Description by Mark Wielaard:
Its a more compact expression of struct field offsets. Jakub already
backported it to the 4.4 gcc in rawhide.
http://gcc.gnu.org/ml/gcc-patches/2009-07/msg00437.html It simply means
that when you try to get the field offset based on a
DW_AT_data_member_location you would check dwarf_whatform() of the
attribute to see if it is a simple constant or a location expression
block/ptr.
Suggested-by: Mark Wielaard <mjw@redhat.com>
Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When dwarf_lowpc failed we were not initializing ->size, so garbage was
being left there and thing like 'pfunct --sizes' were producing
senseless results.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In the same fashion as DW_TAG_volatile_type, as we need to get to the
DW_TAG_base_type at the end of the chain.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If it is C++ add DW_TAG_member entries to cu->tags_table and at
imported_declaration__fprintf fallback to cu__tag() if cu__function()
fails.
The right thing tho, long term, is to have a class for
"DW_TAG_imported_declaration" to register to what kind of tag this
points, if for DW_TAG_subprogram or to DW_TAG_member, the info is in the
DWARF DW_AT_import attribute, but so far we're not decoding it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If conf_load.extra_dbg_info is false don't call those functions, that
way we reduce the number of page faults by not accessing the DWARF
sections that contains these informations.
Together with the previous optimization (don't delete everything on
exit), this shaves off 10% of a C++ test case (libgklayout.so)!
Thanks to 'perf record -g + perf report -c fractal' for telling me this
:-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Next we'll add a new kind of tag, DW_TAG_perf_counter, that will come
from perf.data generated by 'perf report'.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So far all of these tags had just an abstract origin, so we only needed
to print the function it pointed to, but we need to treat it as an
DW_TAG_subprogram... fix it later, after 1.8, for now just dive in and
collect the types.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Sharing the same space with abstract_origin, so that we can remove the last
Dwarf_Off in dwarf_fprintf.c.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can more early return if we can't process files for some supported
debugging format and as well release all resources allocated when dwarves__exit
is called.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There is still the problem of handing the strings table to the CTF encoder, but
that will be fixed another day.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Such as signed, etc. This is in preparation for using directly ctf_strings.
Instead of duplicating it in the global strings table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are more things that should be handled differently, such as function
names coming from the .strtab ELF section instead of from the global strings_t
table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Till all the tags were processed, as in DWARF we can have class_member types
being defined _after_ them, so we don't find it when trying to recode
class_member at constructor time (class_member__new). Do it later after all the
types are hashed, in namespace__recode_dwarf_types.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We should do just as with typedefs, i.e. find the type these tags point to, and
create a new volatile/const tag pointing to the underlying bitfield tag.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For loaders to fill with the address of global variables.
More work is needed to cover relocation, registers, etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
CTF will need this distinction in that it handles functions differently, using
data in the ELF symbol table.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Because we already use ctf__load in libctf.c, rename the others to
disambiguate, and also as there are the __load_dir and __load_files
it looks more consistent.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Nasty trick, but works and should be properly documented in the sources
and here:
If struct namespace.shared_tags is 1, we actually are reusing the list
of enumerators in another namespace, so we shouldn't delete them, for
that list_for_each_tag now means more for each _unshared_ tag, so that
cu__delete doesn't visits it, double freeing enumerator tags.
type__for_each_enumerator knows that and only for enums we'll set this
->shared_tags bit to 1, so we should be safe...
Disgusting? send me a patch, but without increasing memory or processing
footprints, please ;-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
"pahole -Z foo" will create foo.SUNW_ctf, that if objcopy
--add-section'ed to the right word-sized object will work, sans VARARGS,
that will get fixed soon (as in, probably, tomorrow).
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I have to normalize this so that we don't have this special case, but
since we can have enum bitfields....
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Will later be used when generating the CTF info, be it in a separate
file, be it on a new ELF section inserted into this filename.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We now create a new integral type (enum or base_types), creating typedef
chains if needed, while caching the bit_size and bit_offset, so that we
can easily reencode the whole file into CTF.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This will help us in the next csets when we need to know both the full
size of the base_type used in an bitfield _and_ the size in bits of the
bitfield member.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Because we will need the "bit_offset" and "bit_size" names when converting the
representation of offset and size everywhere to be in bits, not bytes.
At the same time we will keep bitfield_size and bitfield_offset when we convert
from DWARF to CTF and will calculate them when loading CTF, so that the
conversion of the algorithms in dwarves_reorganize, that have all sorts of
subtle issues, can be left for later.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Amazing how many crept up over time, should have set the
execute bit of .git/hooks/pre-commit already, duh.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we immensely reduce the memory footprint by doing filtering and
other processing/pretty printing as the cus are loaded, discarding them
right away.
The next cset will use this scheme in pahole.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Also introducing cus__load, that load just one file.
The new cus__load_files routine now iterates thru the provided array
calling cus__load for each, and that in turn will try first dwarf__load,
and if that fail, i.e. if no DWARF info is found, call ctf__load.
This now allows loading DWARF _and_ CTF files at the same time. This
will be useful in the future when we, from DWARF generate CTF and at the
same time do a codiff, comparing the freshly generated CTF file with the
DWARF it came from.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Not used anymore now that cus__loadfl is sanitized. Now we can even
remove the fl (historically comes from libdwfl, when we used to pass an
argp, argh!).
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo