Eliminate rr::Precision

Reactor now only has full-precision implementations of transcendental
functions, so there's no need for a precision argument.

The only exceptions are the reciprocal function, and reciprocal square
root. Those are very useful to keep as part of the Reactor API because
there are fast approximate instructions for these operations. For now,
the precision is selected using a boolean parameter. This is intended to
later be replaced by having just an approximate intrinsic, and a query
Caps::rcpIsFast() which will allow users of Reactor to determine whether
to use 1/x or Rcp(). Specifically, when Rcp() is actually implemented as
1/x it would be wasteful to apply the Newton–Raphson method to obtain a
more precise result (cf. Caps::fmaIsFast() which addresses a similar
problem).

Bug: b/169755552
Change-Id: I553746aeee3ac01f6c47e06da17de1f6bfcd7df6
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/62289
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
11 files changed
tree: c29a058709eab2a5cf9a9472978e0e7859438cc1
  1. .vscode/
  2. build/
  3. build_overrides/
  4. docs/
  5. extensions/
  6. include/
  7. infra/
  8. src/
  9. tests/
  10. third_party/
  11. tools/
  12. .clang-format
  13. .dir-locals.el
  14. .gitignore
  15. .gitmodules
  16. Android.bp
  17. AUTHORS.txt
  18. BUILD.gn
  19. CMakeLists.txt
  20. CMakeSettings.json
  21. codereview.settings
  22. CONTRIBUTING.txt
  23. CONTRIBUTORS.txt
  24. DIR_METADATA
  25. LICENSE.txt
  26. OWNERS
  27. README.md
README.md

SwiftShader

License

Introduction

SwiftShader is a high-performance CPU-based implementation of the Vulkan graphics API12. Its goal is to provide hardware independence for advanced 3D graphics.

NOTE: SwiftShader's OpenGL ES implementation is no longer supported, and will be removed. The ANGLE project can be used to achieve a layered implementation of OpenGL ES (aka. “SwANGLE”).

Building

SwiftShader libraries can be built for Windows, Linux, and macOS.
Android and Chrome (OS) build environments are also supported.

  • CMake
    Install CMake for Linux, macOS, or Windows and use either the GUI or run the following terminal commands:

    cd build
    cmake ..
    cmake --build . --parallel
    
    ./vk-unittests
    

    Tip: Set the CMAKE_BUILD_PARALLEL_LEVEL environment variable to control the level of parallelism.

  • Visual Studio
    To build the Vulkan ICD library, use Visual Studio 2019 to open the project folder and wait for it to run CMake. Open the CMake Targets View in the Solution Explorer and select the vk_swiftshader project to build it.

Usage

The SwiftShader libraries act as drop-in replacements for graphics drivers.

On Windows, most applications can be made to use SwiftShader's DLLs by placing them in the same folder as the executable. On Linux, the LD_LIBRARY_PATH environment variable or -rpath linker option can be used to direct applications to search for shared libraries in the indicated directory first.

In general, Vulkan applications look for a shared library named vulkan-1.dll on Windows (vulkan-1.so on Linux). This ‘loader’ library then redirects API calls to the actual Installable Client Driver (ICD). SwiftShader's ICD is named libvk_swiftshader.dll, but it can be renamed to vulkan-1.dll to be loaded directly by the application. Alternatively, you can set the VK_ICD_FILENAMES environment variable to the path to vk_swiftshader_icd.json file that is generated under the build directory (e.g. .\SwiftShader\build\Windows\vk_swiftshader_icd.json). To learn more about how Vulkan loading works, read the official documentation here.

Contributing

See CONTRIBUTING.txt for important contributing requirements.

The canonical repository for SwiftShader is hosted at: https://swiftshader.googlesource.com/SwiftShader.

All changes must be reviewed and approved in the Gerrit review tool at: https://swiftshader-review.googlesource.com. You must sign in to this site with a Google Account before changes can be uploaded.

Next, authenticate your account here: https://swiftshader-review.googlesource.com/new-password (use the same e-mail address as the one configured as the Git commit author).

All changes require a Change-ID tag in the commit message. A commit hook may be used to add this tag automatically, and can be found at: https://gerrit-review.googlesource.com/tools/hooks/commit-msg. You can execute git clone https://swiftshader.googlesource.com/SwiftShader and manually place the commit hook in SwiftShader/.git/hooks/, or to clone the repository and install the commit hook in one go:

git clone https://swiftshader.googlesource.com/SwiftShader && (cd SwiftShader && git submodule update --init --recursive third_party/git-hooks && ./third_party/git-hooks/install_hooks.sh)

On Windows, this command line requires using the Git Bash Shell.

Changes are uploaded to Gerrit by executing:

git push origin HEAD:refs/for/master

When ready, add a project owner as a reviewer on your change.

Some tests will automatically be run against the change. Notably, presubmit.sh verifies the change has been formatted using clang-format 11.0.1. Most IDEs come with clang-format support, but may require upgrading/downgrading to the clang-format version 11.0.0 release version (notably Chromium's buildtools has a clang-format binary which can be an in-between revision which produces different formatting results).

Testing

SwiftShader's Vulkan implementation can be tested using the dEQP test suite.

See docs/dEQP.md for details.

Third-Party Dependencies

The third_party directory contains projects which originated outside of SwiftShader:

subzero contains a fork of the Subzero project. It originates from Google Chrome‘s (Portable) Native Client project. The fork was made using git-subtree to include all of Subzero’s history.

llvm-subzero contains a minimized set of LLVM dependencies of the Subzero project.

PowerVR_SDK contains a subset of the PowerVR Graphics Native SDK for running several sample applications.

googletest contains the Google Test project, as a Git submodule. It is used for running unit tests for Chromium, and Reactor unit tests. Run git submodule update --init to obtain/update the code. Any contributions should be made upstream.

Documentation

See docs/Index.md.

Contact

Public mailing list: swiftshader@googlegroups.com

General bug tracker: https://g.co/swiftshaderbugs
Chrome specific bugs: https://bugs.chromium.org/p/swiftshader

License

The SwiftShader project is licensed under the Apache License Version 2.0. You can find a copy of it in LICENSE.txt.

Files in the third_party folder are subject to their respective license.

Authors and Contributors

The legal authors for copyright purposes are listed in AUTHORS.txt.

CONTRIBUTORS.txt contains a list of names of individuals who have contributed to SwiftShader. If you‘re not on the list, but you’ve signed the Google CLA and have contributed more than a formatting change, feel free to request to be added.

Disclaimer

  1. Trademarks are the property of their respective owners.
  2. This is not an official Google product.