- Add binary size analysis tool from Chromium.

runtime/third_party/binary_size/src/run_binary_size_analysis.py

Index: runtime/third_party/binary_size/src/run_binary_size_analysis.py
diff --git a/runtime/third_party/binary_size/src/run_binary_size_analysis.py b/runtime/third_party/binary_size/src/run_binary_size_analysis.py
new file mode 100755
index 0000000000000000000000000000000000000000..d97858d45399bca61438c7930dadf164b2af706a
--- /dev/null
+++ b/runtime/third_party/binary_size/src/run_binary_size_analysis.py
@@ -0,0 +1,666 @@
+#!/usr/bin/env python
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Generate a spatial analysis against an arbitrary library.
+
+To use, build the 'binary_size_tool' target. Then run this tool, passing
+in the location of the library to be analyzed along with any other options
+you desire.
+"""
+
+import collections
+import json
+import logging
+import multiprocessing
+import optparse
+import os
+import re
+import shutil
+import struct
+import subprocess
+import sys
+import tempfile
+import time
+
+import binary_size_utils
+import elf_symbolizer
+
+# Node dictionary keys. These are output in json read by the webapp so
+# keep them short to save file size.
+# Note: If these change, the webapp must also change.
+NODE_TYPE_KEY = 'k'
+NODE_NAME_KEY = 'n'
+NODE_CHILDREN_KEY = 'children'
+NODE_SYMBOL_TYPE_KEY = 't'
+NODE_SYMBOL_SIZE_KEY = 'value'
+NODE_MAX_DEPTH_KEY = 'maxDepth'
+NODE_LAST_PATH_ELEMENT_KEY = 'lastPathElement'
+
+# The display name of the bucket where we put symbols without path.
+NAME_NO_PATH_BUCKET = '(No Path)'
+
+# Try to keep data buckets smaller than this to avoid killing the
+# graphing lib.
+BIG_BUCKET_LIMIT = 3000
+
+
+def _MkChild(node, name):
+  child = node[NODE_CHILDREN_KEY].get(name)
+  if child is None:
+    child = {NODE_NAME_KEY: name,
+             NODE_CHILDREN_KEY: {}}
+    node[NODE_CHILDREN_KEY][name] = child
+  return child
+
+
+
+def SplitNoPathBucket(node):
+  """NAME_NO_PATH_BUCKET can be too large for the graphing lib to
+  handle. Split it into sub-buckets in that case."""
+  root_children = node[NODE_CHILDREN_KEY]
+  if NAME_NO_PATH_BUCKET in root_children:
+    no_path_bucket = root_children[NAME_NO_PATH_BUCKET]
+    old_children = no_path_bucket[NODE_CHILDREN_KEY]
+    count = 0
+    for symbol_type, symbol_bucket in old_children.iteritems():
+      count += len(symbol_bucket[NODE_CHILDREN_KEY])
+    if count > BIG_BUCKET_LIMIT:
+      new_children = {}
+      no_path_bucket[NODE_CHILDREN_KEY] = new_children
+      current_bucket = None
+      index = 0
+      for symbol_type, symbol_bucket in old_children.iteritems():
+        for symbol_name, value in symbol_bucket[NODE_CHILDREN_KEY].iteritems():
+          if index % BIG_BUCKET_LIMIT == 0:
+            group_no = (index / BIG_BUCKET_LIMIT) + 1
+            current_bucket = _MkChild(no_path_bucket,
+                                      '%s subgroup %d' % (NAME_NO_PATH_BUCKET,
+                                                          group_no))
+            assert not NODE_TYPE_KEY in node or node[NODE_TYPE_KEY] == 'p'
+            node[NODE_TYPE_KEY] = 'p'  # p for path
+          index += 1
+          symbol_size = value[NODE_SYMBOL_SIZE_KEY]
+          AddSymbolIntoFileNode(current_bucket, symbol_type,
+                                symbol_name, symbol_size)
+
+
+def MakeChildrenDictsIntoLists(node):
+  largest_list_len = 0
+  if NODE_CHILDREN_KEY in node:
+    largest_list_len = len(node[NODE_CHILDREN_KEY])
+    child_list = []
+    for child in node[NODE_CHILDREN_KEY].itervalues():
+      child_largest_list_len = MakeChildrenDictsIntoLists(child)
+      if child_largest_list_len > largest_list_len:
+        largest_list_len = child_largest_list_len
+      child_list.append(child)
+    node[NODE_CHILDREN_KEY] = child_list
+
+  return largest_list_len
+
+
+def AddSymbolIntoFileNode(node, symbol_type, symbol_name, symbol_size):
+  """Puts symbol into the file path node |node|.
