commit | 1bbcf27097276ee362918137d4dafeed2e798627 | [log] [tgz] |
---|---|---|
author | Yilong Li <liyl@google.com> | Wed Dec 29 13:33:14 2021 -0800 |
committer | Yilong Li <liyl@google.com> | Wed Dec 29 23:29:30 2021 +0000 |
tree | 396f46a75bd424f8351bdaeb3326d8286e3ccaab | |
parent | cf1c04aad64d1d883f9810e2112e38bced032af8 [diff] | |
parent | c9706bdda0ac22b9856f1aa8261e5b9e15cd20c5 [diff] |
Merge tag 'sdk-1.2.198.0' into HEAD This updates glslang to 1.2.198. Bug: 90846 Change-Id: I8a446330eacc0cf1e6bd17ca1bcd70433d91bd92
Visual Studio 2013 is no longer supported
As scheduled, Microsoft Visual Studio 2013 is no longer officially supported.
Please upgrade to at least Visual Studio 2015.
The versioning scheme is being improved, and you might notice some differences. This is currently WIP, but will be coming soon. See, for example, PR #2277.
If you get a new compilation error due to a missing header, it might be caused by this planned removal:
SPIRV Folder, 1-May, 2020. Glslang, when installed through CMake, will install a SPIRV
folder into ${CMAKE_INSTALL_INCLUDEDIR}
. This SPIRV
folder is being moved to glslang/SPIRV
. During the transition the SPIRV
folder will be installed into both locations. The old install of SPIRV/
will be removed as a CMake install target no sooner than May 1, 2020. See issue #1964.
If people are only using this location to get spirv.hpp, I recommend they get that from SPIRV-Headers instead.
There are several components:
An OpenGL GLSL and OpenGL|ES GLSL (ESSL) front-end for reference validation and translation of GLSL/ESSL into an internal abstract syntax tree (AST).
Status: Virtually complete, with results carrying similar weight as the specifications.
An HLSL front-end for translation of an approximation of HLSL to glslang's AST form.
Status: Partially complete. Semantics are not reference quality and input is not validated. This is in contrast to the DXC project, which receives a much larger investment and attempts to have definitive/reference-level semantics.
See issue 362 and issue 701 for current status.
Translates glslang's AST to the Khronos-specified SPIR-V intermediate language.
Status: Virtually complete.
An API for getting reflection information from the AST, reflection types/variables/etc. from the HLL source (not the SPIR-V).
Status: There is a large amount of functionality present, but no specification/goal to measure completeness against. It is accurate for the input HLL and AST, but only approximate for what would later be emitted for SPIR-V.
glslangValidator
is command-line tool for accessing the functionality above.
Status: Complete.
Tasks waiting to be done are documented as GitHub issues.
Also see the Khronos landing page for glslang as a reference front end:
https://www.khronos.org/opengles/sdk/tools/Reference-Compiler/
The above page, while not kept up to date, includes additional information regarding glslang as a reference validator.
To use the standalone binary form, execute glslangValidator
, and it will print a usage statement. Basic operation is to give it a file containing a shader, and it will print out warnings/errors and optionally an AST.
The applied stage-specific rules are based on the file extension:
.vert
for a vertex shader.tesc
for a tessellation control shader.tese
for a tessellation evaluation shader.geom
for a geometry shader.frag
for a fragment shader.comp
for a compute shaderThere is also a non-shader extension
.conf
for a configuration file of limits, see usage statement for exampleInstead of building manually, you can also download the binaries for your platform directly from the master-tot release on GitHub. Those binaries are automatically uploaded by the buildbots after successful testing and they always reflect the current top of the tree of the master branch.
The following steps assume a Bash shell. On Windows, that could be the Git Bash shell or some other shell of your choosing.
cd <parent of where you want glslang to be> git clone https://github.com/KhronosGroup/glslang.git
cd <the directory glslang was cloned to, "External" will be a subdirectory> git clone https://github.com/google/googletest.git External/googletest
TEMPORARY NOTICE: additionally perform the following to avoid a current breakage in googletest:
cd External/googletest git checkout 0c400f67fcf305869c5fb113dd296eca266c9725 cd ../..
