X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FFoldingSet.cpp;h=6f7f5ea4cbf3cc09d910579ba03b1191f8d2e445;hb=ada530b4f552da1d122be0c6dbc936e689fc16fd;hp=7d0dca2cb13aa1dd2f3c024174808b9aeb557ef7;hpb=788a0c6a181ddb8f10b0f4b83af43b4469e9c73b;p=oota-llvm.git

diff --git a/lib/Support/FoldingSet.cpp b/lib/Support/FoldingSet.cpp
index 7d0dca2cb13..6f7f5ea4cbf 100644
--- a/lib/Support/FoldingSet.cpp
+++ b/lib/Support/FoldingSet.cpp
@@ -16,6 +16,7 @@
 
 #include "llvm/ADT/FoldingSet.h"
 #include "llvm/Support/MathExtras.h"
+#include <cassert>
 using namespace llvm;
 
 //===----------------------------------------------------------------------===//
@@ -41,7 +42,10 @@ void FoldingSetImpl::NodeID::AddInteger(unsigned I) {
 }
 void FoldingSetImpl::NodeID::AddInteger(uint64_t I) {
   Bits.push_back(unsigned(I));
-  Bits.push_back(unsigned(I >> 32));
+  
+  // If the integer is small, encode it just as 32-bits.
+  if ((uint64_t)(int)I != I)
+    Bits.push_back(unsigned(I >> 32));
 }
 void FoldingSetImpl::NodeID::AddFloat(float F) {
   Bits.push_back(FloatToBits(F));
@@ -51,21 +55,20 @@ void FoldingSetImpl::NodeID::AddDouble(double D) {
 }
 void FoldingSetImpl::NodeID::AddString(const std::string &String) {
   unsigned Size = String.size();
+  Bits.push_back(Size);
+  if (!Size) return;
+
   unsigned Units = Size / 4;
   unsigned Pos = 0;
   const unsigned *Base = (const unsigned *)String.data();
   
   // If the string is aligned do a bulk transfer.
-#if 0  // FIXME - Add insert to SmallVector (tested with vector)
   if (!((intptr_t)Base & 3)) {
-    Bits.insert(Bits.end(), Base, Base + Units);
-    Pos = Units * sizeof(unsigned);
+    Bits.append(Base, Base + Units);
+    Pos = (Units + 1) * 4;
   } else {
-#else
-  }
-#endif
     // Otherwise do it the hard way.
-    for ( Pos += 4; Pos < Size; Pos += 4) {
+    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) |
@@ -81,7 +84,7 @@ void FoldingSetImpl::NodeID::AddString(const std::string &String) {
   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;
-  case 0: return; // Nothing left.
+  default: return; // Nothing left.
   }
 
   Bits.push_back(V);
@@ -125,8 +128,8 @@ bool FoldingSetImpl::NodeID::operator==(const FoldingSetImpl::NodeID &RHS)const{
 /// 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.
+/// Nodes.  If NextInBucketPtr is a bucket pointer, this method returns null:
+/// use GetBucketPtr when this happens.
 static FoldingSetImpl::Node *GetNextPtr(void *NextInBucketPtr,
                                         void **Buckets, unsigned NumBuckets) {
   if (NextInBucketPtr >= Buckets && NextInBucketPtr < Buckets + NumBuckets)
@@ -152,8 +155,10 @@ static void **GetBucketFor(const FoldingSetImpl::NodeID &ID,
 //===----------------------------------------------------------------------===//
 // FoldingSetImpl Implementation
 
-FoldingSetImpl::FoldingSetImpl() : NumNodes(0) {
-  NumBuckets = 64;
+FoldingSetImpl::FoldingSetImpl(unsigned Log2InitSize) : NumNodes(0) {
+  assert(5 < Log2InitSize && Log2InitSize < 32 &&
+         "Initial hash table size out of range");
+  NumBuckets = 1 << Log2InitSize;
   Buckets = new void*[NumBuckets];
   memset(Buckets, 0, NumBuckets*sizeof(void*));
 }
@@ -179,7 +184,7 @@ void FoldingSetImpl::GrowHashTable() {
   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, OldBuckets, OldNumBuckets)) {
       // Figure out the next link, remove NodeInBucket from the old link.
       Probe = NodeInBucket->getNextInBucket();
       NodeInBucket->SetNextInBucket(0);
@@ -222,14 +227,16 @@ FoldingSetImpl::Node *FoldingSetImpl::FindNodeOrInsertPos(const NodeID &ID,
 /// 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;
     GetNodeProfile(ID, N);
     InsertPos = GetBucketFor(ID, Buckets, NumBuckets);
   }
+
+  ++NumNodes;
   
   /// The insert position is actually a bucket pointer.
   void **Bucket = static_cast<void**>(InsertPos);
@@ -241,7 +248,7 @@ void FoldingSetImpl::InsertNode(Node *N, void *InsertPos) {
   if (Next == 0)
     Next = Bucket;
 
-  // 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;
 }
@@ -250,15 +257,17 @@ void FoldingSetImpl::InsertNode(Node *N, void *InsertPos) {
 /// 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, Buckets, NumBuckets)) {
       // Advance pointer.