Implementing Concurrency Safety Via Deferred Synchronization of Divergent Mutations

One or more non-transitory computer-readable media storing program instructions that, when executed by one or more hardware processors, cause performance of operations comprising:

• performing a first part of a synchronization process for two or more copies of a set of runtime objects, the set of runtime objects comprising a first object and a second object, wherein performing the first part of the synchronization process comprises:
• generating a copy of the first object, the copy of the first object comprising a first pointer to a first copy of the second object;
• subsequent to performing the first part of the synchronization process and responsive to a program instance requesting performance of a program task targeting the second object, performing a second part of the synchronization process, wherein performing the second part of the synchronization process comprises:
• decoding a first set of one or more bits in the first pointer that are not allocated for addressing a memory location, the first set of one or more bits comprising a first value indicating that the first pointer has not been updated during the synchronization process;
• based at least in part on the first set of one or more bits comprising the first value, determining that the first copy of the second object was not created during the synchronization process;
• responsive to determining that the first copy of the second object was not created during the synchronization process, generating a second copy of the second object;
• and
• subsequent to performing the second part of the synchronization process, performing the program task targeting the second object, wherein performing the program task targeting the second object comprises accessing the second copy of the second object.

A system comprising:

• one or more hardware processors;
• one or more non-transitory computer-readable media;
• and
• program instructions stored on the one or more non-transitory computer-readable media that, when executed by the one or more hardware processors, cause the system to perform operations comprising:
• performing a first part of a synchronization process for two or more copies of a set of runtime objects, the set of runtime objects comprising a first object and a second object, wherein performing the first part of the synchronization process comprises:
• generating a copy of the first object, the copy of the first object comprising a first pointer to a first copy of the second object;
• subsequent to performing the first part of the synchronization process and responsive to a program instance requesting performance of a program task targeting the second object, performing a second part of the synchronization process, wherein performing the second part of the synchronization process comprises:
• decoding a first set of one or more bits in the first pointer that are not allocated for addressing a memory location, the first set of one or more bits comprising a first value indicating that the first pointer has not been updated during the synchronization process;
• based at least in part on the first set of one or more bits comprising the first value, determining that the first copy of the second object was not created during the synchronization process;
• responsive to determining that the first copy of the second object was not created during the synchronization process, generating a second copy of the second object;
• and
• subsequent to performing the second part of the synchronization process, performing the program task targeting the second object, wherein performing the program task targeting the second object comprises accessing the second copy of the second object.