There are resources needed by the type system and other artifacts of
libabigail. Today, when the life time of those resources need to be
greater than all of artifacts of Abigail, then said resources are made
global.
But then global resources are not great, if anything because they
complicate the future use of the library in concurrent computing
setups.
As I was in the need to add one resource to be used by the type
system, I decided to sit down and first overhaul how these long lived
resources needed to be handled.
And here comes the concept of "environment". An environment is a
place where one can put resources that need to live longer than all
the other artifacts of the Abigail system. And so, the code that
creates Abigail artifacts needs and environment of for said artifacts
to use. In other words, artifacts now use an environment.
This has interesting and strong implications. We can only compare two
artifacts if they use the same environment. This is quite a strong
requirement.
But then when this requirement is fulfilled, comparing two types
amounts to just comparing two pointer values; hash values for types
can also be cached. Now *that* is great for speed of comparison, is
it not?
This patch introduce the concept environment (which is basically a new
abigail::ir::environment type), removes the global variables and uses
the environment instead. Each ABI artifact (either type or decl) now
has a ::get_environment() member function to get its environment.
This patch also disables the caching of hash values because the
caching must happen only *after* all types have been canonicalized.
We were not respecting that requirement until now, and that introduces
wrong hash values. A subsequent patch is going to re-introduce hash
value caching again, once the infrastructure is in place to set a flag
in the environment (hah!) once type canonicalization is done, and then
later read that flag when some client code requests a hash value, to
know if we should look in the hash value cache or not.
The patch obviously changes the output of numerous regression tests
(if anything b/c it disables hash value caching) so 'make check'
yields regressions. But then, it's only the subsequent patch that
updates the tests.
* include/abg-ir.h: Adjust note about memory management.
(class environment): Declare new class.
(translation_unit::translation_unit): Take an environment in
parameter.
(translation_unit::{g,s}et_environment): Declare new member
functions.
(type_or_decl_base::{g,s}et_environment): Likewise.
(type_or_decl_base::{get_cached_hash_value,
set_cached_hash_value}): Change the name of
decl_base::peek_hash_value() and decl_base::set_hash() here into
these and move them here.
(type_or_decl_base::hashing_started): Move
decl_base::hashing_started() here.
({g,s}et_environment_for_artifact): Declare new functions.
(class decl_base): Move member functions hashing_started(),
peek_hash_value() and set_hash() on to the type_or_decl_base base
class.
(scope_decl::scope_decl): Initialize the virtual member
type_or_decl_base().
(type_decl::{get_void_type_decl,
get_variadic_parameter_type_decl}): Remove these static member
functions. They are now non-static member functions of the new
environment type.
* src/abg-ir.cc (class environment_setter): New internal class.
(get_canonical_types_map): Remove. This now becomes a member
function of the environment type.
(class usage_watchdog): Remove.
(usage_watchdog_{s,w}ptr): Remove these typedefs.
(get_usage_watchdog_wptr, ref_usage_watchdog)
(maybe_cleanup_type_system_data): Remove these functions.
(translation_unit::priv::usage_watchdog_): Remove data member.
(translation_unit::priv::env_): New data member.
(translation_unit::priv::priv): Take an environment and initialize
the new env_ data member. Do not initialize the removed
usage_watchdog_.
(translation_unit::translation_unit): Take an environment
parameter.
(translation_unit::get_global_scope): Set the environment of a new
global scope.
(translation_unit::{g,s}et_environment): New accessors.
(translation_unit::bind_function_type_life_time): Set the
environment of the function type.
(struct environment::priv): New class.
(environment::{environment, ~environment, get_canonical_types_map,
get_variadic_parameter_type_decl, canonicalization_is_done}): New
member functions.
(struct type_or_decl_base::priv): New class.
(type_or_decl_base::{type_or_decl_base, hashing_started,
get_cached_hash_value, set_cached_hash_value, set_environment,
get_environment, traverse}): New member functions.
({s,g}get_environment_for_artifact): New functions.
(decl_base::priv::{hash_, hashing_started}): Remove.
(decl_base::priv::priv): Adjust.
(decl_base::decl_base): In the copy constructor, initialize the
virtual base type_or_decl_base. Do not initialize hash_ and
hashing_started data member that got removed.
(decl_base::{hashing_started, peek_hash_value, set_hash}): Remove
member functions.
(strip_typedef): Set the environment of the new type which has its
typedefs stripped off. Adjust the call to type_or_void().
(scope_decl::{add, insert}_member_decl): Set the environment of
the new member decl to the environment of its scope.
(synthesize_type_from_translation_unit)
(synthesize_function_type_from_translation_unit): Set the
environment for the newly synthesized type. Adjust calls to
type_or_void().
