DenseMap.h revision 7f6c82a7e0fbf8ed012bc76471576c8cc42370a3
1//===- llvm/ADT/DenseMap.h - Dense probed hash table ------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines the DenseMap class. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_ADT_DENSEMAP_H 15#define LLVM_ADT_DENSEMAP_H 16 17#include "llvm/Support/Compiler.h" 18#include "llvm/Support/MathExtras.h" 19#include "llvm/Support/PointerLikeTypeTraits.h" 20#include "llvm/Support/type_traits.h" 21#include "llvm/ADT/DenseMapInfo.h" 22#include <algorithm> 23#include <iterator> 24#include <new> 25#include <utility> 26#include <cassert> 27#include <cstddef> 28#include <cstring> 29 30namespace llvm { 31 32template<typename KeyT, typename ValueT, 33 typename KeyInfoT = DenseMapInfo<KeyT>, 34 bool IsConst = false> 35class DenseMapIterator; 36 37template<typename DerivedT, 38 typename KeyT, typename ValueT, typename KeyInfoT> 39class DenseMapBase { 40protected: 41 typedef std::pair<KeyT, ValueT> BucketT; 42 unsigned NumEntries; 43 unsigned NumTombstones; 44 45public: 46 typedef KeyT key_type; 47 typedef ValueT mapped_type; 48 typedef BucketT value_type; 49 50 typedef DenseMapIterator<KeyT, ValueT, KeyInfoT> iterator; 51 typedef DenseMapIterator<KeyT, ValueT, 52 KeyInfoT, true> const_iterator; 53 inline iterator begin() { 54 // When the map is empty, avoid the overhead of AdvancePastEmptyBuckets(). 55 return empty() ? end() : iterator(getBuckets(), getBucketsEnd()); 56 } 57 inline iterator end() { 58 return iterator(getBucketsEnd(), getBucketsEnd(), true); 59 } 60 inline const_iterator begin() const { 61 return empty() ? end() : const_iterator(getBuckets(), getBucketsEnd()); 62 } 63 inline const_iterator end() const { 64 return const_iterator(getBucketsEnd(), getBucketsEnd(), true); 65 } 66 67 bool empty() const { return NumEntries == 0; } 68 unsigned size() const { return NumEntries; } 69 70 /// Grow the densemap so that it has at least Size buckets. Does not shrink 71 void resize(size_t Size) { 72 if (Size > getNumBuckets()) 73 grow(Size); 74 } 75 76 void clear() { 77 if (NumEntries == 0 && NumTombstones == 0) return; 78 79 // If the capacity of the array is huge, and the # elements used is small, 80 // shrink the array. 81 if (NumEntries * 4 < getNumBuckets() && getNumBuckets() > 64) { 82 shrink_and_clear(); 83 return; 84 } 85 86 const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey(); 87 for (BucketT *P = getBuckets(), *E = getBucketsEnd(); P != E; ++P) { 88 if (!KeyInfoT::isEqual(P->first, EmptyKey)) { 89 if (!KeyInfoT::isEqual(P->first, TombstoneKey)) { 90 P->second.~ValueT(); 91 --NumEntries; 92 } 93 P->first = EmptyKey; 94 } 95 } 96 assert(NumEntries == 0 && "Node count imbalance!"); 97 NumTombstones = 0; 98 } 99 100 /// count - Return true if the specified key is in the map. 101 bool count(const KeyT &Val) const { 102 BucketT *TheBucket; 103 return LookupBucketFor(Val, TheBucket); 104 } 105 106 iterator find(const KeyT &Val) { 107 BucketT *TheBucket; 108 if (LookupBucketFor(Val, TheBucket)) 109 return iterator(TheBucket, getBucketsEnd(), true); 110 return end(); 111 } 112 const_iterator find(const KeyT &Val) const { 113 BucketT *TheBucket; 114 if (LookupBucketFor(Val, TheBucket)) 115 return const_iterator(TheBucket, getBucketsEnd(), true); 116 return end(); 117 } 118 119 /// Alternate version of find() which allows a different, and possibly 120 /// less