LLVM 20.0.0git
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;
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, llvm::endianness::little, aligned>(
308 Buckets);
309 offset_type NumEntries =
310 endian::readNext<offset_type, llvm::endianness::little, aligned>(
311 Buckets);
312 return std::make_pair(NumBuckets, NumEntries);
313 }
314
315 offset_type getNumBuckets() const { return NumBuckets; }
316 offset_type getNumEntries() const { return NumEntries; }
317 const unsigned char *getBase() const { return Base; }
318 const unsigned char *getBuckets() const { return Buckets; }
319
320 bool isEmpty() const { return NumEntries == 0; }
321
322 class iterator {
324 const unsigned char *const Data;
325 const offset_type Len;
326 Info *InfoObj;
327
328 public:
329 iterator() : Key(), Data(nullptr), Len(0), InfoObj(nullptr) {}
330 iterator(const internal_key_type K, const unsigned char *D, offset_type L,
331 Info *InfoObj)
332 : Key(K), Data(D), Len(L), InfoObj(InfoObj) {}
333
334 data_type operator*() const { return InfoObj->ReadData(Key, Data, Len); }
335
336 const unsigned char *getDataPtr() const { return Data; }
337 offset_type getDataLen() const { return Len; }
338
339 bool operator==(const iterator &X) const { return X.Data == Data; }
340 bool operator!=(const iterator &X) const { return X.Data != Data; }
341 };
342
343 /// Look up the stored data for a particular key.
344 iterator find(const external_key_type &EKey, Info *InfoPtr = nullptr) {
345 const internal_key_type &IKey = InfoObj.GetInternalKey(EKey);
346 hash_value_type KeyHash = InfoObj.ComputeHash(IKey);
347 return find_hashed(IKey, KeyHash, InfoPtr);
348 }
349
350 /// Look up the stored data for a particular key with a known hash.
352 Info *InfoPtr = nullptr) {
353 using namespace llvm::support;
354
355 if (!InfoPtr)
356 InfoPtr = &InfoObj;
357
358 // Each bucket is just an offset into the hash table file.
359 offset_type Idx = KeyHash & (NumBuckets - 1);
360 const unsigned char *Bucket = Buckets + sizeof(offset_type) * Idx;
361
363 endian::readNext<offset_type, llvm::endianness::little, aligned>(
364 Bucket);
365 if (Offset == 0)
366 return iterator(); // Empty bucket.
367 const unsigned char *Items = Base + Offset;
368
369 // 'Items' starts with a 16-bit unsigned integer representing the
370 // number of items in this bucket.
371 unsigned Len = endian::readNext<uint16_t, llvm::endianness::little>(Items);
372
373 for (unsigned i = 0; i < Len; ++i) {
374 // Read the hash.
375 hash_value_type ItemHash =
376 endian::readNext<hash_value_type, llvm::endianness::little>(Items);
377
378 // Determine the length of the key and the data.
379 const std::pair<offset_type, offset_type> &L =
380 Info::ReadKeyDataLength(Items);
381 offset_type ItemLen = L.first + L.second;
382
383 // Compare the hashes. If they are not the same, skip the entry entirely.
384 if (ItemHash != KeyHash) {
385 Items += ItemLen;
386 continue;
387 }
388
389 // Read the key.
390 const internal_key_type &X =
391 InfoPtr->ReadKey((const unsigned char *const)Items, L.first);
392
393 // If the key doesn't match just skip reading the value.
394 if (!InfoPtr->EqualKey(X, IKey)) {
395 Items += ItemLen;
396 continue;
397 }
398
399 // The key matches!
400 return iterator(X, Items + L.first, L.second, InfoPtr);
401 }
402
403 return iterator();
404 }
405
406 iterator end() const { return iterator(); }
407
408 Info &getInfoObj() { return InfoObj; }
409
410 /// Create the hash table.
411 ///
412 /// \param Buckets is the beginning of the hash table itself, which follows
413 /// the payload of entire structure. This is the value returned by
414 /// OnDiskHashTableGenerator::Emit.
415 ///
416 /// \param Base is the point from which all offsets into the structure are
417 /// based. This is offset 0 in the stream that was used when Emitting the
418 /// table.
419 static OnDiskChainedHashTable *Create(const unsigned char *Buckets,
420 const unsigned char *const Base,
421 const Info &InfoObj = Info()) {
422 assert(Buckets > Base);
423 auto NumBucketsAndEntries = readNumBucketsAndEntries(Buckets);
424 return new OnDiskChainedHashTable<Info>(NumBucketsAndEntries.first,
425 NumBucketsAndEntries.second,
426 Buckets, Base, InfoObj);
427 }
428};
429
430/// Provides lookup and iteration over an on disk hash table.
431///
432/// \copydetails llvm::OnDiskChainedHashTable
433template <typename Info>
435 const unsigned char *Payload;
436
437public:
444
445private:
446 /// Iterates over all of the keys in the table.
447 class iterator_base {
448 const unsigned char *Ptr;
449 offset_type NumItemsInBucketLeft;
450 offset_type NumEntriesLeft;
451
452 public:
453 typedef external_key_type value_type;
454
455 iterator_base(const unsigned char *const Ptr, offset_type NumEntries)
456 : Ptr(Ptr), NumItemsInBucketLeft(0), NumEntriesLeft(NumEntries) {}
457 iterator_base()
458 : Ptr(nullptr), NumItemsInBucketLeft(0), NumEntriesLeft(0) {}
459
460 friend bool operator==(const iterator_base &X, const iterator_base &Y) {
461 return X.NumEntriesLeft == Y.NumEntriesLeft;
462 }
463 friend bool operator!=(const iterator_base &X, const iterator_base &Y) {
464 return X.NumEntriesLeft != Y.NumEntriesLeft;
465 }
466
467 /// Move to the next item.
