In 93da8e0abf, the page table construct
was moved to the common library (which utilized these inclusions). Since
the move, nothing requires these headers to be included within the
memory header.
- GPU will be released on shutdown, before pages are unmapped.
- On subsequent runs, current_page_table will be not nullptr, but GPU might not be valid yet.
When #2247 was created, thread_queue_list.h was the only user of
boost-related code, however #2252 moved the page table struct into
common, which makes use of Boost.ICL, so we need to add the dependency
to the common library's link interface again.
Given this is utilized by the loaders, this allows avoiding inclusion of
the kernel process definitions where avoidable.
This also keeps the loading format for all executable data separate from
the kernel objects.
Neither the NRO or NSO loaders actually make use of the functions or
members provided by the Linker interface, so we can just remove the
inheritance altogether.
This function passes in the desired main applet and library applet
volume levels. We can then just pass those values back within the
relevant volume getter functions, allowing us to unstub those as well.
The initial values for the library and main applet volumes differ. The
main applet volume is 0.25 by default, while the library applet volume
is initialized to 1.0 by default in the services themselves.
Modifying CMAKE_* related flags directly applies those changes to every
single CMake target. This includes even the targets we have in the
externals directory.
So, if we ever increased our warning levels, or enabled particular ones,
or enabled any other compilation setting, then this would apply to
externals as well, which is often not desirable.
This makes our compilation flag setup less error prone by only applying
our settings to our targets and leaving the externals alone entirely.
This also means we don't end up clobbering any provided flags on the
command line either, allowing users to specifically use the flags they
want.
We generally shouldn't be hijacking CMAKE_CXX_FLAGS, etc as a means to
append flags to the targets, since this adds the compilation flags to
everything, including our externals, which can result in weird issues
and makes the build hierarchy fragile.
Instead, we want to just apply these compilation flags to our targets,
and let those managing external libraries to properly specify their
compilation flags.
This also results in us not getting as many warnings, as we don't raise
the warning level on every external target.
We really don't need to pull in several headers of boost related
machinery just to perform the erase-remove idiom (particularly with
C++20 around the corner, which adds universal container std::erase and
std::erase_if, which we can just use instead).
With this, we don't need to link in anything boost-related into common.
Rather than make a global accessor for this sort of thing. We can make
it a part of the thread interface itself. This allows getting rid of a
hidden global accessor in the kernel code.
This condition was checking against the nominal thread priority, whereas
the kernel itself checks against the current priority instead. We were
also assigning the nominal priority, when we should be assigning
current_priority, which takes priority inheritance into account.
This can lead to the incorrect priority being assigned to a thread.
Given we recursively update the relevant threads, we don't need to go
through the whole mutex waiter list. This matches what the kernel does
as well (only accessing the first entry within the waiting list).
* gdbstub: fix IsMemoryBreak() returning false while connected to client
As a result, the only existing codepath for a memory watchpoint hit to break into GDB (InterpeterMainLoop, GDB_BP_CHECK, ARMul_State::RecordBreak) is finally taken,
which exposes incorrect logic* in both RecordBreak and ServeBreak.
* a blank BreakpointAddress structure is passed, which sets r15 (PC) to NULL
* gdbstub: DynCom: default-initialize two members/vars used in conditionals
* gdbstub: DynCom: don't record memory watchpoint hits via RecordBreak()
For now, instead check for GDBStub::IsMemoryBreak() in InterpreterMainLoop and ServeBreak.
Fixes PC being set to a stale/unhit breakpoint address (often zero) when a memory watchpoint (rwatch, watch, awatch) is handled in ServeBreak() and generates a GDB trap.
Reasons for removing a call to RecordBreak() for memory watchpoints:
* The``breakpoint_data`` we pass is typed Execute or None. It describes the predicted next code breakpoint hit relative to PC;
* GDBStub::IsMemoryBreak() returns true if a recent Read/Write operation hit a watchpoint. It doesn't specify which in return, nor does it trace it anywhere. Thus, the only data we could give RecordBreak() is a placeholder BreakpointAddress at offset NULL and type Access. I found the idea silly, compared to simply relying on GDBStub::IsMemoryBreak().
There is currently no measure in the code that remembers the addresses (and types) of any watchpoints that were hit by an instruction, in order to send them to GDB as "extended stop information."
