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#include <immintrin.h>
#include <stdlib.h>
#include <iostream>
#include "asterics_hpc.h"
#define CMP_LOWER_THAN 1
#define CMP_GREATER_EQUAL_THAN 4
using namespace std;
///Get a random number between 0 and 1
/** @return random number between 0 and 1
*/
float randFloat(){
return ((float)rand())/((float)RAND_MAX);
}
///Do the dummy copy
/** @param[out] tabResult : table of results of tabX*tabY
* @param tabX : input table
* @param tabY : input table
* @param tabProba : table of probability
* @param nbElement : number of elements in the tables
* @param proba : probability to copy tabX in tabResult
*/
void dummyCopy(float* tabResult, const float * tabX, const float* tabY,
const float * tabProba, long unsigned int nbElement, float proba)
{
long unsigned int vecSize(VECTOR_ALIGNEMENT/sizeof(float));
long unsigned int nbVec(nbElement/vecSize);
register __m256 vecThres = _mm256_broadcast_ss(&proba);
for(long unsigned int i(0lu); i < nbVec; ++i){
__m256 vecProb = _mm256_load_ps(tabProba + i*vecSize);
__m256i vecX = (__m256i)_mm256_load_ps(tabX + i*vecSize);
__m256i vecCondLower = (__m256i)_mm256_cmp_ps(vecProb, vecThres, CMP_LOWER_THAN); register __m256i vecAndLower = _mm256_and_si256(vecX, vecCondLower);
__m256i vecY = (__m256i)_mm256_load_ps(tabY + i*vecSize);
__m256i vecCondGreater = (__m256i)_mm256_cmp_ps(vecProb, vecThres, CMP_GREATER_EQUAL_THAN); __m256i vecAndGreater = _mm256_and_si256(vecY, vecCondGreater);
__m256 vecRes = (__m256)_mm256_or_si256(vecAndLower, vecAndGreater);
_mm256_store_ps(tabResult + i*vecSize, vecRes);
}
}
///Get the number of cycles per elements of the saxpy
/** @param proba : probability to copy a value in the table X
* @param nbRepetition : number of repetition to evaluate the function saxpy
*/
void evaluateDummyCopy(float proba, long unsigned int nbRepetition){
long unsigned int nbElement(10000lu);
float * tabResult = (float*)asterics_malloc(sizeof(float)*nbElement);
float * tabX = (float*)asterics_malloc(sizeof(float)*nbElement);
float * tabY = (float*)asterics_malloc(sizeof(float)*nbElement);
float * tabProba = (float*)asterics_malloc(sizeof(float)*nbElement);
for(long unsigned int i(0lu); i < nbElement; ++i){
tabX[i] = (float)(i*32lu%17lu);
tabY[i] = (float)(i*57lu%31lu);
tabProba[i] = randFloat();
}
long unsigned int beginTime(rdtsc());
for(long unsigned int i(0lu); i < nbRepetition; ++i){
dummyCopy(tabResult, tabX, tabY, tabProba, nbElement, proba);
}
long unsigned int elapsedTime((double)(rdtsc() - beginTime)/((double)nbRepetition));
double cyclePerElement(((double)elapsedTime)/((double)nbElement));
cout << "evaluateDummyCopy : proba = "<<proba<<", nbElement = "<<nbElement
<<", cyclePerElement = " << cyclePerElement << " cy/el, elapsedTime = " << elapsedTime << " cy" << endl;
cerr << proba << "\t" << cyclePerElement << "\t" << elapsedTime << endl;
asterics_free(tabProba);
asterics_free(tabResult);
asterics_free(tabX);
asterics_free(tabY);
}
int main(int argc, char** argv){
cout << "Branching probability no branching" << endl;
evaluateDummyCopy(0.1f, 100000lu);
evaluateDummyCopy(0.2f, 100000lu);
evaluateDummyCopy(0.3f, 100000lu);
evaluateDummyCopy(0.4f, 100000lu);
evaluateDummyCopy(0.5f, 100000lu);
evaluateDummyCopy(0.6f, 100000lu);
evaluateDummyCopy(0.7f, 100000lu);
evaluateDummyCopy(0.8f, 100000lu);
evaluateDummyCopy(0.9f, 100000lu);
return 0;
}
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