To take advantage of cache effects and to avoid calling cu__find_holes
more than once on the same struct.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
parameter__type was needed because the abstract_origin resolution was
done later, now it is at dwarf recode time, and for debugging formats
that don't have this crap, never. So it now can use the same idiom as
other tags: foo->tag.type.
parameter__name still exists because the tools still want a string
returned, but for some what they want is indeed the string_t, so that
when looking for a particular string it can be done as an string__find
for the key + integer comparision instead of doing a costlier strcmp.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Had to be a big sweeping change, but the regression tests shows just
improvements :-)
Now we stop using an id in struct tag, only storing the type, that now
uses 16 bits only, as CTF does.
Each format loader has to go on adding the types to the core, that
figures out if it is a tag that can be on the tag->type field
(tag__is_tag_type).
Formats that already have the types separated and in sequence, such as
CTF, just ask the core to insert in the types_table directly with its
original ID.
For DWARF, we ask the core to put it on the table, in sequence, and return the
index, that is then stashed with the DWARF specific info (original id, type,
decl_line, etc) and hashed by the original id. Later we recode everything,
looking up via the original type, getting the small_id to put on the tag->type.
The underlying debugging info not needed by the core is stashed in tag->priv,
and the DWARF loader now just allocates sizeof(struct dwarf_tag) at the end of
the core tag and points it there, and makes that info available thru
cu->orig_info. In the future we can ask, when loading a cu, that this info be
trown away, so that we reduce the memory footprint for big multi-cu files such
as the Linux kernel.
There is also a routine to ask for inserting a NULL, as we still have
bugs in the CTF decoding and thus some entries are being lost, to avoid
using an undefined pointer when traversing the types_table the ctf
loader puts a NULL there via cu__table_nullify_type_entry() and then
cu__for_each_type skips those.
There is some more cleanups for leftovers that I avoided cleaning to
reduce this changeset.
And also while doing this I saw that enums can appear without any
enumerators and that an array with DW_TAG_GNU_vector is actually a
different tag, encoded this way till we get to DWARF4 ;-)
So now we don't have to lookup on a hash table looking for DWARF
offsets, we can do the more sensible thing of just indexing the
types_tags array.
Now to do some cleanups and try to get the per cu encoder done. Then
order all the cus per number of type entries, pick the one with more,
then go on merging/recoding the types of the others and putting the
parent linkage in place.
Just to show the extent of the changes:
$ codiff /tmp/libdwarves.so.1.0.0 build/libdwarves.so.1.0.0
/home/acme/git/pahole/dwarves.c:
struct cu | -4048
struct tag | -32
struct ptr_to_member_type | -32
struct namespace | -32
struct type | -32
struct class | -32
struct base_type | -32
struct array_type | -32
struct class_member | -32
struct lexblock | -32
struct ftype | -32
struct function | -64
struct parameter | -32
struct variable | -32
struct inline_expansion | -32
struct label | -32
struct enumerator | -32
17 structs changed
tag__follow_typedef | +3
tag__fprintf_decl_info | +25
array_type__fprintf | +6
type__name | -126
type__find_first_biggest_size_base_type_member | -3
typedef__fprintf | +16
imported_declaration__fprintf | +6
imported_module__fprintf | +3
cu__new | +26
cu__delete | +26
hashtags__hash | -65
hash_64 | -124
hlist_add_head | -78
hashtags__find | -157
cu__hash | -80
cu__add_tag | +20
tag__prefix | -3
cu__find_tag_by_id | -2
cu__find_type_by_id | -3
cu__find_first_typedef_of_type | +38
cu__find_base_type_by_name | +68
cu__find_base_type_by_name_and_size | +72
cu__find_struct_by_name | +59
cus__find_struct_by_name | +8
cus__find_tag_by_id | +5
cus__find_cu_by_name | -6
lexblock__find_tag_by_id | -173
cu__find_variable_by_id | -197
list__find_tag_by_id | -308
cu__find_parameter_by_id | -60
tag__ptr_name | +6
tag__name | +15
variable__type | +13
variable__name | +7
class_member__size | +6
parameter__name | -119
tag__parameter | -14
parameter__type | -143
type__fprintf | -29
union__fprintf | +6
class__add_vtable_entry | -9
type__add_member | -6
type__clone_members | -3
enumeration__add | -6
function__name | -156
ftype__has_parm_of_type | -39
class__find_holes | -27
class__has_hole_ge | -3
type__nr_members_of_type | +3
lexblock__account_inline_expansions | +3
cu__account_inline_expansions | -18
ftype__fprintf_parms | +46
function__tag_fprintf | +24
lexblock__fprintf | -6
ftype__fprintf | +3
function__fprintf_stats | -18
function__size | -6
class__vtable_fprintf | -11
class__fprintf | -21
tag__fprintf | -35
60 functions changed, 513 bytes added, 2054 bytes removed, diff: -1541
/home/acme/git/pahole/ctf_loader.c:
struct ctf_short_type | +0
14 structs changed
type__init | -14
type__new | -9
class__new | -12
create_new_base_type | -7
create_new_base_type_float | -7
create_new_array | -8
create_new_subroutine_type | -9
create_full_members | -18
create_short_members | -18
create_new_class | +1
create_new_union | +1
create_new_enumeration | -19
create_new_forward_decl | -2
create_new_typedef | +3
create_new_tag | -5
load_types | +16
class__fixup_ctf_bitfields | -3
17 functions changed, 21 bytes added, 131 bytes removed, diff: -110
/home/acme/git/pahole/dwarf_loader.c:
17 structs changed
zalloc | -56
tag__init | +3
array_type__new | +20
type__init | -24
class_member__new | +46
inline_expansion__new | +12
class__new | +81
lexblock__init | +19
function__new | +43
die__create_new_array | +20
die__create_new_parameter | +4
die__create_new_label | +4
die__create_new_subroutine_type | +113
die__create_new_enumeration | -21
die__process_class | +79
die__process_namespace | +76
die__create_new_inline_expansion | +4