+  Returns the number of added levels in tree. I.e. returns 2."""
+
+  # 'node' is the file node and first step is to find its symbol-type bucket.
+  node[NODE_LAST_PATH_ELEMENT_KEY] = True
+  node = _MkChild(node, symbol_type)
+  assert not NODE_TYPE_KEY in node or node[NODE_TYPE_KEY] == 'b'
+  node[NODE_SYMBOL_TYPE_KEY] = symbol_type
+  node[NODE_TYPE_KEY] = 'b'  # b for bucket
+
+  # 'node' is now the symbol-type bucket. Make the child entry.
+  node = _MkChild(node, symbol_name)
+  if NODE_CHILDREN_KEY in node:
+    if node[NODE_CHILDREN_KEY]:
+      logging.warning('A container node used as symbol for %s.' % symbol_name)
+    # This is going to be used as a leaf so no use for child list.
+    del node[NODE_CHILDREN_KEY]
+  node[NODE_SYMBOL_SIZE_KEY] = symbol_size
+  node[NODE_SYMBOL_TYPE_KEY] = symbol_type
+  node[NODE_TYPE_KEY] = 's'  # s for symbol
+
+  return 2  # Depth of the added subtree.
+
+
+def MakeCompactTree(symbols, symbol_path_origin_dir):
+  result = {NODE_NAME_KEY: '/',
+            NODE_CHILDREN_KEY: {},
+            NODE_TYPE_KEY: 'p',
+            NODE_MAX_DEPTH_KEY: 0}
+  seen_symbol_with_path = False
+  cwd = os.path.abspath(os.getcwd())
+  for symbol_name, symbol_type, symbol_size, file_path, _address in symbols:
+
+    if 'vtable for ' in symbol_name:
+      symbol_type = '@'  # hack to categorize these separately
+    # Take path like '/foo/bar/baz', convert to ['foo', 'bar', 'baz']
+    if file_path and file_path != "??":
+      file_path = os.path.abspath(os.path.join(symbol_path_origin_dir,
+                                               file_path))
+      # Let the output structure be relative to $CWD if inside $CWD,
+      # otherwise relative to the disk root. This is to avoid
+      # unnecessary click-through levels in the output.
+      if file_path.startswith(cwd + os.sep):
+        file_path = file_path[len(cwd):]
+      if file_path.startswith('/'):
+        file_path = file_path[1:]
+      seen_symbol_with_path = True
+    else:
+      file_path = NAME_NO_PATH_BUCKET
+
+    path_parts = file_path.split('/')
+
+    # Find pre-existing node in tree, or update if it already exists
+    node = result
+    depth = 0
+    while len(path_parts) > 0:
+      path_part = path_parts.pop(0)
+      if len(path_part) == 0:
+        continue
+      depth += 1
+      node = _MkChild(node, path_part)
+      assert not NODE_TYPE_KEY in node or node[NODE_TYPE_KEY] == 'p'
+      node[NODE_TYPE_KEY] = 'p'  # p for path
+
+    depth += AddSymbolIntoFileNode(node, symbol_type, symbol_name, symbol_size)
+    result[NODE_MAX_DEPTH_KEY] = max(result[NODE_MAX_DEPTH_KEY], depth)
+
+  if not seen_symbol_with_path:
+    logging.warning('Symbols lack paths. Data will not be structured.')
+
+  # The (no path) bucket can be extremely large if we failed to get
+  # path information. Split it into subgroups if needed.
