[Patch][Checkstack] Do not hide small stackframes

From: JÃrn Engel
Date: Tue Nov 04 2008 - 14:59:19 EST


On Tue, 4 November 2008 18:35:24 +0100, JÃrn Engel wrote:
> On Tue, 4 November 2008 17:06:28 +0100, Matthieu CASTET wrote:
> >
> > 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.

JÃrn

--
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: JÃrn Engel <joern@xxxxxxxxx>
---

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;
--
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