Code optimization when using multiple reader locks and a non-reader lock

Abstract

A way to use multiple-reader locks for those paths where no writes occur is provided. Only if one of the writing paths executes will a full writer lock be acquired. Two copies of the critical section comprising a reading version and a writing version are created. The default execution leads to the reader version, which only acquires a reader-lock. The reader version of the code executes prior to execution of the writer lock only version, otherwise bypassing the writer lock only version. If the execution leads to a path in which a write would occur, the reader only version branches to the beginning of the writer version. The writer version is identical to the original code and obtains a full writer lock. If execution in the reader lock does not lead to a path that writes, then only the reader lock is acquired.