//
// The LLVM Compiler Infrastructure
//
-// This file was developed by James M. Laskey 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/FoldingSet.h"
-
-#include "llvm/ADT/MathExtras.h"
-
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include <cassert>
+#include <cstring>
using namespace llvm;
//===----------------------------------------------------------------------===//
-// FoldingSetImpl::NodeID Implementation
+// FoldingSetNodeID Implementation
/// Add* - Add various data types to Bit data.
///
-void FoldingSetImpl::NodeID::AddPointer(const void *Ptr) {
+void FoldingSetNodeID::AddPointer(const void *Ptr) {
// Note: this adds pointers to the hash using sizes and endianness that
// depend on the host. It doesn't matter however, because hashing on
// pointer values in inherently unstable. Nothing should depend on the
if (sizeof(intptr_t) > sizeof(unsigned))
Bits.push_back(unsigned(uint64_t(PtrI) >> 32));
}
-void FoldingSetImpl::NodeID::AddInteger(signed I) {
+void FoldingSetNodeID::AddInteger(signed I) {
Bits.push_back(I);
}
-void FoldingSetImpl::NodeID::AddInteger(unsigned I) {
+void FoldingSetNodeID::AddInteger(unsigned I) {
Bits.push_back(I);
}
-void FoldingSetImpl::NodeID::AddInteger(uint64_t I) {
- Bits.push_back(unsigned(I));
- Bits.push_back(unsigned(I >> 32));
+void FoldingSetNodeID::AddInteger(long I) {
+ AddInteger((unsigned long)I);
+}
+void FoldingSetNodeID::AddInteger(unsigned long I) {
+ if (sizeof(long) == sizeof(int))
+ AddInteger(unsigned(I));
+ else if (sizeof(long) == sizeof(long long)) {
+ AddInteger((unsigned long long)I);
+ } else {
+ LLVM_UNREACHABLE("unexpected sizeof(long)");
+ }
}
-void FoldingSetImpl::NodeID::AddFloat(float F) {
- Bits.push_back(FloatToBits(F));
+void FoldingSetNodeID::AddInteger(long long I) {
+ AddInteger((unsigned long long)I);
}
-void FoldingSetImpl::NodeID::AddDouble(double D) {
- Bits.push_back(DoubleToBits(D));
+void FoldingSetNodeID::AddInteger(unsigned long long I) {
+ AddInteger(unsigned(I));
+ if ((uint64_t)(int)I != I)
+ Bits.push_back(unsigned(I >> 32));
}
-void FoldingSetImpl::NodeID::AddString(const std::string &String) {
- // Note: An assumption is made here that strings are composed of one byte
- // chars.
- unsigned Size = String.size();
- unsigned Units = Size / sizeof(unsigned);
- const unsigned *Base = (const unsigned *)String.data();
- Bits.insert(Bits.end(), Base, Base + Units);
- if (Size & 3) {
- unsigned V = 0;
- for (unsigned i = Units * sizeof(unsigned); i < Size; ++i)
- V = (V << 8) | String[i];
- Bits.push_back(V);
+
+void FoldingSetNodeID::AddString(const char *String, const char *End) {
+ unsigned Size = static_cast<unsigned>(End - String);
+ Bits.push_back(Size);
+ if (!Size) return;
+
+ unsigned Units = Size / 4;
+ unsigned Pos = 0;
+ const unsigned *Base = (const unsigned *)String;
+
+ // If the string is aligned do a bulk transfer.
+ if (!((intptr_t)Base & 3)) {
+ Bits.append(Base, Base + Units);
+ Pos = (Units + 1) * 4;
+ } else {
+ // Otherwise do it the hard way.
+ for (Pos += 4; Pos <= Size; Pos += 4) {
+ unsigned V = ((unsigned char)String[Pos - 4] << 24) |
+ ((unsigned char)String[Pos - 3] << 16) |
+ ((unsigned char)String[Pos - 2] << 8) |
+ (unsigned char)String[Pos - 1];
+ Bits.push_back(V);
+ }
}
+
+ // With the leftover bits.
+ unsigned V = 0;
+ // Pos will have overshot size by 4 - #bytes left over.
