libcxx/test/support/test_allocator.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef TEST_ALLOCATOR_H
  10 #define TEST_ALLOCATOR_H
  11
  12 #include <type_traits>
  13 #include <new>
  14 #include <memory>
  15 #include <utility>
  16 #include <cstddef>
  17 #include <cstdlib>
  18 #include <climits>
  19 #include <cassert>
  20
  21 #include "test_macros.h"
  22
  23 template <class Alloc>
  24 TEST_CONSTEXPR_CXX20 inline typename std::allocator_traits<Alloc>::size_type alloc_max_size(Alloc const& a) {
  25   typedef std::allocator_traits<Alloc> AT;
  26   return AT::max_size(a);
  27 }
  28
  29 struct test_allocator_statistics {
  30   int time_to_throw = 0;
  31   int throw_after = INT_MAX;
  32   int count           = 0; // the number of active instances
  33   int alloc_count     = 0; // the number of allocations not deallocating
  34   int allocated_size  = 0; // the size of allocated elements
  35   int construct_count = 0; // the number of times that ::construct was called
  36   int destroy_count = 0; // the number of times that ::destroy was called
  37   int copied = 0;
  38   int moved = 0;
  39   int converted = 0;
  40
  41   TEST_CONSTEXPR_CXX14 void clear() {
  42     assert(count == 0 && "clearing leaking allocator data?");
  43     count = 0;
  44     time_to_throw = 0;
  45     alloc_count = 0;
  46     allocated_size  = 0;
  47     construct_count = 0;
  48     destroy_count = 0;
  49     throw_after = INT_MAX;
  50     clear_ctor_counters();
  51   }
  52
  53   TEST_CONSTEXPR_CXX14 void clear_ctor_counters() {
  54     copied = 0;
  55     moved = 0;
  56     converted = 0;
  57   }
  58 };
  59
  60 struct test_alloc_base {
  61   TEST_CONSTEXPR static const int destructed_value = -1;
  62   TEST_CONSTEXPR static const int moved_value = INT_MAX;
  63 };
  64
  65 template <class T>
  66 class test_allocator {
  67   int data_ = 0; // participates in equality
  68   int id_ = 0;   // unique identifier, doesn't participate in equality
  69   test_allocator_statistics* stats_ = nullptr;
  70
  71   template <class U>
  72   friend class test_allocator;
  73
  74 public:
  75   typedef unsigned size_type;
  76   typedef int difference_type;
  77   typedef T value_type;
  78   typedef value_type* pointer;
  79   typedef const value_type* const_pointer;
  80   typedef typename std::add_lvalue_reference<value_type>::type reference;
  81   typedef typename std::add_lvalue_reference<const value_type>::type const_reference;
  82
  83   template <class U>
  84   struct rebind {
  85     typedef test_allocator<U> other;
  86   };
  87
  88   TEST_CONSTEXPR test_allocator() TEST_NOEXCEPT = default;
  89
  90   TEST_CONSTEXPR_CXX14 explicit test_allocator(test_allocator_statistics* stats) TEST_NOEXCEPT : stats_(stats) {
  91     if (stats_ != nullptr)
  92       ++stats_->count;
  93   }
  94
  95   TEST_CONSTEXPR explicit test_allocator(int data) TEST_NOEXCEPT : data_(data) {}
  96
  97   TEST_CONSTEXPR_CXX14 explicit test_allocator(int data, test_allocator_statistics* stats) TEST_NOEXCEPT
  98       : data_(data), stats_(stats) {
  99     if (stats != nullptr)
 100       ++stats_->count;
 101   }
 102
 103   TEST_CONSTEXPR explicit test_allocator(int data, int id) TEST_NOEXCEPT : data_(data), id_(id) {}
 104
 105   TEST_CONSTEXPR_CXX14 explicit test_allocator(int data, int id, test_allocator_statistics* stats) TEST_NOEXCEPT
 106       : data_(data), id_(id), stats_(stats) {
 107     if (stats_ != nullptr)
 108       ++stats_->count;
 109   }
 110
 111   TEST_CONSTEXPR_CXX14 test_allocator(const test_allocator& a) TEST_NOEXCEPT
 112     : data_(a.data_), id_(a.id_), stats_(a.stats_) {
 113     assert(a.data_ != test_alloc_base::destructed_value && a.id_ != test_alloc_base::destructed_value &&
