GPGPU Programming for Games and Science

Chapter 3

SIMD Computing

3.1 Intel Streaming SIMD Extensions

Current CPUs have small-scale parallel support for 3D mathematics com-

putations using single-instruction-multiple-data (SIMD) computing. The pro-

cessors provide 128-bit registers, each register storing four 32-bit

float values.

The fundamental concepts are

• to provide addition and multiplication of four numbers simultaneously

(a single instruction applied to multiple data) and

• to allow shuffling, sometimes called swizzling, of the four components.

Of course, such hardware has support for more than just these operations.

In this section I will briefly summarize the SIMD support for Intel CPUs, ...