diff -r 000000000000 -r 6474c204b198 mfbt/TypedEnumBits.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mfbt/TypedEnumBits.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,182 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS allows using a typed enum as bit flags. */
+
+#ifndef mozilla_TypedEnumBits_h
+#define mozilla_TypedEnumBits_h
+
+#include "mozilla/IntegerTypeTraits.h"
+#include "mozilla/TypedEnumInternal.h"
+
+namespace mozilla {
+
+#define MOZ_CASTABLETYPEDENUMRESULT_BINOP(Op, OtherType, ReturnType) \
+template<typename E> \
+MOZ_CONSTEXPR ReturnType \
+operator Op(const OtherType& e, const CastableTypedEnumResult<E>& r) \
+{ \
+  return ReturnType(e Op OtherType(r)); \
+} \
+template<typename E> \
+MOZ_CONSTEXPR ReturnType \
+operator Op(const CastableTypedEnumResult<E>& r, const OtherType& e) \
+{ \
+  return ReturnType(OtherType(r) Op e); \
+} \
+template<typename E> \
+MOZ_CONSTEXPR ReturnType \
+operator Op(const CastableTypedEnumResult<E>& r1, \
+            const CastableTypedEnumResult<E>& r2) \
+{ \
+  return ReturnType(OtherType(r1) Op OtherType(r2)); \
+}
+
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(|, E, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(&, E, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(^, E, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(==, E, bool)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(!=, E, bool)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(||, bool, bool)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP(&&, bool, bool)
+
+template <typename E>
+MOZ_CONSTEXPR CastableTypedEnumResult<E>
+operator ~(const CastableTypedEnumResult<E>& r)
+{
+  return CastableTypedEnumResult<E>(~(E(r)));
+}
+
+#define MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(Op) \
+template<typename E> \
+E& \
+operator Op(E& r1, \
+            const CastableTypedEnumResult<E>& r2) \
+{ \
+  return r1 Op E(r2); \
+}
+
+MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(&=)
+MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(|=)
+MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(^=)
+
+#undef MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP
+
+#undef MOZ_CASTABLETYPEDENUMRESULT_BINOP
+
+#ifndef MOZ_HAVE_CXX11_STRONG_ENUMS
+
+#define MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(Op, ReturnType) \
+template<typename E> \
+MOZ_CONSTEXPR ReturnType \
+operator Op(typename E::Enum e, const CastableTypedEnumResult<E>& r) \
+{ \
+  return ReturnType(e Op E(r)); \
+} \
+template<typename E> \
+MOZ_CONSTEXPR ReturnType \
+operator Op(const CastableTypedEnumResult<E>& r, typename E::Enum e) \
+{ \
+  return ReturnType(E(r) Op e); \
+}
+
+MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(|, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(&, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(^, CastableTypedEnumResult<E>)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(==, bool)
+MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11(!=, bool)
+
+#undef MOZ_CASTABLETYPEDENUMRESULT_BINOP_EXTRA_NON_CXX11
+
+#endif // not MOZ_HAVE_CXX11_STRONG_ENUMS
+
+namespace detail {
+template<typename E>
+struct UnsignedIntegerTypeForEnum
+  : UnsignedStdintTypeForSize<sizeof(E)>
+{};
+}
+
+} // namespace mozilla
+
+#define MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, Op) \
+   inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+   operator Op(Name a, Name b) \
+   { \
+     typedef mozilla::CastableTypedEnumResult<Name> Result; \
+     typedef mozilla::detail::UnsignedIntegerTypeForEnum<Name>::Type U; \
+     return Result(Name(U(a) Op U(b))); \
+   } \
+ \
+   inline Name& \
+   operator Op##=(Name& a, Name b) \
+   { \
+     return a = a Op b; \
+   }
+
+#define MOZ_MAKE_ENUM_CLASS_OPS_IMPL(Name) \
+   MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, |) \
+   MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, &) \
+   MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, ^) \
+   inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+   operator~(Name a) \
+   { \
+     typedef mozilla::CastableTypedEnumResult<Name> Result; \
+     typedef mozilla::detail::UnsignedIntegerTypeForEnum<Name>::Type U; \
+     return Result(Name(~(U(a)))); \
+   }
+
+#ifndef MOZ_HAVE_CXX11_STRONG_ENUMS
+#  define MOZ_MAKE_ENUM_CLASS_BITWISE_BINOP_EXTRA_NON_CXX11(Name, Op) \
+     inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+     operator Op(Name a, Name::Enum b) \
+     { \
+       return a Op Name(b); \
+     } \
+ \
+     inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+     operator Op(Name::Enum a, Name b) \
+     { \
+       return Name(a) Op b; \
+     } \
+ \
+     inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+     operator Op(Name::Enum a, Name::Enum b) \
+     { \
+       return Name(a) Op Name(b); \
+     } \
+ \
+     inline Name& \
+     operator Op##=(Name& a, Name::Enum b) \
+     { \
+       return a = a Op Name(b); \
+    }
+
+#  define MOZ_MAKE_ENUM_CLASS_OPS_EXTRA_NON_CXX11(Name) \
+     MOZ_MAKE_ENUM_CLASS_BITWISE_BINOP_EXTRA_NON_CXX11(Name, |) \
+     MOZ_MAKE_ENUM_CLASS_BITWISE_BINOP_EXTRA_NON_CXX11(Name, &) \
+     MOZ_MAKE_ENUM_CLASS_BITWISE_BINOP_EXTRA_NON_CXX11(Name, ^) \
+     inline MOZ_CONSTEXPR mozilla::CastableTypedEnumResult<Name> \
+     operator~(Name::Enum a) \
+     { \
+       return ~(Name(a)); \
+     }
+#endif
+
+/**
+ * MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS generates standard bitwise operators
+ * for the given enum type. Use this to enable using an enum type as bit-field.
+ */
+#ifdef MOZ_HAVE_CXX11_STRONG_ENUMS
+#  define MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Name) \
+     MOZ_MAKE_ENUM_CLASS_OPS_IMPL(Name)
+#else
+#  define MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Name) \
+     MOZ_MAKE_ENUM_CLASS_OPS_IMPL(Name) \
+     MOZ_MAKE_ENUM_CLASS_OPS_EXTRA_NON_CXX11(Name)
+#endif
+
+#endif // mozilla_TypedEnumBits_h