Streaming SIMD Extensions 5

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SSE5 ( Streaming SIMD Extensions 5 ) was a planned instruction set extension from AMD for x86 processors. It comprised 47 commands that should be particularly suitable for accelerating certain algorithms, for example FFT , DCT or encryption with AES . Among other things, SSE5 contained so-called three-operand instructions, which store the calculation result not in one of the two original registers but in a third one, which potentially leads to fewer machine instructions in the program code and thus to a higher execution speed. The commands themselves were based on operands with a width of 128 bits and could thus work with up to four 32-bit values ​​at the same time. AMD planned to build an SSE5 processing unit into the Bulldozer core.

However, even before the bulldozer architecture was introduced, AMD rescheduled. First, AMD announced that it would postpone Bulldozer to at least 2011, which after the original schedule of 2009 and the previous postponement to 2010 meant another year of delay. On May 6, 2009, AMD announced in its tech blog that SSE5 had been removed from the original version. Instead, Intel's upcoming SIMD model AVX has been adopted, which can now provide 256-bit wide registers instead of 128-bit wide registers (as provided for in SSE5). Apparently they didn't want a second 3DNow! -Experience disaster. Back then (1998) AMD had already tried to establish its own SIMD extension, which was incompatible with Intel, but which could not prevail against Intel's SSE.

In the original version of the specifications, Intel's AVX contained FMA operations in 4-operand form ( FMA4 ). AMD adopted this specification. In the latest Intel AVX specification from January 2009, however, nothing more can be read about FMA4. AMD will also support the new FMA3 commands, but will not delete the originally planned FMA4 commands and continue to make them available.

Web links

Individual evidence

  1. ↑ AMD's bulldozer with SSE5 - Planet 3DNow! - The online magazine for the AMD user. In: planet3dnow.de. Retrieved July 26, 2011 .
  2. ↑ AMD Techblog, Striking a Balance - AMD Developer Central , May 6, 2009
  3. ↑ AMD confirms: Bulldozer architecture postponed to 2011 - Planet 3DNow! - The online magazine for the AMD user. In: planet3dnow.de. Retrieved July 26, 2011 .
  4. ↑ Intel AVX Programming Reference , March 2008  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Dead Link / softwarecommunity.intel.com  
  5. ↑ Intel Advanced Vector Extensions Programming Reference , January 2009
  6. ↑ AMD's SSE5 is dead - long live AVX processors - Planet 3DNow! Forum. In: planet3dnow.de. Retrieved July 26, 2011 .