-Also see the Khronos landing page for glslang as a reference front end:
+# News
-https://www.khronos.org/opengles/sdk/tools/Reference-Compiler/
+1. Visual Studio 2013 is no longer supported
+
+ [As scheduled](https://github.com/KhronosGroup/glslang/blob/9eef54b2513ca6b40b47b07d24f453848b65c0df/README.md#planned-deprecationsremovals),
+Microsoft Visual Studio 2013 is no longer officially supported. \
+ Please upgrade to at least Visual Studio 2015.
+
+2. 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.
-The above page includes where to get binaries, and is kept up to date
-regarding the feature level of glslang.
+3. If you get a new **compilation error due to a missing header**, it might be caused by this planned removal:
-glslang
-=======
+**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](https://github.com/KhronosGroup/SPIRV-Headers) instead.
[](https://travis-ci.org/KhronosGroup/glslang)
[](https://ci.appveyor.com/project/Khronoswebmaster/glslang/branch/master)
-An OpenGL and OpenGL ES shader front end and validator.
+# Glslang Components and Status
There are several components:
-1. A GLSL/ESSL front-end for reference validation and translation of GLSL/ESSL into an AST.
+### Reference Validator and GLSL/ESSL -> AST Front End
+
+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.
+
+### HLSL -> AST Front End
+
+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](https://github.com/Microsoft/DirectXShaderCompiler), which receives a much larger investment and attempts to have definitive/reference-level semantics.
+
+See [issue 362](https://github.com/KhronosGroup/glslang/issues/362) and [issue 701](https://github.com/KhronosGroup/glslang/issues/701) for current status.
+
+### AST -> SPIR-V Back End
+
+Translates glslang's AST to the Khronos-specified SPIR-V intermediate language.
+
+**Status**: Virtually complete.
+
+### Reflector
+
+An API for getting reflection information from the AST, reflection types/variables/etc. from the HLL source (not the SPIR-V).
-2. An HLSL front-end for translation of a broad generic HLL into the AST. See [issue 362](https://github.com/KhronosGroup/glslang/issues/362) and [issue 701](https://github.com/KhronosGroup/glslang/issues/701) for current status.
+**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.
-3. A SPIR-V back end for translating the AST to SPIR-V.
+### Standalone Wrapper
-4. A standalone wrapper, `glslangValidator`, that can be used as a command-line tool for the above.
+`glslangValidator` is command-line tool for accessing the functionality above.
-How to add a feature protected by a version/extension/stage/profile: See the
-comment in `glslang/MachineIndependent/Versions.cpp`.
+Status: Complete.
Tasks waiting to be done are documented as GitHub issues.
-Execution of Standalone Wrapper
--------------------------------
+## Other References
+
+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.
+
+# How to Use Glslang
+
+## 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,
There is also a non-shader extension
* `.conf` for a configuration file of limits, see usage statement for example
-Building
---------
+## Building
Instead of building manually, you can also download the binaries for your
platform directly from the [master-tot release][master-tot-release] on GitHub.
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
+#### 1) Check-Out this project
```bash
cd <parent of where you want glslang to be>
```
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:
+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:
```bash
./update_glslang_sources.py
# "Release" (for CMAKE_BUILD_TYPE) could also be "Debug" or "RelWithDebInfo"
```
+For building on Android:
+```bash
+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:
```bash
the web grammar subset (see more about the web subset in the next section).
### Building to WASM for the Web and Node
+### Building a standalone JS/WASM library for the Web and Node
-Use the steps in [Build Steps](#build-steps), which following notes/exceptions:
-* For building the web subset of core glslang:
- + update the grammar: run `m4` with `-DGLSLANG_WEB`, or simply execute
- `updateGrammar web` from the glslang subdirectory
- + set `-DENABLE_HLSL=OFF -DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF`
- + turn on `-DENABLE_GLSLANG_WEB=ON`
- + optionally, for GLSL compilation error messages, turn on `-DENABLE_GLSLANG_WEB_DEVEL=ON`
+Use the steps in [Build Steps](#build-steps), with the following notes/exceptions:
* `emsdk` needs to be present in your executable search path, *PATH* for
- Bash-like enivironments
- + Instructions located
- [here](https://emscripten.org/docs/getting_started/downloads.html#sdk-download-and-install)
+ Bash-like environments:
+ + [Instructions located here](https://emscripten.org/docs/getting_started/downloads.html#sdk-download-and-install)
* Wrap cmake call: `emcmake cmake`
-* To get a 'true' minimized build, make sure to use `brotli` to compress the .js
+* Set `-DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF`.
+* Set `-DENABLE_HLSL=OFF` if HLSL is not needed.
+* For a standalone JS/WASM library, turn on `-DENABLE_GLSLANG_JS=ON`.
+* For building a minimum-size web subset of core glslang:
+ + turn on `-DENABLE_GLSLANG_WEBMIN=ON` (disables HLSL)
+ + execute `updateGrammar web` from the glslang subdirectory
+ (or if using your own scripts, `m4` needs a `-DGLSLANG_WEB` argument)
+ + optionally, for GLSL compilation error messages, turn on
+ `-DENABLE_GLSLANG_WEBMIN_DEVEL=ON`
+* To get a fully minimized build, make sure to use `brotli` to compress the .js
and .wasm files
Example:
```sh
-emcmake cmake -DCMAKE_BUILD_TYPE=Release -DENABLE_GLSLANG_WEB=ON \
+emcmake cmake -DCMAKE_BUILD_TYPE=Release -DENABLE_GLSLANG_JS=ON \
-DENABLE_HLSL=OFF -DBUILD_TESTING=OFF -DENABLE_OPT=OFF -DINSTALL_GTEST=OFF ..
```
-Testing
--------
+## Building glslang - Using vcpkg
+
+You can download and install glslang using the [vcpkg](https://github.com/Microsoft/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](https://github.com/Microsoft/vcpkg) on the vcpkg repository.
+
+## Testing
Right now, there are two test harnesses existing in glslang: one is [Google
Test](gtests/), one is the [`runtests` script](Test/runtests). The former
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.
+
### Contributing tests
Test results should always be included with a pull request that modifies
`localtestlist` to list non-tracked tests. This is automatically read
by `runtests` and included in the `diff` and `bump` process.
-Programmatic Interfaces
------------------------
+## Programmatic Interfaces
Another piece of software can programmatically translate shaders to an AST
using one of two different interfaces:
Reflection queries
```
-For just validating (not generating code), subsitute these calls:
+For just validating (not generating code), substitute these calls:
```cxx
setEnvInput(EShSourceHlsl or EShSourceGlsl, stage, EShClientNone, 0);
details. There is a block comment giving more detail above the calls for
`setEnvInput, setEnvClient, and setEnvTarget`.
-### C Functional Interface (orignal)
+### C Functional Interface (original)
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.
+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:
In practice, `ShCompile()` takes shader strings, default version, and
warning/error and other options for controlling compilation.
-Basic Internal Operation
-------------------------
+## Basic Internal Operation
* Initial lexical analysis is done by the preprocessor in
`MachineIndependent/Preprocessor`, and then refined by a GLSL scanner
* 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
+ 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
- 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`.
[cmake]: https://cmake.org/
[python]: https://www.python.org/
projects / platform / upstream / glslang.git / blobdiff