Reverse-engineering the Intel 8087's tangent algorithm: more than CORDIC (righto.com)
43 points by pwg 46 days ago | 4 comments

kens 46 days ago [–]

Author here for your 8087 questions...

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jaygreco 46 days ago [–]

Love these deep dives. It’s fascinating to see how real, low-level engineering we all take for granted today unfolded. It’s incredible that the rough equivalent of an entire 160lb digital computer was built and baked into silicon.Also incredible reverse engineering. In a time when seemingly all appreciation for expertise is gone it’s so refreshing to see.

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drob518 46 days ago [–]

The combination of numerical methods and low-level hardware is fascinating. Those 20th century engineers were both smart and creative.

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cmovq 46 days ago [–]

Always thought it was strange that fptan also pushes 1 to the register stack. It now makes sense it’s to retain comparability with the 8087 which returned x and y separately and required the extra division

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