Index: tools/test_time.py
===================================================================
--- tools/test_time.py	(revision a1fbad03570c1d89928bcf9962192664b479ae9b)
+++ tools/test_time.py	(revision a1fbad03570c1d89928bcf9962192664b479ae9b)
@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+"""Inspect test results for timing information.
+
+Run on a file that contains results from tests/test.py to see results.
+"""
+
+
+import argparse
+from datetime import timedelta
+import re
+import statistics
+
+
+def parse_args(args=None):
+    parser = argparse.ArgumentParser(
+        description='Summarize performance results from a test run.')
+    parser.add_argument('result_file', type=argparse.FileType('r'))
+    return parser.parse_args(args)
+
+
+def str_to_time(time_str):
+    match = re.search('([0-9]+):([0-9]+)[.]([0-9]+)', time_str)
+    if not match:
+        raise Exception('Badly formatted')
+    minutes, seconds, milli = (int(x) for x in match.groups())
+    return timedelta(minutes=minutes, seconds=seconds, milliseconds=milli)
+
+
+def line_to_entry(line):
+    match = re.search('([^\t ]+) +PASSED +C( n/a|.*) - R( n/a|.*)', line)
+    if not match:
+        return None
+    test_id, compile_str, run_str = match.groups()
+    compile_time = None if ' n/a' == compile_str else str_to_time(compile_str)
+    run_time = None if ' n/a' == run_str else str_to_time(run_str)
+    return test_id, compile_time, run_time
+
+
+def iter_file_entries(open_file):
+    with open_file as file:
+        for line in file.readlines():
+            entry = line_to_entry(line)
+            if entry is not None:
+                yield entry
+
+
+def entry_to_compile_seconds(entry):
+    _id, compile_time, _run_time = entry
+    return compile_time.total_seconds()
+
+
+if '__main__' == __name__:
+    args = parse_args()
+    mean = statistics.geometric_mean(
+        map(entry_to_compile_seconds, iter_file_entries(args.result_file)))
+    print('Source File:', args.result_file.name)
+    print('Geometric Mean:', mean)