X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FFoldingSet.cpp;h=463511408759ccc8cb5829ecf19ce8103ce1028c;hb=78832c6e7d33094c6ef9e99b07dac6f60c0a1207;hp=c1b6511a9306565be362aa7103c2fee4919b386a;hpb=6616f7e2f147c2320973993cbfb241a82262b764;p=oota-llvm.git diff --git a/lib/Support/FoldingSet.cpp b/lib/Support/FoldingSet.cpp index c1b6511a930..46351140875 100644 --- a/lib/Support/FoldingSet.cpp +++ b/lib/Support/FoldingSet.cpp @@ -8,20 +8,42 @@ //===----------------------------------------------------------------------===// // // This file implements a hash set that can be used to remove duplication of -// nodes in a graph. This code was originally created by Chris Lattner for use -// with SelectionDAGCSEMap, but was isolated to provide use across the llvm code -// set. +// nodes in a graph. // //===----------------------------------------------------------------------===// #include "llvm/ADT/FoldingSet.h" +#include "llvm/ADT/Hashing.h" #include "llvm/Support/Allocator.h" #include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/Host.h" #include "llvm/Support/MathExtras.h" #include #include using namespace llvm; +//===----------------------------------------------------------------------===// +// FoldingSetNodeIDRef Implementation + +/// ComputeHash - Compute a strong hash value for this FoldingSetNodeIDRef, +/// used to lookup the node in the FoldingSetImpl. +unsigned FoldingSetNodeIDRef::ComputeHash() const { + return static_cast(hash_combine_range(Data, Data+Size)); +} + +bool FoldingSetNodeIDRef::operator==(FoldingSetNodeIDRef RHS) const { + if (Size != RHS.Size) return false; + return memcmp(Data, RHS.Data, Size*sizeof(*Data)) == 0; +} + +/// Used to compare the "ordering" of two nodes as defined by the +/// profiled bits and their ordering defined by memcmp(). +bool FoldingSetNodeIDRef::operator<(FoldingSetNodeIDRef RHS) const { + if (Size != RHS.Size) + return Size < RHS.Size; + return memcmp(Data, RHS.Data, Size*sizeof(*Data)) < 0; +} + //===----------------------------------------------------------------------===// // FoldingSetNodeID Implementation @@ -32,10 +54,8 @@ void FoldingSetNodeID::AddPointer(const void *Ptr) { // depend on the host. It doesn't matter however, because hashing on // pointer values in inherently unstable. Nothing should depend on the // ordering of nodes in the folding set. - intptr_t PtrI = (intptr_t)Ptr; - Bits.push_back(unsigned(PtrI)); - if (sizeof(intptr_t) > sizeof(unsigned)) - Bits.push_back(unsigned(uint64_t(PtrI) >> 32)); + Bits.append(reinterpret_cast(&Ptr), + reinterpret_cast(&Ptr+1)); } void FoldingSetNodeID::AddInteger(signed I) { Bits.push_back(I); @@ -60,7 +80,7 @@ void FoldingSetNodeID::AddInteger(long long I) { } void FoldingSetNodeID::AddInteger(unsigned long long I) { AddInteger(unsigned(I)); - if ((uint64_t)(int)I != I) + if ((uint64_t)(unsigned)I != I) Bits.push_back(unsigned(I >> 32)); } @@ -79,18 +99,32 @@ void FoldingSetNodeID::AddString(StringRef String) { 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); + // To be compatible with above bulk transfer, we need to take endianness + // into account. + if (sys::IsBigEndianHost) { + 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); + } + } else { + assert(sys::IsLittleEndianHost && "Unexpected host endianness"); + for (Pos += 4; Pos <= Size; Pos += 4) { + unsigned V = ((unsigned char)String[Pos - 1] << 24) | + ((unsigned char)String[Pos - 2] << 16) | + ((unsigned char)String[Pos - 3] << 8) | + (unsigned char)String[Pos - 4]; + Bits.push_back(V); + } } } // With the leftover bits. unsigned V = 0; - // Pos will have overshot size by 4 - #bytes left over. + // Pos will have overshot size by 4 - #bytes left over. + // No need to take endianness into account here - this is always executed. 