Using `eB5G6R5UnormPack16` (with a swizzle for `R5G6B5Unorm`) removes the need for `VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT` when those formats are aliased which happens in Sonic Mania among other titles.
Adreno GPUs have significant performance penalties from usage of `VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT` which require disabling UBWC and on Turnip, forces linear tiling. As a result, it's been made an optional quirk which doesn't supply the flag in `VkImageCreateInfo` and logs a warning if a view with a different Vulkan format from the original image is created.
We often need to alias the underlying data as multiple Vulkan formats which requires the `eMutableFormat` bit to be set in `VkImageCreateInfo`, without doing this there'll be validation layer errors and potentially GPU bugs.
As we no longer set the layout to general inside the Texture constructor, yet, we need it to be set prior to the image being used as an attachment. We need to transition the layout to `eGeneral` after creation of the texture object.
We incorrectly determined an Adreno driver bug to require padding between binding slots but the real issue was not supporting consecutive binding writes for `VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER` and was fixed by the padding slot unintentionally requiring individual writes. The quirk has now been corrected to explicitly specify this as the bug and the solution is more apt.
Any lookups done using `GetAlignedRecursiveRange` incorrectly added intervals in the exclusive interval entry lookups as the condition for adding them was the reverse of what it should've been due to a last minute refactor, it led to graphical glitches and crashes. This has been fixed and the lookups should return the correct results.
On certain devices, accesses to a protected memory region can return `si_code` as non-`SEGV_ACCERR` values, this leads to a crash as we only pass access violations to the trap handler and would lead to not doing so on those devices which would then result in going to the crash handler.
A large amount of Texture/Buffer views would expire before reuse could occur in `Texture::GetView`/`Buffer::GetView`. These can lead to a substantial memory allocation given enough time and they are now deleted during the lookup while iterating on all entries.
It should be noted that there are a lot of duplicate views that don't live long enough to be reused and the ultimate solution here is to make those views live long enough to be reused.
Similar to constant redundant synchronization for textures, there is a lot of redundant synchronization of buffers. Albeit, buffer synchronization is far cheaper than texture synchronization it still has associated costs which have now been reduced by only synchronizing on access.
There was a lot of redundant synchronization of textures to and from host constantly as we were not aware of guest memory access, this has now been averted by tracking any memory accesses to the texture memory using the NCE Memory Trapping API and synchronizing only when required.
An API for trapping accesses to guest memory and performing callbacks based on those accesses alongside managing protection of the memory. This is a fundamental building block for avoiding redundant synchronization of resources from the guest and host.
Note: All accesses are treated as write accesses at the moment, support for picking up read accesses will be implemented later
An interval map is a crucial piece of infrastructure required for memory faulting to track any regions that have an associated callback and their protection. Additionally, efficient page-aligned lookups with semantics optimal for memory faulting are also a requirement and the ability to associate multiple regions with a single callback/protection entry rather than doing so on a per-region basis as we deal with split-mapping resources.
This is a prerequisite to memory trapping as we need to write to the mirror to avoid a race condition with external threads writing to a texture/buffer while we do so ourselves for the sync on a read/write, it also avoids an additional `mprotect` to `-WX`/`RWX` on a read access.
An additional advantage for textures especially is that we now support split-mapping textures due to laying them out in a contiguous mirror and they will not require costly algorithmic changes. Buffers should also benefit from not needing to iterate over every region when they are split into multiple mappings.
`CreateMirror` is limited to creating a mirror of a single contiguous region which does not work when creating a contiguous mirror of multiple non-contiguous regions. To support this functionality, `CreateMirrors` which expects a list of page-aligned regions and maps them into a contiguous mirror.
We want to create arbitrary mirrors in the guest address space and to make this possible, we map the entire address space as a shared memory file. A mirror is mapped by using `mmap` with the offset into the guest address space.
Previously for methods with count > 1 the subchannel and engine would be looked up for each part of the method rather than only doing so at the start. Each call also needed to be looked up to see if it touched a macro or GPFIFO method. Fix this by doing checks outside of the main dispatch loop with templated helper lambdas to avoid needing to repeat lots of code. Maxwell3D is the only subchannel with a fast path for now but more can be added later if needed.
Almost every Maxwell format now directly corresponds to a Vulkan format. This allows formats to be passed through and the swizzle used directly from guest (with some extra swizzle handling for edge cases) thus saving the need to explicitly support each swizzle combination which is adds a lot of code bloat. The format header is additionally reordered with line breaks to separate formats by their bits-per-block.
We always submit pipeline divisor descriptions regardless of binding input rate being vertex rather than instance. This is invalid behavior and has been fixed by only submitting binding descriptors when the input rate is per-instance.
Adreno proprietary drivers suffer from a bug where `VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER` requires 2 descriptor slots rather than one, we add a padding slot to fix this issue. `QuirkManager` was introduced to handle per-vendor/per-device errata and allow enabling this on Adreno proprietary drivers specifically as to not affect the performance of other devices.
Quirk terminology was deemed to be inappropriate for describing the features/extensions of a device. It has been replaced with traits which is far more fitting but quirks will be used as a terminology for errata in devices.
The texture handle offset calculation involved an incorrect shift by descriptor size which was found to be unnecessary and would result in an invalid handle that had the wrong TIC/TSC index and caused broken rendering.
`nodes` and `syncTextures` were cleared after waiting on the `CommandExecutor` fence rather than before, this wasted execution time after the wait for something that could be performed prior to the wait.
We now attempt to enable `VK_KHR_uniform_buffer_standard_layout` when present as lax UBO layout significantly reduces complexity. If a device doesn't support this extension, we still assume that the device supports it implicitly as this has proven to be true across all major mobile GPU vendors regardless of the driver version but enabling this prevents validation layer errors.
We depend on past commands to have completed execution in a renderpass, a subpass dependency on all graphics stages from `VK_SUBPASS_EXTERNAL` to subpass #0 is used to enforce this. Nvidia and Adreno proprietary drivers implicitly do this but Turnip or Mali drivers require this or they execute out of order.
Blocklinear texture decoding was broken for padding blocks and would incorrectly decode them resulting in major texture corruption for any textures with their widths not aligned to 64 bytes. This has now been fixed with neater code which avoids redundant repetition of any code using lambdas and functions where necessary.
Stencil operations are configurable to be the same for both sides or have independent stencil state for both sides. It is controlled via the previously unimplemented `stencilTwoSideEnable`.
Fermi2D supports macros in addition to Maxwell3D, these both share code memory. To support this we rework the macro interpreter to support passing in a target engine and abstract the communications out into an interface that can be implemented by applicable engines.
```
GPFIFO <-> MME <-> Maxwell3D
^ ^---> Fermi2D
X------------> I2M
X------------> MaxwellComputeB
X--Flush-----> MaxwellDMA
```
Shader programs allocate instructions and blocks within an `ObjectPool`, there was a global pool prior that was never reaped aside from on destruction. This led to a leak where the pool would contain resources from shader programs that had been deleted, to avert this the pools are now tied to shader programs.
