| #!/usr/bin/env python |
| # Copyright (c) 2011 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. |
| |
| """Prints a report of symbols stripped by the linker due to being unused. |
| |
| To use, build with these linker flags: |
| -Wl,--gc-sections |
| -Wl,--print-gc-sections |
| the first one is the default in Release; search build/common.gypi for it |
| and to see where to add the other. |
| |
| Then build, saving the output into a file: |
| make chrome 2>&1 | tee buildlog |
| and run this script on it: |
| ./tools/unused-symbols-report.py buildlog > report.html |
| """ |
| |
| import cgi |
| import optparse |
| import os |
| import re |
| import subprocess |
| import sys |
| |
| cppfilt_proc = None |
| def Demangle(sym): |
| """Demangle a C++ symbol by passing it through c++filt.""" |
| global cppfilt_proc |
| if cppfilt_proc is None: |
| cppfilt_proc = subprocess.Popen(['c++filt'], stdin=subprocess.PIPE, |
| stdout=subprocess.PIPE) |
| print >>cppfilt_proc.stdin, sym |
| return cppfilt_proc.stdout.readline().strip() |
| |
| |
| def Unyuck(sym): |
| """Attempt to prettify a C++ symbol by some basic heuristics.""" |
| sym = sym.replace('std::basic_string<char, std::char_traits<char>, ' |
| 'std::allocator<char> >', 'std::string') |
| sym = sym.replace('std::basic_string<wchar_t, std::char_traits<wchar_t>, ' |
| 'std::allocator<wchar_t> >', 'std::wstring') |
| sym = sym.replace('std::basic_string<unsigned short, ' |
| 'base::string16_char_traits, ' |
| 'std::allocator<unsigned short> >', 'string16') |
| sym = re.sub(r', std::allocator<\S+\s+>', '', sym) |
| return sym |
| |
| |
| def Parse(input, skip_paths=None, only_paths=None): |
| """Parse the --print-gc-sections build output. |
| |
| Args: |
| input: iterable over the lines of the build output |
| |
| Yields: |
| (target name, path to .o file, demangled symbol) |
| """ |
| symbol_re = re.compile(r"'\.text\.(\S+)' in file '(\S+)'$") |
| path_re = re.compile(r"^out/[^/]+/[^/]+/([^/]+)/(.*)$") |
| for line in input: |
| match = symbol_re.search(line) |
| if not match: |
| continue |
| symbol, path = match.groups() |
| symbol = Unyuck(Demangle(symbol)) |
| path = os.path.normpath(path) |
| if skip_paths and skip_paths in path: |
| continue |
| if only_paths and only_paths not in path: |
| continue |
| match = path_re.match(path) |
| if not match: |
| print >>sys.stderr, "Skipping weird path", path |
| continue |
| target, path = match.groups() |
| yield target, path, symbol |
| |
| |
| # HTML header for our output page. |
| TEMPLATE_HEADER = """<!DOCTYPE html> |
| <head> |
| <style> |
| body { |
| font-family: sans-serif; |
| font-size: 0.8em; |
| } |
| h1, h2 { |
| font-weight: normal; |
| margin: 0.5em 0; |
| } |
| h2 { |
| margin-top: 1em; |
| } |
| tr:hover { |
| background: #eee; |
| } |
| .permalink { |
| padding-left: 1ex; |
| font-size: 80%; |
| text-decoration: none; |
| color: #ccc; |
| } |
| .symbol { |
| font-family: WebKitWorkAround, monospace; |
| margin-left: 4ex; |
| text-indent: -4ex; |
| padding: 0.5ex 1ex; |
| } |
| .file { |
| padding: 0.5ex 1ex; |
| padding-left: 2ex; |
| font-family: WebKitWorkAround, monospace; |
| font-size: 90%; |
| color: #777; |
| } |
| </style> |
| </head> |
| <body> |
| <h1>chrome symbols deleted at link time</h1> |
| """ |
| |
| |
| def Output(iter): |
| """Print HTML given an iterable of (target, path, symbol) tuples.""" |
| targets = {} |
| for target, path, symbol in iter: |
| entries = targets.setdefault(target, []) |
| entries.append((symbol, path)) |
| |
| print TEMPLATE_HEADER |
| print "<p>jump to target:" |
| print "<select = this.value'>" |
| for target in sorted(targets.keys()): |
| print "<option>%s</option>" % target |
| print "</select></p>" |
| |
| for target in sorted(targets.keys()): |
| print "<h2>%s" % target |
| print "<a class=permalink href='#%s' name='%s'>#</a>" % (target, target) |
| print "</h2>" |
| print "<table width=100% cellspacing=0>" |
| for symbol, path in sorted(targets[target]): |
| htmlsymbol = cgi.escape(symbol).replace('::', '::<wbr>') |
| print "<tr><td><div class=symbol>%s</div></td>" % htmlsymbol |
| print "<td valign=top><div class=file>%s</div></td></tr>" % path |
| print "</table>" |
| |
| |
| def main(): |
| parser = optparse.OptionParser(usage='%prog [options] buildoutput\n\n' + |
| __doc__) |
| parser.add_option("--skip-paths", metavar="STR", default="third_party", |
| help="skip paths matching STR [default=%default]") |
| parser.add_option("--only-paths", metavar="STR", |
| help="only include paths matching STR [default=%default]") |
| opts, args = parser.parse_args() |
| |
| if len(args) < 1: |
| parser.print_help() |
| sys.exit(1) |
| |
| iter = Parse(open(args[0]), |
| skip_paths=opts.skip_paths, |
| only_paths=opts.only_paths) |
| Output(iter) |
| |
| |
| if __name__ == '__main__': |
| main() |