Abseil Common Libraries (C++) (grcp 依赖)
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704 lines
20 KiB
704 lines
20 KiB
// Copyright 2017 The Abseil Authors. |
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// |
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// Licensed under the Apache License, Version 2.0 (the "License"); |
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// you may not use this file except in compliance with the License. |
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// You may obtain a copy of the License at |
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// |
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// https://www.apache.org/licenses/LICENSE-2.0 |
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// |
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// Unless required by applicable law or agreed to in writing, software |
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// distributed under the License is distributed on an "AS IS" BASIS, |
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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// See the License for the specific language governing permissions and |
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// limitations under the License. |
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// GraphCycles provides incremental cycle detection on a dynamic |
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// graph using the following algorithm: |
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// |
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// A dynamic topological sort algorithm for directed acyclic graphs |
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// David J. Pearce, Paul H. J. Kelly |
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// Journal of Experimental Algorithmics (JEA) JEA Homepage archive |
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// Volume 11, 2006, Article No. 1.7 |
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// |
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// Brief summary of the algorithm: |
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// |
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// (1) Maintain a rank for each node that is consistent |
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// with the topological sort of the graph. I.e., path from x to y |
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// implies rank[x] < rank[y]. |
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// (2) When a new edge (x->y) is inserted, do nothing if rank[x] < rank[y]. |
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// (3) Otherwise: adjust ranks in the neighborhood of x and y. |
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#include "absl/base/attributes.h" |
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// This file is a no-op if the required LowLevelAlloc support is missing. |
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#include "absl/base/internal/low_level_alloc.h" |
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#ifndef ABSL_LOW_LEVEL_ALLOC_MISSING |
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#include "absl/synchronization/internal/graphcycles.h" |
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#include <algorithm> |
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#include <array> |
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#include <limits> |
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#include "absl/base/internal/hide_ptr.h" |
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#include "absl/base/internal/raw_logging.h" |
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#include "absl/base/internal/spinlock.h" |
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// Do not use STL. This module does not use standard memory allocation. |
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namespace absl { |
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ABSL_NAMESPACE_BEGIN |
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namespace synchronization_internal { |
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namespace { |
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// Avoid LowLevelAlloc's default arena since it calls malloc hooks in |
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// which people are doing things like acquiring Mutexes. |
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ABSL_CONST_INIT static absl::base_internal::SpinLock arena_mu( |
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absl::kConstInit, base_internal::SCHEDULE_KERNEL_ONLY); |
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ABSL_CONST_INIT static base_internal::LowLevelAlloc::Arena* arena; |
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static void InitArenaIfNecessary() { |
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arena_mu.Lock(); |
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if (arena == nullptr) { |
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arena = base_internal::LowLevelAlloc::NewArena(0); |
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} |
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arena_mu.Unlock(); |
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} |
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// Number of inlined elements in Vec. Hash table implementation |
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// relies on this being a power of two. |
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static const uint32_t kInline = 8; |
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// A simple LowLevelAlloc based resizable vector with inlined storage |
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// for a few elements. T must be a plain type since constructor |
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// and destructor are not run on elements of type T managed by Vec. |
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template <typename T> |
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class Vec { |
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public: |
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Vec() { Init(); } |
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~Vec() { Discard(); } |
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void clear() { |
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Discard(); |
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Init(); |
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} |
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bool empty() const { return size_ == 0; } |
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uint32_t size() const { return size_; } |
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T* begin() { return ptr_; } |
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T* end() { return ptr_ + size_; } |
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const T& operator[](uint32_t i) const { return ptr_[i]; } |
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T& operator[](uint32_t i) { return ptr_[i]; } |
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const T& back() const { return ptr_[size_-1]; } |
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void pop_back() { size_--; } |
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void push_back(const T& v) { |
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if (size_ == capacity_) Grow(size_ + 1); |
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ptr_[size_] = v; |
