Add heap log processing script originally written by Kevin.

tools/process-heap-prof.py

Index: tools/process-heap-prof.py
diff --git a/tools/process-heap-prof.py b/tools/process-heap-prof.py
new file mode 100755
index 0000000000000000000000000000000000000000..79c49f83d8ca300d2aa3f2f16ac5ff7cc0b05e2b
--- /dev/null
+++ b/tools/process-heap-prof.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# Copyright 2009 the V8 project authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#     * Neither the name of Google Inc. nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# This is an utility for converting V8 heap logs into .hp files that can
+# be further processed using 'hp2ps' tool (bundled with GHC and Valgrind)
+# to produce heap usage histograms.
+
+# Sample usage:
+# $ ./shell --log-gc script.js
+# $ tools/process-heap-prof.py v8.log | hp2ps -c > script-heap-graph.ps
+# ('-c' enables color, see hp2ps manual page for more options)
+
+import csv, sys, time
+
+def process_logfile(filename):
+  sample_time = 0.0
+  sampling = False
+  try:
+    logfile = open(filename, 'rb')
+    try:
+      logreader = csv.reader(logfile)
+
+      print('JOB "v8"')
+      print('DATE "%s"' % time.asctime(time.localtime()))
+      print('SAMPLE_UNIT "seconds"')
+      print('VALUE_UNIT "bytes"')
+
+      for row in logreader:
+        if row[0] == 'heap-sample-begin' and row[1] == 'Heap':
+          sample_time = float(row[3]) + float(row[4])/1000000.0
+          print('BEGIN_SAMPLE %.2f' % sample_time)
+          sampling = True
+        elif row[0] == 'heap-sample-end' and row[1] == 'Heap':
+          print('END_SAMPLE %.2f' % sample_time)
+          sampling = False
+        elif row[0] == 'heap-sample-item' and sampling:
+          print('%s %d' % (row[1], int(row[3])))
+    finally:
+      logfile.close()
+  except:
+    sys.exit('can\'t open %s' % filename)
+
+process_logfile(sys.argv[1])