I'm considering an implementation for this.
* gdbstub: Change an ASSERT to DEBUG_ASSERT
I have never seen the (Reg[15] == last_bkpt.address) assert fail in practice, even after several weeks of (locally) developping various branches around GDB. Only leave it inside Debug builds.
Makes it an instantiable class like it is in the actual kernel. This
will also allow removing reliance on global accessors in a following
change, now that we can encapsulate a reference to the system instance
in the class.
Within the kernel, shared memory and transfer memory facilities exist as
completely different kernel objects. They also have different validity
checking as well. Therefore, we shouldn't be treating the two as the
same kind of memory.
They also differ in terms of their behavioral aspect as well. Shared
memory is intended for sharing memory between processes, while transfer
memory is intended to be for transferring memory to other processes.
This breaks out the handling for transfer memory into its own class and
treats it as its own kernel object. This is also important when we
consider resource limits as well. Particularly because transfer memory
is limited by the resource limit value set for it.
While we currently don't handle resource limit testing against objects
yet (but we do allow setting them), this will make implementing that
behavior much easier in the future, as we don't need to distinguish
between shared memory and transfer memory allocations in the same place.
The previous code had some minor issues with it, really not a big deal,
but amending it is basically 'free', so I figured, "why not?".
With the standard container maps, when:
map[key] = thing;
is done, this can cause potentially undesirable behavior in certain
scenarios. In particular, if there's no value associated with the key,
then the map constructs a default initialized instance of the value
type.
In this case, since it's a std::shared_ptr (as a type alias) that is
the value type, this will construct a std::shared_pointer, and then
assign over it (with objects that are quite large, or actively heap
allocate this can be extremely undesirable).
We also make the function take the region by value, as we can avoid a
copy (and by extension with std::shared_ptr, a copy causes an atomic
reference count increment), in certain scenarios when ownership isn't a
concern (i.e. when ReserveGlobalRegion is called with an rvalue
reference, then no copy at all occurs). So, it's more-or-less a "free"
gain without many downsides.
With this, all kernel objects finally have all of their data members
behind an interface, making it nicer to reason about interactions with
other code (as external code no longer has the freedom to totally alter
internals and potentially messing up invariants).
After doing a little more reading up on the Opus codec, it turns out
that the multistream API that is part of libopus can handle regular
packets. Regular packets are just a degenerate case of multistream Opus
packets, and all that's necessary is to pass the number of streams as 1
and provide a basic channel mapping, then everything works fine for
that case.
This allows us to get rid of the need to use both APIs in the future
when implementing multistream variants in a follow-up PR, greatly
simplifying the code that needs to be written.
Previously this was required, as BitField wasn't trivially copyable.
BitField has since been made trivially copyable, so now this isn't
required anymore.
Relocates the error code to where it's most related, similar to how all
the other error codes are. Previously we were including a non-generic
error in the main result code header.
These can just be passed regularly, now that we use fmt instead of our
old logging system.
While we're at it, make the parameters to MakeFunctionString
std::string_views.
Instead of holding a reference that will get invalidated by
dma_pushbuffer.pop(), hold it as a copy. This doesn't have any
performance cost since CommandListHeader is 8 bytes long.
There's no real need to use a shared lifetime here, since we don't
actually expose them to anything else. This is also kind of an
unnecessary use of the heap given the objects themselves are so small;
small enough, in fact that changing over to optionals actually reduces
the overall size of the HLERequestContext struct (818 bytes to 808
bytes).
Now that we have the address arbiter extracted to its own class, we can
fix an innaccuracy with the kernel. Said inaccuracy being that there
isn't only one address arbiter. Each process instance contains its own
AddressArbiter instance in the actual kernel.
This fixes that and gets rid of another long-standing issue that could
arise when attempting to create more than one process.
Similar to how WaitForAddress was isolated to its own function, we can
also move the necessary conditional checking into the address arbiter
class itself, allowing us to hide the implementation details of it from
public use.
Rather than let the service call itself work out which function is the
proper one to call, we can make that a behavior of the arbiter itself,
so we don't need to directly expose those implementation details.
This makes the class much more flexible and doesn't make performing
copies with classes that contain a bitfield member a pain.
Given BitField instances are only intended to be used within unions, the
fact the full storage value would be copied isn't a big concern (only
sizeof(union_type) would be copied anyways).
