Same method that ldloc.s uses, which incorporates the byref test.

When we have the following sequence:

    ldloc n
    ldfld valuetype [Unity.Mathematics]Unity.Mathematics.int2 Foo::bar

and local n is a reference to value, when walking the instructions in
mono_method_to_ir, we generally try to avoid loading a whole value
type just to load one of the fields.  I believe this is an
optimization.

The test here is not quite complete, though, as we have ref valuetypes
where the object stored at the location is actually an address, in
which case we still need to treat it as we would a normal reference.

This optimization isn't present in the ldloc.n coded forms and is
written in a slightly more robust way in ldloc.s, so no changes are
necessary there.

As an alternative to this commit, we might adopt the ldloc.s test for
ldloc as well, or merge in
https://github.com/mono/mono/commit/29428d951637ff85b593ea5c9cc5d5236579906d/mono/mini/method-to-ir.c
from master which encapsulates much the same intent.

This brings us in line with GetDiskFreeSpaceExW on Windows as well as .NET Core.

Attempting to guard against MONO_HANDLE_IS_NULL performing a null deref while checking for null. Sourced from: https://github.com/mono/mono/pull/9188 blindfix for case 1232819

sets.

Making associated change to type_in_image to also check the constrained type for a match. Re-adding asserts now they they no longer trigger.

updating to K&R coding convention

Fixes https://github.com/mono/mono/issues/18127.

- Changed the behavior on debugger-agent, if we can't parse the new behavior is to return invalid_argument and not assert and stop debugging
- Changed the mono_domain_set_fast before return from assembly_commands.
- Add error message when return INVALID_ARGUMENT

Fixes #19146

Fixes #8915

This change modifies the `ConcurrentBag` implementation from corefx.
Since we cannot update the corefx submodule, make a copy of the
ConcurrentBag.cs file, fix the issue, and point the build at this copy.

The change is in the `TrySteal` method. It makes calls on the
`CDSCollectionETWBCLProvider`, which is removed by the manged linker
by default. Those calls should be wrapped in a
`CDSCollectionETWBCLProvider.Log.IsEnabled()` if block, so the linker
can understand to not make the calls.

There was a race where a domain was being unloaded while debugger would access it. A domain was only removed from the 'appdomains_list' as a very last step. The domain was already invalid to access at this point (locks freed for example).

Worse, images would be unloaded if only referenced by that domain. All places the debugger iterates domains hold the loader lock. The loader lock is acquired by the domain unloading process, so as long as a domain is not unloading when we access it inside of the loader lock we are safe.

Manually applied cherry-pick of https://github.com/mono/mono/pull/8428

Unity: Avoid allocation in Enum.HasFlags (case 1211643)

* [jit] Decompose some CEE_BOX opcodes later to allow more optimizations.

Optimize a code sequence emitted for Enum.HasFlag () by newer csc versions.
Also mark the temporary bblocks used by decompose_vtypes () as out-of-line if
the bblock under processing is out-of-line. Mark the domainvar as volatile to avoid
optimizing it away since references to it can now be generated later from the
decomposition of OP_BOX.

* [jit] Check that the enum types are the same.

* [jit] Fix support for generic enums.

* [jit] Disable the optimization with 64 bit enums on 32 bit platforms.

Fixes https://github.com/mono/mono/issues/17737.

* [debugger] Add locking around tls->frames usage/freeing

* [debugger] more locking and avoid race around mono_threads_join_lock & loader lock

This reverts commit edd8732e.

This updates the mono-build-tools-extra repo to revision:

9de3c42ef81ec4f79b53e7db32d390227d8c43c4

* [Debugger]  Debugger crashes when inside a class, there is an internal struct, with a field that is an enumerator.
files.myBucket.GetEnumerator().get_Current().Key
Fixes #10735

* [Debugger] Debugger crashes when there is a generic struct with a field that is an enumerator.
Example: files.get_Current().Key
A unit test that reproduces this crash was added too.
Fixes #10735

* Removing the extra space.

* UnityAlex cherry-pick modification: Removed tests

Fixes issue in mono_class_init where we would return immediately instead of jumping to the cleanup routine. This would leave init_list in a dirty state for subsequent calls leading to recursive type definitions being thrown incorrectly. (case 1191002)

Instead of cloning the mono-build-tools-extra and building the tools in
it, now get the binaries from Stevedore. These are only used on macOS
builds of Mono.

Fix a regression introduced by e05343dd: Disable the ldobj+stobj optimization
for reference types.

Fixes https://github.com/mono/mono/issues/6777.

Original commit https://github.com/Unity-Technologies/mono/commit/43d87f5b691b374211f4af35dbe51d1a2775ccee

Accidentally reverted https://github.com/Unity-Technologies/mono/commit/8d86df978f3907ccf038294b2730297c2b22fe20

Revert "Fix case 1044454: Stopwatch does not track time when an app is in the background or the device is asleep."

This reverts commit 442e9223.

Fix case 1044454: Stopwatch does not track time when an app is in the background or the device is asleep.