expensive, key type. 121 /// The DenseMapInfo is responsible for supplying methods 122 /// getHashValue(LookupKeyT) and isEqual(LookupKeyT, KeyT) for each key 123 /// type used. 124 template<class LookupKeyT> 125 iterator find_as(const LookupKeyT &Val) { 126 BucketT *TheBucket; 127 if (LookupBucketFor(Val, TheBucket)) 128 return iterator(TheBucket, getBucketsEnd(), true); 129 return end(); 130 } 131 template<class LookupKeyT> 132 const_iterator find_as(const LookupKeyT &Val) const { 133 BucketT *TheBucket; 134 if (LookupBucketFor(Val, TheBucket)) 135 return const_iterator(TheBucket, getBucketsEnd(), true); 136 return end(); 137 } 138 139 /// lookup - Return the entry for the specified key, or a default 140 /// constructed value if no such entry exists. 141 ValueT lookup(const KeyT &Val) const { 142 BucketT *TheBucket; 143 if (LookupBucketFor(Val, TheBucket)) 144 return TheBucket->second; 145 return ValueT(); 146 } 147 148 // Inserts key,value pair into the map if the key isn't already in the map. 149 // If the key is already in the map, it returns false and doesn't update the 150 // value. 151 std::pair<iterator, bool> insert(const std::pair<KeyT, ValueT> &KV) { 152 BucketT *TheBucket; 153 if (LookupBucketFor(KV.first, TheBucket)) 154 return std::make_pair(iterator(TheBucket, getBucketsEnd(), true), 155 false); // Already in map. 156 157 // Otherwise, insert the new element. 158 TheBucket = InsertIntoBucket(KV.first, KV.second, TheBucket); 159 return std::make_pair(iterator(TheBucket, getBucketsEnd(), true), true); 160 } 161 162 /// insert - Range insertion of pairs. 163 template<typename InputIt> 164 void insert(InputIt I, InputIt E) { 165 for (; I != E; ++I) 166 insert(*I); 167 } 168 169 170 bool erase(const KeyT &Val) { 171 BucketT *TheBucket; 172 if (!LookupBucketFor(Val, TheBucket)) 173 return false; // not in map. 174 175 TheBucket->second.~ValueT(); 176 TheBucket->first = getTombstoneKey(); 177 --NumEntries; 178 ++NumTombstones; 179 return true; 180 } 181 void erase(iterator I) { 182 BucketT *TheBucket = &*I; 183 TheBucket->second.~ValueT(); 184 TheBucket->first = getTombstoneKey(); 185 --NumEntries; 186 ++NumTombstones; 187 } 188 189 value_type& FindAndConstruct(const KeyT &Key) { 190 BucketT *TheBucket; 191 if (LookupBucketFor(Key, TheBucket)) 192 return *TheBucket; 193 194 return *InsertIntoBucket(Key, ValueT(), TheBucket); 195 } 196 197 ValueT &operator[](const KeyT &Key) { 198 return FindAndConstruct(Key).second; 199 } 200 201#if LLVM_USE_RVALUE_REFERENCES 202 value_type& FindAndConstruct(KeyT &&Key) { 203 BucketT *TheBucket; 204 if (LookupBucketFor(Key, TheBucket)) 205 return *TheBucket; 206 207 return *InsertIntoBucket(Key, ValueT(), TheBucket); 208 } 209 210 ValueT &operator[](KeyT &&Key) { 211 return FindAndConstruct(Key).second; 212 } 213#endif 214 215 /// isPointerIntoBucketsArray - Return true if the specified pointer points 216 /// somewhere into the DenseMap's array of buckets (i.e. either to a key or 217 /// value in the DenseMap). 218 bool isPointerIntoBucketsArray(const void *Ptr) const { 219 return Ptr >= getBuckets() && Ptr < getBucketsEnd(); 220 } 221 222 /// getPointerIntoBucketsArray() - Return an opaque pointer into the buckets 223 /// array. In conjunction with the previous method, this can be used to 224 /// determine whether an insertion caused the DenseMap to reallocate. 