LLVM 18.0.0git
OnDiskHashTable.h
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1//===--- OnDiskHashTable.h - On-Disk Hash Table Implementation --*- C++ -*-===//
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/// \file
10/// Defines facilities for reading and writing on-disk hash tables.
11///
12//===----------------------------------------------------------------------===//
13#ifndef LLVM_SUPPORT_ONDISKHASHTABLE_H
14#define LLVM_SUPPORT_ONDISKHASHTABLE_H
15
22#include <cassert>
23#include <cstdlib>
24
25namespace llvm {
26
27/// Generates an on disk hash table.
28///
29/// This needs an \c Info that handles storing values into the hash table's
30/// payload and computes the hash for a given key. This should provide the
31/// following interface:
32///
33/// \code
34/// class ExampleInfo {
35/// public:
36/// typedef ExampleKey key_type; // Must be copy constructible
37/// typedef ExampleKey &key_type_ref;
38/// typedef ExampleData data_type; // Must be copy constructible
39/// typedef ExampleData &data_type_ref;
40/// typedef uint32_t hash_value_type; // The type the hash function returns.
41/// typedef uint32_t offset_type; // The type for offsets into the table.
42///
43/// /// Calculate the hash for Key
44/// static hash_value_type ComputeHash(key_type_ref Key);
45/// /// Return the lengths, in bytes, of the given Key/Data pair.
46/// static std::pair<offset_type, offset_type>
47/// EmitKeyDataLength(raw_ostream &Out, key_type_ref Key, data_type_ref Data);
48/// /// Write Key to Out. KeyLen is the length from EmitKeyDataLength.
49/// static void EmitKey(raw_ostream &Out, key_type_ref Key,
50/// offset_type KeyLen);
51/// /// Write Data to Out. DataLen is the length from EmitKeyDataLength.
52/// static void EmitData(raw_ostream &Out, key_type_ref Key,
53/// data_type_ref Data, offset_type DataLen);
54/// /// Determine if two keys are equal. Optional, only needed by contains.
55/// static bool EqualKey(key_type_ref Key1, key_type_ref Key2);
56/// };
57/// \endcode
58template <typename Info> class OnDiskChainedHashTableGenerator {
59 /// A single item in the hash table.
60 class Item {
61 public:
62 typename Info::key_type Key;
63 typename Info::data_type Data;
64 Item *Next;
65 const typename Info::hash_value_type Hash;
66
67 Item(typename Info::key_type_ref Key, typename Info::data_type_ref Data,
68 Info &InfoObj)
69 : Key(Key), Data(Data), Next(nullptr), Hash(InfoObj.ComputeHash(Key)) {}
70 };
71
72 typedef typename Info::offset_type offset_type;
73 offset_type NumBuckets;
74 offset_type NumEntries;
76
77 /// A linked list of values in a particular hash bucket.
78 struct Bucket {
79 offset_type Off;
80 unsigned Length;
81 Item *Head;
82 };
83
84 Bucket *Buckets;
85
86private:
87 /// Insert an item into the appropriate hash bucket.
88 void insert(Bucket *Buckets, size_t Size, Item *E) {
89 Bucket &B = Buckets[E->Hash & (Size - 1)];
90 E->Next = B.Head;
91 ++B.Length;
92 B.Head = E;
93 }
94
95 /// Resize the hash table, moving the old entries into the new buckets.
96 void resize(size_t NewSize) {
97 Bucket *NewBuckets = static_cast<Bucket *>(
98 safe_calloc(NewSize, sizeof(Bucket)));
99 // Populate NewBuckets with the old entries.
100 for (size_t I = 0; I < NumBuckets; ++I)
101 for (Item *E = Buckets[I].Head; E;) {
102 Item *N = E->Next;
103 E->Next = nullptr;
104 insert(NewBuckets, NewSize, E);
105 E = N;
106 }
107
108 free(Buckets);
109 NumBuckets = NewSize;
110 Buckets = NewBuckets;
111 }
112
113public:
114 /// Insert an entry into the table.