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size_++; |
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} |
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void resize(uint32_t n) { |
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if (n > capacity_) Grow(n); |
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size_ = n; |
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} |
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void fill(const T& val) { |
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for (uint32_t i = 0; i < size(); i++) { |
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ptr_[i] = val; |
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} |
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} |
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// Guarantees src is empty at end. |
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// Provided for the hash table resizing code below. |
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void MoveFrom(Vec<T>* src) { |
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if (src->ptr_ == src->space_) { |
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// Need to actually copy |
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resize(src->size_); |
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std::copy(src->ptr_, src->ptr_ + src->size_, ptr_); |
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src->size_ = 0; |
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} else { |
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Discard(); |
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ptr_ = src->ptr_; |
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size_ = src->size_; |
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capacity_ = src->capacity_; |
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src->Init(); |
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} |
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} |
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private: |
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T* ptr_; |
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T space_[kInline]; |
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uint32_t size_; |
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uint32_t capacity_; |
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void Init() { |
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ptr_ = space_; |
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size_ = 0; |
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capacity_ = kInline; |
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} |
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void Discard() { |
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if (ptr_ != space_) base_internal::LowLevelAlloc::Free(ptr_); |
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} |
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void Grow(uint32_t n) { |
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while (capacity_ < n) { |
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capacity_ *= 2; |
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} |
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size_t request = static_cast<size_t>(capacity_) * sizeof(T); |
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T* copy = static_cast<T*>( |
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base_internal::LowLevelAlloc::AllocWithArena(request, arena)); |
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std::copy(ptr_, ptr_ + size_, copy); |
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Discard(); |
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ptr_ = copy; |
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} |
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Vec(const Vec&) = delete; |
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Vec& operator=(const Vec&) = delete; |
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}; |
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// A hash set of non-negative int32_t that uses Vec for its underlying storage. |
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class NodeSet { |
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public: |
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NodeSet() { Init(); } |
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void clear() { Init(); } |
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bool contains(int32_t v) const { return table_[FindIndex(v)] == v; } |
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bool insert(int32_t v) { |
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uint32_t i = FindIndex(v); |
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if (table_[i] == v) { |
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return false; |
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} |
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if (table_[i] == kEmpty) { |
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// Only inserting over an empty cell increases the number of occupied |
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// slots. |
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occupied_++; |
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} |
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table_[i] = v; |
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// Double when 75% full. |
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if (occupied_ >= table_.size() - table_.size()/4) Grow(); |
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return true; |
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} |
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void erase(int32_t v) { |
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uint32_t i = FindIndex(v); |
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if (table_[i] == v) { |
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table_[i] = kDel; |
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} |
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} |
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// Iteration: is done via HASH_FOR_EACH |
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// Example: |
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// HASH_FOR_EACH(elem, node->out) { ... } |
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#define HASH_FOR_EACH(elem, eset) \ |
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for (int32_t elem, _cursor = 0; (eset).Next(&_cursor, &elem); ) |
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bool Next(int32_t* cursor, int32_t* elem) { |
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while (static_cast<uint32_t>(*cursor) < table_.size()) { |
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int32_t v = table_[static_cast<uint32_t>(*cursor)]; |
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(*cursor)++; |
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if (v >= 0) { |
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*elem = v; |
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return true; |
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} |
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} |
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return false; |
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} |
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private: |
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enum : int32_t { kEmpty = -1, kDel = -2 }; |
