ComputeNonbondedInl.h File Reference

#include "ComputeNonbondedUtil.h"
#include "SimParameters.h"
#include "Molecule.h"
#include "LJTable.h"
#include "ReductionMgr.h"
#include "ReserveArray.h"
#include "PressureProfile.h"
#include "Random.h"
#include <algorithm>

Go to the source code of this file.

Macros
#define	restrict
#define	NBPAIR   1
#define	NBSELF   2
#define	__TERNARY_ASSIGN(test, val0, val1)   ((test * val0) + ((1 - test) * val1))

Functions
int	pairlist_from_pairlist (BigReal cutoff2, BigReal p_i_x, BigReal p_i_y, BigReal p_i_z, const CompAtom *p_j, const plint *list, int list_size, int *newlist, BigReal r2_delta, BigReal *r2list)
void	sortEntries_selectionSort (SortEntry *const se, const int seLen)
void	sortEntries_bubbleSort (SortEntry *const se, const int seLen)
void	sortEntries_mergeSort_v1 (SortEntry *&se, SortEntry *&buf, int seLen)
void	sortEntries_mergeSort_v2 (SortEntry *&se, SortEntry *&buf, int seLen)

Macro Definition Documentation

__TERNARY_ASSIGN

#define __TERNARY_ASSIGN	(		test,
			val0,
			val1
	)		((test * val0) + ((1 - test) * val1))

Referenced by sortEntries_mergeSort_v2().

NBPAIR

#define NBPAIR   1

Definition at line 346 of file ComputeNonbondedInl.h.

NBSELF

#define NBSELF   2

Definition at line 347 of file ComputeNonbondedInl.h.

restrict

#define restrict

Copyright (c) 1995, 1996, 1997, 1998, 1999, 2000 by The Board of Trustees of the University of Illinois. All rights reserved.

Definition at line 15 of file ComputeNonbondedInl.h.

Function Documentation

pairlist_from_pairlist()

int pairlist_from_pairlist ( BigReal  cutoff2, BigReal  p_i_x, BigReal  p_i_y, BigReal  p_i_z, const CompAtom *  p_j, const plint *  list, int  list_size, int *  newlist, BigReal  r2_delta, BigReal *  r2list  )

inline

Definition at line 80 of file ComputeNonbondedInl.h.

References p_j.

                                                                     {
  
  BigReal cutoff2_delta = cutoff2 + r2_delta;
  int *nli = newlist;
  BigReal *r2i = r2list;

  if ( list_size <= 0) return 0;

  int g = 0;

#ifdef NAMD_KNL

  BigReal p_j_x, p_j_y, p_j_z;
  BigReal x2, y2, z2, r2;
#pragma vector aligned
#pragma ivdep
  for ( g = 0 ; g < list_size; ++g ) {
    int gi=list[g];
    p_j_x = p_j[ gi ].position.x;
    p_j_y = p_j[ gi ].position.y;
    p_j_z = p_j[ gi ].position.z;

    x2 = p_i_x - p_j_x;
    r2 = x2 * x2 + r2_delta;
    y2 = p_i_y - p_j_y;
    r2 += y2 * y2;
    z2 = p_i_z - p_j_z;
    r2 += z2 * z2;

    if ( r2 <= cutoff2_delta ) {
      *nli = gi;  ++nli;
      *r2i = r2;  ++r2i;
    }
  }

#else // NAMD_KNL
#ifndef SIMPLE_PAIRLIST
#ifdef  A2_QPX
  //***************************************************************
  //* 4-way unrolled and software-pipelined and optiized via QPX
  //***************************************************************  

  int jout = 0;
  if ( list_size > 16) {
    // prefetch
    int jcur0 = list[g];
    int jcur1 = list[g + 1];
    int jcur2 = list[g + 2];
    int jcur3 = list[g + 3];
    
    int j0, j1, j2, j3;
    
    vector4double    pj_v_0, pj_v_1, pj_v_2, pj_v_3; 
    vector4double    v_0, v_1, v_2, v_3;
    register BigReal r2_0, r2_1, r2_2, r2_3;
    
    vector4double p_i_v = {p_i_x, p_i_y, p_i_z, 0.};
    vector4double r2_delta_v = {r2_delta};

