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/* StarPU --- Runtime system for heterogeneous multicore architectures.
*
* Copyright (C) 2012 Institut National de Recherche en Informatique et Automatique
*
* StarPU is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* StarPU is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* See the GNU Lesser General Public License in COPYING.LGPL for more details.
*/
/* This example showcases features of the StarPU GCC plug-in. It defines a
"vector scaling" task with multiple CPU implementations, an OpenCL
implementation, and a CUDA implementation.
Compiling it without `-fplugin=starpu.so' yields valid sequential code. */
#include <math.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
/* Declare and define the standard CPU implementation. */
static void vector_scal (unsigned int size, float vector[size], float factor)
__attribute__ ((task));
/* The CPU implementation. */
static void
vector_scal (unsigned int size, float vector[size], float factor)
{
unsigned int i;
for (i = 0; i < size; i++)
vector[i] *= factor;
}
#if defined STARPU_GCC_PLUGIN && defined __SSE__
/* The SSE-capable CPU implementation. */
#include <xmmintrin.h>
static void vector_scal_sse (unsigned int size, float vector[size], float factor)
__attribute__ ((task_implementation ("cpu", vector_scal)));
static void
vector_scal_sse (unsigned int size, float vector[size], float factor)
{
unsigned int n_iterations = size / 4;
__m128 *VECTOR = (__m128 *) vector;
__m128 _FACTOR __attribute__ ((aligned (16)));
_FACTOR = _mm_set1_ps (factor);
unsigned int i;
for (i = 0; i < n_iterations; i++)
VECTOR[i] = _mm_mul_ps (_FACTOR, VECTOR[i]);
unsigned int remainder = size % 4;
if (remainder != 0)
{
unsigned int start = 4 * n_iterations;
for (i = start; i < start + remainder; ++i)
vector[i] = factor * vector[i];
}
}
#endif /* __SSE__ */
/* Declaration and definition of the OpenCL implementation. */
#if defined STARPU_GCC_PLUGIN && defined STARPU_USE_OPENCL
#include <starpu_opencl.h>
/* The OpenCL programs, loaded from `main'. */
static struct starpu_opencl_program cl_programs;
static void vector_scal_opencl (unsigned int size, float vector[size], float factor)
__attribute__ ((task_implementation ("opencl", vector_scal)));
static void
vector_scal_opencl (unsigned int size, float vector[size], float factor)
{
int id, devid, err;
cl_kernel kernel;
cl_command_queue queue;
cl_event event;
cl_mem val = (cl_mem) vector;
id = starpu_worker_get_id ();
devid = starpu_worker_get_devid (id);
/* Prepare to invoke the kernel. In the future, this will be largely
automated. */
err = starpu_opencl_load_kernel (&kernel, &queue, &cl_programs,
"vector_mult_opencl", devid);
if (err != CL_SUCCESS)
STARPU_OPENCL_REPORT_ERROR (err);
err = clSetKernelArg (kernel, 0, sizeof (val), &val);
err |= clSetKernelArg (kernel, 1, sizeof (size), &size);
err |= clSetKernelArg (kernel, 2, sizeof (factor), &factor);
if (err)
STARPU_OPENCL_REPORT_ERROR (err);
size_t global = size, local = 1;
err = clEnqueueNDRangeKernel (queue, kernel, 1, NULL, &global, &local, 0,
NULL, &event);
if (err != CL_SUCCESS)
STARPU_OPENCL_REPORT_ERROR (err);
clFinish (queue);
starpu_opencl_collect_stats (event);
clReleaseEvent (event);
starpu_opencl_release_kernel (kernel);
}
#endif
#ifdef STARPU_USE_CUDA
/* Declaration of the CUDA implementation. The definition itself is in the
`.cu' file itself. */
extern void vector_scal_cuda (unsigned int size, float vector[size], float factor)
__attribute__ ((task_implementation ("cuda", vector_scal)));
#endif
#define EPSILON 1e-3
static bool
check (size_t size, float vector[size], float factor)
{
size_t i;
for (i = 0; i < size; i++)
{
if (fabs(vector[i] - i * factor) > i*factor*EPSILON)
{
fprintf(stderr, "%.2f != %.2f\n", vector[i], i*factor);
return false;
}
}
return true;
}
int
main (void)
{
bool valid;
#pragma starpu initialize
#if defined STARPU_GCC_PLUGIN && defined STARPU_USE_OPENCL
starpu_opencl_load_opencl_from_file ("vector_scal_opencl_kernel.cl",
&cl_programs, "");
#endif
#define NX 0x100000
#define FACTOR 3.14
{
float vector[NX] __attribute__ ((heap_allocated));
#pragma starpu register vector
size_t i;
for (i = 0; i < NX; i++)
vector[i] = (float) i;
vector_scal (NX, vector, FACTOR);
#pragma starpu wait
#pragma starpu unregister vector
valid = check (NX, vector, FACTOR);
} /* VECTOR is automatically freed here. */
#pragma starpu shutdown
return valid ? EXIT_SUCCESS : EXIT_FAILURE;
}
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