Replace Variable::(Is|As)* with Castable

Change-Id: I7a49287af079d53cee095fa2243dd21757546b56
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/34318
Reviewed-by: dan sinclair <dsinclair@chromium.org>

src/ast/decorated_variable.cc

@@ -69,10 +69,6 @@ uint32_t DecoratedVariable::constant_id() const {
   return 0;
 }
 
-bool DecoratedVariable::IsDecorated() const {
-  return true;
-}
-
 bool DecoratedVariable::IsValid() const {
   return Variable::IsValid();
 }

src/ast/decorated_variable.h

@@ -56,9 +56,6 @@ class DecoratedVariable : public Castable<DecoratedVariable, Variable> {
   /// |HasConstantIdDecoration| has been called first.
   uint32_t constant_id() const;
 
-  /// @returns true if this is a decorated variable
-  bool IsDecorated() const override;
-
   /// @returns true if the name and path are both present
   bool IsValid() const override;
 

src/ast/decorated_variable_test.cc

@@ -108,7 +108,7 @@ TEST_F(DecoratedVariableTest, IsValid) {
 
 TEST_F(DecoratedVariableTest, IsDecorated) {
   DecoratedVariable dv;
-  EXPECT_TRUE(dv.IsDecorated());
+  EXPECT_TRUE(dv.Is<ast::DecoratedVariable>());
 }
 
 TEST_F(DecoratedVariableTest, to_str) {

src/ast/function.cc

@@ -85,13 +85,12 @@ Function::referenced_location_variables() const {
   std::vector<std::pair<Variable*, LocationDecoration*>> ret;
 
   for (auto* var : referenced_module_variables()) {
-    if (!var->IsDecorated()) {
-      continue;
-    }
-    for (auto* deco : var->AsDecorated()->decorations()) {
-      if (auto* location = deco->As<LocationDecoration>()) {
-        ret.push_back({var, location});
-        break;
+    if (auto* decos = var->As<ast::DecoratedVariable>()) {
+      for (auto* deco : decos->decorations()) {
+        if (auto* location = deco->As<LocationDecoration>()) {
+          ret.push_back({var, location});
+          break;
+        }
       }
     }
   }
@@ -103,14 +102,14 @@ Function::referenced_uniform_variables() const {
   std::vector<std::pair<Variable*, Function::BindingInfo>> ret;
 
   for (auto* var : referenced_module_variables()) {
-    if (!var->IsDecorated() ||
+    if (!var->Is<ast::DecoratedVariable>() ||
         var->storage_class() != ast::StorageClass::kUniform) {
       continue;
     }
 
     BindingDecoration* binding = nullptr;
     SetDecoration* set = nullptr;
-    for (auto* deco : var->AsDecorated()->decorations()) {
+    for (auto* deco : var->As<ast::DecoratedVariable>()->decorations()) {
       if (auto* b = deco->As<ast::BindingDecoration>()) {
         binding = b;
       } else if (auto* s = deco->As<ast::SetDecoration>()) {
@@ -131,14 +130,14 @@ Function::referenced_storagebuffer_variables() const {
   std::vector<std::pair<Variable*, Function::BindingInfo>> ret;
 
   for (auto* var : referenced_module_variables()) {
-    if (!var->IsDecorated() ||
+    if (!var->Is<ast::DecoratedVariable>() ||
         var->storage_class() != ast::StorageClass::kStorageBuffer) {
       continue;
     }
 