115 void insert(typename Info::key_type_ref Key,
116 typename Info::data_type_ref Data) {
117 Info InfoObj;
118 insert(Key, Data, InfoObj);
119 }
120
121 /// Insert an entry into the table.
122 ///
123 /// Uses the provided Info instead of a stack allocated one.
124 void insert(typename Info::key_type_ref Key,
125 typename Info::data_type_ref Data, Info &InfoObj) {
126 ++NumEntries;
127 if (4 * NumEntries >= 3 * NumBuckets)
128 resize(NumBuckets * 2);
129 insert(Buckets, NumBuckets, new (BA.Allocate()) Item(Key, Data, InfoObj));
130 }
131
132 /// Determine whether an entry has been inserted.
133 bool contains(typename Info::key_type_ref Key, Info &InfoObj) {
134 unsigned Hash = InfoObj.ComputeHash(Key);
135 for (Item *I = Buckets[Hash & (NumBuckets - 1)].Head; I; I = I->Next)
136 if (I->Hash == Hash && InfoObj.EqualKey(I->Key, Key))
137 return true;
138 return false;
139 }
140
141 /// Emit the table to Out, which must not be at offset 0.
142 offset_type Emit(raw_ostream &Out) {
143 Info InfoObj;
144 return Emit(Out, InfoObj);
145 }
146
147 /// Emit the table to Out, which must not be at offset 0.
148 ///
149 /// Uses the provided Info instead of a stack allocated one.
150 offset_type Emit(raw_ostream &Out, Info &InfoObj) {
151 using namespace llvm::support;
152 endian::Writer LE(Out, little);
153
154 // Now we're done adding entries, resize the bucket list if it's
155 // significantly too large. (This only happens if the number of
156 // entries is small and we're within our initial allocation of
157 // 64 buckets.) We aim for an occupancy ratio in [3/8, 3/4).
158 //
159 // As a special case, if there are two or fewer entries, just
160 // form a single bucket. A linear scan is fine in that case, and
161 // this is very common in C++ class lookup tables. This also
162 // guarantees we produce at least one bucket for an empty table.
163 //
164 // FIXME: Try computing a perfect hash function at this point.
165 unsigned TargetNumBuckets =
166 NumEntries <= 2 ? 1 : llvm::bit_ceil(NumEntries * 4 / 3 + 1);
167 if (TargetNumBuckets != NumBuckets)
168 resize(TargetNumBuckets);
169
170 // Emit the payload of the table.
171 for (offset_type I = 0; I < NumBuckets; ++I) {
172 Bucket &B = Buckets[I];
173 if (!B.Head)
174 continue;
175
176 // Store the offset for the data of this bucket.
177 B.Off = Out.tell();
178 assert(B.Off && "Cannot write a bucket at offset 0. Please add padding.");
179
180 // Write out the number of items in the bucket.
181 LE.write<uint16_t>(B.Length);
182 assert(B.Length != 0 && "Bucket has a head but zero length?");
183
184 // Write out the entries in the bucket.
185 for (Item *I = B.Head; I; I = I->Next) {
186 LE.write<typename Info::hash_value_type>(I->Hash);
187 const std::pair<offset_type, offset_type> &Len =
188 InfoObj.EmitKeyDataLength(Out, I->Key, I->Data);
189#ifdef NDEBUG
190 InfoObj.EmitKey(Out, I->Key, Len.first);
191 InfoObj.EmitData(Out, I->Key, I->Data, Len.second);
192#else
193 // In asserts mode, check that the users length matches the data they
194 // wrote.
195 uint64_t KeyStart = Out.tell();
196 InfoObj.EmitKey(Out, I->Key, Len.first);
197 uint64_t DataStart = Out.tell();
198 InfoObj.EmitData(Out, I->Key, I->Data, Len.second);
199 uint64_t End = Out.tell();
200 assert(offset_type(DataStart - KeyStart) == Len.first &&
201 "key length does not match bytes written");
202 assert(offset_type(End - DataStart) == Len.second &&
203 "data length does not match bytes written");
204#endif
205 }
206 }
207
208 // Pad with zeros so that we can start the hashtable at an aligned address.
