AMD announces SSE5 extensions to x86 architecture
Posted by marc, Fri Aug 31 13:10:54 UTC 2007
Wow, years after RISC did it, AMD is bringing SIMD to the x86 architecture. They announced their "SSE5" called extention to the x86 architecture.
Until now, the x86 platform had the major drawback of having a maximum of only two operands in their instructions. The G4 CPUs have an extention called "Altivec" which is comparable to SSE5 (and has been there for years).
To quote arstechnica:
Here is SSE5 in comparison to "other" SSEs
The official PDF
The official developer Page
An article describing SIMD and the x86 shortcomings
A Forum thread dealing with it
via arstechnica
In a nutshell, a third operand lets a programmer or compiler specify a filter/mod register that can affect the way that a vector operation is carried out on the operands in the other two registers. Such operands are extremely useful for doing in a single instruction a variety of operations that would normally take a sequence of multiple instructions. The use of a third operand register can significantly increase performance for some types of codes, especially in hand-tuned code.A little information: SIMD means "Single Instruction Multiple Data"
![SIMD](http://marc-seeger.de/2007/08/simd.thumbnail.gif)
![SSE5 and others](http://marc-seeger.de/2007/08/sse5-and-others.thumbnail.jpg)