 114            "copying from destroyed allocator");
 115     if (stats_ != nullptr) {
 116       ++stats_->count;
 117       ++stats_->copied;
 118     }
 119   }
 120
 121   TEST_CONSTEXPR_CXX14 test_allocator(test_allocator&& a) TEST_NOEXCEPT : data_(a.data_), id_(a.id_), stats_(a.stats_) {
 122     if (stats_ != nullptr) {
 123       ++stats_->count;
 124       ++stats_->moved;
 125     }
 126     assert(a.data_ != test_alloc_base::destructed_value && a.id_ != test_alloc_base::destructed_value &&
 127            "moving from destroyed allocator");
 128     a.id_ = test_alloc_base::moved_value;
 129   }
 130
 131   template <class U>
 132   TEST_CONSTEXPR_CXX14 test_allocator(const test_allocator<U>& a) TEST_NOEXCEPT
 133       : data_(a.data_), id_(a.id_), stats_(a.stats_) {
 134     if (stats_ != nullptr) {
 135       ++stats_->count;
 136       ++stats_->converted;
 137     }
 138   }
 139
 140   TEST_CONSTEXPR_CXX20 ~test_allocator() TEST_NOEXCEPT {
 141     assert(data_ != test_alloc_base::destructed_value);
 142     assert(id_ != test_alloc_base::destructed_value);
 143     if (stats_ != nullptr)
 144       --stats_->count;
 145     data_ = test_alloc_base::destructed_value;
 146     id_ = test_alloc_base::destructed_value;
 147   }
 148
 149   TEST_CONSTEXPR pointer address(reference x) const { return &x; }
 150   TEST_CONSTEXPR const_pointer address(const_reference x) const { return &x; }
 151
 152   TEST_CONSTEXPR_CXX14 pointer allocate(size_type n, const void* = nullptr) {
 153     assert(data_ != test_alloc_base::destructed_value);
 154     if (stats_ != nullptr) {
 155       if (stats_->time_to_throw >= stats_->throw_after)
 156         TEST_THROW(std::bad_alloc());
 157       ++stats_->time_to_throw;
 158       ++stats_->alloc_count;
 159       stats_->allocated_size += n;
 160     }
 161     return std::allocator<value_type>().allocate(n);
 162   }
 163
 164   TEST_CONSTEXPR_CXX14 void deallocate(pointer p, size_type s) {
 165     assert(data_ != test_alloc_base::destructed_value);
 166     if (stats_ != nullptr) {
 167       --stats_->alloc_count;
 168       stats_->allocated_size -= s;
 169     }
 170     std::allocator<value_type>().deallocate(p, s);
 171   }
 172
 173   TEST_CONSTEXPR size_type max_size() const TEST_NOEXCEPT { return UINT_MAX / sizeof(T); }
 174
 175   template <class U>
 176   TEST_CONSTEXPR_CXX20 void construct(pointer p, U&& val) {
 177     if (stats_ != nullptr)
 178       ++stats_->construct_count;
 179 #if TEST_STD_VER > 17
 180     std::construct_at(std::to_address(p), std::forward<U>(val));
 181 #else
 182     ::new (static_cast<void*>(p)) T(std::forward<U>(val));
 183 #endif
 184   }
 185
 186   TEST_CONSTEXPR_CXX14 void destroy(pointer p) {
 187     if (stats_ != nullptr)
 188       ++stats_->destroy_count;
 189     p->~T();
 190   }
 191   TEST_CONSTEXPR friend bool operator==(const test_allocator& x, const test_allocator& y) { return x.data_ == y.data_; }
 192   TEST_CONSTEXPR friend bool operator!=(const test_allocator& x, const test_allocator& y) { return !(x == y); }
 193
 194   TEST_CONSTEXPR int get_data() const { return data_; }
 195   TEST_CONSTEXPR int get_id() const { return id_; }
 196 };
 197
 198 template <>
 199 class test_allocator<void> {
 200   int data_ = 0;
 201   int id_ = 0;
 202   test_allocator_statistics* stats_ = nullptr;
 203
 204   template <class U>
 205   friend class test_allocator;
 206
 207 public:
 208   typedef unsigned size_type;
 209   typedef int difference_type;
 210   typedef void value_type;
 211   typedef value_type* pointer;
 212   typedef const value_type* const_pointer;
 213
 214   template <class U>
 215   struct rebind {
