Introduce inline-only functions

They have private visibility in bytecode

compiler/backend/src/org/jetbrains/kotlin/codegen/AsmUtil.java

@@ -323,6 +323,8 @@ public class AsmUtil {
         DeclarationDescriptor containingDeclaration = memberDescriptor.getContainingDeclaration();
         Visibility memberVisibility = memberDescriptor.getVisibility();
 
+        if (AnnotationUtilKt.isInlineOnly(memberDescriptor)) return ACC_PRIVATE;
+
         if (memberVisibility == Visibilities.LOCAL && memberDescriptor instanceof CallableMemberDescriptor) {
             return ACC_PUBLIC;
         }

compiler/backend/src/org/jetbrains/kotlin/codegen/context/CodegenContext.java

@@ -29,6 +29,7 @@ import org.jetbrains.kotlin.load.java.JavaVisibilities;
 import org.jetbrains.kotlin.load.java.descriptors.SamConstructorDescriptor;
 import org.jetbrains.kotlin.psi.KtFile;
 import org.jetbrains.kotlin.resolve.DescriptorUtils;
+import org.jetbrains.kotlin.resolve.annotations.AnnotationUtilKt;
 import org.jetbrains.kotlin.storage.LockBasedStorageManager;
 import org.jetbrains.kotlin.storage.NullableLazyValue;
 import org.jetbrains.kotlin.types.KotlinType;
@@ -609,6 +610,8 @@ public abstract class CodegenContext<T extends DeclarationDescriptor> {
             boolean withinInline,
             boolean isSuperCall
     ) {
+        if (AnnotationUtilKt.isInlineOnly(unwrappedDescriptor)) return false;
+
         return isSuperCall && withinInline ||
                (accessFlag & ACC_PRIVATE) != 0 ||
                ((accessFlag & ACC_PROTECTED) != 0 &&