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93375cf94f
Relands patch reverted by 61242c0addb120294211d24a97ed89837418cb36 The original patch mistakenly included unrelated tests. Adds a utility to combine multiple Callables into a single Callable. This is useful to make constructing a visitor for `std::visit`-like functions more natural; functions like this will be added in future patches. Intended to supercede https://reviews.llvm.org/D99560 by perfectly-forwarding the combined Callables. Reviewed By: dblaikie Differential Revision: https://reviews.llvm.org/D100670
2072 lines
74 KiB
C++
2072 lines
74 KiB
C++
//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file contains some templates that are useful if you are working with the
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// STL at all.
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//
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// No library is required when using these functions.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_ADT_STLEXTRAS_H
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#define LLVM_ADT_STLEXTRAS_H
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#include "llvm/ADT/Optional.h"
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#include "llvm/ADT/STLForwardCompat.h"
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#include "llvm/ADT/iterator.h"
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#include "llvm/ADT/iterator_range.h"
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#include "llvm/Config/abi-breaking.h"
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#include "llvm/Support/ErrorHandling.h"
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#include <algorithm>
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#include <cassert>
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#include <cstddef>
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#include <cstdint>
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#include <cstdlib>
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#include <functional>
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#include <initializer_list>
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#include <iterator>
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#include <limits>
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#include <memory>
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#include <tuple>
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#include <type_traits>
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#include <utility>
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#ifdef EXPENSIVE_CHECKS
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#include <random> // for std::mt19937
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#endif
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namespace llvm {
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// Only used by compiler if both template types are the same. Useful when
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// using SFINAE to test for the existence of member functions.
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template <typename T, T> struct SameType;
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namespace detail {
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template <typename RangeT>
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using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
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template <typename RangeT>
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using ValueOfRange = typename std::remove_reference<decltype(
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*std::begin(std::declval<RangeT &>()))>::type;
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} // end namespace detail
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//===----------------------------------------------------------------------===//
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// Extra additions to <type_traits>
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//===----------------------------------------------------------------------===//
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template <typename T> struct make_const_ptr {
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using type =
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typename std::add_pointer<typename std::add_const<T>::type>::type;
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};
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template <typename T> struct make_const_ref {
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using type = typename std::add_lvalue_reference<
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typename std::add_const<T>::type>::type;
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};
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namespace detail {
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template <typename...> using void_t = void;
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template <class, template <class...> class Op, class... Args> struct detector {
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using value_t = std::false_type;
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};
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template <template <class...> class Op, class... Args>
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struct detector<void_t<Op<Args...>>, Op, Args...> {
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using value_t = std::true_type;
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};
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} // end namespace detail
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/// Detects if a given trait holds for some set of arguments 'Args'.
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/// For example, the given trait could be used to detect if a given type
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/// has a copy assignment operator:
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/// template<class T>
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/// using has_copy_assign_t = decltype(std::declval<T&>()
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/// = std::declval<const T&>());
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/// bool fooHasCopyAssign = is_detected<has_copy_assign_t, FooClass>::value;
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template <template <class...> class Op, class... Args>
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using is_detected = typename detail::detector<void, Op, Args...>::value_t;
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namespace detail {
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template <typename Callable, typename... Args>
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using is_invocable =
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decltype(std::declval<Callable &>()(std::declval<Args>()...));
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} // namespace detail
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/// Check if a Callable type can be invoked with the given set of arg types.
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template <typename Callable, typename... Args>
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using is_invocable = is_detected<detail::is_invocable, Callable, Args...>;
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/// This class provides various trait information about a callable object.
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/// * To access the number of arguments: Traits::num_args
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/// * To access the type of an argument: Traits::arg_t<Index>
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/// * To access the type of the result: Traits::result_t
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template <typename T, bool isClass = std::is_class<T>::value>
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struct function_traits : public function_traits<decltype(&T::operator())> {};
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/// Overload for class function types.
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template <typename ClassType, typename ReturnType, typename... Args>
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struct function_traits<ReturnType (ClassType::*)(Args...) const, false> {
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/// The number of arguments to this function.
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enum { num_args = sizeof...(Args) };
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/// The result type of this function.
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using result_t = ReturnType;
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/// The type of an argument to this function.
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template <size_t Index>
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using arg_t = typename std::tuple_element<Index, std::tuple<Args...>>::type;
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};
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/// Overload for class function types.
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template <typename ClassType, typename ReturnType, typename... Args>
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struct function_traits<ReturnType (ClassType::*)(Args...), false>
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: function_traits<ReturnType (ClassType::*)(Args...) const> {};
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/// Overload for non-class function types.
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template <typename ReturnType, typename... Args>
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struct function_traits<ReturnType (*)(Args...), false> {
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/// The number of arguments to this function.
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enum { num_args = sizeof...(Args) };
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/// The result type of this function.
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using result_t = ReturnType;
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/// The type of an argument to this function.
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template <size_t i>
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using arg_t = typename std::tuple_element<i, std::tuple<Args...>>::type;
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};
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/// Overload for non-class function type references.
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template <typename ReturnType, typename... Args>
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struct function_traits<ReturnType (&)(Args...), false>
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: public function_traits<ReturnType (*)(Args...)> {};
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//===----------------------------------------------------------------------===//
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// Extra additions to <functional>
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//===----------------------------------------------------------------------===//
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template <class Ty> struct identity {
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using argument_type = Ty;
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Ty &operator()(Ty &self) const {
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return self;
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}
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const Ty &operator()(const Ty &self) const {
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return self;
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}
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};
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/// An efficient, type-erasing, non-owning reference to a callable. This is
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/// intended for use as the type of a function parameter that is not used
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/// after the function in question returns.
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///
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/// This class does not own the callable, so it is not in general safe to store
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/// a function_ref.
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template<typename Fn> class function_ref;
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template<typename Ret, typename ...Params>
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class function_ref<Ret(Params...)> {
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Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
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intptr_t callable;
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template<typename Callable>
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static Ret callback_fn(intptr_t callable, Params ...params) {
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return (*reinterpret_cast<Callable*>(callable))(
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std::forward<Params>(params)...);
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}
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public:
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function_ref() = default;
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function_ref(std::nullptr_t) {}
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template <typename Callable>
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function_ref(
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Callable &&callable,
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// This is not the copy-constructor.
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std::enable_if_t<!std::is_same<remove_cvref_t<Callable>,
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function_ref>::value> * = nullptr,
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// Functor must be callable and return a suitable type.
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std::enable_if_t<std::is_void<Ret>::value ||
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std::is_convertible<decltype(std::declval<Callable>()(
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std::declval<Params>()...)),
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Ret>::value> * = nullptr)
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: callback(callback_fn<typename std::remove_reference<Callable>::type>),
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callable(reinterpret_cast<intptr_t>(&callable)) {}
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Ret operator()(Params ...params) const {
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return callback(callable, std::forward<Params>(params)...);
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}
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explicit operator bool() const { return callback; }
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};
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//===----------------------------------------------------------------------===//
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// Extra additions to <iterator>
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//===----------------------------------------------------------------------===//
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namespace adl_detail {
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using std::begin;
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template <typename ContainerTy>
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decltype(auto) adl_begin(ContainerTy &&container) {
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return begin(std::forward<ContainerTy>(container));
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}
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using std::end;
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template <typename ContainerTy>
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decltype(auto) adl_end(ContainerTy &&container) {
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return end(std::forward<ContainerTy>(container));
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}
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using std::swap;
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template <typename T>
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void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
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std::declval<T>()))) {
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swap(std::forward<T>(lhs), std::forward<T>(rhs));
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}
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} // end namespace adl_detail
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template <typename ContainerTy>
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decltype(auto) adl_begin(ContainerTy &&container) {
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return adl_detail::adl_begin(std::forward<ContainerTy>(container));
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}
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template <typename ContainerTy>
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decltype(auto) adl_end(ContainerTy &&container) {
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return adl_detail::adl_end(std::forward<ContainerTy>(container));
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}
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template <typename T>
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void adl_swap(T &&lhs, T &&rhs) noexcept(
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noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
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adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
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}
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/// Test whether \p RangeOrContainer is empty. Similar to C++17 std::empty.
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template <typename T>
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constexpr bool empty(const T &RangeOrContainer) {
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return adl_begin(RangeOrContainer) == adl_end(RangeOrContainer);
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}
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/// Returns true if the given container only contains a single element.
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template <typename ContainerTy> bool hasSingleElement(ContainerTy &&C) {
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auto B = std::begin(C), E = std::end(C);
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return B != E && std::next(B) == E;
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}
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/// Return a range covering \p RangeOrContainer with the first N elements
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/// excluded.
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template <typename T> auto drop_begin(T &&RangeOrContainer, size_t N = 1) {
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return make_range(std::next(adl_begin(RangeOrContainer), N),
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adl_end(RangeOrContainer));
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}
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// mapped_iterator - This is a simple iterator adapter that causes a function to
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// be applied whenever operator* is invoked on the iterator.
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template <typename ItTy, typename FuncTy,
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typename FuncReturnTy =
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decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
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class mapped_iterator
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: public iterator_adaptor_base<
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mapped_iterator<ItTy, FuncTy>, ItTy,
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typename std::iterator_traits<ItTy>::iterator_category,
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typename std::remove_reference<FuncReturnTy>::type> {
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public:
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mapped_iterator(ItTy U, FuncTy F)
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: mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
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ItTy getCurrent() { return this->I; }
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FuncReturnTy operator*() const { return F(*this->I); }
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private:
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FuncTy F;
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};
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// map_iterator - Provide a convenient way to create mapped_iterators, just like
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// make_pair is useful for creating pairs...
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template <class ItTy, class FuncTy>
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inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
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return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
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}
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template <class ContainerTy, class FuncTy>
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auto map_range(ContainerTy &&C, FuncTy F) {
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return make_range(map_iterator(C.begin(), F), map_iterator(C.end(), F));
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}
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/// Helper to determine if type T has a member called rbegin().
