V1 of //tools/binary_size rewrite

tools/binary_size/parsers.py

+# 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.
+
+import logging
+
+import symbols
+
+
+class ParseResult(object):
+  """Return value for Parse() methods."""
+  def __init__(self, symbol_list, section_sizes=None):
+    self.symbol_group = symbols.SymbolGroup(symbol_list)
+    self.section_sizes = section_sizes  # E.g. {'.text': 0}
+
+
+class MapFileParser(object):
+  """Parses a linker map file (tested only on files from gold linker)."""
+  # Map file writer for gold linker:
+  # https://github.com/gittup/binutils/blob/HEAD/gold/mapfile.cc
+
+  def __init__(self):
+    self._symbols = []
+    self._section_sizes = {}
+    self._lines = None
+
+  def Parse(self, lines):
+    """Parses a linker map file.
+
+    Args:
+      lines: Iterable of lines.
+
+    Returns:
+      A ParseResult object.
+    """
+    self._lines = iter(lines)
+    logging.info('Parsing common symbols')
+    self._ParseCommonSymbols()
+    logging.debug('.bss common entries: %d', len(self._symbols))
+    logging.info('Parsing section symbols')
+    self._ParseSections()
+    return ParseResult(self._symbols, self._section_sizes)
+
+  def _SkipToLineWithPrefix(self, prefix):
+    for l in self._lines:
+      if l.startswith(prefix):
+        return l
+
+  def _ParsePossiblyWrappedParts(self, line, count):
+    parts = line.split(None, count - 1)
+    if not parts:
+      return None
+    if len(parts) == count:

[estevenson, 2017/03/20 14:13:03]

nit: you could change this to: if len(parts) != count and only have one
parts[-1].rstrip() and return statement.

[agrieve, 2017/03/20 19:58:09]

Done.