    pj_v_0 = vec_ld(jcur0 * sizeof(CompAtom), (BigReal *)p_j);
    pj_v_1 = vec_ld(jcur1 * sizeof(CompAtom), (BigReal *)p_j);  
    pj_v_2 = vec_ld(jcur2 * sizeof(CompAtom), (BigReal *)p_j);  
    pj_v_3 = vec_ld(jcur3 * sizeof(CompAtom), (BigReal *)p_j);  
    
    for ( g = 4 ; g < list_size - 4; g += 4 ) {
      // compute 1d distance, 4-way parallel      
      //Save the previous iterations values, gives more flexibility 
      //to the compiler to schedule the loads and the computation
      j0   =   jcur0;           j1   =   jcur1;
      j2   =   jcur2;           j3   =   jcur3;
      
      jcur0  =  list[g    ];    jcur1  =  list[g + 1];
      jcur2  =  list[g + 2];    jcur3  =  list[g + 3];

      __dcbt((void*)(p_j + jcur0));

      v_0 = vec_sub (p_i_v, pj_v_0);
      v_1 = vec_sub (p_i_v, pj_v_1);
      v_2 = vec_sub (p_i_v, pj_v_2);
      v_3 = vec_sub (p_i_v, pj_v_3);
      
      v_0 = vec_madd (v_0, v_0, r2_delta_v);
      v_1 = vec_madd (v_1, v_1, r2_delta_v);
      v_2 = vec_madd (v_2, v_2, r2_delta_v);
      v_3 = vec_madd (v_3, v_3, r2_delta_v);

      pj_v_0 = vec_ld(jcur0 * sizeof(CompAtom), (BigReal *)p_j);
      pj_v_1 = vec_ld(jcur1 * sizeof(CompAtom), (BigReal *)p_j);  
      pj_v_2 = vec_ld(jcur2 * sizeof(CompAtom), (BigReal *)p_j);  
      pj_v_3 = vec_ld(jcur3 * sizeof(CompAtom), (BigReal *)p_j);  

      r2_0 = vec_extract(v_0, 0) + vec_extract(v_0, 1) + vec_extract(v_0, 2);
      r2_1 = vec_extract(v_1, 0) + vec_extract(v_1, 1) + vec_extract(v_1, 2);
      r2_2 = vec_extract(v_2, 0) + vec_extract(v_2, 1) + vec_extract(v_2, 2);
      r2_3 = vec_extract(v_3, 0) + vec_extract(v_3, 1) + vec_extract(v_3, 2);
      
      size_t test0, test1, test2, test3;
      size_t jout0, jout1, jout2, jout3;
      
      test0 = ( r2_0   <   cutoff2_delta );
      test1 = ( r2_1   <   cutoff2_delta );
      test2 = ( r2_2   <   cutoff2_delta );
      test3 = ( r2_3   <   cutoff2_delta );
      
      jout0 = jout;
      nli[ jout0 ]  = j0;         r2i[ jout0 ] = r2_0;
      jout += test0;              jout1 = jout;

      nli[ jout1 ]  = j1;         r2i[ jout1 ] = r2_1;
      jout += test1;              jout2 = jout;

      nli[ jout2 ]  = j2;         r2i[ jout2 ] = r2_2;
      jout += test2;              jout3 = jout;

      nli[ jout3 ]  = j3;         r2i[ jout3 ] = r2_3;
      jout += test3;
    }
    g -= 4;
  }

  nli += jout;
  r2i += jout;  
#else
  //***************************************************************
  //* 4-way unrolled and software-pipelined 
  //***************************************************************

  int jout = 0;
  if ( list_size > 16) {
    // prefetch
    int jcur0 = list[g];
    int jcur1 = list[g + 1];
    int jcur2 = list[g + 2];
    int jcur3 = list[g + 3];
    
    int j0, j1, j2, j3;
    
    register  BigReal pj_x_0, pj_x_1, pj_x_2, pj_x_3; 
    register  BigReal pj_y_0, pj_y_1, pj_y_2, pj_y_3; 
    register  BigReal pj_z_0, pj_z_1, pj_z_2, pj_z_3; 
    
    register BigReal t_0, t_1, t_2, t_3, r2_0, r2_1, r2_2, r2_3;
    
    pj_x_0 = p_j[jcur0].position.x;
    pj_x_1 = p_j[jcur1].position.x;  
    pj_x_2 = p_j[jcur2].position.x;  
    pj_x_3 = p_j[jcur3].position.x;  
    pj_y_0 = p_j[jcur0].position.y; 
    pj_y_1 = p_j[jcur1].position.y;  
    pj_y_2 = p_j[jcur2].position.y;  
    pj_y_3 = p_j[jcur3].position.y;  
    pj_z_0 = p_j[jcur0].position.z; 
    pj_z_1 = p_j[jcur1].position.z;
    pj_z_2 = p_j[jcur2].position.z; 
    pj_z_3 = p_j[jcur3].position.z;
    
    for ( g = 4 ; g < list_size - 4; g += 4 ) {
      // compute 1d distance, 4-way parallel
      
