[LCP]Rounding questions

Chuck Martin nrocinu at myrealbox.com
Sat Sep 7 06:41:09 UTC 2002


On Fri, Sep 06, 2002 at 10:32:49AM +0100, Vincent Penquerc'h wrote:
> It might be because of some optimization done by the compiler.
> Which might include moving around fp values from an FPU register
> to and from memory. On i386, FPU registers have better precision
> that the memory they are stored in, so if you move something from
> FPU to mem, then from mem to FPU, the value will have changed.
> This *may* be (part of) the problem.

Yes, I've come across that once before, and I thought about it as
a possibility, but didn't know how to test it.  I didn't think
about it being related to optimisation, though.  It looks like
you may be right.

Chuck





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