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. @@ -101,34 +135,37 @@ void FoldingSetNodeID::AddString(StringRef String) { Bits.push_back(V); } +// AddNodeID - Adds the Bit data of another ID to *this. +void FoldingSetNodeID::AddNodeID(const FoldingSetNodeID &ID) { + Bits.append(ID.Bits.begin(), ID.Bits.end()); +} + /// ComputeHash - Compute a strong hash value for this FoldingSetNodeID, used to /// lookup the node in the FoldingSetImpl. unsigned FoldingSetNodeID::ComputeHash() const { - // This is adapted from SuperFastHash by Paul Hsieh. - unsigned Hash = static_cast(Bits.size()); - for (const unsigned *BP = &Bits[0], *E = BP+Bits.size(); BP != E; ++BP) { - unsigned Data = *BP; - Hash += Data & 0xFFFF; - unsigned Tmp = ((Data >> 16) << 11) ^ Hash; - Hash = (Hash << 16) ^ Tmp; - Hash += Hash >> 11; - } - - // Force "avalanching" of final 127 bits. - Hash ^= Hash << 3; - Hash += Hash >> 5; - Hash ^= Hash << 4; - Hash += Hash >> 17; - Hash ^= Hash << 25; - Hash += Hash >> 6; - return Hash; + return FoldingSetNodeIDRef(Bits.data(), Bits.size()).ComputeHash(); +} + +/// operator== - Used to compare two nodes to each other. +/// +bool FoldingSetNodeID::operator==(const FoldingSetNodeID &RHS) const { + return *this == FoldingSetNodeIDRef(RHS.Bits.data(), RHS.Bits.size()); } /// operator== - Used to compare two nodes to each other. /// -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; +bool FoldingSetNodeID::operator==(FoldingSetNodeIDRef RHS) const { + return FoldingSetNodeIDRef(Bits.data(), Bits.size()) == RHS; +} + +/// Used to compare the "ordering" of two nodes as defined by the +/// profiled bits and their ordering defined by memcmp(). +bool FoldingSetNodeID::operator<(const FoldingSetNodeID &RHS) const { + return *this < FoldingSetNodeIDRef(RHS.Bits.data(), RHS.Bits.size()); +} + +bool FoldingSetNodeID::operator<(FoldingSetNodeIDRef RHS) const { + return FoldingSetNodeIDRef(Bits.data(), Bits.size()) < RHS; } /// Intern - Copy this node's data to a memory region allocated from the @@ -153,7 +190,7 @@ FoldingSetNodeID::Intern(BumpPtrAllocator &Allocator) const { static FoldingSetImpl::Node *GetNextPtr(void *NextInBucketPtr) { // The low bit is set if this is the pointer back to the bucket. if (reinterpret_cast(NextInBucketPtr) & 1) - return 0; + return nullptr; return static_cast(NextInBucketPtr); } @@ -168,10 +205,9 @@ static void **GetBucketPtr(void *NextInBucketPtr) { /// GetBucketFor - Hash the specified node ID and return the hash bucket for /// the specified ID. -static void **GetBucketFor(const FoldingSetNodeID &ID, - void **Buckets, unsigned NumBuckets) { +static void **GetBucketFor(unsigned Hash, void **Buckets, unsigned NumBuckets) { // NumBuckets is always a power of 2. - unsigned BucketNum = ID.ComputeHash() & (NumBuckets-1); + unsigned BucketNum = Hash & (NumBuckets-1); return Buckets + BucketNum; } @@ -219,19 +255,20 @@ void FoldingSetImpl::GrowHashTable() { NumNodes = 0; // Walk the old buckets, rehashing nodes into their new place. - FoldingSetNodeID ID; + FoldingSetNodeID TempID; for (unsigned i = 0; i != OldNumBuckets; ++i) { void *Probe = OldBuckets[i]; if (!Probe) continue; while (Node *NodeInBucket = GetNextPtr(Probe)) { // Figure out the next link, remove NodeInBucket from the old link. Probe = NodeInBucket->getNextInBucket(); - NodeInBucket->SetNextInBucket(0); + NodeInBucket->SetNextInBucket(nullptr); // Insert