PAPI_mix_hl_ll.c

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/*****************************************************************************
 * This example compares the measurement of IPC using the high-level API     *
 * and the low-level API. Both methods should deliver the same               *
 * result for IPC.                                                           *
 * Note: There is no need to initialize PAPI for the low-level functions     *
 * since this is done by the high-level API.                                 *
 *                                                                           *
 * Hint: Use PAPI's high-level output script to print the measurement report *
 * of the high-level API.                                                    *
 *                                                                           *
 * ../high-level/scripts/papi_hl_output_writer.py --type=accumulate          *
 *****************************************************************************/
 
 
#include <stdio.h>
#include <stdlib.h>
#include "papi.h"
 
#define THRESHOLD 10000
#define ERROR_RETURN(retval) { fprintf(stderr, "Error %d %s:line %d: \n", retval,__FILE__,__LINE__);  exit(retval); }
 
int your_slow_code();
 
int main()
{ 
  float ipc;
  int retval;
  int EventSet = PAPI_NULL;
  long_long values[2];
 
  if ( (retval = PAPI_hl_region_begin("slow_code")) < PAPI_OK )
    ERROR_RETURN(retval);
 
   your_slow_code();
 
  if ( (retval = PAPI_hl_region_end("slow_code")) < PAPI_OK )
    ERROR_RETURN(retval);
 
  if ( (retval = PAPI_hl_stop()) < PAPI_OK )
    ERROR_RETURN(retval);
 
  /* get IPC using low-level API */
  if ( (retval = PAPI_create_eventset(&EventSet)) < PAPI_OK )
    ERROR_RETURN(retval);
  
  if ( (retval = PAPI_add_event(EventSet, PAPI_TOT_INS)) < PAPI_OK )
    ERROR_RETURN(retval);
  if ( (retval = PAPI_add_event(EventSet, PAPI_TOT_CYC)) < PAPI_OK )
    ERROR_RETURN(retval);
 
  if ( (retval = PAPI_start(EventSet)) < PAPI_OK )
    ERROR_RETURN(retval);
 
    your_slow_code();
 
  if ( (retval = PAPI_stop(EventSet, values)) < PAPI_OK )
    ERROR_RETURN(retval);
  
  ipc = (float) ((float)values[0] / (float) ( values[1]));
 
  printf("Results from the low-level API:\n");
  printf("IPC: %f\n", ipc);
 
  exit(0);
}
 
int your_slow_code()
{
  int i;
  double  tmp=1.1;
 
  for(i=1; i<2000; i++)
  { 
    tmp=(tmp+100)/i;
  }
  return 0;
}