OpenBLAS/kernel/x86_64/cgemv_n.c

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#include <stdlib.h>
#include <stdio.h>
#include "common.h"

#if defined(HASWELL)
#include "cgemv_n_microk_haswell-2.c"
#endif


#define NBMAX 2048

#ifndef HAVE_KERNEL_16x4

static void cgemv_kernel_16x4(BLASLONG n, FLOAT **ap, FLOAT *x, FLOAT *y)
{
	BLASLONG i;
	FLOAT *a0,*a1,*a2,*a3;
	a0 = ap[0];
	a1 = ap[1];
	a2 = ap[2];
	a3 = ap[3];

	for ( i=0; i< 2*n; i+=2 )
	{
#if ( !defined(CONJ) && !defined(XCONJ) ) || ( defined(CONJ) && defined(XCONJ) )
		y[i]   += a0[i]*x[0] - a0[i+1] * x[1];
		y[i+1] += a0[i]*x[1] + a0[i+1] * x[0];
		y[i]   += a1[i]*x[2] - a1[i+1] * x[3];
		y[i+1] += a1[i]*x[3] + a1[i+1] * x[2];
		y[i]   += a2[i]*x[4] - a2[i+1] * x[5];
		y[i+1] += a2[i]*x[5] + a2[i+1] * x[4];
		y[i]   += a3[i]*x[6] - a3[i+1] * x[7];
		y[i+1] += a3[i]*x[7] + a3[i+1] * x[6];
#else 
		y[i]   += a0[i]*x[0] + a0[i+1] * x[1];
		y[i+1] += a0[i]*x[1] - a0[i+1] * x[0];
		y[i]   += a1[i]*x[2] + a1[i+1] * x[3];
		y[i+1] += a1[i]*x[3] - a1[i+1] * x[2];
		y[i]   += a2[i]*x[4] + a2[i+1] * x[5];
		y[i+1] += a2[i]*x[5] - a2[i+1] * x[4];
		y[i]   += a3[i]*x[6] + a3[i+1] * x[7];
		y[i+1] += a3[i]*x[7] - a3[i+1] * x[6];
#endif
	}
}
	
#endif

static void cgemv_kernel_16x1(BLASLONG n, FLOAT *ap, FLOAT *x, FLOAT *y)
{
	BLASLONG i;
	FLOAT *a0;
	a0 = ap;

	for ( i=0; i< 2*n; i+=2 )
	{
#if ( !defined(CONJ) && !defined(XCONJ) ) || ( defined(CONJ) && defined(XCONJ) )
		y[i]   += a0[i]*x[0] - a0[i+1] * x[1];
		y[i+1] += a0[i]*x[1] + a0[i+1] * x[0];
#else 
		y[i]   += a0[i]*x[0] + a0[i+1] * x[1];
		y[i+1] += a0[i]*x[1] - a0[i+1] * x[0];
#endif

	}
}
	

static void zero_y(BLASLONG n, FLOAT *dest)
{
	BLASLONG i;
	for ( i=0; i<2*n; i++ )
	{
		*dest = 0.0;
		dest++;
	}
}



static void add_y(BLASLONG n, FLOAT *src, FLOAT *dest, BLASLONG inc_dest,FLOAT alpha_r, FLOAT alpha_i)
{
	BLASLONG i;
	FLOAT temp_r;
	FLOAT temp_i;
	for ( i=0; i<n; i++ )
	{
#if !defined(XCONJ) 
		temp_r = alpha_r * src[0] - alpha_i * src[1];
		temp_i = alpha_r * src[1] + alpha_i * src[0];
#else
		temp_r =  alpha_r * src[0] + alpha_i * src[1];
		temp_i = -alpha_r * src[1] + alpha_i * src[0];
#endif

