Tracing the roots of the 8086 instruction set to the Datapoint 2200 minicomputer righto.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from righto.com Daily Mail and Mail on Sunday newspapers.
CPU fun
Who really designed this processor?
Introduction
This time around I’m going to look at high-resolution timers and a few oddities in the way the x86 64 emulation on the M1 presents itself, that lead to some potential “gotchas”.
I’ve created a small program to demonstrate the issues I discuss here, which you can download to run yourself. It’s
(e.g.
src/stats-timing.cc which is itself used by the micro-benchmarks in the LOMP
Why Worry About Timers?
For micro-benchmarks it is useful to have high-resolution, low-overhead timers, ideally ones which we can access in a single instruction. While the most portable thing to do is to use the