translator: Fix variable collection for gl_DepthRange.

*re-land with Linux fixes, and fix for locations*

This built-in uniform wasn't being collected in VariableInfo.cpp.
Also remove the existing workaround for D3D gl_DepthRange
collection.

BUG=angleproject:991
BUG=478570

Change-Id: Iba84651bfc58f82fd4ce039421874f561f83c348
Reviewed-on: https://chromium-review.googlesource.com/268840
Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>

include/GLSLANG/ShaderVars.h

@@ -70,6 +70,8 @@ struct COMPILER_EXPORT ShaderVariable
                               const ShaderVariable **leafVar,
                               std::string* originalFullName) const;
 
+    bool isBuiltIn() const { return name.compare(0, 3, "gl_") == 0; }
+
     GLenum type;
     GLenum precision;
     std::string name;

src/compiler/translator/VariableInfo.cpp

@@ -139,6 +139,7 @@ CollectVariables::CollectVariables(std::vector<sh::Attribute> *attribs,
       mUniforms(uniforms),
       mVaryings(varyings),
       mInterfaceBlocks(interfaceBlocks),
+      mDepthRangeAdded(false),
       mPointCoordAdded(false),
       mFrontFacingAdded(false),
       mFragCoordAdded(false),
@@ -170,6 +171,56 @@ void CollectVariables::visitSymbol(TIntermSymbol *symbol)
     {
         UNREACHABLE();
     }
+    else if (symbolName == "gl_DepthRange")
+    {
+        ASSERT(symbol->getQualifier() == EvqUniform);
+
+        if (!mDepthRangeAdded)
+        {
+            Uniform info;
+            const char kName[] = "gl_DepthRange";
+            info.name = kName;
+            info.mappedName = kName;
+            info.type = GL_STRUCT_ANGLEX;
+            info.arraySize = 0;
+            info.precision = GL_NONE;
+            info.staticUse = true;
+
+            ShaderVariable nearInfo;
+            const char kNearName[] = "near";
+            nearInfo.name = kNearName;
+            nearInfo.mappedName = kNearName;
+            nearInfo.type = GL_FLOAT;
+            nearInfo.arraySize = 0;
+            nearInfo.precision = GL_HIGH_FLOAT;
+            nearInfo.staticUse = true;
+
+            ShaderVariable farInfo;
+            const char kFarName[] = "far";
+            farInfo.name = kFarName;
+            farInfo.mappedName = kFarName;
+            farInfo.type = GL_FLOAT;
+            farInfo.arraySize = 0;
+            farInfo.precision = GL_HIGH_FLOAT;
+            farInfo.staticUse = true;
+
+            ShaderVariable diffInfo;
+            const char kDiffName[] = "diff";
+            diffInfo.name = kDiffName;
+            diffInfo.mappedName = kDiffName;
+            diffInfo.type = GL_FLOAT;
+            diffInfo.arraySize = 0;
+            diffInfo.precision = GL_HIGH_FLOAT;
+            diffInfo.staticUse = true;
+
+            info.fields.push_back(nearInfo);
+            info.fields.push_back(farInfo);
+            info.fields.push_back(diffInfo);
+
+            mUniforms->push_back(info);
+            mDepthRangeAdded = true;
+        }
+    }
     else
     {
         switch (symbol->getQualifier())
@@ -192,7 +243,6 @@ void CollectVariables::visitSymbol(TIntermSymbol *symbol)
 
                     // Set static use on the parent interface block here
                     namedBlock->staticUse = true;
-
                 }
                 else
                 {
@@ -200,7 +250,7 @@ void CollectVariables::visitSymbol(TIntermSymbol *symbol)
                 }
 
                 // It's an internal error to reference an undefined user uniform
-                ASSERT(symbolName.compare(0, 3, "gl_") == 0 || var);
+                ASSERT(symbolName.compare(0, 3, "gl_") != 0 || var);
             }
             break;
           case EvqFragCoord:

src/compiler/translator/VariableInfo.h

@@ -47,6 +47,7 @@ class CollectVariables : public TIntermTraverser
 
     std::map<std::string, InterfaceBlockField *> mInterfaceBlockFields;
 
