perf: set frame->f_trace_lines=0 when not tracing. ~3% faster

Author: nedbat

coverage/ctracer/tracer.c

@@ -514,6 +514,7 @@ CTracer_handle_call(CTracer *self, PyFrameObject *frame)
         Py_XDECREF(self->pcur_entry->file_data);
         self->pcur_entry->file_data = NULL;
         self->pcur_entry->file_tracer = Py_None;
+        frame->f_trace_lines = 0;
         SHOWLOG(PyFrame_GetLineNumber(frame), filename, "skipped");
     }
 

coverage/pytracer.py

@@ -161,6 +161,7 @@ def _trace(self, frame, event, arg_unused):
                 self.cur_file_data = self.data[tracename]
             else:
                 frame.f_trace_lines = False
+
             # The call event is really a "start frame" event, and happens for
             # function calls and re-entering generators.  The f_lasti field is
             # -1 for calls, and a real offset for generators.  Use <0 as the
@@ -176,6 +177,7 @@ def _trace(self, frame, event, arg_unused):
                 self.last_line = -frame.f_code.co_firstlineno
             else:
                 self.last_line = frame.f_lineno
+
         elif event == 'line':
             # Record an executed line.
             if self.cur_file_data is not None:
@@ -186,6 +188,7 @@ def _trace(self, frame, event, arg_unused):
                 else:
                     self.cur_file_data.add(lineno)
                 self.last_line = lineno
+
         elif event == 'return':
             if self.trace_arcs and self.cur_file_data:
                 # Record an arc leaving the function, but beware that a
@@ -213,6 +216,7 @@ def _trace(self, frame, event, arg_unused):
                 if real_return:
                     first = frame.f_code.co_firstlineno
                     self.cur_file_data.add((self.last_line, -first))
+
             # Leaving this function, pop the filename stack.
             self.cur_file_data, self.cur_file_name, self.last_line, self.started_context = (
                 self.data_stack.pop()

lab/benchmark.py

@@ -257,44 +257,35 @@ def run_experiments(
 
     run_experiments(
         py_versions=[
+            Python(3, 7),
             Python(3, 10),
         ],
         cov_versions=[
             ("none", None, None),
             ("6.4", "coverage==6.4", ""),
-            ("6.4 timid", "coverage==6.4", "timid=True"),
-            (
-                "PR 1381",
-                "git+https://github.com/cfbolz/coveragepy.git@f_trace_lines",
-                "",
-            ),
-            (
-                "PR 1381 timid",
-                "git+https://github.com/cfbolz/coveragepy.git@f_trace_lines",
-                "timid=True",
-            ),
+            ("tip", "-e ~/coverage/trunk", ""),
         ],
         projects=[
             PytestHtml(),
         ],
-        num_runs=3,
+        num_runs=5,
     )
 
-    run_experiments(
-        py_versions=[
-            PyPy(3, 9),
-        ],
-        cov_versions=[
-            ("none", None, None),
-            ("6.4", "coverage==6.4", ""),
-            (
-                "PR 1381",
-                "git+https://github.com/cfbolz/coveragepy.git@f_trace_lines",
-                "",
-            ),
-        ],
-        projects=[
-            PytestHtml(),
-        ],
-        num_runs=3,
-    )
+    # run_experiments(
+    #     py_versions=[
+    #         PyPy(3, 9),
+    #     ],
+    #     cov_versions=[
+    #         ("none", None, None),
+    #         ("6.4", "coverage==6.4", ""),
+    #         (
+    #             "PR 1381",
+    #             "git+https://github.com/cfbolz/coveragepy.git@f_trace_lines",
+    #             "",
+    #         ),
+    #     ],
+    #     projects=[
+    #         PytestHtml(),
+    #     ],
+    #     num_runs=3,
+    # )