On Mon, Mar 31, 2025 at 7:54 PM Jørgen Kvalsvik <j...@lambda.is> wrote:
>
> gcov_write_* functions must be guarded so they only are called when
> output_to_file is true, like for -fcondition-coverage, otherwise it
> triggers an invalid read as detected by valgrind. The gcno file is
> mostly written to from profile.cc, so it doesn't make too much sense
> to hide it in path-coverage.cc. The find_paths name was a bit
> imprecise, and is renamed to instrument_prime_paths.
OK.
Richard.
> PR gcov-profile/119553
>
> gcc/ChangeLog:
>
> * path-coverage.cc (find_paths): Return path count, don't
> write to gcno, and rename to ...
> (instrument_prime_paths): ... this.
> * profile.cc (branch_prob): Write path counts to gcno.
> ---
> gcc/path-coverage.cc | 15 ++++++---------
> gcc/profile.cc | 12 ++++++++++--
> 2 files changed, 16 insertions(+), 11 deletions(-)
>
> diff --git a/gcc/path-coverage.cc b/gcc/path-coverage.cc
> index 55b39298603..55058fd04ff 100644
> --- a/gcc/path-coverage.cc
> +++ b/gcc/path-coverage.cc
> @@ -504,8 +504,8 @@ flush_on_gsi (gimple_stmt_iterator *gsi, size_t bucket,
> tree local, tree mask,
> bit N%64 in bucket N/64. For large functions, an individual basic block
> will only be part of a small subset of paths, and by extension buckets and
> local counters. Only the necessary counters are read and written. */
> -void
> -find_paths (struct function *fn)
> +unsigned
> +instrument_prime_paths (struct function *fn)
> {
> mark_dfs_back_edges (fn);
> vec<vec<int>> paths = find_prime_paths (fn);
> @@ -515,7 +515,7 @@ find_paths (struct function *fn)
> warning_at (fn->function_start_locus, OPT_Wcoverage_too_many_paths,
> "paths exceeding limit, giving up path coverage");
> release_vec_vec (paths);
> - return;
> + return 0;
> }
>
> tree gcov_type_node = get_gcov_type ();
> @@ -526,14 +526,9 @@ find_paths (struct function *fn)
> if (!coverage_counter_alloc (GCOV_COUNTER_PATHS, nbuckets))
> {
> release_vec_vec (paths);
> - return;
> + return 0;
> }
>
> - gcov_position_t offset {};
> - offset = gcov_write_tag (GCOV_TAG_PATHS);
> - gcov_write_unsigned (paths.length ());
> - gcov_write_length (offset);
> -
> hash_map <edge_hash, uint64_t> ands;
> hash_map <block_hash, uint64_t> iors;
> hash_map <block_hash, uint64_t> flushes;
> @@ -771,6 +766,8 @@ find_paths (struct function *fn)
> }
> }
>
> + const unsigned npaths = paths.length ();
> blocks.release ();
> release_vec_vec (paths);
> + return npaths;
> }
> diff --git a/gcc/profile.cc b/gcc/profile.cc
> index 0b222cf3864..c0f5097726b 100644
> --- a/gcc/profile.cc
> +++ b/gcc/profile.cc
> @@ -1611,9 +1611,17 @@ branch_prob (bool thunk)
> instrument_values (values);
> }
>
> - void find_paths (struct function*);
> + unsigned instrument_prime_paths (struct function*);
> if (path_coverage_flag)
> - find_paths (cfun);
> + {
> + const unsigned npaths = instrument_prime_paths (cfun);
> + if (output_to_file)
> + {
> + gcov_position_t offset = gcov_write_tag (GCOV_TAG_PATHS);
> + gcov_write_unsigned (npaths);
> + gcov_write_length (offset);
> + }
> + }
>
> free_aux_for_edges ();
>
> --
> 2.39.5
>
