On Thu, Nov 23, 2023 at 2:47 PM Sebastian Huber
<sebastian.hu...@embedded-brains.de> wrote:
>
> gcc/ChangeLog:
> PR tree-optimization/112678
>
> * tree-profile.cc (tree_profiling): Do not use atomic operations
> for -fprofile-update=single.
> ---
> gcc/tree-profile.cc | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/gcc/tree-profile.cc b/gcc/tree-profile.cc
> index 1ac0fdb3bc98..9c8fdb8b18f4 100644
> --- a/gcc/tree-profile.cc
> +++ b/gcc/tree-profile.cc
> @@ -767,6 +767,7 @@ tree_profiling (void)
> = HAVE_sync_compare_and_swapsi || HAVE_atomic_compare_and_swapsi;
> bool have_atomic_8
> = HAVE_sync_compare_and_swapdi || HAVE_atomic_compare_and_swapdi;
> + bool needs_split = gcov_type_size == 8 && !have_atomic_8 && have_atomic_4;
> if (!can_support_atomic)
> {
> if (gcov_type_size == 4)
> @@ -775,6 +776,9 @@ tree_profiling (void)
> can_support_atomic = have_atomic_8;
> }
>
> + if (flag_profile_update != PROFILE_UPDATE_SINGLE && needs_split)
> + counter_update = COUNTER_UPDATE_ATOMIC_PARTIAL;
> +
I wonder if it's cleaner to set can_support_atomic when we can support
it with splitting instead, avoiding a != PROFILE_UPDATE_SINGLE check
here?
Otherwise looks OK.
Richard.
> if (flag_profile_update == PROFILE_UPDATE_ATOMIC
> && !can_support_atomic)
> {
> @@ -788,13 +792,11 @@ tree_profiling (void)
>
> if (flag_profile_update == PROFILE_UPDATE_ATOMIC)
> {
> - if (gcov_type_size == 8 && !have_atomic_8 && have_atomic_4)
> + if (needs_split)
> counter_update = COUNTER_UPDATE_ATOMIC_SPLIT;
> else
> counter_update = COUNTER_UPDATE_ATOMIC_BUILTIN;
> }
> - else if (gcov_type_size == 8 && have_atomic_4)
> - counter_update = COUNTER_UPDATE_ATOMIC_PARTIAL;
>
> /* This is a small-ipa pass that gets called only once, from
> cgraphunit.cc:ipa_passes(). */
> --
> 2.35.3
>
