Reland of V2 of //tools/binary_size rewrite (diffs).

tools/binary_size/analyze.py

Index: tools/binary_size/analyze.py
diff --git a/tools/binary_size/analyze.py b/tools/binary_size/analyze.py
deleted file mode 100755
index 8a4eefc44df4e2107bc8c2a60c72cbe92e1b4c77..0000000000000000000000000000000000000000
--- a/tools/binary_size/analyze.py
+++ /dev/null
@@ -1,356 +0,0 @@
-#!/usr/bin/env python
-# Copyright 2017 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.
-
-"""Main Python API for analyzing binary size."""
-
-import argparse
-import ast
-import distutils.spawn
-import gzip
-import logging
-import os
-import re
-import subprocess
-
-import function_signature
-import helpers
-import mapfileparser
-import symbols
-
-
-# File format version for .size files.
-_SERIALIZATION_VERSION = 1
-
-
-def _OpenMaybeGz(path, mode=None):
-  """Calls `gzip.open()` if |path| ends in ".gz", otherwise calls `open()`."""
-  if path.endswith('.gz'):
-    if mode and 'w' in mode:
-      return gzip.GzipFile(path, mode, 1)
-    return gzip.open(path, mode)
-  return open(path, mode or 'r')
-
-
-def _EndsWithMaybeGz(path, suffix):
-  return path.endswith(suffix) or path.endswith(suffix + '.gz')
-
-
-def _IterLines(s):
-  prev_idx = -1
-  while True:
-    idx = s.find('\n', prev_idx + 1)
-    if idx == -1:
-      return
-    yield s[prev_idx + 1:idx]
-    prev_idx = idx
-
-
-def _UnmangleRemainingSymbols(symbol_group, tool_prefix):
-  """Uses c++filt to unmangle any symbols that need it."""
-  to_process = [s for s in symbol_group if s.name and s.name.startswith('_Z')]
-  if not to_process:
-    return
-
-  logging.info('Unmangling %d names', len(to_process))
-  proc = subprocess.Popen([tool_prefix + 'c++filt'], stdin=subprocess.PIPE,
-                          stdout=subprocess.PIPE)
-  stdout = proc.communicate('\n'.join(s.name for s in to_process))[0]
-  assert proc.returncode == 0
-
-  for i, line in enumerate(_IterLines(stdout)):
-    to_process[i].name = line
-
-
-def _NormalizeNames(symbol_group):
-  """Ensures that all names are formatted in a useful way.
-
-  This includes:
-    - Assigning of |function_signature| (for functions).
-    - Stripping of return types in |function_signature| and |name|.
-    - Stripping parameters from |name|.
-    - Moving "vtable for" and the like to be suffixes rather than prefixes.
-  """
-  found_prefixes = set()
-  for symbol in symbol_group:
-    if not symbol.name or symbol.name.startswith('*'):
-      # See comment in _RemoveDuplicatesAndCalculatePadding() about when this
-      # can happen.
-      continue
-
-    # E.g.: vtable for FOO
-    idx = symbol.name.find(' for ', 0, 30)
-    if idx != -1:
-      found_prefixes.add(symbol.name[:idx + 4])
-      symbol.name = symbol.name[idx + 5:] + ' [' + symbol.name[:idx] + ']'
-
-    # E.g.: virtual thunk to FOO
-    idx = symbol.name.find(' to ', 0, 30)
-    if idx != -1:
-      found_prefixes.add(symbol.name[:idx + 3])
-      symbol.name = symbol.name[idx + 4:] + ' [' + symbol.name[:idx] + ']'
-
-    # Strip out return type, and identify where parameter list starts.
-    if symbol.section == 't':
-      symbol.function_signature, symbol.name = (
-          function_signature.Parse(symbol.name))
-
-    # Remove anonymous namespaces (they just harm clustering).
-    symbol.name = symbol.name.replace('(anonymous namespace)::', '')
-
-  logging.debug('Found name prefixes of: %r', found_prefixes)
-
-
-def _NormalizeObjectPaths(symbol_group):
-  """Ensures that all paths are formatted in a useful way."""
-  for symbol in symbol_group:
-    if symbol.path:
-      if symbol.path.startswith('obj/'):
-        # Convert obj/third_party/... -> third_party/...
-        symbol.path = symbol.path[4:]
-      elif symbol.path.startswith('../../'):
-        # Convert ../../third_party/... -> third_party/...
-        symbol.path = symbol.path[6:]
-      if symbol.path.endswith(')'):
-        # Convert foo/bar.a(baz.o) -> foo/bar.a/baz.o
-        start_idx = symbol.path.index('(')
-        paren_path = symbol.path[start_idx + 1:-1]
-        symbol.path = symbol.path[:start_idx] + os.path.sep + paren_path
-
-
-def _RemoveDuplicatesAndCalculatePadding(symbol_group):
-  """Removes symbols at the same address and calculates the |padding| field.
-
-  Symbols must already be sorted by |address|.