225 const void *getPointerIntoBucketsArray() const { return getBuckets(); } 226 227protected: 228 DenseMapBase() : NumEntries(), NumTombstones() {} 229 230 void destroyAll() { 231 if (getNumBuckets() == 0) // Nothing to do. 232 return; 233 234 const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey(); 235 for (BucketT *P = getBuckets(), *E = getBucketsEnd(); P != E; ++P) { 236 if (!KeyInfoT::isEqual(P->first, EmptyKey) && 237 !KeyInfoT::isEqual(P->first, TombstoneKey)) 238 P->second.~ValueT(); 239 P->first.~KeyT(); 240 } 241 242#ifndef NDEBUG 243 memset((void*)getBuckets(), 0x5a, sizeof(BucketT)*getNumBuckets()); 244#endif 245 } 246 247 void initEmpty() { 248 NumEntries = 0; 249 NumTombstones = 0; 250 251 assert((getNumBuckets() & (getNumBuckets()-1)) == 0 && 252 "# initial buckets must be a power of two!"); 253 const KeyT EmptyKey = getEmptyKey(); 254 for (BucketT *B = getBuckets(), *E = getBucketsEnd(); B != E; ++B) 255 new (&B->first) KeyT(EmptyKey); 256 } 257 258 void moveFromOldBuckets(BucketT *OldBucketsBegin, BucketT *OldBucketsEnd) { 259 initEmpty(); 260 261 // Insert all the old elements. 262 const KeyT EmptyKey = getEmptyKey(); 263 const KeyT TombstoneKey = getTombstoneKey(); 264 for (BucketT *B = OldBucketsBegin, *E = OldBucketsEnd; B != E; ++B) { 265 if (!KeyInfoT::isEqual(B->first, EmptyKey) && 266 !KeyInfoT::isEqual(B->first, TombstoneKey)) { 267 // Insert the key/value into the new table. 268 BucketT *DestBucket; 269 bool FoundVal = LookupBucketFor(B->first, DestBucket); 270 (void)FoundVal; // silence warning. 271 assert(!FoundVal && "Key already in new map?"); 272 DestBucket->first = llvm_move(B->first); 273 new (&DestBucket->second) ValueT(llvm_move(B->second)); 274 ++NumEntries; 275 276 // Free the value. 277 B->second.~ValueT(); 278 } 279 B->first.~KeyT(); 280 } 281 282#ifndef NDEBUG 283 if (OldBucketsBegin != OldBucketsEnd) 284 memset((void*)OldBucketsBegin, 0x5a, 285 sizeof(BucketT) * (OldBucketsEnd - OldBucketsBegin)); 286#endif 287 } 288 289 template <typename OtherBaseT> 290 void copyFrom(const DenseMapBase<OtherBaseT, KeyT, ValueT, KeyInfoT>& other) { 291 assert(getNumBuckets() == other.getNumBuckets()); 292 293 NumEntries = other.NumEntries; 294 NumTombstones = other.NumTombstones; 295 296 if (isPodLike<KeyT>::value && isPodLike<ValueT>::value) 297 memcpy(getBuckets(), other.getBuckets(), 298 getNumBuckets() * sizeof(BucketT)); 299 else 300 for (size_t i = 0; i < getNumBuckets(); ++i) { 301 new (&getBuckets()[i].first) KeyT(other.getBuckets()[i].first); 302 if (!KeyInfoT::isEqual(getBuckets()[i].first, getEmptyKey()) && 303 !KeyInfoT::isEqual(getBuckets()[i].first, getTombstoneKey())) 304 new (&getBuckets()[i].second) ValueT(other.getBuckets()[i].second); 305 } 306 } 307 308 void swap(DenseMapBase& RHS) { 309 std::swap(NumEntries, RHS.NumEntries); 310 std::swap(NumTombstones, RHS.NumTombstones); 311 } 312 313private: 314 static unsigned getHashValue(const KeyT &Val) { 315 return KeyInfoT::getHashValue(Val); 316 } 317 template<typename LookupKeyT> 318 static unsigned getHashValue(const LookupKeyT &Val) { 319 return KeyInfoT::getHashValue(Val); 320 } 321 static const KeyT getEmptyKey() { 322 return KeyInfoT::getEmptyKey(); 323 } 324 static const KeyT getTombstoneKey() { 325 return KeyInfoT::getTombstoneKey(); 326 } 327 328 BucketT *getBuckets() const { 329 return static_cast<const DerivedT *>(this)->getBuckets(); 330 } 331 332 unsigned