support for type alias

1 files changed, 62 insertions, 0 deletions

diff --git a/TypeIdentifier.hh b/TypeIdentifier.hh
new file mode 100644
index 0000000..c939dcc
--- /dev/null
+++ b/TypeIdentifier.hh
@@ -0,0 +1,62 @@
+#ifndef PCC_TYPEIDENTIFIER_HH
+#define PCC_TYPEIDENTIFIER_HH
+
+#include "Context.hh"
+#include "Type.hh"
+
+namespace pcc {
+
+// since TypeAlias returns std::shared_ptr<Type> instead of llvm::Value*, we
+// won't use CodeGen() override.
+class TypeIdentifier {
+  public:
+    TypeIdentifier(Context* context, std::shared_ptr<Type> type = nullptr);
+    virtual std::shared_ptr<Type> GetType() = 0;
+
+  protected:
+    Context* context_;
+    std::shared_ptr<Type> type_;
+};
+
+class TrivialTypeIdentifier : public TypeIdentifier {
+  public:
+    TrivialTypeIdentifier(Context* context, std::shared_ptr<Type> type);
+    virtual std::shared_ptr<Type> GetType() override;
+};
+
+class AliasTypeIdentifier : public TypeIdentifier {
+  public:
+    AliasTypeIdentifier(Context* context, std::string&& alias);
+    virtual std::shared_ptr<Type> GetType() override;
+
+  protected:
+    std::string alias_;
+};
+
+// for pointers and arrays, so that we can create pointers to other alias type
+class PointerTypeIdentifier : public TypeIdentifier {
+  public:
+    PointerTypeIdentifier(Context* context,
+                          std::shared_ptr<TypeIdentifier> ElementType);
+    virtual std::shared_ptr<Type> GetType() override;
+
+  protected:
+    std::shared_ptr<TypeIdentifier> ElementType_;
+};
+
+class ArrayTypeIdentifier : public TypeIdentifier {
+  public:
+    ArrayTypeIdentifier(Context* context,
+                        std::shared_ptr<TypeIdentifier> ElementType,
+                        std::shared_ptr<ExprNode> start,
+                        std::shared_ptr<ExprNode> end);
+    virtual std::shared_ptr<Type> GetType() override;
+
+  protected:
+    std::shared_ptr<TypeIdentifier> ElementType_;
+    std::shared_ptr<ExprNode> start_;
+    std::shared_ptr<ExprNode> end_;
+};
+} // namespace pcc
+
+#endif // !PCC_TYPEIDENTIFIER_HH