Merge remote-tracking branch 'aosp/upstream-master' into update-shaderc

32d3ec31 Merge pull request #1394 from greg-lunarg/kg20
b0c42b28 Update spirv-tools known-good.
4f888534 Fix #1391: Remove use of nonportable strnlen().
b91189db Merge pull request #876 from ligfx/cmaketargetincludedirectories
a895f378 CMake: use target_include_directories to expose includes
92d05c0c Merge pull request #1386 from zeux/master
369dc87a Merge pull request #1387 from jeffbolznv/disassembly_explicit_types
fa34a9ad Merge pull request #1385 from KhronosGroup/fix-strtod
3e8e9f7b PP: Implement locale-independent strtod, using istringstream and a fast path.
af7a9487 Add bit width of types to disassembleInstruction
6c52f896 PP: Remove second parsing of numbers recorded in macros; save/use original.
1ea1b13f Testing: Add new tests, and new ways of testing, for floating-point.
8e4b496d Merge pull request #1388 from greg-lunarg/kg19
d2b55801 Update spirv-tools known-good
b239d22f Fix TextureUpgradeAndSamplerRemovalTransform when used with qualifiers
c6d25539 Merge pull request #1384 from LoopDawg/self-cast
c5991671 HLSL: allow self-type cast (as no-op passthrough)
2aaef122 Bump revision.
ebec9094 GLSL: Fix #1279: refract does not have a double-type eta.
a0044f4f Merge pull request #1381 from LoopDawg/coverage_array
98e1d7f6 Merge pull request #1383 from amdrexu/bugfix
b4a2a6cf Fix issue #1376: SPV_AMD_gpu_shader_half_float is not emitted under vulkan1.1
4e6d3eaf HLSL: require coverage mask to be arrayed output.
cfb05ec7 Merge pull request #1379 from LoopDawg/groupid-fix
91a8178e HLSL: various SPIR-V compute shader IDs must be a 3-vector of integers.
90de7a74 Merge pull request #1378 from LoopDawg/append-decl-order
1326b8c7 HLSL: Allow stream output Append() method after entry point.
1831087e SPV: Fix #1374: For an SSBO 16-bit access, only emit StorageUniformBufferBlock16 capability.
2fb966aa Merge pull request #1375 from Igalia/nroberts/aml-arrayio
ecbd056b Tests: Fix #1372: Don't legalize runtests HLSL tests.
22b71f9a Skip outermost array when assigning locations to auto-array interfaces
fd9d9ef4 Bump version.
d2e9829a Merge pull request #1370 from KhronosGroup/fix-param-types
115c3b14 Merge pull request #1369 from greg-lunarg/kg18
d3ed90be Fix #944: Convert argument type to match formal parameter type.
517eabb4 Update spirv-opt known-good
25bef930 Merge pull request #1363 from mattparks/patch4
115cf8ea Merge pull request #1368 from danginsburg/issue_1367
fb6924d2 Fix issue #1367 - change the I/O remapper to ignore push constants so it does not apply a binding/descriptor set to them.
9cf275bb Build: Add missing break statements. Fixes #1052.
1199cf92 Fixed install for SPIRV, glslang, and hlsl when building shared libs
e375dad6 Merge pull request #1364 from greg-lunarg/kg17
6b5d52a6 Update known-good.
46e07313 GLSL/Vulkan: Warn about arrays of arrays of resources that need bindings.
b4cb70fc GLSL: Fix #1359: don't allow unsized arrays as initializers.
d8462c6f validate script: fix path
c325f436 GLSL: Fix #1300: Can redeclare without size a sized built-in block array.
3beac945 Infrastructure: If using .hlsl suffix, default is -D.
4c574708 Bump revision.
2ead40ff Tests: Add usage and tests for previous commit.
fccbb8b4 Merge branch 'nicebyte-glsl-ext'
62f84fd5 Merge branch 'glsl-ext' of into nicebyte-glsl-ext
33ddaaaf Make FindLanguage use the entire name if parseStageName is false
ef203bfa Fix build error
3350741e Make glslang validator support files ending in .glsl