468 void advance() {
469 using namespace llvm::support;
470 if (!NumItemsInBucketLeft) {
471 // 'Items' starts with a 16-bit unsigned integer representing the
472 // number of items in this bucket.
473 NumItemsInBucketLeft =
474 endian::readNext<uint16_t, llvm::endianness::little>(Ptr);
475 }
476 Ptr += sizeof(hash_value_type); // Skip the hash.
477 // Determine the length of the key and the data.
478 const std::pair<offset_type, offset_type> &L =
479 Info::ReadKeyDataLength(Ptr);
480 Ptr += L.first + L.second;
481 assert(NumItemsInBucketLeft);
482 --NumItemsInBucketLeft;
483 assert(NumEntriesLeft);
484 --NumEntriesLeft;
485 }
486
487 /// Get the start of the item as written by the trait (after the hash and
488 /// immediately before the key and value length).
489 const unsigned char *getItem() const {
490 return Ptr + (NumItemsInBucketLeft ? 0 : 2) + sizeof(hash_value_type);
491 }
492 };
493
494public:
496 const unsigned char *Buckets,
497 const unsigned char *Payload,
498 const unsigned char *Base,
499 const Info &InfoObj = Info())
500 : base_type(NumBuckets, NumEntries, Buckets, Base, InfoObj),
501 Payload(Payload) {}
502
503 /// Iterates over all of the keys in the table.
504 class key_iterator : public iterator_base {
505 Info *InfoObj;
506
507 public:
509
510 key_iterator(const unsigned char *const Ptr, offset_type NumEntries,
511 Info *InfoObj)
512 : iterator_base(Ptr, NumEntries), InfoObj(InfoObj) {}
513 key_iterator() : iterator_base(), InfoObj() {}
514
516 this->advance();
517 return *this;
518 }
519 key_iterator operator++(int) { // Postincrement
520 key_iterator tmp = *this;
521 ++*this;
522 return tmp;
523 }
524
526 auto *LocalPtr = this->getItem();
527
528 // Determine the length of the key and the data.
529 auto L = Info::ReadKeyDataLength(LocalPtr);
530
531 // Read the key.
532 return InfoObj->ReadKey(LocalPtr, L.first);
533 }
534
536 return InfoObj->GetExternalKey(getInternalKey());
537 }
538 };
539
541 return key_iterator(Payload, this->getNumEntries(), &this->getInfoObj());
542 }
544
546 return make_range(key_begin(), key_end());
547 }
548
549 /// Iterates over all the entries in the table, returning the data.
550 class data_iterator : public iterator_base {
551 Info *InfoObj;
552
553 public:
555
556 data_iterator(const unsigned char *const Ptr, offset_type NumEntries,
557 Info *InfoObj)
558 : iterator_base(Ptr, NumEntries), InfoObj(InfoObj) {}
559 data_iterator() : iterator_base(), InfoObj() {}
560
561 data_iterator &operator++() { // Preincrement
562 this->advance();
563 return *this;
564 }
565 data_iterator operator++(int) { // Postincrement
566 data_iterator tmp = *this;
567 ++*this;
568 return tmp;
569 }
570
572 auto *LocalPtr = this->getItem();
573
574 // Determine the length of the key and the data.
575 auto L = Info::ReadKeyDataLength(LocalPtr);
576
577 // Read the key.
578 const internal_key_type &Key = InfoObj->ReadKey(LocalPtr, L.first);
579 return InfoObj->ReadData(Key, LocalPtr + L.first, L.second);
580 }
581 };
582
584 return data_iterator(Payload, this->getNumEntries(), &this->getInfoObj());
585 }
587
589 return make_range(data_begin(), data_end());
590 }
591
592 /// Create the hash table.
593 ///
594 /// \param Buckets is the beginning of the hash table itself, which follows
595 /// the payload of entire structure. This is the value returned by
596 /// OnDiskHashTableGenerator::Emit.
597 ///
598 /// \param Payload is the beginning of the data contained in the table. This
599 /// is Base plus any padding or header data that was stored, ie, the offset
600 /// that the stream was at when calling Emit.
601 ///
602 /// \param Base is the point from which all offsets into the structure are
603 /// based. This is offset 0 in the stream that was used when Emitting the
604 /// table.
606 Create(const unsigned char *Buckets, const unsigned char *const Payload,
607 const unsigned char *const Base, const Info &InfoObj = Info()) {
608 assert(Buckets > Base);
609 auto NumBucketsAndEntries =
612 NumBucketsAndEntries.first, NumBucketsAndEntries.second,
613 Buckets, Payload, Base, InfoObj);
614 }
615};
616
617} // end namespace llvm
618
619#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
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:480
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:389
T * Allocate(size_t num=1)
Allocate space for an array of objects without constructing them.
Definition: Allocator.h:439
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:147
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:480
@ Length
Definition: DWP.cpp:480
bool operator!=(uint64_t V1, const APInt &V2)
Definition: APInt.h:2052
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:342
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:67