X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FSmallPtrSet.h;h=3bb883088c598d489f07534a446e096e6be93fb5;hb=b61054ff8f5568489109a0ccf2799307c3671309;hp=f1405fab9cb05d6e06028bb25d125c5e08663b9d;hpb=871dc240d06b40ea2194677d5a85957cbdbbbe60;p=oota-llvm.git

diff --git a/include/llvm/ADT/SmallPtrSet.h b/include/llvm/ADT/SmallPtrSet.h
index f1405fab9cb..3bb883088c5 100644
--- a/include/llvm/ADT/SmallPtrSet.h
+++ b/include/llvm/ADT/SmallPtrSet.h
@@ -15,11 +15,13 @@
 #ifndef LLVM_ADT_SMALLPTRSET_H
 #define LLVM_ADT_SMALLPTRSET_H
 
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 #include <cassert>
+#include <cstddef>
 #include <cstring>
 #include <iterator>
-#include "llvm/System/DataTypes.h"
-#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace llvm {
 
@@ -46,26 +48,26 @@ class SmallPtrSetIteratorImpl;
 class SmallPtrSetImpl {
   friend class SmallPtrSetIteratorImpl;
 protected:
-  /// CurArray - This is the current set of buckets.  If it points to
-  /// SmallArray, then the set is in 'small mode'.
+  /// SmallArray - Points to a fixed size set of buckets, used in 'small mode'.
+  const void **SmallArray;
+  /// CurArray - This is the current set of buckets.  If equal to SmallArray,
+  /// then the set is in 'small mode'.
   const void **CurArray;
   /// CurArraySize - The allocated size of CurArray, always a power of two.
   /// Note that CurArray points to an array that has CurArraySize+1 elements in
   /// it, so that the end iterator actually points to valid memory.
   unsigned CurArraySize;
 
-  // If small, this is # elts allocated consequtively
+  // If small, this is # elts allocated consecutively
   unsigned NumElements;
   unsigned NumTombstones;
-  const void *SmallArray[1];  // Must be last ivar.
 
   // Helper to copy construct a SmallPtrSet.
-  SmallPtrSetImpl(const SmallPtrSetImpl& that);
-  explicit SmallPtrSetImpl(unsigned SmallSize) {
+  SmallPtrSetImpl(const void **SmallStorage, const SmallPtrSetImpl& that);
+  explicit SmallPtrSetImpl(const void **SmallStorage, unsigned SmallSize) :
+    SmallArray(SmallStorage), CurArray(SmallStorage), CurArraySize(SmallSize) {
     assert(SmallSize && (SmallSize & (SmallSize-1)) == 0 &&
            "Initial size must be a power of two!");
-    CurArray = &SmallArray[0];
-    CurArraySize = SmallSize;
     // The end pointer, always valid, is set to a valid element to help the
     // iterator.
     CurArray[SmallSize] = 0;
@@ -123,19 +125,20 @@ protected:
   }
 
 private:
-  bool isSmall() const { return CurArray == &SmallArray[0]; }
+  bool isSmall() const { return CurArray == SmallArray; }
 
-  unsigned Hash(const void *Ptr) const {
-    return static_cast<unsigned>(((uintptr_t)Ptr >> 4) & (CurArraySize-1));
-  }
   const void * const *FindBucketFor(const void *Ptr) const;
   void shrink_and_clear();
 
   /// Grow - Allocate a larger backing store for the buckets and move it over.
-  void Grow();
+  void Grow(unsigned NewSize);
 
-  void operator=(const SmallPtrSetImpl &RHS);  // DO NOT IMPLEMENT.
+  void operator=(const SmallPtrSetImpl &RHS) LLVM_DELETED_FUNCTION;
 protected:
+  /// swap - Swaps the elements of two sets.
+  /// Note: This method assumes that both sets have the same small size.
+  void swap(SmallPtrSetImpl &RHS);
+
   void CopyFrom(const SmallPtrSetImpl &RHS);
 };
 
