/* Copyright (c) 2018 Mozilla
                 2008-2011 Octasic Inc.
                 2012-2017 Jean-Marc Valin */
/*
   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

   - 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.

   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 FOUNDATION 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.
*/

#ifndef VEC_H
#define VEC_H

#include "tansig_table.h"
#include "opus_types.h"
#include <math.h>
#include "arch.h"


#if defined(__AVX__) || defined(__SSE2__)
#include "vec_avx.h"
#elif defined(__ARM_NEON__) || defined(__ARM_NEON)
#include "vec_neon.h"
#else

#define MAX_INPUTS (2048)

#define NO_OPTIMIZATIONS

#ifndef DISABLE_DOT_PROD
#define DOT_PROD
/*#define USE_SU_BIAS*/
#endif

#ifdef DOT_PROD
typedef signed char qweight;
#else
typedef float qweight;
#endif


/* No AVX2/FMA support */
#ifndef LPCNET_TEST
static inline float celt_exp2(float x)
{
   int integer;
   float frac;
   union {
      float f;
      opus_uint32 i;
   } res;
   integer = floor(x);
   if (integer < -50)
      return 0;
   frac = x-integer;
   /* K0 = 1, K1 = log(2), K2 = 3-4*log(2), K3 = 3*log(2) - 2 */
   res.f = 0.99992522f + frac * (0.69583354f
           + frac * (0.22606716f + 0.078024523f*frac));
   res.i = (res.i + (integer<<23)) & 0x7fffffff;
   return res.f;
}
#define celt_exp(x) celt_exp2((x)*1.44269504f)

static inline float tanh_approx(float x)
{
    int i;
    float y, dy;
    float sign=1;
    if (x<0)
    {
       x=-x;
       sign=-1;
    }
    i = (int)floor(.5f+25*x);
    i = IMAX(0, IMIN(200, i));
    x -= .04f*i;
    y = tansig_table[i];
    dy = 1-y*y;
    y = y + x*dy*(1 - y*x);
    return sign*y;
}

static inline float sigmoid_approx(float x)
{
   return .5f + .5f*tanh_approx(.5f*x);
}

static inline void softmax(float *y, const float *x, int N)
{
    int i;
    for (i=0;i<N;i++)
        y[i] = celt_exp(x[i]);
}

static inline void vec_tanh(float *y, const float *x, int N)
{
    int i;
    for (i=0;i<N;i++)
    {
        y[i] = tanh_approx(x[i]);
    }
}

static inline void vec_sigmoid(float *y, const float *x, int N)
{
    int i;
    for (i=0;i<N;i++)
    {
        y[i] = sigmoid_approx(x[i]);
    }
}
#endif
static inline void sgemv_accum16(float *out, const float *weights, int rows, int cols, int col_stride, const float *x)
{
   int i, j;
   for (i=0;i<rows;i+=16)
   {
      for (j=0;j<cols;j++)
      {
         const float * restrict w;
         float * restrict y;
         float xj;
         w = &weights[j*col_stride + i];
         xj = x[j];
         y = &out[i];
         y[0] += w[0]*xj;
         y[1] += w[1]*xj;
         y[2] += w[2]*xj;
         y[3] += w[3]*xj;
         y[4] += w[4]*xj;
         y[5] += w[5]*xj;
         y[6] += w[6]*xj;
         y[7] += w[7]*xj;
         y[8] += w[8]*xj;
         y[9] += w[9]*xj;
         y[10] += w[10]*xj;
         y[11] += w[11]*xj;
         y[12] += w[12]*xj;
         y[13] += w[13]*xj;
         y[14] += w[14]*xj;
         y[15] += w[15]*xj;
      }
   }
}

static inline void sparse_sgemv_accum16(float *out, const float *w, int rows, const int *idx, const float *x)
{
   int i, j;
   for (i=0;i<rows;i+=16)
   {
      int cols;
      cols = *idx++;
      for (j=0;j<cols;j++)
      {
         float * restrict y;
         float xj;
         xj = x[*idx++];
         y = &out[i];
         y[0] += w[0]*xj;
         y[1] += w[1]*xj;
         y[2] += w[2]*xj;
         y[3] += w[3]*xj;
         y[4] += w[4]*xj;
         y[5] += w[5]*xj;
         y[6] += w[6]*xj;
         y[7] += w[7]*xj;
         y[8] += w[8]*xj;
         y[9] += w[9]*xj;
         y[10] += w[10]*xj;
         y[11] += w[11]*xj;
         y[12] += w[12]*xj;
         y[13] += w[13]*xj;
         y[14] += w[14]*xj;
         y[15] += w[15]*xj;
         w += 16;
      }
   }
}

