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% |
Right now the logic exists in a few places, both in and outside the
linker. We recently began to use part of the linker pipeline in normal /
all builds so it's easier to share (and unify) the code now.
The real gain is to avoid copying assemblies, in particular large ones,
more than strictly needed while building.
E.g. a build including a very large 1.3GB assembly, with several
native libraries embedded, save a lot of time avoiding the rewrites
mtouch (before)
Total time: 64202 ms
mtouch (after)
Total time: 34840 ms
* Add XM support for RemoveUserResourcesSubStep
* Tests supplied by @chamons
Run the partial static registrar separately for 32-bit and 64-bit, since this
is required with the upcoming changes to embed metadata tokens inside the
generated output, because the metadata tokens are different between the 32-bit
and 64-bit versions of Xamarin.iOS.dll.
Also make sure to properly resolve the 32-bit and 64-bit assemblies correctly
(by setting the ArchDirectory on the assembly resolver), so that we don't pick
up the reference assembly (which does not have the right metadata tokens).
Additionally stop running the partial static registrar for MonoTouch.Dialog-1,
since with the upcoming changes to use metadata tokens in the generated
output, we won't support registering anything more than once. This shouldn't
make much of an impact, because MonoTouch.Dialog-1 is fairly small, and
doesn't take long to register in the dynamic registrar. For device builds (or
when the static registrar is selected) this has no effect, since in that case
we're registering everythinga anyway.
Link the executable with LinkWith attributes' libraries in the simulator when
doing incremental builds, since we don't create dylibs there.
Fixes several mtouch test failures:
1) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_LinkAll(Unified)
2) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_LinkAll(TVOS)
3) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_LinkSDK(Unified)
4) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_LinkSDK(TVOS)
5) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_NoLink(Unified)
6) Test Failure : Xamarin.MTouch.FastDev_NoFastSim_NoLink(TVOS)
7) Test Failure : Xamarin.MTouch.FastDev_Sim(Unified)
8) Test Failure : Xamarin.MTouch.FastDev_Sim(TVOS)
Update mdb files even if the corresponding assembly didn't change, because the
mdb can change even if the assembly didn't (if whitespace was modified in the
source code, causing code lines to move).
https://bugzilla.xamarin.com/show_bug.cgi?id=39535
If the cache is invalid we print a warning:
> A full rebuild will be performed because the cache is either incomplete or entirely missing.
and set `Driver.Force = true;` (in Application.cs).
This later means that extracting the native code is done on each target:
```
public static bool IsUptodate (string source, string target)
{
if (Driver.Force)
return false;
```
even if this is identical between 32 and 64 bits (targets). That's
inefficient and, for large binding libraries (e.g. > 1GB), has a
noticable impact on build time (see timestamps).
Considering that the cache is cleaned (when detected as invalid) then
this Force condition is not really needed.
E.g. in `IsUptodate`
* the first time (arch) it's called will have to extract the native library;
* if a 2nd arch is built (fat) then it will be found as present and will
not be extracted again
Removing the `Driver.Force = true;` in this condition let the `-f` option
continue to extract it twice, which can be useful in debugging and testing.
As such the check is not removed from `IsUptodate`
Timestamps (before)
Setup: 25 ms
Resolve References: 1605 ms
Extracted native link info: 10465 ms
...
Timestamps (after)
Setup: 24 ms
Resolve References: 1560 ms
Extracted native link info: 5473 ms
...
Total build times (from XS) was around 90-100 seconds so 5 seconds is
about 10%. The actual savings will depend on how much native code needs
to be extracted, but it should help most release builds (almost always
fat builds).
* Comment is wrong: the code is never executed in parallel
* If reached then RemoveResources will be called and already check for
symbols (and load them when needed). Just a simplification (it won't
really save time as it's not loaded twice)
IIRC this used to be needed with a (rather old) version of Cecil.
The current code does nothing as the Load will only hit the cache
and not other properties are changed (compared to the old commented
code)
* [mtouch] Add missing HasParameters check inside linker and static registrar
Without the checks new, empty collections can be allocated and their
whole and only purpose will be to iterate up to 0 (nop).
The checks saves a small amount of memory (collections) and time.