While we're at it, provide defaulted move constructors for consistency.
Because of the recent separation of GPU functionality into sync/async
variants, we need to mark the destructor virtual to provide proper
destruction behavior, given we use the base class within the System
class.
Prior to this, it was undefined behavior whether or not the destructor
in the derived classes would ever execute.
This will be utilized by more than just that class in the future. This
also renames it from OpusHeader to OpusPacketHeader to be more specific
about what kind of header it is.
We already have the thread instance that was created under the current
process, so we can just pass the handle table of it along to retrieve
the owner of the mutex.
Removes a few unnecessary dependencies on core-related machinery, such
as the core.h and memory.h, which reduces the amount of rebuilding
necessary if those files change.
This also uncovered some indirect dependencies within other source
files. This also fixes those.
Places all error codes in an easily includable header.
This also corrects the unsupported error code (I accidentally used the
hex value when I meant to use the decimal one).
Places all of the functions for address arbiter operation into a class.
This will be necessary for future deglobalizing efforts related to both
the memory and system itself.
Removes a few inclusion dependencies from the headers or replaces
existing ones with ones that don't indirectly include the required
headers.
This allows removing an inclusion of core/memory.h, meaning that if the
memory header is ever changed in the future, it won't result in
rebuilding the entirety of the HLE services (as the IPC headers are used
quite ubiquitously throughout the HLE service implementations).
Avoids directly relying on the global system instance and instead makes
an arbitrary system instance an explicit dependency on construction.
This also allows removing dependencies on some global accessor functions
as well.
Given we already pass in a reference to the kernel that the shared
memory instance is created under, we can just use that to check the
current process, rather than using the global accessor functions.
This allows removing direct dependency on the system instance entirely.
In these cases the system object is nearby, and in the other, the
long-form of accessing the telemetry instance is already used, so we can
get rid of the use of the global accessor.
We already pass a reference to the system object to the constructor of the renderer,
so we can just use that instead of using the global accessor functions.
Reduces the potential amount of rebuilding necessary if any headers
change. In particular, we were including a header from the core library
when we don't even link the core library to the web_service library, so
this also gets rid of an indirect dependency.
Moves local global state into the Impl class itself and initializes it
at the creation of the instance instead of in the function.
This makes it nicer for weakly-ordered architectures, given the
CreateEntry() class won't need to have atomic loads executed for each
individual call to the CreateEntry class.
Any SDL invocation can call the even callback on the same thread, which can call GetSDLJoystickBySDLID and eventually cause double lock on joystick_map_mutex. To avoid this, lock guard should be placed as closer as possible to the object accessing code, so that any SDL invocation is with the mutex unlocked
Changes the interface as well to remove any unique methods that
frontends needed to call such as StartJoystickEventHandler by
conditionally starting the polling thread only if the frontend hasn't
started it already. Additionally, moves all global state into a single
SDLState class in order to guarantee that the destructors are called in
the proper order
MSVC does not seem to like using constexpr values in a lambda that were declared outside of it.
Previously on MSVC build the hotkeys to inc-/decrease the speed limit were not working correctly because in the lambda the SPEED_LIMIT_STEP had garbage values.
After googling around a bit I found: https://github.com/codeplaysoftware/computecpp-sdk/issues/95 which seems to be a similar issue.
Trying the suggested fix to make the variable static constexpr also fixes the bug here.
The comment already invalidates itself: neither MMIO nor rasterizer cache belongsHLE kernel state. This mutex has a too large scope if MMIO or cache is included, which is prone to dead lock when multiple thread acquires these resource at the same time. If necessary, each MMIO component or rasterizer should have their own lock.
This currently has the same behavior as the regular
OpenAudioRenderer API function, so we can just move the code within
OpenAudioRenderer to an internal function that both service functions
call.
This service function appears to do nothing noteworthy on the switch.
All it does at the moment is either return an error code or abort the
system. Given we obviously don't want to kill the system, we just opt
for always returning the error code.
Provides names for previously unknown entries (aside from the two u8
that appear to be padding bytes, and a single word that also appears
to be reserved or padding).
This will be useful in subsequent changes when unstubbing behavior related
to the audio renderer services.
This function is also supposed to check its given policy type with the
permission of the service itself. This implements the necessary
machinery to unstub these functions.
