Dependency checking and forwarding of variable width operands
US5590352A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1994 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Apr 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/3858
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A pipelined or superscalar processor (10) that executes operations utilizing operand data of variable bit widths improves parallel performance by partitioning a fixed bit width operand (200) into several partial operand fields (215, 216 and 217), and checking for data dependencies, tagging and forwarding data in these fields independently of one another. An instruction decoder (18) concurrently dispatches multiple ROPs to various functional units (20, 21, 22 and 80). Conflicts which arise with respect to register resources are resolved through register renaming. However, implementation of register renaming is difficult when register structures are overlapping. The present invention supports independent dependency checking, tagging and forwarding of partial bit fields of a register operand which, in combination, allow renaming of registers. Therefore, the variable width register operand structure greatly assists the processor to resolve data dependencies. Operands are tagged by a reorder buffer (26) and supplied with data when it becomes available without regard for the type of data. This method of dependency resolution supports parallel performance of operations and provides a subs…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.