allocators.h

Go to the documentation of this file.

#ifndef NPSTAT_ALLOCATORS_HH_
#define NPSTAT_ALLOCATORS_HH_

#include <cassert>

namespace npstat {
  template <typename T>
  inline T* makeBuffer(unsigned sizeNeeded, T* stackBuffer, unsigned sizeofStackBuffer) {
    if (sizeNeeded > sizeofStackBuffer || stackBuffer == nullptr)
      return new T[sizeNeeded];
    else
      return stackBuffer;
  }

  template <typename T>
  inline void destroyBuffer(T* thisBuffer, const T* stackBuffer) {
    if (thisBuffer != stackBuffer)
      delete[] thisBuffer;
  }

  template <typename T1, typename T2>
  inline void copyBuffer(T1* dest, const T2* source, const unsigned long len) {
    if (len) {
      assert(dest);
      assert(source);
      for (unsigned long i = 0; i < len; ++i)
        *dest++ = static_cast<T1>(*source++);
    }
  }

  template <typename T1, typename T2>
  inline void transposeBuffer(T1* dest, const T2* source, const unsigned long dim) {
    if (dim) {
      assert(dest);
      assert(source);
      for (unsigned long i = 0; i < dim; ++i) {
        for (unsigned long j = 0; j < dim; ++j)
          dest[j * dim] = static_cast<T1>(*source++);
        ++dest;
      }
    }
  }

  template <typename T1, typename T2>
  inline void transposeBuffer(T1* dest, const T2* source, const unsigned long M, const unsigned long N) {
    if (M && N) {
      assert(dest);
      assert(source);
      for (unsigned long i = 0; i < M; ++i) {
        for (unsigned long j = 0; j < N; ++j)
          dest[j * M] = static_cast<T1>(*source++);
        ++dest;
      }
    }
  }

  template <typename T>
  inline void clearBuffer(T* buf, const unsigned long len) {
    if (len) {
      assert(buf);
      const T zero = T();
      for (unsigned long i = 0; i < len; ++i)
        *buf++ = zero;
    }
  }
}  // namespace npstat

#endif  // NPSTAT_ALLOCATORS_HH_