+    bool mDepthRangeAdded;
     bool mPointCoordAdded;
     bool mFrontFacingAdded;
     bool mFragCoordAdded;

src/libANGLE/Shader.h

@@ -45,7 +45,6 @@ struct PackedVarying : public sh::Varying
     {}
 
     bool registerAssigned() const { return registerIndex != GL_INVALID_INDEX; }
-    bool isBuiltIn() const { return name.compare(0, 3, "gl_") == 0; }
 
     void resetRegisterAssignment()
     {

src/libANGLE/Uniform.cpp

@@ -80,6 +80,11 @@ bool LinkedUniform::isSampler() const
     return IsSamplerType(type);
 }
 
+bool LinkedUniform::isBuiltIn() const
+{
+    return name.compare(0, 3, "gl_") == 0;
+}
+
 UniformBlock::UniformBlock(const std::string &name, unsigned int elementIndex, unsigned int dataSize)
     : name(name),
       elementIndex(elementIndex),

src/libANGLE/Uniform.h

@@ -32,6 +32,7 @@ struct LinkedUniform : angle::NonCopyable
     bool isInDefaultBlock() const;
     size_t dataSize() const;
     bool isSampler() const;
+    bool isBuiltIn() const;
 
     const GLenum type;
     const GLenum precision;

src/libANGLE/renderer/d3d/ProgramD3D.cpp

@@ -1375,7 +1375,9 @@ bool ProgramD3D::linkUniforms(gl::InfoLog &infoLog, const gl::Shader &vertexShad
 
         if (uniform.staticUse)
         {
-            defineUniformBase(vertexShaderD3D, uniform, vertexShaderD3D->getUniformRegister(uniform.name));
+            unsigned int registerBase = uniform.isBuiltIn() ? GL_INVALID_INDEX :
+                vertexShaderD3D->getUniformRegister(uniform.name);
+            defineUniformBase(vertexShaderD3D, uniform, registerBase);
         }
     }
 
@@ -1385,7 +1387,9 @@ bool ProgramD3D::linkUniforms(gl::InfoLog &infoLog, const gl::Shader &vertexShad
 
         if (uniform.staticUse)
         {
-            defineUniformBase(fragmentShaderD3D, uniform, fragmentShaderD3D->getUniformRegister(uniform.name));
+            unsigned int registerBase = uniform.isBuiltIn() ? GL_INVALID_INDEX :
+                fragmentShaderD3D->getUniformRegister(uniform.name);
+            defineUniformBase(fragmentShaderD3D, uniform, registerBase);
         }
     }
 
@@ -1396,21 +1400,17 @@ bool ProgramD3D::linkUniforms(gl::InfoLog &infoLog, const gl::Shader &vertexShad
 
     initializeUniformStorage();
 
-    // special case for gl_DepthRange, the only built-in uniform (also a struct)
-    if (vertexShaderD3D->usesDepthRange() || fragmentShaderD3D->usesDepthRange())
-    {
-        const sh::BlockMemberInfo &defaultInfo = sh::BlockMemberInfo::getDefaultBlockInfo();
-
-        mUniforms.push_back(new gl::LinkedUniform(GL_FLOAT, GL_HIGH_FLOAT, "gl_DepthRange.near", 0, -1, defaultInfo));
-        mUniforms.push_back(new gl::LinkedUniform(GL_FLOAT, GL_HIGH_FLOAT, "gl_DepthRange.far", 0, -1, defaultInfo));
-        mUniforms.push_back(new gl::LinkedUniform(GL_FLOAT, GL_HIGH_FLOAT, "gl_DepthRange.diff", 0, -1, defaultInfo));
-    }
-
     return true;
 }
 