@@ -199,29 +202,29 @@ public:
   }
 };
 
-/// NextPowerOfTwo - This is a helper template that rounds N up to the next
-/// power of two.
+/// RoundUpToPowerOfTwo - This is a helper template that rounds N up to the next
+/// power of two (which means N itself if N is already a power of two).
 template<unsigned N>
-struct NextPowerOfTwo;
+struct RoundUpToPowerOfTwo;
 
-/// NextPowerOfTwoH - If N is not a power of two, increase it.  This is a helper
-/// template used to implement NextPowerOfTwo.
+/// RoundUpToPowerOfTwoH - If N is not a power of two, increase it.  This is a
+/// helper template used to implement RoundUpToPowerOfTwo.
 template<unsigned N, bool isPowerTwo>
-struct NextPowerOfTwoH {
+struct RoundUpToPowerOfTwoH {
   enum { Val = N };
 };
 template<unsigned N>
-struct NextPowerOfTwoH<N, false> {
+struct RoundUpToPowerOfTwoH<N, false> {
   enum {
     // We could just use NextVal = N+1, but this converges faster.  N|(N-1) sets
     // the right-most zero bits to one all at once, e.g. 0b0011000 -> 0b0011111.
-    Val = NextPowerOfTwo<(N|(N-1)) + 1>::Val
+    Val = RoundUpToPowerOfTwo<(N|(N-1)) + 1>::Val
   };
 };
 
 template<unsigned N>
-struct NextPowerOfTwo {
-  enum { Val = NextPowerOfTwoH<N, (N&(N-1)) == 0>::Val };
+struct RoundUpToPowerOfTwo {
+  enum { Val = RoundUpToPowerOfTwoH<N, (N&(N-1)) == 0>::Val };
 };
   
 
@@ -232,15 +235,17 @@ struct NextPowerOfTwo {
 template<class PtrType, unsigned SmallSize>
 class SmallPtrSet : public SmallPtrSetImpl {
   // Make sure that SmallSize is a power of two, round up if not.
-  enum { SmallSizePowTwo = NextPowerOfTwo<SmallSize>::Val };
-  void *SmallArray[SmallSizePowTwo+1];
+  enum { SmallSizePowTwo = RoundUpToPowerOfTwo<SmallSize>::Val };
+  /// SmallStorage - Fixed size storage used in 'small mode'.  The extra element
+  /// ensures that the end iterator actually points to valid memory.
+  const void *SmallStorage[SmallSizePowTwo+1];
   typedef PointerLikeTypeTraits<PtrType> PtrTraits;
 public:
-  SmallPtrSet() : SmallPtrSetImpl(SmallSizePowTwo) {}
-  SmallPtrSet(const SmallPtrSet &that) : SmallPtrSetImpl(that) {}
+  SmallPtrSet() : SmallPtrSetImpl(SmallStorage, SmallSizePowTwo) {}
+  SmallPtrSet(const SmallPtrSet &that) : SmallPtrSetImpl(SmallStorage, that) {}
 
   template<typename It>
-  SmallPtrSet(It I, It E) : SmallPtrSetImpl(SmallSizePowTwo) {
+  SmallPtrSet(It I, It E) : SmallPtrSetImpl(SmallStorage, SmallSizePowTwo) {
     insert(I, E);
   }
 
@@ -284,8 +289,20 @@ public:
     return *this;
   }
 
+  /// swap - Swaps the elements of two sets.
+  void swap(SmallPtrSet<PtrType, SmallSize> &RHS) {
+    SmallPtrSetImpl::swap(RHS);
+  }
 };
 
 }
 
+namespace std {
+  /// Implement std::swap in terms of SmallPtrSet swap.
+  template<class T, unsigned N>
+  inline void swap(llvm::SmallPtrSet<T, N> &LHS, llvm::SmallPtrSet<T, N> &RHS) {
+    LHS.swap(RHS);
+  }
+}
+
 #endif