Vulkan: Fix the issue with unused attributes / varyings

src/compiler/translator/OutputGLSLBase.cpp

@@ -214,7 +214,16 @@ void TOutputGLSLBase::writeLayoutQualifier(TIntermTyped *variable)
     out << ") ";
 }
 
-const char *TOutputGLSLBase::mapQualifierToString(TQualifier qualifier, const TSymbol *symbol)
+void TOutputGLSLBase::writeQualifier(TQualifier qualifier, const TSymbol *symbol)
+{
+    const char *result = mapQualifierToString(qualifier);
+    if (result && result[0] != '\0')
+    {
+        objSink() << result << " ";
+    }
+}
+
+const char *TOutputGLSLBase::mapQualifierToString(TQualifier qualifier)
 {
     if (sh::IsGLSL410OrOlder(mOutput) && mShaderVersion >= 300 &&
         (mCompileOptions & SH_REMOVE_INVARIANT_AND_CENTROID_FOR_ESSL3) != 0)
@@ -265,11 +274,7 @@ void TOutputGLSLBase::writeVariableType(const TType &type, const TSymbol *symbol
     }
     if (qualifier != EvqTemporary && qualifier != EvqGlobal)
     {
-        const char *qualifierString = mapQualifierToString(qualifier, symbol);
-        if (qualifierString && qualifierString[0] != '\0')
-        {
-            out << qualifierString << " ";
-        }
+        writeQualifier(qualifier, symbol);
     }
 
     const TMemoryQualifier &memoryQualifier = type.getMemoryQualifier();

src/compiler/translator/OutputGLSLBase.h

@@ -77,6 +77,7 @@ class TOutputGLSLBase : public TIntermTraverser
     virtual ImmutableString translateTextureFunction(const ImmutableString &name) { return name; }
 
     void declareStruct(const TStructure *structure);
+    virtual void writeQualifier(TQualifier qualifier, const TSymbol *symbol);
 
   private:
     bool structDeclared(const TStructure *structure) const;
@@ -86,7 +87,7 @@ class TOutputGLSLBase : public TIntermTraverser
 
     void writeBuiltInFunctionTriplet(Visit visit, TOperator op, bool useEmulatedFunction);
 
-    const char *mapQualifierToString(TQualifier qualifier, const TSymbol *symbol);
+    const char *mapQualifierToString(TQualifier qualifier);
 
     TInfoSinkBase &mObjSink;
     bool mDeclaringVariable;

src/compiler/translator/OutputVulkanGLSL.cpp

@@ -11,6 +11,7 @@
 
 #include "compiler/translator/OutputVulkanGLSL.h"
 
+#include "compiler/translator/Symbol.h"
 #include "compiler/translator/util.h"
 
 namespace sh
@@ -54,7 +55,6 @@ void TOutputVulkanGLSL::writeLayoutQualifier(TIntermTyped *variable)
 
     TInfoSinkBase &out                      = objSink();
     const TLayoutQualifier &layoutQualifier = type.getLayoutQualifier();
-    out << "layout(";
 
     // This isn't super clean, but it gets the job done.
     // See corresponding code in GlslangWrapper.cpp.
@@ -67,6 +67,10 @@ void TOutputVulkanGLSL::writeLayoutQualifier(TIntermTyped *variable)
     {
         out << "@@ LAYOUT-" << symbol->getName() << " @@";
     }
+    else
+    {
+        out << "layout(";
+    }
 
     if (IsImage(type.getBasicType()) && layoutQualifier.imageInternalFormat != EiifUnspecified)
     {
@@ -74,7 +78,30 @@ void TOutputVulkanGLSL::writeLayoutQualifier(TIntermTyped *variable)
         out << getImageInternalFormatString(layoutQualifier.imageInternalFormat);
     }
 