 void ProgramD3D::defineUniformBase(const ShaderD3D *shader, const sh::Uniform &uniform, unsigned int uniformRegister)
 {
+    if (uniformRegister == GL_INVALID_INDEX)
+    {
+        defineUniform(shader, uniform, uniform.name, nullptr);
+        return;
+    }
+
     ShShaderOutput outputType = shader->getCompilerOutputType();
     sh::HLSLBlockEncoder encoder(sh::HLSLBlockEncoder::GetStrategyFor(outputType));
     encoder.skipRegisters(uniformRegister);
@@ -1427,7 +1427,8 @@ void ProgramD3D::defineUniform(const ShaderD3D *shader, const sh::ShaderVariable
         {
             const std::string &elementString = (uniform.isArray() ? ArrayString(elementIndex) : "");
 
-            encoder->enterAggregateType();
+            if (encoder)
+                encoder->enterAggregateType();
 
             for (size_t fieldIndex = 0; fieldIndex < uniform.fields.size(); fieldIndex++)
             {
@@ -1437,13 +1438,14 @@ void ProgramD3D::defineUniform(const ShaderD3D *shader, const sh::ShaderVariable
                 defineUniform(shader, field, fieldFullName, encoder);
             }
 
-            encoder->exitAggregateType();
+            if (encoder)
+                encoder->exitAggregateType();
         }
     }
     else // Not a struct
     {
         // Arrays are treated as aggregate types
-        if (uniform.isArray())
+        if (uniform.isArray() && encoder)
         {
             encoder->enterAggregateType();
         }
@@ -1451,29 +1453,36 @@ void ProgramD3D::defineUniform(const ShaderD3D *shader, const sh::ShaderVariable
         gl::LinkedUniform *linkedUniform = getUniformByName(fullName);
 
         // Advance the uniform offset, to track registers allocation for structs
-        sh::BlockMemberInfo blockInfo = encoder->encodeType(uniform.type, uniform.arraySize, false);
+        sh::BlockMemberInfo blockInfo = encoder ?
+            encoder->encodeType(uniform.type, uniform.arraySize, false) :
+            sh::BlockMemberInfo::getDefaultBlockInfo();
 
         if (!linkedUniform)
         {
             linkedUniform = new gl::LinkedUniform(uniform.type, uniform.precision, fullName, uniform.arraySize,
                                                   -1, sh::BlockMemberInfo::getDefaultBlockInfo());
             ASSERT(linkedUniform);
-            linkedUniform->registerElement = sh::HLSLBlockEncoder::getBlockRegisterElement(blockInfo);
+
+            if (encoder)
+                linkedUniform->registerElement = sh::HLSLBlockEncoder::getBlockRegisterElement(blockInfo);
             mUniforms.push_back(linkedUniform);
         }
 
-        if (shader->getShaderType() == GL_FRAGMENT_SHADER)
+        if (encoder)
         {
-            linkedUniform->psRegisterIndex = sh::HLSLBlockEncoder::getBlockRegister(blockInfo);
+            if (shader->getShaderType() == GL_FRAGMENT_SHADER)
+            {
+                linkedUniform->psRegisterIndex = sh::HLSLBlockEncoder::getBlockRegister(blockInfo);
+            }
+            else if (shader->getShaderType() == GL_VERTEX_SHADER)
+            {
+                linkedUniform->vsRegisterIndex = sh::HLSLBlockEncoder::getBlockRegister(blockInfo);
+            }
+            else UNREACHABLE();
         }
-        else if (shader->getShaderType() == GL_VERTEX_SHADER)
-        {
-            linkedUniform->vsRegisterIndex = sh::HLSLBlockEncoder::getBlockRegister(blockInfo);
-        }
-        else UNREACHABLE();
 
         // Arrays are treated as aggregate types
-        if (uniform.isArray())
+        if (uniform.isArray() && encoder)
         {
             encoder->exitAggregateType();
         }
@@ -1934,9 +1943,12 @@ bool ProgramD3D::indexUniforms(gl::InfoLog &infoLog, const gl::Caps &caps)
             }
         }
 
