Clang's static analyzer tought me something new today: 'copy' properties are
not automatically deallocated 😒:
monotouch-debug.m:237:1: warning: 'XamarinHttpConnection' lacks a 'dealloc' instance method but must release '_completion_handler' and others
@implementation XamarinHttpConnection
^
This warning:
shared.m:216:3: warning: Incorrect decrement of the reference count of an object that is not owned at this point by the caller
[pool release];
^~~~~~~~~~~~~~
is somewhat incorrect, because we're using NSAutoreleasePools in uncommon ways
(at the same time it's not entirely incorrect either, because we're not
following Apple's documentation about how to use NSAutoreleasePools).
Luckily calling [NSAutoreleasePool drain] is equivalent to [NSAutoreleasePool
release], so just replace the latter with the former to silence the warning,
since clang doesn't know those two are equivalent.
At the beginning of dawn, not long after the big bang, we used to vibrate the
phone if there was a problem when connecting to the debugger in the IDE, and
the number of times the phone vibrated indicated a certain error condition.
This innovative debugging technique was at some point replaced with more
intuitive (albeit less innovative) error reporting, however the *_connect_*
family of functions continued returning the number of times the phone should
vibrate, even if the caller was now soundlessly ignoring this information.
After many years someone had the wonderful idea of running a static analyzer
on the code, and now the unused return value is not so silent anymore:
monotouch-debug.m:663:5: warning: Value stored to 'rv' is never read
rv = monotouch_connect_usb ();
^ ~~~~~~~~~~~~~~~~~~~~~~~~
monotouch-debug.m:665:5: warning: Value stored to 'rv' is never read
rv = monotouch_connect_wifi (hosts);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
monotouch-debug.m:667:5: warning: Value stored to 'rv' is never read
rv = xamarin_connect_http (hosts);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
So fix the warning by removing the return value.
This fixes an issue clang's static analyzer found: if an exception occured in
a call to managed code, we wouldn't process the list of objects to dispose:
trampolines-invoke.m:549:2: warning: Potential leak of memory pointed to by 'dispose_list'
MONO_THREAD_DETACH; // COOP: This will switch to GC_SAFE
^~~~~~~~~~~~~~~~~~
./xamarin/runtime.h:306:11: note: expanded from macro 'MONO_THREAD_DETACH'
} while (0)
^
Fix this by always processing the list of objects to dispose, even if
exceptions occur.
trampolines.m:75:22: warning: Result of 'malloc' is converted to a pointer of type 'id', which is incompatible with sizeof operand type 'void *'
id *buf = (id *) malloc (sizeof (void *) * length);
~~~~ ^~~~~~ ~~~~~~~~~~~~~~~
trampolines-i386.m:126:19: warning: Assigned value is garbage or undefined
it->state->edx = v[1];
^ ~~~~
trampolines-x86_64.m:410:16: warning: Assigned value is garbage or undefined
*reg_ptr = v [stores];
^ ~~~~~~~~~~
trampolines-x86_64.m:447:14: warning: Assigned value is garbage or undefined
*reg_ptr = v [stores++];
^ ~~~~~~~~~~~~
Getting a time zone instance in two different code paths, one allocating the
time zone instance, and the other not allocating, is problematic when we're
unconditionally freeing the time zone at the end.
xamarin-support.m:58:2: warning: Incorrect decrement of the reference count of an object that is not owned at this point by the caller
[tz release];
^~~~~~~~~~~~
So fix this by autoreleasing the allocated timezone.
* [XM] Seperate parsing from compilation in AOT code
- Parsing command line options was too entangled with actually compiling
- Refactor test code to centralize Compile, reducing some complexity of tests
- Groundwork for hybrid vs non-hybrid AOT work
* Add hybrid/standard AOT support
* Add xammac_tests to makefile/jenkins
* Add flag to force AOT
* Disable MonoTouchFixtures.Contacts.ContactStoreTest.GetUnifiedContacts on XM due to prompts on Jenkins
Use @rpath instead of @executable_path in dylibs, since it allows us to be
more flexible when placing dylibs in the app.
In particular with this change it's trivial to put libmonosgen-2.0.dylib in
the container app, and reference it from extensions.
