (perhaps it's frontend task)

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/native/llvm/Runtime.kt

@@ -34,6 +34,15 @@ class Runtime(private val bitcodeFile: String) {
     val fieldTableRecordType = LLVMGetTypeByName(llvmModule, "struct.FieldTableRecord")
     val methodTableRecordType = LLVMGetTypeByName(llvmModule, "struct.MethodTableRecord")
     val globalhHashType = LLVMGetTypeByName(llvmModule, "struct.GlobalHash")
+    val allocInstanceFunction = LLVMGetNamedFunction(llvmModule, "AllocInstance")
+
+    fun importRuntime(module: LLVMOpaqueModule) {
+        memScoped {
+            val params = allocNativeArrayOf(LLVMOpaqueType, pointerType(typeInfoType), LLVMInt32Type())
+            val functionAllocInstanceType = LLVMFunctionType(pointerType(LLVMInt8Type()),params[0], 2, 0)
+            LLVMAddFunction(module, "AllocInstance", functionAllocInstanceType)
+        }
+    }
 
     val target = LLVMGetTarget(llvmModule)!!.asCString().toString()