On 2019-01-16 18:08, Alex Bennée wrote: > > Thomas Huth <th...@redhat.com> writes: > >> On 2019-01-15 21:05, Emilio G. Cota wrote: >>> On Tue, Jan 15, 2019 at 16:01:32 +0000, Alex Bennée wrote: >>>> Ahh I should have mentioned we already have the technology for this ;-) >>>> >>>> If you build the fpu/next tree on a s390x you can then run: >>>> >>>> ./tests/fp/fp-bench f64_div >>>> >>>> with and without the CONFIG_128 path. To get an idea of the real world >>>> impact you can compile a foreign binary and run it on a s390x system >>>> with: >>>> >>>> $QEMU ./tests/fp/fp-bench f64_div -t host >>>> >>>> And that will give you the peak performance assuming your program is >>>> doing nothing but f64_div operations. If the two QEMU's are basically in >>>> the same ballpark then it doesn't make enough difference. That said: >>> >>> I think you mean here `tests/fp/fp-bench -o div -p double', otherwise >>> you'll get the default op (-o add). >> >> I tried that now, too, and -o div -p double does not really seem to >> exercise this function at all. > > How do you mean? It should do because by default it should be calling > the softfloat implementations.
I've added a puts("hello") into the udiv_qrnd() function. When I then run "fp-bench -o div -p double", it only prints out "hello" a single time, so the function is only called once during the whole test. Thomas