1#!/usr/bin/env python3
2# SPDX-License-Identifier: GPL-2.0
3#
4# Usage: unwcheck.py FILE
5#
6# This script checks the unwind info of each function in file FILE
7# and verifies that the sum of the region-lengths matches the total
8# length of the function.
9#
10# Based on a shell/awk script originally written by Harish Patil,
11# which was converted to Perl by Matthew Chapman, which was converted
12# to Python by David Mosberger.
13#
14import os
15import re
16import sys
17
18if len(sys.argv) != 2:
19    print("Usage: %s FILE" % sys.argv[0])
20    sys.exit(2)
21
22readelf = os.getenv("READELF", "readelf")
23
24start_pattern = re.compile("<([^>]*)>: \[0x([0-9a-f]+)-0x([0-9a-f]+)\]")
25rlen_pattern  = re.compile(".*rlen=([0-9]+)")
26
27def check_func (func, slots, rlen_sum):
28    if slots != rlen_sum:
29        global num_errors
30        num_errors += 1
31        if not func: func = "[%#x-%#x]" % (start, end)
32        print("ERROR: %s: %lu slots, total region length = %lu" % (func, slots, rlen_sum))
33    return
34
35num_funcs = 0
36num_errors = 0
37func = False
38slots = 0
39rlen_sum = 0
40for line in os.popen("%s -u %s" % (readelf, sys.argv[1])):
41    m = start_pattern.match(line)
42    if m:
43        check_func(func, slots, rlen_sum)
44
45        func  = m.group(1)
46        start = int(m.group(2), 16)
47        end   = int(m.group(3), 16)
48        slots = 3 * (end - start) / 16
49        rlen_sum = 0
50        num_funcs += 1
51    else:
52        m = rlen_pattern.match(line)
53        if m:
54            rlen_sum += int(m.group(1))
55check_func(func, slots, rlen_sum)
56
57if num_errors == 0:
58    print("No errors detected in %u functions." % num_funcs)
59else:
60    if num_errors > 1:
61        err="errors"
62    else:
63        err="error"
64    print("%u %s detected in %u functions." % (num_errors, err, num_funcs))
65    sys.exit(1)
66