1551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer//===- llvm/Support/type_traits.h - Simplfied type traits -------*- C++ -*-===// 263b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 35c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner// The LLVM Compiler Infrastructure 45c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner// 57ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// This file is distributed under the University of Illinois Open Source 67ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// License. See LICENSE.TXT for details. 763b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 85c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner//===----------------------------------------------------------------------===// 95c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner// 1036b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines// This file provides useful additions to the standard type_traits library. 115c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner// 125c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner//===----------------------------------------------------------------------===// 135c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner 145c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner#ifndef LLVM_SUPPORT_TYPE_TRAITS_H 155c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner#define LLVM_SUPPORT_TYPE_TRAITS_H 165c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner 1736b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines#include <type_traits> 184bbf4ee1491637c247e195e19e3e4a8ee5ad72faChris Lattner#include <utility> 194bbf4ee1491637c247e195e19e3e4a8ee5ad72faChris Lattner 2018883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#ifndef __has_feature 2118883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#define LLVM_DEFINED_HAS_FEATURE 2218883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#define __has_feature(x) 0 2318883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#endif 2418883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer 255c4d53a4d1bce60051fd71af1791791acb2000daChris Lattnernamespace llvm { 265c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner 27dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner/// isPodLike - This is a type trait that is used to determine whether a given 28dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner/// type can be copied around with memcpy instead of running ctors etc. 29dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattnertemplate <typename T> 30dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattnerstruct isPodLike { 3118883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#if __has_feature(is_trivially_copyable) 3218883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer // If the compiler supports the is_trivially_copyable trait use it, as it 3318883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer // matches the definition of isPodLike closely. 3418883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer static const bool value = __is_trivially_copyable(T); 3518883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#else 36dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner // If we don't know anything else, we can (at least) assume that all non-class 37dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner // types are PODs. 3836b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines static const bool value = !std::is_class<T>::value; 3918883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#endif 40dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner}; 41dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner 42dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner// std::pair's are pod-like if their elements are. 43dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattnertemplate<typename T, typename U> 44dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattnerstruct isPodLike<std::pair<T, U> > { 454e58263459d7f9ae862b52adafe585b66411272fBenjamin Kramer static const bool value = isPodLike<T>::value && isPodLike<U>::value; 46dc2e570411bb1b1345a6b9840050aca823835a81Chris Lattner}; 4701812bebcc345b09ce261317b6fdefde8f097642Michael J. Spencer 48ff12877a6f4db734cf0a156dc2ef815a839a79ecChandler Carruth/// \brief Metafunction that determines whether the given type is either an 49ff12877a6f4db734cf0a156dc2ef815a839a79ecChandler Carruth/// integral type or an enumeration type. 50ff12877a6f4db734cf0a156dc2ef815a839a79ecChandler Carruth/// 5136b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// Note that this accepts potentially more integral types than is_integral 5236b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// because it is based on merely being convertible implicitly to an integral 5336b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// type. 54cbfc117674be7ff70b4682c525d6fcb4827a74edChandler Carruthtemplate <typename T> class is_integral_or_enum { 5536b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines typedef typename std::remove_reference<T>::type UnderlyingT; 56cbfc117674be7ff70b4682c525d6fcb4827a74edChandler Carruth 57cbfc117674be7ff70b4682c525d6fcb4827a74edChandler Carruthpublic: 5836b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines static const bool value = 5936b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines !std::is_class<UnderlyingT>::value && // Filter conversion operators. 6036b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines !std::is_pointer<UnderlyingT>::value && 6136b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines !std::is_floating_point<UnderlyingT>::value && 6236b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines std::is_convertible<UnderlyingT, unsigned long long>::value; 63c7a6da6e1469100937851cc3741a36b5850e54daDouglas Gregor}; 64c7a6da6e1469100937851cc3741a36b5850e54daDouglas Gregor 6536b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// \brief If T is a pointer, just return it. If it is not, return T&. 667fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindolatemplate<typename T, typename Enable = void> 677fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindolastruct add_lvalue_reference_if_not_pointer { typedef T &type; }; 687fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola 6936b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hinestemplate <typename T> 7036b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hinesstruct add_lvalue_reference_if_not_pointer< 7136b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines T, typename std::enable_if<std::is_pointer<T>::value>::type> { 727fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola typedef T type; 737fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola}; 747fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola 7536b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// \brief If T is a pointer to X, return a pointer to const X. If it is not, 7636b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines/// return const T. 777fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindolatemplate<typename T, typename Enable = void> 787fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindolastruct add_const_past_pointer { typedef const T type; }; 797fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola 8036b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hinestemplate <typename T> 8136b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hinesstruct add_const_past_pointer< 8236b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines T, typename std::enable_if<std::is_pointer<T>::value>::type> { 8336b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines typedef const typename std::remove_pointer<T>::type *type; 847fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola}; 857fe65d691dcce550d53ec9310913aab67ab6d654Rafael Espindola 865c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner} 875c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner 8818883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#ifdef LLVM_DEFINED_HAS_FEATURE 8918883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#undef __has_feature 9018883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer#endif 9118883037a98240a7831c0d7c01dbe502fc5cfbd9Benjamin Kramer 925c4d53a4d1bce60051fd71af1791791acb2000daChris Lattner#endif 93