X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FSmallVector.h;h=e93177cdcb748338c28a46fca0ba44c24e2a9a60;hb=a727d5502c8e23c090da658bf14c5ebc1169a070;hp=3e952ac4475946245c09eca3c2bd903812d91928;hpb=8e10f5b8113a5080fc916d1123377292ef2f6012;p=oota-llvm.git

diff --git a/include/llvm/ADT/SmallVector.h b/include/llvm/ADT/SmallVector.h
index 3e952ac4475..e93177cdcb7 100644
--- a/include/llvm/ADT/SmallVector.h
+++ b/include/llvm/ADT/SmallVector.h
@@ -18,65 +18,70 @@
 #include <iterator>
 #include <memory>
 
+#ifdef _MSC_VER
+namespace std {
+#if _MSC_VER <= 1310
+  // Work around flawed VC++ implementation of std::uninitialized_copy.  Define
+  // additional overloads so that elements with pointer types are recognized as
+  // scalars and not objects, causing bizarre type conversion errors.
+  template<class T1, class T2>
+  inline _Scalar_ptr_iterator_tag _Ptr_cat(T1 **, T2 **) {
+    _Scalar_ptr_iterator_tag _Cat;
+    return _Cat;
+  }
+
+  template<class T1, class T2>
+  inline _Scalar_ptr_iterator_tag _Ptr_cat(T1* const *, T2 **) {
+    _Scalar_ptr_iterator_tag _Cat;
+    return _Cat;
+  }
+#else
+// FIXME: It is not clear if the problem is fixed in VS 2005.  What is clear
+// is that the above hack won't work if it wasn't fixed.
+#endif
+}
+#endif
+
 namespace llvm {
 
-/// SmallVector - This is a 'vector' (really, a variable-sized array), optimized
-/// for the case when the array is small.  It contains some number of elements
-/// in-place, which allows it to avoid heap allocation when the actual number of
-/// elements is below that threshold.  This allows normal "small" cases to be
-/// fast without losing generality for large inputs.
-///
-/// Note that this does not attempt to be exception safe.
-///
-template <typename T, unsigned N>
-class SmallVector {
+/// SmallVectorImpl - This class consists of common code factored out of the
+/// SmallVector class to reduce code duplication based on the SmallVector 'N'
+/// template parameter.
+template <typename T>
+class SmallVectorImpl {
+protected:
+  T *Begin, *End, *Capacity;
+  
   // Allocate raw space for N elements of type T.  If T has a ctor or dtor, we
   // don't want it to be automatically run, so we need to represent the space as
   // something else.  An array of char would work great, but might not be
   // aligned sufficiently.  Instead, we either use GCC extensions, or some
   // number of union instances for the space, which guarantee maximal alignment.
+protected:
+#ifdef __GNUC__
+  typedef char U;
+  U FirstEl __attribute__((aligned));
+#else
   union U {
     double D;
     long double LD;
     long long L;
     void *P;
-  };
-  
-  /// InlineElts - These are the 'N' elements that are stored inline in the body
-  /// of the vector
-  U InlineElts[(sizeof(T)*N+sizeof(U)-1)/sizeof(U)];
-  T *Begin, *End, *Capacity;
+  } FirstEl;
+#endif
+  // Space after 'FirstEl' is clobbered, do not add any instance vars after it.
 public:
   // Default ctor - Initialize to empty.
-  SmallVector() : Begin((T*)InlineElts), End(Begin), Capacity(Begin+N) {
+  SmallVectorImpl(unsigned N)
+    : Begin((T*)&FirstEl), End((T*)&FirstEl), Capacity((T*)&FirstEl+N) {
   }
   
-  template<typename ItTy>
-  SmallVector(ItTy S, ItTy E)
-    : Begin((T*)InlineElts), End(Begin), Capacity(Begin+N) {
-    append(S, E);
-  }
-  
-  SmallVector(const SmallVector &RHS) {
-    unsigned RHSSize = RHS.size();
-    Begin = (T*)InlineElts;
-
-    // Doesn't fit in the small case?  Allocate space.
-    if (RHSSize > N) {
-      End = Capacity = Begin;
-      grow(RHSSize);
-    }
-    End = Begin+RHSSize;
-    Capacity = Begin+N;
-    std::uninitialized_copy(RHS.begin(), RHS.end(), Begin);
-  }
-  ~SmallVector() {
+  ~SmallVectorImpl() {
     // Destroy the constructed elements in the vector.
-    for (iterator I = Begin, E = End; I != E; ++I)
-      I->~T();
+    destroy_range(Begin, End);
 
     // If this wasn't grown from the inline copy, deallocate the old space.
-    if ((void*)Begin != (void*)InlineElts)
+    if (!isSmall())
       delete[] (char*)Begin;
   }
   
