[J-core] Breaking the x86 Instruction Set - Lot's of undocumented instructions found in x86 at this years black hat conference

D. Jeff Dionne Jeff at SE-Instruments.com
Fri Sep 8 22:51:51 EDT 2017


On Sep 9, 2017, at 10:29, Joh-Tob Schäg <johtobsch at gmail.com> wrote:

> ​Well you have not proven anything! You just performed an experiment which suggested that there are no faults in a small area of the source space.  Formal verification is king in the end.​ 

Exactly.  The key is what Formal means... one man's limited experiment is another man's burdensome formal verification methodology ;)

Specifically:  We think we have a necessary and sufficient set of test vectors for the J2 implementation that validates functionality.   Tests for mis-operation are in my opinion less mature for the existent J2 core.  I am satisfied, this RTL is frozen and will tape out as-is... but there is yet another pass verification pass to do still (after that).

J


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