+  SplitNoPathBucket(result)
+
+  largest_list_len = MakeChildrenDictsIntoLists(result)
+
+  if largest_list_len > BIG_BUCKET_LIMIT:
+    logging.warning('There are sections with %d nodes. '
+                    'Results might be unusable.' % largest_list_len)
+  return result
+
+
+def DumpCompactTree(symbols, symbol_path_origin_dir, outfile):
+  tree_root = MakeCompactTree(symbols, symbol_path_origin_dir)
+  with open(outfile, 'w') as out:
+    out.write('var tree_data=')
+    # Use separators without whitespace to get a smaller file.
+    json.dump(tree_root, out, separators=(',', ':'))
+  print('Writing %d bytes json' % os.path.getsize(outfile))
+
+
+def MakeSourceMap(symbols):
+  sources = {}
+  for _sym, _symbol_type, size, path, _address in symbols:
+    key = None
+    if path:
+      key = os.path.normpath(path)
+    else:
+      key = '[no path]'
+    if key not in sources:
+      sources[key] = {'path': path, 'symbol_count': 0, 'size': 0}
+    record = sources[key]
+    record['size'] += size
+    record['symbol_count'] += 1
+  return sources
+
+
+# Regex for parsing "nm" output. A sample line looks like this:
+# 0167b39c 00000018 t ACCESS_DESCRIPTION_free /path/file.c:95
+#
+# The fields are: address, size, type, name, source location
+# Regular expression explained ( see also: https://xkcd.com/208 ):
+# ([0-9a-f]{8,}+)   The address
+# [\s]+             Whitespace separator
+# ([0-9a-f]{8,}+)   The size. From here on out it's all optional.
+# [\s]+             Whitespace separator
+# (\S?)             The symbol type, which is any non-whitespace char
+# [\s*]             Whitespace separator
+# ([^\t]*)          Symbol name, any non-tab character (spaces ok!)
+# [\t]?             Tab separator
+# (.*)              The location (filename[:linennum|?][ (discriminator n)]
+sNmPattern = re.compile(
+  r'([0-9a-f]{8,})[\s]+([0-9a-f]{8,})[\s]*(\S?)[\s*]([^\t]*)[\t]?(.*)')
+
+class Progress():
+  def __init__(self):
+    self.count = 0
+    self.skip_count = 0
+    self.collisions = 0
+    self.time_last_output = time.time()
+    self.count_last_output = 0
+    self.disambiguations = 0
+    self.was_ambiguous = 0
+
+
+def RunElfSymbolizer(outfile, library, addr2line_binary, nm_binary, jobs,
+                     disambiguate, src_path):
+  nm_output = RunNm(library, nm_binary)
+  nm_output_lines = nm_output.splitlines()
+  nm_output_lines_len = len(nm_output_lines)
+  address_symbol = {}
+  progress = Progress()
+  def map_address_symbol(symbol, addr):
+    progress.count += 1
+    if addr in address_symbol:
+      # 'Collision between %s and %s.' % (str(symbol.name),
+      #                                   str(address_symbol[addr].name))
+      progress.collisions += 1
+    else:
+      if symbol.disambiguated:
+        progress.disambiguations += 1
+      if symbol.was_ambiguous:
+        progress.was_ambiguous += 1
+
+      address_symbol[addr] = symbol
+
+    progress_output()
+
+  def progress_output():
+    progress_chunk = 100
+    if progress.count % progress_chunk == 0:
+      time_now = time.time()
+      time_spent = time_now - progress.time_last_output
+      if time_spent > 1.0:
+        # Only output at most once per second.
