arm checkstack
Hi,
I wonder why the arm version of checkstack only catch stack size >= 300 and < 10000 [1].
Why doesn't it use ".*sub.*sp, sp, #([0-9]{1,8})" to catch all stack usage ?
Matthieu
[1]
$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
Quoted 4 lines · Matthieu CASTET
I wonder why the arm version of checkstack only catch stack size >= 300 and < 10000 [1].
Why doesn't it use ".*sub.*sp, sp, #([0-9]{1,8})" to catch all stack usage ?
Looks like a bug. And it further looks like Holger just copied what everyone else did at the time. And the one who started this strange pattern was: Arnd.
Arnd, did you have a good reason for choosing the pattern?
Quoted 2 lines
[1]
$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
Jörn
Signature · 3 lines
The cost of changing business rules is much more expensive for software than for a secretaty. -- unknown
PATCH 1/1 Do not hide small stackframes
Quoted 11 lines · Jörn Engel
Quoted 4 lines · Matthieu CASTET
I wonder why the arm version of checkstack only catch stack size >= 300 and < 10000 [1].
Why doesn't it use ".*sub.*sp, sp, #([0-9]{1,8})" to catch all stack usage ?Looks like a bug. And it further looks like Holger just copied what everyone else did at the time. And the one who started this strange pattern was: Arnd.
Arnd, did you have a good reason for choosing the pattern?
Assuming you didn't, the patch below should print all(*) stackframes for all architectures.
(*) Stack frames below 100 bytes are ignored, by virtue of
next if ($size < 100);
This is imo preferrable as it is architecture-independent and easier to spot. The fact that noone noticed the 300 byte effect for five years (or thereabout) speaks volumes.
Jörn
Signature · 62 lines
You ain't got no problem, Jules. I'm on the motherfucker. Go back in there, chill them niggers out and wait for the Wolf, who should be coming directly. -- Marsellus Wallace The regex for s390 - and several other architectures that copied from s390 - silently ignored stack frames below 300 and above 10000 bytes. Signed-off-by: Jörn Engel <[email protected]> --- scripts/checkstack.pl | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- debuggerhead/scripts/checkstack.pl~checkstack 2008-03-05 12:14:05.000000000 +0100 +++ debuggerhead/scripts/checkstack.pl 2008-11-04 20:38:08.000000000 +0100 @@ -38,7 +38,7 @@ my (@stack, $re, $x, $xs); $xs = "[0-9a-f ]"; # hex character or space if ($arch eq 'arm') { #c0008ffc: e24dd064 sub sp, sp, #100 ; 0x64 - $re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o; + $re = qr/.*sub.*sp, sp, #([0-9]{1,8})/o; } elsif ($arch eq 'avr32') { #8000008a: 20 1d sub sp,4 #80000ca8: fa cd 05 b0 sub sp,sp,1456 @@ -51,17 +51,17 @@ my (@stack, $re, $x, $xs); $re = qr/^.*[as][du][db] \$(0x$x{1,8}),\%rsp$/o; } elsif ($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; + $re = qr/.*adds.*r12=-([0-9]{1,8}),r12/o; } elsif ($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') { #8800402c: 67bdfff0 daddiu sp,sp,-16 - $re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o; + $re = qr/.*daddiu.*sp,sp,-([0-9]{1,8})/o; } elsif ($arch eq 'mips') { #88003254: 27bdffe0 addiu sp,sp,-32 - $re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o; + $re = qr/.*addiu.*sp,sp,-([0-9]{1,8})/o; } elsif ($arch eq 'parisc' || $arch eq 'parisc64') { $re = qr/.*ldo ($x{1,8})\(sp\),sp/o; } elsif ($arch eq 'ppc') { @@ -74,13 +74,13 @@ my (@stack, $re, $x, $xs); $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o; } elsif ($arch =~ /^s390x?$/) { # 11160: a7 fb ff 60 aghi %r15,-160 - $re = qr/.*ag?hi.*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})/o; + $re = qr/.*ag?hi.*\%r15,-([0-9]{1,8})/o; } elsif ($arch =~ /^sh64$/) { #XXX: we only check for the immediate case presently, # though we will want to check for the movi/sub # pair for larger users. -- PFM. #a00048e0: d4fc40f0 addi.l r15,-240,r15 - $re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o; + $re = qr/.*addi\.l.*r15,-([0-9]{1,8}),r15/o; } elsif ($arch =~ /^blackfin$/) { # 0: 00 e8 38 01 LINK 0x4e0; $re = qr/.*[[:space:]]LINK[[:space:]]*(0x$x{1,8})/o;
Quoted 6 lines · Jörn Engel
Quoted 4 lines · Matthieu CASTET
I wonder why the arm version of checkstack only catch stack size >= 300 and < 10000 [1].
Why doesn't it use ".*sub.*sp, sp, #([0-9]{1,8})" to catch all stack usage ?
Quoted 6 lines
Looks like a bug. And it further looks like Holger just copied what everyone else did at the time. And the one who started this strange pattern was: Arnd.
Arnd, did you have a good reason for choosing the pattern?
don't really remember what I thought back then. Probably I tried to filter out any function lower than 300 bytes as early as possible and did not think of the >= 10000 case.
Arnd <><