getNumBuckets() const { 333 return static_cast<const DerivedT *>(this)->getNumBuckets(); 334 } 335 336 BucketT *getBucketsEnd() const { 337 return getBuckets() + getNumBuckets(); 338 } 339 340 void grow(unsigned AtLeast) { 341 static_cast<DerivedT *>(this)->grow(AtLeast); 342 } 343 344 void shrink_and_clear() { 345 static_cast<DerivedT *>(this)->shrink_and_clear(); 346 NumTombstones = 0; 347 NumEntries = 0; 348 } 349 350 351 BucketT *InsertIntoBucket(const KeyT &Key, const ValueT &Value, 352 BucketT *TheBucket) { 353 TheBucket = InsertIntoBucketImpl(Key, TheBucket); 354 355 TheBucket->first = Key; 356 new (&TheBucket->second) ValueT(Value); 357 return TheBucket; 358 } 359 360#if LLVM_USE_RVALUE_REFERENCES 361 BucketT *InsertIntoBucket(const KeyT &Key, ValueT &&Value, 362 BucketT *TheBucket) { 363 TheBucket = InsertIntoBucketImpl(Key, TheBucket); 364 365 TheBucket->first = Key; 366 new (&TheBucket->second) ValueT(std::move(Value)); 367 return TheBucket; 368 } 369 370 BucketT *InsertIntoBucket(KeyT &&Key, ValueT &&Value, BucketT *TheBucket) { 371 TheBucket = InsertIntoBucketImpl(Key, TheBucket); 372 373 TheBucket->first = std::move(Key); 374 new (&TheBucket->second) ValueT(std::move(Value)); 375 return TheBucket; 376 } 377#endif 378 379 BucketT *InsertIntoBucketImpl(const KeyT &Key, BucketT *TheBucket) { 380 // If the load of the hash table is more than 3/4, or if fewer than 1/8 of 381 // the buckets are empty (meaning that many are filled with tombstones), 382 // grow the table. 383 // 384 // The later case is tricky. For example, if we had one empty bucket with 385 // tons of tombstones, failing lookups (e.g. for insertion) would have to 386 // probe almost the entire table until it found the empty bucket. If the 387 // table completely filled with tombstones, no lookup would ever succeed, 388 // causing infinite loops in lookup. 389 unsigned NewNumEntries = NumEntries + 1; 390 if (NewNumEntries*4 >= getNumBuckets()*3) { 391 this->grow(getNumBuckets() * 2); 392 LookupBucketFor(Key, TheBucket); 393 } 394 if (getNumBuckets()-(NewNumEntries+NumTombstones) < getNumBuckets()/8) { 395 this->grow(getNumBuckets()); 396 LookupBucketFor(Key, TheBucket); 397 } 398 399 // Only update the state after we've grown our bucket space appropriately 400 // so that when growing buckets we have self-consistent entry count. 401 ++NumEntries; 402 403 // If we are writing over a tombstone, remember this. 404 if (!KeyInfoT::isEqual(TheBucket->first, getEmptyKey())) 405 --NumTombstones; 406 407 return TheBucket; 408 } 409 410 /// LookupBucketFor - Lookup the appropriate bucket for Val, returning it in 411 /// FoundBucket. If the bucket contains the key and a value, this returns 412 /// true, otherwise it returns a bucket with an empty marker or tombstone and 413 /// returns false. 414 template<typename LookupKeyT> 415 bool LookupBucketFor(const LookupKeyT &Val, BucketT *&FoundBucket) const { 416 unsigned BucketNo = getHashValue(Val); 417 unsigned ProbeAmt = 1; 418 BucketT *BucketsPtr = getBuckets(); 419 420 if (getNumBuckets() == 0) { 421 FoundBucket = 0; 422 return false; 423 } 424 425 // FoundTombstone - Keep track of whether we find a tombstone while probing. 