Cooperative thread array reduction and scan operations

摘要

One embodiment of the present invention sets forth a technique for performing aggregation operations across multiple threads that execute independently. Aggregation is specified as part of a barrier synchronization or barrier arrival instruction, where in addition to performing the barrier synchronization or arrival, the instruction aggregates (using reduction or scan operations) values supplied by each thread. When a thread executes the barrier aggregation instruction the thread contributes to a scan or reduction result, and waits to execute any more instructions until after all of the threads have executed the barrier aggregation instruction. A reduction result is communicated to each thread after all of the threads have executed the barrier aggregation instruction and a scan result is communicated to each thread as the barrier aggregation instruction is executed by the thread.

主权项

1. A method for performing a scan operation across multiple threads, the method comprising:
receiving a barrier instruction that specifies the scan operation for execution by a first thread of the multiple threads; combining a value associated with the first thread with an scan result for the multiple threads; communicating the scan result to the first thread; and causing another instruction to be executed without waiting until the barrier instruction is received by a second thread of the multiple threads.