#ifdef DOT_PROD

#define SCALE (128.f*127.f)
#define SCALE_1 (1.f/128.f/127.f)


#ifdef USE_SU_BIAS

static inline void sgemv_accum8x4(float *out, const qweight *w, int rows, int cols, int col_stride, const float *_x)
{
   int i, j;
   unsigned char x[MAX_INPUTS];
   (void)col_stride;
   for (i=0;i<rows;i++) out[i] *= SCALE;
   for (i=0;i<cols;i++) x[i] = 127+(int)floor(.5+127*_x[i]);
   for (i=0;i<rows;i+=8)
   {
      for (j=0;j<cols;j+=4)
      {
         float * restrict y;
         float xj0, xj1, xj2, xj3;
         xj0 = x[j+0];
         xj1 = x[j+1];
         xj2 = x[j+2];
         xj3 = x[j+3];
         y = &out[i];
         y[0] += (w[0]*xj0+w[1]*xj1+w[2]*xj2+w[3]*xj3);
         y[1] += (w[4]*xj0+w[5]*xj1+w[6]*xj2+w[7]*xj3);
         y[2] += (w[8]*xj0+w[9]*xj1+w[10]*xj2+w[11]*xj3);
         y[3] += (w[12]*xj0+w[13]*xj1+w[14]*xj2+w[15]*xj3);
         y[4] += (w[16]*xj0+w[17]*xj1+w[18]*xj2+w[19]*xj3);
         y[5] += (w[20]*xj0+w[21]*xj1+w[22]*xj2+w[23]*xj3);
         y[6] += (w[24]*xj0+w[25]*xj1+w[26]*xj2+w[27]*xj3);
         y[7] += (w[28]*xj0+w[29]*xj1+w[30]*xj2+w[31]*xj3);
         w += 32;
      }
   }
   for (i=0;i<rows;i++) out[i] *= SCALE_1;
}

static inline void sparse_sgemv_accum8x4(float *out, const qweight *w, int rows, int cols, const int *idx, const float *_x)
{
   int i, j;
   unsigned char x[MAX_INPUTS];
   for (i=0;i<rows;i++) out[i] *= SCALE;
   for (i=0;i<cols;i++) x[i] = 127+floor(.5+127*_x[i]);
   for (i=0;i<rows;i+=8)
   {
      int colblocks;
      colblocks = *idx++;
      for (j=0;j<colblocks;j++)
      {
         int pos;
         float * restrict y;
         int xj0, xj1, xj2, xj3;
         pos = (*idx++);
         xj0 = x[pos+0];
         xj1 = x[pos+1];
         xj2 = x[pos+2];
         xj3 = x[pos+3];
         y = &out[i];
         y[0] += (w[0]*xj0+w[1]*xj1+w[2]*xj2+w[3]*xj3);
         y[1] += (w[4]*xj0+w[5]*xj1+w[6]*xj2+w[7]*xj3);
         y[2] += (w[8]*xj0+w[9]*xj1+w[10]*xj2+w[11]*xj3);
         y[3] += (w[12]*xj0+w[13]*xj1+w[14]*xj2+w[15]*xj3);
         y[4] += (w[16]*xj0+w[17]*xj1+w[18]*xj2+w[19]*xj3);
         y[5] += (w[20]*xj0+w[21]*xj1+w[22]*xj2+w[23]*xj3);
         y[6] += (w[24]*xj0+w[25]*xj1+w[26]*xj2+w[27]*xj3);
         y[7] += (w[28]*xj0+w[29]*xj1+w[30]*xj2+w[31]*xj3);
         w += 32;
      }
   }
   for (i=0;i<rows;i++) out[i] *= SCALE_1;
}
#else /*USE_SU_BIAS*/

static inline void sgemv_accum8x4(float *out, const qweight *w, int rows, int cols, int col_stride, const float *_x)
{
   int i, j;
   signed char x[MAX_INPUTS];
   (void)col_stride;
   for (i=0;i<rows;i++) out[i] *= SCALE;
   for (i=0;i<cols;i++) x[i] = (int)floor(.5+127*_x[i]);
   for (i=0;i<rows;i+=8)
   {
      for (j=0;j<cols;j+=4)
      {
         float * restrict y;
         float xj0, xj1, xj2, xj3;
         xj0 = x[j+0];
         xj1 = x[j+1];
         xj2 = x[j+2];
         xj3 = x[j+3];
         y = &out[i];
         y[0] += (w[0]*xj0+w[1]*xj1+w[2]*xj2+w[3]*xj3);
         y[1] += (w[4]*xj0+w[5]*xj1+w[6]*xj2+w[7]*xj3);
         y[2] += (w[8]*xj0+w[9]*xj1+w[10]*xj2+w[11]*xj3);
         y[3] += (w[12]*xj0+w[13]*xj1+w[14]*xj2+w[15]*xj3);
         y[4] += (w[16]*xj0+w[17]*xj1+w[18]*xj2+w[19]*xj3);
         y[5] += (w[20]*xj0+w[21]*xj1+w[22]*xj2+w[23]*xj3);
         y[6] += (w[24]*xj0+w[25]*xj1+w[26]*xj2+w[27]*xj3);
         y[7] += (w[28]*xj0+w[29]*xj1+w[30]*xj2+w[31]*xj3);
         w += 32;
      }
   }
   for (i=0;i<rows;i++) out[i] *= SCALE_1;
}

