+++ /dev/null
-/* Copyright (C) 2015-2019 Free Software Foundation, Inc.
-
- This file is part of GDB.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>. */
-
-#ifndef COMMON_ENUM_FLAGS_H
-#define COMMON_ENUM_FLAGS_H
-
-/* Type-safe wrapper for enum flags. enum flags are enums where the
- values are bits that are meant to be ORed together.
-
- This allows writing code like the below, while with raw enums this
- would fail to compile without casts to enum type at the assignments
- to 'f':
-
- enum some_flag
- {
- flag_val1 = 1 << 1,
- flag_val2 = 1 << 2,
- flag_val3 = 1 << 3,
- flag_val4 = 1 << 4,
- };
- DEF_ENUM_FLAGS_TYPE(enum some_flag, some_flags);
-
- some_flags f = flag_val1 | flag_val2;
- f |= flag_val3;
-
- It's also possible to assign literal zero to an enum flags variable
- (meaning, no flags), dispensing adding an awkward explicit "no
- value" value to the enumeration. For example:
-
- some_flags f = 0;
- f |= flag_val3 | flag_val4;
-
- Note that literal integers other than zero fail to compile:
-
- some_flags f = 1; // error
-*/
-
-#ifdef __cplusplus
-
-/* Traits type used to prevent the global operator overloads from
- instantiating for non-flag enums. */
-template<typename T> struct enum_flags_type {};
-
-/* Use this to mark an enum as flags enum. It defines FLAGS as
- enum_flags wrapper class for ENUM, and enables the global operator
- overloads for ENUM. */
-#define DEF_ENUM_FLAGS_TYPE(enum_type, flags_type) \
- typedef enum_flags<enum_type> flags_type; \
- template<> \
- struct enum_flags_type<enum_type> \
- { \
- typedef enum_flags<enum_type> type; \
- }
-
-/* Until we can rely on std::underlying type being universally
- available (C++11), roll our own for enums. */
-template<int size, bool sign> class integer_for_size { typedef void type; };
-template<> struct integer_for_size<1, 0> { typedef uint8_t type; };
-template<> struct integer_for_size<2, 0> { typedef uint16_t type; };
-template<> struct integer_for_size<4, 0> { typedef uint32_t type; };
-template<> struct integer_for_size<8, 0> { typedef uint64_t type; };
-template<> struct integer_for_size<1, 1> { typedef int8_t type; };
-template<> struct integer_for_size<2, 1> { typedef int16_t type; };
-template<> struct integer_for_size<4, 1> { typedef int32_t type; };
-template<> struct integer_for_size<8, 1> { typedef int64_t type; };
-
-template<typename T>
-struct enum_underlying_type
-{
- typedef typename
- integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
- type;
-};
-
-template <typename E>
-class enum_flags
-{
-public:
- typedef E enum_type;
- typedef typename enum_underlying_type<enum_type>::type underlying_type;
-
-private:
- /* Private type used to support initializing flag types with zero:
-
- foo_flags f = 0;
-
- but not other integers:
-
- foo_flags f = 1;
-
- The way this works is that we define an implicit constructor that
- takes a pointer to this private type. Since nothing can
- instantiate an object of this type, the only possible pointer to
- pass to the constructor is the NULL pointer, or, zero. */
- struct zero_type;
-
- underlying_type
- underlying_value () const
- {
- return m_enum_value;
- }
-
-public:
- /* Allow default construction. */
- enum_flags ()
- : m_enum_value ((enum_type) 0)
- {}
-
- /* If you get an error saying these two overloads are ambiguous,
- then you tried to mix values of different enum types. */
- enum_flags (enum_type e)
- : m_enum_value (e)
- {}
- enum_flags (struct enum_flags::zero_type *zero)
- : m_enum_value ((enum_type) 0)
- {}
-
- enum_flags &operator&= (enum_type e)
- {
- m_enum_value = (enum_type) (underlying_value () & e);
- return *this;
- }
- enum_flags &operator|= (enum_type e)
- {
- m_enum_value = (enum_type) (underlying_value () | e);
- return *this;
- }
- enum_flags &operator^= (enum_type e)
- {
- m_enum_value = (enum_type) (underlying_value () ^ e);
- return *this;
- }
-
- operator enum_type () const
- {
- return m_enum_value;
- }
-
- enum_flags operator& (enum_type e) const
- {
- return (enum_type) (underlying_value () & e);
- }
- enum_flags operator| (enum_type e) const
- {
- return (enum_type) (underlying_value () | e);
- }
- enum_flags operator^ (enum_type e) const
- {
- return (enum_type) (underlying_value () ^ e);
- }
- enum_flags operator~ () const
- {
- // We only the underlying type to be unsigned when actually using
- // operator~ -- if it were not unsigned, undefined behavior could
- // result. However, asserting this in the class itself would
- // require too many unnecessary changes to otherwise ok enum
- // types.
- gdb_static_assert (std::is_unsigned<underlying_type>::value);
- return (enum_type) ~underlying_value ();
- }
-
-private:
- /* Stored as enum_type because GDB knows to print the bit flags
- neatly if the enum values look like bit flags. */
- enum_type m_enum_value;
-};
-
-/* Global operator overloads. */
-
-template <typename enum_type>
-typename enum_flags_type<enum_type>::type
-operator& (enum_type e1, enum_type e2)
-{
- return enum_flags<enum_type> (e1) & e2;
-}
-
-template <typename enum_type>
-typename enum_flags_type<enum_type>::type
-operator| (enum_type e1, enum_type e2)
-{
- return enum_flags<enum_type> (e1) | e2;
-}
-
-template <typename enum_type>
-typename enum_flags_type<enum_type>::type
-operator^ (enum_type e1, enum_type e2)
-{
- return enum_flags<enum_type> (e1) ^ e2;
-}
-
-template <typename enum_type>
-typename enum_flags_type<enum_type>::type
-operator~ (enum_type e)
-{
- return ~enum_flags<enum_type> (e);
-}
-
-#else /* __cplusplus */
-
-/* In C, the flags type is just a typedef for the enum type. */
-
-#define DEF_ENUM_FLAGS_TYPE(enum_type, flags_type) \
- typedef enum_type flags_type
-
-#endif /* __cplusplus */
-
-#endif /* COMMON_ENUM_FLAGS_H */
projects / thirdparty / binutils-gdb.git / blobdiff