The XOP (eXtended Operations) instruction set, announced by AMD on May 1, 2009, is an extension to the 128-bit SSE core instructions in the x86 and AMD64 instruction set for the Bulldozer processor core, which was released on October 12, 2011. However AMD removed support for XOP from Zen (microarchitecture) onward. The XOP instruction set contains several different types of vector instructions since it was originally intended as a major upgrade to SSE. Most of the instructions are integer instructions, but it also contains floating point permutation and floating point fraction extraction instructions.
Used for : AMD APU, AMD Athlon, AMD FX, AMD Opteron, AMD Sempron