209 offset_type TableOff = Out.tell();
210 uint64_t N = offsetToAlignment(TableOff, Align(alignof(offset_type)));
211 TableOff += N;
212 while (N--)
213 LE.write<uint8_t>(0);
214
215 // Emit the hashtable itself.
216 LE.write<offset_type>(NumBuckets);
217 LE.write<offset_type>(NumEntries);
218 for (offset_type I = 0; I < NumBuckets; ++I)
219 LE.write<offset_type>(Buckets[I].Off);
220
221 return TableOff;
222 }
223
225 NumEntries = 0;
226 NumBuckets = 64;
227 // Note that we do not need to run the constructors of the individual
228 // Bucket objects since 'calloc' returns bytes that are all 0.
229 Buckets = static_cast<Bucket *>(safe_calloc(NumBuckets, sizeof(Bucket)));
230 }
231
232 ~OnDiskChainedHashTableGenerator() { std::free(Buckets); }
233};
234
235/// Provides lookup on an on disk hash table.
236///
237/// This needs an \c Info that handles reading values from the hash table's
238/// payload and computes the hash for a given key. This should provide the
239/// following interface:
240///
241/// \code
242/// class ExampleLookupInfo {
243/// public:
244/// typedef ExampleData data_type;
245/// typedef ExampleInternalKey internal_key_type; // The stored key type.
246/// typedef ExampleKey external_key_type; // The type to pass to find().
247/// typedef uint32_t hash_value_type; // The type the hash function returns.
248/// typedef uint32_t offset_type; // The type for offsets into the table.
249///
250/// /// Compare two keys for equality.
251/// static bool EqualKey(internal_key_type &Key1, internal_key_type &Key2);
252/// /// Calculate the hash for the given key.
253/// static hash_value_type ComputeHash(internal_key_type &IKey);
254/// /// Translate from the semantic type of a key in the hash table to the
255/// /// type that is actually stored and used for hashing and comparisons.
256/// /// The internal and external types are often the same, in which case this
257/// /// can simply return the passed in value.
258/// static const internal_key_type &GetInternalKey(external_key_type &EKey);
259/// /// Read the key and data length from Buffer, leaving it pointing at the
260/// /// following byte.
261/// static std::pair<offset_type, offset_type>
262/// ReadKeyDataLength(const unsigned char *&Buffer);
263/// /// Read the key from Buffer, given the KeyLen as reported from
264/// /// ReadKeyDataLength.
265/// const internal_key_type &ReadKey(const unsigned char *Buffer,
266/// offset_type KeyLen);
267/// /// Read the data for Key from Buffer, given the DataLen as reported from
268/// /// ReadKeyDataLength.
269/// data_type ReadData(StringRef Key, const unsigned char *Buffer,
270/// offset_type DataLen);
271/// };
272/// \endcode
273template <typename Info> class OnDiskChainedHashTable {
274 const typename Info::offset_type NumBuckets;
275 const typename Info::offset_type NumEntries;
276 const unsigned char *const Buckets;
277 const unsigned char *const Base;
278 Info InfoObj;
279
280public:
281 typedef Info InfoType;
282 typedef typename Info::internal_key_type internal_key_type;
283 typedef typename Info::external_key_type external_key_type;
284 typedef typename Info::data_type data_type;
285 typedef typename Info::hash_value_type hash_value_type;
286 typedef typename Info::offset_type offset_type;
287
289 const unsigned char *Buckets,
290 const unsigned char *Base,
291 const Info &InfoObj = Info())
292 : NumBuckets(NumBuckets), NumEntries(NumEntries), Buckets(Buckets),
293 Base(Base), InfoObj(InfoObj) {
294 assert((reinterpret_cast<uintptr_t>(Buckets) & 0x3) == 0 &&
295 "'buckets' must have a 4-byte alignment");
296 }
297
298 /// Read the number of buckets and the number of entries from a hash table
299 /// produced by OnDiskHashTableGenerator::Emit, and advance the Buckets
300 /// pointer past them.
