mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-23 15:29:51 +00:00
08c09496c2
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53067 91177308-0d34-0410-b5e6-96231b3b80d8
459 lines
15 KiB
C++
459 lines
15 KiB
C++
//===- llvm/ADT/DenseMap.h - Dense probed hash table ------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file defines the DenseMap class.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_ADT_DENSEMAP_H
|
|
#define LLVM_ADT_DENSEMAP_H
|
|
|
|
#include "llvm/Support/DataTypes.h"
|
|
#include "llvm/Support/MathExtras.h"
|
|
#include <cassert>
|
|
#include <utility>
|
|
|
|
namespace llvm {
|
|
|
|
template<typename T>
|
|
struct DenseMapInfo {
|
|
//static inline T getEmptyKey();
|
|
//static inline T getTombstoneKey();
|
|
//static unsigned getHashValue(const T &Val);
|
|
//static bool isEqual(const T &LHS, const T &RHS);
|
|
//static bool isPod()
|
|
};
|
|
|
|
// Provide DenseMapInfo for all pointers.
|
|
template<typename T>
|
|
struct DenseMapInfo<T*> {
|
|
static inline T* getEmptyKey() { return reinterpret_cast<T*>(-1); }
|
|
static inline T* getTombstoneKey() { return reinterpret_cast<T*>(-2); }
|
|
static unsigned getHashValue(const T *PtrVal) {
|
|
return (unsigned((uintptr_t)PtrVal) >> 4) ^
|
|
(unsigned((uintptr_t)PtrVal) >> 9);
|
|
}
|
|
static bool isEqual(const T *LHS, const T *RHS) { return LHS == RHS; }
|
|
static bool isPod() { return true; }
|
|
};
|
|
|
|
template<typename KeyT, typename ValueT,
|
|
typename KeyInfoT = DenseMapInfo<KeyT>,
|
|
typename ValueInfoT = DenseMapInfo<ValueT> >
|
|
class DenseMapIterator;
|
|
template<typename KeyT, typename ValueT,
|
|
typename KeyInfoT = DenseMapInfo<KeyT>,
|
|
typename ValueInfoT = DenseMapInfo<ValueT> >
|
|
class DenseMapConstIterator;
|
|
|
|
template<typename KeyT, typename ValueT,
|
|
typename KeyInfoT = DenseMapInfo<KeyT>,
|
|
typename ValueInfoT = DenseMapInfo<ValueT> >
|
|
class DenseMap {
|
|
typedef std::pair<KeyT, ValueT> BucketT;
|
|
unsigned NumBuckets;
|
|
BucketT *Buckets;
|
|
|
|
unsigned NumEntries;
|
|
unsigned NumTombstones;
|
|
public:
|
|
typedef BucketT value_type;
|
|
|
|
DenseMap(const DenseMap& other) {
|
|
NumBuckets = 0;
|
|
CopyFrom(other);
|
|
}
|
|
|
|
explicit DenseMap(unsigned NumInitBuckets = 64) {
|
|
init(NumInitBuckets);
|
|
}
|
|
|
|
~DenseMap() {
|
|
const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey();
|
|
for (BucketT *P = Buckets, *E = Buckets+NumBuckets; P != E; ++P) {
|
|
if (!KeyInfoT::isEqual(P->first, EmptyKey) &&
|
|
!KeyInfoT::isEqual(P->first, TombstoneKey))
|
|
P->second.~ValueT();
|
|
P->first.~KeyT();
|
|
}
|
|
operator delete(Buckets);
|
|
}
|
|
|
|
typedef DenseMapIterator<KeyT, ValueT, KeyInfoT> iterator;
|
|
typedef DenseMapConstIterator<KeyT, ValueT, KeyInfoT> const_iterator;
|
|
inline iterator begin() {
|
|
return iterator(Buckets, Buckets+NumBuckets);
|
|
}
|
|
inline iterator end() {
|
|
return iterator(Buckets+NumBuckets, Buckets+NumBuckets);
|
|
}
|
|
inline const_iterator begin() const {
|
|
return const_iterator(Buckets, Buckets+NumBuckets);
|
|
}
|
|
inline const_iterator end() const {
|
|
return const_iterator(Buckets+NumBuckets, Buckets+NumBuckets);
|
|
}
|
|
|
|
bool empty() const { return NumEntries == 0; }
|
|
unsigned size() const { return NumEntries; }
|
|
|
|
/// Grow the densemap so that it has at least Size buckets. Does not shrink
|
|
void resize(size_t Size) { grow(Size); }
|
|
|
|
void clear() {
|
|
// If the capacity of the array is huge, and the # elements used is small,
|
|
// shrink the array.