* [registrar] Fix method comparison when they have no parameters
The SDK does not ship any, non-tool, .exe files. In fact .exe _should_
never need to be resolved since the main .exe is always given as an input
to mtouch.
Still it's possible (if quite uncommon) to refer to other .exe assemblies
just like if they were .dll. However those can only come from the
RootDirectory (and not the other places that ship with the SDK).
This "fix" ensure lookups for *.exe is done only inside the RootDirectory
location, speeding up (a bit) resolving assemblies.
Native libraries are already linked into the dylib for the binding assembly,
which means that if we also link it into the main executable, the native code
ends up twice in the app (which is bad for many reasons).
https://bugzilla.xamarin.com/show_bug.cgi?id=42473
The container app may not reference the same third-party frameworks as
extensions, which means that we must make sure the extension's frameworks are
also included in the app bundle.
So when building extensions save a list of all third-party frameworks, and
then read that list and include those frameworks when building the main app.
https://bugzilla.xamarin.com/show_bug.cgi?id=45800
This fixes the following mmptests:
1) Classic_NewRefCount_Warns (Xamarin.MMP.Tests.MMPTests.Classic_NewRefCount_Warns)
2) SystemMono_SmokeTest (Xamarin.MMP.Tests.MMPTests.SystemMono_SmokeTest)
That fails like this with earlier versions of Mono 4.8:
Undefined symbols for architecture i386:
"_mono_btls_x509_lookup_method_mono_init", referenced from:
-u command line option
"_mono_btls_x509_name_list_add", referenced from:
-u command line option
"_mono_btls_x509_name_list_free", referenced from:
-u command line option
"_mono_btls_x509_name_list_get_count", referenced from:
-u command line option
"_mono_btls_x509_name_list_get_item", referenced from:
-u command line option
"_mono_btls_x509_name_list_new", referenced from:
-u command line option
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)
error MM5109: Native linking failed with error code 1. Check build log for details.
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
* [AVFoundation] Add new constructor for AVAssetExportSession.
Add a new constructor that takes an enum instead of a string to have
a strong typed version of the default constructor to reduce possible
errors when passing a random string.
Fixes bug https://bugzilla.xamarin.com/show_bug.cgi?id=44443
* Use smart enums as requested in the PR review.
* Set manually the enum int values.
This makes it possible to set linker flags per assembly:
[assembly: LinkWith (LinkerFlags = "-lsqlite3")]
Which is required when incremental builds is enabled and a particular assembly
needs special linker flags (because we don't propagate the global -gcc_flags
to each dylib we build when doing incremental builds).
Also add an option to set the dlsym mode for an assembly (using the LinkWith
attribute).
Duration before: 1,60s
Duration after: 1,54s
Difference: -0,06s = -3,8%
Memory usage hardly changed (-21 kb of 540 MB), but the number of method calls
shrunk significantly.
Method calls before: 86.720.379
Method calls after: 74.390.061
Difference: -12.330.318 = -14,2%
The call to `GetSystemVoidType` was #2 on the list of method calls (whens
sorted by 'self'), called 1072 times taking 1429 ms each time. After this
change it's only called once (and obviously pushed way down the list).
- BuildAndLaunchTime is replacing AppLaunchTime as it calculates both
build time and launch time for different linker modes.
* [mtouch/tests] Add RegistrarTime test
- Also fix MTouchTool --registrar:dynamic
* [system-dependencies] Add support for installing Xcode's first-launch installs.
* [system-dependencies] Use the Archive Utility to extract Xcode xips.
Apple changed their format (again), so don't try to process the xip manually,
just invoke Apple's Archive Utility.
Another advantage is that the Archive Utility compresses the output (to about
half), saving multiple GB of hard disk space (from ~10 GB to ~5 GB).
* [system-dependencies] Add Xcode testing comment.
* [system-dependencies] Check if an Xcode package is in ~/Downloads, and if so use it.
This makes it easier to verify that provisioning works correctly whenever a new Xcode comes out.
Jeffrey Stedfast
Rolf Bjarne Kvinge
Sebastien Pouliot
Chris Hamons
Manuel de la Pena
Vincent Dondain
Sebastien Pouliot