//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Chris Lattner and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/DenseMapInfo.h"
#include "llvm/Support/MathExtras.h"
+#include <algorithm>
#include <cstdlib>
using namespace llvm;
-bool SmallPtrSetImpl::insert(void *Ptr) {
+void SmallPtrSetImplBase::shrink_and_clear() {
+ assert(!isSmall() && "Can't shrink a small set!");
+ free(CurArray);
+
+ // Reduce the number of buckets.
+ CurArraySize = NumElements > 16 ? 1 << (Log2_32_Ceil(NumElements) + 1) : 32;
+ NumElements = NumTombstones = 0;
+
+ // Install the new array. Clear all the buckets to empty.
+ CurArray = (const void**)malloc(sizeof(void*) * CurArraySize);
+ assert(CurArray && "Failed to allocate memory?");
+ memset(CurArray, -1, CurArraySize*sizeof(void*));
+}
+
+std::pair<const void *const *, bool>
+SmallPtrSetImplBase::insert_imp(const void *Ptr) {
if (isSmall()) {
// Check to see if it is already in the set.
- for (void **APtr = SmallArray, **E = SmallArray+NumElements;
+ for (const void **APtr = SmallArray, **E = SmallArray+NumElements;
APtr != E; ++APtr)
if (*APtr == Ptr)
- return false;
-
+ return std::make_pair(APtr, false);
+
// Nope, there isn't. If we stay small, just 'pushback' now.
- if (NumElements < CurArraySize-1) {
+ if (NumElements < CurArraySize) {
SmallArray[NumElements++] = Ptr;
- return true;
+ return std::make_pair(SmallArray + (NumElements - 1), true);
}
// Otherwise, hit the big set case, which will call grow.
}
-
- // If more than 3/4 of the array is full, grow.
- if (NumElements*4 >= CurArraySize*3 ||
- CurArraySize-(NumElements+NumTombstones) < CurArraySize/8)
- Grow();
+
+ if (LLVM_UNLIKELY(NumElements * 4 >= CurArraySize * 3)) {
+ // If more than 3/4 of the array is full, grow.
+ Grow(CurArraySize < 64 ? 128 : CurArraySize*2);
+ } else if (LLVM_UNLIKELY(CurArraySize - (NumElements + NumTombstones) <
+ CurArraySize / 8)) {
+ // If fewer of 1/8 of the array is empty (meaning that many are filled with
+ // tombstones), rehash.
+ Grow(CurArraySize);
+ }
// Okay, we know we have space. Find a hash bucket.
- void **Bucket = const_cast<void**>(FindBucketFor(Ptr));
- if (*Bucket == Ptr) return false; // Already inserted, good.
-
+ const void **Bucket = const_cast<const void**>(FindBucketFor(Ptr));
+ if (*Bucket == Ptr)
+ return std::make_pair(Bucket, false); // Already inserted, good.
+
// Otherwise, insert it!
if (*Bucket == getTombstoneMarker())
--NumTombstones;
*Bucket = Ptr;
++NumElements; // Track density.
- return true;
+ return std::make_pair(Bucket, true);
}
-bool SmallPtrSetImpl::erase(void *Ptr) {
+bool SmallPtrSetImplBase::erase_imp(const void * Ptr) {
if (isSmall()) {
// Check to see if it is in the set.
- for (void **APtr = SmallArray, **E = SmallArray+NumElements;
+ for (const void **APtr = SmallArray, **E = SmallArray+NumElements;
APtr != E; ++APtr)
if (*APtr == Ptr) {
// If it is in the set, replace this element.
return true;
}
-void * const *SmallPtrSetImpl::FindBucketFor(void *Ptr) const {
- unsigned Bucket = Hash(Ptr);
+const void * const *SmallPtrSetImplBase::FindBucketFor(const void *Ptr) const {
+ unsigned Bucket = DenseMapInfo<void *>::getHashValue(Ptr) & (CurArraySize-1);
unsigned ArraySize = CurArraySize;
unsigned ProbeAmt = 1;
- void *const *Array = CurArray;
- void *const *Tombstone = 0;
+ const void *const *Array = CurArray;
+ const void *const *Tombstone = nullptr;
while (1) {
- // Found Ptr's bucket?