This is a series of fixes to the dynamic libraries we build / create to remove
any unnecessary bloat (unused architectures, bitcode).
A brand new watchOS app with no changes goes from 35MB to 11MB with these
fixes (with incremental builds disabled, the app size is 10MB).
--------------------------------------------------------------------------------
* [runtime] Split list of architectures into simulator and device-specific lists.
* [runtime] Build separate dylibs for device and simulator.
Build separate dylibs for device and simulator, since we already install these
into different locations.
This makes both the simulator and device builds slightly faster (since the
respective dylibs are smaller, and less data to copy around).
For watchOS apps, this saves ~430kb.
* [runtime] Strip bitcode from dylibs. Fixes#51352.
We know that dylibs will never be shipped to the App Store, so we'll never
need them to have bitcode.
So just strip the bitcode from all our dylibs, since this makes apps with
fastdev significantly smaller (and thus much faster to upload to watch
devices).
For watchOS apps this is a very significant improvement: a branch new watchOS
app without any changes goes from 35MB to 17MB.
https://bugzilla.xamarin.com/show_bug.cgi?id=51352
* [mtouch] Fix dylib compilation to not embed full bitcode.
Facts
=====
a. The output from the AOT compiler is an assembly (.s) file.
b. Clang's assembler does not support -fembed-bitcode-marker (only -fembed-
bitcode), so when we ask clang to -fembed-bitcode-marker, the assembler
receives a -fembed-bitcode argument.
c. This means that the assembled object file does not contain the
__LLVM/__bitcode and __LLVM/__cmdline sections (it does however contain an
__LLVM/__asm section).
d. The native linker will create a bitcode assembly section if none of the
object files passed to the linker contain a __LLVM/__bitcode section and
there's an __LLVM/__asm section present.
e. The end result is that when we build to a dylib, we end up (unexpectedly,
because we ask Clang to -fembed-bitcode-marker) including both armv7k and
bitcode in the dylib, thus bloating the dylib size significantly.
Solution
========
We manually add the __LLVM/__bitcode and __LLVM/__cmdline sections to the .s
file Mono's AOT compiler generated. This way the .o file will have the magic
sections, and the linker will not include bitcode (only the bitcode marker) in
the final library.
An empty watchOS extension with incremental builds is now 6MB smaller (down
to 11MB from 17MB).
The completion handler block must be copied to the XamarinHttpConnection
instance, otherwise we'll just store a pointer to a stack block, and once we
invoke the block we'll access stack memory (probably from another thread),
which is really not what we want to do.
https://bugzilla.xamarin.com/show_bug.cgi?id=44568
The length argument for `strncpy` specifies how many characters to copy, not
the length of the target string, which makes our usage incorrect.
Fix our usage, and use the `strlcpy` variant instead, which takes the length
of the target string.
And use `strlcat` instead of `strcat`.
Use metadata tokens instead of strings to find types and methods.
This makes the code to find methods more compact (a lot less strings in the
executable, and additionally in most cases a compact representation (32-bit
integer) of the corresponding metadata token and additional information can be
used, which results in less executable code (fewer parameters to methods,
etc)), resulting in smaller executables.
Size savings are around 200kb for dont link apps, and 20-60kb for linked apps
(this obviously varies a lot depending on how much has to registered by the
registrar).
| | Before | After | Diff |
|----------------|--------------:|--------------:|------------------:|
| dontlink/32bit | 102.810.144 | 102.609.456 | -200.688 = -0,20% |
| dontlink/64bit | 107.420.576 | 107.221.792 | -198.784 = -0,19% |
| linksdk/32bit | 40.957.296 | 40.936.864 | -20.432 = -0,05% |
| linksdk/64bit | 43.113.136 | 43.093.936 | -19.200 = -0,04% |
| linkall/32bit | 38.410.032 | 38.348.288 | -61.744 = -0,16% |
| linkall/64bit | 40.315.200 | 40.267.344 | -47.856 = -0,12% |
Additionally I've removed the `lazy_map` dictionary, which we populated at
startup and was used to map between Class instances and the corresponding
managed type's FullName, and instead iterate over a native array of Class ->
metadata token mappings whenever we need to look up the managed type for a
certain Class instance.
