xref: /openbmc/linux/scripts/checkstack.pl (revision 82e6fdd6)
1#!/usr/bin/env perl
2# SPDX-License-Identifier: GPL-2.0
3
4#	Check the stack usage of functions
5#
6#	Copyright Joern Engel <joern@lazybastard.org>
7#	Inspired by Linus Torvalds
8#	Original idea maybe from Keith Owens
9#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
10#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
11#	IA64 port via Andreas Dilger
12#	Arm port by Holger Schurig
13#	sh64 port by Paul Mundt
14#	Random bits by Matt Mackall <mpm@selenic.com>
15#	M68k port by Geert Uytterhoeven and Andreas Schwab
16#	AArch64, PARISC ports by Kyle McMartin
17#	sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
18#
19#	Usage:
20#	objdump -d vmlinux | scripts/checkstack.pl [arch]
21#
22#	TODO :	Port to all architectures (one regex per arch)
23
24use strict;
25
26# check for arch
27#
28# $re is used for two matches:
29# $& (whole re) matches the complete objdump line with the stack growth
30# $1 (first bracket) matches the size of the stack growth
31#
32# $dre is similar, but for dynamic stack redutions:
33# $& (whole re) matches the complete objdump line with the stack growth
34# $1 (first bracket) matches the dynamic amount of the stack growth
35#
36# use anything else and feel the pain ;)
37my (@stack, $re, $dre, $x, $xs, $funcre);
38{
39	my $arch = shift;
40	if ($arch eq "") {
41		$arch = `uname -m`;
42		chomp($arch);
43	}
44
45	$x	= "[0-9a-f]";	# hex character
46	$xs	= "[0-9a-f ]";	# hex character or space
47	$funcre = qr/^$x* <(.*)>:$/;
48	if ($arch eq 'aarch64') {
49		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp,#-80]!
50		$re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
51	} elsif ($arch eq 'arm') {
52		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
53		$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
54	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
55		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
56		# or
57		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
58		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
59		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
60	} elsif ($arch eq 'ia64') {
61		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
62		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
63	} elsif ($arch eq 'm68k') {
64		#    2b6c:       4e56 fb70       linkw %fp,#-1168
65		#  1df770:       defc ffe4       addaw #-28,%sp
66		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
67	} elsif ($arch eq 'metag') {
68		#400026fc:       40 00 00 82     ADD       A0StP,A0StP,#0x8
69		$re = qr/.*ADD.*A0StP,A0StP,\#(0x$x{1,8})/o;
70		$funcre = qr/^$x* <[^\$](.*)>:$/;
71	} elsif ($arch eq 'mips64') {
72		#8800402c:       67bdfff0        daddiu  sp,sp,-16
73		$re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
74	} elsif ($arch eq 'mips') {
75		#88003254:       27bdffe0        addiu   sp,sp,-32
76		$re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
77	} elsif ($arch eq 'nios2') {
78		#25a8:	defffb04 	addi	sp,sp,-20
79		$re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
80	} elsif ($arch eq 'openrisc') {
81		# c000043c:       9c 21 fe f0     l.addi r1,r1,-272
82		$re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
83	} elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
84		$re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
85	} elsif ($arch eq 'ppc') {
86		#c00029f4:       94 21 ff 30     stwu    r1,-208(r1)
87		$re = qr/.*stwu.*r1,-($x{1,8})\(r1\)/o;
88	} elsif ($arch eq 'ppc64') {
89		#XXX
90		$re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
91	} elsif ($arch eq 'powerpc') {
92		$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
93	} elsif ($arch =~ /^s390x?$/) {
94		#   11160:       a7 fb ff 60             aghi   %r15,-160
95		# or
96		#  100092:	 e3 f0 ff c8 ff 71	 lay	 %r15,-56(%r15)
97		$re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
98		      (?:\(\%r15\))?$/ox;
99	} elsif ($arch =~ /^sh64$/) {
100		#XXX: we only check for the immediate case presently,
101		#     though we will want to check for the movi/sub
102		#     pair for larger users. -- PFM.
103		#a00048e0:       d4fc40f0        addi.l  r15,-240,r15
104		$re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
105	} elsif ($arch =~ /^blackfin$/) {
106		#   0:   00 e8 38 01     LINK 0x4e0;
107		$re = qr/.*[[:space:]]LINK[[:space:]]*(0x$x{1,8})/o;
108	} elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
109		# f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
110		$re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
111	} else {
112		print("wrong or unknown architecture \"$arch\"\n");
113		exit
114	}
115}
116
117#
118# main()
119#
120my ($func, $file, $lastslash);
121
122while (my $line = <STDIN>) {
123	if ($line =~ m/$funcre/) {
124		$func = $1;
125	}
126	elsif ($line =~ m/(.*):\s*file format/) {
127		$file = $1;
128		$file =~ s/\.ko//;
129		$lastslash = rindex($file, "/");
130		if ($lastslash != -1) {
131			$file = substr($file, $lastslash + 1);
132		}
133	}
134	elsif ($line =~ m/$re/) {
135		my $size = $1;
136		$size = hex($size) if ($size =~ /^0x/);
137
138		if ($size > 0xf0000000) {
139			$size = - $size;
140			$size += 0x80000000;
141			$size += 0x80000000;
142		}
143		next if ($size > 0x10000000);
144
145		next if $line !~ m/^($xs*)/;
146		my $addr = $1;
147		$addr =~ s/ /0/g;
148		$addr = "0x$addr";
149
150		my $intro = "$addr $func [$file]:";
151		my $padlen = 56 - length($intro);
152		while ($padlen > 0) {
153			$intro .= '	';
154			$padlen -= 8;
155		}
156		next if ($size < 100);
157		push @stack, "$intro$size\n";
158	}
159	elsif (defined $dre && $line =~ m/$dre/) {
160		my $size = "Dynamic ($1)";
161
162		next if $line !~ m/^($xs*)/;
163		my $addr = $1;
164		$addr =~ s/ /0/g;
165		$addr = "0x$addr";
166
167		my $intro = "$addr $func [$file]:";
168		my $padlen = 56 - length($intro);
169		while ($padlen > 0) {
170			$intro .= '	';
171			$padlen -= 8;
172		}
173		push @stack, "$intro$size\n";
174	}
175}
176
177# Sort output by size (last field)
178print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;
179