-        for (unsigned int arrayElementIndex = 0; arrayElementIndex < uniform.elementCount(); arrayElementIndex++)
+        for (unsigned int arrayIndex = 0; arrayIndex < uniform.elementCount(); arrayIndex++)
         {
-            mUniformIndex.push_back(gl::VariableLocation(uniform.name, arrayElementIndex, uniformIndex));
+            if (!uniform.isBuiltIn())
+            {
+                mUniformIndex.push_back(gl::VariableLocation(uniform.name, arrayIndex, uniformIndex));
+            }
         }
     }
 

src/libANGLE/renderer/d3d/ShaderD3D.cpp

@@ -218,7 +218,7 @@ void ShaderD3D::compileToHLSL(ShHandle compiler, const std::string &source)
         {
             const sh::Uniform &uniform = mUniforms[uniformIndex];
 
-            if (uniform.staticUse)
+            if (uniform.staticUse && !uniform.isBuiltIn())
             {
                 unsigned int index = static_cast<unsigned int>(-1);
                 bool getUniformRegisterResult = ShGetUniformRegister(compiler, uniform.name, &index);

src/tests/angle_end2end_tests.gypi

@@ -61,6 +61,7 @@
     },
     'dependencies':
     [
+        '<(angle_path)/src/angle.gyp:libANGLE',
         '<(angle_path)/src/angle.gyp:libEGL',
         '<(angle_path)/src/angle.gyp:libGLESv2',
         '<(angle_path)/src/tests/tests.gyp:angle_test_support',

src/tests/compiler_tests/CollectVariables_test.cpp

@@ -19,8 +19,10 @@ class CollectVariablesTest : public testing::Test
 {
   public:
     CollectVariablesTest(GLenum shaderType)
-        : mShaderType(shaderType)
-    {}
+        : mShaderType(shaderType),
+          mTranslator(nullptr)
+    {
+    }
 
   protected:
     virtual void SetUp()
@@ -29,14 +31,67 @@ class CollectVariablesTest : public testing::Test
         ShInitBuiltInResources(&resources);
         resources.MaxDrawBuffers = 8;
 
+        initTranslator(resources);
+    }
+
+    virtual void TearDown()
+    {
+        SafeDelete(mTranslator);
+    }
+
+    void initTranslator(const ShBuiltInResources &resources)
+    {
+        SafeDelete(mTranslator);
         mTranslator = new TranslatorGLSL(
             mShaderType, SH_GLES3_SPEC, SH_GLSL_COMPATIBILITY_OUTPUT);
         ASSERT_TRUE(mTranslator->Init(resources));
     }
 
-    virtual void TearDown()
+    // For use in the gl_DepthRange tests.
+    void validateDepthRangeShader(const std::string &shaderString)
     {
-        delete mTranslator;
+        const char *shaderStrings[] = { shaderString.c_str() };
+        ASSERT_TRUE(mTranslator->compile(shaderStrings, 1, SH_VARIABLES));
+
+        const std::vector<sh::Uniform> &uniforms = mTranslator->getUniforms();
+        ASSERT_EQ(1u, uniforms.size());
+
+        const sh::Uniform &uniform = uniforms[0];
+        EXPECT_EQ("gl_DepthRange", uniform.name);
+        ASSERT_TRUE(uniform.isStruct());
+        ASSERT_EQ(3u, uniform.fields.size());
+
+        bool foundNear = false;
+        bool foundFar = false;
+        bool foundDiff = false;
+
+        for (const auto &field : uniform.fields)
+        {
+            if (field.name == "near")
+            {
+                EXPECT_FALSE(foundNear);
+                foundNear = true;
+            }
+            else if (field.name == "far")
+            {
+                EXPECT_FALSE(foundFar);
+                foundFar = true;
+            }
+            else
+            {
+                ASSERT_EQ("diff", field.name);
+                EXPECT_FALSE(foundDiff);
+                foundDiff = true;
+            }
+
+            EXPECT_EQ(0u, field.arraySize);
+            EXPECT_FALSE(field.isStruct());
+            EXPECT_GLENUM_EQ(GL_HIGH_FLOAT, field.precision);
+            EXPECT_TRUE(field.staticUse);
+            EXPECT_GLENUM_EQ(GL_FLOAT, field.type);
+        }
+
+        EXPECT_TRUE(foundNear && foundFar && foundDiff);
     }
 