|
|
if (NumEntries * 4 < NumBuckets && NumBuckets > 64) {
|
|
shrink_and_clear();
|
|
return;
|
|
}
|
|
|
|
const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey();
|
|
for (BucketT *P = Buckets, *E = Buckets+NumBuckets; P != E; ++P) {
|
|
if (!KeyInfoT::isEqual(P->first, EmptyKey)) {
|
|
if (!KeyInfoT::isEqual(P->first, TombstoneKey)) {
|
|
P->second.~ValueT();
|
|
--NumEntries;
|
|
}
|
|
P->first = EmptyKey;
|
|
}
|
|
}
|
|
assert(NumEntries == 0 && "Node count imbalance!");
|
|
NumTombstones = 0;
|
|
}
|
|
|
|
/// count - Return true if the specified key is in the map.
|
|
bool count(const KeyT &Val) const {
|
|
BucketT *TheBucket;
|
|
return LookupBucketFor(Val, TheBucket);
|
|
}
|
|
|
|
iterator find(const KeyT &Val) {
|
|
BucketT *TheBucket;
|
|
if (LookupBucketFor(Val, TheBucket))
|
|
return iterator(TheBucket, Buckets+NumBuckets);
|
|
return end();
|
|
}
|
|
const_iterator find(const KeyT &Val) const {
|
|
BucketT *TheBucket;
|
|
if (LookupBucketFor(Val, TheBucket))
|
|
return const_iterator(TheBucket, Buckets+NumBuckets);
|
|
return end();
|
|
}
|
|
|
|
bool insert(const std::pair<KeyT, ValueT> &KV) {
|
|
BucketT *TheBucket;
|
|
if (LookupBucketFor(KV.first, TheBucket))
|
|
return false; // Already in map.
|
|
|
|
// Otherwise, insert the new element.
|
|
InsertIntoBucket(KV.first, KV.second, TheBucket);
|
|
return true;
|
|
}
|
|
|
|
bool erase(const KeyT &Val) {
|
|
BucketT *TheBucket;
|
|
if (!LookupBucketFor(Val, TheBucket))
|
|
return false; // not in map.
|
|
|
|
TheBucket->second.~ValueT();
|
|
TheBucket->first = getTombstoneKey();
|
|
--NumEntries;
|
|
++NumTombstones;
|
|
return true;
|
|
}
|
|
bool erase(iterator I) {
|
|
BucketT *TheBucket = &*I;
|
|
TheBucket->second.~ValueT();
|
|
TheBucket->first = getTombstoneKey();
|
|
--NumEntries;
|
|
++NumTombstones;
|
|
return true;
|
|
}
|
|
|
|
value_type& FindAndConstruct(const KeyT &Key) {
|
|
BucketT *TheBucket;
|
|
if (LookupBucketFor(Key, TheBucket))
|
|
return *TheBucket;
|
|
|
|
return *InsertIntoBucket(Key, ValueT(), TheBucket);
|
|
}
|
|
|
|
ValueT &operator[](const KeyT &Key) {
|
|
return FindAndConstruct(Key).second;
|
|
}
|
|
|
|
DenseMap& operator=(const DenseMap& other) {
|
|
CopyFrom(other);
|
|
return *this;
|
|
}
|
|
|
|
private:
|
|
void CopyFrom(const DenseMap& other) {
|
|
if (NumBuckets != 0 && (!KeyInfoT::isPod() || !ValueInfoT::isPod())) {
|
|
const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey();
|
|
for (BucketT *P = Buckets, *E = Buckets+NumBuckets; P != E; ++P) {
|
|
if (!KeyInfoT::isEqual(P->first, EmptyKey) &&
|
|
!KeyInfoT::isEqual(P->first, TombstoneKey))
|
|
P->second.~ValueT();
|
|
P->first.~KeyT();
|
|
}
|
|
}
|
|
|
|
NumEntries = other.NumEntries;
|
|
NumTombstones = other.NumTombstones;
|
|
|
|
if (NumBuckets)
|
|
operator delete(Buckets);
|
|