301 static std::pair<offset_type, offset_type>
302 readNumBucketsAndEntries(const unsigned char *&Buckets) {
303 assert((reinterpret_cast<uintptr_t>(Buckets) & 0x3) == 0 &&
304 "buckets should be 4-byte aligned.");
305 using namespace llvm::support;
306 offset_type NumBuckets =
307 endian::readNext<offset_type, little, aligned>(Buckets);
308 offset_type NumEntries =
309 endian::readNext<offset_type, little, aligned>(Buckets);
310 return std::make_pair(NumBuckets, NumEntries);
311 }
312
313 offset_type getNumBuckets() const { return NumBuckets; }
314 offset_type getNumEntries() const { return NumEntries; }
315 const unsigned char *getBase() const { return Base; }
316 const unsigned char *getBuckets() const { return Buckets; }
317
318 bool isEmpty() const { return NumEntries == 0; }
319
320 class iterator {
322 const unsigned char *const Data;
323 const offset_type Len;
324 Info *InfoObj;
325
326 public:
327 iterator() : Key(), Data(nullptr), Len(0), InfoObj(nullptr) {}
328 iterator(const internal_key_type K, const unsigned char *D, offset_type L,
329 Info *InfoObj)
330 : Key(K), Data(D), Len(L), InfoObj(InfoObj) {}
331
332 data_type operator*() const { return InfoObj->ReadData(Key, Data, Len); }
333
334 const unsigned char *getDataPtr() const { return Data; }
335 offset_type getDataLen() const { return Len; }
336
337 bool operator==(const iterator &X) const { return X.Data == Data; }
338 bool operator!=(const iterator &X) const { return X.Data != Data; }
339 };
340
341 /// Look up the stored data for a particular key.
342 iterator find(const external_key_type &EKey, Info *InfoPtr = nullptr) {
343 const internal_key_type &IKey = InfoObj.GetInternalKey(EKey);
344 hash_value_type KeyHash = InfoObj.ComputeHash(IKey);
345 return find_hashed(IKey, KeyHash, InfoPtr);
346 }
347
348 /// Look up the stored data for a particular key with a known hash.
350 Info *InfoPtr = nullptr) {
351 using namespace llvm::support;
352
353 if (!InfoPtr)
354 InfoPtr = &InfoObj;
355
356 // Each bucket is just an offset into the hash table file.
357 offset_type Idx = KeyHash & (NumBuckets - 1);
358 const unsigned char *Bucket = Buckets + sizeof(offset_type) * Idx;
359
360 offset_type Offset = endian::readNext<offset_type, little, aligned>(Bucket);
361 if (Offset == 0)
362 return iterator(); // Empty bucket.
363 const unsigned char *Items = Base + Offset;
364
365 // 'Items' starts with a 16-bit unsigned integer representing the
366 // number of items in this bucket.
367 unsigned Len = endian::readNext<uint16_t, little, unaligned>(Items);
368
369 for (unsigned i = 0; i < Len; ++i) {
370 // Read the hash.
371 hash_value_type ItemHash =
372 endian::readNext<hash_value_type, little, unaligned>(Items);
373
374 // Determine the length of the key and the data.
375 const std::pair<offset_type, offset_type> &L =
376 Info::ReadKeyDataLength(Items);
377 offset_type ItemLen = L.first + L.second;
378
379 // Compare the hashes. If they are not the same, skip the entry entirely.
380 if (ItemHash != KeyHash) {
381 Items += ItemLen;
382 continue;
383 }
384
385 // Read the key.
386 const internal_key_type &X =
387 InfoPtr->ReadKey((const unsigned char *const)Items, L.first);
388
389 // If the key doesn't match just skip reading the value.
