The fast paths follow the pattern that we established for fast ARC:
Framework base classes can opt in by implementing a `+_TrivialAllocInit`
method.
This opt-in behaviour is inherited and is removed implicitly in any
subclass that implements alloc or init methods (alloc and init are
treated independently).
Compilers can emit calls to `objc_alloc(cls)` instead of `[cls alloc]`,
`objc_allocWithZone(cls)` instead of `[cls allocWithZone: NULL]`, and
`objc_alloc_init` instead of `[[cls alloc] init]`.
Direct methods don't require very much support in the runtime. Apple
reuses their fast path for `-self` (which is supported only in the Apple
fork of clang, not the upstream version) for a fast init. Given that
the first few fields of the runtime's class structure have been stable
for around 30 years, I'm happy moving the flags word (and the
initialised bit, in particular) into the public ABI. This lets us do a
fast-path check for whether a class is initialised in class methods and
call `objc_send_initialize` if it isn't. This function is now exposed
as part of the public ABI, it was there already and does the relevant
checks without invoking any of the message-sending machinery.
Fixes#165#169
* Add __GNUSTEP_MSGSEND__ definition
* Mark test as skipped if return code is 77
* Skip tests using objc_msgSend if not available
* ManyManySelectors: Skip objc_msgSend if not available
* Skip UnexpectedException test on ARM and AArch64
* Add UnexpectedException.m to list of unit tests
* Call manyArgs with objc_msgSend directly
* Conditionally include ntdll.dll
* Use text relocation instead of GOT
* Use FlushInstructionCache instead of clear_cache for arm64
* Load address in two stages (adrp, add)
* objc_msgSend.aarch64.S add comments
* Add seh directives
* Move .seh_proc into slow sloop section
* Comment out cfi directives
* Substitute raw .seh directives with macros
* Add documentation of SEH annotations
* Detect CPU Architecture with preprocessor
* Cleanup CMakeLists.txt
Co-authored-by: David Chisnall <davidchisnall@users.noreply.github.com>
* Remove line in objc_msgSend.aarch64.S
Co-authored-by: David Chisnall <davidchisnall@users.noreply.github.com>
* Change Test CMakeList to use ARCHITECTURE var
* Use existing clear cache macro
* Change _WIN64 to _WIN32 and reorder labels
* Remove macro and replace _WIN64 with _WIN32
* Remove argument from non-win32 macro
---------
Co-authored-by: David Chisnall <davidchisnall@users.noreply.github.com>
This adds a dependency on a version of CMake with support for Objective-C,
removing a number of hacks to make CMake work and introduces a few
modernisations:
- Options use CMake's `option` mechanism.
- A lot of things now use generator expressions, which should improve the
things like the multi-config Ninja generator.
- We no longer depend on hacks to build in CI.
At the same time, a few other things are simplified:
- There is no longer support for building without C++ support and we depend on
a C++ standard library, not just a runtime. This makes it possible to use
more C++ features inside the runtime.
- We no longer support clang-cl on Windows and instead require clang.exe.
- Support for the Boehm GC has been removed.
This test used to fail on Windows, because Clang's codegen and transformation haven't been in-line with the requirements of the WinEH backend in LLVM. The following changes implement the missing pieces and let the test to pass in both debug and release mode:
https://reviews.llvm.org/D128190 [WinEH] Apply funclet operand bundles to nounwind intrinsics that lower to function calls in the course of IR transforms
https://reviews.llvm.org/D134441 [ObjC][ARC] Fix target register for call expanded from CALL_RVMARKER on Windows
https://reviews.llvm.org/D137939 [CGObjC] Open cleanup scope before SaveAndRestore CurrentFuncletPad and push CatchRetScope early
https://reviews.llvm.org/D137944 [ObjC][ARC] Teach the OptimizeSequences step of ObjCARCOpts about WinEH funclet tokens
This originally came up as an issue with libc++abi support (#152), but is not specific to that ABI.
* Use the C++ runtime to check for uncaught C++ exceptions.
As discussed in #152, use the function defined in the Itanium C++ ABI to
check whether the thrown exception is the current caught C++ exception
and needs rethrowing via `__cxa_rethrow()`.
Co-authored-by: Niels Grewe <grewe@ocean-insights.com>
Co-authored-by: David Chisnall <gnustep@theravensnest.org>
* Add test for emptying autorelease pool
* Fix arc autorelease pool emptying when adding further references
When releasing a reference in the arc autorelease pool, it is
possible and anticipated that new references may added to the pool.
This fix addresses an edge case where releasing a reference in the
same pool page as the stop position can add more references which
cause the insertion of a new page and emptyPool() returns early
after emptying the new page.
The previous checks for a deallocating object with negative reference count did not work because:
1. the sign bit has to be recreated as was happening in objc_delete_weak_refs()
2. there was no distinction between a saturated count and a negative reference count
refcount_max now indicates when the refcount has saturated and should no longer be mutated.
An underflow to -1 still maps to refcount_mask, allowing us to detect when an object is supposed to be deallocated.
Neither objc_release_fast_no_destroy_np() nor objc_retain_fast_np() mutate the refcount when it is one of those values, so the comment in objc_delete_weak_refs() was adjusted.
The reworked wrapping of C++ exceptions meant that we were missing a
dereference of the result of __cxa_begin_catch.
Add a test that triggers this issue. It would have occurred in the
non-ARC version if we actually did anything with the exception, but
compiling it in ARC mode makes the compiler insert retain / autorelease
around the exception object to ensure that it remains live.
Setting these tests to use 3 processors is weird, but it means that in
CI (where we do 4 tests in parallel), we won't ever run more than one of
these at a time (though we can run any other one test at the same time
as these). This should fix the intermittent failure.
We now correctly handle ivars that overlap with the end of what the
compiler thinks is the start of the superclass and bitfields at the
start of a class.
When removing a hash entry that was in the cell assigned to its hash, we
would clear the first bit in the second maps. If this entry was a
secondary value with the same hash, then this value became unreachable.
This very rarely showed up for two reasons. First, most of the tables
are insert-only and so we never try to remove things from them. Second,
it requires a particular sequence of inserts. It occasionally caused
weak references to be susceptible to use after free.
This has no effect most of the time, but if the runtime is built with
llvm-cov support, then this will cause each test to emit a .profraw
file, which can be merged with:
$ llvm-profdata merge -sparse Test/*.profraw -o libobjc.profdata
This can then be used to generate coverage reports from the test suite
and find code paths that are not currently being tested.
Methods now include a selector and extended type encoding, rather than a
method name and lgacy type encoding. Older ones are auto-upgraded.
Expose the extended type encoding via a function that JavaScriptCore
expects to exist.
macOS ships with libc++abi, which doesn't provide the hooks required
for interop, so this was causing all of the tests to fail to link in
the Travis macOS test. We're now correctly detecting that it won't
work on macOS and disabling those tests.
Hugo Melder
David Chisnall
Frederik Carlier
Frederik Seiffert
Stefan Gränitz
Graham--M
David Chisnall
David Chisnall
Dustin Howett
David Chisnall
David Chisnall
David Lobron