Buckets = static_cast<BucketT*>(operator new(sizeof(BucketT) *
|
|
other.NumBuckets));
|
|
|
|
if (KeyInfoT::isPod() && ValueInfoT::isPod())
|
|
memcpy(Buckets, other.Buckets, other.NumBuckets * sizeof(BucketT));
|
|
else
|
|
for (size_t i = 0; i < other.NumBuckets; ++i) {
|
|
new (&Buckets[i].first) KeyT(other.Buckets[i].first);
|
|
if (!KeyInfoT::isEqual(Buckets[i].first, getEmptyKey()) &&
|
|
!KeyInfoT::isEqual(Buckets[i].first, getTombstoneKey()))
|
|
new (&Buckets[i].second) ValueT(other.Buckets[i].second);
|
|
}
|
|
NumBuckets = other.NumBuckets;
|
|
}
|
|
|
|
BucketT *InsertIntoBucket(const KeyT &Key, const ValueT &Value,
|
|
BucketT *TheBucket) {
|
|
// If the load of the hash table is more than 3/4, or if fewer than 1/8 of
|
|
// the buckets are empty (meaning that many are filled with tombstones),
|
|
// grow the table.
|
|
//
|
|
// The later case is tricky. For example, if we had one empty bucket with
|
|
// tons of tombstones, failing lookups (e.g. for insertion) would have to
|
|
// probe almost the entire table until it found the empty bucket. If the
|
|
// table completely filled with tombstones, no lookup would ever succeed,
|
|
// causing infinite loops in lookup.
|
|
if (NumEntries*4 >= NumBuckets*3 ||
|
|
NumBuckets-(NumEntries+NumTombstones) < NumBuckets/8) {
|
|
this->grow(NumBuckets * 2);
|
|
LookupBucketFor(Key, TheBucket);
|
|
}
|
|
++NumEntries;
|
|
|
|
// If we are writing over a tombstone, remember this.
|
|
if (!KeyInfoT::isEqual(TheBucket->first, getEmptyKey()))
|
|
--NumTombstones;
|
|
|
|
TheBucket->first = Key;
|
|
new (&TheBucket->second) ValueT(Value);
|
|
return TheBucket;
|
|
}
|
|
|
|
static unsigned getHashValue(const KeyT &Val) {
|
|
return KeyInfoT::getHashValue(Val);
|
|
}
|
|
static const KeyT getEmptyKey() {
|
|
return KeyInfoT::getEmptyKey();
|
|
}
|
|
static const KeyT getTombstoneKey() {
|
|
return KeyInfoT::getTombstoneKey();
|
|
}
|
|
|
|
/// LookupBucketFor - Lookup the appropriate bucket for Val, returning it in
|
|
/// FoundBucket. If the bucket contains the key and a value, this returns
|
|
/// true, otherwise it returns a bucket with an empty marker or tombstone and
|
|
/// returns false.
|
|
bool LookupBucketFor(const KeyT &Val, BucketT *&FoundBucket) const {
|
|
unsigned BucketNo = getHashValue(Val);
|
|
unsigned ProbeAmt = 1;
|
|
BucketT *BucketsPtr = Buckets;
|
|
|
|
// FoundTombstone - Keep track of whether we find a tombstone while probing.
|
|
BucketT *FoundTombstone = 0;
|
|
const KeyT EmptyKey = getEmptyKey();
|
|
const KeyT TombstoneKey = getTombstoneKey();
|
|
assert(!KeyInfoT::isEqual(Val, EmptyKey) &&
|
|
!KeyInfoT::isEqual(Val, TombstoneKey) &&
|
|
"Empty/Tombstone value shouldn't be inserted into map!");
|
|
|
|
while (1) {
|
|
BucketT *ThisBucket = BucketsPtr + (BucketNo & (NumBuckets-1));
|
|
// Found Val's bucket? If so, return it.
