examples/addition.c

// Copyright (c) 2017 Facebook Inc.
// Copyright (c) 2015-2017 Georgia Institute of Technology
// All rights reserved.
//
// Copyright 2019 Google LLC
//
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree.

#include <assert.h>
#include <stdint.h>
#include <stdio.h>

#include <pthreadpool.h>

struct array_addition_context {
  double *augend;
  double *addend;
  double *sum;
};

static void add_arrays(struct array_addition_context *context, size_t i) {
  context->sum[i] = context->augend[i] + context->addend[i];
}

#define ARRAY_SIZE 4

int main() {
  double augend[ARRAY_SIZE] = {1.0, 2.0, 4.0, -5.0};
  double addend[ARRAY_SIZE] = {0.25, -1.75, 0.0, 0.5};
  double sum[ARRAY_SIZE];

  pthreadpool_t threadpool = pthreadpool_create(0);
  assert(threadpool != NULL);

  const size_t threads_count = pthreadpool_get_threads_count(threadpool);
  printf("Created thread pool with %zu threads\n", threads_count);

  struct array_addition_context context = {augend, addend, sum};
  pthreadpool_parallelize_1d(threadpool, (pthreadpool_task_1d_t)add_arrays,
                             (void **)&context, ARRAY_SIZE,
                             PTHREADPOOL_FLAG_DISABLE_DENORMALS /* flags */);

  pthreadpool_destroy(threadpool);
  threadpool = NULL;

  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Augend", augend[0], augend[1],
         augend[2], augend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Addend", addend[0], addend[1],
         addend[2], addend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Sum", sum[0], sum[1], sum[2],
         sum[3]);

  return 0;
}