On Mon, Dec 5, 2022 at 8:26 AM Sebastian Huber <sebastian.hu...@embedded-brains.de> wrote: > > On 08/11/2022 11:25, Richard Biener wrote: > >> It would be great to have a code example for the construction of the "if > >> (f()) f();". > > I think for the function above we need to emit __atomic_fetch_add_8, > > not the emulated form because we cannot insert the required control > > flow (if (f()) f()) on an edge. The __atomic_fetch_add_8 should then be > > lowered after the instrumentation took place. > > Would it help to change the > > if (__atomic_add_fetch_4 ((unsigned int *) &val, 1, __ATOMIC_RELAXED) > == 0) > __atomic_fetch_add_4 (((unsigned int *) &val) + 1, 1, > __ATOMIC_RELAXED); > > into > > unsigned int v = __atomic_add_fetch_4 ((unsigned int *) &val, 1, > __ATOMIC_RELAXED) > == 0) > v = (unsigned int)(v == 0); > __atomic_fetch_add_4 (((unsigned int *) &val) + 1, 1, > __ATOMIC_RELAXED);
that's supposed to add 'v' instead of 1? Possibly use uint32_t here (aka uint32_type_node). > > to get rid of an inserted control flow? That for sure wouldn't require any changes to how the profile instrumentation works, so yes it would be simpler. Richard. > On riscv this is optimized to: > > li a4,1 > amoadd.w a5,a4,0(a0) > addi a5,a5,1 > seqz a5,a5 > addi a4,a0,4 > amoadd.w zero,a5,0(a4) > > > -- > embedded brains GmbH > Herr Sebastian HUBER > Dornierstr. 4 > 82178 Puchheim > Germany > email: sebastian.hu...@embedded-brains.de > phone: +49-89-18 94 741 - 16 > fax: +49-89-18 94 741 - 08 > > Registergericht: Amtsgericht München > Registernummer: HRB 157899 > Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler > Unsere Datenschutzerklärung finden Sie hier: > https://embedded-brains.de/datenschutzerklaerung/