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Vec<int32_t> table_; |
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uint32_t occupied_; // Count of non-empty slots (includes deleted slots) |
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static uint32_t Hash(int32_t a) { return static_cast<uint32_t>(a * 41); } |
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// Return index for storing v. May return an empty index or deleted index |
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uint32_t FindIndex(int32_t v) const { |
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// Search starting at hash index. |
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const uint32_t mask = table_.size() - 1; |
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uint32_t i = Hash(v) & mask; |
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uint32_t deleted_index = 0; // index of first deleted element we see |
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bool seen_deleted_element = false; |
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while (true) { |
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int32_t e = table_[i]; |
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if (v == e) { |
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return i; |
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} else if (e == kEmpty) { |
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// Return any previously encountered deleted slot. |
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return seen_deleted_element ? deleted_index : i; |
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} else if (e == kDel && !seen_deleted_element) { |
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// Keep searching since v might be present later. |
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deleted_index = i; |
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seen_deleted_element = true; |
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} |
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i = (i + 1) & mask; // Linear probing; quadratic is slightly slower. |
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} |
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} |
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void Init() { |
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table_.clear(); |
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table_.resize(kInline); |
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table_.fill(kEmpty); |
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occupied_ = 0; |
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} |
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void Grow() { |
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Vec<int32_t> copy; |
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copy.MoveFrom(&table_); |
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occupied_ = 0; |
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table_.resize(copy.size() * 2); |
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table_.fill(kEmpty); |
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for (const auto& e : copy) { |
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if (e >= 0) insert(e); |
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} |
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} |
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NodeSet(const NodeSet&) = delete; |
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NodeSet& operator=(const NodeSet&) = delete; |
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}; |
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// We encode a node index and a node version in GraphId. The version |
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// number is incremented when the GraphId is freed which automatically |
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// invalidates all copies of the GraphId. |
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inline GraphId MakeId(int32_t index, uint32_t version) { |
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GraphId g; |
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g.handle = |
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(static_cast<uint64_t>(version) << 32) | static_cast<uint32_t>(index); |
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return g; |
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} |
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inline int32_t NodeIndex(GraphId id) { |
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return static_cast<int32_t>(id.handle); |
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} |
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inline uint32_t NodeVersion(GraphId id) { |
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return static_cast<uint32_t>(id.handle >> 32); |
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} |
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struct Node { |
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int32_t rank; // rank number assigned by Pearce-Kelly algorithm |
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uint32_t version; // Current version number |
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int32_t next_hash; // Next entry in hash table |
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bool visited; // Temporary marker used by depth-first-search |
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uintptr_t masked_ptr; // User-supplied pointer |
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NodeSet in; // List of immediate predecessor nodes in graph |
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NodeSet out; // List of immediate successor nodes in graph |
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int priority; // Priority of recorded stack trace. |
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int nstack; // Depth of recorded stack trace. |
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void* stack[40]; // stack[0,nstack-1] holds stack trace for node. |
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}; |
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// Hash table for pointer to node index lookups. |
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class PointerMap { |
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public: |
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explicit PointerMap(const Vec<Node*>* nodes) : nodes_(nodes) { |
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table_.fill(-1); |
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} |
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int32_t Find(void* ptr) { |
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auto masked = base_internal::HidePtr(ptr); |
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for (int32_t i = table_[Hash(ptr)]; i != -1;) { |
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Node* n = (*nodes_)[static_cast<uint32_t>(i)]; |
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if (n->masked_ptr == masked) return i; |
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i = n->next_hash; |
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} |
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return -1; |
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} |
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void Add(void* ptr, int32_t i) { |
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int32_t* head = &table_[Hash(ptr)]; |
