Pointer Type Loop Control Variable for C and C++

Pointer Loop Control Variable for C and C++ in OpenMP 3.0

In OpenMP Specification Version 3.0, the control variable of a loop associated with a for directive can be of pointer type. See Section 2.5.1 on p. 38 of the OpenMP 3.0 Specification.

Example (C/C++):

#include <stdio.h>
#include <stdlib.h>
#include <omp.h>

#define SIZE 10

int main(void)
{
  int *buffer, *base, *end, *p;
  int i;

  omp_set_dynamic(0);
  omp_set_num_threads(10);

  buffer = (int *) malloc (SIZE * sizeof (int));
  base = buffer;
  end = &buffer[SIZE];
  i = 0;

  #pragma omp parallel for shared(i, base, end) private(p) ordered
  for (p = base; p < end ; ++p)
    {
      #pragma omp ordered
        {
          *p = i;
          i++;
        }
    }

  for (i = 0; i < SIZE; i++)
    {
      printf ("%d\n", buffer[i]);
    }

  return 0;
}

% cc -xopenmp -xO3  pointer_loop.c
% a.out
0
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OpenMP 3.0 Features in Express 11.08

Pointer Type Loop Control Variable for C and C++

Pointer Loop Control Variable for C and C++ in OpenMP 3.0

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