Remove predefined precision qualifiers from ESSL3 samplers

src/compiler/translator/Compiler.cpp

@@ -423,11 +423,6 @@ bool TCompiler::InitBuiltInSymbolTable(const ShBuiltInResources &resources)
     floatingPoint.secondarySize = 1;
     floatingPoint.array = false;
 
-    TPublicType sampler;
-    sampler.primarySize = 1;
-    sampler.secondarySize = 1;
-    sampler.array = false;
-
     switch(shaderType)
     {
       case GL_FRAGMENT_SHADER:
@@ -440,14 +435,15 @@ bool TCompiler::InitBuiltInSymbolTable(const ShBuiltInResources &resources)
       default:
         assert(false && "Language not supported");
     }
-    // We set defaults for all the sampler types, even those that are
+    // Set defaults for sampler types that have default precision, even those that are
     // only available if an extension exists.
-    for (int samplerType = EbtGuardSamplerBegin + 1;
-         samplerType < EbtGuardSamplerEnd; ++samplerType)
-    {
-        sampler.type = static_cast<TBasicType>(samplerType);
-        symbolTable.setDefaultPrecision(sampler, EbpLow);
-    }
+    // New sampler types in ESSL3 don't have default precision. ESSL1 types do.
+    initSamplerDefaultPrecision(EbtSampler2D);
+    initSamplerDefaultPrecision(EbtSamplerCube);
+    // SamplerExternalOES is specified in the extension to have default precision.
+    initSamplerDefaultPrecision(EbtSamplerExternalOES);
+    // It isn't specified whether Sampler2DRect has default precision.
+    initSamplerDefaultPrecision(EbtSampler2DRect);
 
     InsertBuiltInFunctions(shaderType, shaderSpec, resources, symbolTable);
 
@@ -456,6 +452,17 @@ bool TCompiler::InitBuiltInSymbolTable(const ShBuiltInResources &resources)
     return true;
 }
 
+void TCompiler::initSamplerDefaultPrecision(TBasicType samplerType)
+{
+    ASSERT(samplerType > EbtGuardSamplerBegin && samplerType < EbtGuardSamplerEnd);
+    TPublicType sampler;
+    sampler.primarySize   = 1;
+    sampler.secondarySize = 1;
+    sampler.array         = false;
+    sampler.type          = samplerType;
+    symbolTable.setDefaultPrecision(sampler, EbpLow);
+}
+
 void TCompiler::setResourceString()
 {
     std::ostringstream strstream;

src/compiler/translator/Compiler.h

@@ -179,6 +179,8 @@ class TCompiler : public TShHandleBase
     bool tagUsedFunctions();
     void internalTagUsedFunction(size_t index);
 
+    void initSamplerDefaultPrecision(TBasicType samplerType);
+
     // Removes unused function declarations and prototypes from the AST
     class UnusedPredicate;
     bool pruneUnusedFunctions(TIntermNode *root);

src/compiler/translator/ParseContext.cpp

@@ -226,24 +226,25 @@ bool TParseContext::precisionErrorCheck(const TSourceLoc &line,
 {
     if (!mChecksPrecisionErrors)
         return false;
-    switch (type)
+    if (precision == EbpUndefined)
     {
-        case EbtFloat:
-            if (precision == EbpUndefined)
-            {
+        switch (type)
+        {
+            case EbtFloat:
                 error(line, "No precision specified for (float)", "");
                 return true;
-            }
-            break;
-        case EbtInt:
-            if (precision == EbpUndefined)
-            {
+            case EbtInt:
+            case EbtUInt:
+                UNREACHABLE();  // there's always a predeclared qualifier
                 error(line, "No precision specified (int)", "");
                 return true;
-            }
-            break;
-        default:
-            return false;
+            default:
+                if (IsSampler(type))
+                {
+                    error(line, "No precision specified (sampler)", "");
+                    return true;
+                }
+        }
     }
     return false;
 }

src/compiler/translator/SymbolTable.cpp

@@ -280,7 +280,7 @@ TPrecision TSymbolTable::getDefaultPrecision(TBasicType type) const
 
     int level = static_cast<int>(precisionStack.size()) - 1;
     assert(level >= 0); // Just to be safe. Should not happen.
-    // If we dont find anything we return this. Should we error check this?
+    // If we dont find anything we return this. Some types don't have predefined default precision.
     TPrecision prec = EbpUndefined;
     while (level >= 0)
     {

src/tests/compiler_tests/MalformedShader_test.cpp

@@ -1334,3 +1334,22 @@ TEST_F(MalformedShaderTest, DefaultPrecisionUint)
         FAIL() << "Shader compilation succeeded, expecting failure " << mInfoLog;
     }
 }
+
+// Test that sampler3D needs to be precision qualified.
+// ESSL 3.00.4 section 4.5.4: New ESSL 3.00 sampler types don't have predefined precision.
+TEST_F(MalformedShaderTest, NoPrecisionSampler3D)
+{
+    const std::string &shaderString =
+        "#version 300 es\n"
+        "precision mediump float;\n"
+        "uniform sampler3D s;\n"
+        "out vec4 my_FragColor;\n"
+        "void main()\n"
+        "{\n"
+        "   my_FragColor = vec4(0.0);\n"
+        "}\n";
+    if (compile(shaderString))
+    {
+        FAIL() << "Shader compilation succeeded, expecting failure " << mInfoLog;
+    }
+}

src/tests/gl_tests/MipmapTest.cpp

@@ -265,7 +265,7 @@ class MipmapTestES3 : public ANGLETest
         const std::string fragmentShaderSourceArray = SHADER_SOURCE
         (   #version 300 es\n
             precision highp float;
-            uniform sampler2DArray tex;
+            uniform highp sampler2DArray tex;
             uniform int slice;
             in vec2 texcoord;
             out vec4 out_FragColor;
@@ -303,7 +303,7 @@ class MipmapTestES3 : public ANGLETest
         const std::string fragmentShaderSource3D = SHADER_SOURCE
         (   #version 300 es\n
             precision highp float;
-            uniform sampler3D tex;
+            uniform highp sampler3D tex;
             uniform float slice;
             uniform float lod;
             in vec2 texcoord;

src/tests/gl_tests/TextureTest.cpp

@@ -278,7 +278,7 @@ class TextureTestES3 : public ANGLETest
         const std::string fragmentShaderSource2DArray =
             "#version 300 es\n"
             "precision highp float;\n"
-            "uniform sampler2DArray tex2DArray;\n"
+            "uniform highp sampler2DArray tex2DArray;\n"
             "in vec2 texcoord;\n"
             "out vec4 fragColor;\n"
             "void main()\n"