-    out << ") ";
+    if (!needsCustomLayout)
+    {
+        out << ") ";
+    }
+}
+
+void TOutputVulkanGLSL::writeQualifier(TQualifier qualifier, const TSymbol *symbol)
+{
+    if (qualifier != EvqUniform && qualifier != EvqVaryingIn && qualifier != EvqVaryingOut &&
+        qualifier != EvqAttribute)
+    {
+        TOutputGLSLBase::writeQualifier(qualifier, symbol);
+        return;
+    }
+
+    if (symbol == nullptr)
+    {
+        return;
+    }
+
+    TInfoSinkBase &out = objSink();
+    out << "@@ QUALIFIER-";
+    out << symbol->name().data();
+    out << " @@ ";
 }
 
 void TOutputVulkanGLSL::writeStructType(const TStructure *structure)

src/compiler/translator/OutputVulkanGLSL.h

@@ -31,6 +31,7 @@ class TOutputVulkanGLSL : public TOutputGLSL
 
   protected:
     void writeLayoutQualifier(TIntermTyped *variable) override;
+    void writeQualifier(TQualifier qualifier, const TSymbol *symbol) override;
 };
 
 }  // namespace sh

src/libANGLE/renderer/vulkan/GlslangWrapper.cpp

@@ -28,15 +28,37 @@ namespace rx
 namespace
 {
 
+constexpr char kQualifierMarkerBegin[] = "@@ QUALIFIER-";
+constexpr char kLayoutMarkerBegin[]    = "@@ LAYOUT-";
+constexpr char kMarkerEnd[]            = " @@";
+constexpr char kUniformQualifier[]     = "uniform";
+
 void InsertLayoutSpecifierString(std::string *shaderString,
                                  const std::string &variableName,
                                  const std::string &layoutString)
 {
     std::stringstream searchStringBuilder;
-    searchStringBuilder << "@@ LAYOUT-" << variableName << " @@";
+    searchStringBuilder << kLayoutMarkerBegin << variableName << kMarkerEnd;
     std::string searchString = searchStringBuilder.str();
 
-    angle::ReplaceSubstring(shaderString, searchString, layoutString);
+    if (layoutString != "")
+    {
+        angle::ReplaceSubstring(shaderString, searchString, "layout(" + layoutString + ")");
+    }
+    else
+    {
+        angle::ReplaceSubstring(shaderString, searchString, layoutString);
+    }
+}
+
+void InsertQualifierSpecifierString(std::string *shaderString,
+                                    const std::string &variableName,
+                                    const std::string &replacementString)
+{
+    std::stringstream searchStringBuilder;
+    searchStringBuilder << kQualifierMarkerBegin << variableName << kMarkerEnd;
+    std::string searchString = searchStringBuilder.str();
+    angle::ReplaceSubstring(shaderString, searchString, replacementString);
 }
 
 }  // anonymous namespace
@@ -100,15 +122,19 @@ gl::LinkResult GlslangWrapper::linkProgram(const gl::Context *glContext,
     // TODO(jmadill): Also do the same for ESSL 3 fragment outputs.
     for (const auto &attribute : programState.getAttributes())
     {
-        if (!attribute.staticUse)
+        if (!attribute.active)
+        {
+            InsertQualifierSpecifierString(&vertexSource, attribute.name, "");
             continue;
+        }
 
         std::string locationString = "location = " + Str(attribute.location);
         InsertLayoutSpecifierString(&vertexSource, attribute.name, locationString);
+        InsertQualifierSpecifierString(&vertexSource, attribute.name, "in");
     }
 
     // Assign varying locations.
-    for (const auto &varyingReg : resources.varyingPacking.getRegisterList())
+    for (const gl::PackedVaryingRegister &varyingReg : resources.varyingPacking.getRegisterList())
     {
         const auto &varying        = *varyingReg.packedVarying;
 