Change-Id: If6560ef79acf0ec03be97d26a5ababf31ad6d424
Testing: on Linux; unit tests on Windows
tree: 033cab25a8b77da247fc3e0ff761daee985466f4
  1. .appveyor.yml
  2. .clang-format
  3. .gitattributes
  4. .gitignore
  5. .travis.yml
  6. CMakeLists.txt
  7. ChooseMSVCCRT.cmake
  8. External/
  9. OGLCompilersDLL/
  10. README-spirv-remap.txt
  12. SPIRV/
  13. StandAlone/
  14. Test/
  15. glslang/
  16. gtests/
  17. hlsl/
  18. known_good.json
  19. known_good_khr.json
  20. make-revision

Also see the Khronos landing page for glslang as a reference front end:

The above page includes where to get binaries, and is kept up to date regarding the feature level of glslang.


Build Status Build status

An OpenGL and OpenGL ES shader front end and validator.

There are several components:

  1. A GLSL/ESSL front-end for reference validation and translation of GLSL/ESSL into an AST.

  2. An HLSL front-end for translation of a broad generic HLL into the AST. See issue 362 and issue 701 for current status.

  3. A SPIR-V back end for translating the AST to SPIR-V.

  4. A standalone wrapper, glslangValidator, that can be used as a command-line tool for the above.

How to add a feature protected by a version/extension/stage/profile: See the comment in glslang/MachineIndependent/Versions.cpp.

Tasks waiting to be done are documented as GitHub issues.

Execution of Standalone Wrapper

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 shader

There is also a non-shader extension

  • .conf for a configuration file of limits, see usage statement for example


Instead 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.


  • A C++11 compiler. (For MSVS: 2015 is recommended, 2013 is fully supported/tested, and 2010 support is attempted, but not tested.)
  • CMake: for generating compilation targets.
  • make: Linux, ninja is an alternative, if configured.
  • Python 2.7: for executing SPIRV-Tools scripts. (Optional if not using SPIRV-Tools.)
  • bison: optional, but needed when changing the grammar (glslang.y).
  • googletest: optional, but should use if making any changes to glslang.

Build steps

The following steps assume a Bash shell. On Windows, that could be the Git Bash shell or some other shell of your choosing.

1) Check-Out this project

cd <parent of where you want glslang to be>
git clone

2) Check-Out External Projects

cd <the directory glslang was cloned to, "External" will be a subdirectory>
git clone External/googletest

If you wish to assure that SPIR-V generated from HLSL is legal for Vulkan, or wish to invoke -Os to reduce SPIR-V size from HLSL or GLSL, install spirv-tools with this:


3) Configure

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

For building on Linux:

cmake -DCMAKE_BUILD_TYPE={Debug|Release|RelWithDebInfo} \
      -DCMAKE_INSTALL_PREFIX="$(pwd)/install" $SOURCE_DIR

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).

4) Build and Install

# for Linux:
make -j4 install

# for Windows:
cmake --build . --config {Release|Debug|MinSizeRel|RelWithDebInfo} \
      --target install

If using MSVC, after running CMake to configure, use the Configuration Manager to check the INSTALL project.

If you need to change the GLSL grammar

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:

bison --defines=MachineIndependent/glslang_tab.cpp.h
      -t MachineIndependent/glslang.y
      -o MachineIndependent/glslang_tab.cpp

The above command is also available in the bash script at glslang/updateGrammar.


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.

Running 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:


# for Linux:

# for Windows:
ctest -C {Debug|Release|RelWithDebInfo|MinSizeRel}

# or, run the test binary directly
# (which gives more fine-grained control like filtering):

Running runtests script-backed tests:

cd $SOURCE_DIR/Test && ./runtests

Contributing tests

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.

Programmatic Interfaces

Another piece of software can programmatically translate shaders to an AST using one of two different interfaces:

  • A new C++ class-oriented interface, or
  • The original C functional interface

The main() in StandAlone/StandAlone.cpp shows examples using both styles.

C++ Class Interface (new, preferred)

This interface is in roughly the last 1/3 of ShaderLang.h. It is in the glslang namespace and contains the following.

const char* GetEsslVersionString();
const char* GetGlslVersionString();
bool InitializeProcess();
void FinalizeProcess();

class TShader
    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

See ShaderLang.h and the usage of it in StandAlone/StandAlone.cpp for more details.

C Functional Interface (orignal)

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 backend 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.

Basic Internal Operation

  • 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 propogated 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