Replace VariableDecoration::(Is|As)Set with Castable

Change-Id: I9808e31f3842b70b3df9ed0398583e09e4f2ca42
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/34310
Reviewed-by: dan sinclair <dsinclair@chromium.org>

src/ast/binding_decoration_test.cc

@@ -35,7 +35,7 @@ TEST_F(BindingDecorationTest, Is) {
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
   EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(d->Is<LocationDecoration>());
-  EXPECT_FALSE(bd.IsSet());
+  EXPECT_FALSE(d->Is<SetDecoration>());
 }
 
 TEST_F(BindingDecorationTest, ToStr) {

src/ast/builtin_decoration_test.cc

@@ -35,7 +35,7 @@ TEST_F(BuiltinDecorationTest, Is) {
   EXPECT_TRUE(d->Is<BuiltinDecoration>());
   EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(d->Is<LocationDecoration>());
-  EXPECT_FALSE(bd.IsSet());
+  EXPECT_FALSE(d->Is<SetDecoration>());
 }
 
 TEST_F(BuiltinDecorationTest, ToStr) {

src/ast/constant_id_decoration_test.cc

@@ -34,7 +34,7 @@ TEST_F(ConstantIdDecorationTest, Is) {
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
   EXPECT_TRUE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(d->Is<LocationDecoration>());
-  EXPECT_FALSE(cd.IsSet());
+  EXPECT_FALSE(d->Is<SetDecoration>());
 }
 
 TEST_F(ConstantIdDecorationTest, ToStr) {

src/ast/location_decoration_test.cc

@@ -37,7 +37,7 @@ TEST_F(LocationDecorationTest, Is) {
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
   EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_TRUE(d->Is<LocationDecoration>());
-  EXPECT_FALSE(ld.IsSet());
+  EXPECT_FALSE(d->Is<SetDecoration>());
 }
 
 TEST_F(LocationDecorationTest, ToStr) {

src/ast/set_decoration.cc

@@ -22,10 +22,6 @@ SetDecoration::SetDecoration(uint32_t val, const Source& source)
 
 SetDecoration::~SetDecoration() = default;
 
-bool SetDecoration::IsSet() const {
-  return true;
-}
-
 void SetDecoration::to_str(std::ostream& out, size_t indent) const {
   make_indent(out, indent);
   out << "SetDecoration{" << value_ << "}" << std::endl;

src/ast/set_decoration.h

@@ -31,9 +31,6 @@ class SetDecoration : public Castable<SetDecoration, VariableDecoration> {
   SetDecoration(uint32_t value, const Source& source);
   ~SetDecoration() override;
 
-  /// @returns true if this is a set decoration
-  bool IsSet() const override;
-
   /// @returns the set value
   uint32_t value() const { return value_; }
 

src/ast/set_decoration_test.cc

@@ -35,7 +35,7 @@ TEST_F(SetDecorationTest, Is) {
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
   EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(d->Is<LocationDecoration>());
-  EXPECT_TRUE(sd.IsSet());
+  EXPECT_TRUE(d->Is<SetDecoration>());
 }
 
 TEST_F(SetDecorationTest, ToStr) {

src/ast/variable_decoration.cc

@@ -16,8 +16,6 @@
 
 #include <assert.h>
 
-#include "src/ast/set_decoration.h"
-
 namespace tint {
 namespace ast {
 
@@ -31,14 +29,5 @@ DecorationKind VariableDecoration::GetKind() const {
   return Kind;
 }
 
-bool VariableDecoration::IsSet() const {
-  return false;
-}
-
-SetDecoration* VariableDecoration::AsSet() {
-  assert(IsSet());
-  return static_cast<SetDecoration*>(this);
-}
-
 }  // namespace ast
 }  // namespace tint

src/ast/variable_decoration.h

@@ -25,8 +25,6 @@
 namespace tint {
 namespace ast {
 
-class SetDecoration;
-
 /// A decoration attached to a variable
 class VariableDecoration : public Castable<VariableDecoration, Decoration> {
  public:
@@ -38,12 +36,6 @@ class VariableDecoration : public Castable<VariableDecoration, Decoration> {
   /// @return the decoration kind
   DecorationKind GetKind() const override;
 
-  /// @returns true if this is a set decoration
-  virtual bool IsSet() const;
-
-  /// @returns the decoration as a set decoration
-  SetDecoration* AsSet();
-
  protected:
   /// Constructor
   /// @param source the source of this decoration