426 BucketT *FoundTombstone = 0; 427 const KeyT EmptyKey = getEmptyKey(); 428 const KeyT TombstoneKey = getTombstoneKey(); 429 assert(!KeyInfoT::isEqual(Val, EmptyKey) && 430 !KeyInfoT::isEqual(Val, TombstoneKey) && 431 "Empty/Tombstone value shouldn't be inserted into map!"); 432 433 while (1) { 434 BucketT *ThisBucket = BucketsPtr + (BucketNo & (getNumBuckets()-1)); 435 // Found Val's bucket? If so, return it. 436 if (KeyInfoT::isEqual(Val, ThisBucket->first)) { 437 FoundBucket = ThisBucket; 438 return true; 439 } 440 441 // If we found an empty bucket, the key doesn't exist in the set. 442 // Insert it and return the default value. 443 if (KeyInfoT::isEqual(ThisBucket->first, EmptyKey)) { 444 // If we've already seen a tombstone while probing, fill it in instead 445 // of the empty bucket we eventually probed to. 446 if (FoundTombstone) ThisBucket = FoundTombstone; 447 FoundBucket = FoundTombstone ? FoundTombstone : ThisBucket; 448 return false; 449 } 450 451 // If this is a tombstone, remember it. If Val ends up not in the map, we 452 // prefer to return it than something that would require more probing. 453 if (KeyInfoT::isEqual(ThisBucket->first, TombstoneKey) && !FoundTombstone) 454 FoundTombstone = ThisBucket; // Remember the first tombstone found. 455 456 // Otherwise, it's a hash collision or a tombstone, continue quadratic 457 // probing. 458 BucketNo += ProbeAmt++; 459 } 460 } 461 462public: 463 /// Return the approximate size (in bytes) of the actual map. 464 /// This is just the raw memory used by DenseMap. 465 /// If entries are pointers to objects, the size of the referenced objects 466 /// are not included. 467 size_t getMemorySize() const { 468 return getNumBuckets() * sizeof(BucketT); 469 } 470}; 471 472template<typename KeyT, typename ValueT, 473 typename KeyInfoT = DenseMapInfo<KeyT> > 474class DenseMap 475 : public DenseMapBase<DenseMap<KeyT, ValueT, KeyInfoT>, 476 KeyT, ValueT, KeyInfoT> { 477 // Lift some types from the dependent base class into this class for 478 // simplicity of referring to them. 479 typedef DenseMapBase<DenseMap, KeyT, ValueT, KeyInfoT> BaseT; 480 typedef typename BaseT::BucketT BucketT; 481 friend class DenseMapBase<DenseMap, KeyT, ValueT, KeyInfoT>; 482 483 BucketT *Buckets; 484 unsigned NumBuckets; 485 486public: 487 explicit DenseMap(unsigned NumInitBuckets = 0) { 488 init(NumInitBuckets); 489 } 490 491 DenseMap(const DenseMap &other) { 492 init(0); 493 copyFrom(other); 494 } 495 496#if LLVM_USE_RVALUE_REFERENCES 497 DenseMap(DenseMap &&other) { 498 init(0); 499 swap(other); 500 } 501#endif 502 503 template<typename InputIt> 504 DenseMap(const InputIt &I, const InputIt &E) { 505 init(NextPowerOf2(std::distance(I, E))); 506 this->insert(I, E); 507 } 508 509 ~DenseMap() { 510 this->destroyAll(); 511 operator delete(Buckets); 512 } 513 514 void swap(DenseMap& RHS) { 515 std::swap(NumBuckets, RHS.NumBuckets); 516 std::swap(Buckets, RHS.Buckets); 517 518 this->BaseT::swap(RHS); 519 } 520 521 DenseMap& operator=(const DenseMap& other) { 522 copyFrom(other); 523 return *this; 524 } 525 526#if LLVM_USE_RVALUE_REFERENCES 527 DenseMap& operator=(DenseMap &&other) { 528 this->destroyAll(); 529 operator delete(Buckets); 530 init(0); 531 swap(other); 532 return *this; 533 } 534#endif 535 536 void copyFrom(const DenseMap& other) { 537 this->destroyAll(); 538 operator delete(Buckets); 539 540 if (allocateBuckets(other.NumBuckets)) 541 this->BaseT::copyFrom(other); 542 } 543 544 void init(unsigned InitBuckets) { 545 if (allocateBuckets(InitBuckets)) 546 this->BaseT::initEmpty(); 547 } 548 549 void grow(unsigned AtLeast) { 550 unsigned OldNumBuckets = NumBuckets; 551 BucketT *OldBuckets = Buckets; 552 553 allocateBuckets(std::max<unsigned>(64, NextPowerOf2(AtLeast))); 554 assert(Buckets); 555 if (!OldBuckets) { 556 this->BaseT::initEmpty(); 557 return; 558 } 559 560 this->moveFromOldBuckets(OldBuckets, OldBuckets+OldNumBuckets); 561 562 // Free the old table. 