 216     typedef test_allocator<U> other;
 217   };
 218
 219   TEST_CONSTEXPR test_allocator() TEST_NOEXCEPT = default;
 220
 221   TEST_CONSTEXPR_CXX14 explicit test_allocator(test_allocator_statistics* stats) TEST_NOEXCEPT : stats_(stats) {}
 222
 223   TEST_CONSTEXPR explicit test_allocator(int data) TEST_NOEXCEPT : data_(data) {}
 224
 225   TEST_CONSTEXPR explicit test_allocator(int data, test_allocator_statistics* stats) TEST_NOEXCEPT
 226       : data_(data), stats_(stats)
 227   {}
 228
 229   TEST_CONSTEXPR explicit test_allocator(int data, int id) : data_(data), id_(id) {}
 230
 231   TEST_CONSTEXPR_CXX14 explicit test_allocator(int data, int id, test_allocator_statistics* stats) TEST_NOEXCEPT
 232       : data_(data), id_(id), stats_(stats)
 233   {}
 234
 235   TEST_CONSTEXPR_CXX14 explicit test_allocator(const test_allocator& a) TEST_NOEXCEPT
 236       : data_(a.data_), id_(a.id_), stats_(a.stats_)
 237   {}
 238
 239   template <class U>
 240   TEST_CONSTEXPR_CXX14 test_allocator(const test_allocator<U>& a) TEST_NOEXCEPT
 241       : data_(a.data_), id_(a.id_), stats_(a.stats_)
 242   {}
 243
 244   TEST_CONSTEXPR_CXX20 ~test_allocator() TEST_NOEXCEPT {
 245     data_ = test_alloc_base::destructed_value;
 246     id_ = test_alloc_base::destructed_value;
 247   }
 248
 249   TEST_CONSTEXPR int get_id() const { return id_; }
 250   TEST_CONSTEXPR int get_data() const { return data_; }
 251
 252   TEST_CONSTEXPR friend bool operator==(const test_allocator& x, const test_allocator& y) { return x.data_ == y.data_; }
 253   TEST_CONSTEXPR friend bool operator!=(const test_allocator& x, const test_allocator& y) { return !(x == y); }
 254 };
 255
 256 template <class T>
 257 class other_allocator {
 258   int data_ = -1;
 259
 260   template <class U>
 261   friend class other_allocator;
 262
 263 public:
 264   typedef T value_type;
 265
 266   TEST_CONSTEXPR_CXX14 other_allocator() {}
 267   TEST_CONSTEXPR_CXX14 explicit other_allocator(int i) : data_(i) {}
 268
 269   template <class U>
 270   TEST_CONSTEXPR_CXX14 other_allocator(const other_allocator<U>& a) : data_(a.data_) {}
 271
 272   TEST_CONSTEXPR_CXX20 T* allocate(std::size_t n) { return std::allocator<value_type>().allocate(n); }
 273   TEST_CONSTEXPR_CXX20 void deallocate(T* p, std::size_t s) { std::allocator<value_type>().deallocate(p, s); }
 274
 275   TEST_CONSTEXPR_CXX14 other_allocator select_on_container_copy_construction() const { return other_allocator(-2); }
 276
 277   TEST_CONSTEXPR_CXX14 friend bool operator==(const other_allocator& x, const other_allocator& y) {
 278     return x.data_ == y.data_;
 279   }
 280
 281   TEST_CONSTEXPR_CXX14 friend bool operator!=(const other_allocator& x, const other_allocator& y) { return !(x == y); }
 282   TEST_CONSTEXPR int get_data() const { return data_; }
 283
 284   typedef std::true_type propagate_on_container_copy_assignment;
 285   typedef std::true_type propagate_on_container_move_assignment;
 286   typedef std::true_type propagate_on_container_swap;
 287
 288 #if TEST_STD_VER < 11
 289   std::size_t max_size() const { return UINT_MAX / sizeof(T); }
 290 #endif
 291 };
 292
 293 struct Ctor_Tag {};
 294
 295 template <typename T>
 296 class TaggingAllocator;
 297
 298 struct Tag_X {
 299   // All constructors must be passed the Tag type.
 300
 301   // DefaultInsertable into vector<X, TaggingAllocator<X>>,
 302   TEST_CONSTEXPR Tag_X(Ctor_Tag) {}
 303   // CopyInsertable into vector<X, TaggingAllocator<X>>,
 304   TEST_CONSTEXPR Tag_X(Ctor_Tag, const Tag_X&) {}
 305   // MoveInsertable into vector<X, TaggingAllocator<X>>, and
 306   TEST_CONSTEXPR Tag_X(Ctor_Tag, Tag_X&&) {}
 307
 308   // EmplaceConstructible into vector<X, TaggingAllocator<X>> from args.