+        progress.time_last_output = time_now
+        chunk_size = progress.count - progress.count_last_output
+        progress.count_last_output = progress.count
+        if time_spent > 0:
+          speed = chunk_size / time_spent
+        else:
+          speed = 0
+        progress_percent = (100.0 * (progress.count + progress.skip_count) /
+                            nm_output_lines_len)
+        disambiguation_percent = 0
+        if progress.disambiguations != 0:
+          disambiguation_percent = (100.0 * progress.disambiguations /
+                                    progress.was_ambiguous)
+
+        sys.stdout.write('\r%.1f%%: Looked up %d symbols (%d collisions, '
+              '%d disambiguations where %.1f%% succeeded)'
+              ' - %.1f lookups/s.' %
+              (progress_percent, progress.count, progress.collisions,
+               progress.disambiguations, disambiguation_percent, speed))
+
+  # In case disambiguation was disabled, we remove the source path (which upon
+  # being set signals the symbolizer to enable disambiguation)
+  if not disambiguate:
+    src_path = None
+  symbolizer = elf_symbolizer.ELFSymbolizer(library, addr2line_binary,
+                                            map_address_symbol,
+                                            max_concurrent_jobs=jobs,
+                                            source_root_path=src_path)
+  user_interrupted = False
+  try:
+    for line in nm_output_lines:
+      match = sNmPattern.match(line)
+      if match:
+        location = match.group(5)
+        if not location:
+          addr = int(match.group(1), 16)
+          size = int(match.group(2), 16)
+          if addr in address_symbol:  # Already looked up, shortcut
+                                      # ELFSymbolizer.
+            map_address_symbol(address_symbol[addr], addr)
+            continue
+          elif size == 0:
+            # Save time by not looking up empty symbols (do they even exist?)
+            print('Empty symbol: ' + line)
+          else:
+            symbolizer.SymbolizeAsync(addr, addr)
+            continue
+
+      progress.skip_count += 1
+  except KeyboardInterrupt:
+    user_interrupted = True
+    print('Interrupting - killing subprocesses. Please wait.')
+
+  try:
+    symbolizer.Join()
+  except KeyboardInterrupt:
+    # Don't want to abort here since we will be finished in a few seconds.
+    user_interrupted = True
+    print('Patience you must have my young padawan.')
+
+  print ''
+
+  if user_interrupted:
+    print('Skipping the rest of the file mapping. '
+          'Output will not be fully classified.')
+
+  symbol_path_origin_dir = os.path.dirname(os.path.abspath(library))
+
+  with open(outfile, 'w') as out:
+    for line in nm_output_lines:
+      match = sNmPattern.match(line)
+      if match:
+        location = match.group(5)
+        if not location:
+          addr = int(match.group(1), 16)
+          symbol = address_symbol.get(addr)
+          if symbol is not None:
+            path = '??'
+            if symbol.source_path is not None:
+              path = os.path.abspath(os.path.join(symbol_path_origin_dir,
+                                                  symbol.source_path))
+            line_number = 0
+            if symbol.source_line is not None:
+              line_number = symbol.source_line
+            out.write('%s\t%s:%d\n' % (line, path, line_number))
+            continue
+
+      out.write('%s\n' % line)
+
+  print('%d symbols in the results.' % len(address_symbol))
+
+
+def RunNm(binary, nm_binary):
+  cmd = [nm_binary, '-C', '--print-size', '--size-sort', '--reverse-sort',
+         binary]
+  nm_process = subprocess.Popen(cmd,
+                                stdout=subprocess.PIPE,
+                                stderr=subprocess.PIPE)
+  (process_output, err_output) = nm_process.communicate()
+
+  if nm_process.returncode != 0:
+    if err_output:
+      raise Exception, err_output
+    else:
+      raise Exception, process_output
+
+  return process_output
+
+
+def GetNmSymbols(nm_infile, outfile, library, jobs, verbose,
+                 addr2line_binary, nm_binary, disambiguate, src_path):
+  if nm_infile is None:
+    if outfile is None:
+      outfile = tempfile.NamedTemporaryFile(delete=False).name
+
+    if verbose:
+      print 'Running parallel addr2line, dumping symbols to ' + outfile
+    RunElfSymbolizer(outfile, library, addr2line_binary, nm_binary, jobs,
+                     disambiguate, src_path)
+
+    nm_infile = outfile
+
+  elif verbose:
+    print 'Using nm input from ' + nm_infile
+  with file(nm_infile, 'r') as infile:
+    return list(binary_size_utils.ParseNm(infile))
+
+
+PAK_RESOURCE_ID_TO_STRING = { "inited": False }
+
+def LoadPakIdsFromResourceFile(filename):
+  """Given a file name, it loads everything that looks like a resource id
+  into PAK_RESOURCE_ID_TO_STRING."""
