So that one can get an skeleton from where a function can be
reimplemented, or a probe can be written to attach to a tracepoint.
Right now it will only expand the types for
struct/union/typedef/enumeration types, but it is a good start.
[acme@doppio pahole]$ pfunct --expand_types --function inet6_ioctl ipv6.ko > a.c
[acme@doppio pahole]$ echo "int main(void) { return 0; }" >> a.c
[acme@doppio pahole]$ gcc -Wall -g a.c -o a
[acme@doppio pahole]$ grep ^#include a.c
[acme@doppio pahole]$
No errors, no includes.
This is present in ctracer, where we don't want to _require_ any header
files, just the object file with the function we want to probe. From
there we get the function signature, and reconstruct the types needed to
access members of structs passed as parameters.
We still need to add padding to reconstruct __attribute__ alignment
effects.
Also, if we can detect what are the exact members accessed in the probe,
we can reconstruct just what is needed to access those members,
hopefully reducing the time needed for gcc to digest the resulting
source code. And also reducing the size of the output, which can
hopefully be interesting to help focus on what the probe is doing.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When we are looking for members of some type in all CUs it may be that in
some CU we don't have the full type, but just a declaration.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can go on adding more config knobs without requiring adding new
parameters to lots of functions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Suggested by: Jeff Muizelaar.
And it was wrong in the sense that the help was like:
--executable|-e FILE <SNIP lots of other options> FILE
So now its a bit redundant, like:
--executable|-e FILE <SNIP lots of other options> -e FILE
But as this is the most common usage pattern, give it more visibility.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
[acme@mica pahole]$ pahole lala
pahole: Permission denied
[acme@mica pahole]$ pahole foo
pahole: No such file or directory
[acme@mica pahole]$ pahole ctracer.c
pahole: couldn't load DWARF info from ctracer.c
[acme@mica pahole]$
Thanks to Matthew Wilcox for noticing how lame it was :-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
So that in tools like ctracer we can print to a file, most of the tools just
pass stdout, keeping the previous behaviour.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Using export CFLAGS="-Wall -Wfatal-errors -Wformat=2 -Wsequence-point -Wextra
-Wno-parentheses -g", suggested by Davi Arnault, amazing how cruft piles up
when one is not looking ;)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And since there are no external users now, just unexport it, ditto
for tag__print_decl_info.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Its up to its callers, that will be moot soon as tag__print will call
function__print and as it already prints the decl info it'll be just a matter
of making all the function__print callers call tag__print instead and then
function__print will be unexported.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Sortof, mostly works, but still has a problem where the abstract origin is not
being found, but for now its ok to keep the bandaid, everything works as
before, there are more important things to do right now.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
We have to check for a possible alias (abstract origin attribute) and handle
that when we want the function name, if it is an alias, do the lookup and cache
the result in ->name, that after all doesn't have a value in the first place.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
As they already look just for DW_TAG_structure_type. Also make it return a
struct tag to avoid having to cast it back and forth too much.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Out of struct typedef_tag, that now becomes the superclass of struct class, and
that also will be for struct enumeration, struct union_type and then finally
for struct struct_type, when struct class finally dies.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
By having its own class, struct typedef_tag.
As it, as structs, unions and enums have a common part, the node and visited
fields, required when emitting its definitions there is an opportunity for
consolidation, that will be explored when adding the specific classes for
DW_TAG_enumeration & DW_TAG_union.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Almost mirroring the DWARF on-disk linkage on memory, more to come before
getting over these simplification refactorings.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
And fix its usage in ctracer and pfunct, guess the cmake adoption
is still a little problematic...
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Will be reused when handling DW_TAG_subprogram_type more comprehensively, in
the upcoming csets.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
So that we can extract bits from one and combine it bits from other instances,
like we'll do in ctracer, where we want to have a cus instance just to get the
kprobes definitions and forward declarations but not handle the methods in it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
So that we can load many object files, that is what the next csets will
do, to recursively look for files with debug info in a build tree, such
as the kernel one.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
To simplify the callsites and make implementing the same thing on the other
dwarves (prefcnt, pfunct, etc) easy.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
To represent DW_TAG_lexical_block, for now just group the lists of
labels, inline expansions and variables, struct function now has
the root of the tree as ->lexblock.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Introducing function__print_body, that orders the tags in a function by the
souce code line where it was declared or inlined.
This finally takes advantage of the struct tag "superclass", more to come in
the form of lexical blocks and goto labels.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
I.e. the functions declared as inline but not inlined by the compiler
DW_AT_inline with DW_INL_declared_not_inlined value.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Arnaldo Carvalho de Melo
Arnaldo Carvalho de Melo
Davi Arnaut
Arnaldo Carvalho de Melo