[PATCH] gcov: add info about "calls" to JSON output format

["Martin Liška" <mliska@suse.cz>]

Patch can bootstrap on x86_64-linux-gnu and survives regression tests.

Ready to be installed after stage1 opens?

Thanks,
Martin

gcc/ChangeLog:

	* doc/gcov.texi: Document the new "calls" field and document
	the API bump.
	* gcov.cc (output_intermediate_json_line): Output info about
	calls.
	(generate_results): Bump version to 2.

gcc/testsuite/ChangeLog:

	* g++.dg/gcov/gcov-17.C: Add call to a noreturn function.
	* g++.dg/gcov/test-gcov-17.py: Cover new format.
	* lib/gcov.exp: Add options for gcov that emit the extra info.
---
 gcc/doc/gcov.texi                         | 27 +++++++++++++++++++++--
 gcc/gcov.cc                               | 12 +++++++++-
 gcc/testsuite/g++.dg/gcov/gcov-17.C       |  7 ++++++
 gcc/testsuite/g++.dg/gcov/test-gcov-17.py | 17 ++++++++++----
 gcc/testsuite/lib/gcov.exp                |  2 +-
 5 files changed, 57 insertions(+), 8 deletions(-)

diff --git a/gcc/doc/gcov.texi b/gcc/doc/gcov.texi
index d39cce3a683..6739ebb3643 100644
--- a/gcc/doc/gcov.texi
+++ b/gcc/doc/gcov.texi
@@ -195,7 +195,7 @@ Structure of the JSON is following:
 @{
   "current_working_directory": "foo/bar",
   "data_file": "a.out",
-  "format_version": "1",
+  "format_version": "2",
   "gcc_version": "11.1.1 20210510"
   "files": ["$file"]
 @}
@@ -214,6 +214,12 @@ a compilation unit was compiled
 @item
 @var{format_version}: semantic version of the format
 
+Changes in version @emph{2}:
+@itemize @bullet
+@item
+@var{calls}: information about function calls is added
+@end itemize
+
 @item
 @var{gcc_version}: version of the GCC compiler
 @end itemize
@@ -292,6 +298,7 @@ Each @var{line} has the following form:
 @smallexample
 @{
   "branches": ["$branch"],
+  "calls": ["$call"],
   "count": 2,
   "line_number": 15,
   "unexecuted_block": false,
@@ -299,7 +306,7 @@ Each @var{line} has the following form:
 @}
 @end smallexample
 
-Branches are present only with @var{-b} option.
+Branches and calls are present only with @var{-b} option.
 Fields of the @var{line} element have following semantics:
 
 @itemize @bullet
@@ -341,6 +348,22 @@ Fields of the @var{branch} element have following semantics:
 @var{throw}: true when the branch is an exceptional branch
 @end itemize
 
+Each @var{call} has the following form:
+
+@smallexample
+@{
+  "returned": 11,
+@}
+@end smallexample
+
+Fields of the @var{call} element have following semantics:
+
+@itemize @bullet
+@item
+@var{returned}: number of times a function call returned (call count is equal
+to @var{line::count})
+@end itemize
+
 @item -H
 @itemx --human-readable
 Write counts in human readable format (like 24.6k).
diff --git a/gcc/gcov.cc b/gcc/gcov.cc
index 2ec7248cc0e..88324143640 100644
--- a/gcc/gcov.cc
+++ b/gcc/gcov.cc
@@ -1116,6 +1116,9 @@ output_intermediate_json_line (json::array *object,
   json::array *branches = new json::array ();
   lineo->set ("branches", branches);
 
