Le mercredi 21 septembre 2016 à 11:36 -0700, Chris Rackauckas a écrit :
> The Windows one is using the pre-built binary. The Linux one uses the
> COPR nightly (I assume that should build with all the goodies?)
The Copr RPMs are subject to the same constraint as official binaries:
we need them to work on most machines. So they don't enable FMA (nor
e.g. AVX) either.
It would be nice to find a way to ship with several pre-built sysimg
files and using the highest instruction set supported by your CPU.
> > > Hi,
> > > First of all, does LLVM essentially fma or muladd expressions
> > > like `a1*x1 + a2*x2 + a3*x3 + a4*x4`? Or is it required that one
> > > explicitly use `muladd` and `fma` on these types of instructions
> > > (is there a macro for making this easier)?
> > >
> > You will generally need to use muladd, unless you use @fastmath.
> > > Secondly, I am wondering if my setup is no applying these
> > > operations correctly. Here's my test code:
> > >
> > If you're using the prebuilt downloads (as opposed to building from
> > source), you will need to rebuild the sysimg (look in
> > contrib/build_sysimg.jl) as we build for the lowest-common
> > architecture.
> > -Simon