+      parts[-1] = parts[-1].rstrip()
+      return parts
+
+    line = next(self._lines)
+    parts.extend(line.split(None, count - len(parts) - 1))
+    assert len(parts) == count, 'parts: ' + ' '.join(parts)
+    parts[-1] = parts[-1].rstrip()
+    return parts
+
+  def _ParseCommonSymbols(self):
+# Common symbol       size              file
+#
+# ff_cos_131072       0x40000           obj/third_party/<snip>
+# ff_cos_131072_fixed
+#                     0x20000           obj/third_party/<snip>
+    self._SkipToLineWithPrefix('Common symbol')
+    next(self._lines)  # Skip past blank line
+
+    name, size_str, path = None, None, None
+    for l in self._lines:
+      parts = self._ParsePossiblyWrappedParts(l, 3)
+      if not parts:
+        break
+      name, size_str, path = parts
+      self._symbols.append(
+          symbols.Symbol('.bss', 0, int(size_str[2:], 16), name, path))
+
+  def _ParseSections(self):
+# .text           0x0028c600  0x22d3468
+#  .text.startup._GLOBAL__sub_I_bbr_sender.cc
+#                 0x0028c600       0x38 obj/net/net/bbr_sender.o
+#  .text._reset   0x00339d00       0xf0 obj/third_party/icu/icuuc/ucnv.o
+#  ** fill        0x0255fb00   0x02
+#  .text._ZN4base8AutoLockD2Ev
+#                 0x00290710        0xe obj/net/net/file_name.o
+#                 0x00290711                base::AutoLock::~AutoLock()
+#                 0x00290711                base::AutoLock::~AutoLock()
+# .text._ZNK5blink15LayoutBlockFlow31mustSeparateMarginAfterForChildERK...
+#                0xffffffffffffffff       0x46 obj/...
+#                0x006808e1                blink::LayoutBlockFlow::...
+# .bss
+#  .bss._ZGVZN11GrProcessor11initClassIDI10LightingFPEEvvE8kClassID
+#                0x02d4b294        0x4 obj/skia/skia/SkLightingShader.o
+#                0x02d4b294   guard variable for void GrProcessor::initClassID
+# .data           0x0028c600  0x22d3468
+#  .data.rel.ro._ZTVN3gvr7android19ScopedJavaGlobalRefIP12_jfloatArrayEE
+#                0x02d1e668       0x10 ../../third_party/.../libfoo.a(bar.o)
+#                0x02d1e668   vtable for gvr::android::GlobalRef<_jfloatArray*>
+#  ** merge strings
+#                 0x0255fb00   0x1f2424
+#  ** merge constants
+#                 0x0255fb00   0x8
+# ** common      0x02db5700   0x13ab48
+    self._SkipToLineWithPrefix('Memory map')
+    syms = self._symbols
+    while True:
+      line = self._SkipToLineWithPrefix('.')
+      if not line:
+        break
+      section_name = None
+      try:
+        # Parse section name and size.
+        parts = self._ParsePossiblyWrappedParts(line, 3)
+        if not parts:
+          break
+        section_name, address, size_str = parts
+        self._section_sizes[section_name] = int(size_str[2:], 16)
+        if (section_name in ('.bss', '.rodata', '.text') or
+            section_name.startswith('.data')):
+          logging.info('Parsing %s', section_name)
+          prefix_len = len(section_name) + 1  # + 1 for the trailing .
+          merge_symbol_start_address = 0
+          sym_count_at_start = len(syms)
+          line = next(self._lines)
+          # Parse section symbols.
+          while True:
+            if not line or line.isspace():
+              break
+            if line.startswith(' **'):
+              zero_index = line.find('0')
+              if zero_index == -1:
+                # Line wraps.
+                name = line.strip()
+                line = next(self._lines)
+              else:
+                # Line does not wrap.
+                name = line[:zero_index].strip()
+                line = line[zero_index:]
+              address_str, size_str = self._ParsePossiblyWrappedParts(line, 2)
+              line = next(self._lines)
+              # These bytes are already accounted for.
+              if name == '** common':
+                continue
+              address = int(address_str[2:], 16)
+              size = int(size_str[2:], 16)
+              path = None
+              syms.append(
+                  symbols.Symbol(section_name, address, size, name, path))
+            else:
+              # A normal symbol entry.
+              subsection_name, address_str, size_str, path = (
+                  self._ParsePossiblyWrappedParts(line, 4))
+              size = int(size_str[2:], 16)
+              if address_str == '0xffffffffffffffff':
+                # The section needs special handling (e.g., a merge section)
+                # It also generally has a large offset after it, so don't
+                # penalize the subsequent symbol for this gap (e.g. a 50kb gap).
+                # TODO(agrieve): Learn more about why this happens.
+                address = -1
+                if syms and syms[-1].address > 0:
+                  merge_symbol_start_address = syms[-1].end_address
+                merge_symbol_start_address += size
+              else:
+                address = int(address_str[2:], 16)
+                # Finish off active address gap / merge section.
+                if merge_symbol_start_address:
+                  merge_size = address - merge_symbol_start_address
+                  sym = symbols.Symbol(
+                      section_name, merge_symbol_start_address, merge_size,
+                      '** merged symbol: %s' % syms[-1].name, syms[-1].path)
+                  logging.debug('Merge symbol of size %d found at:\n  %r',
+                                merge_size, syms[-1])
+                  syms.append(sym)
+                  merge_symbol_start_address = 0
+              assert subsection_name.startswith(section_name), (
+                  'subsection name was: ' + subsection_name)
+              mangled_name = subsection_name[prefix_len:]
+              name = None
+              while True:
+                line = next(self._lines).rstrip()
+                if not line or line.startswith(' .'):
+                  break
+                # clang includes ** fill, but gcc does not.
+                if line.startswith(' ** fill'):
+                  # Alignment explicitly recorded in map file. Rather than
+                  # record padding based on these entries, we calculate it
+                  # using addresses. We do this because fill lines are not
+                  # present when compiling with gcc (only for clang).
+                  continue
+                elif line.startswith(' **'):
+                  break
+                elif name is None:
+                  address_str2, name = self._ParsePossiblyWrappedParts(line, 2)
+                  if address == -1:
+                    address = int(address_str2[2:], 16) - 1
+
+              # Merge sym with no second line showing real address.
+              if address == -1:
+                address = syms[-1].end_address
+              syms.append(symbols.Symbol(section_name, address, size,
+                                         name or mangled_name, path))
+          logging.debug('Symbol count for %s: %d', section_name,
+                        len(syms) - sym_count_at_start)
+      except:
+        logging.error('Problem line: %r', line)
+        logging.error('In section: %r', section_name)
+        raise