diff --git a/include/llvm/ADT/NullablePtr.h b/include/llvm/ADT/NullablePtr.h new file mode 100644 index 00000000000..a9c47a138ec --- /dev/null +++ b/include/llvm/ADT/NullablePtr.h @@ -0,0 +1,52 @@ +//===- llvm/ADT/NullablePtr.h - A pointer that allows null ------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines and implements the NullablePtr class. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_ADT_NULLABLE_PTR_H +#define LLVM_ADT_NULLABLE_PTR_H + +#include +#include + +namespace llvm { +/// NullablePtr pointer wrapper - NullablePtr is used for APIs where a +/// potentially-null pointer gets passed around that must be explicitly handled +/// in lots of places. By putting a wrapper around the null pointer, it makes +/// it more likely that the null pointer case will be handled correctly. +template +class NullablePtr { + T *Ptr; +public: + NullablePtr(T *P = 0) : Ptr(P) {} + + bool isNull() const { return Ptr == 0; } + bool isNonNull() const { return Ptr != 0; } + + /// get - Return the pointer if it is non-null. + const T *get() const { + assert(Ptr && "Pointer wasn't checked for null!"); + return Ptr; + } + + /// get - Return the pointer if it is non-null. + T *get() { + assert(Ptr && "Pointer wasn't checked for null!"); + return Ptr; + } + + T *getPtrOrNull() { return Ptr; } + const T *getPtrOrNull() const { return Ptr; } +}; + +} // end namespace llvm + +#endif