die__process_function | +147
__die__process_tag | +34
die__process_unit | +56
die__process | +90
21 functions changed, 851 bytes added, 101 bytes removed, diff: +750
/home/acme/git/pahole/dwarves.c:
struct ptr_table | +16
struct cu_orig_info | +32
2 structs changed
tag__decl_line | +68
tag__decl_file | +70
tag__orig_id | +71
ptr_table__init | +46
ptr_table__exit | +37
ptr_table__add | +183
ptr_table__add_with_id | +165
ptr_table__entry | +64
cu__table_add_tag | +171
cu__table_nullify_type_entry | +38
10 functions changed, 913 bytes added, diff: +913
/home/acme/git/pahole/ctf_loader.c:
2 structs changed
tag__alloc | +52
1 function changed, 52 bytes added, diff: +52
/home/acme/git/pahole/dwarf_loader.c:
struct dwarf_tag | +48
struct dwarf_cu | +4104
4 structs changed
dwarf_cu__init | +83
hashtags__hash | +61
hash_64 | +124
hlist_add_head | +78
hashtags__find | +161
cu__hash | +95
tag__is_tag_type | +171
tag__is_type | +85
tag__is_union | +28
tag__is_struct | +57
tag__is_typedef | +28
tag__is_enumeration | +28
dwarf_cu__find_tag_by_id | +56
dwarf_cu__find_type_by_id | +63
tag__alloc | +114
__tag__print_type_not_found | +108
namespace__recode_dwarf_types | +346
tag__namespace | +14
tag__has_namespace | +86
tag__is_namespace | +28
type__recode_dwarf_specification | +182
tag__type | +14
__tag__print_abstract_origin_not_found | +105
ftype__recode_dwarf_types | +322
tag__ftype | +14
tag__parameter | +14
lexblock__recode_dwarf_types | +736
tag__lexblock | +14
tag__label | +14
tag__recode_dwarf_type | +766
tag__ptr_to_member_type | +14
cu__recode_dwarf_types_table | +88
cu__recode_dwarf_types | +48
dwarf_tag__decl_file | +77
strings__ptr | +33
dwarf_tag__decl_line | +59
dwarf_tag__orig_id | +59
dwarf_tag__orig_type | +59
38 functions changed, 4432 bytes added, diff: +4432
build/libdwarves.so.1.0.0:
147 functions changed, 6782 bytes added, 2286 bytes removed, diff: +4496
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do nothing for now, just to reduce the size of the upcoming
type recoding patch, aka dwarves undwarvification.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Grrr, the previous commit has the other bits, and as I already pushed it
out publicly... <BROWN PAPER BAG ALERT!> here goes the rests. So much
for bissectability. Sigh.
But the regression test showed only one problem, in C++ code, that I'll
fix in the next commits.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can then decide in what hashtable we will add it, and this
also paves the way for a type array that will help us in reducing the
size of struct tag by removing the id field.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And comment the difference to tag__is_type:
tag__is_type == is this tag derived from the 'type' class?
tag__is_tag_type == is this tag a possible type for a tag, i.e.
one we will find in struct tag->type?
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Needed for CTF, where we can have many base types with name "unsigned",
but with different bit sizes, to implement bitfields.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now we just pass a NULL terminated array of filenames, since we got rid
of that ugly -e insertion hack.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And make the dwarves use it, so that we can remove duplicate strings in
a multi-CU file (vmlinux anyone?) and have it ready for insertion in a
compressed DWARF format with just the types, or better, CTF or some new
compressed debugging info format.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
Basically a wrapper for ftype__fprintf(&function__proto, ...) for the
cases we want the prototype rendered to a buffer, not to a file.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For correctly created and completely parsed debugging information the type will
always be found, but as we still need to parse more tags and expecting
debugging information to be always correctly built is not sane... sprinkle some
asserts.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is trying to get CTF friendly, where bitfields are not stored in the
equivalent to the DW_TAG_member dwarf TAG, but on "base types" with bit sizes
different than the real in the DWARF sense, base types (char, long, etc).
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In libdwarves.so well continue using DW_TAG_ entries and types for now, but its
becoming non-DWARF specific as will be demonstrated with the introduction of
ctf_loader.c in the upcoming csets.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Almost halves the time spent on processing a x86_64 vmlinux. Good, we
have features, now lets have performance ;-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
What a mouthful ;-) To be used in finding the most aligned member in a non-packed
type, i.e. one that originally wasn't __attribute__((packed)).
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>
Will just print the vtable as a comment on classes with vtables.
But we have to support multiple vtables when multiple inheritance exists.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Another C++ specific case:
- class TypeTemplate ByName(const string &, size_t);
+ class TypeTemplate ByName(const string &, size_t); /* linkage=_ZN4ROOT6Reflex12TypeTemplate6ByNameERKSsj */
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
And use it when expandind pointer types (using --expand_pointer).
This has to be done because the offset comments make no sense when expanding a
pointer.
Will be used as well in pahole --quiet.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
So that we can expand pointer types, useful for ABI signature checking. And to
fully browse a type, when using --expand_types is also of interest.
I have yet to disable printing the offsets when expanding pointers, where the
information is not useful at all, for now just ignore it, it gets back to a
sane state in the next field, after the pointer type expansion.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Arnaldo Carvalho de Melo
Arnaldo Carvalho de Melo