+  with open(filename) as resource_header:
+    for line in resource_header:
+      if line.startswith("#define "):
+        line_data = line.split()
+        if len(line_data) == 3:
+          try:
+            resource_number = int(line_data[2])
+            resource_name = line_data[1]
+            PAK_RESOURCE_ID_TO_STRING[resource_number] = resource_name
+          except ValueError:
+            pass
+
+def GetReadablePakResourceName(pak_file, resource_id):
+  """Pak resources have a numeric identifier. It is not helpful when
+  trying to locate where footprint is generated. This does its best to
+  map the number to a usable string."""
+  if not PAK_RESOURCE_ID_TO_STRING['inited']:
+    # Try to find resource header files generated by grit when
+    # building the pak file. We'll look for files named *resources.h"
+    # and lines of the type:
+    #    #define MY_RESOURCE_JS 1234
+    PAK_RESOURCE_ID_TO_STRING['inited'] = True
+    gen_dir = os.path.join(os.path.dirname(pak_file), 'gen')
+    if os.path.isdir(gen_dir):
+      for dirname, _dirs, files in os.walk(gen_dir):
+        for filename in files:
+          if filename.endswith('resources.h'):
+            LoadPakIdsFromResourceFile(os.path.join(dirname, filename))
+  return PAK_RESOURCE_ID_TO_STRING.get(resource_id,
+                                       'Pak Resource %d' % resource_id)
+
+def AddPakData(symbols, pak_file):
+  """Adds pseudo-symbols from a pak file."""
+  pak_file = os.path.abspath(pak_file)
+  with open(pak_file, 'rb') as pak:
+    data = pak.read()
+
+  PAK_FILE_VERSION = 4
+  HEADER_LENGTH = 2 * 4 + 1  # Two uint32s. (file version, number of entries)
+                             # and one uint8 (encoding of text resources)
+  INDEX_ENTRY_SIZE = 2 + 4  # Each entry is a uint16 and a uint32.
+  version, num_entries, _encoding = struct.unpack('<IIB', data[:HEADER_LENGTH])
+  assert version == PAK_FILE_VERSION, ('Unsupported pak file '
+                                       'version (%d) in %s. Only '
+                                       'support version %d' %
+                                       (version, pak_file, PAK_FILE_VERSION))
+  if num_entries > 0:
+    # Read the index and data.
+    data = data[HEADER_LENGTH:]
+    for _ in range(num_entries):
+      resource_id, offset = struct.unpack('<HI', data[:INDEX_ENTRY_SIZE])
+      data = data[INDEX_ENTRY_SIZE:]
+      _next_id, next_offset = struct.unpack('<HI', data[:INDEX_ENTRY_SIZE])
+      resource_size = next_offset - offset
+
+      symbol_name = GetReadablePakResourceName(pak_file, resource_id)
+      symbol_path = pak_file
+      symbol_type = 'd' # Data. Approximation.
+      symbol_size = resource_size
+      symbols.append((symbol_name, symbol_type, symbol_size, symbol_path))
+
+def _find_in_system_path(binary):
+  """Locate the full path to binary in the system path or return None
+  if not found."""
+  system_path = os.environ["PATH"].split(os.pathsep)
+  for path in system_path:
+    binary_path = os.path.join(path, binary)
+    if os.path.isfile(binary_path):
+      return binary_path
+  return None
+
+def CheckDebugFormatSupport(library, addr2line_binary):
+  """Kills the program if debug data is in an unsupported format.
+
+  There are two common versions of the DWARF debug formats and
+  since we are right now transitioning from DWARF2 to newer formats,
+  it's possible to have a mix of tools that are not compatible. Detect
+  that and abort rather than produce meaningless output."""