      //Save the previous iterations values, gives more flexibility 
      //to the compiler to schedule the loads and the computation
      j0   =   jcur0;           j1   =   jcur1;
      j2   =   jcur2;           j3   =   jcur3;
      
      jcur0  =  list[g    ];    jcur1  =  list[g + 1];
      jcur2  =  list[g + 2];    jcur3  =  list[g + 3];

#ifdef ARCH_POWERPC
      __dcbt ((void *) &p_j[jcur0]);
#endif      

      //Compute X distance
      t_0   =  p_i_x - pj_x_0;   t_1   =  p_i_x - pj_x_1;
      t_2   =  p_i_x - pj_x_2;   t_3   =  p_i_x - pj_x_3;
      
      r2_0  =  t_0 * t_0 + r2_delta; 
      r2_1  =  t_1 * t_1 + r2_delta;
      r2_2  =  t_2 * t_2 + r2_delta;
      r2_3  =  t_3 * t_3 + r2_delta;
      
      //Compute y distance
      t_0    =  p_i_y - pj_y_0;   t_1    =  p_i_y - pj_y_1;
      t_2    =  p_i_y - pj_y_2;   t_3    =  p_i_y - pj_y_3;
      r2_0  +=  t_0 * t_0;        r2_1  +=  t_1 * t_1;
      r2_2  +=  t_2 * t_2;        r2_3  +=  t_3 * t_3;
      
      //compute z distance
      t_0    =  p_i_z - pj_z_0;   t_1    =  p_i_z - pj_z_1;
      t_2    =  p_i_z - pj_z_2;   t_3    =  p_i_z - pj_z_3;
      r2_0  +=  t_0 * t_0;        r2_1  +=  t_1 * t_1;
      r2_2  +=  t_2 * t_2;        r2_3  +=  t_3 * t_3;
      
      pj_x_0 = p_j[jcur0].position.x;
      pj_x_1 = p_j[jcur1].position.x;  
      pj_x_2 = p_j[jcur2].position.x;  
      pj_x_3 = p_j[jcur3].position.x;  
      pj_y_0 = p_j[jcur0].position.y; 
      pj_y_1 = p_j[jcur1].position.y;  
      pj_y_2 = p_j[jcur2].position.y;  
      pj_y_3 = p_j[jcur3].position.y;  
      pj_z_0 = p_j[jcur0].position.z; 
      pj_z_1 = p_j[jcur1].position.z;
      pj_z_2 = p_j[jcur2].position.z; 
      pj_z_3 = p_j[jcur3].position.z;
      
      bool test0, test1, test2, test3;
      
      test0 = ( r2_0   <   cutoff2_delta );
      test1 = ( r2_1   <   cutoff2_delta );
      test2 = ( r2_2   <   cutoff2_delta );
      test3 = ( r2_3   <   cutoff2_delta );
      
      int jout0, jout1, jout2, jout3;

      jout0 = jout;
      nli[ jout0 ]  = j0;         r2i[ jout0 ] = r2_0;
      jout += test0;              jout1 = jout;
      nli[ jout1 ]  = j1;         r2i[ jout1 ] = r2_1;
      jout += test1;              jout2 = jout;
      nli[ jout2 ]  = j2;         r2i[ jout2 ] = r2_2;
      jout += test2;              jout3 = jout;
      nli[ jout3 ]  = j3;         r2i[ jout3 ] = r2_3;

      jout += test3;
    }
    g -= 4;
  }

  nli += jout;
  r2i += jout;  
#endif
#endif

  int j2 = list[g];
  BigReal p_j_x = p_j[j2].position.x;
  BigReal p_j_y = p_j[j2].position.y;
  BigReal p_j_z = p_j[j2].position.z;
  while ( g < list_size ) {
    int j = j2;
    j2 = list[++g];
    BigReal t2 = p_i_x - p_j_x;
    BigReal r2 = t2 * t2 + r2_delta;
    p_j_x = p_j[j2].position.x;
    t2 = p_i_y - p_j_y;
    r2 += t2 * t2;
    p_j_y = p_j[j2].position.y;
    t2 = p_i_z - p_j_z;
    r2 += t2 * t2;
    p_j_z = p_j[j2].position.z;
    if ( r2 <= cutoff2_delta ) {
      *nli= j; ++nli;
      *r2i = r2; ++r2i;
    }
  }

