The other day I bumped into an AMD K6 family processor and looked it up when I got home, when I read some thing about trasnlating to a RISC like instruction set I nearly fell off my chair… Today I looked up a little more. I would guess the K6 is probably up this ally as well.
RISC86 Microarchitecture
The Nx586 processor fully implements the industry standard x86 instruction set to be able to run the more than 50,000 applications now available. This implementation is accomplished through the use of NexGen’s patented RISC86 microarchitecture. The innovative RISC86 approach dynamically translates x86 instructions into RISC86 instructions. These RISC86 instructions were specifically designed with direct support for the x86 architecture while obeying RISC performance principles. They are thus simpler and easier to execute than the complex x86 instructions. Note that this approach is fundamentally different than RISC processors, which have no support whatsoever for the x86 instruction set architecture. The RISC86 microarchitecture also contains many state-of-the-art computer science techniques to achieve very high performance, including register renaming, data forwarding, speculative execution, and out-of-order execution.
The benefits of this approach are several. First, the performance advantages of RISC design are applied to the x86 instruction set. Second, the execution unit can be smaller and more compact. Third, the execution units can be more specialized to give specific performance enhancements. Finally, it will be easier to add additional execution units in future designs. The RISC86 microarchitecture not only gives the Nx586 processor high performance today, but also allows for significantly higher performance in the future.