@@ -102,6 +107,13 @@ public:
     return Begin[idx];
   }
   
+  reference front() {
+    return begin()[0];
+  }
+  const_reference front() const {
+    return begin()[0];
+  }
+  
   reference back() {
     return end()[-1];
   }
@@ -126,12 +138,41 @@ public:
   }
   
   void clear() {
-    while (End != Begin) {
-      End->~T();
-      --End;
+    destroy_range(Begin, End);
+    End = Begin;
+  }
+  
+  void resize(unsigned N) {
+    if (N < size()) {
+      destroy_range(Begin+N, End);
+      End = Begin+N;
+    } else if (N > size()) {
+      if (Begin+N > Capacity)
+        grow(N);
+      construct_range(End, Begin+N, T());
+      End = Begin+N;
     }
   }
   
+  void resize(unsigned N, const T &NV) {
+    if (N < size()) {
+      destroy_range(Begin+N, End);
+      End = Begin+N;
+    } else if (N > size()) {
+      if (Begin+N > Capacity)
+        grow(N);
+      construct_range(End, Begin+N, NV);
+      End = Begin+N;
+    }
+  }
+  
+  void reserve(unsigned N) {
+    if (unsigned(Capacity-Begin) < N)
+      grow(N);
+  }
+  
+  void swap(SmallVectorImpl &RHS);
+  
   /// append - Add the specified range to the end of the SmallVector.
   ///
   template<typename in_iter>
@@ -151,86 +192,294 @@ public:
     if (Begin+NumElts > Capacity)
       grow(NumElts);
     End = Begin+NumElts;
-    for (; NumElts; --NumElts)
-      new (Begin+NumElts-1) T(Elt);
+    construct_range(Begin, End, Elt);
   }
   
-  const SmallVector &operator=(const SmallVector &RHS) {
-    // Avoid self-assignment.
-    if (this == &RHS) return *this;
+  void erase(iterator I) {
+    // Shift all elts down one.
+    std::copy(I+1, End, I);
+    // Drop the last elt.
+    pop_back();
+  }
+  
+  void erase(iterator S, iterator E) {
+    // Shift all elts down.
+    iterator I = std::copy(E, End, S);
+    // Drop the last elts.
+    destroy_range(I, End);
+    End = I;
+  }
+  
+  iterator insert(iterator I, const T &Elt) {
+    if (I == End) {  // Important special case for empty vector.
+      push_back(Elt);
+      return end()-1;
+    }
+    
+    if (End < Capacity) {
+  Retry:
+      new (End) T(back());
+      ++End;
+      // Push everything else over.
+      std::copy_backward(I, End-1, End);
+      *I = Elt;
+      return I;
+    }
+    unsigned EltNo = I-Begin;
+    grow();
+    I = Begin+EltNo;
+    goto Retry;
+  }
+  
+  template<typename ItTy>
+  iterator insert(iterator I, ItTy From, ItTy To) {
+    if (I == End) {  // Important special case for empty vector.
+      append(From, To);
+      return end()-1;
+    }
+    
+    unsigned NumToInsert = std::distance(From, To);
+    // Convert iterator to elt# to avoid invalidating iterator when we reserve()
+    unsigned InsertElt = I-begin();
+    
+    // Ensure there is enough space.
+    reserve(size() + NumToInsert);
     
-    // If we already have sufficient space, assign the common elements, then
-    // destroy any excess.
-    unsigned RHSSize = RHS.size();
-    unsigned CurSize = size();
-    if (CurSize >= RHSSize) {
-      // Assign common elements.
-      std::copy(RHS.Begin, RHS.Begin+RHSSize, Begin);
+    // Uninvalidate the iterator.
+    I = begin()+InsertElt;
+    
+    // If we already have this many elements in the collection, append the
+    // dest elements at the end, then copy over the appropriate elements.  Since
+    // we already reserved space, we know that this won't reallocate the vector.
+    if (size() >= NumToInsert) {
+      T *OldEnd = End;
+      append(End-NumToInsert, End);
       
-      // Destroy excess elements.
-      for (unsigned i = RHSSize; i != CurSize; ++i)
-        Begin[i].~T();
+      // Copy the existing elements that get replaced.
+      std::copy(I, OldEnd-NumToInsert, I+NumToInsert);
       
-      // Trim.
-      End = Begin + RHSSize;
-      return *this;
+      std::copy(From, To, I);
+      return I;
     }
+
+    // Otherwise, we're inserting more elements than exist already, and we're
+    // not inserting at the end.
     
