Centre Blaise Pascal » Bench4GPU

/******************************************************************************

* FILE: hello.c

* DESCRIPTION:

*   A "hello world" Pthreads program.  Demonstrates thread creation and

*   termination.

* AUTHOR: Blaise Barney

* LAST REVISED: 08/09/11

******************************************************************************/

#include <pthread.h>

#include <stdio.h>

#include <stdlib.h>

#define NUM_THREADS        4

#include <math.h>

#include <stdio.h>

// Marsaglia RNG very simple implementation

#define znew  ((z=36969*(z&65535)+(z>>16))<<16)

#define wnew  ((w=18000*(w&65535)+(w>>16))&65535)

#define MWC   (znew+wnew)

#define SHR3  (jsr=(jsr=(jsr=jsr^(jsr<<17))^(jsr>>13))^(jsr<<5))

#define CONG  (jcong=69069*jcong+1234567)

#define KISS  ((MWC^CONG)+SHR3)

#define MWCfp MWC * 2.328306435454494e-10f

#define KISSfp KISS * 2.328306435454494e-10f

#define ITERATIONS 1000000000

int MainLoopGlobal(unsigned int iterations,unsigned int seed_w,unsigned int seed_z)

{

   unsigned int z=seed_z;

   unsigned int w=seed_w;

   int total=0;

   for (unsigned int i=0;i<iterations;i++) {

      float x=MWCfp ;

      float y=MWCfp ;

      // Matching test

      int inside=((x*x+y*y) < 1.0f) ? 1:0;

      total+=inside;

   }

   return(total);

}

void *PrintHello(void *threadid)

{

   long tid;

   tid = (long)threadid;

   printf("Hello World! It's me, thread #%ld!\n", tid);

   pthread_exit(NULL);

}

void *MainLoopThread(void *threadid)

{

   long tid;

   tid = (long)threadid;

   printf("Hello World! It's me, thread #%ld!\n", tid);

   /* unsigned int z=seed_z; */

   /* unsigned int w=seed_w; */

   unsigned int z=16;

   unsigned int w=64;

   int total=0;

   for (unsigned int i=0;i<ITERATIONS;i++) {

      float x=MWCfp ;

      float y=MWCfp ;

      // Matching test

      int inside=((x*x+y*y) < 1.0f) ? 1:0;

      total+=inside;

   }

   printf("In #%ld, found %i inside\n",tid,total);

   pthread_exit(NULL);

}

int main(int argc, char *argv[])

{

   pthread_t threads[NUM_THREADS];

   int rc;

   long t;

   for(t=0;t<NUM_THREADS;t++){

     printf("In main: creating thread %ld\n", t);

     rc = pthread_create(&threads[t], NULL, MainLoopThread, (void *)t);

     if (rc){

       printf("ERROR; return code from pthread_create() is %d\n", rc);

       exit(-1);

       }

     }

   /* Last thing that main() should do */

   pthread_exit(NULL);

}