1 files changed, 63 insertions, 0 deletions
diff --git a/include/clang/AST/TypeOrdering.h b/include/clang/AST/TypeOrdering.h
new file mode 100644
index 0000000..4f60273
--- /dev/null
+++ b/include/clang/AST/TypeOrdering.h
@@ -0,0 +1,63 @@
+//===-------------- TypeOrdering.h - Total ordering for types -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file provides a function objects and specializations that
+//  allow QualType values to be sorted, used in std::maps, std::sets,
+//  llvm::DenseMaps, and llvm::DenseSets.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TYPE_ORDERING_H
+#define LLVM_CLANG_TYPE_ORDERING_H
+
+#include "clang/AST/Type.h"
+#include <functional>
+
+namespace clang {
+
+/// QualTypeOrdering - Function object that provides a total ordering
+/// on QualType values.
+struct QualTypeOrdering : std::binary_function<QualType, QualType, bool> {
+  bool operator()(QualType T1, QualType T2) const {
+    return std::less<void*>()(T1.getAsOpaquePtr(), T2.getAsOpaquePtr());
+  }
+};
+
+}
+
+namespace llvm {
+  template<class> struct DenseMapInfo;
+
+  template<> struct DenseMapInfo<clang::QualType> {
+    static inline clang::QualType getEmptyKey() { return clang::QualType(); }
+
+    static inline clang::QualType getTombstoneKey() { 
+      using clang::QualType;
+      return QualType::getFromOpaquePtr(reinterpret_cast<clang::Type *>(-1));
+    }
+
+    static unsigned getHashValue(clang::QualType Val) {
+      return (unsigned)((uintptr_t)Val.getAsOpaquePtr()) ^
+            ((unsigned)((uintptr_t)Val.getAsOpaquePtr() >> 9));
+    }
+
+    static bool isEqual(clang::QualType LHS, clang::QualType RHS) {
+      return LHS == RHS;
+    }
+
+    static bool isPod() { 
+      // QualType 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