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template <typename Ty> class has_rbegin_impl {
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using yes = char[1];
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using no = char[2];
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template <typename Inner>
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static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
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template <typename>
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static no& test(...);
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public:
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static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
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};
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/// Metafunction to determine if T& or T has a member called rbegin().
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template <typename Ty>
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struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
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};
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// Returns an iterator_range over the given container which iterates in reverse.
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// Note that the container must have rbegin()/rend() methods for this to work.
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template <typename ContainerTy>
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auto reverse(ContainerTy &&C,
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std::enable_if_t<has_rbegin<ContainerTy>::value> * = nullptr) {
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return make_range(C.rbegin(), C.rend());
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}
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// Returns a std::reverse_iterator wrapped around the given iterator.
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template <typename IteratorTy>
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std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
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return std::reverse_iterator<IteratorTy>(It);
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}
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// Returns an iterator_range over the given container which iterates in reverse.
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// Note that the container must have begin()/end() methods which return
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// bidirectional iterators for this to work.
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template <typename ContainerTy>
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auto reverse(ContainerTy &&C,
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std::enable_if_t<!has_rbegin<ContainerTy>::value> * = nullptr) {
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return make_range(llvm::make_reverse_iterator(std::end(C)),
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llvm::make_reverse_iterator(std::begin(C)));
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}
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/// An iterator adaptor that filters the elements of given inner iterators.
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///
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/// The predicate parameter should be a callable object that accepts the wrapped
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/// iterator's reference type and returns a bool. When incrementing or
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/// decrementing the iterator, it will call the predicate on each element and
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/// skip any where it returns false.
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///
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/// \code
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/// int A[] = { 1, 2, 3, 4 };
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/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
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/// // R contains { 1, 3 }.
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/// \endcode
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///
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/// Note: filter_iterator_base implements support for forward iteration.
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/// filter_iterator_impl exists to provide support for bidirectional iteration,
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/// conditional on whether the wrapped iterator supports it.
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template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
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class filter_iterator_base
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: public iterator_adaptor_base<
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filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
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WrappedIteratorT,
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typename std::common_type<
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IterTag, typename std::iterator_traits<
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WrappedIteratorT>::iterator_category>::type> {
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using BaseT = iterator_adaptor_base<
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filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
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WrappedIteratorT,
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typename std::common_type<
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IterTag, typename std::iterator_traits<
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WrappedIteratorT>::iterator_category>::type>;
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protected:
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WrappedIteratorT End;
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PredicateT Pred;
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void findNextValid() {
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while (this->I != End && !Pred(*this->I))
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BaseT::operator++();
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}
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// Construct the iterator. The begin iterator needs to know where the end
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// is, so that it can properly stop when it gets there. The end iterator only
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// needs the predicate to support bidirectional iteration.
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filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
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PredicateT Pred)
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: BaseT(Begin), End(End), Pred(Pred) {
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findNextValid();
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}
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public:
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using BaseT::operator++;
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filter_iterator_base &operator++() {
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BaseT::operator++();
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findNextValid();
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return *this;
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}
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};
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/// Specialization of filter_iterator_base for forward iteration only.
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template <typename WrappedIteratorT, typename PredicateT,
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typename IterTag = std::forward_iterator_tag>
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class filter_iterator_impl
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: public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
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using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
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public:
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filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
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PredicateT Pred)
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: BaseT(Begin, End, Pred) {}
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};
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/// Specialization of filter_iterator_base for bidirectional iteration.
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template <typename WrappedIteratorT, typename PredicateT>
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class filter_iterator_impl<WrappedIteratorT, PredicateT,
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std::bidirectional_iterator_tag>
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: public filter_iterator_base<WrappedIteratorT, PredicateT,
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std::bidirectional_iterator_tag> {
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using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
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std::bidirectional_iterator_tag>;
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void findPrevValid() {
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while (!this->Pred(*this->I))
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BaseT::operator--();
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}
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public:
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using BaseT::operator--;
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filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
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PredicateT Pred)
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: BaseT(Begin, End, Pred) {}
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filter_iterator_impl &operator--() {
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BaseT::operator--();
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findPrevValid();
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return *this;
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}
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};
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namespace detail {
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template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
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using type = std::forward_iterator_tag;
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};
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template <> struct fwd_or_bidi_tag_impl<true> {
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using type = std::bidirectional_iterator_tag;
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};
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/// Helper which sets its type member to forward_iterator_tag if the category
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/// of \p IterT does not derive from bidirectional_iterator_tag, and to
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/// bidirectional_iterator_tag otherwise.
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template <typename IterT> struct fwd_or_bidi_tag {
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using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
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std::bidirectional_iterator_tag,
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typename std::iterator_traits<IterT>::iterator_category>::value>::type;
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};
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} // namespace detail
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/// Defines filter_iterator to a suitable specialization of
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/// filter_iterator_impl, based on the underlying iterator's category.
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template <typename WrappedIteratorT, typename PredicateT>
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using filter_iterator = filter_iterator_impl<
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WrappedIteratorT, PredicateT,
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typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
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/// Convenience function that takes a range of elements and a predicate,
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/// and return a new filter_iterator range.
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///
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/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
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/// lifetime of that temporary is not kept by the returned range object, and the
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/// temporary is going to be dropped on the floor after the make_iterator_range
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/// full expression that contains this function call.
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template <typename RangeT, typename PredicateT>
|
|
iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
|
|
make_filter_range(RangeT &&Range, PredicateT Pred) {
|
|
using FilterIteratorT =
|
|
filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
|
|
return make_range(
|
|
FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
|
|
std::end(std::forward<RangeT>(Range)), Pred),
|
|
FilterIteratorT(std::end(std::forward<RangeT>(Range)),
|
|
std::end(std::forward<RangeT>(Range)), Pred));
|
|
}
|
|
|
|
/// A pseudo-iterator adaptor that is designed to implement "early increment"
|
|
/// style loops.
|
|
///
|
|
/// This is *not a normal iterator* and should almost never be used directly. It
|
|
/// is intended primarily to be used with range based for loops and some range
|
|
/// algorithms.
|
|
///
|
|
/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
|
|
/// somewhere between them. The constraints of these iterators are:
|
|
///
|
|
/// - On construction or after being incremented, it is comparable and
|
|
/// dereferencable. It is *not* incrementable.
|
|
/// - After being dereferenced, it is neither comparable nor dereferencable, it
|
|
/// is only incrementable.
|
|
///
|
|
/// This means you can only dereference the iterator once, and you can only
|
|
/// increment it once between dereferences.
|
|
template <typename WrappedIteratorT>
|
|
class early_inc_iterator_impl
|
|
: public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
|
|
WrappedIteratorT, std::input_iterator_tag> {
|
|
using BaseT =
|
|
iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
|
|
WrappedIteratorT, std::input_iterator_tag>;
|
|
|
|
using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
|
|
|
|
protected:
|
|
#if LLVM_ENABLE_ABI_BREAKING_CHECKS
|
|
bool IsEarlyIncremented = false;
|
|
#endif
|
|
|
|
public:
|
|
early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
|
|
|
|
using BaseT::operator*;
|
|
decltype(*std::declval<WrappedIteratorT>()) operator*() {
|
|
#if LLVM_ENABLE_ABI_BREAKING_CHECKS
|
|
assert(!IsEarlyIncremented && "Cannot dereference twice!");
|
|
IsEarlyIncremented = true;
|
|
#endif
|
|
return *(this->I)++;
|
|
}
|
|
|
|
using BaseT::operator++;
|
|
early_inc_iterator_impl &operator++() {
|
|
#if LLVM_ENABLE_ABI_BREAKING_CHECKS
|
|
assert(IsEarlyIncremented && "Cannot increment before dereferencing!");
|
|
IsEarlyIncremented = false;
|
|
#endif
|
|
return *this;
|
|
}
|
|
|
|
friend bool operator==(const early_inc_iterator_impl &LHS,
|
|
const early_inc_iterator_impl &RHS) {
|
|
#if LLVM_ENABLE_ABI_BREAKING_CHECKS
|
|
assert(!LHS.IsEarlyIncremented && "Cannot compare after dereferencing!");
|
|
#endif
|
|
return (const BaseT &)LHS == (const BaseT &)RHS;
|
|
}
|
|
};
|
|
|
|
/// Make a range that does early increment to allow mutation of the underlying
|
|
/// range without disrupting iteration.
|
|
///
|
|
/// The underlying iterator will be incremented immediately after it is
|
|
/// dereferenced, allowing deletion of the current node or insertion of nodes to
|
|
/// not disrupt iteration provided they do not invalidate the *next* iterator --
|
|
/// the current iterator can be invalidated.
|
|
///
|
|
/// This requires a very exact pattern of use that is only really suitable to
|
|
/// range based for loops and other range algorithms that explicitly guarantee
|
|
/// to dereference exactly once each element, and to increment exactly once each
|
|
/// element.
|
|
template <typename RangeT>
|
|
iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
|
|
make_early_inc_range(RangeT &&Range) {
|
|
using EarlyIncIteratorT =
|
|
early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
|
|
return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
|
|
EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
|
|
}
|
|
|
|
// forward declarations required by zip_shortest/zip_first/zip_longest
|
|
template <typename R, typename UnaryPredicate>
|
|
bool all_of(R &&range, UnaryPredicate P);
|
|
template <typename R, typename UnaryPredicate>
|
|
bool any_of(R &&range, UnaryPredicate P);
|
|
|
|
namespace detail {
|
|
|
|
using std::declval;
|
|
|
|
// We have to alias this since inlining the actual type at the usage site
|
|
// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
|
|
template<typename... Iters> struct ZipTupleType {
|
|
using type = std::tuple<decltype(*declval<Iters>())...>;
|
|
};
|
|
|
|
template <typename ZipType, typename... Iters>
|
|
using zip_traits = iterator_facade_base<
|
|
ZipType, typename std::common_type<std::bidirectional_iterator_tag,
|
|
typename std::iterator_traits<
|
|
Iters>::iterator_category...>::type,
|
|
// ^ TODO: Implement random access methods.