+  tool_output = subprocess.check_output([addr2line_binary, '--version'])
+  version_re = re.compile(r'^GNU [^ ]+ .* (\d+).(\d+).*?$', re.M)
+  parsed_output = version_re.match(tool_output)
+  major = int(parsed_output.group(1))
+  minor = int(parsed_output.group(2))
+  supports_dwarf4 = major > 2 or major == 2 and minor > 22
+
+  if supports_dwarf4:
+    return
+
+  print('Checking version of debug information in %s.' % library)
+  debug_info = subprocess.check_output(['readelf', '--debug-dump=info',
+                                       '--dwarf-depth=1', library])
+  dwarf_version_re = re.compile(r'^\s+Version:\s+(\d+)$', re.M)
+  parsed_dwarf_format_output = dwarf_version_re.search(debug_info)
+  version = int(parsed_dwarf_format_output.group(1))
+  if version > 2:
+    print('The supplied tools only support DWARF2 debug data but the binary\n' +
+          'uses DWARF%d. Update the tools or compile the binary\n' % version +
+          'with -gdwarf-2.')
+    sys.exit(1)
+
+
+def main():
+  usage = """%prog [options]
+
+  Runs a spatial analysis on a given library, looking up the source locations
+  of its symbols and calculating how much space each directory, source file,
+  and so on is taking. The result is a report that can be used to pinpoint
+  sources of large portions of the binary, etceteras.
+
+  Under normal circumstances, you only need to pass two arguments, thusly:
+
+      %prog --library /path/to/library --destdir /path/to/output
+
+  In this mode, the program will dump the symbols from the specified library
+  and map those symbols back to source locations, producing a web-based
+  report in the specified output directory.
+
+  Other options are available via '--help'.
+  """
+  parser = optparse.OptionParser(usage=usage)
+  parser.add_option('--nm-in', metavar='PATH',
+                    help='if specified, use nm input from <path> instead of '
+                    'generating it. Note that source locations should be '
+                    'present in the file; i.e., no addr2line symbol lookups '
+                    'will be performed when this option is specified. '
+                    'Mutually exclusive with --library.')
+  parser.add_option('--destdir', metavar='PATH',
+                    help='write output to the specified directory. An HTML '
+                    'report is generated here along with supporting files; '
+                    'any existing report will be overwritten.')
+  parser.add_option('--library', metavar='PATH',
+                    help='if specified, process symbols in the library at '
+                    'the specified path. Mutually exclusive with --nm-in.')
+  parser.add_option('--pak', metavar='PATH',
+                    help='if specified, includes the contents of the '
+                    'specified *.pak file in the output.')
+  parser.add_option('--nm-binary',
+                    help='use the specified nm binary to analyze library. '
+                    'This is to be used when the nm in the path is not for '
+                    'the right architecture or of the right version.')
+  parser.add_option('--addr2line-binary',
+                    help='use the specified addr2line binary to analyze '
+                    'library. This is to be used when the addr2line in '
+                    'the path is not for the right architecture or '
+                    'of the right version.')
+  parser.add_option('--jobs', type='int',
+                    help='number of jobs to use for the parallel '
+                    'addr2line processing pool; defaults to 1. More '
+                    'jobs greatly improve throughput but eat RAM like '
+                    'popcorn, and take several gigabytes each. Start low '
+                    'and ramp this number up until your machine begins to '
+                    'struggle with RAM. '
+                    'This argument is only valid when using --library.')
+  parser.add_option('-v', '--verbose', dest='verbose', action='store_true',
+                    help='be verbose, printing lots of status information.')
+  parser.add_option('--nm-out', metavar='PATH',
+                    help='(deprecated) No-op. nm.out is stored in --destdir.')
+  parser.add_option('--no-nm-out', action='store_true',
+                    help='do not keep the nm output file. This file is useful '
+                    'if you want to see the fully processed nm output after '
+                    'the symbols have been mapped to source locations, or if '
+                    'you plan to run explain_binary_size_delta.py. By default '
+                    'the file \'nm.out\' is placed alongside the generated '
+                    'report. The nm.out file is only created when using '
+                    '--library.')
+  parser.add_option('--disable-disambiguation', action='store_true',
+                    help='disables the disambiguation process altogether,'
+                    ' NOTE: this may, depending on your toolchain, produce'
+                    ' output with some symbols at the top layer if addr2line'
+                    ' could not get the entire source path.')
+  parser.add_option('--source-path', default='./',
+                    help='the path to the source code of the output binary, '
+                    'default set to current directory. Used in the'
+                    ' disambiguation process.')
