학술논문

Decoupling integer execution in superscalar processors
Document Type
Conference
Source
Proceedings of the 28th Annual International Symposium on Microarchitecture Microarchitecture Microarchitecture, 1995., Proceedings of the 28th Annual International Symposium on. :285-290 Dec, 1995
Subject
Components, Circuits, Devices and Systems
Registers
Microarchitecture
Microprocessors
Computer aided instruction
Hardware
Bandwidth
Feeds
Computer architecture
Decoding
Coprocessors
Language
ISSN
1072-4451
Abstract
We propose that processor hardware can be used more effectively if floating-point units are augmented to perform simple integer operations. Existing floating-point registers and datapaths are used to support these integer operations. Some integer instructions, those not used for computing addresses and accessing memory, can then be off-loaded to the floating-point units. Consequently, these integer instructions are decoupled from memory accessing, and additional instruction bandwidth is available for integer programs. This paper reports the results of a preliminary study of integer benchmark programs compiled for the SPARC architecture. The results indicate that between 10% and 39% of the instructions in the integer benchmarks can be executed in the augmented floating-point units. Furthermore, these instructions are all simple add, subtract and logical instructions.