src/gromacs/linearalgebra/gmx_blas/scopy.c

   1 #include "../gmx_blas.h"
   2
   3 void
   4 F77_FUNC(scopy,SCOPY)(int *n__,
   5                       float *dx,
   6                       int *incx__,
   7                       float *dy,
   8                       int *incy__)
   9 {
  10     int i,ix,iy;
  11
  12     int n= *n__;
  13     int incx = *incx__;
  14     int incy = *incy__;
  15
  16     if(incx!=1 || incy!=1)
  17     {
  18         ix = 0;
  19         iy = 0;
  20         if(incx<0)
  21             ix = (1-n)*(incx);
  22         if(incy<0)
  23             iy = (1-n)*(incy);
  24
  25         for(i=0;i<n;i++,ix+=incx,iy+=incy)
  26             dy[iy] = dx[ix];
  27
  28         return;
  29
  30     } else {
  31
  32         /* unroll */
  33
  34         for(i=0;i<(n-8);i+=8) {
  35             dy[i]   = dx[i];
  36             dy[i+1] = dx[i+1];
  37             dy[i+2] = dx[i+2];
  38             dy[i+3] = dx[i+3];
  39             dy[i+4] = dx[i+4];
  40             dy[i+5] = dx[i+5];
  41             dy[i+6] = dx[i+6];
  42             dy[i+7] = dx[i+7];
  43         }
  44         /* continue with current value of i */
  45         for(;i<n;i++)
  46             dy[i] = dx[i];
  47     }
  48 }