If you wish to assure that SPIR-V generated from HLSL is legal for Vulkan, wish to invoke -Os to reduce SPIR-V size from HLSL or GLSL, or wish to run the integrated test suite, install spirv-tools with this:
./update_glslang_sources.py
Assume the source directory is $SOURCE_DIR
and the build directory is $BUILD_DIR
. First ensure the build directory exists, then navigate to it:
mkdir -p $BUILD_DIR cd $BUILD_DIR
For building on Linux:
cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX="$(pwd)/install" $SOURCE_DIR # "Release" (for CMAKE_BUILD_TYPE) could also be "Debug" or "RelWithDebInfo"
For building on Android:
cmake $SOURCE_DIR -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX="$(pwd)/install" -DANDROID_ABI=arm64-v8a -DCMAKE_BUILD_TYPE=Release -DANDROID_STL=c++_static -DANDROID_PLATFORM=android-24 -DCMAKE_SYSTEM_NAME=Android -DANDROID_TOOLCHAIN=clang -DANDROID_ARM_MODE=arm -DCMAKE_MAKE_PROGRAM=$ANDROID_NDK_ROOT/prebuilt/linux-x86_64/bin/make -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK_ROOT/build/cmake/android.toolchain.cmake # If on Windows will be -DCMAKE_MAKE_PROGRAM=%ANDROID_NDK_ROOT%\prebuilt\windows-x86_64\bin\make.exe # -G is needed for building on Windows # -DANDROID_ABI can also be armeabi-v7a for 32 bit
For building on Windows:
cmake $SOURCE_DIR -DCMAKE_INSTALL_PREFIX="$(pwd)/install" # The CMAKE_INSTALL_PREFIX part is for testing (explained later).
The CMake GUI also works for Windows (version 3.4.1 tested).
Also, consider using git config --global core.fileMode false
(or with --local
) on Windows to prevent the addition of execution permission on files.
# for Linux: make -j4 install # for Windows: cmake --build . --config Release --target install # "Release" (for --config) could also be "Debug", "MinSizeRel", or "RelWithDebInfo"
If using MSVC, after running CMake to configure, use the Configuration Manager to check the INSTALL
project.
glslang can also be built with the GN build system.
depot_tools
Download depot_tools.zip, extract to a directory, and add this directory to your PATH
.
This only needs to be done once after updating glslang
.
With the current directory set to your glslang
checkout, type:
./update_glslang_sources.py gclient sync --gclientfile=standalone.gclient gn gen out/Default
With the current directory set to your glslang
checkout, type:
cd out/Default ninja
The grammar in glslang/MachineIndependent/glslang.y
has to be recompiled with bison if it changes, the output files are committed to the repo to avoid every developer needing to have bison configured to compile the project when grammar changes are quite infrequent. For windows you can get binaries from GnuWin32.
The command to rebuild is:
m4 -P MachineIndependent/glslang.m4 > MachineIndependent/glslang.y bison --defines=MachineIndependent/glslang_tab.cpp.h -t MachineIndependent/glslang.y -o MachineIndependent/glslang_tab.cpp
The above commands are also available in the bash script in updateGrammar
, when executed from the glslang subdirectory of the glslang repository. With no arguments it builds the full grammar, and with a “web” argument, the web grammar subset (see more about the web subset in the next section).
Use the steps in Build Steps, with the following notes/exceptions:
emsdk
needs to be present in your executable search path, PATH for Bash-like environments:emcmake cmake
-DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF
.-DENABLE_HLSL=OFF
if HLSL is not needed.-DENABLE_GLSLANG_JS=ON
.-DENABLE_GLSLANG_WEBMIN=ON
(disables HLSL)updateGrammar web
from the glslang subdirectory (or if using your own scripts, m4
needs a -DGLSLANG_WEB
argument)-DENABLE_GLSLANG_WEBMIN_DEVEL=ON
brotli
to compress the .js and .wasm filesExample:
emcmake cmake -DCMAKE_BUILD_TYPE=Release -DENABLE_GLSLANG_JS=ON \ -DENABLE_HLSL=OFF -DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF ..
You can download and install glslang using the vcpkg dependency manager:
git clone https://github.com/Microsoft/vcpkg.git cd vcpkg ./bootstrap-vcpkg.sh ./vcpkg integrate install ./vcpkg install glslang
The glslang port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.
Right now, there are two test harnesses existing in glslang: one is Google Test, one is the runtests
script. The former runs unit tests and single-shader single-threaded integration tests, while the latter runs multiple-shader linking tests and multi-threaded tests.
The runtests
script requires compiled binaries to be installed into $BUILD_DIR/install
. Please make sure you have supplied the correct configuration to CMake (using -DCMAKE_INSTALL_PREFIX
) when building; otherwise, you may want to modify the path in the runtests
script.
Running Google Test-backed tests:
cd $BUILD_DIR # for Linux: ctest # for Windows: ctest -C {Debug|Release|RelWithDebInfo|MinSizeRel} # or, run the test binary directly # (which gives more fine-grained control like filtering): <dir-to-glslangtests-in-build-dir>/glslangtests
Running runtests
script-backed tests:
cd $SOURCE_DIR/Test && ./runtests
If some tests fail with validation errors, there may be a mismatch between the version of spirv-val
on the system and the version of glslang. In this case, it is necessary to run update_glslang_sources.py
. See “Check-Out External Projects” above for more details.
