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A comment on Extracting ROM constants from the 8087 math coprocessor's die. Parent comment

Re:Extracting ROM constants from the 8087 math coprocessor's... by bonzini on Saturday May 16, 2020 @03:29PM (#23206476)
Ken, could the two 10^18 constants have two different signs? The signs must be stored somewhere like the exponents. Since most bits are zero for both signs and exponents, does it make sense for them to be coded as Boolean functions instead of being stored in a ROM?
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Re:Extracting ROM constants from the 8087 math coprocessor's... by kens on Saturday May 16, 2020 @03:41PM (#23206570)
I actually wrote that idea (two different signs) in the post but took it out :-) My thinking is that the hardware must support negation, so it would save space to have one constant and negate it instead of two constants with different signs.

I'm still investigating the chip, so I hope to find the exponent ROM (or Boolean logic as you suggest) and solve this puzzle.

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