-    // If we have to grow to have enough elements, destroy the current elements.
-    // This allows us to avoid copying them during the grow.
-    if (Capacity-Begin < RHSSize) {
-      // Destroy current elements.
-      for (iterator I = Begin, E = End; I != E; ++I)
-        I->~T();
-      End = Begin;
-      CurSize = 0;
-      grow(RHSSize);
-    } else if (CurSize) {
-      // Otherwise, use assignment for the already-constructed elements.
-      std::copy(RHS.Begin, RHS.Begin+CurSize, Begin);
-    }
+    // Copy over the elements that we're about to overwrite.
+    T *OldEnd = End;
+    End += NumToInsert;
+    unsigned NumOverwritten = OldEnd-I;
+    std::uninitialized_copy(I, OldEnd, End-NumOverwritten);
     
-    // Copy construct the new elements in place.
-    std::uninitialized_copy(RHS.Begin+CurSize, RHS.End, Begin+CurSize);
+    // Replace the overwritten part.
+    std::copy(From, From+NumOverwritten, I);
     
-    // Set end.
-    End = Begin+RHSSize;
+    // Insert the non-overwritten middle part.
+    std::uninitialized_copy(From+NumOverwritten, To, OldEnd);
+    return I;
   }
   
+  const SmallVectorImpl &operator=(const SmallVectorImpl &RHS);
+  
 private:
   /// isSmall - Return true if this is a smallvector which has not had dynamic
   /// memory allocated for it.
   bool isSmall() const {
-    return (void*)Begin == (void*)InlineElts;
+    return (void*)Begin == (void*)&FirstEl;
   }
 
   /// grow - double the size of the allocated memory, guaranteeing space for at
   /// least one more element or MinSize if specified.
-  void grow(unsigned MinSize = 0) {
-    unsigned CurCapacity = Capacity-Begin;
-    unsigned CurSize = size();
-    unsigned NewCapacity = 2*CurCapacity;
-    if (NewCapacity < MinSize)
-      NewCapacity = MinSize;
-    T *NewElts = reinterpret_cast<T*>(new char[NewCapacity*sizeof(T)]);
-
-    // Copy the elements over.
-    std::uninitialized_copy(Begin, End, NewElts);
+  void grow(unsigned MinSize = 0);
+
+  void construct_range(T *S, T *E, const T &Elt) {
+    for (; S != E; ++S)
+      new (S) T(Elt);
+  }
+  
+  void destroy_range(T *S, T *E) {
+    while (S != E) {
+      --E;
+      E->~T();
+    }
+  }
+};
+
+// Define this out-of-line to dissuade the C++ compiler from inlining it.
+template <typename T>
+void SmallVectorImpl<T>::grow(unsigned MinSize) {
+  unsigned CurCapacity = unsigned(Capacity-Begin);
+  unsigned CurSize = unsigned(size());
+  unsigned NewCapacity = 2*CurCapacity;
+  if (NewCapacity < MinSize)
+    NewCapacity = MinSize;
+  T *NewElts = reinterpret_cast<T*>(new char[NewCapacity*sizeof(T)]);
+  
+  // Copy the elements over.
+  std::uninitialized_copy(Begin, End, NewElts);
+  
+  // Destroy the original elements.
+  destroy_range(Begin, End);
+  
+  // If this wasn't grown from the inline copy, deallocate the old space.
+  if (!isSmall())
+    delete[] (char*)Begin;
+  
+  Begin = NewElts;
+  End = NewElts+CurSize;
+  Capacity = Begin+NewCapacity;
+}
+
+template <typename T>
+void SmallVectorImpl<T>::swap(SmallVectorImpl<T> &RHS) {
+  if (this == &RHS) return;
+  
+  // We can only avoid copying elements if neither vector is small.
+  if (!isSmall() && !RHS.isSmall()) {
+    std::swap(Begin, RHS.Begin);
+    std::swap(End, RHS.End);
+    std::swap(Capacity, RHS.Capacity);
+    return;
+  }
+  if (Begin+RHS.size() > Capacity)
+    grow(RHS.size());
+  if (RHS.begin()+size() > RHS.Capacity)
+    RHS.grow(size());
+  
+  // Swap the shared elements.
+  unsigned NumShared = size();
+  if (NumShared > RHS.size()) NumShared = RHS.size();
+  for (unsigned i = 0; i != NumShared; ++i)
+    std::swap(Begin[i], RHS[i]);
+  
+  // Copy over the extra elts.
+  if (size() > RHS.size()) {
+    unsigned EltDiff = size() - RHS.size();
+    std::uninitialized_copy(Begin+NumShared, End, RHS.End);
+    RHS.End += EltDiff;
+    destroy_range(Begin+NumShared, End);
+    End = Begin+NumShared;
+  } else if (RHS.size() > size()) {
+    unsigned EltDiff = RHS.size() - size();
+    std::uninitialized_copy(RHS.Begin+NumShared, RHS.End, End);
+    End += EltDiff;
+    destroy_range(RHS.Begin+NumShared, RHS.End);
+    RHS.End = RHS.Begin+NumShared;
+  }
+}
+  
+template <typename T>
+const SmallVectorImpl<T> &
+SmallVectorImpl<T>::operator=(const SmallVectorImpl<T> &RHS) {
+  // Avoid self-assignment.
+  if (this == &RHS) return *this;
+  
+  // If we already have sufficient space, assign the common elements, then
+  // destroy any excess.
+  unsigned RHSSize = unsigned(RHS.size());
+  unsigned CurSize = unsigned(size());
+  if (CurSize >= RHSSize) {
+    // Assign common elements.
+    iterator NewEnd = std::copy(RHS.Begin, RHS.Begin+RHSSize, Begin);
     