Test results should always be included with a pull request that modifies functionality.
If you are writing unit tests, please use the Google Test framework and place the tests under the gtests/
directory.
Integration tests are placed in the Test/
directory. It contains test input and a subdirectory baseResults/
that contains the expected results of the tests. Both the tests and baseResults/
are under source-code control.
Google Test runs those integration tests by reading the test input, compiling them, and then compare against the expected results in baseResults/
. The integration tests to run via Google Test is registered in various gtests/*.FromFile.cpp
source files. glslangtests
provides a command-line option --update-mode
, which, if supplied, will overwrite the golden files under the baseResults/
directory with real output from that invocation. For more information, please check gtests/
directory's README.
For the runtests
script, it will generate current results in the localResults/
directory and diff
them against the baseResults/
. When you want to update the tracked test results, they need to be copied from localResults/
to baseResults/
. This can be done by the bump
shell script.
You can add your own private list of tests, not tracked publicly, by using localtestlist
to list non-tracked tests. This is automatically read by runtests
and included in the diff
and bump
process.
Another piece of software can programmatically translate shaders to an AST using one of two different interfaces:
The main()
in StandAlone/StandAlone.cpp
shows examples using both styles.
This interface is in roughly the last 1/3 of ShaderLang.h
. It is in the glslang namespace and contains the following, here with suggested calls for generating SPIR-V:
const char* GetEsslVersionString(); const char* GetGlslVersionString(); bool InitializeProcess(); void FinalizeProcess(); class TShader setStrings(...); setEnvInput(EShSourceHlsl or EShSourceGlsl, stage, EShClientVulkan or EShClientOpenGL, 100); setEnvClient(EShClientVulkan or EShClientOpenGL, EShTargetVulkan_1_0 or EShTargetVulkan_1_1 or EShTargetOpenGL_450); setEnvTarget(EShTargetSpv, EShTargetSpv_1_0 or EShTargetSpv_1_3); bool parse(...); const char* getInfoLog(); class TProgram void addShader(...); bool link(...); const char* getInfoLog(); Reflection queries
For just validating (not generating code), substitute these calls:
setEnvInput(EShSourceHlsl or EShSourceGlsl, stage, EShClientNone, 0); setEnvClient(EShClientNone, 0); setEnvTarget(EShTargetNone, 0);
See ShaderLang.h
and the usage of it in StandAlone/StandAlone.cpp
for more details. There is a block comment giving more detail above the calls for setEnvInput, setEnvClient, and setEnvTarget
.
This interface is in roughly the first 2/3 of ShaderLang.h
, and referred to as the Sh*()
interface, as all the entry points start Sh
.
The Sh*()
interface takes a “compiler” call-back object, which it calls after building call back that is passed the AST and can then execute a back end on it.
The following is a simplified resulting run-time call stack:
ShCompile(shader, compiler) -> compiler(AST) -> <back end>
In practice, ShCompile()
takes shader strings, default version, and warning/error and other options for controlling compilation.
Initial lexical analysis is done by the preprocessor in MachineIndependent/Preprocessor
, and then refined by a GLSL scanner in MachineIndependent/Scan.cpp
. There is currently no use of flex.
Code is parsed using bison on MachineIndependent/glslang.y
with the aid of a symbol table and an AST. The symbol table is not passed on to the back-end; the intermediate representation stands on its own. The tree is built by the grammar productions, many of which are offloaded into ParseHelper.cpp
, and by Intermediate.cpp
.
The intermediate representation is very high-level, and represented as an in-memory tree. This serves to lose no information from the original program, and to have efficient transfer of the result from parsing to the back-end. In the AST, constants are propagated and folded, and a very small amount of dead code is eliminated.
To aid linking and reflection, the last top-level branch in the AST lists all global symbols.
The primary algorithm of the back-end compiler is to traverse the tree (high-level intermediate representation), and create an internal object code representation. There is an example of how to do this in MachineIndependent/intermOut.cpp
.
Reduction of the tree to a linear byte-code style low-level intermediate representation is likely a good way to generate fully optimized code.
There is currently some dead old-style linker-type code still lying around.
Memory pool: parsing uses types derived from C++ std
types, using a custom allocator that puts them in a memory pool. This makes allocation of individual container/contents just few cycles and deallocation free. This pool is popped after the AST is made and processed.
The use is simple: if you are going to call new
, there are three cases:
the object comes from the pool (its base class has the macro POOL_ALLOCATOR_NEW_DELETE
in it) and you do not have to call delete
it is a TString
, in which case call NewPoolTString()
, which gets it from the pool, and there is no corresponding delete
the object does not come from the pool, and you have to do normal C++ memory management of what you new
Features can be protected by version/extension/stage/profile: See the comment in glslang/MachineIndependent/Versions.cpp
.