+  opts, _args = parser.parse_args()
+
+  if ((not opts.library) and (not opts.nm_in)) or (opts.library and opts.nm_in):
+    parser.error('exactly one of --library or --nm-in is required')
+  if opts.nm_out:
+    print >> sys.stderr, ('WARNING: --nm-out is deprecated and has no effect.')
+  if (opts.nm_in):
+    if opts.jobs:
+      print >> sys.stderr, ('WARNING: --jobs has no effect '
+                            'when used with --nm-in')
+  if not opts.destdir:
+    parser.error('--destdir is a required argument')
+  if not opts.jobs:
+    # Use the number of processors but cap between 2 and 4 since raw
+    # CPU power isn't the limiting factor. It's I/O limited, memory
+    # bus limited and available-memory-limited. Too many processes and
+    # the computer will run out of memory and it will be slow.
+    opts.jobs = max(2, min(4, str(multiprocessing.cpu_count())))
+
+  if opts.addr2line_binary:
+    assert os.path.isfile(opts.addr2line_binary)
+    addr2line_binary = opts.addr2line_binary
+  else:
+    addr2line_binary = _find_in_system_path('addr2line')
+    assert addr2line_binary, 'Unable to find addr2line in the path. '\
+        'Use --addr2line-binary to specify location.'
+
+  if opts.nm_binary:
+    assert os.path.isfile(opts.nm_binary)
+    nm_binary = opts.nm_binary
+  else:
+    nm_binary = _find_in_system_path('nm')
+    assert nm_binary, 'Unable to find nm in the path. Use --nm-binary '\
+        'to specify location.'
+
+  if opts.pak:
+    assert os.path.isfile(opts.pak), 'Could not find ' % opts.pak
+
+  print('addr2line: %s' % addr2line_binary)
+  print('nm: %s' % nm_binary)
+
+  if opts.library:
+    CheckDebugFormatSupport(opts.library, addr2line_binary)
+
+  # Prepare output directory and report guts
+  if not os.path.exists(opts.destdir):
+    os.makedirs(opts.destdir, 0755)
+  nm_out = os.path.join(opts.destdir, 'nm.out')
+  if opts.no_nm_out:
+    nm_out = None
+
+  # Copy report boilerplate into output directory. This also proves that the
+  # output directory is safe for writing, so there should be no problems writing
+  # the nm.out file later.
+  data_js_file_name = os.path.join(opts.destdir, 'data.js')
+  d3_out = os.path.join(opts.destdir, 'd3')
+  if not os.path.exists(d3_out):
+    os.makedirs(d3_out, 0755)
+  d3_src = os.path.join(os.path.dirname(__file__),
+                        '..',
+                        '..',
+                        'd3', 'src')
+  template_src = os.path.join(os.path.dirname(__file__),
+                              'template')
+  shutil.copy(os.path.join(d3_src, 'LICENSE'), d3_out)
+  shutil.copy(os.path.join(d3_src, 'd3.js'), d3_out)
+  shutil.copy(os.path.join(template_src, 'index.html'), opts.destdir)
+  shutil.copy(os.path.join(template_src, 'D3SymbolTreeMap.js'), opts.destdir)
+
+  # Run nm and/or addr2line to gather the data
+  symbols = GetNmSymbols(opts.nm_in, nm_out, opts.library,
+                         opts.jobs, opts.verbose is True,
+                         addr2line_binary, nm_binary,
+                         opts.disable_disambiguation is None,
+                         opts.source_path)
+
+  # Post-processing
+  if opts.pak:
+    AddPakData(symbols, opts.pak)
+  if opts.library:
+    symbol_path_origin_dir = os.path.dirname(os.path.abspath(opts.library))
+  else:
+    # Just a guess. Hopefully all paths in the input file are absolute.
+    symbol_path_origin_dir = os.path.abspath(os.getcwd())
+  # Dump JSON for the HTML report.
+  DumpCompactTree(symbols, symbol_path_origin_dir, data_js_file_name)
+  print 'Report saved to ' + opts.destdir + '/index.html'
+
+if __name__ == '__main__':
+  sys.exit(main())