1 files changed, 64 insertions, 0 deletions
diff --git a/build/util/count_ctors.py b/build/util/count_ctors.py
new file mode 100644
index 0000000000..6a3a870685
--- /dev/null
+++ b/build/util/count_ctors.py
@@ -0,0 +1,64 @@
+
+#!/usr/bin/python
+import json
+import re
+import subprocess
+import sys
+
+def count_ctors(filename):
+    proc = subprocess.Popen(
+        ['readelf', '-W', '-S', filename], stdout=subprocess.PIPE)
+
+    # Some versions of ld produce both .init_array and .ctors.  So we have
+    # to check for both.
+    n_init_array_ctors = 0
+    have_init_array = False
+    n_ctors_ctors = 0
+    have_ctors = False
+
+    for line in proc.stdout:
+        f = line.split()
+        if len(f) != 11:
+            continue
+        # Don't try to int()-parse the header line for the section summaries.
+        if not re.match("\\[\\d+\\]", f[0]):
+            continue
+        section_name, contents, size, align = f[1], f[2], int(f[5], 16), int(f[10])
+        if section_name == ".ctors" and contents == "PROGBITS":
+            have_ctors = True
+            # Subtract 2 for the uintptr_t(-1) header and the null terminator.
+            n_ctors_ctors = size / align - 2
+        if section_name == ".init_array" and contents == "INIT_ARRAY":
+            have_init_array = True
+            n_init_array_ctors = size / align
+
+    if have_init_array:
+        # Even if we have .ctors, we shouldn't have any constructors in .ctors.
+        # Complain if .ctors does not look how we expect it to.
+        if have_ctors and n_ctors_ctors != 0:
+            print >>sys.stderr, "Unexpected .ctors contents for", filename
+            sys.exit(1)
+        return n_init_array_ctors
+    if have_ctors:
+        return n_ctors_ctors
+
+    # We didn't find anything; somebody switched initialization mechanisms on
+    # us, or the binary is completely busted.  Complain either way.
+    print >>sys.stderr, "Couldn't find .init_array or .ctors in", filename
+    sys.exit(1)
+
+if __name__ == '__main__':
+    for f in sys.argv[1:]:
+        perfherder_data = {
+            "framework": {"name": "build_metrics"},
+            "suites": [{
+                "name": "compiler_metrics",
+                "subtests": [{
+                    "name": "num_constructors",
+                    "value": count_ctors(f),
+                    "alertThreshold": 0.25
+                }]}
+            ]
+        }
+        print "PERFHERDER_DATA: %s" % json.dumps(perfherder_data)
+