Policy::User seems to just be basic access (which is probably why vi:u
is restricted to that policy), while the other policy seems to be for
extended abilities regarding which displays can be managed and queried,
so this is assumed to be for a background compositor (which I've named,
appropriately, Policy::Compositor).
There's no real reason this shouldn't be allowed, given some values sent
via a request can be signed. This also makes it less annoying to work
with popping enum values, given an enum class with no type specifier
will work out of the box now.
It's also kind of an oversight to allow popping s64 values, but nothing
else.
This didn't really provide much benefit here, especially since the
subsequent change requires that the behavior for each service's
GetDisplayService differs in a minor detail.
This also arguably makes the services nicer to read, since it gets rid
of an indirection in the class hierarchy.
The kernel allows restricting the total size of the handle table through
the process capability descriptors. Until now, this functionality wasn't
hooked up. With this, the process handle tables become properly restricted.
In the case of metadata-less executables, the handle table will assume
the maximum size is requested, preserving the behavior that existed
before these changes.
This manages two kinds of streaming buffers: one for unified memory
models and one for dedicated GPUs. The first one skips the copy from the
staging buffer to the real buffer, since it creates an unified buffer.
This implementation waits for all fences to finish their operation
before "invalidating". This is suboptimal since it should allocate
another buffer or start searching from the beginning. There is room for
improvement here.
This could also handle AMD's "pinned" memory (a heap with 256 MiB) that
seems to be designed for buffer streaming.
The scheduler abstracts command buffer and fence management with an
interface that's able to do OpenGL-like operations on Vulkan command
buffers.
It returns by value a command buffer and fence that have to be used for
subsequent operations until Flush or Finish is executed, after that the
current execution context (the pair of command buffers and fences) gets
invalidated a new one must be fetched. Thankfully validation layers will
quickly detect if this is skipped throwing an error due to modifications
to a sent command buffer.
The NVFlinger service is already passed into services that need to
guarantee its lifetime, so the BufferQueue instances will already live
as long as they're needed. Making them std::shared_ptr instances in this
case is unnecessary.
Like the previous changes made to the Display struct, this prepares the
Layer struct for changes to its interface. Given Layer will be given
more invariants in the future, we convert it into a class to better
signify that.
With the display and layer structures relocated to the vi service, we
can begin giving these a proper interface before beginning to properly
support the display types.
This converts the display struct into a class and provides it with the
necessary functions to preserve behavior within the NVFlinger class.
* Fixes Unicode Key File Directories
Adds code so that when loading a file it converts to UTF16 first, to
ensure the files can be opened. Code borrowed from FileUtil::Exists.
* Update src/core/crypto/key_manager.cpp
Co-Authored-By: Jungorend <Jungorend@users.noreply.github.com>
* Update src/core/crypto/key_manager.cpp
Co-Authored-By: Jungorend <Jungorend@users.noreply.github.com>
* Using FileUtil instead to be cleaner.
* Update src/core/crypto/key_manager.cpp
Co-Authored-By: Jungorend <Jungorend@users.noreply.github.com>
These are more closely related to the vi service as opposed to the
intermediary nvflinger.
This also places them in their relevant subfolder, as future changes to
these will likely result in subclassing to represent various displays
and services, as they're done within the service itself on hardware.
The reasoning for prefixing the display and layer source files is to
avoid potential clashing if two files with the same name are compiled
(e.g. if 'display.cpp/.h' or 'layer.cpp/.h' is added to another service
at any point), which MSVC will actually warn against. This prevents that
case from occurring.
This also presently coverts the std::array introduced within
f45c25aaba back to a std::vector to allow
the forward declaration of the Display type. Forward declaring a type
within a std::vector is allowed since the introduction of N4510
(http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4510.html) by
Zhihao Yuan.
As fetching command list headers and and the list of command headers is a fixed 1:1 relation now, they can be implemented within a single call.
This cleans up the Step() logic quite a bit.
Fetching every u32 from memory leads to a big overhead. So let's fetch all of them as a block if possible.
This reduces the Memory::* calls by the dma_pusher by a factor of 10.
A fairly trivial change. Other sections of the codebase use nested
namespaces instead of separate namespaces here. This one must have just
been overlooked.
Gets rid of the largest set of mutable global state within the core.
