THUNDERX: Add optimized version of daxpy

This is better for single core but does not change anything for multiple cores

kernel/arm64/KERNEL.THUNDERX

@@ -2,3 +2,5 @@ include $(KERNELDIR)/KERNEL.ARMV8
 
 SDOTKERNEL=dot-thunderx.c
 DDOTKERNEL=ddot-thunderx.c
+DAXPYKERNEL=daxpy-thunderx.c
+

kernel/arm64/daxpy-thunderx.c

@@ -0,0 +1,151 @@
+/***************************************************************************
+Copyright (c) 2014, The OpenBLAS Project
+All rights reserved.
+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. Neither the name of the OpenBLAS project nor the names of
+its contributors may be used to endorse or promote products
+derived from this software without specific prior 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 OPENBLAS PROJECT OR 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 "common.h"
+#include <arm_neon.h>
+
+#define prefetch(a) __asm__("prfm PLDL1STRM, [%0]"::"r"(a):"memory");
+//#define prefetch(a)
+
+static void daxpy_kernel_8(BLASLONG n, FLOAT *x, FLOAT *y, FLOAT *alpha)
+{
+	BLASLONG register i = 0;
+	double a = *alpha;
+
+#if 0
+        prefetch(x + 128/sizeof(*x));
+        prefetch(y + 128/sizeof(*y));
+#endif
+        prefetch(x + 2*128/sizeof(*x));
+        prefetch(y + 2*128/sizeof(*y));
+        prefetch(x + 3*128/sizeof(*x));
+        prefetch(y + 3*128/sizeof(*y));
+        prefetch(x + 4*128/sizeof(*x));
+        prefetch(y + 4*128/sizeof(*y));
+
+	while(i < n)
+        {
+	      double y0, y1, y2, y3;
+	      double y4, y5, y6, y7;
+	      double *xx;
+	      double *yy;
+              y0 = a * x[0] + y[0];
+              y1 = a * x[1] + y[1];
+              y2 = a * x[2] + y[2];
+              y3 = a * x[3] + y[3];
+              y4 = a * x[4] + y[4];
+              y5 = a * x[5] + y[5];
+              y6 = a * x[6] + y[6];
+              y7 = a * x[7] + y[7];
+	      asm("":"+w"(y0),"+w"(y1),"+w"(y2),"+w"(y3),"+w"(y4),"+w"(y5),"+w"(y6),"+w"(y7));
+	      y[0] = y0;
+	      y[1] = y1;
+	      y[2] = y2;
+	      y[3] = y3;
+	      y[4] = y4;
+	      y[5] = y5;
+	      y[6] = y6;
+	      y[7] = y7;
+
+              xx = (x + 4*128/sizeof(*x));
+              yy = (y + 4*128/sizeof(*y));
+	      asm("":"+r"(yy)::"memory");
+	      prefetch(xx);
+	      prefetch(yy);
+
+	      y += 8;
+	      x += 8;
+              i += 8 ;
+	}
+
+}
+
+
+int CNAME(BLASLONG n, BLASLONG dummy0, BLASLONG dummy1, FLOAT da, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *dummy, BLASLONG dummy2)
+{
+	BLASLONG i=0;
+	BLASLONG ix=0,iy=0;
+
+	if ( n <= 0 )  return(0);
+
+	if ( (inc_x == 1) && (inc_y == 1) )
+	{
+
+		BLASLONG n1 = n & -32;
+
+		if ( n1 )
+			daxpy_kernel_8(n1, x, y , &da );
+
+		i = n1;
+		while(i < n)
+		{
+
+			y[i] += da * x[i] ;
+			i++ ;
+
+		}
+		return(0);
+
+
+	}
+
+	BLASLONG n1 = n & -4;
+
+	while(i < n1)
+	{
+
+		FLOAT m1      = da * x[ix] ;
+		FLOAT m2      = da * x[ix+inc_x] ;
+		FLOAT m3      = da * x[ix+2*inc_x] ;
+		FLOAT m4      = da * x[ix+3*inc_x] ;
+
+		y[iy]         += m1 ;
+		y[iy+inc_y]   += m2 ;
+		y[iy+2*inc_y] += m3 ;
+		y[iy+3*inc_y] += m4 ;
+
+		ix  += inc_x*4 ;
+		iy  += inc_y*4 ;
+		i+=4 ;
+
+	}
+
+	while(i < n)
+	{
+
+		y[iy] += da * x[ix] ;
+		ix  += inc_x ;
+		iy  += inc_y ;
+		i++ ;
+
+	}
+	return(0);
+
+}
+
+