390 if (!InfoPtr->EqualKey(X, IKey)) {
391 Items += ItemLen;
392 continue;
393 }
394
395 // The key matches!
396 return iterator(X, Items + L.first, L.second, InfoPtr);
397 }
398
399 return iterator();
400 }
401
402 iterator end() const { return iterator(); }
403
404 Info &getInfoObj() { return InfoObj; }
405
406 /// Create the hash table.
407 ///
408 /// \param Buckets is the beginning of the hash table itself, which follows
409 /// the payload of entire structure. This is the value returned by
410 /// OnDiskHashTableGenerator::Emit.
411 ///
412 /// \param Base is the point from which all offsets into the structure are
413 /// based. This is offset 0 in the stream that was used when Emitting the
414 /// table.
415 static OnDiskChainedHashTable *Create(const unsigned char *Buckets,
416 const unsigned char *const Base,
417 const Info &InfoObj = Info()) {
418 assert(Buckets > Base);
419 auto NumBucketsAndEntries = readNumBucketsAndEntries(Buckets);
420 return new OnDiskChainedHashTable<Info>(NumBucketsAndEntries.first,
421 NumBucketsAndEntries.second,
422 Buckets, Base, InfoObj);
423 }
424};
425
426/// Provides lookup and iteration over an on disk hash table.
427///
428/// \copydetails llvm::OnDiskChainedHashTable
429template <typename Info>
431 const unsigned char *Payload;
432
433public:
440
441private:
442 /// Iterates over all of the keys in the table.
443 class iterator_base {
444 const unsigned char *Ptr;
445 offset_type NumItemsInBucketLeft;
446 offset_type NumEntriesLeft;
447
448 public:
449 typedef external_key_type value_type;
450
451 iterator_base(const unsigned char *const Ptr, offset_type NumEntries)
452 : Ptr(Ptr), NumItemsInBucketLeft(0), NumEntriesLeft(NumEntries) {}
453 iterator_base()
454 : Ptr(nullptr), NumItemsInBucketLeft(0), NumEntriesLeft(0) {}
455
456 friend bool operator==(const iterator_base &X, const iterator_base &Y) {
457 return X.NumEntriesLeft == Y.NumEntriesLeft;
458 }
459 friend bool operator!=(const iterator_base &X, const iterator_base &Y) {
460 return X.NumEntriesLeft != Y.NumEntriesLeft;
461 }
462
463 /// Move to the next item.
464 void advance() {
465 using namespace llvm::support;
466 if (!NumItemsInBucketLeft) {
467 // 'Items' starts with a 16-bit unsigned integer representing the
468 // number of items in this bucket.
469 NumItemsInBucketLeft =
470 endian::readNext<uint16_t, little, unaligned>(Ptr);
471 }
472 Ptr += sizeof(hash_value_type); // Skip the hash.
473 // Determine the length of the key and the data.
474 const std::pair<offset_type, offset_type> &L =
475 Info::ReadKeyDataLength(Ptr);
476 Ptr += L.first + L.second;
477 assert(NumItemsInBucketLeft);
478 --NumItemsInBucketLeft;
479 assert(NumEntriesLeft);
480 --NumEntriesLeft;
481 }
482
483 /// Get the start of the item as written by the trait (after the hash and
484 /// immediately before the key and value length).
485 const unsigned char *getItem() const {
486 return Ptr + (NumItemsInBucketLeft ? 0 : 2) + sizeof(hash_value_type);
487 }
488 };
489
490public:
492 const unsigned char *Buckets,
493 const unsigned char *Payload,
494 const unsigned char *Base,
495 const Info &InfoObj = Info())
496 : base_type(NumBuckets, NumEntries, Buckets, Base, InfoObj),
497 Payload(Payload) {}
498
499 /// Iterates over all of the keys in the table.
