A bug fix in the 8086 microprocessor, revealed in the die's silicon

The 8086 microprocessor was a groundbreaking processor introduced by Intel in 1978. It led to the x86 architecture that still dominates de...

A bug fix in the 8086 microprocessor, revealed in the die's silicon A bug fix in the 8086 microprocessor, revealed in the die's silicon The 8086 microprocessor was a groundbreaking processor introduced by Intel in 1978. It led to the x86 architecture that still dominates desktop and server computing. While reverse-engineering the 8086 from die photos, a particular circuit caught my eye because its physical layout on the die didn't match the surrounding circuitry. This circuit turns out to implement special functionality for a couple of instructions, subtlely changing the way they interacted wi

related reading

• Reverse-engineering the 8086's Arithmetic/Logic Unit from die photosrighto.com
• Ken Shirriff's blogrighto.com
• A fundamental introduction to x86 assembly programmingnayuki.io
• Blog: Zen and the Art of Microcode Hackingbughunters.google.com
• 84—2484-24.org
• Zenbleedlock.cmpxchg8b.com
• The "Basics" | Putting the "You" in CPUcpu.land
• The little book about OS developmentlittleosbook.github.io
• Microprocessor - Wikipediaen.wikipedia.org
• The time the x86 emulator team found code so bad that they fixed it during emulationdevblogs.microsoft.com
• Guide to x86 Assemblyflint.cs.yale.edu
• Who ordered memory fences on an x86? | Bartosz Milewski's Programming Cafebartoszmilewski.com