+ switch (Pos - Size) {
+ case 1: V = (V << 8) | (unsigned char)String[Size - 3]; // Fall thru.
+ case 2: V = (V << 8) | (unsigned char)String[Size - 2]; // Fall thru.
+ case 3: V = (V << 8) | (unsigned char)String[Size - 1]; break;
+ default: return; // Nothing left.
+ }
+
+ Bits.push_back(V);
+}
+
+void FoldingSetNodeID::AddString(const char *String) {
+ AddString(String, String + strlen(String));
+}
+
+void FoldingSetNodeID::AddString(const std::string &String) {
+ AddString(&*String.begin(), &*String.end());
}
-/// ComputeHash - Compute a strong hash value for this NodeID, used to
+/// ComputeHash - Compute a strong hash value for this FoldingSetNodeID, used to
/// lookup the node in the FoldingSetImpl.
-unsigned FoldingSetImpl::NodeID::ComputeHash() const {
+unsigned FoldingSetNodeID::ComputeHash() const {
// This is adapted from SuperFastHash by Paul Hsieh.
- unsigned Hash = Bits.size();
+ unsigned Hash = static_cast<unsigned>(Bits.size());
for (const unsigned *BP = &Bits[0], *E = BP+Bits.size(); BP != E; ++BP) {
unsigned Data = *BP;
Hash += Data & 0xFFFF;
/// operator== - Used to compare two nodes to each other.
///
-bool FoldingSetImpl::NodeID::operator==(const FoldingSetImpl::NodeID &RHS)const{
+bool FoldingSetNodeID::operator==(const FoldingSetNodeID &RHS)const{
if (Bits.size() != RHS.Bits.size()) return false;
return memcmp(&Bits[0], &RHS.Bits[0], Bits.size()*sizeof(Bits[0])) == 0;
}
//===----------------------------------------------------------------------===//
-// FoldingSetImpl Implementation
-
-FoldingSetImpl::FoldingSetImpl() : NumNodes(0) {
- NumBuckets = 64;
- Buckets = new void*[NumBuckets];
- memset(Buckets, 0, NumBuckets*sizeof(void*));
-}
-FoldingSetImpl::~FoldingSetImpl() {
- delete [] Buckets;
-}
+/// Helper functions for FoldingSetImpl.
/// GetNextPtr - In order to save space, each bucket is a
/// singly-linked-list. In order to make deletion more efficient, we make
/// the list circular, so we can delete a node without computing its hash.
/// The problem with this is that the start of the hash buckets are not
-/// Nodes. If NextInBucketPtr is a bucket pointer, this method returns null
-/// : use GetBucketPtr when this happens.
-FoldingSetImpl::Node *FoldingSetImpl::GetNextPtr(void *NextInBucketPtr) {
- if (NextInBucketPtr >= Buckets && NextInBucketPtr < Buckets+NumBuckets)
+/// Nodes. If NextInBucketPtr is a bucket pointer, this method returns null:
+/// use GetBucketPtr when this happens.
+static FoldingSetImpl::Node *GetNextPtr(void *NextInBucketPtr) {
+ // The low bit is set if this is the pointer back to the bucket.
+ if (reinterpret_cast<intptr_t>(NextInBucketPtr) & 1)
return 0;
- return static_cast<Node*>(NextInBucketPtr);
+
+ return static_cast<FoldingSetImpl::Node*>(NextInBucketPtr);
}
-/// GetNextPtr - This is just like the previous GetNextPtr implementation,
-/// but allows a bucket array to be specified.
-FoldingSetImpl::Node *FoldingSetImpl::GetNextPtr(void *NextInBucketPtr,
- void **Bucks,
- unsigned NumBuck) {
- if (NextInBucketPtr >= Bucks && NextInBucketPtr < Bucks+NumBuck)
- return 0;
- return static_cast<Node*>(NextInBucketPtr);
-}
-/// GetBucketPtr - Provides a casting of a bucket pointer for isNode
/// testing.
