X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FStringMap.h;h=b4497a276d0e58331f54b528dd9b0e6353f87336;hb=5c5b3cf5b8af06b8e9347f3f45e8c67438ffd446;hp=1b20f4fdd9c33b97829b4a5359e0ad12ee50d9ff;hpb=061d21eaf8fcdb19b85db0755c208acbba7c8ef4;p=oota-llvm.git

diff --git a/include/llvm/ADT/StringMap.h b/include/llvm/ADT/StringMap.h
index 1b20f4fdd9c..b4497a276d0 100644
--- a/include/llvm/ADT/StringMap.h
+++ b/include/llvm/ADT/StringMap.h
@@ -17,7 +17,6 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Allocator.h"
 #include <cstring>
-#include <string>
 
 namespace llvm {
   template<typename ValueT>
@@ -52,20 +51,11 @@ public:
 /// StringMapImpl - This is the base class of StringMap that is shared among
 /// all of its instantiations.
 class StringMapImpl {
-public:
-  /// ItemBucket - The hash table consists of an array of these.  If Item is
-  /// non-null, this is an extant entry, otherwise, it is a hole.
-  struct ItemBucket {
-    /// FullHashValue - This remembers the full hash value of the key for
-    /// easy scanning.
-    unsigned FullHashValue;
-
-    /// Item - This is a pointer to the actual item object.
-    StringMapEntryBase *Item;
-  };
-
 protected:
-  ItemBucket *TheTable;
+  // Array of NumBuckets pointers to entries, null pointers are holes.
+  // TheTable[NumBuckets] contains a sentinel value for easy iteration. Follwed
+  // by an array of the actual hash values as unsigned integers.
+  StringMapEntryBase **TheTable;
   unsigned NumBuckets;
   unsigned NumItems;
   unsigned NumTombstones;
@@ -81,16 +71,6 @@ protected:
   StringMapImpl(unsigned InitSize, unsigned ItemSize);
   void RehashTable();
 
-  /// ShouldRehash - Return true if the table should be rehashed after a new
-  /// element was recently inserted.
-  bool ShouldRehash() const {
-    // If the hash table is now more than 3/4 full, or if fewer than 1/8 of
-    // the buckets are empty (meaning that many are filled with tombstones),
-    // grow the table.
-    return NumItems*4 > NumBuckets*3 ||
-           NumBuckets-(NumItems+NumTombstones) < NumBuckets/8;
-  }
-
   /// LookupBucketFor - Look up the bucket that the specified string should end
   /// up in.  If it already exists as a key in the map, the Item pointer for the
   /// specified bucket will be non-null.  Otherwise, it will be null.  In either
@@ -137,8 +117,8 @@ public:
   StringMapEntry(unsigned strLen, const ValueTy &V)
     : StringMapEntryBase(strLen), second(V) {}
 
-  StringRef getKey() const { 
-    return StringRef(getKeyData(), getKeyLength()); 
+  StringRef getKey() const {
+    return StringRef(getKeyData(), getKeyLength());
   }
 
   const ValueTy &getValue() const { return second; }
@@ -151,7 +131,7 @@ public:
   /// StringMapEntry object.
   const char *getKeyData() const {return reinterpret_cast<const char*>(this+1);}
 
-  const char *first() const { return getKeyData(); }
+  StringRef first() const { return StringRef(getKeyData(), getKeyLength()); }
 
   /// Create - Create a StringMapEntry for the specified key and default
   /// construct the value.
@@ -167,7 +147,7 @@ public:
 
     unsigned AllocSize = static_cast<unsigned>(sizeof(StringMapEntry))+
       KeyLength+1;
-    unsigned Alignment = alignof<StringMapEntry>();
+    unsigned Alignment = alignOf<StringMapEntry>();
 
     StringMapEntry *NewItem =
       static_cast<StringMapEntry*>(Allocator.Allocate(AllocSize,Alignment));
@@ -216,14 +196,14 @@ public:
   static const StringMapEntry &GetStringMapEntryFromValue(const ValueTy &V) {
     return GetStringMapEntryFromValue(const_cast<ValueTy&>(V));
   }
-  
+
   /// GetStringMapEntryFromKeyData - Given key data that is known to be embedded
   /// into a StringMapEntry, return the StringMapEntry itself.
   static StringMapEntry &GetStringMapEntryFromKeyData(const char *KeyData) {
     char *Ptr = const_cast<char*>(KeyData) - sizeof(StringMapEntry<ValueTy>);
     return *reinterpret_cast<StringMapEntry*>(Ptr);
   }
-  
+
 
   /// Destroy - Destroy this StringMapEntry, releasing memory back to the
   /// specified allocator.
@@ -242,9 +222,6 @@ public:
 };
 
