atl_zero.c

基于Blas CLapck的.用过的人知道是干啥的

/*
 *             Automatically Tuned Linear Algebra Software v3.8.0
 *                    (C) Copyright 1999 R. Clint Whaley
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions, and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *   3. The name of the ATLAS group or the names of its contributers may
 *      not be used to endorse or promote products derived from this
 *      software without specific written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ATLAS GROUP OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include "atlas_misc.h"

void Mjoin(PATL,zero)(const int N, TYPE *X, const int incX)
/*
 * X <- 0
 */
{
   int i, n;
   if (incX == 1)
   {
      n = N SHIFT;
      i = n >> 5;
      if (i)
      {
         n -= (i << 5);
         do
         {
            *X = X[1] = X[2] = X[3] = X[4] = X[5] = X[6] = X[7] = X[8] = X[9] =
            X[10] = X[11] = X[12] = X[13] = X[14] = X[15] = X[16] = X[17] =
            X[18] = X[19] = X[20] = X[21] = X[22] = X[23] = X[24] = X[25] =
            X[26] = X[27] = X[28] = X[29] = X[30] = X[31] = ATL_rzero;
            X += 32;
         }
         while(--i);
      }
      if (n >> 4) /* >= 16 */
      {
         *X = X[1] = X[2] = X[3] = X[4] = X[5] = X[6] = X[7] = X[8] = X[9] =
         X[10] = X[11] = X[12] = X[13] = X[14] = X[15] = ATL_rzero;
         X += 16;
         n -= 16;
      }
      if (n >> 3) /* >= 8 */
      {
         *X = X[1] = X[2] = X[3] = X[4] = X[5] = X[6] = X[7] = ATL_rzero;
         X += 8;
         n -= 8;
      }
      switch(n)
      {
         case 1:
            *X = ATL_rzero;
            break;
         case 2:
            *X = X[1] = ATL_rzero;
            break;
         case 3:
            *X = X[1] = X[2] = ATL_rzero;
            break;
         case 4:
            *X = X[1] = X[2] = X[3] = ATL_rzero;
            break;
         case 5:
            *X = X[1] = X[2] = X[3] = X[4] = ATL_rzero;
            break;
         case 6:
            *X = X[1] = X[2] = X[3] = X[4] = X[5] = ATL_rzero;
            break;
         case 7:
            *X = X[1] = X[2] = X[3] = X[4] = X[5] = X[6] = ATL_rzero;
            break;
         default:;
      }
   }
   else
   {
      #ifdef TREAL
         for (i=N; i; i--, X += incX) *X = ATL_rzero;
      #else
         for (n=incX<<1, i=N; i; i--, X += n) *X = X[1] = ATL_rzero;
      #endif
   }
}