xref: /llvm-project/compiler-rt/lib/fuzzer/scripts/unbalanced_allocs.py (revision f98ee40f4b5d7474fc67e82824bf6abbaedb7b1c) 
1#!/usr/bin/env python
2# ===- lib/fuzzer/scripts/unbalanced_allocs.py ------------------------------===#
3#
4# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5# See https://llvm.org/LICENSE.txt for license information.
6# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7#
8# ===------------------------------------------------------------------------===#
9#
10# Post-process -trace_malloc=2 output and printout only allocations and frees
11# unbalanced inside of fuzzer runs.
12# Usage:
13#   my_fuzzer -trace_malloc=2 -runs=10 2>&1 | unbalanced_allocs.py -skip=5
14#
15# ===------------------------------------------------------------------------===#
16
17import argparse
18import sys
19
20_skip = 0
21
22
23def PrintStack(line, stack):
24    global _skip
25    if _skip > 0:
26        return
27    print("Unbalanced " + line.rstrip())
28    for l in stack:
29        print(l.rstrip())
30
31
32def ProcessStack(line, f):
33    stack = []
34    while line and line.startswith("    #"):
35        stack += [line]
36        line = f.readline()
37    return line, stack
38
39
40def ProcessFree(line, f, allocs):
41    if not line.startswith("FREE["):
42        return f.readline()
43
44    addr = int(line.split()[1], 16)
45    next_line, stack = ProcessStack(f.readline(), f)
46    if addr in allocs:
47        del allocs[addr]
48    else:
49        PrintStack(line, stack)
50    return next_line
51
52
53def ProcessMalloc(line, f, allocs):
54    if not line.startswith("MALLOC["):
55        return ProcessFree(line, f, allocs)
56
57    addr = int(line.split()[1], 16)
58    assert not addr in allocs
59
60    next_line, stack = ProcessStack(f.readline(), f)
61    allocs[addr] = (line, stack)
62    return next_line
63
64
65def ProcessRun(line, f):
66    if not line.startswith("MallocFreeTracer: START"):
67        return ProcessMalloc(line, f, {})
68
69    allocs = {}
70    print(line.rstrip())
71    line = f.readline()
72    while line:
73        if line.startswith("MallocFreeTracer: STOP"):
74            global _skip
75            _skip = _skip - 1
76            for _, (l, s) in allocs.items():
77                PrintStack(l, s)
78            print(line.rstrip())
79            return f.readline()
80        line = ProcessMalloc(line, f, allocs)
81    return line
82
83
84def ProcessFile(f):
85    line = f.readline()
86    while line:
87        line = ProcessRun(line, f)
88
89
90def main(argv):
91    parser = argparse.ArgumentParser()
92    parser.add_argument("--skip", default=0, help="number of runs to ignore")
93    args = parser.parse_args()
94    global _skip
95    _skip = int(args.skip) + 1
96    ProcessFile(sys.stdin)
97
98
99if __name__ == "__main__":
100    main(sys.argv)
101