AltiVec Instruction Set

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:
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