AltiVec — An Overview
AltiVec is a SIMD instruction set developed by Apple around 1998. It is a floating-point instruction set used in PowerPC microprocessors. It operates on 32-bit floating point numbers, as well as 8, 16, and 32-bit integers. It provides 32 registers which are 128 bits wide. AltiVec is related to VMX, which was developed by IBM.A good overview of the AltiVec instruction set can be found here:
http://developer.apple.com/hardwaredrivers/ve/instruction_crossref.html.