checkstack.pl

#!/usr/bin/env perl
# SPDX-License-Identifier: GPL-2.0

#	Check the stack usage of functions
#
#	Copyright Joern Engel <joern@lazybastard.org>
#	Inspired by Linus Torvalds
#	Original idea maybe from Keith Owens
#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
#	IA64 port via Andreas Dilger
#	Arm port by Holger Schurig
#	sh64 port by Paul Mundt
#	Random bits by Matt Mackall <mpm@selenic.com>
#	M68k port by Geert Uytterhoeven and Andreas Schwab
#	AArch64, PARISC ports by Kyle McMartin
#	sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
#	ppc64le port by Breno Leitao <leitao@debian.org>
#
#	Usage:
#	objdump -d vmlinux | scripts/checkstack.pl [arch]
#
#	TODO :	Port to all architectures (one regex per arch)

use strict;

# check for arch
#
# $re is used for two matches:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the size of the stack growth
#
# $dre is similar, but for dynamic stack redutions:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the dynamic amount of the stack growth
#
# use anything else and feel the pain ;)
my (@stack, $re, $dre, $x, $xs, $funcre);
{
	my $arch = shift;
	if ($arch eq "") {
		$arch = `uname -m`;
		chomp($arch);
	}

	$x	= "[0-9a-f]";	# hex character
	$xs	= "[0-9a-f ]";	# hex character or space
	$funcre = qr/^$x* <(.*)>:$/;
	if ($arch =~ '^(aarch|arm)64$') {
		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
		#a110:       d11643ff        sub     sp, sp, #0x590
		$re = qr/^.*stp.*sp, \#-([0-9]{1,8})\]\!/o;
		$dre = qr/^.*sub.*sp, sp, #(0x$x{1,8})/o;
	} elsif ($arch eq 'arm') {
		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
		$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
		# or
		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
	} elsif ($arch eq 'ia64') {
		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
	} elsif ($arch eq 'm68k') {
		#    2b6c:       4e56 fb70       linkw %fp,#-1168
		#  1df770:       defc ffe4       addaw #-28,%sp
		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
	} elsif ($arch eq 'mips64') {