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author | vitalyisaev <vitalyisaev@yandex-team.com> | 2023-06-29 10:00:50 +0300 |
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committer | vitalyisaev <vitalyisaev@yandex-team.com> | 2023-06-29 10:00:50 +0300 |
commit | 6ffe9e53658409f212834330e13564e4952558f6 (patch) | |
tree | 85b1e00183517648b228aafa7c8fb07f5276f419 /contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h | |
parent | 726057070f9c5a91fc10fde0d5024913d10f1ab9 (diff) | |
download | ydb-6ffe9e53658409f212834330e13564e4952558f6.tar.gz |
YQ Connector: support managed ClickHouse
Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.
Diffstat (limited to 'contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h')
-rw-r--r-- | contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h b/contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h new file mode 100644 index 0000000000..a91823d845 --- /dev/null +++ b/contrib/libs/llvm14/include/llvm/ADT/BreadthFirstIterator.h @@ -0,0 +1,175 @@ +#pragma once + +#ifdef __GNUC__ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wunused-parameter" +#endif + +//===- llvm/ADT/BreadthFirstIterator.h - Breadth First iterator -*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +/// +/// \file +/// This file builds on the ADT/GraphTraits.h file to build a generic breadth +/// first graph iterator. This file exposes the following functions/types: +/// +/// bf_begin/bf_end/bf_iterator +/// * Normal breadth-first iteration - visit a graph level-by-level. +/// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_ADT_BREADTHFIRSTITERATOR_H +#define LLVM_ADT_BREADTHFIRSTITERATOR_H + +#include "llvm/ADT/GraphTraits.h" +#include "llvm/ADT/None.h" +#include "llvm/ADT/Optional.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/iterator_range.h" +#include <iterator> +#include <queue> +#include <utility> + +namespace llvm { + +// bf_iterator_storage - A private class which is used to figure out where to +// store the visited set. We only provide a non-external variant for now. +template <class SetType> class bf_iterator_storage { +public: + SetType Visited; +}; + +// The visited state for the iteration is a simple set. +template <typename NodeRef, unsigned SmallSize = 8> +using bf_iterator_default_set = SmallPtrSet<NodeRef, SmallSize>; + +// Generic Breadth first search iterator. +template <class GraphT, + class SetType = + bf_iterator_default_set<typename GraphTraits<GraphT>::NodeRef>, + class GT = GraphTraits<GraphT>> +class bf_iterator : public bf_iterator_storage<SetType> { +public: + using iterator_category = std::forward_iterator_tag; + using value_type = typename GT::NodeRef; + using difference_type = std::ptrdiff_t; + using pointer = value_type *; + using reference = value_type &; + +private: + using NodeRef = typename GT::NodeRef; + using ChildItTy = typename GT::ChildIteratorType; + + // First element is the node reference, second is the next child to visit. + using QueueElement = std::pair<NodeRef, Optional<ChildItTy>>; + + // Visit queue - used to maintain BFS ordering. + // Optional<> because we need markers for levels. + std::queue<Optional<QueueElement>> VisitQueue; + + // Current level. + unsigned Level = 0; + + inline bf_iterator(NodeRef Node) { + this->Visited.insert(Node); + Level = 0; + + // Also, insert a dummy node as marker. + VisitQueue.push(QueueElement(Node, None)); + VisitQueue.push(None); + } + + inline bf_iterator() = default; + + inline void toNext() { + Optional<QueueElement> Head = VisitQueue.front(); + QueueElement H = Head.getValue(); + NodeRef Node = H.first; + Optional<ChildItTy> &ChildIt = H.second; + + if (!ChildIt) + ChildIt.emplace(GT::child_begin(Node)); + while (*ChildIt != GT::child_end(Node)) { + NodeRef Next = *(*ChildIt)++; + + // Already visited? + if (this->Visited.insert(Next).second) + VisitQueue.push(QueueElement(Next, None)); + } + VisitQueue.pop(); + + // Go to the next element skipping markers if needed. + if (!VisitQueue.empty()) { + Head = VisitQueue.front(); + if (Head != None) + return; + Level += 1; + VisitQueue.pop(); + + // Don't push another marker if this is the last + // element. + if (!VisitQueue.empty()) + VisitQueue.push(None); + } + } + +public: + // Provide static begin and end methods as our public "constructors" + static bf_iterator begin(const GraphT &G) { + return bf_iterator(GT::getEntryNode(G)); + } + + static bf_iterator end(const GraphT &G) { return bf_iterator(); } + + bool operator==(const bf_iterator &RHS) const { + return VisitQueue == RHS.VisitQueue; + } + + bool operator!=(const bf_iterator &RHS) const { return !(*this == RHS); } + + const NodeRef &operator*() const { return VisitQueue.front()->first; } + + // This is a nonstandard operator-> that dereferences the pointer an extra + // time so that you can actually call methods on the node, because the + // contained type is a pointer. + NodeRef operator->() const { return **this; } + + bf_iterator &operator++() { // Pre-increment + toNext(); + return *this; + } + + bf_iterator operator++(int) { // Post-increment + bf_iterator ItCopy = *this; + ++*this; + return ItCopy; + } + + unsigned getLevel() const { return Level; } +}; + +// Provide global constructors that automatically figure out correct types. +template <class T> bf_iterator<T> bf_begin(const T &G) { + return bf_iterator<T>::begin(G); +} + +template <class T> bf_iterator<T> bf_end(const T &G) { + return bf_iterator<T>::end(G); +} + +// Provide an accessor method to use them in range-based patterns. +template <class T> iterator_range<bf_iterator<T>> breadth_first(const T &G) { + return make_range(bf_begin(G), bf_end(G)); +} + +} // end namespace llvm + +#endif // LLVM_ADT_BREADTHFIRSTITERATOR_H + +#ifdef __GNUC__ +#pragma GCC diagnostic pop +#endif |