libcxx initial import

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@103490 91177308-0d34-0410-b5e6-96231b3b80d8

test/containers/stack_allocator.h

@@ -0,0 +1,52 @@
+#ifndef STACK_ALLOCATOR_H
+#define STACK_ALLOCATOR_H
+
+#include <cstddef>
+#include <new>
+
+template <class T, std::size_t N>
+class stack_allocator
+{
+    char buf_[sizeof(T)*N];
+    char* ptr_;
+public:
+    typedef T                 value_type;
+    typedef value_type*       pointer;
+    typedef const value_type* const_pointer;
+    typedef value_type&       reference;
+    typedef const value_type& const_reference;
+    typedef std::size_t       size_type;
+    typedef std::ptrdiff_t    difference_type;
+
+    template <class U> struct rebind {typedef stack_allocator<U, N> other;};
+
+    stack_allocator() : ptr_(buf_) {}
+
+private:
+    stack_allocator(const stack_allocator&);// = delete;
+    stack_allocator& operator=(const stack_allocator&);// = delete;
+
+public:
+    pointer allocate(size_type n, const void* = 0)
+    {
+        if (n > N - (ptr_ - buf_) / sizeof(value_type))
+            throw std::bad_alloc();
+        pointer r = (T*)ptr_;
+        ptr_ += n * sizeof(T);
+        return r;
+    }
+    void deallocate(pointer p, size_type n)
+    {
+        if ((char*)(p + n) == ptr_)
+            ptr_ = (char*)p;
+    }
+
+    size_type max_size() const {return N;}
+};
+
+template <class T, std::size_t N>
+inline
+void
+swap(stack_allocator<T, N>& x, stack_allocator<T, N>& y) {}
+
+#endif