Ideas for a simple fast VAX

Butler Lampson


Citation: Internal memo, Digital Systems Research Center, October 1985.

Links: Abstract, Acrobat. Here is an HTML version created by OCR for the benefit of search engines; it is not meant for human consumption.

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Six ideas are put together here to make a design for a 4 tpi VAX with a very short cycle time, whose basic execution engine is simpler than Nautilus. Other parts of the design will be at least as complex, so that the whole machine will not be any simpler; in fact, if it has high-performance floating-point, there will be substantial added complexity for that. The hope is that the other parts are not critical to the performance, and hence can be designed without having to squeeze out every nanosecond.