This is a quite interesting presentation on Intel CPU secrets:
Microcode is an abstraction layer on top of the physical components of a CPU and present in most general-purpose CPUs today. While it is well-known that CPUs feature a microcode update mechanism, very little is known about its inner workings given that microcode and the update mechanism itself are proprietary and have not been throughly analyzed yet. We close this gap by both analyzing microcode and writing our own programs for it.
5 Comments
Tomi Engdahl says:
https://hackaday.com/2021/02/25/oddball-x86-instructions/
Tomi Engdahl says:
https://fanael.github.io/is-x86-risc-internally.html
Tomi Engdahl says:
https://hackaday.com/2023/07/17/finding-undocumented-8086-instructions-via-microcode/
Tomi Engdahl says:
Intel’s First x86 CPU Had Secret Instructions Meant to Catch IP Thievery
By Francisco Pires published 9 days ago
Expensive transistors meant some security venues were left almost unguarded.
https://www.tomshardware.com/news/intels-first-x86-cpu-had-secret-instructions-meant-to-catch-ip-thievery
Tomi Engdahl says:
Tracing the roots of the 8086 instruction set to the Datapoint 2200 minicomputer
https://www.righto.com/2023/08/datapoint-to-8086.html