|
|
typename ZipTupleType<Iters...>::type,
|
|
typename std::iterator_traits<typename std::tuple_element<
|
|
0, std::tuple<Iters...>>::type>::difference_type,
|
|
// ^ FIXME: This follows boost::make_zip_iterator's assumption that all
|
|
// inner iterators have the same difference_type. It would fail if, for
|
|
// instance, the second field's difference_type were non-numeric while the
|
|
// first is.
|
|
typename ZipTupleType<Iters...>::type *,
|
|
typename ZipTupleType<Iters...>::type>;
|
|
|
|
template <typename ZipType, typename... Iters>
|
|
struct zip_common : public zip_traits<ZipType, Iters...> {
|
|
using Base = zip_traits<ZipType, Iters...>;
|
|
using value_type = typename Base::value_type;
|
|
|
|
std::tuple<Iters...> iterators;
|
|
|
|
protected:
|
|
template <size_t... Ns> value_type deref(std::index_sequence<Ns...>) const {
|
|
return value_type(*std::get<Ns>(iterators)...);
|
|
}
|
|
|
|
template <size_t... Ns>
|
|
decltype(iterators) tup_inc(std::index_sequence<Ns...>) const {
|
|
return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
|
|
}
|
|
|
|
template <size_t... Ns>
|
|
decltype(iterators) tup_dec(std::index_sequence<Ns...>) const {
|
|
return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
|
|
}
|
|
|
|
public:
|
|
zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
|
|
|
|
value_type operator*() { return deref(std::index_sequence_for<Iters...>{}); }
|
|
|
|
const value_type operator*() const {
|
|
return deref(std::index_sequence_for<Iters...>{});
|
|
}
|
|
|
|
ZipType &operator++() {
|
|
iterators = tup_inc(std::index_sequence_for<Iters...>{});
|
|
return *reinterpret_cast<ZipType *>(this);
|
|
}
|
|
|
|
ZipType &operator--() {
|
|
static_assert(Base::IsBidirectional,
|
|
"All inner iterators must be at least bidirectional.");
|
|
iterators = tup_dec(std::index_sequence_for<Iters...>{});
|
|
return *reinterpret_cast<ZipType *>(this);
|
|
}
|
|
};
|
|
|
|
template <typename... Iters>
|
|
struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
|
|
using Base = zip_common<zip_first<Iters...>, Iters...>;
|
|
|
|
bool operator==(const zip_first<Iters...> &other) const {
|
|
return std::get<0>(this->iterators) == std::get<0>(other.iterators);
|
|
}
|
|
|
|
zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
|
|
};
|
|
|
|
template <typename... Iters>
|
|
class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
|
|
template <size_t... Ns>
|
|
bool test(const zip_shortest<Iters...> &other,
|
|
std::index_sequence<Ns...>) const {
|
|
return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
|
|
std::get<Ns>(other.iterators)...},
|
|
identity<bool>{});
|
|
}
|
|
|
|
public:
|
|
using Base = zip_common<zip_shortest<Iters...>, Iters...>;
|
|
|
|
zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
|
|
|
|
bool operator==(const zip_shortest<Iters...> &other) const {
|
|
return !test(other, std::index_sequence_for<Iters...>{});
|
|
}
|
|
};
|
|
|
|
template <template <typename...> class ItType, typename... Args> class zippy {
|
|
public:
|
|
using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
|
|
using iterator_category = typename iterator::iterator_category;
|
|
using value_type = typename iterator::value_type;
|
|
using difference_type = typename iterator::difference_type;
|
|
using pointer = typename iterator::pointer;
|
|
using reference = typename iterator::reference;
|
|
|
|
private:
|
|
std::tuple<Args...> ts;
|
|
|
|
template <size_t... Ns>
|
|
iterator begin_impl(std::index_sequence<Ns...>) const {
|
|
return iterator(std::begin(std::get<Ns>(ts))...);
|
|
}
|
|
template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) const {
|
|
return iterator(std::end(std::get<Ns>(ts))...);
|
|
}
|
|
|
|
public:
|
|
zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
|
|
|
|
iterator begin() const {
|
|
return begin_impl(std::index_sequence_for<Args...>{});
|
|
}
|
|
iterator end() const { return end_impl(std::index_sequence_for<Args...>{}); }
|
|
};
|
|
|
|
} // end namespace detail
|
|
|
|
/// zip iterator for two or more iteratable types.
|
|
template <typename T, typename U, typename... Args>
|
|
detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
|
|
Args &&... args) {
|
|
return detail::zippy<detail::zip_shortest, T, U, Args...>(
|
|
std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
|
|
}
|
|
|
|
/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
|
|
/// be the shortest.
|
|
template <typename T, typename U, typename... Args>
|
|
detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
|
|
Args &&... args) {
|
|
return detail::zippy<detail::zip_first, T, U, Args...>(
|
|
std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
|
|
}
|
|
|
|
namespace detail {
|
|
template <typename Iter>
|
|
Iter next_or_end(const Iter &I, const Iter &End) {
|
|
if (I == End)
|
|
return End;
|
|
return std::next(I);
|
|
}
|
|
|
|
template <typename Iter>
|
|
auto deref_or_none(const Iter &I, const Iter &End) -> llvm::Optional<
|
|
std::remove_const_t<std::remove_reference_t<decltype(*I)>>> {
|
|
if (I == End)
|
|
return None;
|
|
return *I;
|
|
}
|
|
|
|
template <typename Iter> struct ZipLongestItemType {
|
|
using type =
|
|
llvm::Optional<typename std::remove_const<typename std::remove_reference<
|
|
decltype(*std::declval<Iter>())>::type>::type>;
|
|
};
|
|
|
|
template <typename... Iters> struct ZipLongestTupleType {
|
|
using type = std::tuple<typename ZipLongestItemType<Iters>::type...>;
|
|
};
|
|
|
|
template <typename... Iters>
|
|
class zip_longest_iterator
|
|
: public iterator_facade_base<
|
|
zip_longest_iterator<Iters...>,
|
|
typename std::common_type<
|
|
std::forward_iterator_tag,
|
|
typename std::iterator_traits<Iters>::iterator_category...>::type,
|
|
typename ZipLongestTupleType<Iters...>::type,
|
|
typename std::iterator_traits<typename std::tuple_element<
|
|
0, std::tuple<Iters...>>::type>::difference_type,
|
|
typename ZipLongestTupleType<Iters...>::type *,
|
|
typename ZipLongestTupleType<Iters...>::type> {
|
|
public:
|
|
using value_type = typename ZipLongestTupleType<Iters...>::type;
|
|
|
|
private:
|
|
std::tuple<Iters...> iterators;
|
|
std::tuple<Iters...> end_iterators;
|
|
|
|
template <size_t... Ns>
|
|
bool test(const zip_longest_iterator<Iters...> &other,
|
|
std::index_sequence<Ns...>) const {
|
|
return llvm::any_of(
|
|
std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
|
|
std::get<Ns>(other.iterators)...},
|
|
identity<bool>{});
|
|
}
|
|
|
|
template <size_t... Ns> value_type deref(std::index_sequence<Ns...>) const {
|
|
return value_type(
|
|
deref_or_none(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
|
|
}
|
|
|
|
template <size_t... Ns>
|
|
decltype(iterators) tup_inc(std::index_sequence<Ns...>) const {
|
|
return std::tuple<Iters...>(
|
|
next_or_end(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
|
|
}
|
|
|
|
public:
|
|
zip_longest_iterator(std::pair<Iters &&, Iters &&>... ts)
|
|
: iterators(std::forward<Iters>(ts.first)...),
|
|
end_iterators(std::forward<Iters>(ts.second)...) {}
|
|
|
|
value_type operator*() { return deref(std::index_sequence_for<Iters...>{}); }
|
|
|
|
value_type operator*() const {
|
|
return deref(std::index_sequence_for<Iters...>{});
|
|
}
|
|
|
|
zip_longest_iterator<Iters...> &operator++() {
|
|
iterators = tup_inc(std::index_sequence_for<Iters...>{});
|
|
return *this;
|
|
}
|
|
|
|
bool operator==(const zip_longest_iterator<Iters...> &other) const {
|
|
return !test(other, std::index_sequence_for<Iters...>{});
|
|
}
|
|
};
|
|
|
|
template <typename... Args> class zip_longest_range {
|
|
public:
|
|
using iterator =
|
|
zip_longest_iterator<decltype(adl_begin(std::declval<Args>()))...>;
|
|
using iterator_category = typename iterator::iterator_category;
|
|
using value_type = typename iterator::value_type;
|
|
using difference_type = typename iterator::difference_type;
|
|
using pointer = typename iterator::pointer;
|
|
using reference = typename iterator::reference;
|
|
|
|
private:
|
|
std::tuple<Args...> ts;
|
|
|
|
template <size_t... Ns>
|
|
iterator begin_impl(std::index_sequence<Ns...>) const {
|
|
return iterator(std::make_pair(adl_begin(std::get<Ns>(ts)),
|
|
adl_end(std::get<Ns>(ts)))...);
|
|
}
|
|
|
|
template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) const {
|
|
return iterator(std::make_pair(adl_end(std::get<Ns>(ts)),
|
|
adl_end(std::get<Ns>(ts)))...);
|
|
}
|
|
|
|
public:
|
|
zip_longest_range(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
|
|
|
|
iterator begin() const {
|
|
return begin_impl(std::index_sequence_for<Args...>{});
|
|
}
|
|
iterator end() const { return end_impl(std::index_sequence_for<Args...>{}); }
|
|
};
|
|
} // namespace detail
|
|
|
|
/// Iterate over two or more iterators at the same time. Iteration continues
|
|
/// until all iterators reach the end. The llvm::Optional only contains a value
|
|
/// if the iterator has not reached the end.