|
|
if (KeyInfoT::isEqual(ThisBucket->first, Val)) {
|
|
FoundBucket = ThisBucket;
|
|
return true;
|
|
}
|
|
|
|
// If we found an empty bucket, the key doesn't exist in the set.
|
|
// Insert it and return the default value.
|
|
if (KeyInfoT::isEqual(ThisBucket->first, EmptyKey)) {
|
|
// If we've already seen a tombstone while probing, fill it in instead
|
|
// of the empty bucket we eventually probed to.
|
|
if (FoundTombstone) ThisBucket = FoundTombstone;
|
|
FoundBucket = FoundTombstone ? FoundTombstone : ThisBucket;
|
|
return false;
|
|
}
|
|
|
|
// If this is a tombstone, remember it. If Val ends up not in the map, we
|
|
// prefer to return it than something that would require more probing.
|
|
if (KeyInfoT::isEqual(ThisBucket->first, TombstoneKey) && !FoundTombstone)
|
|
FoundTombstone = ThisBucket; // Remember the first tombstone found.
|
|
|
|
// Otherwise, it's a hash collision or a tombstone, continue quadratic
|
|
// probing.
|
|
BucketNo += ProbeAmt++;
|
|
}
|
|
}
|
|
|
|
void init(unsigned InitBuckets) {
|
|
NumEntries = 0;
|
|
NumTombstones = 0;
|
|
NumBuckets = InitBuckets;
|
|
assert(InitBuckets && (InitBuckets & (InitBuckets-1)) == 0 &&
|
|
"# initial buckets must be a power of two!");
|
|
Buckets = static_cast<BucketT*>(operator new(sizeof(BucketT)*InitBuckets));
|
|
// Initialize all the keys to EmptyKey.
|
|
const KeyT EmptyKey = getEmptyKey();
|
|
for (unsigned i = 0; i != InitBuckets; ++i)
|
|
new (&Buckets[i].first) KeyT(EmptyKey);
|
|
}
|
|
|
|
void grow(unsigned AtLeast) {
|
|
unsigned OldNumBuckets = NumBuckets;
|
|
BucketT *OldBuckets = Buckets;
|
|
|
|
// Double the number of buckets.
|
|
while (NumBuckets <= AtLeast)
|
|
NumBuckets <<= 1;
|
|
NumTombstones = 0;
|
|
Buckets = static_cast<BucketT*>(operator new(sizeof(BucketT)*NumBuckets));
|
|
|
|
// Initialize all the keys to EmptyKey.
|
|
const KeyT EmptyKey = getEmptyKey();
|
|
for (unsigned i = 0, e = NumBuckets; i != e; ++i)
|
|
new (&Buckets[i].first) KeyT(EmptyKey);
|
|
|
|
// Insert all the old elements.
|
|
const KeyT TombstoneKey = getTombstoneKey();
|
|
for (BucketT *B = OldBuckets, *E = OldBuckets+OldNumBuckets; B != E; ++B) {
|
|
if (!KeyInfoT::isEqual(B->first, EmptyKey) &&
|
|
!KeyInfoT::isEqual(B->first, TombstoneKey)) {
|
|
// Insert the key/value into the new table.
|
|
BucketT *DestBucket;
|
|
bool FoundVal = LookupBucketFor(B->first, DestBucket);
|
|
FoundVal = FoundVal; // silence warning.
|
|
assert(!FoundVal && "Key already in new map?");
|
|
DestBucket->first = B->first;
|
|
new (&DestBucket->second) ValueT(B->second);
|
|
|
|
// Free the value.
|
|
B->second.~ValueT();
|
|
}
|
|
B->first.~KeyT();
|
|
}
|
|
|
|
// Free the old table.
|
|
operator delete(OldBuckets);
|
|
}
|
|
|
|
void shrink_and_clear() {
|
|
unsigned OldNumBuckets = NumBuckets;
|
|
BucketT *OldBuckets = Buckets;
|
|
|
|
// Reduce the number of buckets.
