libm for doubles -- how much effort is needed?

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As here are also some great AVR Freaks ;-), I'd like also post this here, and not only on the libc-avr-dev.
Maybe someone can help, has hints or....

currently I have to do an estimation how much time it will take to
implement double maths to the avr-libm. Based on the outcoming
estimation, it might happen that the company will sponsor this.

Well, I have no idea, how much work the adaption of the GCC will be, and
-- beside the implementation of the math itself --.

So does someone have some pointers for me? Or maybe someone already
thought about that? How much work was the "float" libm?

Thanks for helping...

coldtobi
http://blog.coldtobi.de

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Well I'd start by looking at the 32 bit IEEE754 support. To flesh this out to 64 bits should (?) be as simple as extending it to do more shifting through more registers. As it stands the freely available source handles the 8 bit exponent and 23 bit mantissa format of IEEE754 and would need to be extended to the 11 bit exponent and 52 bit mantissa of the 64 bit variant.

Cliff

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I have no ide at all as to the time needed to do the implementation proper, but I do have this advice: Estimate at least twice the time for testing as for implementing proper.

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