|
|
template <typename T, typename U, typename... Args>
|
|
detail::zip_longest_range<T, U, Args...> zip_longest(T &&t, U &&u,
|
|
Args &&... args) {
|
|
return detail::zip_longest_range<T, U, Args...>(
|
|
std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
|
|
}
|
|
|
|
/// Iterator wrapper that concatenates sequences together.
|
|
///
|
|
/// This can concatenate different iterators, even with different types, into
|
|
/// a single iterator provided the value types of all the concatenated
|
|
/// iterators expose `reference` and `pointer` types that can be converted to
|
|
/// `ValueT &` and `ValueT *` respectively. It doesn't support more
|
|
/// interesting/customized pointer or reference types.
|
|
///
|
|
/// Currently this only supports forward or higher iterator categories as
|
|
/// inputs and always exposes a forward iterator interface.
|
|
template <typename ValueT, typename... IterTs>
|
|
class concat_iterator
|
|
: public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
|
|
std::forward_iterator_tag, ValueT> {
|
|
using BaseT = typename concat_iterator::iterator_facade_base;
|
|
|
|
/// We store both the current and end iterators for each concatenated
|
|
/// sequence in a tuple of pairs.
|
|
///
|
|
/// Note that something like iterator_range seems nice at first here, but the
|
|
/// range properties are of little benefit and end up getting in the way
|
|
/// because we need to do mutation on the current iterators.
|
|
std::tuple<IterTs...> Begins;
|
|
std::tuple<IterTs...> Ends;
|
|
|
|
/// Attempts to increment a specific iterator.
|
|
///
|
|
/// Returns true if it was able to increment the iterator. Returns false if
|
|
/// the iterator is already at the end iterator.
|
|
template <size_t Index> bool incrementHelper() {
|
|
auto &Begin = std::get<Index>(Begins);
|
|
auto &End = std::get<Index>(Ends);
|
|
if (Begin == End)
|
|
return false;
|
|
|
|
++Begin;
|
|
return true;
|
|
}
|
|
|
|
/// Increments the first non-end iterator.
|
|
///
|
|
/// It is an error to call this with all iterators at the end.
|
|
template <size_t... Ns> void increment(std::index_sequence<Ns...>) {
|
|
// Build a sequence of functions to increment each iterator if possible.
|
|
bool (concat_iterator::*IncrementHelperFns[])() = {
|
|
&concat_iterator::incrementHelper<Ns>...};
|
|
|
|
// Loop over them, and stop as soon as we succeed at incrementing one.
|
|
for (auto &IncrementHelperFn : IncrementHelperFns)
|
|
if ((this->*IncrementHelperFn)())
|
|
return;
|
|
|
|
llvm_unreachable("Attempted to increment an end concat iterator!");
|
|
}
|
|
|
|
/// Returns null if the specified iterator is at the end. Otherwise,
|
|
/// dereferences the iterator and returns the address of the resulting
|
|
/// reference.
|
|
template <size_t Index> ValueT *getHelper() const {
|
|
auto &Begin = std::get<Index>(Begins);
|
|
auto &End = std::get<Index>(Ends);
|
|
if (Begin == End)
|
|
return nullptr;
|
|
|
|
return &*Begin;
|
|
}
|
|
|
|
/// Finds the first non-end iterator, dereferences, and returns the resulting
|
|
/// reference.
|
|
///
|
|
/// It is an error to call this with all iterators at the end.
|
|
template <size_t... Ns> ValueT &get(std::index_sequence<Ns...>) const {
|
|
// Build a sequence of functions to get from iterator if possible.
|
|
ValueT *(concat_iterator::*GetHelperFns[])() const = {
|
|
&concat_iterator::getHelper<Ns>...};
|
|
|
|
// Loop over them, and return the first result we find.
|
|
for (auto &GetHelperFn : GetHelperFns)
|
|
if (ValueT *P = (this->*GetHelperFn)())
|
|
return *P;
|
|
|
|
llvm_unreachable("Attempted to get a pointer from an end concat iterator!");
|
|
}
|
|
|
|
public:
|
|
/// Constructs an iterator from a sequence of ranges.
|
|
///
|
|
/// We need the full range to know how to switch between each of the
|
|
/// iterators.
|
|
template <typename... RangeTs>
|
|
explicit concat_iterator(RangeTs &&... Ranges)
|
|
: Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
|
|
|
|
using BaseT::operator++;
|
|
|
|
concat_iterator &operator++() {
|
|
increment(std::index_sequence_for<IterTs...>());
|
|
return *this;
|
|
}
|
|
|
|
ValueT &operator*() const {
|
|
return get(std::index_sequence_for<IterTs...>());
|
|
}
|
|
|
|
bool operator==(const concat_iterator &RHS) const {
|
|
return Begins == RHS.Begins && Ends == RHS.Ends;
|
|
}
|
|
};
|
|
|
|
namespace detail {
|
|
|
|
/// Helper to store a sequence of ranges being concatenated and access them.
|
|
///
|
|
/// This is designed to facilitate providing actual storage when temporaries
|
|
/// are passed into the constructor such that we can use it as part of range
|
|
/// based for loops.
|
|
template <typename ValueT, typename... RangeTs> class concat_range {
|
|
public:
|
|
using iterator =
|
|
concat_iterator<ValueT,
|
|
decltype(std::begin(std::declval<RangeTs &>()))...>;
|
|
|
|
private:
|
|
std::tuple<RangeTs...> Ranges;
|
|
|
|
template <size_t... Ns> iterator begin_impl(std::index_sequence<Ns...>) {
|
|
return iterator(std::get<Ns>(Ranges)...);
|
|
}
|
|
template <size_t... Ns> iterator end_impl(std::index_sequence<Ns...>) {
|
|
return iterator(make_range(std::end(std::get<Ns>(Ranges)),
|
|
std::end(std::get<Ns>(Ranges)))...);
|
|
}
|
|
|
|
public:
|
|
concat_range(RangeTs &&... Ranges)
|
|
: Ranges(std::forward<RangeTs>(Ranges)...) {}
|
|
|
|
iterator begin() { return begin_impl(std::index_sequence_for<RangeTs...>{}); }
|
|
iterator end() { return end_impl(std::index_sequence_for<RangeTs...>{}); }
|
|
};
|
|
|
|
} // end namespace detail
|
|
|
|
/// Concatenated range across two or more ranges.
|
|
///
|
|
/// The desired value type must be explicitly specified.
|
|
template <typename ValueT, typename... RangeTs>
|
|
detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
|
|
static_assert(sizeof...(RangeTs) > 1,
|
|
"Need more than one range to concatenate!");
|
|
return detail::concat_range<ValueT, RangeTs...>(
|
|
std::forward<RangeTs>(Ranges)...);
|
|
}
|
|
|
|
/// A utility class used to implement an iterator that contains some base object
|
|
/// and an index. The iterator moves the index but keeps the base constant.
|
|
template <typename DerivedT, typename BaseT, typename T,
|
|
typename PointerT = T *, typename ReferenceT = T &>
|
|
class indexed_accessor_iterator
|
|
: public llvm::iterator_facade_base<DerivedT,
|
|
std::random_access_iterator_tag, T,
|
|
std::ptrdiff_t, PointerT, ReferenceT> {
|
|
public:
|
|
ptrdiff_t operator-(const indexed_accessor_iterator &rhs) const {
|
|
assert(base == rhs.base && "incompatible iterators");
|
|
return index - rhs.index;
|
|
}
|
|
bool operator==(const indexed_accessor_iterator &rhs) const {
|
|
return base == rhs.base && index == rhs.index;
|
|
}
|
|
bool operator<(const indexed_accessor_iterator &rhs) const {
|
|
assert(base == rhs.base && "incompatible iterators");
|
|
return index < rhs.index;
|
|
}
|
|
|
|
DerivedT &operator+=(ptrdiff_t offset) {
|
|
this->index += offset;
|
|
return static_cast<DerivedT &>(*this);
|
|
}
|
|
DerivedT &operator-=(ptrdiff_t offset) {
|
|
this->index -= offset;
|
|
return static_cast<DerivedT &>(*this);
|
|
}
|
|
|
|
/// Returns the current index of the iterator.
|
|
ptrdiff_t getIndex() const { return index; }
|
|
|
|
/// Returns the current base of the iterator.
|
|
const BaseT &getBase() const { return base; }
|
|
|
|
protected:
|
|
indexed_accessor_iterator(BaseT base, ptrdiff_t index)
|
|
: base(base), index(index) {}
|
|
BaseT base;
|
|
ptrdiff_t index;
|
|
};
|
|
|
|
namespace detail {
|
|
/// The class represents the base of a range of indexed_accessor_iterators. It
|
|
/// provides support for many different range functionalities, e.g.
|
|
/// drop_front/slice/etc.. Derived range classes must implement the following
|
|
/// static methods:
|
|
/// * ReferenceT dereference_iterator(const BaseT &base, ptrdiff_t index)
|
|
/// - Dereference an iterator pointing to the base object at the given
|
|
/// index.
|
|
/// * BaseT offset_base(const BaseT &base, ptrdiff_t index)
|
|
/// - Return a new base that is offset from the provide base by 'index'
|
|
/// elements.
|
|
template <typename DerivedT, typename BaseT, typename T,
|
|
typename PointerT = T *, typename ReferenceT = T &>
|
|
class indexed_accessor_range_base {
|
|
public:
|
|
using RangeBaseT =
|
|
indexed_accessor_range_base<DerivedT, BaseT, T, PointerT, ReferenceT>;
|
|
|
|
/// An iterator element of this range.
|
|
class iterator : public indexed_accessor_iterator<iterator, BaseT, T,
|
|
PointerT, ReferenceT> {
|
|
public:
|
|
// Index into this iterator, invoking a static method on the derived type.
|
|
ReferenceT operator*() const {
|
|
return DerivedT::dereference_iterator(this->getBase(), this->getIndex());
|
|
}
|
|
|
|
private:
|
|
iterator(BaseT owner, ptrdiff_t curIndex)
|
|
: indexed_accessor_iterator<iterator, BaseT, T, PointerT, ReferenceT>(
|
|
owner, curIndex) {}
|
|
|
|
/// Allow access to the constructor.
