projects / thirdparty / gcc.git / blame
| Commit | Line | Data |
|---|---|---|
| 757bf1df DM |
1 | /* "True" vs "False" vs "Unknown". |
| 2 | Copyright (C) 2019-2020 Free Software Foundation, Inc. | |
| 3 | Contributed by David Malcolm <dmalcolm@redhat.com>. | |
| 4 | ||
| 5 | This file is part of GCC. | |
| 6 | ||
| 7 | GCC is free software; you can redistribute it and/or modify it | |
| 8 | under the terms of the GNU General Public License as published by | |
| 9 | the Free Software Foundation; either version 3, or (at your option) | |
| 10 | any later version. | |
| 11 | ||
| 12 | GCC is distributed in the hope that it will be useful, but | |
| 13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 15 | General Public License for more details. | |
| 16 | ||
| 17 | You should have received a copy of the GNU General Public License | |
| 18 | along with GCC; see the file COPYING3. If not see | |
| 19 | <http://www.gnu.org/licenses/>. */ | |
| 20 | ||
| 21 | #ifndef GCC_TRISTATE_H | |
| 22 | #define GCC_TRISTATE_H | |
| 23 | ||
| 24 | /* "True" vs "False" vs "Unknown". */ | |
| 25 | ||
| 26 | class tristate { | |
| 27 | public: | |
| 28 | enum value { | |
| 29 | TS_UNKNOWN, | |
| 30 | TS_TRUE, | |
| 31 | TS_FALSE | |
| 32 | }; | |
| 33 | ||
| 34 | tristate (enum value val) : m_value (val) {} | |
| 35 | tristate (bool val) : m_value (val ? TS_TRUE : TS_FALSE) {} | |
| 36 | static tristate unknown () { return tristate (TS_UNKNOWN); } | |
| 37 | ||
| 38 | const char *as_string () const; | |
| 39 | ||
| 40 | bool is_known () const { return m_value != TS_UNKNOWN; } | |
| 41 | bool is_true () const { return m_value == TS_TRUE; } | |
| 42 | bool is_false () const { return m_value == TS_FALSE; } | |
| 43 | ||
| 44 | tristate not_ () const; | |
| 45 | tristate or_ (tristate other) const; | |
| 46 | tristate and_ (tristate other) const; | |
| 47 | ||
| 48 | bool operator== (const tristate &other) const | |
| 49 | { | |
| 50 | return m_value == other.m_value; | |
| 51 | } | |
| 52 | ||
| 53 | bool operator!= (const tristate &other) const | |
| 54 | { | |
| 55 | return m_value != other.m_value; | |
| 56 | } | |
| 57 | ||
| 58 | private: | |
| 59 | enum value m_value; | |
| 60 | }; | |
| 61 | ||
| 62 | /* Overloaded boolean operators on tristates. */ | |
| 63 | ||
| 64 | inline tristate | |
| 65 | operator ! (tristate t) | |
| 66 | { | |
| 67 | return t.not_ (); | |
| 68 | } | |
| 69 | ||
| 70 | inline tristate | |
| 71 | operator || (tristate a, tristate b) | |
| 72 | { | |
| 73 | return a.or_ (b); | |
| 74 | } | |
| 75 | ||
| 76 | inline tristate | |
| 77 | operator && (tristate a, tristate b) | |
| 78 | { | |
| 79 | return a.and_ (b); | |
| 80 | } | |
| 81 | ||
| 82 | #endif /* GCC_TRISTATE_H */ |