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(*nodes_)[static_cast<uint32_t>(i)]->next_hash = *head; |
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*head = i; |
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} |
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int32_t Remove(void* ptr) { |
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// Advance through linked list while keeping track of the |
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// predecessor slot that points to the current entry. |
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auto masked = base_internal::HidePtr(ptr); |
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for (int32_t* slot = &table_[Hash(ptr)]; *slot != -1; ) { |
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int32_t index = *slot; |
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Node* n = (*nodes_)[static_cast<uint32_t>(index)]; |
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if (n->masked_ptr == masked) { |
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*slot = n->next_hash; // Remove n from linked list |
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n->next_hash = -1; |
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return index; |
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} |
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slot = &n->next_hash; |
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} |
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return -1; |
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} |
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private: |
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// Number of buckets in hash table for pointer lookups. |
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static constexpr uint32_t kHashTableSize = 8171; // should be prime |
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const Vec<Node*>* nodes_; |
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std::array<int32_t, kHashTableSize> table_; |
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static uint32_t Hash(void* ptr) { |
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return reinterpret_cast<uintptr_t>(ptr) % kHashTableSize; |
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} |
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}; |
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} // namespace |
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struct GraphCycles::Rep { |
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Vec<Node*> nodes_; |
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Vec<int32_t> free_nodes_; // Indices for unused entries in nodes_ |
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PointerMap ptrmap_; |
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// Temporary state. |
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Vec<int32_t> deltaf_; // Results of forward DFS |
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Vec<int32_t> deltab_; // Results of backward DFS |
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Vec<int32_t> list_; // All nodes to reprocess |
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Vec<int32_t> merged_; // Rank values to assign to list_ entries |
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Vec<int32_t> stack_; // Emulates recursion stack for depth-first searches |
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Rep() : ptrmap_(&nodes_) {} |
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}; |
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static Node* FindNode(GraphCycles::Rep* rep, GraphId id) { |
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Node* n = rep->nodes_[static_cast<uint32_t>(NodeIndex(id))]; |
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return (n->version == NodeVersion(id)) ? n : nullptr; |
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} |
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GraphCycles::GraphCycles() { |
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InitArenaIfNecessary(); |
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rep_ = new (base_internal::LowLevelAlloc::AllocWithArena(sizeof(Rep), arena)) |
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Rep; |
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} |
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GraphCycles::~GraphCycles() { |
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for (auto* node : rep_->nodes_) { |
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node->Node::~Node(); |
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base_internal::LowLevelAlloc::Free(node); |
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} |
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rep_->Rep::~Rep(); |
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base_internal::LowLevelAlloc::Free(rep_); |
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} |
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bool GraphCycles::CheckInvariants() const { |
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Rep* r = rep_; |
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NodeSet ranks; // Set of ranks seen so far. |
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for (uint32_t x = 0; x < r->nodes_.size(); x++) { |
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Node* nx = r->nodes_[x]; |
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void* ptr = base_internal::UnhidePtr<void>(nx->masked_ptr); |
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if (ptr != nullptr && static_cast<uint32_t>(r->ptrmap_.Find(ptr)) != x) { |
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ABSL_RAW_LOG(FATAL, "Did not find live node in hash table %u %p", x, ptr); |
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} |
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if (nx->visited) { |
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ABSL_RAW_LOG(FATAL, "Did not clear visited marker on node %u", x); |
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} |
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if (!ranks.insert(nx->rank)) { |
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ABSL_RAW_LOG(FATAL, "Duplicate occurrence of rank %d", nx->rank); |
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} |
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HASH_FOR_EACH(y, nx->out) { |
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Node* ny = r->nodes_[static_cast<uint32_t>(y)]; |
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if (nx->rank >= ny->rank) { |
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ABSL_RAW_LOG(FATAL, "Edge %u->%d has bad rank assignment %d->%d", x, y, |
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nx->rank, ny->rank); |
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} |
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} |
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} |
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return true; |
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} |
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GraphId GraphCycles::GetId(void* ptr) { |
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int32_t i = rep_->ptrmap_.Find(ptr); |
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if (i != -1) { |
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return MakeId(i, rep_->nodes_[static_cast<uint32_t>(i)]->version); |
