Re: [ros-kernel] 64-bit integers

[Kohn E. D. <em...@cs...>]

Hi Brian,

The problem with 64 bit divisions on the 32 bit x86 architecture is that
the processor provides support only for dividing a 64 bit number by a 32
bit number. In this case you need just a single instruction. However, if
the divisor is 64 bit (i.e. its most significant 32 bits are not all
zero), things go messy. As far as I know, all 32 bit compilers rely on a
library routine for 64 bit division. So I think you will have to copy the
routine from the runtime library.


								Emil


On Sun, 28 Jul 2002, Brian Palmer wrote:

> I would like to start using 64-bit integers in FreeLoader. But when I do
> a 64-bit divide it doesn't seem to just generate a couple instructions
> to do it. Instead it seems to call __udivdi3. Now since I do not use
> standard headers or link against standard C-runtime libraries I do not
> get this function. I am using DJGPP currently, and I do not know if
> Mingw32 uses this crap also. Does anyone know if there is any way to get
> around using this function or am I just going to have to copy it from
> the compiler source?
>
> Brian
>