     GLenum mShaderType;
@@ -369,3 +424,27 @@ TEST_F(CollectVertexVariablesTest, VaryingInterpolation)
     EXPECT_EQ("vary", varying->name);
     EXPECT_EQ(sh::INTERPOLATION_CENTROID, varying->interpolation);
 }
+
+// Test for builtin uniform "gl_DepthRange" (Vertex shader)
+TEST_F(CollectVertexVariablesTest, DepthRange)
+{
+    const std::string &shaderString =
+        "attribute vec4 position;\n"
+        "void main() {\n"
+        "   gl_Position = position + vec4(gl_DepthRange.near, gl_DepthRange.far, gl_DepthRange.diff, 1.0);\n"
+        "}\n";
+
+    validateDepthRangeShader(shaderString);
+}
+
+// Test for builtin uniform "gl_DepthRange" (Fragment shader)
+TEST_F(CollectFragmentVariablesTest, DepthRange)
+{
+    const std::string &shaderString =
+        "precision mediump float;\n"
+        "void main() {\n"
+        "   gl_FragColor = vec4(gl_DepthRange.near, gl_DepthRange.far, gl_DepthRange.diff, 1.0);\n"
+        "}\n";
+
+    validateDepthRangeShader(shaderString);
+}

src/tests/end2end_tests/GLSLTest.cpp

@@ -1,5 +1,14 @@
+//
+// Copyright 2015 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
 #include "ANGLETest.h"
 
+#include "libANGLE/Context.h"
+#include "libANGLE/Program.h"
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these tests should be run against.
 ANGLE_TYPED_TEST_CASE(GLSLTest, ES2_D3D9, ES2_D3D11);
 
@@ -1067,3 +1076,36 @@ TYPED_TEST(GLSLTest, StructSpecifiersUniforms)
     GLuint program = CompileProgram(mSimpleVSSource, fragmentShaderSource);
     EXPECT_NE(0u, program);
 }
+
+// Test that gl_DepthRange is not stored as a uniform location. Since uniforms
+// beginning with "gl_" are filtered out by our validation logic, we must
+// bypass the validation to test the behaviour of the implementation.
+// (note this test is still Impl-independent)
+TYPED_TEST(GLSLTest, DepthRangeUniforms)
+{
+    const std::string fragmentShaderSource = SHADER_SOURCE
+    (
+        precision mediump float;
+
+        void main()
+        {
+            gl_FragColor = vec4(gl_DepthRange.near, gl_DepthRange.far, gl_DepthRange.diff, 1);
+        }
+    );
+
+    GLuint program = CompileProgram(mSimpleVSSource, fragmentShaderSource);
+    EXPECT_NE(0u, program);
+
+    // dive into the ANGLE internals, so we can bypass validation.
+    gl::Context *context = reinterpret_cast<gl::Context *>(getEGLWindow()->getContext());
+    gl::Program *glProgram = context->getProgram(program);
+    GLint nearIndex = glProgram->getUniformLocation("gl_DepthRange.near");
+    EXPECT_EQ(-1, nearIndex);
+
+    // Test drawing does not throw an exception.
+    drawQuad(program, "inputAttribute", 0.5f);
+
+    EXPECT_GL_NO_ERROR();
+
+    glDeleteProgram(program);
+}

src/tests/end2end_tests/QueryDisplayAttribTest.cpp

@@ -1,5 +1,16 @@
+//
+// Copyright 2015 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#ifndef ANGLE_ENABLE_D3D9
 #define ANGLE_ENABLE_D3D9
+#endif
+
+#ifndef ANGLE_ENABLE_D3D11
 #define ANGLE_ENABLE_D3D11
+#endif
 
 #include "ANGLETest.h"
 #include "com_utils.h"