Fix asserts related to writing nameless parameters in HLSL

src/compiler/translator/Symbol.cpp

@@ -46,11 +46,13 @@ TSymbol::TSymbol(TSymbolTable *symbolTable,
 
 ImmutableString TSymbol::name() const
 {
-    if (mName != "")
+    if (!mName.empty())
     {
         return mName;
     }
-    ASSERT(mSymbolType == SymbolType::AngleInternal);
+    // This can be called for nameless function parameters in HLSL.
+    ASSERT(mSymbolType == SymbolType::AngleInternal ||
+           (mSymbolType == SymbolType::Empty && isVariable()));
     int uniqueId = mUniqueId.get();
     ImmutableStringBuilder symbolNameOut(sizeof(uniqueId) * 2u + 1u);
     symbolNameOut << 's';

src/compiler/translator/Symbol.h

@@ -42,8 +42,10 @@ class TSymbol : angle::NonCopyable
     // either statically allocated or pool allocated.
     ~TSymbol() = default;
 
-    // Don't call name() or getMangledName() for empty symbols (symbolType == SymbolType::Empty).
+    // Calling name() for empty symbols (symbolType == SymbolType::Empty) generates a similar name
+    // as for internal variables.
     ImmutableString name() const;
+    // Don't call getMangledName() for empty symbols (symbolType == SymbolType::Empty).
     virtual ImmutableString getMangledName() const;
 
     virtual bool isFunction() const { return false; }

src/compiler/translator/UtilsHLSL.cpp

@@ -829,8 +829,10 @@ TString Decorate(const ImmutableString &string)
 
 TString DecorateVariableIfNeeded(const TVariable &variable)
 {
-    if (variable.symbolType() == SymbolType::AngleInternal)
+    if (variable.symbolType() == SymbolType::AngleInternal ||
+        variable.symbolType() == SymbolType::Empty)
     {
+        // Besides handling internal variables, we generate names for nameless parameters here.
         const ImmutableString &name = variable.name();
         // The name should not have a prefix reserved for user-defined variables or functions.
         ASSERT(!name.beginsWith("f_"));

src/tests/compiler_tests/HLSLOutput_test.cpp

@@ -156,3 +156,22 @@ TEST_F(HLSLOutputTest, ArrayReturnValue)
         })";
     compile(shaderString);
 }
+
+// Test that writing parameters without a name doesn't assert.
+TEST_F(HLSLOutputTest, ParameterWithNoName)
+{
+    const std::string &shaderString =
+        R"(precision mediump float;
+
+        uniform vec4 v;
+
+        vec4 s(vec4)
+        {
+            return v;
+        }
+        void main()
+        {
+            gl_FragColor = s(v);
+        })";
+    compile(shaderString);
+}