#endif // NAMD_KNL

  return nli - newlist;
}

sortEntries_bubbleSort()

void sortEntries_bubbleSort ( SortEntry *const  se, const int  seLen  )

inline

Definition at line 388 of file ComputeNonbondedInl.h.

References __sort_entry::index, and __sort_entry::sortValue.

                                                                          {

  register int keepSorting = 0;

  do {

    // Reset the keepSorting flag (assume no swaps will occur)
    keepSorting = 0;

    // Loop through the pairs and swap if needed
    register SortEntry* sortEntry1 = se;
    for (int i = 1; i < seLen; i++) {

      register SortEntry* sortEntry0 = sortEntry1;
      sortEntry1 = se + i;
      register BigReal sortEntry0_sortValue = sortEntry0->sortValue;
      register BigReal sortEntry1_sortValue = sortEntry1->sortValue;

      if (sortEntry0_sortValue > sortEntry1_sortValue) {
        register int sortEntry0_index = sortEntry0->index;
        register int sortEntry1_index = sortEntry1->index;
        sortEntry0->index = sortEntry1_index;
        sortEntry0->sortValue = sortEntry1_sortValue;
        sortEntry1->index = sortEntry0_index;
        sortEntry1->sortValue = sortEntry0_sortValue;
        keepSorting = 1;
      }
    }

  } while (keepSorting != 0);  // Loop again if at least one set of
                               //   elements was swapped.
}

sortEntries_mergeSort_v1()

void sortEntries_mergeSort_v1 ( SortEntry *&  se, SortEntry *&  buf, int  seLen  )

inline

Setup pointers and counts for sublists in the pair. ///

Merge the sublists ///

Definition at line 425 of file ComputeNonbondedInl.h.

References __sort_entry::index, and __sort_entry::sortValue.

                                                                                   {

  register SortEntry* srcArray = se;
  register SortEntry* dstArray = buf;

  // Start with each element being a separate list.  Start
  //   merging the "lists" into larger lists.
  register int subListSize = 1;
  while (subListSize < seLen) {

    // NOTE: This iteration consumes sublists of length
    //   subListSize and produces sublists of length
    //   (2*subListSize).  So, keep looping while the length of a
    //   single sorted sublist is not the size of the entire array.

    // Iterate through the lists, merging each consecutive pair of lists.
    register int firstListOffset = 0;
    while (firstListOffset < seLen) {


      register int numElements = std::min(2 * subListSize, seLen - firstListOffset);
      register int list0len;
      register int list1len;
      if (numElements > subListSize) {
        list0len = subListSize;                // First list full
        list1len = numElements - subListSize;  // 1+ elements in second list
      } else {
        list0len = numElements;                // 1+ elements in first list
        list1len = 0;                          // Zero elements in second list
      }

      register SortEntry* list0ptr = srcArray + firstListOffset;
      register SortEntry* list1ptr = list0ptr + subListSize;
      register SortEntry* dstptr = dstArray + firstListOffset;


      // While there are elements in both lists, pick from one
      while (list0len > 0 && list1len > 0) {

        register BigReal sortValue0 = list0ptr->sortValue;
        register BigReal sortValue1 = list1ptr->sortValue;

        if (sortValue0 < sortValue1) {  // choose first list (list0)

          // Copy the value from srcArray to dstArray
          register int index0 = list0ptr->index;
          dstptr->sortValue = sortValue0;
          dstptr->index = index0;

          // Move the pointers forward for the sublists
          dstptr++;
          list0ptr++;
          list0len--;

        } else {                        // choose second list (list1)

          // Copy the value from srcArray to dstArray
          register int index1 = list1ptr->index;
          dstptr->sortValue = sortValue1;
          dstptr->index = index1;

          // Move the pointers forward for the sublists
          dstptr++;
          list1ptr++;
          list1len--;
        }

      } // end while (list0len > 0 && list1len > 0)

      // NOTE: Either list0len or list1len is zero at this point
      //   so only one of the following loops should execute.