@@ -116,6 +142,19 @@ gl::LinkResult GlslangWrapper::linkProgram(const gl::Context *glContext,
                                      ", component = " + Str(varyingReg.registerColumn);
         InsertLayoutSpecifierString(&vertexSource, varying.varying->name, locationString);
         InsertLayoutSpecifierString(&fragmentSource, varying.varying->name, locationString);
+
+        ASSERT(varying.interpolation == sh::INTERPOLATION_SMOOTH);
+        InsertQualifierSpecifierString(&vertexSource, varying.varying->name, "out");
+        InsertQualifierSpecifierString(&fragmentSource, varying.varying->name, "in");
+    }
+
+    // Remove all the markers for unused varyings.
+    for (const std::string &varyingName : resources.varyingPacking.getInactiveVaryingNames())
+    {
+        InsertLayoutSpecifierString(&vertexSource, varyingName, "");
+        InsertLayoutSpecifierString(&fragmentSource, varyingName, "");
+        InsertQualifierSpecifierString(&vertexSource, varyingName, "");
+        InsertQualifierSpecifierString(&fragmentSource, varyingName, "");
     }
 
     // Bind the default uniforms for vertex and fragment shaders.
@@ -144,18 +183,27 @@ gl::LinkResult GlslangWrapper::linkProgram(const gl::Context *glContext,
         if (samplerUniform.isActive(gl::ShaderType::Vertex))
         {
             InsertLayoutSpecifierString(&vertexSource, samplerUniform.name, setBindingString);
+            InsertQualifierSpecifierString(&vertexSource, samplerUniform.name, kUniformQualifier);
+        }
+        else
+        {
+            InsertQualifierSpecifierString(&vertexSource, samplerUniform.name, "");
         }
 
         if (samplerUniform.isActive(gl::ShaderType::Fragment))
         {
             InsertLayoutSpecifierString(&fragmentSource, samplerUniform.name, setBindingString);
+            InsertQualifierSpecifierString(&fragmentSource, samplerUniform.name, kUniformQualifier);
+        }
+        else
+        {
+            InsertQualifierSpecifierString(&fragmentSource, samplerUniform.name, "");
         }
 
         textureCount += samplerUniform.getBasicTypeElementCount();
     }
 
     std::array<const char *, 2> strings = {{vertexSource.c_str(), fragmentSource.c_str()}};
-
     std::array<int, 2> lengths = {
         {static_cast<int>(vertexSource.length()), static_cast<int>(fragmentSource.length())}};
 

src/tests/gl_tests/GLSLTest.cpp

@@ -928,10 +928,6 @@ TEST_P(GLSLTest, InvariantAllBoth)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnFloat)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "float f() { if (v_varying > 0.0) return 1.0; }\n"
@@ -944,10 +940,6 @@ TEST_P(GLSLTest, MissingReturnFloat)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnVec2)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "vec2 f() { if (v_varying > 0.0) return vec2(1.0, 1.0); }\n"
@@ -960,10 +952,6 @@ TEST_P(GLSLTest, MissingReturnVec2)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnVec3)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "vec3 f() { if (v_varying > 0.0) return vec3(1.0, 1.0, 1.0); }\n"
@@ -976,10 +964,6 @@ TEST_P(GLSLTest, MissingReturnVec3)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnVec4)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "vec4 f() { if (v_varying > 0.0) return vec4(1.0, 1.0, 1.0, 1.0); }\n"
@@ -992,10 +976,6 @@ TEST_P(GLSLTest, MissingReturnVec4)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnIVec4)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "ivec4 f() { if (v_varying > 0.0) return ivec4(1, 1, 1, 1); }\n"
@@ -1008,10 +988,6 @@ TEST_P(GLSLTest, MissingReturnIVec4)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnMat4)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "mat4 f() { if (v_varying > 0.0) return mat4(1.0); }\n"
@@ -1024,10 +1000,6 @@ TEST_P(GLSLTest, MissingReturnMat4)
 // Verify that functions without return statements still compile
 TEST_P(GLSLTest, MissingReturnStruct)
 {
-    // TODO(lucferron): Varyings that aren't used as an output in the FS are not yet supported.
-    // http://anglebug.com/2460
-    ANGLE_SKIP_TEST_IF(IsVulkan());
-
     const std::string vertexShaderSource =
         "varying float v_varying;\n"
         "struct s { float a; int b; vec2 c; };\n"