500 class key_iterator : public iterator_base {
501 Info *InfoObj;
502
503 public:
505
506 key_iterator(const unsigned char *const Ptr, offset_type NumEntries,
507 Info *InfoObj)
508 : iterator_base(Ptr, NumEntries), InfoObj(InfoObj) {}
509 key_iterator() : iterator_base(), InfoObj() {}
510
512 this->advance();
513 return *this;
514 }
515 key_iterator operator++(int) { // Postincrement
516 key_iterator tmp = *this;
517 ++*this;
518 return tmp;
519 }
520
522 auto *LocalPtr = this->getItem();
523
524 // Determine the length of the key and the data.
525 auto L = Info::ReadKeyDataLength(LocalPtr);
526
527 // Read the key.
528 return InfoObj->ReadKey(LocalPtr, L.first);
529 }
530
532 return InfoObj->GetExternalKey(getInternalKey());
533 }
534 };
535
537 return key_iterator(Payload, this->getNumEntries(), &this->getInfoObj());
538 }
540
542 return make_range(key_begin(), key_end());
543 }
544
545 /// Iterates over all the entries in the table, returning the data.
546 class data_iterator : public iterator_base {
547 Info *InfoObj;
548
549 public:
551
552 data_iterator(const unsigned char *const Ptr, offset_type NumEntries,
553 Info *InfoObj)
554 : iterator_base(Ptr, NumEntries), InfoObj(InfoObj) {}
555 data_iterator() : iterator_base(), InfoObj() {}
556
557 data_iterator &operator++() { // Preincrement
558 this->advance();
559 return *this;
560 }
561 data_iterator operator++(int) { // Postincrement
562 data_iterator tmp = *this;
563 ++*this;
564 return tmp;
565 }
566
568 auto *LocalPtr = this->getItem();
569
570 // Determine the length of the key and the data.
571 auto L = Info::ReadKeyDataLength(LocalPtr);
572
573 // Read the key.
574 const internal_key_type &Key = InfoObj->ReadKey(LocalPtr, L.first);
575 return InfoObj->ReadData(Key, LocalPtr + L.first, L.second);
576 }
577 };
578
580 return data_iterator(Payload, this->getNumEntries(), &this->getInfoObj());
581 }
583
585 return make_range(data_begin(), data_end());
586 }
587
588 /// Create the hash table.
589 ///
590 /// \param Buckets is the beginning of the hash table itself, which follows
591 /// the payload of entire structure. This is the value returned by
592 /// OnDiskHashTableGenerator::Emit.
593 ///
594 /// \param Payload is the beginning of the data contained in the table. This
595 /// is Base plus any padding or header data that was stored, ie, the offset
596 /// that the stream was at when calling Emit.
597 ///
598 /// \param Base is the point from which all offsets into the structure are
599 /// based. This is offset 0 in the stream that was used when Emitting the
600 /// table.
602 Create(const unsigned char *Buckets, const unsigned char *const Payload,
603 const unsigned char *const Base, const Info &InfoObj = Info()) {
604 assert(Buckets > Base);
605 auto NumBucketsAndEntries =
608 NumBucketsAndEntries.first, NumBucketsAndEntries.second,
609 Buckets, Payload, Base, InfoObj);
610 }
611};
612
613} // end namespace llvm
614
615#endif
This file defines the BumpPtrAllocator interface.
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
Analysis containing CSE Info
Definition: CSEInfo.cpp:27
dxil metadata DXIL Metadata Emit
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
uint64_t Size
bool End
Definition: ELF_riscv.cpp:469
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
#define I(x, y, z)
Definition: MD5.cpp:58
static GCMetadataPrinterRegistry::Add< OcamlGCMetadataPrinter > Y("ocaml", "ocaml 3.10-compatible collector")
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
Generates an on disk hash table.
offset_type Emit(raw_ostream &Out)
Emit the table to Out, which must not be at offset 0.
void insert(typename Info::key_type_ref Key, typename Info::data_type_ref Data)
Insert an entry into the table.
bool contains(typename Info::key_type_ref Key, Info &InfoObj)
Determine whether an entry has been inserted.
