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Re: libjava configure question
Bryce McKinlay writes:
> Andrew Haley wrote:
> >Tom Tromey writes:
> > > >>>>> "Andrew" == Andrew Haley <firstname.lastname@example.org> writes:
> > >
> > > Andrew> One other thing: I don't think we can do this in
> > > Andrew> general and meet even the more relaxed requirements of
> > > Andrew> java.lang.Math, because the x86 has a restricted range
> > > Andrew> of allowable arguments to its trig functions.
> > >
> > > I thought the Math restrictions were designed to explicitly allow use
> > > of the FPU on x86.
> >Yes, but not without some wrapper code. The crucial issue here is
> >full range reduction, and the floating-point instructions don't do
> >that by themselves.
> I'm sure the math library functions do, though - we'd still likely
> get a performance improvement from using those directly, even
> without inlining of FP instructions - since they'll be optimized
> for each architecture.
Yes, that's probably true. We'd have to make sure that calls to
java::lang::Math::sin() etc. were replaced by sin() and we'd also have
either to remove our own definitions of the functions or make them
All quite possible, but perhaps not top of the list.