(type_or_void): Take an environment in parameter. Get the void
type from the environment.
(get_canonical_types_map): Remove.
(type_base::get_canonical_type_for): Get the canonical types map
from the environment, not from a global variable.
(type_decl::{get_void_type_decl,
get_variadic_parameter_type_decl}): Remove.
(pointer_type_def::pointer_type_def): Adjust call to type_or_void.
(reference_type_def::reference_type_def): Likewise.
(function_decl::parameter::get_pretty_representation): Get the
variadic parameter type decl from the environment.
(class_decl::priv::classes_being_compared_): Remove static data
member.
(class_decl::priv::{mark_as_being_compared,
unmark_as_being_compared, comparison_started): Use the "classes
being compared" map from the environment.
(class_decl::base_spec::get_hash): Adjust.
(keep_type_alive): Get the alive types array from the environment)
not from a global variable anymore.
(get_next_string): Put the counter in thread-local storage.
* src/abg-hash.cc (scope_decl::hash::operator())
(function_decl::hash::operator()): Do not handle caching (here).
* include/abg-corpus.h (corpus::{g,s}et_environment): Declare new
accessors.
* src/abg-corpus.cc (corpus::priv::env): New data member.
(corpus::priv::priv): Initialize it.
(corpus::corpus): Take an environment in parameter.
(corpus::{g,s}et_environment): Define new member functions
(corpus::add): Set the environment of the newly added translation
unit, if it's not set already set. In any case, assert that the
translation unit must use the same environment as the corpus.
* include/abg-dwarf-reader.h (create_read_context)
(read_corpus_from_elf): Take an environment parameter.
({s,g}et_debug_info_root_path, {s,g}et_environment): Declare new
functions.
* src/abg-dwarf-reader.cc (read_context::{env_,
offline_callbacks_}): New data members.
(read_context::read_context): Initialize them.
(read_context::clear_per_translation_unit_data): Do not touch the
void type declaration, it doesn't belong to the translation unit.
(read_context::{env, offline_callbacks}): New accessors.
(read_context::{create_default_dwfl}): New member function.
(read_context::dwfl_handle): Add a setter overload.
({s,g}et_debug_info_root_path): Define new accessors.
(create_default_dwfl, create_dwfl_sptr, create_default_dwfl_sptr):
Remove these.
(build_translation_unit_and_add_to_ir): Adjust to pass the
environment to the newly created translation unit.
(build_function_decl): Adjust to pass the environment to the
created function and parameter types. Get variadic parameter type
node from the current environment, not from a global variable.
And do not try to canonicalize function types here.
(read_debug_info_into_corpus): Set the environment of the newly
created corpus.
(build_ir_node_for_void_type): Get the void type node from the
current environment, rather than from a global variable.
(create_read_context): Take the environment in parameter.
Create the default dwarf front end library handle using the new
member function of the read context. Set the current environment
used by the reader.
(read_corpus_from_elf): Take an environment in
parameter. Overhaul. This is now simpler.
(has_alt_debug_info): Adjust the call to create_read_context() to
make it pass an empty environment.
* include/abg-fwd.h (class environment): Forward declare.
* include/abg-reader.h (read_translation_unit_from_file)
(read_translation_unit_from_buffer)
(read_translation_unit_from_istream)
(read_corpus_from_native_xml): Take an environment in parameter.
* src/abg-reader.cc (read_context::m_env): New data member.
(read_context::read_context): Initialize it.
(read_context::{get_environment, set_environment}): New data
member.
(read_translation_unit): Set environment of the new translation
unit.
(read_corpus_from_input): Set the environment of the new corpus.
(read_translation_unit_from_file)
(read_translation_unit_from_buffer)
(read_translation_unit_from_istream, read_corpus_from_native_xml):
Take an environment in parameter.
(build_function_parameter): Get variadic parameter type from the environment.
* src/abg-comparison.cc (compute_diff): Add asserts in all the
overloads to ensure that the artifact being compared come from the
same environment.
* tests/print-diff-tree.cc (main): Create an env for the ABI
artifacts to use.
* tests/test-abidiff.cc (main): Likewise.
* tests/test-diff-dwarf.cc (main): Likewise.
* tests/test-ir-walker.cc (main): Likewise.
* tests/test-read-dwarf.cc (main): Likewise.
* tests/test-read-write.cc (main): Likewise.
* tools/abicompat.cc (main): Likewise.
* tools/abidiff.cc (main): Likewise.
* tools/abidw.cc (main): Likewise.
* tools/abilint.cc (main): Likewise.
* tools/abipkgdiff.cc (main): Likewise.
git://sourceware.org / libabigail.git / commit