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

tools/binary_size/binary_size_utils.py

-# 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.
-
-"""Common utilities for tools that deal with binary size information.
-"""
-
-import logging
-import re
-
-
-def ParseNm(nm_lines):
-  """Parse nm output, returning data for all relevant (to binary size)
-  symbols and ignoring the rest.
-
-  Args:
-      nm_lines: an iterable over lines of nm output.
-
-  Yields:
-      (symbol name, symbol type, symbol size, source file path).
-
-      Path may be None if nm couldn't figure out the source file.
-  """
-
-  # Match lines with size, symbol, optional location, optional discriminator
-  sym_re = re.compile(r'^([0-9a-f]{8,}) ' # address (8+ hex digits)
-                      '([0-9a-f]{8,}) ' # size (8+ hex digits)
-                      '(.) ' # symbol type, one character
-                      '([^\t]+)' # symbol name, separated from next by tab
-                      '(?:\t(.*):[\d\?]+)?.*$') # location
-  # Match lines with addr but no size.
-  addr_re = re.compile(r'^[0-9a-f]{8,} (.) ([^\t]+)(?:\t.*)?$')
-  # Match lines that don't have an address at all -- typically external symbols.
-  noaddr_re = re.compile(r'^ {8,} (.) (.*)$')
-  # Match lines with no symbol name, only addr and type
-  addr_only_re = re.compile(r'^[0-9a-f]{8,} (.)$')
-
-  seen_lines = set()
-  for line in nm_lines:
-    line = line.rstrip()
-    if line in seen_lines:
-      # nm outputs identical lines at times. We don't want to treat
-      # those as distinct symbols because that would make no sense.
-      continue
-    seen_lines.add(line)
-    match = sym_re.match(line)
-    if match:
-      address, size, sym_type, sym = match.groups()[0:4]
-      size = int(size, 16)
-      if sym_type in ('B', 'b'):
-        continue  # skip all BSS for now.
-      path = match.group(5)
-      yield sym, sym_type, size, path, address
-      continue
-    match = addr_re.match(line)
-    if match:
-      # sym_type, sym = match.groups()[0:2]
-      continue  # No size == we don't care.
-    match = noaddr_re.match(line)
-    if match:
-      sym_type, sym = match.groups()
-      if sym_type in ('U', 'w'):
-        continue  # external or weak symbol
-    match = addr_only_re.match(line)
-    if match:
-      continue  # Nothing to do.
-
-
-    # If we reach this part of the loop, there was something in the
-    # line that we didn't expect or recognize.
-    logging.warning('nm output parser failed to parse: %s', repr(line))