This also paves a way for eliminating usages of GetInstance() on the
System class as a follow-up.
Note that no behavioral changes have been made, and this simply extracts
the functionality into a class. This also has the benefit of making
dependencies on the core timing functionality explicit within the
relevant interfaces.
Previously, we were completely ignoring for screenshots whether the game uses RGB or sRGB.
This resulted in screenshot colors that looked off for some titles.
There are some potential edge cases where gl_state may fail to track the
state if a related state changes while the toggle is disabled or it
didn't change. This addresses that.
Handles a pool of resources protected by fences. Manages resource
overflow allocating more resources.
This class is intended to be used through inheritance.
Fences take ownership of objects, protecting them from GPU-side or
driver-side concurrent access. They must be commited from the resource
manager. Their usage flow is: commit the fence from the resource
manager, protect resources with it and use them, send the fence to an
execution queue and Wait for it if needed and then call Release. Used
resources will automatically be signaled when they are free to be
reused.
Makes it consistent with the regular standard containers in terms of
size representation. This also gets rid of dependence on our own
type aliases, removing the need for an include.
The necessity of this parameter is dubious at best, and in 2019 probably
offers completely negligible savings as opposed to just leaving this
enabled. This removes it and simplifies the overall interface.
VKDevice contains all the data required to manage and initialize a
physical device. Its intention is to be passed across Vulkan objects to
query device-specific data (for example the logical device and the
dispatch loader).
We already store a reference to the system instance that the renderer is
created with, so we don't need to refer to the system instance via
Core::System::GetInstance()
This file is intended to be included instead of vulkan/vulkan.hpp. It
includes declarations of unique handlers using a dynamic dispatcher
instead of a static one (which would require linking to a Vulkan
library).
Places all of the timing-related functionality under the existing Core
namespace to keep things consistent, rather than having the timing
utilities sitting in its own completely separate namespace.
When I originally added the compute assert I used the wrong
documentation. This addresses that.
The dispatch register was tested with homebrew against hardware and is
triggered by some games (e.g. Super Mario Odyssey). What exactly is
missing to get a valid program bound by this engine requires more
investigation.
This was originally included because texture operations returned a vec4.
These operations now return a single float and the F4 prefix doesn't
mean anything.
Previous code relied on GLSL parameter order (something that's always
ill-formed on an IR design). This approach passes spatial coordiantes
through operation nodes and array and depth compare values in the the
texture metadata. It still contains an "extra" vector containing generic
nodes for bias and component index (for example) which is still a bit
ill-formed but it should be better than the previous approach.
i965 (and probably all mesa drivers) require GL_PROGRAM_SEPARABLE when using
glProgramBinary. This is probably required by the standard but it's ignored by
permisive proprietary drivers.
This commit it automatically generated by command in zsh:
sed -i -- 's/BitField<\(.*\)_le>/BitField<\1>/g' **/*(D.)
BitField is now aware to endianness and default to little endian. It expects a value representation type without storage specification for its template parameter.
This is compromise for swap type being used in union. A union has deleted default constructor if it has at least one variant member with non-trivial default constructor, and no variant member of T has a default member initializer. In the use case of Bitfield, all variant members will be the swap type on endianness mismatch, which would all have non-trivial default constructor if default value is specified, and non of them can have member initializer
Converts many of the Find* functions to return a std::optional<T> as
opposed to returning the raw return values directly. This allows
removing a few assertions and handles error cases like the service
itself does.
Some games search conditionally use global memory instructions. This
allows the heuristic to search inside conditional nodes for the source
constant buffer.
Some games call LDG at the top of a basic block, making the tracking
heuristic to fail. This commit lets the heuristic the decoded nodes as a
whole instead of per basic blocks.
This may lead to some false positives but allows it the heuristic to
track cases it previously couldn't.
A holdover from citra, the Horizon kernel on the switch has no
prominent kernel object that functions as a timer. At least not
to the degree of sophistication that this class provided.
As such, this can be removed entirely. This class also wasn't used at
all in any meaningful way within the core, so this was just code sitting
around doing nothing. This also allows removing a few things from the
main KernelCore class that allows it to use slightly less resources
overall (though very minor and not anything really noticeable).
No inheritors of the WaitObject class actually make use of their own
implementations of these functions, so they can be made non-virtual.