|
|
friend indexed_accessor_range_base<DerivedT, BaseT, T, PointerT,
|
|
ReferenceT>;
|
|
};
|
|
|
|
indexed_accessor_range_base(iterator begin, iterator end)
|
|
: base(offset_base(begin.getBase(), begin.getIndex())),
|
|
count(end.getIndex() - begin.getIndex()) {}
|
|
indexed_accessor_range_base(const iterator_range<iterator> &range)
|
|
: indexed_accessor_range_base(range.begin(), range.end()) {}
|
|
indexed_accessor_range_base(BaseT base, ptrdiff_t count)
|
|
: base(base), count(count) {}
|
|
|
|
iterator begin() const { return iterator(base, 0); }
|
|
iterator end() const { return iterator(base, count); }
|
|
ReferenceT operator[](size_t Index) const {
|
|
assert(Index < size() && "invalid index for value range");
|
|
return DerivedT::dereference_iterator(base, static_cast<ptrdiff_t>(Index));
|
|
}
|
|
ReferenceT front() const {
|
|
assert(!empty() && "expected non-empty range");
|
|
return (*this)[0];
|
|
}
|
|
ReferenceT back() const {
|
|
assert(!empty() && "expected non-empty range");
|
|
return (*this)[size() - 1];
|
|
}
|
|
|
|
/// Compare this range with another.
|
|
template <typename OtherT> bool operator==(const OtherT &other) const {
|
|
return size() ==
|
|
static_cast<size_t>(std::distance(other.begin(), other.end())) &&
|
|
std::equal(begin(), end(), other.begin());
|
|
}
|
|
template <typename OtherT> bool operator!=(const OtherT &other) const {
|
|
return !(*this == other);
|
|
}
|
|
|
|
/// Return the size of this range.
|
|
size_t size() const { return count; }
|
|
|
|
/// Return if the range is empty.
|
|
bool empty() const { return size() == 0; }
|
|
|
|
/// Drop the first N elements, and keep M elements.
|
|
DerivedT slice(size_t n, size_t m) const {
|
|
assert(n + m <= size() && "invalid size specifiers");
|
|
return DerivedT(offset_base(base, n), m);
|
|
}
|
|
|
|
/// Drop the first n elements.
|
|
DerivedT drop_front(size_t n = 1) const {
|
|
assert(size() >= n && "Dropping more elements than exist");
|
|
return slice(n, size() - n);
|
|
}
|
|
/// Drop the last n elements.
|
|
DerivedT drop_back(size_t n = 1) const {
|
|
assert(size() >= n && "Dropping more elements than exist");
|
|
return DerivedT(base, size() - n);
|
|
}
|
|
|
|
/// Take the first n elements.
|
|
DerivedT take_front(size_t n = 1) const {
|
|
return n < size() ? drop_back(size() - n)
|
|
: static_cast<const DerivedT &>(*this);
|
|
}
|
|
|
|
/// Take the last n elements.
|
|
DerivedT take_back(size_t n = 1) const {
|
|
return n < size() ? drop_front(size() - n)
|
|
: static_cast<const DerivedT &>(*this);
|
|
}
|
|
|
|
/// Allow conversion to any type accepting an iterator_range.
|
|
template <typename RangeT, typename = std::enable_if_t<std::is_constructible<
|
|
RangeT, iterator_range<iterator>>::value>>
|
|
operator RangeT() const {
|
|
return RangeT(iterator_range<iterator>(*this));
|
|
}
|
|
|
|
/// Returns the base of this range.
|
|
const BaseT &getBase() const { return base; }
|
|
|
|
private:
|
|
/// Offset the given base by the given amount.
|
|
static BaseT offset_base(const BaseT &base, size_t n) {
|
|
return n == 0 ? base : DerivedT::offset_base(base, n);
|
|
}
|
|
|
|
protected:
|
|
indexed_accessor_range_base(const indexed_accessor_range_base &) = default;
|
|
indexed_accessor_range_base(indexed_accessor_range_base &&) = default;
|
|
indexed_accessor_range_base &
|
|
operator=(const indexed_accessor_range_base &) = default;
|
|
|
|
/// The base that owns the provided range of values.
|
|
BaseT base;
|
|
/// The size from the owning range.
|
|
ptrdiff_t count;
|
|
};
|
|
} // end namespace detail
|
|
|
|
/// This class provides an implementation of a range of
|
|
/// indexed_accessor_iterators where the base is not indexable. Ranges with
|
|
/// bases that are offsetable should derive from indexed_accessor_range_base
|
|
/// instead. Derived range classes are expected to implement the following
|
|
/// static method:
|
|
/// * ReferenceT dereference(const BaseT &base, ptrdiff_t index)
|
|
/// - Dereference an iterator pointing to a parent base at the given index.
|
|
template <typename DerivedT, typename BaseT, typename T,
|
|
typename PointerT = T *, typename ReferenceT = T &>
|
|
class indexed_accessor_range
|
|
: public detail::indexed_accessor_range_base<
|
|
DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT, ReferenceT> {
|
|
public:
|
|
indexed_accessor_range(BaseT base, ptrdiff_t startIndex, ptrdiff_t count)
|
|
: detail::indexed_accessor_range_base<
|
|
DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT, ReferenceT>(
|
|
std::make_pair(base, startIndex), count) {}
|
|
using detail::indexed_accessor_range_base<
|
|
DerivedT, std::pair<BaseT, ptrdiff_t>, T, PointerT,
|
|
ReferenceT>::indexed_accessor_range_base;
|
|
|
|
/// Returns the current base of the range.
|
|
const BaseT &getBase() const { return this->base.first; }
|
|
|
|
/// Returns the current start index of the range.
|
|
ptrdiff_t getStartIndex() const { return this->base.second; }
|
|
|
|
/// See `detail::indexed_accessor_range_base` for details.
|
|
static std::pair<BaseT, ptrdiff_t>
|
|
offset_base(const std::pair<BaseT, ptrdiff_t> &base, ptrdiff_t index) {
|
|
// We encode the internal base as a pair of the derived base and a start
|
|
// index into the derived base.
|
|
return std::make_pair(base.first, base.second + index);
|
|
}
|
|
/// See `detail::indexed_accessor_range_base` for details.
|
|
static ReferenceT
|
|
dereference_iterator(const std::pair<BaseT, ptrdiff_t> &base,
|
|
ptrdiff_t index) {
|
|
return DerivedT::dereference(base.first, base.second + index);
|
|
}
|
|
};
|
|
|
|
/// Given a container of pairs, return a range over the first elements.
|
|
template <typename ContainerTy> auto make_first_range(ContainerTy &&c) {
|
|
return llvm::map_range(
|
|
std::forward<ContainerTy>(c),
|
|
[](decltype((*std::begin(c))) elt) -> decltype((elt.first)) {
|
|
return elt.first;
|
|
});
|
|
}
|
|
|
|
/// Given a container of pairs, return a range over the second elements.
|
|
template <typename ContainerTy> auto make_second_range(ContainerTy &&c) {
|
|
return llvm::map_range(
|
|
std::forward<ContainerTy>(c),
|
|
[](decltype((*std::begin(c))) elt) -> decltype((elt.second)) {
|
|
return elt.second;
|
|
});
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Extra additions to <utility>
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// Function object to check whether the first component of a std::pair
|
|
/// compares less than the first component of another std::pair.
|
|
struct less_first {
|
|
template <typename T> bool operator()(const T &lhs, const T &rhs) const {
|
|
return lhs.first < rhs.first;
|
|
}
|
|
};
|
|
|
|
/// Function object to check whether the second component of a std::pair
|
|
/// compares less than the second component of another std::pair.
|
|
struct less_second {
|
|
template <typename T> bool operator()(const T &lhs, const T &rhs) const {
|
|
return lhs.second < rhs.second;
|
|
}
|
|
};
|
|
|
|
/// \brief Function object to apply a binary function to the first component of
|
|
/// a std::pair.
|
|
template<typename FuncTy>
|
|
struct on_first {
|
|
FuncTy func;
|
|
|
|
template <typename T>
|
|
decltype(auto) operator()(const T &lhs, const T &rhs) const {
|
|
return func(lhs.first, rhs.first);
|
|
}
|
|
};
|
|
|
|
/// Utility type to build an inheritance chain that makes it easy to rank
|
|
/// overload candidates.
|
|
template <int N> struct rank : rank<N - 1> {};
|
|
template <> struct rank<0> {};
|
|
|
|
/// traits class for checking whether type T is one of any of the given
|
|
/// types in the variadic list.
|
|
template <typename T, typename... Ts>
|
|
using is_one_of = disjunction<std::is_same<T, Ts>...>;
|
|
|
|
/// traits class for checking whether type T is a base class for all
|
|
/// the given types in the variadic list.
|
|
template <typename T, typename... Ts>
|
|
using are_base_of = conjunction<std::is_base_of<T, Ts>...>;
|
|
|
|
namespace detail {
|
|
template <typename... Ts> struct Visitor;
|
|
|
|
template <typename HeadT, typename... TailTs>
|
|
struct Visitor<HeadT, TailTs...> : remove_cvref_t<HeadT>, Visitor<TailTs...> {
|
|
explicit constexpr Visitor(HeadT &&Head, TailTs &&...Tail)
|
|
: remove_cvref_t<HeadT>(std::forward<HeadT>(Head)),
|
|
Visitor<TailTs...>(std::forward<TailTs>(Tail)...) {}
|
|
using remove_cvref_t<HeadT>::operator();
|
|
using Visitor<TailTs...>::operator();
|
|
};
|
|
|
|
template <typename HeadT> struct Visitor<HeadT> : remove_cvref_t<HeadT> {
|
|
explicit constexpr Visitor(HeadT &&Head)
|
|
: remove_cvref_t<HeadT>(std::forward<HeadT>(Head)) {}
|
|
using remove_cvref_t<HeadT>::operator();
|
|
};
|
|
} // namespace detail
|
|
|
|
/// Returns an opaquely-typed Callable object whose operator() overload set is
|
|
/// the sum of the operator() overload sets of each CallableT in CallableTs.