 309   template <typename... Args>
 310   TEST_CONSTEXPR Tag_X(Ctor_Tag, Args&&...) {}
 311
 312   // not DefaultConstructible, CopyConstructible or MoveConstructible.
 313   Tag_X() = delete;
 314   Tag_X(const Tag_X&) = delete;
 315   Tag_X(Tag_X&&) = delete;
 316
 317   // CopyAssignable.
 318   TEST_CONSTEXPR_CXX14 Tag_X& operator=(const Tag_X&) { return *this; };
 319
 320   // MoveAssignable.
 321   TEST_CONSTEXPR_CXX14 Tag_X& operator=(Tag_X&&) { return *this; };
 322
 323 private:
 324   ~Tag_X() = default;
 325   // Erasable from vector<X, TaggingAllocator<X>>.
 326   friend class TaggingAllocator<Tag_X>;
 327 };
 328
 329 template <typename T>
 330 class TaggingAllocator {
 331 public:
 332   using value_type = T;
 333   TaggingAllocator() = default;
 334
 335   template <typename U>
 336   TEST_CONSTEXPR TaggingAllocator(const TaggingAllocator<U>&) {}
 337
 338   template <typename... Args>
 339   TEST_CONSTEXPR_CXX20 void construct(Tag_X* p, Args&&... args) {
 340 #if TEST_STD_VER > 17
 341     std::construct_at(p, Ctor_Tag{}, std::forward<Args>(args)...);
 342 #else
 343     ::new (static_cast<void*>(p)) Tag_X(Ctor_Tag(), std::forward<Args>(args)...);
 344 #endif
 345   }
 346
 347   template <typename U>
 348   TEST_CONSTEXPR_CXX20 void destroy(U* p) {
 349     p->~U();
 350   }
 351
 352   TEST_CONSTEXPR_CXX20 T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
 353   TEST_CONSTEXPR_CXX20 void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n); }
 354 };
 355
 356 template <std::size_t MaxAllocs>
 357 struct limited_alloc_handle {
 358   std::size_t outstanding_ = 0;
 359   void* last_alloc_ = nullptr;
 360
 361   template <class T>
 362   TEST_CONSTEXPR_CXX20 T* allocate(std::size_t N) {
 363     if (N + outstanding_ > MaxAllocs)
 364       TEST_THROW(std::bad_alloc());
 365     auto alloc = std::allocator<T>().allocate(N);
 366     last_alloc_ = alloc;
 367     outstanding_ += N;
 368     return alloc;
 369   }
 370
 371   template <class T>
 372   TEST_CONSTEXPR_CXX20 void deallocate(T* ptr, std::size_t N) {
 373     if (ptr == last_alloc_) {
 374       last_alloc_ = nullptr;
 375       assert(outstanding_ >= N);
 376       outstanding_ -= N;
 377     }
 378     std::allocator<T>().deallocate(ptr, N);
 379   }
 380 };
 381
 382 namespace detail {
 383 template <class T>
 384 class thread_unsafe_shared_ptr {
 385 public:
 386   thread_unsafe_shared_ptr() = default;
 387
 388   TEST_CONSTEXPR_CXX14 thread_unsafe_shared_ptr(const thread_unsafe_shared_ptr& other) : block(other.block) {
 389     ++block->ref_count;
 390   }
 391
 392   TEST_CONSTEXPR_CXX20 ~thread_unsafe_shared_ptr() {
 393     --block->ref_count;
 394     if (block->ref_count != 0)
 395       return;
 396     typedef std::allocator_traits<std::allocator<control_block> > allocator_traits;
 397     std::allocator<control_block> alloc;
 398     allocator_traits::destroy(alloc, block);
 399     allocator_traits::deallocate(alloc, block, 1);
 400   }
 401
 402   TEST_CONSTEXPR const T& operator*() const { return block->content; }
 403   TEST_CONSTEXPR const T* operator->() const { return &block->content; }
 404   TEST_CONSTEXPR_CXX14 T& operator*() { return block->content; }
 405   TEST_CONSTEXPR_CXX14 T* operator->() { return &block->content; }
 406   TEST_CONSTEXPR_CXX14 T* get() { return &block->content; }
 407   TEST_CONSTEXPR const T* get() const { return &block->content; }
 408
 409 private:
 410   struct control_block {
 411     template <class... Args>
 412     TEST_CONSTEXPR control_block(Args... args) : content(std::forward<Args>(args)...) {}
 413     std::size_t ref_count = 1;
 414     T content;
 415   };
 416