- if (Array[Bucket] == Ptr)
- return Array+Bucket;
-
// If we found an empty bucket, the pointer doesn't exist in the set.
// Return a tombstone if we've seen one so far, or the empty bucket if
// not.
- if (Array[Bucket] == getEmptyMarker())
+ if (LLVM_LIKELY(Array[Bucket] == getEmptyMarker()))
return Tombstone ? Tombstone : Array+Bucket;
-
+
+ // Found Ptr's bucket?
+ if (LLVM_LIKELY(Array[Bucket] == Ptr))
+ return Array+Bucket;
+
// If this is a tombstone, remember it. If Ptr ends up not in the set, we
// prefer to return it than something that would require more probing.
if (Array[Bucket] == getTombstoneMarker() && !Tombstone)
/// Grow - Allocate a larger backing store for the buckets and move it over.
///
-void SmallPtrSetImpl::Grow() {
+void SmallPtrSetImplBase::Grow(unsigned NewSize) {
// Allocate at twice as many buckets, but at least 128.
unsigned OldSize = CurArraySize;
- unsigned NewSize = OldSize < 64 ? 128 : OldSize*2;
- void **OldBuckets = CurArray;
+ const void **OldBuckets = CurArray;
bool WasSmall = isSmall();
// Install the new array. Clear all the buckets to empty.
- CurArray = (void**)malloc(sizeof(void*) * (NewSize+1));
+ CurArray = (const void**)malloc(sizeof(void*) * NewSize);
assert(CurArray && "Failed to allocate memory?");
CurArraySize = NewSize;
memset(CurArray, -1, NewSize*sizeof(void*));
- // The end pointer, always valid, is set to a valid element to help the
- // iterator.
- CurArray[NewSize] = 0;
-
// Copy over all the elements.
if (WasSmall) {
// Small sets store their elements in order.
- for (void **BucketPtr = OldBuckets, **E = OldBuckets+NumElements;
+ for (const void **BucketPtr = OldBuckets, **E = OldBuckets+NumElements;
BucketPtr != E; ++BucketPtr) {
- void *Elt = *BucketPtr;
- *const_cast<void**>(FindBucketFor(Elt)) = Elt;
+ const void *Elt = *BucketPtr;
+ *const_cast<void**>(FindBucketFor(Elt)) = const_cast<void*>(Elt);
}
} else {
// Copy over all valid entries.
- for (void **BucketPtr = OldBuckets, **E = OldBuckets+OldSize;
+ for (const void **BucketPtr = OldBuckets, **E = OldBuckets+OldSize;
BucketPtr != E; ++BucketPtr) {
// Copy over the element if it is valid.
- void *Elt = *BucketPtr;
+ const void *Elt = *BucketPtr;
if (Elt != getTombstoneMarker() && Elt != getEmptyMarker())
- *const_cast<void**>(FindBucketFor(Elt)) = Elt;
+ *const_cast<void**>(FindBucketFor(Elt)) = const_cast<void*>(Elt);
}
free(OldBuckets);
}
}
-SmallPtrSetImpl::SmallPtrSetImpl(const SmallPtrSetImpl& that) {
- NumElements = that.NumElements;
- NumTombstones = 0;
+SmallPtrSetImplBase::SmallPtrSetImplBase(const void **SmallStorage,
+ const SmallPtrSetImplBase& that) {
+ SmallArray = SmallStorage;
+
+ // If we're becoming small, prepare to insert into our stack space
if (that.isSmall()) {
- CurArraySize = that.CurArraySize;
- CurArray = &SmallArray[0];
- // Copy the entire contents of the array, including the -1's and the null
- // terminator.
