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

Pulls in the following:
2572b19 HLSL: Turn on reflection, with basic test file, to catch regressions.
6b71c40 HLSL: Remove extraneous built-in member decorations for IO structs used in non-IO situations.
86f7138 HLSL: Add string basic type and recognize string declaration grammar.
eee9d53 Track separate entry-point names and mangled names...
632f575 Merge pull request #512 from steve-lunarg/liveness-traverser
5571730 Refactor TLiveTraverser from the former reflection traverser, for future use in binding mapping.
6fccb3c Non-functional: Sweep through the stack for consistent with "main" and entry point.
142785f HLSL: Change the final syntax-error printf to go to the infoLog.
28b2814 HLSL: Fix assert: ensure flattened shadow is EvqTemporary.
5159d4f HLSL: Intercept flatten aggregates passed to a function input, and copy member-by-member.
f911500 HLSL: Non-functional; make flatten semantics be about aggregates, not just structures.
fcea302 HLSL: Fix bug in previous checkin when non-flattened objects are not simple l-values.
d2ce838 HLSL: Handle flatten for reads from flatten structs and parameter passing.
34e7ee7 HLSL: Improve setting and testing of interpolation qualifiers.
d21baed HLSL: Flatten whole-struct assigns and returns when targeting flattened I/O structs.
f8e494c HLSL: Flatten all input/output structs, regardless of stage.
7dc630f HLSL: Flatten a return struct from an entry point and assign locations after flattening.
7f70212 HLSL: return correct error when HLSL parsing fails.
315b6b9 Merge pull request #508 from amdrexu/bugfix
64b9743 SPV: Support simultaneous l-value swizzle and dynamic component selection.
deb4940 HLSL: Register all entry-point in/out as part of the interface.
b3e24e4 SPV: Fix issue #506: generalize struct deep copy to include arrays.
cd0a78a HLSL: Flatten vertex input and fragment output structures.
6295c27 Merge pull request #505 from steve-lunarg/rowmajor-fix-2a
297ae21 WIP: HLSL: Treat HLSL rows as GLSL columns.
d403229 HLSL: Report an error if SPIR-V for Vulkan wasn't selected.
a21187a Merge branch 'amdrexu-bugfix2'
4bfb32e Merge branch 'bugfix2' of into amdrexu-bugfix2
3152718 Merge pull request #503 from amdrexu/feature3
c9f3492 SPV: Use OpBitcast to implement 4 pack/unpack built-in functions.
99c4dd1 Preprocessor: UINT_MAX is translated to constant incorrectly.
cfd7ce8 HLSL: Support register(..., spaceN) for setting the descriptor set.
e3218e2 HLSL: Accept layout(...) also as a post-decl.  Issue #454.
7735b94 HLSL Non-Functional: Move to more robust capturing of postDecls into a qualifier.
b804de6 HLSL: Track binding numbers to struct instances; fixes issue #496.
58d2843 Merge pull request #498 from amdrexu/bugfix
64bcfdb Parser: Add 64-bit type conversion for specialization constant.
7d01bd6 HLSL: Handle swizzles on vectors of size 1. Addresses issue #453.
841db35 HLSL: Fix issue #442, smear and truncate shape conversions for == and !=.
07350f3 HLSL: Handle "fake" entry points, by undoing their built-in variable declarations.
9e07953 HLSL: Handle greater/less depth modes. Fixes issue #489.
a305166 HLSL: Error if funcion with return type doesn't return a value.
1a4b775 HLSL: Correct line numbers for function definitions.
4bf7155 SPV: Flatten structs for copy when they are GLSL type aliases.
31207bc Merge pull request #495 from steve-lunarg/remapper-tests-2
65564a4 Remapper: move remapper tests into the glslangtests executable.
f2b7f33 SPV: Tighten up number of struct-types declared based on decoration.
5e56423 Front-ends: Remove now defunct afterEOF and related, use scanner's instead.
830b0cc HLSL: Start location numbering with the entry-point return value.
