Add a constexpr constructor for TVariable

src/common/angleutils.h

@@ -30,7 +30,7 @@ using Microsoft::WRL::ComPtr;
 class NonCopyable
 {
   protected:
-    NonCopyable() = default;
+    constexpr NonCopyable() = default;
     ~NonCopyable() = default;
 
   private:

src/compiler/translator/ImmutableString.h

@@ -54,7 +54,8 @@ class ImmutableString
     {
     }
 
-    ImmutableString(const ImmutableString &) = default;
+    constexpr ImmutableString(const ImmutableString &) = default;
+
     ImmutableString &operator=(const ImmutableString &) = default;
 
     constexpr const char *data() const { return mData ? mData : ""; }

src/compiler/translator/Symbol.cpp

@@ -144,11 +144,6 @@ TFunction::TFunction(TSymbolTable *symbolTable,
     ASSERT(name != nullptr || symbolType == SymbolType::AngleInternal || tOp != EOpNull);
 }
 
-TFunction::~TFunction()
-{
-    // Just here to discourage the compiler from inlining it.
-}
-
 void TFunction::clearParameters()
 {
     parameters.clear();

src/compiler/translator/Symbol.h

@@ -38,10 +38,9 @@ class TSymbol : angle::NonCopyable
             SymbolType symbolType,
             TExtension extension = TExtension::UNDEFINED);
 
-    virtual ~TSymbol()
-    {
-        // don't delete name, it's from the pool
-    }
+    // Note that we don't have a virtual destructor in order to support constexpr symbols. Data is
+    // either statically allocated or pool allocated.
+    ~TSymbol() = default;
 
     // Don't call name() or getMangledName() for empty symbols (symbolType == SymbolType::Empty).
     ImmutableString name() const;
@@ -56,6 +55,14 @@ class TSymbol : angle::NonCopyable
     TExtension extension() const { return mExtension; }
 
   protected:
+    constexpr TSymbol(const TSymbolUniqueId &id,
+                      const ImmutableString &name,
+                      SymbolType symbolType,
+                      TExtension extension)
+        : mName(name), mUniqueId(id), mSymbolType(symbolType), mExtension(extension)
+    {
+    }
+
     const ImmutableString mName;
 
   private:
@@ -75,7 +82,6 @@ class TVariable : public TSymbol
               SymbolType symbolType,
               TExtension ext = TExtension::UNDEFINED);
 
-    ~TVariable() override {}
     bool isVariable() const override { return true; }
     const TType &getType() const { return *mType; }
 
@@ -84,6 +90,15 @@ class TVariable : public TSymbol
     void shareConstPointer(const TConstantUnion *constArray) { unionArray = constArray; }
 
   private:
+    constexpr TVariable(const TSymbolUniqueId &id,
+                        const ImmutableString &name,
+                        SymbolType symbolType,
+                        TExtension extension,
+                        const TType *type)
+        : TSymbol(id, name, symbolType, extension), mType(type), unionArray(nullptr)
+    {
+    }
+
     const TType *mType;
     const TConstantUnion *unionArray;
 };
@@ -190,8 +205,6 @@ class TFunction : public TSymbol
               TOperator tOp        = EOpNull,
               TExtension extension = TExtension::UNDEFINED);
 
-    virtual ~TFunction();
-
     bool isFunction() const override { return true; }
 
     void addParameter(const TConstParameter &p)

src/compiler/translator/SymbolUniqueId.cpp

@@ -20,7 +20,6 @@ TSymbolUniqueId::TSymbolUniqueId(const TSymbol &symbol) : mId(symbol.uniqueId().
 {
 }
 
-TSymbolUniqueId::TSymbolUniqueId(const TSymbolUniqueId &) = default;
 TSymbolUniqueId &TSymbolUniqueId::operator=(const TSymbolUniqueId &) = default;
 
 int TSymbolUniqueId::get() const

src/compiler/translator/SymbolUniqueId.h

@@ -22,13 +22,15 @@ class TSymbolUniqueId
     POOL_ALLOCATOR_NEW_DELETE();
     explicit TSymbolUniqueId(TSymbolTable *symbolTable);
     explicit TSymbolUniqueId(const TSymbol &symbol);
-    TSymbolUniqueId(const TSymbolUniqueId &);
+    constexpr TSymbolUniqueId(const TSymbolUniqueId &) = default;
     TSymbolUniqueId &operator=(const TSymbolUniqueId &);
     bool operator==(const TSymbolUniqueId &) const;
 
     int get() const;
 
   private:
+    constexpr TSymbolUniqueId(int staticId) : mId(staticId) {}
+
     int mId;
 };