 417   control_block* block = nullptr;
 418
 419   template <class U, class... Args>
 420   friend TEST_CONSTEXPR_CXX20 thread_unsafe_shared_ptr<U> make_thread_unsafe_shared(Args...);
 421 };
 422
 423 template <class T, class... Args>
 424 TEST_CONSTEXPR_CXX20 thread_unsafe_shared_ptr<T> make_thread_unsafe_shared(Args... args) {
 425   typedef typename thread_unsafe_shared_ptr<T>::control_block control_block_type;
 426   typedef std::allocator_traits<std::allocator<control_block_type> > allocator_traits;
 427
 428   thread_unsafe_shared_ptr<T> ptr;
 429   std::allocator<control_block_type> alloc;
 430   ptr.block = allocator_traits::allocate(alloc, 1);
 431   allocator_traits::construct(alloc, ptr.block, std::forward<Args>(args)...);
 432
 433   return ptr;
 434 }
 435 } // namespace detail
 436
 437 template <class T, std::size_t N>
 438 class limited_allocator {
 439   template <class U, std::size_t UN>
 440   friend class limited_allocator;
 441   typedef limited_alloc_handle<N> BuffT;
 442   detail::thread_unsafe_shared_ptr<BuffT> handle_;
 443
 444 public:
 445   typedef T value_type;
 446   typedef value_type* pointer;
 447   typedef const value_type* const_pointer;
 448   typedef value_type& reference;
 449   typedef const value_type& const_reference;
 450   typedef std::size_t size_type;
 451   typedef std::ptrdiff_t difference_type;
 452
 453   template <class U>
 454   struct rebind {
 455     typedef limited_allocator<U, N> other;
 456   };
 457
 458   TEST_CONSTEXPR_CXX20 limited_allocator() : handle_(detail::make_thread_unsafe_shared<BuffT>()) {}
 459
 460   limited_allocator(limited_allocator const&) = default;
 461
 462   template <class U>
 463   TEST_CONSTEXPR explicit limited_allocator(limited_allocator<U, N> const& other) : handle_(other.handle_) {}
 464
 465   limited_allocator& operator=(const limited_allocator&) = delete;
 466
 467   TEST_CONSTEXPR_CXX20 pointer allocate(size_type n) { return handle_->template allocate<T>(n); }
 468   TEST_CONSTEXPR_CXX20 void deallocate(pointer p, size_type n) { handle_->template deallocate<T>(p, n); }
 469   TEST_CONSTEXPR size_type max_size() const { return N; }
 470   TEST_CONSTEXPR BuffT* getHandle() const { return handle_.get(); }
 471 };
 472
 473 template <class T, class U, std::size_t N>
 474 TEST_CONSTEXPR inline bool operator==(limited_allocator<T, N> const& LHS, limited_allocator<U, N> const& RHS) {
 475   return LHS.getHandle() == RHS.getHandle();
 476 }
 477
 478 template <class T, class U, std::size_t N>
 479 TEST_CONSTEXPR inline bool operator!=(limited_allocator<T, N> const& LHS, limited_allocator<U, N> const& RHS) {
 480   return !(LHS == RHS);
 481 }
 482
 483 // Track the "provenance" of this allocator instance: how many times was
 484 // select_on_container_copy_construction called in order to produce it?
 485 //
 486 template <class T>
 487 struct SocccAllocator {
 488   using value_type = T;
 489
 490   int count_ = 0;
 491   explicit SocccAllocator(int i) : count_(i) {}
 492
 493   template <class U>
 494   SocccAllocator(const SocccAllocator<U>& a) : count_(a.count_) {}
 495
 496   T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
 497   void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n); }
 498
 499   SocccAllocator select_on_container_copy_construction() const { return SocccAllocator(count_ + 1); }
 500
 501   bool operator==(const SocccAllocator&) const { return true; }
 502
 503   using propagate_on_container_copy_assignment = std::false_type;
 504   using propagate_on_container_move_assignment = std::false_type;
 505   using propagate_on_container_swap            = std::false_type;
 506 };
 507
 508 #endif // TEST_ALLOCATOR_H