Performance and Assembly Language Programming of the iPSC/860 System

In the world of supercomputers, the goal is higher and higher performance. To obtain the highest performance on a particular computational kernel, it is usually necessary to write assembly language. Compiler technology has not matured to the point of being able to take advantage many of the features of the i860 automatically. To approach the peak performance of the chip, it is currently necessary to use custom assembly language code. It is important to know which combinations of assembly instructions offer the highest performance, and which combinations cannot run at full speed. This paper assumes that you are already acquainted with the basics of the i860 microprocessor assembly language, and concentrates on describing how to enhance the performance of your code using 860 assembly language.