 
-template <typename T> struct ReferenceAdder { typedef T& result; };
-template <typename T> struct ReferenceAdder<T&> { typedef T result; };
-  
 /// StringMap - This is an unconventional map that is specialized for handling
 /// keys that are "strings", which are basically ranges of bytes. This does some
 /// funky memory allocation and hashing things to make it extremely efficient,
@@ -252,23 +229,26 @@ template <typename T> struct ReferenceAdder<T&> { typedef T result; };
 template<typename ValueTy, typename AllocatorTy = MallocAllocator>
 class StringMap : public StringMapImpl {
   AllocatorTy Allocator;
-  typedef StringMapEntry<ValueTy> MapEntryTy;
 public:
+  typedef StringMapEntry<ValueTy> MapEntryTy;
+  
   StringMap() : StringMapImpl(static_cast<unsigned>(sizeof(MapEntryTy))) {}
   explicit StringMap(unsigned InitialSize)
     : StringMapImpl(InitialSize, static_cast<unsigned>(sizeof(MapEntryTy))) {}
-  
+
   explicit StringMap(AllocatorTy A)
     : StringMapImpl(static_cast<unsigned>(sizeof(MapEntryTy))), Allocator(A) {}
 
-  explicit StringMap(const StringMap &RHS)
+  StringMap(const StringMap &RHS)
     : StringMapImpl(static_cast<unsigned>(sizeof(MapEntryTy))) {
     assert(RHS.empty() &&
            "Copy ctor from non-empty stringmap not implemented yet!");
+    (void)RHS;
   }
   void operator=(const StringMap &RHS) {
     assert(RHS.empty() &&
            "assignment from non-empty stringmap not implemented yet!");
+    (void)RHS;
     clear();
   }
 
@@ -301,13 +281,13 @@ public:
   iterator find(StringRef Key) {
     int Bucket = FindKey(Key);
     if (Bucket == -1) return end();
-    return iterator(TheTable+Bucket);
+    return iterator(TheTable+Bucket, true);
   }
 
   const_iterator find(StringRef Key) const {
     int Bucket = FindKey(Key);
     if (Bucket == -1) return end();
-    return const_iterator(TheTable+Bucket);
+    return const_iterator(TheTable+Bucket, true);
   }
 
    /// lookup - Return the entry for the specified key, or a default
@@ -319,7 +299,7 @@ public:
     return ValueTy();
   }
 
-  ValueTy& operator[](StringRef Key) {
+  ValueTy &operator[](StringRef Key) {
     return GetOrCreateValue(Key).getValue();
   }
 
@@ -332,17 +312,17 @@ public:
   /// insert it and return true.
   bool insert(MapEntryTy *KeyValue) {
     unsigned BucketNo = LookupBucketFor(KeyValue->getKey());
-    ItemBucket &Bucket = TheTable[BucketNo];
-    if (Bucket.Item && Bucket.Item != getTombstoneVal())
+    StringMapEntryBase *&Bucket = TheTable[BucketNo];
+    if (Bucket && Bucket != getTombstoneVal())
       return false;  // Already exists in map.
 
-    if (Bucket.Item == getTombstoneVal())
+    if (Bucket == getTombstoneVal())
       --NumTombstones;
-    Bucket.Item = KeyValue;
+    Bucket = KeyValue;
     ++NumItems;
+    assert(NumItems + NumTombstones <= NumBuckets);
 
-    if (ShouldRehash())
-      RehashTable();
+    RehashTable();
     return true;
   }
 
@@ -352,59 +332,48 @@ public:
 
     // Zap all values, resetting the keys back to non-present (not tombstone),
     // which is safe because we're removing all elements.
-    for (ItemBucket *I = TheTable, *E = TheTable+NumBuckets; I != E; ++I) {
-      if (I->Item && I->Item != getTombstoneVal()) {
-        static_cast<MapEntryTy*>(I->Item)->Destroy(Allocator);
-        I->Item = 0;
+    for (unsigned I = 0, E = NumBuckets; I != E; ++I) {
+      StringMapEntryBase *&Bucket = TheTable[I];
+      if (Bucket && Bucket != getTombstoneVal()) {
+        static_cast<MapEntryTy*>(Bucket)->Destroy(Allocator);
+        Bucket = 0;
       }
     }
 