-    // Destroy the original elements.
-    for (iterator I = Begin, E = End; I != E; ++I)
-      I->~T();
+    // Destroy excess elements.
+    destroy_range(NewEnd, End);
     
-    // If this wasn't grown from the inline copy, deallocate the old space.
-    if (!isSmall())
-      delete[] (char*)Begin;
+    // Trim.
+    End = NewEnd;
+    return *this;
+  }
+  
+  // If we have to grow to have enough elements, destroy the current elements.
+  // This allows us to avoid copying them during the grow.
+  if (unsigned(Capacity-Begin) < RHSSize) {
+    // Destroy current elements.
+    destroy_range(Begin, End);
+    End = Begin;
+    CurSize = 0;
+    grow(RHSSize);
+  } else if (CurSize) {
+    // Otherwise, use assignment for the already-constructed elements.
+    std::copy(RHS.Begin, RHS.Begin+CurSize, Begin);
+  }
+  
+  // Copy construct the new elements in place.
+  std::uninitialized_copy(RHS.Begin+CurSize, RHS.End, Begin+CurSize);
+  
+  // Set end.
+  End = Begin+RHSSize;
+  return *this;
+}
+  
+/// SmallVector - This is a 'vector' (really, a variable-sized array), optimized
+/// for the case when the array is small.  It contains some number of elements
+/// in-place, which allows it to avoid heap allocation when the actual number of
+/// elements is below that threshold.  This allows normal "small" cases to be
+/// fast without losing generality for large inputs.
+///
+/// Note that this does not attempt to be exception safe.
+///
+template <typename T, unsigned N>
+class SmallVector : public SmallVectorImpl<T> {
+  /// InlineElts - These are 'N-1' elements that are stored inline in the body
+  /// of the vector.  The extra '1' element is stored in SmallVectorImpl.
+  typedef typename SmallVectorImpl<T>::U U;
+  enum {
+    // MinUs - The number of U's require to cover N T's.
+    MinUs = (sizeof(T)*N+sizeof(U)-1)/sizeof(U),
     
-    Begin = NewElts;
-    End = NewElts+CurSize;
-    Capacity = Begin+NewCapacity;
+    // NumInlineEltsElts - The number of elements actually in this array.  There
+    // is already one in the parent class, and we have to round up to avoid
+    // having a zero-element array.
+    NumInlineEltsElts = (MinUs - 1) > 0 ? (MinUs - 1) : 1,
+    
+    // NumTsAvailable - The number of T's we actually have space for, which may
+    // be more than N due to rounding.
+    NumTsAvailable = (NumInlineEltsElts+1)*sizeof(U) / sizeof(T)
+  };
+  U InlineElts[NumInlineEltsElts];
+public:  
+  SmallVector() : SmallVectorImpl<T>(NumTsAvailable) {
+  }
+  
+  SmallVector(unsigned Size, const T &Value)
+    : SmallVectorImpl<T>(NumTsAvailable) {
+    this->reserve(Size);
+    while (Size--)
+      push_back(Value);
+  }
+  
+  template<typename ItTy>
+  SmallVector(ItTy S, ItTy E) : SmallVectorImpl<T>(NumTsAvailable) {
+    append(S, E);
+  }
+  
+  SmallVector(const SmallVector &RHS) : SmallVectorImpl<T>(NumTsAvailable) {
+    operator=(RHS);
+  }
+  
+  const SmallVector &operator=(const SmallVector &RHS) {
+    SmallVectorImpl<T>::operator=(RHS);
+    return *this;
   }
 };
 
 } // End llvm namespace
 
+namespace std {
+  /// Implement std::swap in terms of SmallVector swap.
+  template<typename T>
+  inline void
+  swap(llvm::SmallVectorImpl<T> &LHS, llvm::SmallVectorImpl<T> &RHS) {
+    LHS.swap(RHS);
+  }
+  
+  /// Implement std::swap in terms of SmallVector swap.
+  template<typename T, unsigned N>
+  inline void
+  swap(llvm::SmallVector<T, N> &LHS, llvm::SmallVector<T, N> &RHS) {
+    LHS.swap(RHS);
+  }
+}
+
 #endif