     BindingDecoration* binding = nullptr;
     SetDecoration* set = nullptr;
-    for (auto* deco : var->AsDecorated()->decorations()) {
+    for (auto* deco : var->As<ast::DecoratedVariable>()->decorations()) {
       if (auto* b = deco->As<ast::BindingDecoration>()) {
         binding = b;
       } else if (auto* s = deco->As<ast::SetDecoration>()) {
@@ -159,10 +158,10 @@ Function::referenced_builtin_variables() const {
   std::vector<std::pair<Variable*, BuiltinDecoration*>> ret;
 
   for (auto* var : referenced_module_variables()) {
-    if (!var->IsDecorated()) {
+    if (!var->Is<ast::DecoratedVariable>()) {
       continue;
     }
-    for (auto* deco : var->AsDecorated()->decorations()) {
+    for (auto* deco : var->As<ast::DecoratedVariable>()->decorations()) {
       if (auto* builtin = deco->As<BuiltinDecoration>()) {
         ret.push_back({var, builtin});
         break;
@@ -283,14 +282,15 @@ Function::ReferencedSamplerVariablesImpl(type::SamplerKind kind) const {
 
   for (auto* var : referenced_module_variables()) {
     auto* unwrapped_type = var->type()->UnwrapIfNeeded();
-    if (!var->IsDecorated() || !unwrapped_type->Is<ast::type::SamplerType>() ||
+    if (!var->Is<ast::DecoratedVariable>() ||
+        !unwrapped_type->Is<ast::type::SamplerType>() ||
         unwrapped_type->As<ast::type::SamplerType>()->kind() != kind) {
       continue;
     }
 
     BindingDecoration* binding = nullptr;
     SetDecoration* set = nullptr;
-    for (auto* deco : var->AsDecorated()->decorations()) {
+    for (auto* deco : var->As<ast::DecoratedVariable>()->decorations()) {
       if (auto* b = deco->As<ast::BindingDecoration>()) {
         binding = b;
       } else if (auto* s = deco->As<ast::SetDecoration>()) {
@@ -312,7 +312,8 @@ Function::ReferencedSampledTextureVariablesImpl(bool multisampled) const {
 
   for (auto* var : referenced_module_variables()) {
     auto* unwrapped_type = var->type()->UnwrapIfNeeded();
-    if (!var->IsDecorated() || !unwrapped_type->Is<ast::type::TextureType>()) {
+    if (!var->Is<ast::DecoratedVariable>() ||
+        !unwrapped_type->Is<ast::type::TextureType>()) {
       continue;
     }
 
@@ -325,7 +326,7 @@ Function::ReferencedSampledTextureVariablesImpl(bool multisampled) const {
 
     BindingDecoration* binding = nullptr;
     SetDecoration* set = nullptr;
-    for (auto* deco : var->AsDecorated()->decorations()) {
+    for (auto* deco : var->As<ast::DecoratedVariable>()->decorations()) {
       if (auto* b = deco->As<ast::BindingDecoration>()) {
         binding = b;
       } else if (auto* s = deco->As<ast::SetDecoration>()) {

src/ast/variable.cc

@@ -36,20 +36,6 @@ Variable::Variable(Variable&&) = default;
 
 Variable::~Variable() = default;
 
-DecoratedVariable* Variable::AsDecorated() {
-  assert(IsDecorated());
-  return static_cast<DecoratedVariable*>(this);
-}
-
-const DecoratedVariable* Variable::AsDecorated() const {
-  assert(IsDecorated());
-  return static_cast<const DecoratedVariable*>(this);
-}
-
-bool Variable::IsDecorated() const {
-  return false;
-}
-
 bool Variable::IsValid() const {
   if (name_.length() == 0) {
     return false;

src/ast/variable.h

@@ -29,8 +29,6 @@
 namespace tint {
 namespace ast {
 
-class DecoratedVariable;
-
 /// A Variable statement.
 ///
 /// An instance of this class represents one of three constructs in WGSL: "var"
@@ -134,14 +132,6 @@ class Variable : public Castable<Variable, Node> {
   /// @returns true if this is a constant, false otherwise
   bool is_const() const { return is_const_; }
 
-  /// @returns true if this is a decorated variable
-  virtual bool IsDecorated() const;
-
-  /// @returns the expression as a decorated variable
-  DecoratedVariable* AsDecorated();
-  /// @returns the expression as a decorated variable
-  const DecoratedVariable* AsDecorated() const;
-
   /// @returns true if the name and path are both present
   bool IsValid() const override;