On Feb 15, 10:40 am, Carl Jokl <[email protected]> wrote: > Is the x87 the most accurate general purpose floating point unit on > the market?
This is the way I understand it: - Floating point data cannot be represented accurately as base-2 (divided in significand and exponent). - IEEE 754 specifies floating point standard representation and operations with 64 bit double precision. - x87 tries to minimize the epsilon by internally computing with 80 bit extended precision. - Other architectures operate with internal double precision resulting in greater epsilon (loss of precision). - You can instruct the x87 compiler to bypass extended precision mode (that's what the strictfp Java keyword does). - This bypass only applies to the significand, not the exponent - thus true IEE 754 interoperability cannot be achieved. Am I wrong? > Part of the confusion is that the x86 family of chips is generally > considered the old school legacy platform and other processors > differentiate themselves on "being x amount more efficient than legacy > x86 architecture" however the x86 can still have advantages sometimes. AFAIK the x87 may be old school, but 1) we have SSE/SSE2 to accelerate quadruple precision calculations and 2) other CPU's like the Cell is inferior to the x87 as it trades in precision for speed (which doesn't matter much when you work on vertex matrices for games). -- You received this message because you are subscribed to the Google Groups "The Java Posse" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/javaposse?hl=en.