-void **FoldingSetImpl::GetBucketPtr(void *NextInBucketPtr) {
- return static_cast<void**>(NextInBucketPtr);
+static void **GetBucketPtr(void *NextInBucketPtr) {
+ intptr_t Ptr = reinterpret_cast<intptr_t>(NextInBucketPtr);
+ assert((Ptr & 1) && "Not a bucket pointer");
+ return reinterpret_cast<void**>(Ptr & ~intptr_t(1));
}
/// GetBucketFor - Hash the specified node ID and return the hash bucket for
/// the specified ID.
-void **FoldingSetImpl::GetBucketFor(const NodeID &ID) const {
+static void **GetBucketFor(const FoldingSetNodeID &ID,
+ void **Buckets, unsigned NumBuckets) {
// NumBuckets is always a power of 2.
unsigned BucketNum = ID.ComputeHash() & (NumBuckets-1);
- return Buckets+BucketNum;
+ return Buckets + BucketNum;
+}
+
+//===----------------------------------------------------------------------===//
+// FoldingSetImpl Implementation
+
+FoldingSetImpl::FoldingSetImpl(unsigned Log2InitSize) {
+ assert(5 < Log2InitSize && Log2InitSize < 32 &&
+ "Initial hash table size out of range");
+ NumBuckets = 1 << Log2InitSize;
+ Buckets = new void*[NumBuckets+1];
+ clear();
+}
+FoldingSetImpl::~FoldingSetImpl() {
+ delete [] Buckets;
+}
+void FoldingSetImpl::clear() {
+ // Set all but the last bucket to null pointers.
+ memset(Buckets, 0, NumBuckets*sizeof(void*));
+
+ // Set the very last bucket to be a non-null "pointer".
+ Buckets[NumBuckets] = reinterpret_cast<void*>(-1);
+
+ // Reset the node count to zero.
+ NumNodes = 0;
}
/// GrowHashTable - Double the size of the hash table and rehash everything.
unsigned OldNumBuckets = NumBuckets;
NumBuckets <<= 1;
- // Reset the node count to zero: we're going to reinsert everything.
- NumNodes = 0;
-
// Clear out new buckets.
- Buckets = new void*[NumBuckets];
- memset(Buckets, 0, NumBuckets*sizeof(void*));
+ Buckets = new void*[NumBuckets+1];
+ clear();
// Walk the old buckets, rehashing nodes into their new place.
+ FoldingSetNodeID ID;
for (unsigned i = 0; i != OldNumBuckets; ++i) {
void *Probe = OldBuckets[i];
if (!Probe) continue;
- while (Node *NodeInBucket = GetNextPtr(Probe, OldBuckets, OldNumBuckets)){
+ while (Node *NodeInBucket = GetNextPtr(Probe)) {
// Figure out the next link, remove NodeInBucket from the old link.
Probe = NodeInBucket->getNextInBucket();
NodeInBucket->SetNextInBucket(0);
// Insert the node into the new bucket, after recomputing the hash.
- NodeID ID;
GetNodeProfile(ID, NodeInBucket);
- InsertNode(NodeInBucket, GetBucketFor(ID));
+ InsertNode(NodeInBucket, GetBucketFor(ID, Buckets, NumBuckets));
+ ID.clear();
}
}
/// FindNodeOrInsertPos - Look up the node specified by ID. If it exists,
/// return it. If not, return the insertion token that will make insertion
/// faster.
-FoldingSetImpl::Node *FoldingSetImpl::FindNodeOrInsertPos(const NodeID &ID,
- void *&InsertPos) {
- void **Bucket = GetBucketFor(ID);
+FoldingSetImpl::Node
+*FoldingSetImpl::FindNodeOrInsertPos(const FoldingSetNodeID &ID,
+ void *&InsertPos) {
+
+ void **Bucket = GetBucketFor(ID, Buckets, NumBuckets);
void *Probe = *Bucket;
InsertPos = 0;
+ FoldingSetNodeID OtherID;
while (Node *NodeInBucket = GetNextPtr(Probe)) {
- NodeID OtherID;
GetNodeProfile(OtherID, NodeInBucket);
if (OtherID == ID)
return NodeInBucket;
Probe = NodeInBucket->getNextInBucket();
+ OtherID.clear();
}
// Didn't find the node, return null with the bucket as the InsertPos.