|
|
///
|
|
/// The type of the returned object derives from each CallableT in CallableTs.
|
|
/// The returned object is constructed by invoking the appropriate copy or move
|
|
/// constructor of each CallableT, as selected by overload resolution on the
|
|
/// corresponding argument to makeVisitor.
|
|
///
|
|
/// Example:
|
|
///
|
|
/// \code
|
|
/// auto visitor = makeVisitor([](auto) { return "unhandled type"; },
|
|
/// [](int i) { return "int"; },
|
|
/// [](std::string s) { return "str"; });
|
|
/// auto a = visitor(42); // `a` is now "int".
|
|
/// auto b = visitor("foo"); // `b` is now "str".
|
|
/// auto c = visitor(3.14f); // `c` is now "unhandled type".
|
|
/// \endcode
|
|
///
|
|
/// Example of making a visitor with a lambda which captures a move-only type:
|
|
///
|
|
/// \code
|
|
/// std::unique_ptr<FooHandler> FH = /* ... */;
|
|
/// auto visitor = makeVisitor(
|
|
/// [FH{std::move(FH)}](Foo F) { return FH->handle(F); },
|
|
/// [](int i) { return i; },
|
|
/// [](std::string s) { return atoi(s); });
|
|
/// \endcode
|
|
template <typename... CallableTs>
|
|
constexpr decltype(auto) makeVisitor(CallableTs &&...Callables) {
|
|
return detail::Visitor<CallableTs...>(std::forward<CallableTs>(Callables)...);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Extra additions for arrays
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// We have a copy here so that LLVM behaves the same when using different
|
|
// standard libraries.
|
|
template <class Iterator, class RNG>
|
|
void shuffle(Iterator first, Iterator last, RNG &&g) {
|
|
// It would be better to use a std::uniform_int_distribution,
|
|
// but that would be stdlib dependent.
|
|
typedef
|
|
typename std::iterator_traits<Iterator>::difference_type difference_type;
|
|
for (auto size = last - first; size > 1; ++first, (void)--size) {
|
|
difference_type offset = g() % size;
|
|
// Avoid self-assignment due to incorrect assertions in libstdc++
|
|
// containers (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85828).
|
|
if (offset != difference_type(0))
|
|
std::iter_swap(first, first + offset);
|
|
}
|
|
}
|
|
|
|
/// Find the length of an array.
|
|
template <class T, std::size_t N>
|
|
constexpr inline size_t array_lengthof(T (&)[N]) {
|
|
return N;
|
|
}
|
|
|
|
/// Adapt std::less<T> for array_pod_sort.
|
|
template<typename T>
|
|
inline int array_pod_sort_comparator(const void *P1, const void *P2) {
|
|
if (std::less<T>()(*reinterpret_cast<const T*>(P1),
|
|
*reinterpret_cast<const T*>(P2)))
|
|
return -1;
|
|
if (std::less<T>()(*reinterpret_cast<const T*>(P2),
|
|
*reinterpret_cast<const T*>(P1)))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/// get_array_pod_sort_comparator - This is an internal helper function used to
|
|
/// get type deduction of T right.
|
|
template<typename T>
|
|
inline int (*get_array_pod_sort_comparator(const T &))
|
|
(const void*, const void*) {
|
|
return array_pod_sort_comparator<T>;
|
|
}
|
|
|
|
#ifdef EXPENSIVE_CHECKS
|
|
namespace detail {
|
|
|
|
inline unsigned presortShuffleEntropy() {
|
|
static unsigned Result(std::random_device{}());
|
|
return Result;
|
|
}
|
|
|
|
template <class IteratorTy>
|
|
inline void presortShuffle(IteratorTy Start, IteratorTy End) {
|
|
std::mt19937 Generator(presortShuffleEntropy());
|
|
llvm::shuffle(Start, End, Generator);
|
|
}
|
|
|
|
} // end namespace detail
|
|
#endif
|
|
|
|
/// array_pod_sort - This sorts an array with the specified start and end
|
|
/// extent. This is just like std::sort, except that it calls qsort instead of
|
|
/// using an inlined template. qsort is slightly slower than std::sort, but
|
|
/// most sorts are not performance critical in LLVM and std::sort has to be
|
|
/// template instantiated for each type, leading to significant measured code
|
|
/// bloat. This function should generally be used instead of std::sort where
|
|
/// possible.
|
|
///
|
|
/// This function assumes that you have simple POD-like types that can be
|
|
/// compared with std::less and can be moved with memcpy. If this isn't true,
|
|
/// you should use std::sort.
|
|
///
|
|
/// NOTE: If qsort_r were portable, we could allow a custom comparator and
|
|
/// default to std::less.
|
|
template<class IteratorTy>
|
|
inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
|
|
// Don't inefficiently call qsort with one element or trigger undefined
|
|
// behavior with an empty sequence.
|
|
auto NElts = End - Start;
|
|
if (NElts <= 1) return;
|
|
#ifdef EXPENSIVE_CHECKS
|
|
detail::presortShuffle<IteratorTy>(Start, End);
|
|
#endif
|
|
qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
|
|
}
|
|
|
|
template <class IteratorTy>
|
|
inline void array_pod_sort(
|
|
IteratorTy Start, IteratorTy End,
|
|
int (*Compare)(
|
|
const typename std::iterator_traits<IteratorTy>::value_type *,
|
|
const typename std::iterator_traits<IteratorTy>::value_type *)) {
|
|
// Don't inefficiently call qsort with one element or trigger undefined
|
|
// behavior with an empty sequence.
|
|
auto NElts = End - Start;
|
|
if (NElts <= 1) return;
|
|
#ifdef EXPENSIVE_CHECKS
|
|
detail::presortShuffle<IteratorTy>(Start, End);
|
|
#endif
|
|
qsort(&*Start, NElts, sizeof(*Start),
|
|
reinterpret_cast<int (*)(const void *, const void *)>(Compare));
|
|
}
|
|
|
|
namespace detail {
|
|
template <typename T>
|
|
// We can use qsort if the iterator type is a pointer and the underlying value
|
|
// is trivially copyable.
|
|
using sort_trivially_copyable = conjunction<
|
|
std::is_pointer<T>,
|
|
std::is_trivially_copyable<typename std::iterator_traits<T>::value_type>>;
|
|
} // namespace detail
|
|
|
|
// Provide wrappers to std::sort which shuffle the elements before sorting
|
|
// to help uncover non-deterministic behavior (PR35135).
|
|
template <typename IteratorTy,
|
|
std::enable_if_t<!detail::sort_trivially_copyable<IteratorTy>::value,
|
|
int> = 0>
|
|
inline void sort(IteratorTy Start, IteratorTy End) {
|
|
#ifdef EXPENSIVE_CHECKS
|
|
detail::presortShuffle<IteratorTy>(Start, End);
|
|
#endif
|
|
std::sort(Start, End);
|
|
}
|
|
|
|
// Forward trivially copyable types to array_pod_sort. This avoids a large
|
|
// amount of code bloat for a minor performance hit.
|
|
template <typename IteratorTy,
|
|
std::enable_if_t<detail::sort_trivially_copyable<IteratorTy>::value,
|
|
int> = 0>
|
|
inline void sort(IteratorTy Start, IteratorTy End) {
|
|
array_pod_sort(Start, End);
|
|
}
|
|
|
|
template <typename Container> inline void sort(Container &&C) {
|
|
llvm::sort(adl_begin(C), adl_end(C));
|
|
}
|
|
|
|
template <typename IteratorTy, typename Compare>
|
|
inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
|
|
#ifdef EXPENSIVE_CHECKS
|
|
detail::presortShuffle<IteratorTy>(Start, End);
|
|
#endif
|
|
std::sort(Start, End, Comp);
|
|
}
|
|
|
|
template <typename Container, typename Compare>
|
|
inline void sort(Container &&C, Compare Comp) {
|
|
llvm::sort(adl_begin(C), adl_end(C), Comp);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Extra additions to <algorithm>
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// Get the size of a range. This is a wrapper function around std::distance
|
|
/// which is only enabled when the operation is O(1).
|
|
template <typename R>
|
|
auto size(R &&Range,
|
|
std::enable_if_t<
|
|
std::is_base_of<std::random_access_iterator_tag,
|
|
typename std::iterator_traits<decltype(
|
|
Range.begin())>::iterator_category>::value,
|
|
void> * = nullptr) {
|
|
return std::distance(Range.begin(), Range.end());
|
|
}
|
|
|
|
/// Provide wrappers to std::for_each which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename UnaryFunction>
|
|
UnaryFunction for_each(R &&Range, UnaryFunction F) {
|
|
return std::for_each(adl_begin(Range), adl_end(Range), F);
|
|
}
|
|
|
|
/// Provide wrappers to std::all_of which take ranges instead of having to pass
|
|
/// begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
bool all_of(R &&Range, UnaryPredicate P) {
|
|
return std::all_of(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::any_of which take ranges instead of having to pass
|
|
/// begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
bool any_of(R &&Range, UnaryPredicate P) {
|
|
return std::any_of(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::none_of which take ranges instead of having to pass
|
|
/// begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
bool none_of(R &&Range, UnaryPredicate P) {
|
|
return std::none_of(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::find which take ranges instead of having to pass
|
|
/// begin/end explicitly.