It's also kind of sketchy to allow overriding how the threads get added
to the list anyways, given the kernel itself on the actual hardware
doesn't seem to customize based off this.
This was previously causing:
warning C4828: The file contains a character starting at offset 0xa33
that is illegal in the current source character set (codepage 65001).
warnings on Windows when compiling yuzu.
This functions almost identically to DecodeInterleavedWithPerfOld,
however this function also has the ability to reset the decoder context.
This is documented as a potentially desirable thing in the libopus
manual in some circumstances as it says for the OPUS_RESET_STATE ctl:
"This should be called when switching streams in order to prevent the
back to back decoding from giving different result from one at a time
decoding."
Constant buffer values on the shader IR were using different offsets if
the access direct or indirect. cbuf34 has a non-multiplied offset while
cbuf36 does. On shader decoding this commit multiplies it by four on
cbuf34 queries.
* Implemented the puller semaphore operations.
* Nit: Fix 2 style issues
* Nit: Add Break to default case.
* Fix style.
* Update for comments. Added ReferenceCount method
* Forgot to remove GpuSmaphoreAddress union.
* Fix the clang-format issues.
* More clang formatting.
* two more white spaces for the Clang formatting.
* Move puller members into the regs union
* Updated to use Memory::WriteBlock instead of Memory::Write*
* Fix clang style issues
* White space clang error
* Removing unused funcitons and other pr comment
* Removing unused funcitons and other pr comment
* More union magic for setting regs value.
* union magic refcnt as well
* Remove local var
* Set up the regs and regs_assert_positions up properly
* Fix clang error
Cubemaps are considered layered and to create a texture view the texture
mustn't be a layered texture, resulting in cubemaps being bound as
cubemap arrays. To fix this issue this commit introduces an extra
surface parameter called "is_array" and uses this to query for texture
view creation.
Now that texture views for cubemaps are actually being created, this
also fixes the number of layers created for the texture view (since they
have to be 6 to create a texture view of cubemaps).
Some games (like Xenoblade Chronicles 2) clear both depth and stencil
buffers while there's a depth-only texture attached (e.g. D16 Unorm).
This commit reads the zeta format of the bound surface on
ConfigureFramebuffers and returns if depth and/or stencil attachments
were set. This is ignored on DrawArrays but on Clear it's used to just
clear those attachments, bypassing an OpenGL error.
In addition to the default, external, EDID, and internal displays,
there's also a null display provided as well, which as the name
suggests, does nothing but discard all commands given to it. This is
provided for completeness.
Opening a display isn't really a thing to warn about. It's an expected
thing, so this can be a debug log. This also alters the string to
indicate the display name better.
Opening "Default" display reads a little nicer compared to Opening
display Default.
This quite literally functions as a basic setter. No other error
checking or anything (since there's nothing to really check against).
With this, it completes the pm:bm interface in terms of functionality.
This appears to be a vestigial API function that's only kept around for
compatibility's sake, given the function only returns a success error
code and exits.
Since that's the case, we can remove the stubbed notification from the
log, since doing nothing is technically the correct behavior in this
case.
std::moveing a local variable in a return statement has the potential to
prevent copy elision from occurring, so this can just be converted into
a regular return.
Looking into the implementation of the C++ standard facilities that seem
to be within all modules, it appears that they use 7 as a break reason
to indicate an uncaught C++ exception.
This was primarily found via the third last function called within
Horizon's equivalent of libcxxabi's demangling_terminate_handler(),
which passes the value 0x80000007 to svcBreak.
According to documentation, if the argument of std::exp is zero, one is returned.
However we want the return value to be also zero in this case so no audio is played.
Commercial games assume that this value is 1 but they never set it. On
the other hand nouveau manually sets this register. On
ConfigureFramebuffers we were asserting for what we are actually
implementing (according to envytools).
With the loading screen merged, we don't want to actually show at this
point, but it still needs to be shown to actually create the context.
Turns out you can just show and hide it immediately and it'll work.
With shader caches on the horizon, one requirement is to provide visible
feedback for the progress. The shader cache reportedly takes several
minutes to load for large caches that were invalidated, and as such we
should provide a loading screen with progress.
Adds a loading screen widget that will be shown until the first frame of
the game is swapped. This was chosen in case shader caches are not being
used, several games still take more than a few seconds to launch and
could benefit from a loading screen.