From: Sergei Trofimovich <siarh...@google.com>
Before the change gcc did not stream correctly TOPN counters
if counters belonged to a non-local shared object.
As a result zero-section optimization generated TOPN sections
in a form not recognizable by '__gcov_merge_topn'.
The problem happens because in a case of multiple shared objects
'__gcov_merge_topn' function is present in address space multiple
times (once per each object).
The fix is to never rely on function address and predicate on TOPN
counter types.
libgcc/ChangeLog:
PR gcov-profile/96913
* libgcov-driver.c (write_one_data): Avoid function pointer
comparison in TOP streaming decision.
---
libgcc/libgcov-driver.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/libgcc/libgcov-driver.c b/libgcc/libgcov-driver.c
index 58914268d4e..86a6b5ad68a 100644
--- a/libgcc/libgcov-driver.c
+++ b/libgcc/libgcov-driver.c
@@ -424,10 +424,15 @@ write_one_data (const struct gcov_info *gi_ptr,
n_counts = ci_ptr->num;
- if (gi_ptr->merge[t_ix] == __gcov_merge_topn)
+ /* Do not zero-compress top counters because:
+ * - __gcv_merge_topn does not handle such sections
+ * - GCOV_COUNTER_V_INDIR contains non-zero keys
+ */
+ if (t_ix == GCOV_COUNTER_V_TOPN || t_ix == GCOV_COUNTER_V_INDIR)
write_top_counters (ci_ptr, t_ix, n_counts);
else
{
+
/* Do not stream when all counters are zero. */
int all_zeros = 1;
for (unsigned i = 0; i < n_counts; i++)
--
2.28.0
