Replaces `std::shared_pointer` with `stx::atomic_ptr` and `stx::shared_ptr`.
Notes to programmers:
* This pr kills the use of `dynamic_cast`, `std::dynamic_pointer_cast` and `std::weak_ptr` on IDM objects, possible replacement is to save the object ID on the base object, then use idm::check/get_unlocked to the destination type via the saved ID which may be null. Null pointer check is how you can tell type mismatch (as dynamic cast) or object destruction (as weak_ptr locking).
* Double-inheritance on IDM objects should be used with care, `stx::shared_ptr` does not support constant-evaluated pointer offsetting to parent/child type.
* `idm::check/get_unlocked` can now be used anywhere.
Misc fixes:
* Fixes some segfaults with RPCN with interaction with IDM.
* Fix deadlocks in access violation handler due locking recursion.
* Fixes race condition in process exit-spawn on memory containers read.
* Fix bug that theoretically can prevent RPCS3 from booting - fix `id_manager::typeinfo` comparison to compare members instead of `memcmp` which can fail spuriously on padding bytes.
* Ensure all IDM inherited types of base, either has `id_base` or `id_type` defined locally, this allows to make getters such as `idm::get_unlocked<lv2_socket, lv2_socket_raw>()` which were broken before. (requires save-states invalidation)
* Removes broken operator[] overload of `stx::shared_ptr` and `stx::single_ptr` for non-array types.
* Fix typo in lv2_obj::create.
* Always save ipc_key as 0 for non-shared object creations, regardless of thbe value set by creation attribute.
* Show IPC key of shared memory (sys_mmapper) memory objects in kernel explorer.
* Remove custom event queue's IPC management of favour of universal LV2 approach.
* Move ipc_manager to FXO.
* Fix ipc_manager internal storage memory leak: deallocate entry when IPC object destroyed.
* Rewrite lv2_obj::create to be simpler (remove many duplicated code).
* Always execute lv2_obj::create under both IPC and IDM mutexes at once (not in non-atomic single-steps). Fixing potential case where concurrency can cause IDM to contain 2 or more different objects with the same IPC key with SYS_SYNC_NOT_CARE (instead of the same object).
* Do not rely on smart ptr reference count to tell if the object exists. Use similar approach as event queues as it makes error checkings accurate.
* Optimize lv2_event_port by using std::shared_ptr for queue which wasn't allowed before.
* Use atomic waitables instead instead of global thread wait as often as possible.
* Add ::is_stopped() and and ::is_paued() which can be used in atomic loops and with atomic wait. (constexpr cpu flags test functions)
* Fix notification bug of sys_spu_thread_group_exit/terminate. (old bug, enhanced by #9117)
* Function time statistics at Emu.Stop() restored. (instead of current "X syscall failed with 0x00000000 : 0")
- From RE, only protocols SYS_SYNC_FIFO and SYS_SYNC_PRIORITY are valid
- Use conditional atomic op store in a few places
- Properly revert changes in sys_event_flag_set when aomic op fails