offset_type Emit(raw_ostream &Out, Info &InfoObj)
Emit the table to Out, which must not be at offset 0.
void insert(typename Info::key_type_ref Key, typename Info::data_type_ref Data, Info &InfoObj)
Insert an entry into the table.
const unsigned char * getDataPtr() const
bool operator==(const iterator &X) const
bool operator!=(const iterator &X) const
iterator(const internal_key_type K, const unsigned char *D, offset_type L, Info *InfoObj)
Provides lookup on an on disk hash table.
static std::pair< offset_type, offset_type > readNumBucketsAndEntries(const unsigned char *&Buckets)
Read the number of buckets and the number of entries from a hash table produced by OnDiskHashTableGen...
Info::hash_value_type hash_value_type
static OnDiskChainedHashTable * Create(const unsigned char *Buckets, const unsigned char *const Base, const Info &InfoObj=Info())
Create the hash table.
offset_type getNumEntries() const
iterator find_hashed(const internal_key_type &IKey, hash_value_type KeyHash, Info *InfoPtr=nullptr)
Look up the stored data for a particular key with a known hash.
offset_type getNumBuckets() const
Info::external_key_type external_key_type
Info::internal_key_type internal_key_type
const unsigned char * getBase() const
const unsigned char * getBuckets() const
iterator find(const external_key_type &EKey, Info *InfoPtr=nullptr)
Look up the stored data for a particular key.
OnDiskChainedHashTable(offset_type NumBuckets, offset_type NumEntries, const unsigned char *Buckets, const unsigned char *Base, const Info &InfoObj=Info())
Iterates over all the entries in the table, returning the data.
data_iterator(const unsigned char *const Ptr, offset_type NumEntries, Info *InfoObj)
Iterates over all of the keys in the table.
key_iterator(const unsigned char *const Ptr, offset_type NumEntries, Info *InfoObj)
Provides lookup and iteration over an on disk hash table.
iterator_range< key_iterator > keys()
static OnDiskIterableChainedHashTable * Create(const unsigned char *Buckets, const unsigned char *const Payload, const unsigned char *const Base, const Info &InfoObj=Info())
Create the hash table.
base_type::internal_key_type internal_key_type
base_type::external_key_type external_key_type
iterator_range< data_iterator > data()
base_type::hash_value_type hash_value_type
OnDiskIterableChainedHashTable(offset_type NumBuckets, offset_type NumEntries, const unsigned char *Buckets, const unsigned char *Payload, const unsigned char *Base, const Info &InfoObj=Info())
OnDiskChainedHashTable< Info > base_type
A BumpPtrAllocator that allows only elements of a specific type to be allocated.
Definition: Allocator.h:382
T * Allocate(size_t num=1)
Allocate space for an array of objects without constructing them.
Definition: Allocator.h:432
A range adaptor for a pair of iterators.
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
uint64_t tell() const
tell - Return the current offset with the file.
Definition: raw_ostream.h:134
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:440
@ Length
Definition: DWP.cpp:440
bool operator!=(uint64_t V1, const APInt &V2)
Definition: APInt.h:2036
iterator_range< T > make_range(T x, T y)
Convenience function for iterating over sub-ranges.
T bit_ceil(T Value)
Returns the smallest integral power of two no smaller than Value if Value is nonzero.
Definition: bit.h:306
bool operator==(const AddressRangeValuePair &LHS, const AddressRangeValuePair &RHS)
LLVM_ATTRIBUTE_RETURNS_NONNULL void * safe_calloc(size_t Count, size_t Sz)
Definition: MemAlloc.h:38
uint64_t offsetToAlignment(uint64_t Value, Align Alignment)
Returns the offset to the next integer (mod 2**64) that is greater than or equal to Value and is a mu...
Definition: Alignment.h:197
#define N
This struct is a compact representation of a valid (non-zero power of two) alignment.
Definition: Alignment.h:39
Adapter to write values to a stream in a particular byte order.
Definition: EndianStream.h:68