-  """
-  i = 0
-  to_remove = set()
-  all_symbols = symbol_group.symbols
-  for i in xrange(len(all_symbols)):
-    prev_symbol = all_symbols[i - 1]
-    symbol = all_symbols[i]
-    if prev_symbol.section_name is not symbol.section_name:
-      continue
-    if symbol.address > 0 and prev_symbol.address > 0:
-      # Fold symbols that are at the same address (happens in nm output).
-      if symbol.address == prev_symbol.address:
-        symbol.size = max(prev_symbol.size, symbol.size)
-        to_remove.add(i)
-        continue
-      # Even with symbols at the same address removed, overlaps can still
-      # happen. In this case, padding will be negative (and this is fine).
-      padding = symbol.address - prev_symbol.end_address
-      # These thresholds were found by manually auditing arm32 Chrome.
-      # E.g.: Set them to 0 and see what warnings get logged.
-      # TODO(agrieve): See if these thresholds make sense for architectures
-      #     other than arm32.
-      if (symbol.section in 'rd' and padding >= 256 or
-          symbol.section in 't' and padding >= 64):
-        # For nm data, this is caused by data that has no associated symbol.
-        # The linker map file lists them with no name, but with a file.
-        # Example:
-        #   .data 0x02d42764 0x120 .../V8SharedWorkerGlobalScope.o
-        # Where as most look like:
-        #   .data.MANGLED_NAME...
-        logging.debug('Large padding of %d between:\n  A) %r\n  B) %r' % (
-                      padding, prev_symbol, symbol))
-        continue
-      symbol.padding = padding
-      symbol.size += padding
-      assert symbol.size >= 0, 'Symbol has negative size: %r' % symbol
-  # Map files have no overlaps, so worth special-casing the no-op case.
-  if to_remove:
-    logging.info('Removing %d overlapping symbols', len(to_remove))
-    symbol_group.symbols = (
-        [s for i, s in enumerate(all_symbols) if i not in to_remove])
-
-
-def _PrintStats(result, write_func):
-  """Prints out how accurate |result| is."""
-  for section in symbols.SECTION_TO_SECTION_NAME:
-    if section == 'd':
-      expected_size = sum(v for k, v in result.section_sizes.iteritems()
-                          if k.startswith('.data'))
-    else:
-      expected_size = result.section_sizes[
-          symbols.SECTION_TO_SECTION_NAME[section]]
-
-    def one_stat(group):
-      template = ('Section %s has %.1f%% of %d bytes accounted for from '
-                  '%d symbols. %d bytes are unaccounted for. Padding '
-                  'accounts for %d bytes\n')
-      actual_size = group.size
-      count = len(group)
-      padding = group.padding
-      size_percent = 100.0 * actual_size / expected_size
-      return (template % (section, size_percent, actual_size, count,
-                          expected_size - actual_size, padding))
-
-    in_section = result.symbol_group.WhereInSection(section)
-    write_func(one_stat(in_section))
-
-    star_syms = in_section.WhereNameMatches(r'^\*')
-    attributed_syms = star_syms.Inverted().WhereHasAnyAttribution()
-    anonymous_syms = attributed_syms.Inverted()
-    if star_syms or anonymous_syms:
-      missing_size = star_syms.size + anonymous_syms.size
-      write_func(('+ Without %d merge sections and %d anonymous entries ('
-                  'accounting for %d bytes):\n') % (
-          len(star_syms),  len(anonymous_syms), missing_size))
-      write_func('+ ' + one_stat(attributed_syms))
-
-
-def _SaveResult(result, file_obj):
-  """Saves the result to the given file object."""
-  # Store one bucket per line.
-  file_obj.write('%d\n' % _SERIALIZATION_VERSION)
-  file_obj.write('%r\n' % result.section_sizes)
-  file_obj.write('%d\n' % len(result.symbol_group))
-  prev_section_name = None
-  # Store symbol fields as tab-separated.
-  # Store only non-derived fields.
-  for symbol in result.symbol_group:
-    if symbol.section_name != prev_section_name:
-      file_obj.write('%s\n' % symbol.section_name)
-      prev_section_name = symbol.section_name
-    # Don't write padding nor name since these are derived values.
-    file_obj.write('%x\t%x\t%s\t%s\n' % (
-        symbol.address, symbol.size_without_padding,
-        symbol.function_signature or symbol.name or '',
-        symbol.path or ''))
-
-
-def _LoadResults(file_obj):
-  """Loads a result from the given file."""
-  lines = iter(file_obj)
-  actual_version = int(next(lines))
-  assert actual_version == _SERIALIZATION_VERSION, (
-      'Version mismatch. Need to write some upgrade code.')
