Move GlobalDecl to its own file. Also add DenseMapInfo traits.

llvm-svn: 87081

1 files changed, 110 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/GlobalDecl.h b/clang/lib/CodeGen/GlobalDecl.h
new file mode 100644
index 00000000000..b812020f2aa
--- /dev/null
+++ b/clang/lib/CodeGen/GlobalDecl.h
@@ -0,0 +1,110 @@
+//===--- GlobalDecl.h - Global declaration holder ---------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// A GlobalDecl can hold either a regular variable/function or a C++ ctor/dtor
+// together with its type.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CLANG_CODEGEN_GLOBALDECL_H
+#define CLANG_CODEGEN_GLOBALDECL_H
+
+namespace clang {
+
+namespace CodeGen {
+
+/// GlobalDecl - represents a global declaration. This can either be a
+/// CXXConstructorDecl and the constructor type (Base, Complete).
+/// a CXXDestructorDecl and the destructor type (Base, Complete) or
+/// a VarDecl, a FunctionDecl or a BlockDecl.
+class GlobalDecl {
+  llvm::PointerIntPair<const Decl*, 2> Value;
+
+  void Init(const Decl *D) {
+    assert(!isa<CXXConstructorDecl>(D) && "Use other ctor with ctor decls!");
+    assert(!isa<CXXDestructorDecl>(D) && "Use other ctor with dtor decls!");
+
+    Value.setPointer(D);
+  }
+  
+public:
+  GlobalDecl() {}
+
+  GlobalDecl(const VarDecl *D) { Init(D);}
+  GlobalDecl(const FunctionDecl *D) { Init(D); }
+  GlobalDecl(const BlockDecl *D) { Init(D); }
+  GlobalDecl(const ObjCMethodDecl *D) { Init(D); }
+
+  GlobalDecl(const CXXConstructorDecl *D, CXXCtorType Type)
+  : Value(D, Type) {}
+  GlobalDecl(const CXXDestructorDecl *D, CXXDtorType Type)
+  : Value(D, Type) {}
+
+  const Decl *getDecl() const { return Value.getPointer(); }
+
+  CXXCtorType getCtorType() const {
+    assert(isa<CXXConstructorDecl>(getDecl()) && "Decl is not a ctor!");
+    return static_cast<CXXCtorType>(Value.getInt());
+  }
+
+  CXXDtorType getDtorType() const {
+    assert(isa<CXXDestructorDecl>(getDecl()) && "Decl is not a dtor!");
+    return static_cast<CXXDtorType>(Value.getInt());
+  }
+  
+  friend bool operator==(const GlobalDecl &LHS, const GlobalDecl &RHS) {
+    return LHS.Value == RHS.Value;
+  }
+  
+  void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }
+
+  static GlobalDecl getFromOpaquePtr(void *P) {
+    GlobalDecl GD;
+    GD.Value.setFromOpaqueValue(P);
+    return GD;
+  }
+};
+
+} // end namespace CodeGen
+} // end namespace clang
+
+namespace llvm {
+  template<class> struct DenseMapInfo;
+
+  template<> struct DenseMapInfo<clang::CodeGen::GlobalDecl> {
+    static inline clang::CodeGen::GlobalDecl getEmptyKey() {
+      return clang::CodeGen::GlobalDecl();
+    }
+  
+    static inline clang::CodeGen::GlobalDecl getTombstoneKey() {
+      return clang::CodeGen::GlobalDecl::
+        getFromOpaquePtr(reinterpret_cast<void*>(-1));
+    }
+
+    static unsigned getHashValue(clang::CodeGen::GlobalDecl GD) {
+      return DenseMapInfo<void*>::getHashValue(GD.getAsOpaquePtr());
+    }
+    
+    static bool isEqual(clang::CodeGen::GlobalDecl LHS, 
+                        clang::CodeGen::GlobalDecl RHS) {
+      return LHS == RHS;
+    }
+      
+    static bool isPod() {
+      // GlobalDecl isn't *technically* a POD type. However, we can get
+      // away with calling it a POD type since its copy constructor,
+      // copy assignment operator, and destructor are all trivial.
+      return true;
+    }
+      
+  };
+  
+}
+
+#endif