Vectorization

Vectorization is the software optimization of using single instruction multiple data (SIMD) instructions to perform computation in parallel. Since the instructions act on multiple items of data at the same time, this is really an example of parallelism at the level of the instruction and data. As such, it can result in a significant gain in performance without the overhead associated with synchronizing and managing multiple threads.

Listing 10.26 shows that the simplest example of this is the loop. This loop adds two vectors and places the result into a third.