Abstract: A method may include creating objects by executing a program in a first thread. Creating the objects may include allocating, for each object, storage based on a shape assigned to the object. The storage may include separate, non-reusable storage locations. Each storage location may correspond to a field of the object. The shape may include a sharing status and a mapping of each field of the object to a storage location. The method may further include detecting that the program is initiating a second concurrent thread of execution, and designating a subset of objects as shared objects. Designating the subset of objects as shared objects may include setting the sharing status of the shape assigned to each shared object to indicate that the object is shared. The method may further include initiating tracking of shared objects and implementing a write barrier when writing to shared objects.

Abstract: A method may include creating objects by executing a program in a first thread. Creating the objects may include allocating, for each object, storage based on a shape assigned to the object. The storage may include separate, non-reusable storage locations. Each storage location may correspond to a field of the object. The shape may include a sharing status and a mapping of each field of the object to a storage location. The method may further include detecting that the program is initiating a second concurrent thread of execution, and designating a subset of objects as shared objects. Designating the subset of objects as shared objects may include setting the sharing status of the shape assigned to each shared object to indicate that the object is shared. The method may further include initiating tracking of shared objects and implementing a write barrier when writing to shared objects.