Squashed 'third_party/ntcore_2016/' content from commit d8de5e4
Change-Id: Id4839f41b6a620d8bae58dcf1710016671cc4992
git-subtree-dir: third_party/ntcore_2016
git-subtree-split: d8de5e4f19e612e7102172c0dbf152ce82d3d63a
diff --git a/src/llvm/SmallPtrSet.cpp b/src/llvm/SmallPtrSet.cpp
new file mode 100644
index 0000000..d23599a
--- /dev/null
+++ b/src/llvm/SmallPtrSet.cpp
@@ -0,0 +1,338 @@
+//===- llvm/ADT/SmallPtrSet.cpp - 'Normally small' pointer set ------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the SmallPtrSet class. See SmallPtrSet.h for an
+// overview of the algorithm.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/SmallPtrSet.h"
+#include "llvm/DenseMapInfo.h"
+#include "llvm/MathExtras.h"
+#include <algorithm>
+#include <cstdlib>
+
+using namespace llvm;
+
+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 (const void **APtr = SmallArray, **E = SmallArray+NumElements;
+ APtr != E; ++APtr)
+ if (*APtr == Ptr)
+ return std::make_pair(APtr, false);
+
+ // Nope, there isn't. If we stay small, just 'pushback' now.
+ if (NumElements < CurArraySize) {
+ SmallArray[NumElements++] = Ptr;
+ return std::make_pair(SmallArray + (NumElements - 1), true);
+ }
+ // Otherwise, hit the big set case, which will call 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.
+ 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 std::make_pair(Bucket, true);
+}
+
+bool SmallPtrSetImplBase::erase_imp(const void * Ptr) {
+ if (isSmall()) {
+ // Check to see if it is in the set.
+ for (const void **APtr = SmallArray, **E = SmallArray+NumElements;
+ APtr != E; ++APtr)
+ if (*APtr == Ptr) {
+ // If it is in the set, replace this element.
+ *APtr = E[-1];
+ E[-1] = getEmptyMarker();
+ --NumElements;
+ return true;
+ }
+
+ return false;
+ }
+
+ // Okay, we know we have space. Find a hash bucket.
+ void **Bucket = const_cast<void**>(FindBucketFor(Ptr));
+ if (*Bucket != Ptr) return false; // Not in the set?
+
+ // Set this as a tombstone.
+ *Bucket = getTombstoneMarker();
+ --NumElements;
+ ++NumTombstones;
+ return true;
+}
+
+const void * const *SmallPtrSetImplBase::FindBucketFor(const void *Ptr) const {
+ unsigned Bucket = DenseMapInfo<void *>::getHashValue(Ptr) & (CurArraySize-1);
+ unsigned ArraySize = CurArraySize;
+ unsigned ProbeAmt = 1;
+ const void *const *Array = CurArray;
+ const void *const *Tombstone = nullptr;
+ while (1) {
+ // 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 (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)
+ Tombstone = Array+Bucket; // Remember the first tombstone found.
+
+ // It's a hash collision or a tombstone. Reprobe.
+ Bucket = (Bucket + ProbeAmt++) & (ArraySize-1);
+ }
+}
+
+/// Grow - Allocate a larger backing store for the buckets and move it over.
+///
+void SmallPtrSetImplBase::Grow(unsigned NewSize) {
+ // Allocate at twice as many buckets, but at least 128.
+ unsigned OldSize = CurArraySize;
+
+ const void **OldBuckets = CurArray;
+ bool WasSmall = isSmall();
+
+ // Install the new array. Clear all the buckets to empty.
+ CurArray = (const void**)malloc(sizeof(void*) * NewSize);
+ assert(CurArray && "Failed to allocate memory?");
+ CurArraySize = NewSize;
+ memset(CurArray, -1, NewSize*sizeof(void*));
+
+ // Copy over all the elements.
+ if (WasSmall) {
+ // Small sets store their elements in order.
+ for (const void **BucketPtr = OldBuckets, **E = OldBuckets+NumElements;
+ BucketPtr != E; ++BucketPtr) {
+ const void *Elt = *BucketPtr;
+ *const_cast<void**>(FindBucketFor(Elt)) = const_cast<void*>(Elt);
+ }
+ } else {
+ // Copy over all valid entries.
+ for (const void **BucketPtr = OldBuckets, **E = OldBuckets+OldSize;
+ BucketPtr != E; ++BucketPtr) {
+ // Copy over the element if it is valid.
+ const void *Elt = *BucketPtr;
+ if (Elt != getTombstoneMarker() && Elt != getEmptyMarker())
+ *const_cast<void**>(FindBucketFor(Elt)) = const_cast<void*>(Elt);
+ }
+
+ free(OldBuckets);
+ 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()) {
+ CurArray = SmallArray;
+ // Otherwise, allocate new heap space (unless we were the same size)
+ } else {
+ CurArray = (const void**)malloc(sizeof(void*) * that.CurArraySize);
+ assert(CurArray && "Failed to allocate memory?");
+ }
+
+ // Copy over the new array size
+ CurArraySize = that.CurArraySize;
+
+ // 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 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;
+ // Otherwise, allocate new heap space (unless we were the same size)
+ } else if (CurArraySize != RHS.CurArraySize) {
+ if (isSmall())
+ 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?");
+ }
+
+ // Copy over the new array size
+ CurArraySize = RHS.CurArraySize;
+
+ // Copy over the contents from the other set
+ memcpy(CurArray, RHS.CurArray, sizeof(void*)*CurArraySize);
+
+ NumElements = RHS.NumElements;
+ NumTombstones = RHS.NumTombstones;
+}
+
+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);
+}