- memcpy(CurArray, that.CurArray, sizeof(void*)*(CurArraySize+1));
+ CurArray = SmallArray;
+ // Otherwise, allocate new heap space (unless we were the same size)
} else {
- CurArraySize = that.NumElements < 64 ? 128 : that.CurArraySize*2;
- CurArray = (void**)malloc(sizeof(void*) * (CurArraySize+1));
+ CurArray = (const void**)malloc(sizeof(void*) * that.CurArraySize);
assert(CurArray && "Failed to allocate memory?");
- memset(CurArray, -1, CurArraySize*sizeof(void*));
-
- // The end pointer, always valid, is set to a valid element to help the
- // iterator.
- CurArray[CurArraySize] = 0;
+ }
+
+ // Copy over the new array size
+ CurArraySize = that.CurArraySize;
- // Copy over all valid entries.
- for (void **BucketPtr = that.CurArray, **E = that.CurArray+that.CurArraySize;
- BucketPtr != E; ++BucketPtr) {
- // Copy over the element if it is valid.
- void *Elt = *BucketPtr;
- if (Elt != getTombstoneMarker() && Elt != getEmptyMarker())
- *const_cast<void**>(FindBucketFor(Elt)) = Elt;
- }
+ // Copy over the contents from the other set
+ memcpy(CurArray, that.CurArray, sizeof(void*)*CurArraySize);
+
+ NumElements = that.NumElements;
+ NumTombstones = that.NumTombstones;
+}
+
+SmallPtrSetImplBase::SmallPtrSetImplBase(const void **SmallStorage,
+ unsigned SmallSize,
+ SmallPtrSetImplBase &&that) {
+ SmallArray = SmallStorage;
+
+ // Copy over the basic members.
+ CurArraySize = that.CurArraySize;
+ NumElements = that.NumElements;
+ NumTombstones = that.NumTombstones;
+
+ // When small, just copy into our small buffer.
+ if (that.isSmall()) {
+ CurArray = SmallArray;
+ memcpy(CurArray, that.CurArray, sizeof(void *) * CurArraySize);
+ } else {
+ // Otherwise, we steal the large memory allocation and no copy is needed.
+ CurArray = that.CurArray;
+ that.CurArray = that.SmallArray;
}
+
+ // Make the "that" object small and empty.
+ that.CurArraySize = SmallSize;
+ assert(that.CurArray == that.SmallArray);
+ that.NumElements = 0;
+ that.NumTombstones = 0;
}
/// CopyFrom - implement operator= from a smallptrset that has the same pointer
/// type, but may have a different small size.
-void SmallPtrSetImpl::CopyFrom(const SmallPtrSetImpl &RHS) {
+void SmallPtrSetImplBase::CopyFrom(const SmallPtrSetImplBase &RHS) {
+ assert(&RHS != this && "Self-copy should be handled by the caller.");
+
if (isSmall() && RHS.isSmall())
assert(CurArraySize == RHS.CurArraySize &&
"Cannot assign sets with different small sizes");
-
+
// If we're becoming small, prepare to insert into our stack space
if (RHS.isSmall()) {
if (!isSmall())
free(CurArray);
- CurArray = &SmallArray[0];
+ CurArray = SmallArray;
// Otherwise, allocate new heap space (unless we were the same size)
} else if (CurArraySize != RHS.CurArraySize) {
if (isSmall())
- CurArray = (void**)malloc(sizeof(void*) * (RHS.CurArraySize+1));
- else
- CurArray = (void**)realloc(CurArray, sizeof(void*)*(RHS.CurArraySize+1));
+ CurArray = (const void**)malloc(sizeof(void*) * RHS.CurArraySize);
+ else {
+ const void **T = (const void**)realloc(CurArray,
+ sizeof(void*) * RHS.CurArraySize);
+ if (!T)
+ free(CurArray);
+ CurArray = T;
+ }
assert(CurArray && "Failed to allocate memory?");
}
CurArraySize = RHS.CurArraySize;
// Copy over the contents from the other set
- memcpy(CurArray, RHS.CurArray, sizeof(void*)*(CurArraySize+1));
+ memcpy(CurArray, RHS.CurArray, sizeof(void*)*CurArraySize);
NumElements = RHS.NumElements;
NumTombstones = RHS.NumTombstones;
}
-SmallPtrSetImpl::~SmallPtrSetImpl() {
+void SmallPtrSetImplBase::MoveFrom(unsigned SmallSize,
+ SmallPtrSetImplBase &&RHS) {
+ assert(&RHS != this && "Self-move should be handled by the caller.");
+
+ if (!isSmall())
+ free(CurArray);
+
+ if (RHS.isSmall()) {
+ // Copy a small RHS rather than moving.
