mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-24 05:11:16 +00:00
a80feff40b
MozReview-Commit-ID: 6B60uh4n2nY --HG-- extra : rebase_source : 4fd44789a9ee6376c72bae1132f73c81dd1eacbc
213 lines
8.0 KiB
Python
213 lines
8.0 KiB
Python
# vim: set ts=8 sts=4 et sw=4 tw=79:
|
|
# This Source Code Form is subject to the terms of the Mozilla Public
|
|
# License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
# ----------------------------------------------------------------------------
|
|
# All heap allocations in SpiderMonkey must go through js_malloc, js_calloc,
|
|
# js_realloc, and js_free. This is so that any embedder who uses a custom
|
|
# allocator (by defining JS_USE_CUSTOM_ALLOCATOR) will see all heap allocation
|
|
# go through that custom allocator.
|
|
#
|
|
# Therefore, the presence of any calls to "vanilla" allocation/free functions
|
|
# (e.g. malloc(), free()) is a bug.
|
|
#
|
|
# This script checks for the presence of such disallowed vanilla
|
|
# allocation/free function in SpiderMonkey when it's built as a library. It
|
|
# relies on |nm| from the GNU binutils, and so only works on Linux, but one
|
|
# platform is good enough to catch almost all violations.
|
|
#
|
|
# This checking is only 100% reliable in a JS_USE_CUSTOM_ALLOCATOR build in
|
|
# which the default definitions of js_malloc et al (in Utility.h) -- which call
|
|
# malloc et al -- are replaced with empty definitions. This is because the
|
|
# presence and possible inlining of the default js_malloc et al can cause
|
|
# malloc/calloc/realloc/free calls show up in unpredictable places.
|
|
#
|
|
# Unfortunately, that configuration cannot be tested on Mozilla's standard
|
|
# testing infrastructure. Instead, by default this script only tests that none
|
|
# of the other vanilla allocation/free functions (operator new, memalign, etc)
|
|
# are present. If given the --aggressive flag, it will also check for
|
|
# malloc/calloc/realloc/free.
|
|
#
|
|
# Note: We don't check for |operator delete| and |operator delete[]|. These
|
|
# can be present somehow due to virtual destructors, but this is not too
|
|
# because vanilla delete/delete[] calls don't make sense without corresponding
|
|
# vanilla new/new[] calls, and any explicit calls will be caught by Valgrind's
|
|
# mismatched alloc/free checking.
|
|
# ----------------------------------------------------------------------------
|
|
|
|
from __future__ import print_function
|
|
|
|
import argparse
|
|
import re
|
|
import subprocess
|
|
import sys
|
|
import buildconfig
|
|
|
|
# The obvious way to implement this script is to search for occurrences of
|
|
# malloc et al, succeed if none are found, and fail is some are found.
|
|
# However, "none are found" does not necessarily mean "none are present" --
|
|
# this script could be buggy. (Or the output format of |nm| might change in
|
|
# the future.)
|
|
#
|
|
# So jsutil.cpp deliberately contains a (never-called) function that contains a
|
|
# single use of all the vanilla allocation/free functions. And this script
|
|
# fails if it (a) finds uses of those functions in files other than jsutil.cpp,
|
|
# *or* (b) fails to find them in jsutil.cpp.
|
|
|
|
# Tracks overall success of the test.
|
|
has_failed = False
|
|
|
|
|
|
def fail(msg):
|
|
print('TEST-UNEXPECTED-FAIL | check_vanilla_allocations.py |', msg)
|
|
global has_failed
|
|
has_failed = True
|
|
|
|
|
|
def main():
|
|
parser = argparse.ArgumentParser()
|
|
parser.add_argument('--aggressive', action='store_true',
|
|
help='also check for malloc, calloc, realloc and free')
|
|
parser.add_argument('file', type=str,
|
|
help='name of the file to check')
|
|
args = parser.parse_args()
|
|
|
|
# Run |nm|. Options:
|
|
# -u: show only undefined symbols
|
|
# -C: demangle symbol names
|
|
# -A: show an object filename for each undefined symbol
|
|
nm = buildconfig.substs.get('NM') or 'nm'
|
|
cmd = [nm, '-u', '-C', '-A', args.file]
|
|
lines = subprocess.check_output(cmd, universal_newlines=True,
|
|
stderr=subprocess.PIPE).split('\n')