/// is not already in the map. InsertPos must be obtained from
/// FindNodeOrInsertPos.
void FoldingSetImpl::InsertNode(Node *N, void *InsertPos) {
- ++NumNodes;
+ assert(N->getNextInBucket() == 0);
// Do we need to grow the hashtable?
- if (NumNodes > NumBuckets*2) {
+ if (NumNodes+1 > NumBuckets*2) {
GrowHashTable();
- NodeID ID;
+ FoldingSetNodeID ID;
GetNodeProfile(ID, N);
- InsertPos = GetBucketFor(ID);
+ InsertPos = GetBucketFor(ID, Buckets, NumBuckets);
}
+
+ ++NumNodes;
/// The insert position is actually a bucket pointer.
void **Bucket = static_cast<void**>(InsertPos);
void *Next = *Bucket;
// If this is the first insertion into this bucket, its next pointer will be
- // null. Pretend as if it pointed to itself.
+ // null. Pretend as if it pointed to itself, setting the low bit to indicate
+ // that it is a pointer to the bucket.
if (Next == 0)
- Next = Bucket;
+ Next = reinterpret_cast<void*>(reinterpret_cast<intptr_t>(Bucket)|1);
- // Set the nodes next pointer, and make the bucket point to the node.
+ // Set the node's next pointer, and make the bucket point to the node.
N->SetNextInBucket(Next);
*Bucket = N;
}
/// removed or false if the node was not in the folding set.
bool FoldingSetImpl::RemoveNode(Node *N) {
// Because each bucket is a circular list, we don't need to compute N's hash
- // to remove it. Chase around the list until we find the node (or bucket)
- // which points to N.
+ // to remove it.
void *Ptr = N->getNextInBucket();
if (Ptr == 0) return false; // Not in folding set.
--NumNodes;
+ N->SetNextInBucket(0);
+ // Remember what N originally pointed to, either a bucket or another node.
void *NodeNextPtr = Ptr;
- N->SetNextInBucket(0);
+
+ // Chase around the list until we find the node (or bucket) which points to N.
while (true) {
if (Node *NodeInBucket = GetNextPtr(Ptr)) {
// Advance pointer.
/// equal to the specified node, return it. Otherwise, insert 'N' and it
/// instead.
FoldingSetImpl::Node *FoldingSetImpl::GetOrInsertNode(FoldingSetImpl::Node *N) {
- NodeID ID;
+ FoldingSetNodeID ID;
GetNodeProfile(ID, N);
void *IP;
if (Node *E = FindNodeOrInsertPos(ID, IP))
InsertNode(N, IP);
return N;
}
+
+//===----------------------------------------------------------------------===//
+// FoldingSetIteratorImpl Implementation
+
+FoldingSetIteratorImpl::FoldingSetIteratorImpl(void **Bucket) {
+ // Skip to the first non-null non-self-cycle bucket.
+ while (*Bucket != reinterpret_cast<void*>(-1) &&
+ (*Bucket == 0 || GetNextPtr(*Bucket) == 0))
+ ++Bucket;
+
+ NodePtr = static_cast<FoldingSetNode*>(*Bucket);
+}
+
+void FoldingSetIteratorImpl::advance() {
+ // If there is another link within this bucket, go to it.
+ void *Probe = NodePtr->getNextInBucket();
+
+ if (FoldingSetNode *NextNodeInBucket = GetNextPtr(Probe))
+ NodePtr = NextNodeInBucket;
+ else {
+ // Otherwise, this is the last link in this bucket.
+ void **Bucket = GetBucketPtr(Probe);
+
+ // Skip to the next non-null non-self-cycle bucket.
+ do {
+ ++Bucket;
+ } while (*Bucket != reinterpret_cast<void*>(-1) &&
+ (*Bucket == 0 || GetNextPtr(*Bucket) == 0));
+
+ NodePtr = static_cast<FoldingSetNode*>(*Bucket);
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// FoldingSetBucketIteratorImpl Implementation
+
+FoldingSetBucketIteratorImpl::FoldingSetBucketIteratorImpl(void **Bucket) {
+ Ptr = (*Bucket == 0 || GetNextPtr(*Bucket) == 0) ? (void*) Bucket : *Bucket;
+}