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} else if (rep_->free_nodes_.empty()) { |
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Node* n = |
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new (base_internal::LowLevelAlloc::AllocWithArena(sizeof(Node), arena)) |
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Node; |
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n->version = 1; // Avoid 0 since it is used by InvalidGraphId() |
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n->visited = false; |
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n->rank = static_cast<int32_t>(rep_->nodes_.size()); |
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n->masked_ptr = base_internal::HidePtr(ptr); |
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n->nstack = 0; |
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n->priority = 0; |
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rep_->nodes_.push_back(n); |
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rep_->ptrmap_.Add(ptr, n->rank); |
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return MakeId(n->rank, n->version); |
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} else { |
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// Preserve preceding rank since the set of ranks in use must be |
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// a permutation of [0,rep_->nodes_.size()-1]. |
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int32_t r = rep_->free_nodes_.back(); |
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rep_->free_nodes_.pop_back(); |
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Node* n = rep_->nodes_[static_cast<uint32_t>(r)]; |
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n->masked_ptr = base_internal::HidePtr(ptr); |
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n->nstack = 0; |
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n->priority = 0; |
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rep_->ptrmap_.Add(ptr, r); |
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return MakeId(r, n->version); |
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} |
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} |
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void GraphCycles::RemoveNode(void* ptr) { |
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int32_t i = rep_->ptrmap_.Remove(ptr); |
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if (i == -1) { |
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return; |
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} |
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Node* x = rep_->nodes_[static_cast<uint32_t>(i)]; |
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HASH_FOR_EACH(y, x->out) { |
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rep_->nodes_[static_cast<uint32_t>(y)]->in.erase(i); |
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} |
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HASH_FOR_EACH(y, x->in) { |
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rep_->nodes_[static_cast<uint32_t>(y)]->out.erase(i); |
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} |
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x->in.clear(); |
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x->out.clear(); |
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x->masked_ptr = base_internal::HidePtr<void>(nullptr); |
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if (x->version == std::numeric_limits<uint32_t>::max()) { |
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// Cannot use x any more |
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} else { |
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x->version++; // Invalidates all copies of node. |
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rep_->free_nodes_.push_back(i); |
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} |
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} |
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void* GraphCycles::Ptr(GraphId id) { |
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Node* n = FindNode(rep_, id); |
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return n == nullptr ? nullptr |
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: base_internal::UnhidePtr<void>(n->masked_ptr); |
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} |
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bool GraphCycles::HasNode(GraphId node) { |
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return FindNode(rep_, node) != nullptr; |
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} |
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bool GraphCycles::HasEdge(GraphId x, GraphId y) const { |
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Node* xn = FindNode(rep_, x); |
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return xn && FindNode(rep_, y) && xn->out.contains(NodeIndex(y)); |
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} |
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void GraphCycles::RemoveEdge(GraphId x, GraphId y) { |
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Node* xn = FindNode(rep_, x); |
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Node* yn = FindNode(rep_, y); |
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if (xn && yn) { |
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xn->out.erase(NodeIndex(y)); |
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yn->in.erase(NodeIndex(x)); |
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// No need to update the rank assignment since a previous valid |
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// rank assignment remains valid after an edge deletion. |
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} |
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} |
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static bool ForwardDFS(GraphCycles::Rep* r, int32_t n, int32_t upper_bound); |
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static void BackwardDFS(GraphCycles::Rep* r, int32_t n, int32_t lower_bound); |
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static void Reorder(GraphCycles::Rep* r); |
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static void Sort(const Vec<Node*>&, Vec<int32_t>* delta); |
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static void MoveToList( |
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GraphCycles::Rep* r, Vec<int32_t>* src, Vec<int32_t>* dst); |
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bool GraphCycles::InsertEdge(GraphId idx, GraphId idy) { |
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Rep* r = rep_; |
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const int32_t x = NodeIndex(idx); |
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const int32_t y = NodeIndex(idy); |
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Node* nx = FindNode(r, idx); |
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Node* ny = FindNode(r, idy); |
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if (nx == nullptr || ny == nullptr) return true; // Expired ids |
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if (nx == ny) return false; // Self edge |
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if (!nx->out.insert(y)) { |
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// Edge already exists. |
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return true; |
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} |