|
|
template <typename R, typename T> auto find(R &&Range, const T &Val) {
|
|
return std::find(adl_begin(Range), adl_end(Range), Val);
|
|
}
|
|
|
|
/// Provide wrappers to std::find_if which take ranges instead of having to pass
|
|
/// begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
auto find_if(R &&Range, UnaryPredicate P) {
|
|
return std::find_if(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
template <typename R, typename UnaryPredicate>
|
|
auto find_if_not(R &&Range, UnaryPredicate P) {
|
|
return std::find_if_not(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::remove_if which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
auto remove_if(R &&Range, UnaryPredicate P) {
|
|
return std::remove_if(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::copy_if which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename OutputIt, typename UnaryPredicate>
|
|
OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
|
|
return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
|
|
}
|
|
|
|
template <typename R, typename OutputIt>
|
|
OutputIt copy(R &&Range, OutputIt Out) {
|
|
return std::copy(adl_begin(Range), adl_end(Range), Out);
|
|
}
|
|
|
|
/// Provide wrappers to std::move which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename OutputIt>
|
|
OutputIt move(R &&Range, OutputIt Out) {
|
|
return std::move(adl_begin(Range), adl_end(Range), Out);
|
|
}
|
|
|
|
/// Wrapper function around std::find to detect if an element exists
|
|
/// in a container.
|
|
template <typename R, typename E>
|
|
bool is_contained(R &&Range, const E &Element) {
|
|
return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
|
|
}
|
|
|
|
/// Wrapper function around std::is_sorted to check if elements in a range \p R
|
|
/// are sorted with respect to a comparator \p C.
|
|
template <typename R, typename Compare> bool is_sorted(R &&Range, Compare C) {
|
|
return std::is_sorted(adl_begin(Range), adl_end(Range), C);
|
|
}
|
|
|
|
/// Wrapper function around std::is_sorted to check if elements in a range \p R
|
|
/// are sorted in non-descending order.
|
|
template <typename R> bool is_sorted(R &&Range) {
|
|
return std::is_sorted(adl_begin(Range), adl_end(Range));
|
|
}
|
|
|
|
/// Wrapper function around std::count to count the number of times an element
|
|
/// \p Element occurs in the given range \p Range.
|
|
template <typename R, typename E> auto count(R &&Range, const E &Element) {
|
|
return std::count(adl_begin(Range), adl_end(Range), Element);
|
|
}
|
|
|
|
/// Wrapper function around std::count_if to count the number of times an
|
|
/// element satisfying a given predicate occurs in a range.
|
|
template <typename R, typename UnaryPredicate>
|
|
auto count_if(R &&Range, UnaryPredicate P) {
|
|
return std::count_if(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Wrapper function around std::transform to apply a function to a range and
|
|
/// store the result elsewhere.
|
|
template <typename R, typename OutputIt, typename UnaryFunction>
|
|
OutputIt transform(R &&Range, OutputIt d_first, UnaryFunction F) {
|
|
return std::transform(adl_begin(Range), adl_end(Range), d_first, F);
|
|
}
|
|
|
|
/// Provide wrappers to std::partition which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename UnaryPredicate>
|
|
auto partition(R &&Range, UnaryPredicate P) {
|
|
return std::partition(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
/// Provide wrappers to std::lower_bound which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename T> auto lower_bound(R &&Range, T &&Value) {
|
|
return std::lower_bound(adl_begin(Range), adl_end(Range),
|
|
std::forward<T>(Value));
|
|
}
|
|
|
|
template <typename R, typename T, typename Compare>
|
|
auto lower_bound(R &&Range, T &&Value, Compare C) {
|
|
return std::lower_bound(adl_begin(Range), adl_end(Range),
|
|
std::forward<T>(Value), C);
|
|
}
|
|
|
|
/// Provide wrappers to std::upper_bound which take ranges instead of having to
|
|
/// pass begin/end explicitly.
|
|
template <typename R, typename T> auto upper_bound(R &&Range, T &&Value) {
|
|
return std::upper_bound(adl_begin(Range), adl_end(Range),
|
|
std::forward<T>(Value));
|
|
}
|
|
|
|
template <typename R, typename T, typename Compare>
|
|
auto upper_bound(R &&Range, T &&Value, Compare C) {
|
|
return std::upper_bound(adl_begin(Range), adl_end(Range),
|
|
std::forward<T>(Value), C);
|
|
}
|
|
|
|
template <typename R>
|
|
void stable_sort(R &&Range) {
|
|
std::stable_sort(adl_begin(Range), adl_end(Range));
|
|
}
|
|
|
|
template <typename R, typename Compare>
|
|
void stable_sort(R &&Range, Compare C) {
|
|
std::stable_sort(adl_begin(Range), adl_end(Range), C);
|
|
}
|
|
|
|
/// Binary search for the first iterator in a range where a predicate is false.
|
|
/// Requires that C is always true below some limit, and always false above it.
|
|
template <typename R, typename Predicate,
|
|
typename Val = decltype(*adl_begin(std::declval<R>()))>
|
|
auto partition_point(R &&Range, Predicate P) {
|
|
return std::partition_point(adl_begin(Range), adl_end(Range), P);
|
|
}
|
|
|
|
template<typename Range, typename Predicate>
|
|
auto unique(Range &&R, Predicate P) {
|
|
return std::unique(adl_begin(R), adl_end(R), P);
|
|
}
|
|
|
|
/// Wrapper function around std::equal to detect if all elements
|
|
/// in a container are same.
|
|
template <typename R>
|
|
bool is_splat(R &&Range) {
|
|
size_t range_size = size(Range);
|
|
return range_size != 0 && (range_size == 1 ||
|
|
std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
|
|
}
|
|
|
|
/// Provide a container algorithm similar to C++ Library Fundamentals v2's
|
|
/// `erase_if` which is equivalent to:
|
|
///
|
|
/// C.erase(remove_if(C, pred), C.end());
|
|
///
|
|
/// This version works for any container with an erase method call accepting
|
|
/// two iterators.
|
|
template <typename Container, typename UnaryPredicate>
|
|
void erase_if(Container &C, UnaryPredicate P) {
|
|
C.erase(remove_if(C, P), C.end());
|
|
}
|
|
|
|
/// Wrapper function to remove a value from a container:
|
|
///
|
|
/// C.erase(remove(C.begin(), C.end(), V), C.end());
|
|
template <typename Container, typename ValueType>
|
|
void erase_value(Container &C, ValueType V) {
|
|
C.erase(std::remove(C.begin(), C.end(), V), C.end());
|
|
}
|
|
|
|
/// Wrapper function to append a range to a container.
|
|
///
|
|
/// C.insert(C.end(), R.begin(), R.end());
|
|
template <typename Container, typename Range>
|
|
inline void append_range(Container &C, Range &&R) {
|
|
C.insert(C.end(), R.begin(), R.end());
|
|
}
|
|
|
|
/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
|
|
/// the range [ValIt, ValEnd) (which is not from the same container).
|
|
template<typename Container, typename RandomAccessIterator>
|
|
void replace(Container &Cont, typename Container::iterator ContIt,
|
|
typename Container::iterator ContEnd, RandomAccessIterator ValIt,
|
|
RandomAccessIterator ValEnd) {
|
|
while (true) {
|
|
if (ValIt == ValEnd) {
|
|
Cont.erase(ContIt, ContEnd);
|
|
return;
|
|
} else if (ContIt == ContEnd) {
|
|
Cont.insert(ContIt, ValIt, ValEnd);
|
|
return;
|
|
}
|
|
*ContIt++ = *ValIt++;
|
|
}
|
|
}
|
|
|
|
/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
|
|
/// the range R.
|
|
template<typename Container, typename Range = std::initializer_list<
|
|
typename Container::value_type>>
|
|
void replace(Container &Cont, typename Container::iterator ContIt,
|
|
typename Container::iterator ContEnd, Range R) {
|
|
replace(Cont, ContIt, ContEnd, R.begin(), R.end());
|
|
}
|
|
|
|
/// An STL-style algorithm similar to std::for_each that applies a second
|
|
/// functor between every pair of elements.
|
|
///
|
|
/// This provides the control flow logic to, for example, print a
|
|
/// comma-separated list:
|
|
/// \code
|
|
/// interleave(names.begin(), names.end(),
|
|
/// [&](StringRef name) { os << name; },
|
|
/// [&] { os << ", "; });
|
|
/// \endcode
|
|
template <typename ForwardIterator, typename UnaryFunctor,
|
|
typename NullaryFunctor,
|
|
typename = typename std::enable_if<
|
|
!std::is_constructible<StringRef, UnaryFunctor>::value &&
|
|
!std::is_constructible<StringRef, NullaryFunctor>::value>::type>
|
|
inline void interleave(ForwardIterator begin, ForwardIterator end,
|
|
UnaryFunctor each_fn, NullaryFunctor between_fn) {
|
|
if (begin == end)
|
|
return;
|
|
each_fn(*begin);
|
|
++begin;
|
|
for (; begin != end; ++begin) {
|
|
between_fn();
|
|
each_fn(*begin);
|
|
}
|
|
}
|
|
|
|
template <typename Container, typename UnaryFunctor, typename NullaryFunctor,
|
|
typename = typename std::enable_if<
|
|
!std::is_constructible<StringRef, UnaryFunctor>::value &&
|
|
!std::is_constructible<StringRef, NullaryFunctor>::value>::type>
|
|
inline void interleave(const Container &c, UnaryFunctor each_fn,
|
|
NullaryFunctor between_fn) {
|
|
interleave(c.begin(), c.end(), each_fn, between_fn);
|
|
}
|
|
|
|
/// Overload of interleave for the common case of string separator.
|
|
template <typename Container, typename UnaryFunctor, typename StreamT,
|
|
typename T = detail::ValueOfRange<Container>>
|
|
inline void interleave(const Container &c, StreamT &os, UnaryFunctor each_fn,
|
|
const StringRef &separator) {
|
|
interleave(c.begin(), c.end(), each_fn, [&] { os << separator; });
|
|
}
|
|
template <typename Container, typename StreamT,
|
|
typename T = detail::ValueOfRange<Container>>
|
|
inline void interleave(const Container &c, StreamT &os,
|
|
const StringRef &separator) {
|
|
interleave(
|
|
c, os, [&](const T &a) { os << a; }, separator);
|
|
}
|
|
|
|
template <typename Container, typename UnaryFunctor, typename StreamT,
|
|
typename T = detail::ValueOfRange<Container>>
|
|
inline void interleaveComma(const Container &c, StreamT &os,
|
|
UnaryFunctor each_fn) {
|
|
interleave(c, os, each_fn, ", ");
|
|
}
|
|
template <typename Container, typename StreamT,
|
|
typename T = detail::ValueOfRange<Container>>
|
|
inline void interleaveComma(const Container &c, StreamT &os) {
|
|
interleaveComma(c, os, [&](const T &a) { os << a; });
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Extra additions to <memory>
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
struct FreeDeleter {
|
|
void operator()(void* v) {
|
|
::free(v);
|
|
}
|
|
};
|
|
|
|
template<typename First, typename Second>
|
|
struct pair_hash {
|
|
size_t operator()(const std::pair<First, Second> &P) const {
|
|
return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
|
|
}
|
|
};
|
|
|
|
/// Binary functor that adapts to any other binary functor after dereferencing
|
|
/// operands.
