• LurkingLuddite@piefed.social
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    7 days ago

    Isn’t a big point of floating point that it can easily have mathematical operators done on them on CPUs? Sure, complex circuitry is no big deal these days, but IIRC, there were very good reasons for what was chosen.

    • Quetzalcutlass@lemmy.world
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      7 days ago

      One of the linked papers makes the claim that the circuitry would be less complex than that needed for floats, but also includes this note:

      Floats have one advantage over posits for the hardware designer: the fixed location of bits for the exponent and the fraction mean they can be decoded in parallel. With posits, there is a little serialization in having to determine the regime bits before the other bits can be decoded. There is a simple workaround for this in a processor design, similar to a trick used to speed the exception handling of floats: Some extra register bits can be attached to each value to save the need for extracting size information when decoding instructions.

      The proposed system also lacks NaN and separate positive/negative infinities, so it wouldn’t be a drop-in replacement.