Any other 33-year-old who noticed a sudden growth spurt would run to a doctor, but it seems that Intel’s x86 architecture will never stop growing. New extensions appeared this year in Sandy Bridge processors, more are coming in next year’s Ivy Bridge, and still more will come in 2013 with a processor code-named Haswell. Is the x86 growing stronger or fatter?
Stronger! True, the extensions add more complexity to what is already the world’s most complex microprocessor architecture—and one of the oldest active architectures, having been born in 1978. But the extensions are mostly brain cells, not cellulite.
This year, Intel’s Sandy Bridge and AMD’s Bulldozer processors introduced the Advanced Vector Extensions (AVX). Besides adding many new programming instructions, AVX doubles the width of the 128-bit registers that Intel introduced in 1999 with the Streaming SIMD Extensions (SSE). Most AVX instructions perform vector floating-point arithmetic and are useful in a variety of applications, from games and graphics to scientific and engineering computing.
Next year’s Ivy Bridge will add a few more instructions to the Sandy Bridge design and will be the first chip manufactured with Intel’s 22nm tri-gate transistor technology. The most interesting instruction accesses a new on-chip true random-number generator. True random numbers are vital for security and are superior to software-generated pseudo-random numbers.
The big growth spurt comes in 2013 with Haswell, a next-generation CPU design. Haswell will introduce AVX2 and FMA3, which add hundreds of new or improved instructions for vector integer arithmetic and floating-point operations. As with AVX, the applications are varied, but media processing should get a boost.
After studying Intel’s 595-page AVX/AVX2/FMA3 programming manual, I think these extensions will bulk up the x86 with lean muscle, not flabby fat. Besides, who would want to power a 2013 computer with a 1978 processor?
Tom Halfhill was formerly a senior editor for Byte magazine and is now an analyst for Microprocessor Report.