+  json::array *calls = new json::array ();
+  lineo->set ("calls", calls);
+
   vector<arc_info *>::const_iterator it;
   if (flag_branches)
     for (it = line->branches.begin (); it != line->branches.end ();
@@ -1130,6 +1133,13 @@ output_intermediate_json_line (json::array *object,
 			 new json::literal ((*it)->fall_through));
 	    branches->append (branch);
 	  }
+	else if ((*it)->is_call_non_return)
+	  {
+	    json::object *call = new json::object ();
+	    gcov_type returns = (*it)->src->count - (*it)->count;
+	    call->set ("returned", new json::integer_number (returns));
+	    calls->append (call);
+	  }
       }
 
   object->append (lineo);
@@ -1523,7 +1533,7 @@ generate_results (const char *file_name)
   gcov_intermediate_filename = get_gcov_intermediate_filename (file_name);
 
   json::object *root = new json::object ();
-  root->set ("format_version", new json::string ("1"));
+  root->set ("format_version", new json::string ("2"));
   root->set ("gcc_version", new json::string (version_string));
 
   if (bbg_cwd != NULL)
diff --git a/gcc/testsuite/g++.dg/gcov/gcov-17.C b/gcc/testsuite/g++.dg/gcov/gcov-17.C
index d11883cfd39..efe019599a5 100644
--- a/gcc/testsuite/g++.dg/gcov/gcov-17.C
+++ b/gcc/testsuite/g++.dg/gcov/gcov-17.C
@@ -15,6 +15,11 @@ private:
 template class Foo<int>;
 template class Foo<char>;
 
+static void noret()
+{
+  __builtin_exit (0);
+}
+
 int
 main (void)
 {
@@ -34,6 +39,8 @@ main (void)
     __builtin_printf ("Failure\n");
   else
     __builtin_printf ("Success\n");
+
+  noret ();
   return 0;
 }
 
diff --git a/gcc/testsuite/g++.dg/gcov/test-gcov-17.py b/gcc/testsuite/g++.dg/gcov/test-gcov-17.py
index ec5df3dec03..a0b8b09b85c 100644
--- a/gcc/testsuite/g++.dg/gcov/test-gcov-17.py
+++ b/gcc/testsuite/g++.dg/gcov/test-gcov-17.py
@@ -12,7 +12,7 @@ def test_basics(gcov):
     files = gcov['files']
     assert len(files) == 1
     functions = files[0]['functions']
-    assert len(functions) == 5
+    assert len(functions) == 6
 
 
 def test_lines(gcov):
@@ -31,7 +31,16 @@ def test_lines(gcov):
     assert line9[1]['count'] == 2
     assert line9[0]['unexecuted_block']
     assert not line9[1]['unexecuted_block']
-    assert linesdict[31][0]['unexecuted_block']
-    assert linesdict[34][0]['unexecuted_block']
-    assert not linesdict[37][0]['unexecuted_block']
+    assert linesdict[36][0]['unexecuted_block']
+    assert linesdict[39][0]['unexecuted_block']
+    assert not linesdict[41][0]['unexecuted_block']
     assert 32 not in linesdict
+    print(lines)
+
+    line41 = linesdict[41][0]
+    assert line41['count'] == 1
+    assert line41['calls'] == [{'returned': 1}]
+
+    line43 = linesdict[43][0]
+    assert line43['count'] == 1
+    assert line43['calls'] == [{'returned': 0}]
diff --git a/gcc/testsuite/lib/gcov.exp b/gcc/testsuite/lib/gcov.exp
index 80e74aeb220..e5e94fa5a76 100644
--- a/gcc/testsuite/lib/gcov.exp
+++ b/gcc/testsuite/lib/gcov.exp
@@ -274,7 +274,7 @@ proc run-gcov-pytest { args } {
 
     verbose "Running $GCOV $testcase in $srcdir/$subdir" 2
     set testcase [remote_download host $testcase]
-    set result [remote_exec host $GCOV "$testcase -i"]
+    set result [remote_exec host $GCOV "$testcase -i -abc"]
 
     set pytest_script [lindex $args 1]
     if { ![check_effective_target_pytest3] } {
-- 
2.40.0