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

Change-Id: I3f402fe8925ef7d5c9b3d5b21f2556d7af59a0cd
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/34308
Reviewed-by: dan sinclair <dsinclair@chromium.org>

src/ast/binding_decoration_test.cc

@@ -15,6 +15,7 @@
 #include "src/ast/binding_decoration.h"
 
 #include "src/ast/test_helper.h"
+#include "src/ast/constant_id_decoration.h"
 
 namespace tint {
 namespace ast {
@@ -32,7 +33,7 @@ TEST_F(BindingDecorationTest, Is) {
   Decoration* d = &bd;
   EXPECT_TRUE(d->Is<BindingDecoration>());
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
-  EXPECT_FALSE(bd.IsConstantId());
+  EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(bd.IsLocation());
   EXPECT_FALSE(bd.IsSet());
 }

src/ast/builtin_decoration_test.cc

@@ -14,6 +14,7 @@
 
 #include "src/ast/builtin_decoration.h"
 
+#include "src/ast/constant_id_decoration.h"
 #include "src/ast/test_helper.h"
 
 namespace tint {
@@ -32,7 +33,7 @@ TEST_F(BuiltinDecorationTest, Is) {
   Decoration* d = &bd;
   EXPECT_FALSE(d->Is<BindingDecoration>());
   EXPECT_TRUE(d->Is<BuiltinDecoration>());
-  EXPECT_FALSE(bd.IsConstantId());
+  EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(bd.IsLocation());
   EXPECT_FALSE(bd.IsSet());
 }

src/ast/constant_id_decoration.cc

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

src/ast/constant_id_decoration.h

@@ -31,9 +31,6 @@ class ConstantIdDecoration
   ConstantIdDecoration(uint32_t val, const Source& source);
   ~ConstantIdDecoration() override;
 
-  /// @returns true if this is a constant_id decoration
-  bool IsConstantId() const override;
-
   /// @returns the constant id value
   uint32_t value() const { return value_; }
 

src/ast/constant_id_decoration_test.cc

@@ -32,7 +32,7 @@ TEST_F(ConstantIdDecorationTest, Is) {
   Decoration* d = &cd;
   EXPECT_FALSE(d->Is<BindingDecoration>());
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
-  EXPECT_TRUE(cd.IsConstantId());
+  EXPECT_TRUE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(cd.IsLocation());
   EXPECT_FALSE(cd.IsSet());
 }

src/ast/decorated_variable.cc

@@ -51,7 +51,7 @@ bool DecoratedVariable::HasBuiltinDecoration() const {
 
 bool DecoratedVariable::HasConstantIdDecoration() const {
   for (auto* deco : decorations_) {
-    if (deco->IsConstantId()) {
+    if (deco->Is<ConstantIdDecoration>()) {
       return true;
     }
   }
@@ -61,8 +61,8 @@ bool DecoratedVariable::HasConstantIdDecoration() const {
 uint32_t DecoratedVariable::constant_id() const {
   assert(HasConstantIdDecoration());
   for (auto* deco : decorations_) {
-    if (deco->IsConstantId()) {
-      return deco->AsConstantId()->value();
+    if (auto* cid = deco->As<ConstantIdDecoration>()) {
+      return cid->value();
     }
   }
   return 0;

src/ast/location_decoration_test.cc

@@ -16,6 +16,7 @@
 
 #include <sstream>
 
+#include "src/ast/constant_id_decoration.h"
 #include "src/ast/test_helper.h"
 
 namespace tint {
@@ -34,7 +35,7 @@ TEST_F(LocationDecorationTest, Is) {
   Decoration* d = &ld;
   EXPECT_FALSE(d->Is<BindingDecoration>());
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
-  EXPECT_FALSE(ld.IsConstantId());
+  EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_TRUE(ld.IsLocation());
   EXPECT_FALSE(ld.IsSet());
 }

src/ast/set_decoration_test.cc

@@ -14,6 +14,7 @@
 
 #include "src/ast/set_decoration.h"
 
+#include "src/ast/constant_id_decoration.h"
 #include "src/ast/test_helper.h"
 
 namespace tint {
@@ -32,7 +33,7 @@ TEST_F(SetDecorationTest, Is) {
   Decoration* d = &sd;
   EXPECT_FALSE(d->Is<BindingDecoration>());
   EXPECT_FALSE(d->Is<BuiltinDecoration>());
-  EXPECT_FALSE(sd.IsConstantId());
+  EXPECT_FALSE(d->Is<ConstantIdDecoration>());
   EXPECT_FALSE(sd.IsLocation());
   EXPECT_TRUE(sd.IsSet());
 }

src/ast/variable_decoration.cc

@@ -16,9 +16,6 @@
 
 #include <assert.h>
 
-#include "src/ast/binding_decoration.h"
-#include "src/ast/builtin_decoration.h"
-#include "src/ast/constant_id_decoration.h"
 #include "src/ast/location_decoration.h"
 #include "src/ast/set_decoration.h"
 
@@ -39,19 +36,10 @@ bool VariableDecoration::IsLocation() const {
   return false;
 }
 
-bool VariableDecoration::IsConstantId() const {
-  return false;
-}
-
 bool VariableDecoration::IsSet() const {
   return false;
 }
 
-ConstantIdDecoration* VariableDecoration::AsConstantId() {
-  assert(IsConstantId());
-  return static_cast<ConstantIdDecoration*>(this);
-}
-
 LocationDecoration* VariableDecoration::AsLocation() {
   assert(IsLocation());
   return static_cast<LocationDecoration*>(this);

src/ast/variable_decoration.h

@@ -40,15 +40,11 @@ class VariableDecoration : public Castable<VariableDecoration, Decoration> {
   /// @return the decoration kind
   DecorationKind GetKind() const override;
 
-  /// @returns true if this is a constant id decoration
-  virtual bool IsConstantId() const;
   /// @returns true if this is a location decoration
   virtual bool IsLocation() const;
   /// @returns true if this is a set decoration
   virtual bool IsSet() const;
 
-  /// @returns the decoration as a constant id decoration
-  ConstantIdDecoration* AsConstantId();
   /// @returns the decoration as a location decoration
   LocationDecoration* AsLocation();
   /// @returns the decoration as a set decoration