-
-  section_sizes = ast.literal_eval(next(lines))
-  num_syms = int(next(lines))
-  symbol_list = [None] * num_syms
-  section_name = None
-  for i in xrange(num_syms):
-    line = next(lines)[:-1]
-    if '\t' not in line:
-      section_name = intern(line)
-      line = next(lines)[:-1]
-    new_sym = symbols.Symbol.__new__(symbols.Symbol)
-    parts = line.split('\t')
-    new_sym.section_name = section_name
-    new_sym.address = int(parts[0], 16)
-    new_sym.size = int(parts[1], 16)
-    new_sym.name = parts[2] or None
-    new_sym.path = parts[3] or None
-    new_sym.padding = 0  # Derived
-    new_sym.function_signature = None  # Derived
-    symbol_list[i] = new_sym
-
-  # Recompute derived values (padding and function names).
-  result = mapfileparser.ParseResult(symbol_list, section_sizes)
-  logging.info('Calculating padding')
-  _RemoveDuplicatesAndCalculatePadding(result.symbol_group)
-  logging.info('Deriving signatures')
-  # Re-parse out function parameters.
-  _NormalizeNames(result.symbol_group.WhereInSection('t'))
-  return result
-
-
-def AddOptions(parser):
-  parser.add_argument('input_file',
-                      help='Path to input file. Can be a linker .map file, an '
-                           'unstripped binary, or a saved result from '
-                           'analyze.py')
-  parser.add_argument('--tool-prefix', default='',
-                      help='Path prefix for c++filt.')
-  parser.add_argument('--output-directory',
-                      help='Path to the root build directory.')
-
-
-def _DetectToolPrefix(tool_prefix, input_file, output_directory=None):
-  """Calls Analyze with values from args."""
-  if not output_directory:
-    abs_path = os.path.abspath(input_file)
-    release_idx = abs_path.find('Release')
-    if release_idx != -1:
-      output_directory = abs_path[:release_idx] + 'Release'
-      output_directory = os.path.relpath(abs_path[:release_idx] + '/Release')
-      logging.debug('Detected --output-directory=%s', output_directory)
-
-  if not tool_prefix and output_directory:
-    # Auto-detect from build_vars.txt
-    build_vars_path = os.path.join(output_directory, 'build_vars.txt')
-    if os.path.exists(build_vars_path):
-      with open(build_vars_path) as f:
-        build_vars = dict(l.rstrip().split('=', 1) for l in f if '=' in l)
-      logging.debug('Found --tool-prefix from build_vars.txt')
-      tool_prefix = build_vars['android_tool_prefix']
-
-  if os.path.sep not in tool_prefix:
-    full_path = distutils.spawn.find_executable(tool_prefix + 'c++filt')
-  else:
-    full_path = tool_prefix + 'c++filt'
-
-  if not os.path.isfile(full_path):
-    raise Exception('Bad --tool-prefix. Path not found: %s' % full_path)
-  logging.info('Using --tool-prefix=%s', tool_prefix)
-  return tool_prefix
-
-
-def AnalyzeWithArgs(args):
-  return Analyze(args.input_file, args.output_directory, args.tool_prefix)
-
-
-def Analyze(path, output_directory=None, tool_prefix=''):
-  if _EndsWithMaybeGz(path, '.size'):
-    logging.info('Loading cached results.')
-    with _OpenMaybeGz(path) as f:
-      result = _LoadResults(f)
-  elif not _EndsWithMaybeGz(path, '.map'):
-    raise Exception('Expected input to be a .map or a .size')
-  else:
-    # Verify tool_prefix early.
-    tool_prefix = _DetectToolPrefix(tool_prefix, path, output_directory)
-
-    with _OpenMaybeGz(path) as map_file:
-      result = mapfileparser.MapFileParser().Parse(map_file)
-
-    # Map file for some reason doesn't unmangle all names.
-    logging.info('Calculating padding')
-    _RemoveDuplicatesAndCalculatePadding(result.symbol_group)
-    # Unmangle prints its own log statement.
-    _UnmangleRemainingSymbols(result.symbol_group, tool_prefix)
-    # Resolve paths prints its own log statement.
-    logging.info('Normalizing names')
-    _NormalizeNames(result.symbol_group)
-    logging.info('Normalizing paths')
-    _NormalizeObjectPaths(result.symbol_group)
-
-  if logging.getLogger().isEnabledFor(logging.INFO):
-    _PrintStats(result, lambda l: logging.info(l.rstrip()))
-  logging.info('Finished analyzing %d symbols', len(result.symbol_group))
-  return result
-
-
-def main():
-  parser = argparse.ArgumentParser()
-  parser.add_argument('--output', required=True,
-                      help='Path to store results. Must end in .size or '
-                           '.size.gz')
-  AddOptions(parser)
-  args = helpers.AddCommonOptionsAndParseArgs(parser)
-  if not _EndsWithMaybeGz(args.output, '.size'):
-    raise Exception('--output must end with .size or .size.gz')
-
-  result = AnalyzeWithArgs(args)
-  logging.info('Saving result to %s', args.output)
-  with _OpenMaybeGz(args.output, 'wb') as f:
-    _SaveResult(result, f)
-
-  logging.info('Done')
-
-
-if __name__ == '__main__':
-  main()