From: Sergei Trofimovich <siarheit@google.com>
Date: Sun, 6 Sep 2020 11:13:54 +0000 (+0100)
Subject: gcov: fix TOPN streaming from shared libraries
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4ecf368f4b4223fb2df4f3887429dfbb48852e38;p=gcc.git

gcov: fix TOPN streaming from shared libraries

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.
---

diff --git a/libgcc/libgcov-driver.c b/libgcc/libgcov-driver.c
index 58914268d4e..e53e4dc392a 100644
--- a/libgcc/libgcov-driver.c
+++ b/libgcc/libgcov-driver.c
@@ -424,7 +424,7 @@ write_one_data (const struct gcov_info *gi_ptr,
 
 	  n_counts = ci_ptr->num;
 
-	  if (gi_ptr->merge[t_ix] == __gcov_merge_topn)
+	  if (t_ix == GCOV_COUNTER_V_TOPN || t_ix == GCOV_COUNTER_V_INDIR)
 	    write_top_counters (ci_ptr, t_ix, n_counts);
 	  else
 	    {