OS X and iOS Kernel Programming

SSE and Floating Point in the Kernel

Streaming SIMD Extensions (SSE) is the successor to MMX and is a special instruction set found on most modern Intel and AMD processors that allow common instructions such as add, multiply, and shift to be performed on arrays (vectors) of values instead of single values (scalar). This can greatly speed up many computation tasks, especially in areas such as digital signal processing, audio, graphics, and video. Normally the kernel is not a great place to perform heavy computation, but there are some areas where it is unavoidable—for example, in the case of audio drivers, which need to convert audio samples from multiple user space applications and mix them into a single buffer for output. Software implementations ...