ICODE-ADC/lammps
4
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

restore old qsort() based code and add preprocessor directives to switch

Browse Source 
-DLMP_USE_LIBC_QSORT will use qsort() from libc to sort (requires static/global variables).
-DLMP_USE_MERGE_SORT will use a plain merge sort. slightly slower for expensive comparisons.
-DLMP_USE_HYBRID_SORT will use hybrid merge sort. faster than merge sort (no static/global variables)
This commit is contained in:
Axel Kohlmeyer
2017-06-16 18:17:48 -04:00
parent 2a6f026853
commit c1b0b1b3f9
5 changed files with 162 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

85
src/dump.cpp
View File

@ -30,7 +30,12 @@
using namespace LAMMPS_NS;
#if defined(LMP_USE_LIBC_QSORT)
// allocate space for static class variable
Dump *Dump::dumpptr;
#else
#include "mergesort.h"
#endif
#define BIG 1.0e20
#define EPSILON 1.0e-6
@ -687,12 +692,22 @@ void Dump::sort()
index[idsort[i]-idlo] = i;
}
#if defined(LMP_USE_LIBC_QSORT)
if (!reorderflag) {
dumpptr = this;
for (i = 0; i < nme; i++) index[i] = i;
if (sortcol == 0) qsort(index,nme,sizeof(int),idcompare);
else if (sortorder == ASCEND) qsort(index,nme,sizeof(int),bufcompare);
else qsort(index,nme,sizeof(int),bufcompare_reverse);
}
#else
if (!reorderflag) {
for (i = 0; i < nme; i++) index[i] = i;
if (sortcol==0) merge_sort(index,nme,(void *)this,idcompare);
else if (sortorder==ASCEND) merge_sort(index,nme,(void *)this,bufcompare);
if (sortcol == 0) merge_sort(index,nme,(void *)this,idcompare);
else if (sortorder == ASCEND) merge_sort(index,nme,(void *)this,bufcompare);
else merge_sort(index,nme,(void *)this,bufcompare_reverse);
}
#endif
// reset buf size and maxbuf to largest of any post-sort nme values
// this insures proc 0 can receive everyone's info
@ -713,6 +728,69 @@ void Dump::sort()
memcpy(&buf[i*size_one],&bufsort[index[i]*size_one],nbytes);
}
#if defined(LMP_USE_LIBC_QSORT)
/* ----------------------------------------------------------------------
compare two atom IDs
called via qsort() in sort() method
is a static method so access data via dumpptr
------------------------------------------------------------------------- */
int Dump::idcompare(const void *pi, const void *pj)
{
tagint *idsort = dumpptr->idsort;
int i = *((int *) pi);
int j = *((int *) pj);
if (idsort[i] < idsort[j]) return -1;
if (idsort[i] > idsort[j]) return 1;
return 0;
}
/* ----------------------------------------------------------------------
compare two buffer values with size_one stride
called via qsort() in sort() method
is a static method so access data via dumpptr
sort in ASCENDing order
------------------------------------------------------------------------- */
int Dump::bufcompare(const void *pi, const void *pj)
{
double *bufsort = dumpptr->bufsort;
int size_one = dumpptr->size_one;
int sortcolm1 = dumpptr->sortcolm1;
int i = *((int *) pi)*size_one + sortcolm1;
int j = *((int *) pj)*size_one + sortcolm1;
if (bufsort[i] < bufsort[j]) return -1;
if (bufsort[i] > bufsort[j]) return 1;
return 0;
}
/* ----------------------------------------------------------------------
compare two buffer values with size_one stride
called via qsort() in sort() method
is a static method so access data via dumpptr
sort in DESCENDing order
------------------------------------------------------------------------- */
int Dump::bufcompare_reverse(const void *pi, const void *pj)
{
double *bufsort = dumpptr->bufsort;
int size_one = dumpptr->size_one;
int sortcolm1 = dumpptr->sortcolm1;
int i = *((int *) pi)*size_one + sortcolm1;
int j = *((int *) pj)*size_one + sortcolm1;
if (bufsort[i] > bufsort[j]) return -1;
if (bufsort[i] < bufsort[j]) return 1;
return 0;
}
#else
/* ----------------------------------------------------------------------
compare two atom IDs
called via merge_sort() in sort() method
@ -745,6 +823,7 @@ int Dump::bufcompare(const int i, const int j, void *ptr)
else if (bufsort[ii] > bufsort[jj]) return 1;
else return 0;
}
/* ----------------------------------------------------------------------
compare two buffer values with size_one stride
called via merge_sort() in sort() method
@ -766,6 +845,8 @@ int Dump::bufcompare_reverse(const int i, const int j, void *ptr)
else return 0;
}
#endif
/* ----------------------------------------------------------------------
process params common to all dumps here
if unknown param, call modify_param specific to the dump