On: How many x86 instructions are there? (2016)

[g0xA52A2A]

How about undocumented instructions? Sandsifter[1] is an interesting project and the video from BlackHat[2] is a good watch. There's also a previous discussion of it on HN[3].

[1] https://github.com/Battelle/sandsifter

[2] https://www.youtube.com/watch?v=KrksBdWcZgQ

[3] https://news.ycombinator.com/item?id=18179212

[stevemk14ebr → g0xA52A2A]

Also see https://blog.can.ac/2021/03/22/speculating-x86-64-isa-with-o...

[g0xA52A2A → stevemk14ebr]

Ah cool, seems I missed that when it appeared on HN a few weeks back. Thanks for the pointer.

[da_big_ghey → g0xA52A2A]

yes and sansdifter are continue finding more, recent undocumented microcode modify instruction are find with it.

[sandinmyjoints → g0xA52A2A]

Very cool project! Thanks for the pointer.