Keith E. Diefendorff

AltiVec extension to PowerPC accelerates media processing

There is a clear trend in personal computing toward multimedia-rich applications. These applications will incorporate a wide variety of multimedia technologies, including audio and video compression, 2D image processing, 3D graphics, speech and handwriting recognition, media mining, and narrow/broadband signal processing for communication. In response to this demand, major microprocessor vendors have announced architectural extensions to their general-purpose processors in an effort to improve their multimedia performance. Intel extended IA-32 with MMX and SSE (alias KNI), Sun enhanced Sparc with VIS, Hewlett-Packard added MAX to its PA-RISC architecture, Silicon Graphics extended the MIPS architecture with MDMX, and Digital (now Compaq) added MVI to Alpha. This article describes the most recent, and what we believe to be the most comprehensive, addition to this list: PowerPCs AltiVec, AltiVec speeds not only media processing but also nearly any application in which data parallelism exists, as demonstrated by a cycle-accurate simulation of Motorolas MPC 7400, the heart of Apple G4 systems.

How multimedia workloads will change processor design

Workloads drive architecture design and will change in the next two decades. For high-performance, general-purpose processors, there is a consensus that multimedia will continue to grow in importance. The authors predict these processors will incorporate more media processing capabilities, eventually bringing about the demise of specialized media processors, except perhaps, in embedded applications. These enhanced general-purpose processor capabilities will arise from multimedia applications that require real-time response, continuous-media data types and significant fine-grained data parallelism.

Hot Chips 16: Power, Parallelism, and Memory Performance

We are pleased to introduce this special issue of IEEE Micro featuring papers that capture the best presentations from the Hot Chips 16 conference held last summer at Stanford University.