static inline void sparse_sgemv_accum8x4(float *out, const qweight *w, int rows, int cols, const int *idx, const float *_x)
{
   int i, j;
   signed char x[MAX_INPUTS];
   for (i=0;i<rows;i++) out[i] *= SCALE;
   for (i=0;i<cols;i++) x[i] = floor(.5+127*_x[i]);
   for (i=0;i<rows;i+=8)
   {
      int colblocks;
      colblocks = *idx++;
      for (j=0;j<colblocks;j++)
      {
         int pos;
         float * restrict y;
         int xj0, xj1, xj2, xj3;
         pos = (*idx++);
         xj0 = x[pos+0];
         xj1 = x[pos+1];
         xj2 = x[pos+2];
         xj3 = x[pos+3];
         y = &out[i];
         y[0] += (w[0]*xj0+w[1]*xj1+w[2]*xj2+w[3]*xj3);
         y[1] += (w[4]*xj0+w[5]*xj1+w[6]*xj2+w[7]*xj3);
         y[2] += (w[8]*xj0+w[9]*xj1+w[10]*xj2+w[11]*xj3);
         y[3] += (w[12]*xj0+w[13]*xj1+w[14]*xj2+w[15]*xj3);
         y[4] += (w[16]*xj0+w[17]*xj1+w[18]*xj2+w[19]*xj3);
         y[5] += (w[20]*xj0+w[21]*xj1+w[22]*xj2+w[23]*xj3);
         y[6] += (w[24]*xj0+w[25]*xj1+w[26]*xj2+w[27]*xj3);
         y[7] += (w[28]*xj0+w[29]*xj1+w[30]*xj2+w[31]*xj3);
         w += 32;
      }
   }
   for (i=0;i<rows;i++) out[i] *= SCALE_1;
}
#endif /*USE_SU_BIAS*/

#else /*DOT_PROD*/

#define sgemv_accum8x4 sgemv_accum


static inline void sparse_sgemv_accum8x4(float *out, const qweight *w, int rows, int ignore, const int *idx, const float *x)
{
   int i, j;
   (void)ignore;
   for (i=0;i<rows;i+=8)
   {
      int cols;
      cols = *idx++;
      for (j=0;j<cols;j++)
      {
         int pos;
         float * restrict y;
         float xj0, xj1, xj2, xj3;
         pos = (*idx++);
         xj0 = x[pos+0];
         xj1 = x[pos+1];
         xj2 = x[pos+2];
         xj3 = x[pos+3];
         y = &out[i];
         y[0] += w[0]*xj0;
         y[1] += w[1]*xj0;
         y[2] += w[2]*xj0;
         y[3] += w[3]*xj0;
         y[4] += w[4]*xj0;
         y[5] += w[5]*xj0;
         y[6] += w[6]*xj0;
         y[7] += w[7]*xj0;

         y[0] += w[8]*xj1;
         y[1] += w[9]*xj1;
         y[2] += w[10]*xj1;
         y[3] += w[11]*xj1;
         y[4] += w[12]*xj1;
         y[5] += w[13]*xj1;
         y[6] += w[14]*xj1;
         y[7] += w[15]*xj1;

         y[0] += w[16]*xj2;
         y[1] += w[17]*xj2;
         y[2] += w[18]*xj2;
         y[3] += w[19]*xj2;
         y[4] += w[20]*xj2;
         y[5] += w[21]*xj2;
         y[6] += w[22]*xj2;
         y[7] += w[23]*xj2;

         y[0] += w[24]*xj3;
         y[1] += w[25]*xj3;
         y[2] += w[26]*xj3;
         y[3] += w[27]*xj3;
         y[4] += w[28]*xj3;
         y[5] += w[29]*xj3;
         y[6] += w[30]*xj3;
         y[7] += w[31]*xj3;
         w += 32;
      }
   }
}
#endif /*DOT_PROD*/


#endif /*no optimizations*/
#endif /*VEC_H*/