|
|
|
|
# alloc_fns contains all the vanilla allocation/free functions that we look
|
|
# for. Regexp chars are escaped appropriately.
|
|
|
|
alloc_fns = [
|
|
# Matches |operator new(unsigned T)|, where |T| is |int| or |long|.
|
|
r'operator new\(unsigned',
|
|
|
|
# Matches |operator new[](unsigned T)|, where |T| is |int| or |long|.
|
|
r'operator new\[\]\(unsigned',
|
|
|
|
r'memalign',
|
|
# These three aren't available on all Linux configurations.
|
|
# r'posix_memalign',
|
|
# r'aligned_alloc',
|
|
# r'valloc',
|
|
]
|
|
|
|
if args.aggressive:
|
|
alloc_fns += [
|
|
r'malloc',
|
|
r'calloc',
|
|
r'realloc',
|
|
r'free',
|
|
r'strdup'
|
|
]
|
|
|
|
# This is like alloc_fns, but regexp chars are not escaped.
|
|
alloc_fns_unescaped = [fn.translate(None, r'\\') for fn in alloc_fns]
|
|
|
|
# This regexp matches the relevant lines in the output of |nm|, which look
|
|
# like the following.
|
|
#
|
|
# js/src/libjs_static.a:jsutil.o: U malloc
|
|
#
|
|
alloc_fns_re = r'([^:/ ]+):\s+U (' + r'|'.join(alloc_fns) + r')'
|
|
|
|
# This tracks which allocation/free functions have been seen in jsutil.cpp.
|
|
jsutil_cpp = set([])
|
|
|
|
# Would it be helpful to emit detailed line number information after a failure?
|
|
emit_line_info = False
|
|
|
|
for line in lines:
|
|
m = re.search(alloc_fns_re, line)
|
|
if m is None:
|
|
continue
|
|
|
|
filename = m.group(1)
|
|
|
|
# The stdc++compat library has an implicit call to operator new in
|
|
# thread::_M_start_thread.
|
|
if 'stdc++compat' in filename:
|
|
continue
|
|
|
|
# The memory allocator code contains calls to memalign. These are ok, so
|
|
# we whitelist them.
|
|
if "_memory_" in filename:
|
|
continue
|
|
|
|
# Ignore the fuzzing code imported from m-c
|
|
if "Fuzzer" in filename:
|
|
continue
|
|
|
|
# Ignore the profiling pseudo-stack, since it needs to run even when
|
|
# SpiderMonkey's allocator isn't initialized.
|
|
if "ProfilingStack" in filename:
|
|
continue
|
|
|
|
fn = m.group(2)
|
|
if filename == 'jsutil.o':
|
|
jsutil_cpp.add(fn)
|
|
else:
|
|
# An allocation is present in a non-special file. Fail!
|
|
fail("'" + fn + "' present in " + filename)
|
|
# Try to give more precise information about the offending code.
|
|
emit_line_info = True
|
|
|
|
# Check that all functions we expect are used in jsutil.cpp. (This will
|
|
# fail if the function-detection code breaks at any point.)
|
|
for fn in alloc_fns_unescaped:
|
|
if fn not in jsutil_cpp:
|
|
fail("'" + fn + "' isn't used as expected in jsutil.cpp")
|
|
else:
|
|
jsutil_cpp.remove(fn)
|
|
|
|
# This should never happen, but check just in case.
|
|
if jsutil_cpp:
|
|
fail('unexpected allocation fns used in jsutil.cpp: ' +
|
|
', '.join(jsutil_cpp))
|
|
|
|
# If we found any improper references to allocation functions, try to use
|
|
# DWARF debug info to get more accurate line number information about the
|
|
# bad calls. This is a lot slower than 'nm -A', and it is not always
|
|
# precise when building with --enable-optimized.
|
|
if emit_line_info:
|
|
print('check_vanilla_allocations.py: Source lines with allocation calls:')
|
|
print('check_vanilla_allocations.py: Accurate in unoptimized builds; jsutil.cpp expected.')
|
|
|
|
# Run |nm|. Options:
|
|
# -u: show only undefined symbols
|
|
# -C: demangle symbol names
|
|
# -l: show line number information for each undefined symbol
|
|
cmd = ['nm', '-u', '-C', '-l', args.file]
|
|
lines = subprocess.check_output(cmd, universal_newlines=True,
|
|
stderr=subprocess.PIPE).split('\n')
|
|
|
|
# This regexp matches the relevant lines in the output of |nm -l|,
|
|
# which look like the following.
|
|
#
|
|
# U malloc jsutil.cpp:117
|
|
#
|
|
alloc_lines_re = r'U ((' + r'|'.join(alloc_fns) + r').*)\s+(\S+:\d+)$'
|
|
|
|
for line in lines:
|
|
m = re.search(alloc_lines_re, line)
|
|
if m:
|
|
print('check_vanilla_allocations.py:',
|
|
m.group(1), 'called at', m.group(3))
|
|
|
|
if has_failed:
|
|
sys.exit(1)
|
|
|
|
print('TEST-PASS | check_vanilla_allocations.py | ok')
|
|
sys.exit(0)
|
|
|
|
|
|
if __name__ == '__main__':
|
|
main()
|