563 operator delete(OldBuckets); 564 } 565 566 void shrink_and_clear() { 567 unsigned OldSize = this->size(); 568 this->destroyAll(); 569 570 // Reduce the number of buckets. 571 unsigned NewNumBuckets 572 = std::max(64, 1 << (Log2_32_Ceil(OldSize) + 1)); 573 if (NewNumBuckets == NumBuckets) { 574 this->BaseT::initEmpty(); 575 return; 576 } 577 578 operator delete(Buckets); 579 init(NewNumBuckets); 580 } 581 582private: 583 BucketT *getBuckets() const { 584 return Buckets; 585 } 586 587 unsigned getNumBuckets() const { 588 return NumBuckets; 589 } 590 591 bool allocateBuckets(unsigned Num) { 592 NumBuckets = Num; 593 if (NumBuckets == 0) { 594 Buckets = 0; 595 return false; 596 } 597 598 Buckets = static_cast<BucketT*>(operator new(sizeof(BucketT) * NumBuckets)); 599 return true; 600 } 601}; 602 603template<typename KeyT, typename ValueT, 604 typename KeyInfoT, bool IsConst> 605class DenseMapIterator { 606 typedef std::pair<KeyT, ValueT> Bucket; 607 typedef DenseMapIterator<KeyT, ValueT, 608 KeyInfoT, true> ConstIterator; 609 friend class DenseMapIterator<KeyT, ValueT, KeyInfoT, true>; 610public: 611 typedef ptrdiff_t difference_type; 612 typedef typename conditional<IsConst, const Bucket, Bucket>::type value_type; 613 typedef value_type *pointer; 614 typedef value_type &reference; 615 typedef std::forward_iterator_tag iterator_category; 616private: 617 pointer Ptr, End; 618public: 619 DenseMapIterator() : Ptr(0), End(0) {} 620 621 DenseMapIterator(pointer Pos, pointer E, bool NoAdvance = false) 622 : Ptr(Pos), End(E) { 623 if (!NoAdvance) AdvancePastEmptyBuckets(); 624 } 625 626 // If IsConst is true this is a converting constructor from iterator to 627 // const_iterator and the default copy constructor is used. 628 // Otherwise this is a copy constructor for iterator. 629 DenseMapIterator(const DenseMapIterator<KeyT, ValueT, 630 KeyInfoT, false>& I) 631 : Ptr(I.Ptr), End(I.End) {} 632 633 reference operator*() const { 634 return *Ptr; 635 } 636 pointer operator->() const { 637 return Ptr; 638 } 639 640 bool operator==(const ConstIterator &RHS) const { 641 return Ptr == RHS.operator->(); 642 } 643 bool operator!=(const ConstIterator &RHS) const { 644 return Ptr != RHS.operator->(); 645 } 646 647 inline DenseMapIterator& operator++() { // Preincrement 648 ++Ptr; 649 AdvancePastEmptyBuckets(); 650 return *this; 651 } 652 DenseMapIterator operator++(int) { // Postincrement 653 DenseMapIterator tmp = *this; ++*this; return tmp; 654 } 655 656private: 657 void AdvancePastEmptyBuckets() { 658 const KeyT Empty = KeyInfoT::getEmptyKey(); 659 const KeyT Tombstone = KeyInfoT::getTombstoneKey(); 660 661 while (Ptr != End && 662 (KeyInfoT::isEqual(Ptr->first, Empty) || 663 KeyInfoT::isEqual(Ptr->first, Tombstone))) 664 ++Ptr; 665 } 666}; 667 668template<typename KeyT, typename ValueT, typename KeyInfoT> 669static inline size_t 670capacity_in_bytes(const DenseMap<KeyT, ValueT, KeyInfoT> &X) { 671 return X.getMemorySize(); 672} 673 674} // end namespace llvm 675 676#endif 677