      // Drain remaining elements from the first list (list0)
      while (list0len > 0) {

        // Copy the value from srcArray to dstArray
        register BigReal sortValue0 = list0ptr->sortValue;
        register int index0 = list0ptr->index;
        dstptr->sortValue = sortValue0;
        dstptr->index = index0;

        // Move the pointers forward for the sublists
        dstptr++;
        list0ptr++;
        list0len--;

      } // end while (list0len > 0)

      // Drain remaining elements from the first list (list1)
      while (list1len > 0) {

        // Copy the value from srcArray to dstArray
        register BigReal sortValue1 = list1ptr->sortValue;
        register int index1 = list1ptr->index;
        dstptr->sortValue = sortValue1;
        dstptr->index = index1;

        // Move the pointers forward for the sublists
        dstptr++;
        list1ptr++;
        list1len--;

      } // end while (list1len > 0)

      // Move forward to the next pair of sub-lists
      firstListOffset += (2 * subListSize);

    } // end while (firstListOffset < seLen) {

    // Swap the dstArray and srcArray pointers
    register SortEntry* tmpPtr = dstArray;
    dstArray = srcArray;
    srcArray = tmpPtr;

    // Double the subListSize
    subListSize <<= 1;

  }  // end while (subListSize < seLen)

  // Set the sort values pointers (NOTE: srcArray and dstArray are
  //   swapped at the end of each iteration of the merge sort outer-loop).
  buf = dstArray;
  se = srcArray;
}

sortEntries_mergeSort_v2()

void sortEntries_mergeSort_v2 ( SortEntry *&  se, SortEntry *&  buf, int  seLen  )

inline

Setup pointers and counts for sublists in the pair. ///

Merge the sublists ///

Definition at line 556 of file ComputeNonbondedInl.h.

References __TERNARY_ASSIGN, __sort_entry::index, and __sort_entry::sortValue.

                                                                                   {

  // NOTE: This macro "returns" either val0 (if test == 0) or val1 (if
  // test == 1).  It expects test to be either 0 or 1 (no other values).
  #define __TERNARY_ASSIGN(test, val0, val1)   ((test * val0) + ((1 - test) * val1))

  register SortEntry* srcArray = se;
  register SortEntry* dstArray = buf;

  // Start with each element being a separate list.  Start
  //   merging the "lists" into larger lists.
  register int subListSize = 1;
  while (subListSize < seLen) {

    // NOTE: This iteration consumes sublists of length
    //   subListSize and produces sublists of length
    //   (2*subListSize).  So, keep looping while the length of a
    //   single sorted sublist is not the size of the entire array.

    // Iterate through the lists, merging each consecutive pair of lists.
    register int firstListOffset = 0;
    while (firstListOffset < seLen) {


      // Calculate the number of elements for both sublists...
      //   min(2 * subListSize, seLen - firstListOffset);
      register int numElements;
      {
        register int numElements_val0 = 2 * subListSize;
        register int numElements_val1 = seLen - firstListOffset;
        register bool numElements_test = (numElements_val0 < numElements_val1);
        numElements = __TERNARY_ASSIGN(numElements_test, numElements_val0, numElements_val1);
      }

      // Setup the pointers for the source and destination arrays
      register SortEntry* dstptr = dstArray + firstListOffset;    // destination array pointer
      register SortEntry* list0ptr = srcArray + firstListOffset;  // source list 0 pointer
      register SortEntry* list1ptr = list0ptr + subListSize;      // source list 1 pointer
      register SortEntry* list0ptr_end;  // pointer to end of source list0's elements (element after last)
      register SortEntry* list1ptr_end;  // pointer to end of source list1's elements (element after last)
      {
        register bool lenTest = (numElements > subListSize);
        register int list0len_val0 = subListSize;
        register int list1len_val0 = numElements - subListSize;
        register int list0len_val1 = numElements;  // NOTE: list1len_val1 = 0
        register int list0len = __TERNARY_ASSIGN(lenTest, list0len_val0, list0len_val1);
        register int list1len = __TERNARY_ASSIGN(lenTest, list1len_val0, 0);
        // avoid pre-load of sortValue1 from past end of array
        if ( ! lenTest ) list1ptr = list0ptr;
        list0ptr_end = list0ptr + list0len;
        list1ptr_end = list1ptr + list1len;
      }

