Every file the core touches goes through libretro-common's filestream,
path and dirent layers, taken from RetroArch: vfs_hybrid opens local
paths with libretro-common's own implementation and hands URI paths
(and, on Android, anything a local open cannot reach) to the
frontend's VFS. File::IOFile and File::DirectIOFile sit on RFILE, and
FileUtil, FileSearch and the directory walks on path_stat, path_mkdir
and retro_opendir. Dolphin's fopen, POSIX and Win32 file code,
std::filesystem and std::fstream are gone, with the dual VFS paths and
the core option that chose between them.
Files opened for reading alone are memory-mapped where the platform
can: reads copy straight out of the page cache, DirectIOFile's offset
reads on one mapped object are thread safe, and GetMappedPtr(), View()
and Prefetch() lend and warm without a copy. Text files are read a
line at a time through File::LineReader, lent from the mapping or a
window refilled a block at a time, never a byte at a time; JSON is
parsed straight from the mapping. Ini files and the cheat file are
built in memory and written once, an ini only when it changed and
then atomically.
The vendored rslc prints subgroup operations, so a device that runs them
in the pixel stage gets the subgroup header back: each subgroup reduces
its bounding box and one invocation writes it. Vulkan offers it where
the device has the basic, arithmetic, ballot and shuffle operations in
the fragment stage; Metal on Mac2 and Apple7 GPUs, whose
simd_is_helper_thread is probed at init for the inverted answer some AMD
drivers give. The driver bug that breaks the reduction with discard
still keeps it off.
Nothing ever made one: every backend was handed a null includer, and the
OpenGL backend's #include resolver returned the source untouched. The
parameter goes from CreateShaderFromSource and everything beneath it,
and ShaderCompileUtils with it.
The compute header comes back for the decoders, and compute shaders and
GPU texture decoding are reported as supported once more. The core
option still decides whether textures are decoded on the GPU.
Vendors rslc from RetroArch's libretro-common (gfx/shaders, built with
RSLC_EXTENDED) and has the Vulkan backend hand every vertex, geometry
and pixel stage to it for SPIR-V: no glslang on that path, no global
lock, any number of compiles in parallel. D3D and Metal still go
through glslang and SPIRV-Cross until rslc writes their code.
A stage rslc refuses is logged and written, with the error, to the
dump directory as bad_<stage>_Vulkan_<n>.txt.
rslc has no compute stage, storage buffers, atomics or subgroup
operations yet, so for now the backend does not offer what needs them:
GPU texture decoding (decoding stays on the CPU), the bounding box,
the dynamic vertex loader and the vertex-shader line and point
expansion (the geometry shader expands them).
While the NV extension is totally fine, the KHR extension should be able to support more hardware.
For NVIDIA, the hardware either supports both or neither, it just needs a driver from the last two years.
For AMD, the drivers from late 2022-12 seems to bring support for the KHR extension.
For Intel, the KHR is also supported for some years.
Fixes a crash that could occur if the static constructor function for
the MainSettings.cpp TU happened to run before the variables in
Common/Version.cpp are initialised. (This is known as the static
initialisation order fiasco.)
By using wrapper functions, those variables are now guaranteed to be
constructed on first use.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Now that we utilize C++17, we can simply return an optional containing
the code instead of using an out variable and a boolean result,
essentially combining them into one.
This provides a much more straightforward interface.
Greatly simplifies the overall interface when it comes to compiling
shaders. Also allows getting rid of a std::string overload of the same
name. Now std::string and const char* both go through the same function.
This reverts commit d23fd17e1a.
Dynamic sampler indexing is broken in VK_NV_glsl as of 385.41. The
performance gap doesn't seem to be as wide with the updated driver, so
to save maintaining two code paths, it's easier to just drop the
extension support completely.
LibretroAdmin