On Mon, May 6, 2024 at 2:27 PM Toon Moene <t...@moene.org> wrote: > > I have now, for some time, ran LAPACK's test programs on my gcc/gfortran > builds on both on the x86_64-linux-gnu architecture, as well as the > aarch64-linux-gnu one (see, e.g., > http://moene.org/~toon/lapack-amd64-gfortran13-O3). > > The results are rather alarming - this is r15-202 for aarch64 vs r15-204 > for x86_64 (compiled with -O3):
Did you test x86_64 with -march=native (or with -mfma) or just -O3? The reason why I am asking is aarch64 includes FMA by default while x86_64 does not. Most recent x86_64 includes an FMA instruction but since the base ISA does not include it, it is not enabled by default. I am suspect the aarch64 "excessive exceeding the threshold for errors" are all caused by the more use of FMA rather than anything else. Thanks, Andrew Pinski > > diff lapack-amd64-gfortran15-O3 lapack-aarch64-gfortran15-O3 > > 3892,3895c3928,3931 > < REAL 1327023 0 (0.000%) 0 > (0.000%) > < DOUBLE PRECISION 1300917 6 (0.000%) 0 > (0.000%) > < COMPLEX 786775 0 (0.000%) 0 > (0.000%) > < COMPLEX16 787842 0 (0.000%) 0 > (0.000%) > --- > > REAL 1317063 71 (0.005%) 0 > (0.000%) > > DOUBLE PRECISION 1318331 54 (0.004%) 4 > (0.000%) > > COMPLEX 767023 390 (0.051%) 0 > (0.000%) > > COMPLEX16 772338 305 (0.039%) 0 > (0.000%) > 3897c3933 > < --> ALL PRECISIONS 4202557 6 (0.000%) 0 > (0.000%) > --- > > --> ALL PRECISIONS 4174755 820 (0.020%) 4 > (0.000%) > > Note the excessive exceeding the threshold for errors on the aarch64 > side (>). > > Of course, this is only an excerpt of the full log file - there is more > information in it to zoom in on the errors on the aarch64 side (note > that the x86_64 side is not faultless). > > Is there a way to pass this information to our websites, so that we do > not "forget" this - or in the alternative, follow the progress in > solving this ? > > Kind regards, > > -- > Toon Moene - e-mail: t...@moene.org - phone: +31 346 214290 > Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
