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Re: libjava configure question

Bryce McKinlay writes:
 > Andrew Haley wrote:
 > >Tom Tromey writes:
 > > > >>>>> "Andrew" == Andrew Haley <> 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.


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