      // The firstListOffset variable won't be used again until the next
      //   iteration, so go ahead and update it now...
      //   Move forward to the next pair of sub-lists
      firstListOffset += (2 * subListSize);


      // Pre-load values from both source arrays
      register BigReal sortValue0 = list0ptr->sortValue;
      register BigReal sortValue1 = list1ptr->sortValue;
      register int index0 = list0ptr->index;
      register int index1 = list1ptr->index;

      // While both lists have at least one element in them, compare the
      //   heads of each list and place the smaller of the two in the
      //   destination array.
      while (list0ptr < list0ptr_end && list1ptr < list1ptr_end) {

        // Compare the values
        register bool test = (sortValue0 < sortValue1);

        // Place the "winner" in the destination array
        dstptr->sortValue = __TERNARY_ASSIGN(test, sortValue0, sortValue1);
        dstptr->index = __TERNARY_ASSIGN(test, index0, index1);
        dstptr++;

        // Update the pointers
        list0ptr += __TERNARY_ASSIGN(test, 1, 0);
        list1ptr += __TERNARY_ASSIGN(test, 0, 1);

        // Refill the sortValue and index register
        // NOTE: These memory locations are likely to be in cache
        sortValue0 = list0ptr->sortValue;
        sortValue1 = list1ptr->sortValue;
        index0 = list0ptr->index;
        index1 = list1ptr->index;

      } // end while (list0ptr < list0ptr_end && list1ptr < list1ptr_end)

      // NOTE: At this point, at least one of the lists is empty so no
      //   more than one of the loops will be executed.

      // Drain the remaining elements from list0
      while (list0ptr < list0ptr_end) {

        // Place the value into the destination array
        dstptr->sortValue = sortValue0;
        dstptr->index = index0;
        dstptr++;

        // Load the next entry in list0
        list0ptr++;
        sortValue0 = list0ptr->sortValue;
        index0 = list0ptr->index;

      } // end while (list0ptr < list0ptr_end)

      // Drain the remaining elements from list1
      while (list1ptr < list1ptr_end) {

        // Place the value into the destination array
        dstptr->sortValue = sortValue1;
        dstptr->index = index1;
        dstptr++;

        // Load the next entry in list1
        list1ptr++;
        sortValue1 = list1ptr->sortValue;
        index1 = list1ptr->index;

      } // end while (list1ptr < list1ptr_end)

    } // end while (firstListOffset < seLen) {

    // Swap the dstArray and srcArray pointers
    register SortEntry* tmpPtr = dstArray;
    dstArray = srcArray;
    srcArray = tmpPtr;

    // Double the subListSize
    subListSize <<= 1;

  }  // end while (subListSize < seLen)

  // Set the sort values pointers (NOTE: srcArray and dstArray are
  //   swapped at the end of each iteration of the merge sort outer-loop).
  buf = dstArray;
  se = srcArray;

  #undef __TERNARY_ASSIGN
}

sortEntries_selectionSort()

void sortEntries_selectionSort ( SortEntry *const  se, const int  seLen  )

inline

Definition at line 354 of file ComputeNonbondedInl.h.

References __sort_entry::index, and __sort_entry::sortValue.

                                                                             {

  register int i;

  for (i = 0; i < seLen; i++) {

    // Search through the remaining elements, finding the lowest
    //   value, and then swap it with the first remaining element.
    //   Start by assuming the first element is the smallest.
    register int smallestIndex = i;
    register BigReal smallestValue = se[i].sortValue;
    register int j;
    for (j = i + 1; j < seLen; j++) {
      register BigReal currentValue = se[j].sortValue;
      if (currentValue < smallestValue) {
        smallestIndex = j;
        smallestValue = currentValue;
      }
    }

    // Swap the first remaining element with the smallest element
    if (smallestIndex != i) {
      register SortEntry* entryA = se + i;
      register SortEntry* entryB = se + smallestIndex;
      register unsigned int tmpIndex = entryA->index;
      register BigReal tmpSortValue = entryA->sortValue;
      entryA->index = entryB->index;
      entryA->sortValue = entryB->sortValue;
      entryB->index = tmpIndex;
      entryB->sortValue = tmpSortValue;
    }
  }
}