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A comment on Two interesting XOR circuits inside the Intel 386 processor. Parent comment

Re:Two interesting XOR circuits inside the Intel 386 processor by ksaj on Saturday December 16, 2023 @06:13PM (#38668694)
If you do a writeup on the prefetch queue and want some original code for tampering with it, let me know. I did some deep experimentation with it in the 90's, and still have the code archived.

The prefetch queue could be (ab)used in some very interesting and sometimes baffling ways. One of the creations causes a divide by zero if you try to debug it, even if viewing the code doesn't look like it should.

Also, I did some experimenting with shrinking code by replacing INT3h with INT21h (one byte, versus two), which similarly lent itself to anti-debugger effects.

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Re:Two interesting XOR circuits inside the Intel 386 processor by kens on Saturday December 16, 2023 @07:28PM (#38669200)
It sounds like you did some very interesting experimentation with the prefetch queue. Realistically, I'm unlikely to investigate the 386 prefetch queue to that level of detail, but if I do, your tests would be useful.
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