This is slightly slower for each type we need to look up (for a non-linked app
there might be a 2000-3000 entries in the native array, which would be
iterated instead of using a hashtable lookup), but it's only done once per
type and there's a significant startup memory improvement.
For a non-linked test app I get the following using the Xamarin profiler:
| | Before | After | Diff |
|-------------------|--------:|--------:|----------------:|
| Memory allocated | 2,8 MB | 2,4 MB | -0,4 MB = -14 % |
| Objects allocated | 43678 | 38463 | -5215 = -12 % |
| Private bytes | 26,6 MB | 24,4 MB | -2,2 MB = -8,3% |
| Working set | 26,6 MB | 24,4 MB | -2,2 MB = -8,3% |
Managed exception marshaling interferes with the debugger, because it adds
exception handlers to executing code, which makes the Mono runtime think an
exception is handled when logically it's not (although technically it is).
The consequence is that the IDEs will only be notified when we re-throw the
exception after catching it, making it impossible for the IDEs to stop when
the exception is thrown (they will instead stop when we re-throw the
exception).
So disable managed exception marshaling (unless the user changed the default
behavior) when a debugger is attached.
This is the same behavior as Xamarin.Android.
https://bugzilla.xamarin.com/show_bug.cgi?id=45116
Setting this option prints this to stdout:
> Mono Warning: option gen-compact-seq-points is deprecated.
and it's ignored, so just don't set this option.
Example code:
public override void ViewDidLoad ()
{
throw new Exception ("USELESS");
}
Current output with unhandled exceptions that are marshaled:
Unhandled Exception:
System.Exception: USELESS
at (wrapper managed-to-native) AppKit.NSApplication:NSApplicationMain (int,string[])
at AppKit.NSApplication.Main (System.String[] args) [0x00041] in /work/maccore/master/xamarin-macios/src/AppKit/NSApplication.cs:98
at UselessExceptions.MainClass.Main (System.String[] args) [0x00007] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/Main.cs:10
[ERROR] FATAL UNHANDLED EXCEPTION: UselessExceptions.CustomException: USELESS
at (wrapper managed-to-native) AppKit.NSApplication:NSApplicationMain (int,string[])
at AppKit.NSApplication.Main (System.String[] args) [0x00041] in /work/maccore/master/xamarin-macios/src/AppKit/NSApplication.cs:98
at UselessExceptions.MainClass.Main (System.String[] args) [0x00007] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/Main.cs:10
Note how the managed frame where the exception was thrown does not show up.
This is because we technically catch exceptions when marshaling them, and then
later we call mono_raise_exception to raise the same exception. Unfortunately
that leads to overwriting the initial stack trace, and we end up with a stack
trace that does not include the location where the original exception was
thrown.
So instead of calling mono_raise_exception to rethrow the same exception, we
use ExceptionDispatchInfo, which is able to capture the stack trace for both
the original exception and the new exception, producing the following output:
System.Exception: USELESS
at UselessExceptions.ViewController.ViewDidLoad () [0x0000c] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/ViewController.cs:27
--- End of stack trace from previous location where exception was thrown ---
at (wrapper managed-to-native) AppKit.NSApplication:NSApplicationMain (int,string[])
at AppKit.NSApplication.Main (System.String[] args) [0x00041] in /work/maccore/master/xamarin-macios/src/AppKit/NSApplication.cs:98
at UselessExceptions.MainClass.Main (System.String[] args) [0x00007] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/Main.cs:10
[ERROR] FATAL UNHANDLED EXCEPTION: UselessExceptions.CustomException: USELESS
at UselessExceptions.ViewController.ViewDidLoad () [0x0000c] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/ViewController.cs:27
--- End of stack trace from previous location where exception was thrown ---
at (wrapper managed-to-native) AppKit.NSApplication:NSApplicationMain (int,string[])
at AppKit.NSApplication.Main (System.String[] args) [0x00041] in /work/maccore/master/xamarin-macios/src/AppKit/NSApplication.cs:98
at UselessExceptions.MainClass.Main (System.String[] args) [0x00007] in /Users/rolf/Downloads/filed-bug-test-cases-master/Xamarin/bxc45742/Main.cs:10
Incidently this is how Xamarin.Android does it [1].