the node into the new bucket, after recomputing the hash. - GetNodeProfile(NodeInBucket, ID); - InsertNode(NodeInBucket, GetBucketFor(ID, Buckets, NumBuckets)); - ID.clear(); + InsertNode(NodeInBucket, + GetBucketFor(ComputeNodeHash(NodeInBucket, TempID), + Buckets, NumBuckets)); + TempID.clear(); } } @@ -244,38 +281,36 @@ void FoldingSetImpl::GrowHashTable() { FoldingSetImpl::Node *FoldingSetImpl::FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { - - void **Bucket = GetBucketFor(ID, Buckets, NumBuckets); + unsigned IDHash = ID.ComputeHash(); + void **Bucket = GetBucketFor(IDHash, Buckets, NumBuckets); void *Probe = *Bucket; - InsertPos = 0; + InsertPos = nullptr; - FoldingSetNodeID OtherID; + FoldingSetNodeID TempID; while (Node *NodeInBucket = GetNextPtr(Probe)) { - GetNodeProfile(NodeInBucket, OtherID); - if (OtherID == ID) + if (NodeEquals(NodeInBucket, ID, IDHash, TempID)) return NodeInBucket; + TempID.clear(); Probe = NodeInBucket->getNextInBucket(); - OtherID.clear(); } // Didn't find the node, return null with the bucket as the InsertPos. InsertPos = Bucket; - return 0; + return nullptr; } /// InsertNode - Insert the specified node into the folding set, knowing that it /// is not already in the map. InsertPos must be obtained from /// FindNodeOrInsertPos. void FoldingSetImpl::InsertNode(Node *N, void *InsertPos) { - assert(N->getNextInBucket() == 0); + assert(!N->getNextInBucket()); // Do we need to grow the hashtable? if (NumNodes+1 > NumBuckets*2) { GrowHashTable(); - FoldingSetNodeID ID; - GetNodeProfile(N, ID); - InsertPos = GetBucketFor(ID, Buckets, NumBuckets); + FoldingSetNodeID TempID; + InsertPos = GetBucketFor(ComputeNodeHash(N, TempID), Buckets, NumBuckets); } ++NumNodes; @@ -288,7 +323,7 @@ void FoldingSetImpl::InsertNode(Node *N, void *InsertPos) { // If this is the first insertion into this bucket, its next pointer will be // 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) + if (!Next) Next = reinterpret_cast(reinterpret_cast(Bucket)|1); // Set the node's next pointer, and make the bucket point to the node. @@ -302,10 +337,10 @@ bool FoldingSetImpl::RemoveNode(Node *N) { // Because each bucket is a circular list, we don't need to compute N's hash // to remove it. void *Ptr = N->getNextInBucket(); - if (Ptr == 0) return false; // Not in folding set. + if (!Ptr) return false; // Not in folding set. --NumNodes; - N->SetNextInBucket(0); + N->SetNextInBucket(nullptr); // Remember what N originally pointed to, either a bucket or another node. void *NodeNextPtr = Ptr; @@ -355,7 +390,7 @@ FoldingSetImpl::Node *FoldingSetImpl::GetOrInsertNode(FoldingSetImpl::Node *N) { FoldingSetIteratorImpl::FoldingSetIteratorImpl(void **Bucket) { // Skip to the first non-null non-self-cycle bucket. while (*Bucket != reinterpret_cast(-1) && - (*Bucket == 0 || GetNextPtr(*Bucket) == 0)) + (!*Bucket || !GetNextPtr(*Bucket))) ++Bucket; NodePtr = static_cast(*Bucket); @@ -375,7 +410,7 @@ void FoldingSetIteratorImpl::advance() { do { ++Bucket; } while (*Bucket != reinterpret_cast(-1) && - (*Bucket == 0 || GetNextPtr(*Bucket) == 0)); + (!*Bucket || !GetNextPtr(*Bucket))); NodePtr = static_cast(*Bucket); } @@ -385,5 +420,5 @@ void FoldingSetIteratorImpl::advance() { // FoldingSetBucketIteratorImpl Implementation FoldingSetBucketIteratorImpl::FoldingSetBucketIteratorImpl(void **Bucket) { - Ptr = (*Bucket == 0 || GetNextPtr(*Bucket) == 0) ? (void*) Bucket : *Bucket; + Ptr = (!*Bucket || !GetNextPtr(*Bucket)) ? (void*) Bucket : *Bucket; }