Commit ebe943e2faef27be83f3dcaf4213e465ab9eee5c
2021-07-29T11:19:33
Vulkan: SPIR-V Gen: Fix gl_Clip/CullDistance These built-ins can be redeclared in the shader. The translator took these redeclarations (and gl_LastFragData) as UserDefined symbols. There were a number of hacks such as in name generation and CollectVariables, to special-case these redeclarations. This change instead makes sure that these variables continue to be considered built-ins with the appropriate qualifiers. A number of fixes are made accordingly: - Hacks are removed. - In fragment shaders, ANGLEClipDistance was initialized with gl_ClipDistance for further use by the shader. The code generation however mistakenly produced `gl_ClipDistance[0] = ANGLEClipDistance[0];`, which caused compilation failures by glslang, but passed the tests accidentally because they expected link failures (see next item). - CollectVariables is fixed to correctly collect gl_Clip/CullDistance in fragment shaders; previously they were collected as output varyings, and therefore the aforementioned link error was not produced in the tests after the compilation error was fixed. Additional fixes: - The transformation of gl_Clip/CullDistance was always ever done on one of them due to misplaced breaks in the loop that detected their presence. - The transformation of gl_CullDistance was skipped when it was not redeclared. Validation is added to make sure these built-ins always have the correct qualifier even when redeclared. SPIR-V gen support for these variables have been fixed as well. Bug: angleproject:4889 Change-Id: Ic8bf2c508357035cb937ef41a28ae22ffc533ebe Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3059921 Reviewed-by: Tim Van Patten <timvp@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>