|
|
NumBuckets = NumEntries > 32 ? 1 << (Log2_32_Ceil(NumEntries) + 1)
|
|
: 64;
|
|
NumTombstones = 0;
|
|
Buckets = static_cast<BucketT*>(operator new(sizeof(BucketT)*NumBuckets));
|
|
|
|
// Initialize all the keys to EmptyKey.
|
|
const KeyT EmptyKey = getEmptyKey();
|
|
for (unsigned i = 0, e = NumBuckets; i != e; ++i)
|
|
new (&Buckets[i].first) KeyT(EmptyKey);
|
|
|
|
// Free the old buckets.
|
|
const KeyT TombstoneKey = getTombstoneKey();
|
|
for (BucketT *B = OldBuckets, *E = OldBuckets+OldNumBuckets; B != E; ++B) {
|
|
if (!KeyInfoT::isEqual(B->first, EmptyKey) &&
|
|
!KeyInfoT::isEqual(B->first, TombstoneKey)) {
|
|
// Free the value.
|
|
B->second.~ValueT();
|
|
}
|
|
B->first.~KeyT();
|
|
}
|
|
|
|
// Free the old table.
|
|
operator delete(OldBuckets);
|
|
|
|
NumEntries = 0;
|
|
}
|
|
};
|
|
|
|
template<typename KeyT, typename ValueT, typename KeyInfoT, typename ValueInfoT>
|
|
class DenseMapIterator {
|
|
typedef std::pair<KeyT, ValueT> BucketT;
|
|
protected:
|
|
const BucketT *Ptr, *End;
|
|
public:
|
|
DenseMapIterator(const BucketT *Pos, const BucketT *E) : Ptr(Pos), End(E) {
|
|
AdvancePastEmptyBuckets();
|
|
}
|
|
|
|
std::pair<KeyT, ValueT> &operator*() const {
|
|
return *const_cast<BucketT*>(Ptr);
|
|
}
|
|
std::pair<KeyT, ValueT> *operator->() const {
|
|
return const_cast<BucketT*>(Ptr);
|
|
}
|
|
|
|
bool operator==(const DenseMapIterator &RHS) const {
|
|
return Ptr == RHS.Ptr;
|
|
}
|
|
bool operator!=(const DenseMapIterator &RHS) const {
|
|
return Ptr != RHS.Ptr;
|
|
}
|
|
|
|
inline DenseMapIterator& operator++() { // Preincrement
|
|
++Ptr;
|
|
AdvancePastEmptyBuckets();
|
|
return *this;
|
|
}
|
|
DenseMapIterator operator++(int) { // Postincrement
|
|
DenseMapIterator tmp = *this; ++*this; return tmp;
|
|
}
|
|
|
|
private:
|
|
void AdvancePastEmptyBuckets() {
|
|
const KeyT Empty = KeyInfoT::getEmptyKey();
|
|
const KeyT Tombstone = KeyInfoT::getTombstoneKey();
|
|
|
|
while (Ptr != End &&
|
|
(KeyInfoT::isEqual(Ptr->first, Empty) ||
|
|
KeyInfoT::isEqual(Ptr->first, Tombstone)))
|
|
++Ptr;
|
|
}
|
|
};
|
|
|
|
template<typename KeyT, typename ValueT, typename KeyInfoT, typename ValueInfoT>
|
|
class DenseMapConstIterator : public DenseMapIterator<KeyT, ValueT, KeyInfoT> {
|
|
public:
|
|
DenseMapConstIterator(const std::pair<KeyT, ValueT> *Pos,
|
|
const std::pair<KeyT, ValueT> *E)
|
|
: DenseMapIterator<KeyT, ValueT, KeyInfoT>(Pos, E) {
|
|
}
|
|
const std::pair<KeyT, ValueT> &operator*() const {
|
|
return *this->Ptr;
|
|
}
|
|
const std::pair<KeyT, ValueT> *operator->() const {
|
|
return this->Ptr;
|
|
}
|
|
};
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif
|