System and method for extraction, alignment and decoding of CISC instructions into a nano-instruction bucket for execution by a RISC computer
US5438668A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1992 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Mar 31, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3853
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and method for extracting complex, variable length computer instructions from a stream of complex instructions each subdivided into a variable number of instructions bytes, and aligning instruction bytes of individual ones of the complex instructions. The system receives a portion of the stream of complex instructions and extracts a first set of instruction bytes starting with the first instruction bytes, using an extract shifter. The set of instruction bytes are then passed to an align latch where they are aligned and output to a next instruction detector. The next instruction detector determines the end of the first instruction based on said set of instruction bytes. An extract shifter is used to extract and provide the next set of instruction bytes to an align shifter which aligns and outputs the next instruction. The process is then repeated for the remaining instruction bytes in the stream of complex instructions. The isolated complex instructions are decoded into nano-instructions which are processed by a RISC processor core.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.