[1]: 9387f2fe16https://bugzilla.xamarin.com/show_bug.cgi?id=45742
* [tests] Remove Classic SDK tests.
* Remove XI/Classic support.
This also means we can remove support for the legacy registrars.
* [monotouch-test] Remove legacy registrar tests.
* [tests/mtouch] Remove Classic tests (and legacy registrar logic).
* [tests/scripted] Fix tests to reference Xamarin.iOS.dll.
At startup we send a request to all the IP addresses we have,
so we must make sure to not get confused if we get responses
from more than one of them.
This fix also requires an updated mlaunch.
https://bugzilla.xamarin.com/show_bug.cgi?id=44568
We've used the dynamic registrar for years now when selecting the IL registrar
(and I've never heard about anybody doing it), so just remove all the related
(and in fact dead) code.
* [runtime] Use printf on watchOS, NSLog doesn't shown up (by default).
* [runtime] Use a wrapper function for logging.
So that we can chose between printf and NSLog at runtime,
depending on where we're running.
The watchOS device has limited networking support; in particular
it does not allow inbound/output network connections using 'bind'
(kernel-level sandbox restrictions).
This means that we can't use BSD sockets to connect to the debugger
in the IDE on the desktop. Instead we create an http tunnel that
knows how to convert socket send/recv data into http requests on
both sides.
https://bugzilla.xamarin.com/show_bug.cgi?id=41554
Launching a watchOS extension on device with the managed debugger
attached is slow, which means that the launch watchdog will kick in
and kill the app before it has launched.
So we attach the native debugger as well, which prevents the launch
watchdog from killing the app. Incidentally it also makes watchOS
not background the app.
We're using private API to determine whether a native debugger is
attached, but it's only in debug code, and as such would not be
included in release builds for customer apps. Also the code is
currently limited to watchOS since it's not needed on other
platforms for now.
The watchOS device has limited networking support; in particular
it does not allow inbound/output network connections using 'bind'
(kernel-level sandbox restrictions).
This means that we can't use BSD sockets to connect to the debugger
in the IDE on the desktop. Instead we create an http tunnel that
knows how to convert socket send/recv data into http requests on
both sides.
https://bugzilla.xamarin.com/show_bug.cgi?id=41554
Launching a watchOS extension on device with the managed debugger
attached is slow, which means that the launch watchdog will kick in
and kill the app before it has launched.
So we attach the native debugger as well, which prevents the launch
watchdog from killing the app. Incidentally it also makes watchOS
not background the app.
We're using private API to determine whether a native debugger is
attached, but it's only in debug code, and as such would not be
included in release builds for customer apps. Also the code is
currently limited to watchOS since it's not needed on other
platforms for now.
64-bit iOS 9+ devices have a pagesize of 16kb (even when running 32-bit apps).
This means all executable code must have sectors aligned to 16kb when running
on such devices.
The native linker uses the min iOS version to determine the sector alignment;
if min iOS version is < 8.0, then the sector alignment is 4k, otherwise 16k.
This means that when we create our 32-bit dylibs we must link them with a min
iOS version of 8.0, or they won't work on a 64-bit device in a 32-bit app (bug
So change our makefiles to link armv7[s] dylibs with min iOS version 8.0.
[1] https://bugzilla.xamarin.com/show_bug.cgi?id=43102
Runtime
- Added support for Vector2d, Vector3d and Vector4d SIMD types
- Added support for GKBox, GKQuad and GKTriangle SIMD types
GameplayKit
- Apple introduced GKQuadTreeNode and GKQuadTree in Xcode 7.1 and
removed those types in a later Xcode (7.2?) but we kept them around.
Now apple introduced again both types but renamed them to GKQuadtreeNode
and GKQuadtree (lowercase t), this is a breaking change and since we do
care about binary compat we are just changing the registration name and
keeping the same managed name deprecating old methods and introducing
the new ones.
- Added tests for new SIMD types
Alex Soto
Rolf Bjarne Kvinge
Chris Hamons
Sebastien Pouliot
Sebastien Pouliot