review (S) for 6849984: Value methods for platform dependent math functions constant fold incorrectly
Christian.Thalinger at Sun.COM
Thu Jan 14 11:19:09 PST 2010
On Thu, 2010-01-14 at 09:45 -0800, Vladimir Kozlov wrote:
> > Maybe I missed the point of this change, but why are we using the much
> > more complicated C versions for these?
> > + // The intrinsic version of these seem to return the same value as
> > + // the strict version.
> > + StubRoutines::_intrinsic_exp = SharedRuntime::dexp;
> > + StubRoutines::_intrinsic_pow = SharedRuntime::dpow;
> There is no implementation of ExpD and PowD in x86_64.ad (which is surprise - we missed it???)
> And it is also complex code - see it in x86_32.ad
Tom just explained it to me on the phone (I try to summarize): What I
missed is that these new intrinsics are used in the compiler to do
constant folding and aren't used during runtime.
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