vtk-m/vtkm/worklet/ZFPDecompress.h

//============================================================================
//  Copyright (c) Kitware, Inc.
//  All rights reserved.
//  See LICENSE.txt for details.
//  This software is distributed WITHOUT ANY WARRANTY; without even
//  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
//  PURPOSE.  See the above copyright notice for more information.
//
//  Copyright 2014 National Technology & Engineering Solutions of Sandia, LLC (NTESS).
//  Copyright 2014 UT-Battelle, LLC.
//  Copyright 2014 Los Alamos National Security.
//
//  Under the terms of Contract DE-NA0003525 with NTESS,
//  the U.S. Government retains certain rights in this software.
//
//  Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
//  Laboratory (LANL), the U.S. Government retains certain rights in
//  this software.
//============================================================================
#ifndef vtk_m_worklet_zfp_decompressor_h
#define vtk_m_worklet_zfp_decompressor_h

#include <vtkm/Math.h>
#include <vtkm/cont/Algorithm.h>
#include <vtkm/cont/ArrayHandle.h>
#include <vtkm/cont/ArrayHandleConstant.h>
#include <vtkm/cont/ArrayHandleCounting.h>
#include <vtkm/cont/AtomicArray.h>
#include <vtkm/cont/Timer.h>
#include <vtkm/cont/testing/MakeTestDataSet.h>
#include <vtkm/worklet/DispatcherMapField.h>

#include <vtkm/worklet/zfp/ZFPDecode3.h>

using ZFPWord = vtkm::UInt64;

#include <stdio.h>

namespace vtkm
{
namespace worklet
{
#if 0
namespace detail
{

  size_t CalcMem3d(const vtkm::Id3 dims,
                   const int bits_per_block)
  {
    const size_t vals_per_block = 64;
    const size_t size = dims[0] * dims[1] * dims[2];
    size_t total_blocks = size / vals_per_block;
    const size_t bits_per_word = sizeof(ZFPWord) * 8;
    const size_t total_bits = bits_per_block * total_blocks;
    const size_t alloc_size = total_bits / bits_per_word;
    return alloc_size * sizeof(ZFPWord);
  }

  class MemTransfer : public vtkm::worklet::WorkletMapField
  {
  public:
    VTKM_CONT
    MemTransfer()
    {
    }
    using ControlSignature = void(FieldIn<>, WholeArrayInOut<>);
    using ExecutionSignature = void(_1, _2);

    template<typename PortalType>
    VTKM_EXEC
    void operator()(const vtkm::Id id,
                    PortalType& outValue) const
    {
      (void) id;
      (void) outValue;
    }
  }; //class MemTransfer

} // namespace detail

template<typename T>
T *
GetVTKMPointer(vtkm::cont::ArrayHandle<T> &handle)
{
  typedef typename vtkm::cont::ArrayHandle<T> HandleType;
  typedef typename HandleType::template ExecutionTypes<vtkm::cont::DeviceAdapterTagSerial>::Portal PortalType;
  typedef typename vtkm::cont::ArrayPortalToIterators<PortalType>::IteratorType IteratorType;
  IteratorType iter = vtkm::cont::ArrayPortalToIterators<PortalType>(handle.GetPortalControl()).GetBegin();
  return &(*iter);
}

template<typename T>
void
DataDump(vtkm::cont::ArrayHandle<T> handle, std::string fileName)
{

  T *ptr = GetVTKMPointer(handle);
  vtkm::Id osize = handle.GetNumberOfValues();
  FILE *fp = fopen(fileName.c_str(), "wb");;
  if(fp != NULL)
  {
    fwrite(ptr, sizeof(T), osize, fp);
  }

  fclose(fp);
}
#endif

class ZFPDecompressor
{
public:
  template <typename Scalar>
  void Decompress(const vtkm::cont::ArrayHandle<vtkm::Int64>& encodedData,
                  vtkm::cont::ArrayHandle<Scalar>& output,
                  const vtkm::Float64 requestedRate,
                  vtkm::Id3 dims)
  {
    //DataDump(data, "uncompressed");
    zfp::ZFPStream stream;
    const vtkm::Int32 topoDims = 3;
    ;
    vtkm::Float64 actualRate = stream.SetRate(requestedRate, topoDims, vtkm::Float64());

    std::cout << "ArraySize " << encodedData.GetNumberOfValues() << "\n";
    std::cout << "Array dims " << dims << "\n";
    std::cout << "requested rate " << requestedRate << " actual rate " << actualRate << "\n";
    std::cout << "MinBits " << stream.minbits << "\n";

    // Check to see if we need to increase the block sizes
    // in the case where dim[x] is not a multiple of 4

    vtkm::Id3 paddedDims = dims;
    // ensure that we have block sizes
    // that are a multiple of 4
    if (paddedDims[0] % 4 != 0)
      paddedDims[0] += 4 - dims[0] % 4;
    if (paddedDims[1] % 4 != 0)
      paddedDims[1] += 4 - dims[1] % 4;
    if (paddedDims[2] % 4 != 0)
      paddedDims[2] += 4 - dims[2] % 4;
    const vtkm::Id four = 4;
    vtkm::Id totalBlocks =
      (paddedDims[0] / four) * (paddedDims[1] / (four) * (paddedDims[2] / four));

    std::cout << "Padded dims " << paddedDims << "\n";

    size_t outbits = detail::CalcMem3d(paddedDims, stream.minbits);
    std::cout << "Total output bits " << outbits << "\n";
    vtkm::Id outsize = outbits / sizeof(ZFPWord);
    std::cout << "Output size " << outsize << "\n";

    output.Allocate(dims[0] * dims[1] * dims[2]);
    // hopefully this inits/allocates the mem only on the device
    //
    //vtkm::cont::ArrayHandleConstant<vtkm::Int64> zero(0, outsize);
    //vtkm::cont::Algorithm::Copy(zero, output);
    //
    using Timer = vtkm::cont::Timer<vtkm::cont::DeviceAdapterTagSerial>;
    {
      Timer timer;
      vtkm::cont::ArrayHandleCounting<vtkm::Id> one(0, 1, 1);
      vtkm::worklet::DispatcherMapField<detail::MemTransfer> dis;
      dis.Invoke(one, output);
      dis.Invoke(one, encodedData);

      vtkm::Float64 time = timer.GetElapsedTime();
      std::cout << "Copy scalars " << time << "\n";
    }

    // launch 1 thread per zfp block
    vtkm::cont::ArrayHandleCounting<vtkm::Id> blockCounter(0, 1, totalBlocks);

    Timer timer;
    vtkm::worklet::DispatcherMapField<zfp::Decode3> decompressDispatcher(
      zfp::Decode3(dims, paddedDims, stream.maxbits));
    decompressDispatcher.Invoke(blockCounter, output, encodedData);

    vtkm::Float64 time = timer.GetElapsedTime();
    size_t total_bytes = output.GetNumberOfValues() * sizeof(vtkm::Float64);
    vtkm::Float64 gB = vtkm::Float64(total_bytes) / (1024. * 1024. * 1024.);
    vtkm::Float64 rate = gB / time;
    std::cout << "Decompress time " << time << " sec\n";
    std::cout << "Decompress rate " << rate << " GB / sec\n";
    DataDump(output, "compressed");
  }
};
} // namespace worklet
} // namespace vtkm
#endif //  vtk_m_worklet_zfp_compressor_h