cuda-samples/Samples/0_Introduction/cppIntegration/main.cpp

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/*
 * Example of integrating CUDA functions into an existing
 * application / framework.
 * CPP code representing the existing application / framework.
 * Compiled with default CPP compiler.
 */

// includes, system
#include <iostream>
#include <stdlib.h>

// Required to include CUDA vector types
#include <cuda_runtime.h>
#include <vector_types.h>
#include <helper_cuda.h>

////////////////////////////////////////////////////////////////////////////////
// declaration, forward
extern "C" bool runTest(const int argc, const char **argv, char *data,
                        int2 *data_int2, unsigned int len);

////////////////////////////////////////////////////////////////////////////////
// Program main
////////////////////////////////////////////////////////////////////////////////
int main(int argc, char **argv) {
  // input data
  int len = 16;
  // the data has some zero padding at the end so that the size is a multiple of
  // four, this simplifies the processing as each thread can process four
  // elements (which is necessary to avoid bank conflicts) but no branching is
  // necessary to avoid out of bounds reads
  char str[] = {82,  111, 118, 118, 121, 42, 97, 121,
                124, 118, 110, 56,  10,  10, 10, 10};

  // Use int2 showing that CUDA vector types can be used in cpp code
  int2 i2[16];

  for (int i = 0; i < len; i++) {
    i2[i].x = str[i];
    i2[i].y = 10;
  }

  bool bTestResult;

  // run the device part of the program
  bTestResult = runTest(argc, (const char **)argv, str, i2, len);

  std::cout << str << std::endl;

  char str_device[16];

  for (int i = 0; i < len; i++) {
    str_device[i] = (char)(i2[i].x);
  }

  std::cout << str_device << std::endl;

  exit(bTestResult ? EXIT_SUCCESS : EXIT_FAILURE);
}