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ny->in.insert(x); |
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if (nx->rank <= ny->rank) { |
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// New edge is consistent with existing rank assignment. |
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return true; |
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} |
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// Current rank assignments are incompatible with the new edge. Recompute. |
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// We only need to consider nodes that fall in the range [ny->rank,nx->rank]. |
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if (!ForwardDFS(r, y, nx->rank)) { |
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// Found a cycle. Undo the insertion and tell caller. |
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nx->out.erase(y); |
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ny->in.erase(x); |
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// Since we do not call Reorder() on this path, clear any visited |
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// markers left by ForwardDFS. |
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for (const auto& d : r->deltaf_) { |
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r->nodes_[static_cast<uint32_t>(d)]->visited = false; |
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} |
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return false; |
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} |
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BackwardDFS(r, x, ny->rank); |
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Reorder(r); |
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return true; |
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} |
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static bool ForwardDFS(GraphCycles::Rep* r, int32_t n, int32_t upper_bound) { |
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// Avoid recursion since stack space might be limited. |
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// We instead keep a stack of nodes to visit. |
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r->deltaf_.clear(); |
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r->stack_.clear(); |
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r->stack_.push_back(n); |
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while (!r->stack_.empty()) { |
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n = r->stack_.back(); |
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r->stack_.pop_back(); |
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Node* nn = r->nodes_[static_cast<uint32_t>(n)]; |
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if (nn->visited) continue; |
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nn->visited = true; |
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r->deltaf_.push_back(n); |
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HASH_FOR_EACH(w, nn->out) { |
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Node* nw = r->nodes_[static_cast<uint32_t>(w)]; |
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if (nw->rank == upper_bound) { |
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return false; // Cycle |
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} |
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if (!nw->visited && nw->rank < upper_bound) { |
|
r->stack_.push_back(w); |
|
} |
|
} |
|
} |
|
return true; |
|
} |
|
|
|
static void BackwardDFS(GraphCycles::Rep* r, int32_t n, int32_t lower_bound) { |
|
r->deltab_.clear(); |
|
r->stack_.clear(); |
|
r->stack_.push_back(n); |
|
while (!r->stack_.empty()) { |
|
n = r->stack_.back(); |
|
r->stack_.pop_back(); |
|
Node* nn = r->nodes_[static_cast<uint32_t>(n)]; |
|
if (nn->visited) continue; |
|
|
|
nn->visited = true; |
|
r->deltab_.push_back(n); |
|
|
|
HASH_FOR_EACH(w, nn->in) { |
|
Node* nw = r->nodes_[static_cast<uint32_t>(w)]; |
|
if (!nw->visited && lower_bound < nw->rank) { |
|
r->stack_.push_back(w); |
|
} |
|
} |
|
} |
|
} |
|
|
|
static void Reorder(GraphCycles::Rep* r) { |
|
Sort(r->nodes_, &r->deltab_); |
|
Sort(r->nodes_, &r->deltaf_); |
|
|
|
// Adds contents of delta lists to list_ (backwards deltas first). |
|
r->list_.clear(); |
|
MoveToList(r, &r->deltab_, &r->list_); |
|
MoveToList(r, &r->deltaf_, &r->list_); |
|
|
|
// Produce sorted list of all ranks that will be reassigned. |
|
r->merged_.resize(r->deltab_.size() + r->deltaf_.size()); |
|
std::merge(r->deltab_.begin(), r->deltab_.end(), |
|
r->deltaf_.begin(), r->deltaf_.end(), |
|
r->merged_.begin()); |
|
|
|
// Assign the ranks in order to the collected list. |
|
for (uint32_t i = 0; i < r->list_.size(); i++) { |
|
r->nodes_[static_cast<uint32_t>(r->list_[i])]->rank = r->merged_[i]; |
|
} |
|
} |
|
|
|
static void Sort(const Vec<Node*>& nodes, Vec<int32_t>* delta) { |
|
struct ByRank { |
|
const Vec<Node*>* nodes; |
|
bool operator()(int32_t a, int32_t b) const { |
|
return (*nodes)[static_cast<uint32_t>(a)]->rank < |
|
(*nodes)[static_cast<uint32_t>(b)]->rank; |
|
} |
|
}; |
|
ByRank cmp; |
|
cmp.nodes = &nodes; |
|
std::sort(delta->begin(), delta->end(), cmp); |
|
} |
|
|
|
static void MoveToList( |
|
GraphCycles::Rep* r, Vec<int32_t>* src, Vec<int32_t>* dst) { |
|
for (auto& v : *src) { |
|
int32_t w = v; |
|
// Replace v entry with its rank |
|
v = r->nodes_[static_cast<uint32_t>(w)]->rank; |
|
// Prepare for future DFS calls |
|
r->nodes_[static_cast<uint32_t>(w)]->visited = false; |
|
dst->push_back(w); |
|
} |
|
} |
|
|
|
int GraphCycles::FindPath(GraphId idx, GraphId idy, int max_path_len, |
|
GraphId path[]) const { |
|
Rep* r = rep_; |
|
if (FindNode(r, idx) == nullptr || FindNode(r, idy) == nullptr) return 0; |
|
const int32_t x = NodeIndex(idx); |
|
const int32_t y = NodeIndex(idy); |
|
|
|
// Forward depth first search starting at x until we hit y. |
|
// As we descend into a node, we push it onto the path. |
|
// As we leave a node, we remove it from the path. |
|
int path_len = 0; |
|
|
|
NodeSet seen; |
|
r->stack_.clear(); |
|
r->stack_.push_back(x); |
|
while (!r->stack_.empty()) { |
|
int32_t n = r->stack_.back(); |
|
r->stack_.pop_back(); |
|
if (n < 0) { |
|
// Marker to indicate that we are leaving a node |
|
path_len--; |
|
continue; |
|
} |
|
|
|
if (path_len < max_path_len) { |
|
path[path_len] = |
|
MakeId(n, rep_->nodes_[static_cast<uint32_t>(n)]->version); |
|
} |
|
path_len++; |
|
r->stack_.push_back(-1); // Will remove tentative path entry |
|
|
|
if (n == y) { |
|
return path_len; |
|
} |
|
|
|
HASH_FOR_EACH(w, r->nodes_[static_cast<uint32_t>(n)]->out) { |
|
if (seen.insert(w)) { |
|
r->stack_.push_back(w); |
|
} |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
bool GraphCycles::IsReachable(GraphId x, GraphId y) const { |
|
return FindPath(x, y, 0, nullptr) > 0; |
|
} |
|
|
|
void GraphCycles::UpdateStackTrace(GraphId id, int priority, |
|
int (*get_stack_trace)(void** stack, int)) { |
|
Node* n = FindNode(rep_, id); |
|
if (n == nullptr || n->priority >= priority) { |
|
return; |
|
} |
|
n->nstack = (*get_stack_trace)(n->stack, ABSL_ARRAYSIZE(n->stack)); |
|
n->priority = priority; |
|
} |
|
|
|
int GraphCycles::GetStackTrace(GraphId id, void*** ptr) { |
|
Node* n = FindNode(rep_, id); |
|
if (n == nullptr) { |
|
*ptr = nullptr; |
|
return 0; |
|
} else { |
|
*ptr = n->stack; |
|
return n->nstack; |
|
} |
|
} |
|
|
|
} // namespace synchronization_internal |
|
ABSL_NAMESPACE_END |
|
} // namespace absl |
|
|
|
#endif // ABSL_LOW_LEVEL_ALLOC_MISSING
|
|
|