     NumItems = 0;
+    NumTombstones = 0;
   }
 
   /// GetOrCreateValue - Look up the specified key in the table.  If a value
   /// exists, return it.  Otherwise, default construct a value, insert it, and
   /// return.
   template <typename InitTy>
-  StringMapEntry<ValueTy> &GetOrCreateValue(StringRef Key,
-                                            InitTy Val) {
+  MapEntryTy &GetOrCreateValue(StringRef Key, InitTy Val) {
     unsigned BucketNo = LookupBucketFor(Key);
-    ItemBucket &Bucket = TheTable[BucketNo];
-    if (Bucket.Item && Bucket.Item != getTombstoneVal())
-      return *static_cast<MapEntryTy*>(Bucket.Item);
+    StringMapEntryBase *&Bucket = TheTable[BucketNo];
+    if (Bucket && Bucket != getTombstoneVal())
+      return *static_cast<MapEntryTy*>(Bucket);
 
     MapEntryTy *NewItem =
       MapEntryTy::Create(Key.begin(), Key.end(), Allocator, Val);
 
-    if (Bucket.Item == getTombstoneVal())
+    if (Bucket == getTombstoneVal())
       --NumTombstones;
     ++NumItems;
+    assert(NumItems + NumTombstones <= NumBuckets);
 
     // Fill in the bucket for the hash table.  The FullHashValue was already
     // filled in by LookupBucketFor.
-    Bucket.Item = NewItem;
+    Bucket = NewItem;
 
-    if (ShouldRehash())
-      RehashTable();
+    RehashTable();
     return *NewItem;
   }
 
-  StringMapEntry<ValueTy> &GetOrCreateValue(StringRef Key) {
+  MapEntryTy &GetOrCreateValue(StringRef Key) {
     return GetOrCreateValue(Key, ValueTy());
   }
 
-  template <typename InitTy>
-  StringMapEntry<ValueTy> &GetOrCreateValue(const char *KeyStart,
-                                            const char *KeyEnd,
-                                            InitTy Val) {
-    return GetOrCreateValue(StringRef(KeyStart, KeyEnd - KeyStart), Val);
-  }
-
-  StringMapEntry<ValueTy> &GetOrCreateValue(const char *KeyStart,
-                                            const char *KeyEnd) {
-    return GetOrCreateValue(StringRef(KeyStart, KeyEnd - KeyStart));
-  }
-
   /// remove - Remove the specified key/value pair from the map, but do not
   /// erase it.  This aborts if the key is not in the map.
   void remove(MapEntryTy *KeyValue) {
@@ -434,21 +403,21 @@ public:
 template<typename ValueTy>
 class StringMapConstIterator {
 protected:
-  StringMapImpl::ItemBucket *Ptr;
+  StringMapEntryBase **Ptr;
 public:
   typedef StringMapEntry<ValueTy> value_type;
 
-  explicit StringMapConstIterator(StringMapImpl::ItemBucket *Bucket,
+  explicit StringMapConstIterator(StringMapEntryBase **Bucket,
                                   bool NoAdvance = false)
   : Ptr(Bucket) {
     if (!NoAdvance) AdvancePastEmptyBuckets();
   }
 
   const value_type &operator*() const {
-    return *static_cast<StringMapEntry<ValueTy>*>(Ptr->Item);
+    return *static_cast<StringMapEntry<ValueTy>*>(*Ptr);
   }
   const value_type *operator->() const {
-    return static_cast<StringMapEntry<ValueTy>*>(Ptr->Item);
+    return static_cast<StringMapEntry<ValueTy>*>(*Ptr);
   }
 
   bool operator==(const StringMapConstIterator &RHS) const {
@@ -469,7 +438,7 @@ public:
 
 private:
   void AdvancePastEmptyBuckets() {
-    while (Ptr->Item == 0 || Ptr->Item == StringMapImpl::getTombstoneVal())
+    while (*Ptr == 0 || *Ptr == StringMapImpl::getTombstoneVal())
       ++Ptr;
   }
 };
@@ -477,15 +446,15 @@ private:
 template<typename ValueTy>
 class StringMapIterator : public StringMapConstIterator<ValueTy> {
 public:
-  explicit StringMapIterator(StringMapImpl::ItemBucket *Bucket,
+  explicit StringMapIterator(StringMapEntryBase **Bucket,
                              bool NoAdvance = false)
     : StringMapConstIterator<ValueTy>(Bucket, NoAdvance) {
   }
   StringMapEntry<ValueTy> &operator*() const {
-    return *static_cast<StringMapEntry<ValueTy>*>(this->Ptr->Item);
+    return *static_cast<StringMapEntry<ValueTy>*>(*this->Ptr);
   }
   StringMapEntry<ValueTy> *operator->() const {
-    return static_cast<StringMapEntry<ValueTy>*>(this->Ptr->Item);
+    return static_cast<StringMapEntry<ValueTy>*>(*this->Ptr);
   }
 };