a05d8b5 HLSL: Remove recent change to put locations on SV_TARGET*.
510d83b HLSL: Create test results for the previous commits.
335fc28 Merge branch 'dankbaker-HLSL_Semantic_Mapping'
81d4714 Merge branch 'HLSL_Semantic_Mapping' of into dankbaker-HLSL_Semantic_Mapping
a88ef39 Merge pull request #490 from KhronosGroup/hlsl-output-return
6f220c0 HLSL: Setting SV_DEPTHGREATEREQUAL and SV_DEPTHLESSEQUAL to EbvFragDepth for now
6fd31fd Merge branch 'hlsl-output-return' of into hlsl-output-return
6a70eb7 HLSL: Emulate write-to-output on return-from-entry-point, for return value.
be2f6b0 HLSL: Emulate write-to-output on return-from-entry-point, for return value.
81cd764 Non-functional: Add some missing const, related to signature selection.
1389e3e Merge pull request #488 from antiagainst/c4996-warning
424cf80 Disable C4996 (secure CRT) recommendation on Windows for strtok().
f00c245 Merge pull request #473 from steve-lunarg/remapper-tests
e3f2c8f HLSL: Include shape-changing conversions in overloaded signature selection.
26aa8a4 HLSL: Format updates and some minor adjustments to SV_ handling
90dd70f HLSL: Allow arbitrary baseType -> baseType conversion of calling arguments.
a845641 WIP: SPV Remapper: add remapper test framework
deec03c First stab at system value interpretation
4c3a7fd Merge pull request #483 from steve-lunarg/precise-fix-2
36e87d0 HLSL: add precise keyword
fcc0aa3 HLSL: Switch to generic selector, but using GLSL #version 400 rules.
ab89bbe Merge branch 'overloaded-400' of
32c169d Front-end: Warn for likely missed change in default precisions.
54571c2 Vulkan: Have desktop shaders respect precision qualifiers.
4d53564 Front-End: Non-ES trigger for processing precision qualifiers.
219b025 Non-functional: Fix commit 98f164ec488f85af5a44b701477a34e810f2deb1.
98f164e Merge pull request #461 from dankbaker/Error_Message_Fixes_for_HLSL
6577a0e Merge pull request #476 from steve-lunarg/string-literals
3de0a6d Merge pull request #477 from amdrexu/bugfix
2bbbe06 SPV: Some group invocation operations should be applied to scalars.
efe9724 HLSL: Add EHTokStringConstant, so that string attributes may be parsed
3702348 Front-end: Add a function selector under implicit type conversion.
afe6e9c HLSL and standalone, modifying Standalone to send filename as string source, and HLSL backend will use this to print a better error mesage when things fail
0a04b4d Front-end/Non-functional: Add some const/auto, useful for upcoming changes.
b9e3912 HLSL: Partially address issue #463: accept GLSL layout(...).
78a8b07 Merge pull request #471 from steve-lunarg/remapper-literal64-b
811d9f4 WIP: SPIRV remapper: allow 64 bit literals in OperandVariableLiteralId class iteration

Test: ndk/ on Linux; manually run unit tests on Windows
Change-Id: Idf45834ad75a84a8792b0ac98858796b53ede46e
tree: e8322bffddd42cce5ec11e016e2ba0fc66f5f04f
  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. 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.

  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



  • CMake: for generating compilation targets.
  • bison: optional, but needed when changing the grammar (glslang.y).
  • googletest: optional, but should use if making any changes to glslang.

Build steps

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

3) Configure

Assume the source directory is $SOURCE_DIR and the build directory is $BUILD_DIR:

For building on Linux (assuming using the Ninja generator):


cmake -GNinja -DCMAKE_BUILD_TYPE={Debug|Release|RelWithDebInfo} \

For building on Windows:

# 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:
ninja 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
    bool parse(...);
    void setStrings(...);
    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