		*dest += temp_r;
		*(dest+1) += temp_i;

		src+=2;
		dest += inc_dest;
	}
}

int CNAME(BLASLONG m, BLASLONG n, BLASLONG dummy1, FLOAT alpha_r,FLOAT alpha_i, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *buffer)
{
	BLASLONG i;
	BLASLONG j;
	FLOAT *a_ptr;
	FLOAT *x_ptr;
	FLOAT *y_ptr;
	FLOAT *ap[4];
	BLASLONG n1;
	BLASLONG m1;
	BLASLONG m2;
	BLASLONG n2;
	FLOAT xbuffer[8],*ybuffer;


#if 0
printf("%s %d %d %.16f %.16f %d %d %d\n","zgemv_n",m,n,alpha_r,alpha_i,lda,inc_x,inc_y);
#endif

	if ( m < 1 ) return(0);
	if ( n < 1 ) return(0);

	ybuffer = buffer;
	
	inc_x *= 2;
	inc_y *= 2;
	lda   *= 2;

	n1 = n / 4 ;
	n2 = n % 4 ;
	
	m1 = m - ( m % 16 );
	m2 = (m % NBMAX) - (m % 16) ;
	
	y_ptr = y;

	BLASLONG NB = NBMAX;

	while ( NB == NBMAX )
	{
		
		m1 -= NB;
		if ( m1 < 0)
		{
			if ( m2 == 0 ) break;	
			NB = m2;
		}
		
		a_ptr = a;
		x_ptr = x;
		zero_y(NB,ybuffer);
		for( i = 0; i < n1 ; i++)
		{

			xbuffer[0] = x_ptr[0];
			xbuffer[1] = x_ptr[1];
			x_ptr += inc_x;	
			xbuffer[2] = x_ptr[0];
			xbuffer[3] = x_ptr[1];
			x_ptr += inc_x;	
			xbuffer[4] = x_ptr[0];
			xbuffer[5] = x_ptr[1];
			x_ptr += inc_x;	
			xbuffer[6] = x_ptr[0];
			xbuffer[7] = x_ptr[1];
			x_ptr += inc_x;	

			ap[0] = a_ptr;
			ap[1] = a_ptr + lda;
			ap[2] = ap[1] + lda;
			ap[3] = ap[2] + lda;
			cgemv_kernel_16x4(NB,ap,xbuffer,ybuffer);
			a_ptr += 4 * lda;
		}

		for( i = 0; i < n2 ; i++)
		{
			xbuffer[0] = x_ptr[0];
			xbuffer[1] = x_ptr[1];
			x_ptr += inc_x;	
			cgemv_kernel_16x1(NB,a_ptr,xbuffer,ybuffer);
			a_ptr += 1 * lda;

		}
		add_y(NB,ybuffer,y_ptr,inc_y,alpha_r,alpha_i);
		a     += 2 * NB;
		y_ptr += NB * inc_y;
	}

	j=0;
	while ( j < (m % 16))
	{
		a_ptr = a;
		x_ptr = x;
		FLOAT temp_r = 0.0;
		FLOAT temp_i = 0.0;
		for( i = 0; i < n; i++ )
		{
#if ( !defined(CONJ) && !defined(XCONJ) ) || ( defined(CONJ) && defined(XCONJ) )
			temp_r += a_ptr[0] * x_ptr[0] - a_ptr[1] * x_ptr[1];
			temp_i += a_ptr[0] * x_ptr[1] + a_ptr[1] * x_ptr[0];
#else
			temp_r += a_ptr[0] * x_ptr[0] + a_ptr[1] * x_ptr[1];
			temp_i += a_ptr[0] * x_ptr[1] - a_ptr[1] * x_ptr[0];
#endif

			a_ptr += lda;
			x_ptr += inc_x;
		}

#if !defined(XCONJ) 
		y_ptr[0] += alpha_r * temp_r - alpha_i * temp_i;
		y_ptr[1] += alpha_r * temp_i + alpha_i * temp_r;
#else
		y_ptr[0] += alpha_r * temp_r + alpha_i * temp_i;
		y_ptr[1] -= alpha_r * temp_i - alpha_i * temp_r;
#endif
		y_ptr += inc_y;
		a+=2;
		j++;
	}
	return(0);
}