+ CurArray = SmallArray;
+ memcpy(CurArray, RHS.CurArray, sizeof(void*)*RHS.CurArraySize);
+ } else {
+ CurArray = RHS.CurArray;
+ RHS.CurArray = RHS.SmallArray;
+ }
+
+ // Copy the rest of the trivial members.
+ CurArraySize = RHS.CurArraySize;
+ NumElements = RHS.NumElements;
+ NumTombstones = RHS.NumTombstones;
+
+ // Make the RHS small and empty.
+ RHS.CurArraySize = SmallSize;
+ assert(RHS.CurArray == RHS.SmallArray);
+ RHS.NumElements = 0;
+ RHS.NumTombstones = 0;
+}
+
+void SmallPtrSetImplBase::swap(SmallPtrSetImplBase &RHS) {
+ if (this == &RHS) return;
+
+ // We can only avoid copying elements if neither set is small.
+ if (!this->isSmall() && !RHS.isSmall()) {
+ std::swap(this->CurArray, RHS.CurArray);
+ std::swap(this->CurArraySize, RHS.CurArraySize);
+ std::swap(this->NumElements, RHS.NumElements);
+ std::swap(this->NumTombstones, RHS.NumTombstones);
+ return;
+ }
+
+ // FIXME: From here on we assume that both sets have the same small size.
+
+ // If only RHS is small, copy the small elements into LHS and move the pointer
+ // from LHS to RHS.
+ if (!this->isSmall() && RHS.isSmall()) {
+ std::copy(RHS.SmallArray, RHS.SmallArray+RHS.CurArraySize,
+ this->SmallArray);
+ std::swap(this->NumElements, RHS.NumElements);
+ std::swap(this->CurArraySize, RHS.CurArraySize);
+ RHS.CurArray = this->CurArray;
+ RHS.NumTombstones = this->NumTombstones;
+ this->CurArray = this->SmallArray;
+ this->NumTombstones = 0;
+ return;
+ }
+
+ // If only LHS is small, copy the small elements into RHS and move the pointer
+ // from RHS to LHS.
+ if (this->isSmall() && !RHS.isSmall()) {
+ std::copy(this->SmallArray, this->SmallArray+this->CurArraySize,
+ RHS.SmallArray);
+ std::swap(RHS.NumElements, this->NumElements);
+ std::swap(RHS.CurArraySize, this->CurArraySize);
+ this->CurArray = RHS.CurArray;
+ this->NumTombstones = RHS.NumTombstones;
+ RHS.CurArray = RHS.SmallArray;
+ RHS.NumTombstones = 0;
+ return;
+ }
+
+ // Both a small, just swap the small elements.
+ assert(this->isSmall() && RHS.isSmall());
+ assert(this->CurArraySize == RHS.CurArraySize);
+ std::swap_ranges(this->SmallArray, this->SmallArray+this->CurArraySize,
+ RHS.SmallArray);
+ std::swap(this->NumElements, RHS.NumElements);
+}
+
+SmallPtrSetImplBase::~SmallPtrSetImplBase() {
if (!isSmall())
free(CurArray);
}