|
|
template <typename T> struct deref {
|
|
T func;
|
|
|
|
// Could be further improved to cope with non-derivable functors and
|
|
// non-binary functors (should be a variadic template member function
|
|
// operator()).
|
|
template <typename A, typename B> auto operator()(A &lhs, B &rhs) const {
|
|
assert(lhs);
|
|
assert(rhs);
|
|
return func(*lhs, *rhs);
|
|
}
|
|
};
|
|
|
|
namespace detail {
|
|
|
|
template <typename R> class enumerator_iter;
|
|
|
|
template <typename R> struct result_pair {
|
|
using value_reference =
|
|
typename std::iterator_traits<IterOfRange<R>>::reference;
|
|
|
|
friend class enumerator_iter<R>;
|
|
|
|
result_pair() = default;
|
|
result_pair(std::size_t Index, IterOfRange<R> Iter)
|
|
: Index(Index), Iter(Iter) {}
|
|
|
|
result_pair(const result_pair<R> &Other)
|
|
: Index(Other.Index), Iter(Other.Iter) {}
|
|
result_pair &operator=(const result_pair &Other) {
|
|
Index = Other.Index;
|
|
Iter = Other.Iter;
|
|
return *this;
|
|
}
|
|
|
|
std::size_t index() const { return Index; }
|
|
const value_reference value() const { return *Iter; }
|
|
value_reference value() { return *Iter; }
|
|
|
|
private:
|
|
std::size_t Index = std::numeric_limits<std::size_t>::max();
|
|
IterOfRange<R> Iter;
|
|
};
|
|
|
|
template <typename R>
|
|
class enumerator_iter
|
|
: public iterator_facade_base<
|
|
enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
|
|
typename std::iterator_traits<IterOfRange<R>>::difference_type,
|
|
typename std::iterator_traits<IterOfRange<R>>::pointer,
|
|
typename std::iterator_traits<IterOfRange<R>>::reference> {
|
|
using result_type = result_pair<R>;
|
|
|
|
public:
|
|
explicit enumerator_iter(IterOfRange<R> EndIter)
|
|
: Result(std::numeric_limits<size_t>::max(), EndIter) {}
|
|
|
|
enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
|
|
: Result(Index, Iter) {}
|
|
|
|
result_type &operator*() { return Result; }
|
|
const result_type &operator*() const { return Result; }
|
|
|
|
enumerator_iter &operator++() {
|
|
assert(Result.Index != std::numeric_limits<size_t>::max());
|
|
++Result.Iter;
|
|
++Result.Index;
|
|
return *this;
|
|
}
|
|
|
|
bool operator==(const enumerator_iter &RHS) const {
|
|
// Don't compare indices here, only iterators. It's possible for an end
|
|
// iterator to have different indices depending on whether it was created
|
|
// by calling std::end() versus incrementing a valid iterator.
|
|
return Result.Iter == RHS.Result.Iter;
|
|
}
|
|
|
|
enumerator_iter(const enumerator_iter &Other) : Result(Other.Result) {}
|
|
enumerator_iter &operator=(const enumerator_iter &Other) {
|
|
Result = Other.Result;
|
|
return *this;
|
|
}
|
|
|
|
private:
|
|
result_type Result;
|
|
};
|
|
|
|
template <typename R> class enumerator {
|
|
public:
|
|
explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
|
|
|
|
enumerator_iter<R> begin() {
|
|
return enumerator_iter<R>(0, std::begin(TheRange));
|
|
}
|
|
|
|
enumerator_iter<R> end() {
|
|
return enumerator_iter<R>(std::end(TheRange));
|
|
}
|
|
|
|
private:
|
|
R TheRange;
|
|
};
|
|
|
|
} // end namespace detail
|
|
|
|
/// Given an input range, returns a new range whose values are are pair (A,B)
|
|
/// such that A is the 0-based index of the item in the sequence, and B is
|
|
/// the value from the original sequence. Example:
|
|
///
|
|
/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
|
|
/// for (auto X : enumerate(Items)) {
|
|
/// printf("Item %d - %c\n", X.index(), X.value());
|
|
/// }
|
|
///
|
|
/// Output:
|
|
/// Item 0 - A
|
|
/// Item 1 - B
|
|
/// Item 2 - C
|
|
/// Item 3 - D
|
|
///
|
|
template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
|
|
return detail::enumerator<R>(std::forward<R>(TheRange));
|
|
}
|
|
|
|
namespace detail {
|
|
|
|
template <typename F, typename Tuple, std::size_t... I>
|
|
decltype(auto) apply_tuple_impl(F &&f, Tuple &&t, std::index_sequence<I...>) {
|
|
return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
|
|
}
|
|
|
|
} // end namespace detail
|
|
|
|
/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
|
|
/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
|
|
/// return the result.
|
|
template <typename F, typename Tuple>
|
|
decltype(auto) apply_tuple(F &&f, Tuple &&t) {
|
|
using Indices = std::make_index_sequence<
|
|
std::tuple_size<typename std::decay<Tuple>::type>::value>;
|
|
|
|
return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
|
|
Indices{});
|
|
}
|
|
|
|
/// Return true if the sequence [Begin, End) has exactly N items. Runs in O(N)
|
|
/// time. Not meant for use with random-access iterators.
|
|
/// Can optionally take a predicate to filter lazily some items.
|
|
template <typename IterTy,
|
|
typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
|
|
bool hasNItems(
|
|
IterTy &&Begin, IterTy &&End, unsigned N,
|
|
Pred &&ShouldBeCounted =
|
|
[](const decltype(*std::declval<IterTy>()) &) { return true; },
|
|
std::enable_if_t<
|
|
!std::is_base_of<std::random_access_iterator_tag,
|
|
typename std::iterator_traits<std::remove_reference_t<
|
|
decltype(Begin)>>::iterator_category>::value,
|
|
void> * = nullptr) {
|
|
for (; N; ++Begin) {
|
|
if (Begin == End)
|
|
return false; // Too few.
|
|
N -= ShouldBeCounted(*Begin);
|
|
}
|
|
for (; Begin != End; ++Begin)
|
|
if (ShouldBeCounted(*Begin))
|
|
return false; // Too many.
|
|
return true;
|
|
}
|
|
|
|
/// Return true if the sequence [Begin, End) has N or more items. Runs in O(N)
|
|
/// time. Not meant for use with random-access iterators.
|
|
/// Can optionally take a predicate to lazily filter some items.
|
|
template <typename IterTy,
|
|
typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
|
|
bool hasNItemsOrMore(
|
|
IterTy &&Begin, IterTy &&End, unsigned N,
|
|
Pred &&ShouldBeCounted =
|
|
[](const decltype(*std::declval<IterTy>()) &) { return true; },
|
|
std::enable_if_t<
|
|
!std::is_base_of<std::random_access_iterator_tag,
|
|
typename std::iterator_traits<std::remove_reference_t<
|
|
decltype(Begin)>>::iterator_category>::value,
|
|
void> * = nullptr) {
|
|
for (; N; ++Begin) {
|
|
if (Begin == End)
|
|
return false; // Too few.
|
|
N -= ShouldBeCounted(*Begin);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/// Returns true if the sequence [Begin, End) has N or less items. Can
|
|
/// optionally take a predicate to lazily filter some items.
|
|
template <typename IterTy,
|
|
typename Pred = bool (*)(const decltype(*std::declval<IterTy>()) &)>
|
|
bool hasNItemsOrLess(
|
|
IterTy &&Begin, IterTy &&End, unsigned N,
|
|
Pred &&ShouldBeCounted = [](const decltype(*std::declval<IterTy>()) &) {
|
|
return true;
|
|
}) {
|
|
assert(N != std::numeric_limits<unsigned>::max());
|
|
return !hasNItemsOrMore(Begin, End, N + 1, ShouldBeCounted);
|
|
}
|
|
|
|
/// Returns true if the given container has exactly N items
|
|
template <typename ContainerTy> bool hasNItems(ContainerTy &&C, unsigned N) {
|
|
return hasNItems(std::begin(C), std::end(C), N);
|
|
}
|
|
|
|
/// Returns true if the given container has N or more items
|
|
template <typename ContainerTy>
|
|
bool hasNItemsOrMore(ContainerTy &&C, unsigned N) {
|
|
return hasNItemsOrMore(std::begin(C), std::end(C), N);
|
|
}
|
|
|
|
/// Returns true if the given container has N or less items
|
|
template <typename ContainerTy>
|
|
bool hasNItemsOrLess(ContainerTy &&C, unsigned N) {
|
|
return hasNItemsOrLess(std::begin(C), std::end(C), N);
|
|
}
|
|
|
|
/// Returns a raw pointer that represents the same address as the argument.
|
|
///
|
|
/// This implementation can be removed once we move to C++20 where it's defined
|
|
/// as std::to_address().
|
|
///
|
|
/// The std::pointer_traits<>::to_address(p) variations of these overloads has
|
|
/// not been implemented.
|
|
template <class Ptr> auto to_address(const Ptr &P) { return P.operator->(); }
|
|
template <class T> constexpr T *to_address(T *P) { return P; }
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif // LLVM_ADT_STLEXTRAS_H
|