Speculating the entire x86-64 instruction set in seconds with one weird trick
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2007–2026One slot for every year since HN launched. Height is that year's peak points; orange marks a 100+ point or 50+ comment breakout. Select a bar to open its strongest thread.
Top comments
This is a really clever technique! I was impressed by sandsifter[1] when it originally came out, and this seems an awful lot faster and less prone to false negatives (since it's purely speculative and doesn't require sandsifter's `#PF` hack). At the risk of unwarranted self-promotion: the other side of this equation is fidelity in software instruction set decoders. x86's massive size and layers of historical complexity make it among the most difficult instruction formats to accurately decode; I've spent a…
Could they do this with x86-16?
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HN stats
- Breakout years
- 2
- Total points
- 330
- Total comments
- 69
100+ points or 50+ comments
reference only — not used in Hall rules or ranking
reference only — not used in Hall rules or ranking
Every submission
| Date | Title as submitted | By | Points | Comments |
|---|---|---|---|---|
| 2021-03-23 | Speculating the Entire x86-64 Instruction Set in Seconds | 6thsurvivor | 5 | 0 |
| 2021-03-23 | Speculating the Entire x86-64 Instruction Set with This One Weird Trick | ruik | 4 | 0 |
| 2021-03-24 | Speculating the Entire x86-64 Instruction Set in Seconds | notamy | 2 | 0 |
| 2021-03-25 | Speculating the Entire x86-64 Instruction Set in Seconds | zx2c4 | 7 | 0 |
| 2021-03-25 | Speculating the entire x86-64 instruction set in seconds with one weird trickFirst breakout · Best thread | muricula | 208 | 65 |
| 2024-05-14 | Speculating the entire x86-64 instruction set in seconds (2021)Latest 20+ point return | fanf2 | 104 | 4 |