commit | 1be4d493df6ff0448b720f87888effafeb055175 | [log] [tgz] |
---|---|---|
author | Olli Etuaho <oetuaho@nvidia.com> | Tue Sep 27 10:15:38 2016 |
committer | Commit Bot <commit-bot@chromium.org> | Wed Sep 28 10:55:16 2016 |
tree | d46a658d968078252c1d0188b2d9e5beb2e66722 | |
parent | 9a8d366a992691e6e4ab45d985733d58ff9bbc62 [diff] |
Fix handling integer overflow in constant folding Integer operations that overflow are defined to wrap in the ESSL 3.00.6 spec. Constant folding that happens inside the shader translator should also follow the wrapping rules. The new implementations of wrapping integer addition and subtraction use unsigned integers to perform calculations. Unsigned integers are defined to implement arithmetic in modulo 2^n in the C++ spec. This behavior is also leveraged to implement wrapping unsigned integer multiplication. The implementation of wrapping signed integer multiplication is slightly trickier. The operands are casted to a wider type to perform the multiplication in a way that doesn't overflow, and then the result is truncated and casted back to the narrower integer type. Incorrect tests that expected errors to be generated from integer overflow in constant folding are removed. BUG=chromium:637050 TEST=angle_unittests Change-Id: I0de7e25881d254803455fbf22907c192f49d09ff Reviewed-on: https://chromium-review.googlesource.com/390252 Commit-Queue: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Corentin Wallez <cwallez@chromium.org>
The goal of ANGLE is to allow users of multiple operating systems to seamlessly run WebGL and other OpenGL ES content by translating OpenGL ES API calls to one of the hardware-supported APIs available for that platform. ANGLE currently provides translation from OpenGL ES 2.0 and 3.0 to desktop OpenGL, OpenGL ES, Direct3D 9, and Direct3D 11. Support for translation from OpenGL ES to Vulkan is underway, and future plans include compute shader support (ES 3.1) and MacOS support.
Direct3D 9 | Direct3D 11 | Desktop GL | GL ES | Vulkan | |
---|---|---|---|---|---|
OpenGL ES 2.0 | complete | complete | complete | complete | in progress |
OpenGL ES 3.0 | complete | complete | in progress | not started | |
OpenGL ES 3.1 | not started | in progress | in progress | not started |
Direct3D 9 | Direct3D 11 | Desktop GL | GL ES | Vulkan | |
---|---|---|---|---|---|
Windows | complete | complete | complete | complete | in progress |
Linux | complete | planned | |||
Mac OS X | in progress | ||||
Chrome OS | complete | planned | |||
Android | complete | planned |
ANGLE v1.0.772 was certified compliant by passing the ES 2.0.3 conformance tests in October 2011. ANGLE also provides an implementation of the EGL 1.4 specification.
ANGLE is used as the default WebGL backend for both Google Chrome and Mozilla Firefox on Windows platforms. Chrome uses ANGLE for all graphics rendering on Windows, including the accelerated Canvas2D implementation and the Native Client sandbox environment.
Portions of the ANGLE shader compiler are used as a shader validator and translator by WebGL implementations across multiple platforms. It is used on Mac OS X, Linux, and in mobile variants of the browsers. Having one shader validator helps to ensure that a consistent set of GLSL ES shaders are accepted across browsers and platforms. The shader translator can be used to translate shaders to other shading languages, and to optionally apply shader modifications to work around bugs or quirks in the native graphics drivers. The translator targets Desktop GLSL, Direct3D HLSL, and even ESSL for native GLES2 platforms.
ANGLE repository is hosted by Chromium project and can be browsed online or cloned with
git clone https://chromium.googlesource.com/angle/angle
View the Dev setup instructions. For generating a Windows Store version of ANGLE view the Windows Store instructions
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