MATHLIB_sin.cpp

Go to the documentation of this file.

/******************************************************************************
 * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
 *
 * 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.
 *
 *    Neither the name of Texas Instruments Incorporated 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 COPYRIGHT
 * OWNER 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.
 *
 ******************************************************************************/
 
#define ELEMENT_COUNT(x) c7x::element_count_of<x>::value
 
/******************************************************************************/
/*                                                                            */
/* Includes                                                                   */
/*                                                                            */
/******************************************************************************/
 
#include "MATHLIB_types.h"
#include "MATHLIB_utility.h"
#include <cstddef>
 
/******************************************************************************/
/*                                                                            */
/* MATHLIB_sin                                                                 */
/*                                                                            */
/******************************************************************************/
 
// this method performs sine computation of input vector
template <typename T> MATHLIB_STATUS MATHLIB_sin(size_t length, T *pSrc, T *pDst);
 
template <> MATHLIB_STATUS MATHLIB_sin<float>(size_t length, float *pSrc, float *pDst)
{
 
   // variables
   MATHLIB_STATUS status       = MATHLIB_SUCCESS; // return function status
   size_t         numBlocks    = 0;               // compute loop's iteration count
   size_t         remNumBlocks = 0;               // when numBlocks is not a multiple of SIMD width
 
   // derive c7x vector type from template typename
   typedef typename c7x::make_full_vector<float>::type vec;
 
   // Compile-time decision: float_vec => int_vec and double_vec=> long_vec
   typedef
       typename std::conditional<ELEMENT_COUNT(c7x::float_vec) == ELEMENT_COUNT(vec), c7x::int_vec, c7x::long_vec>::type
           vec_type;
 
   __SE_TEMPLATE_v1 se0Params = __gen_SE_TEMPLATE_v1();
   __SA_TEMPLATE_v1 sa0Params = __gen_SA_TEMPLATE_v1();
 
   status = MATHLIB_checkParams(length, pSrc, pDst);
 
   if (status == MATHLIB_SUCCESS) {
 
      MATHLIB_SE0SA01DSequentialInit(&se0Params, &sa0Params, length, pSrc, pDst);
 
      // calculate compute loop's iteration counter
      numBlocks    = length / c7x::element_count_of<vec>::value;
      remNumBlocks = length % c7x::element_count_of<vec>::value;
      if (remNumBlocks) {
         numBlocks++;
      }
 
      // open SE0, SE1, and SA0 for reading and writing operands
      MATHLIB_SE0SA0Open(&se0Params, &sa0Params, pSrc);
 
      /**********************************************************************/
      /* Create and assign values for constants employed on cos computation */
      /**********************************************************************/
 
      vec      InvPI, One, MAX, Zero, s1, s2, s3, s4, C1, C2, X, Y, Z, F, G, R, negativeOne, Sign;
      vec_type N, int_one;
 
      InvPI       = (vec) 0.318309886183791;
      One         = (vec) 1.0;
      MAX         = (vec) 1048576.0;
      Zero        = (vec) 0.0;
      s1          = (vec) -1.666665668e-1;
      s2          = (vec) 8.333025139e-3;
      s3          = (vec) -1.980741872e-4;
      s4          = (vec) 2.601903036e-6;
      C1          = (vec) 3.140625;
      C2          = (vec) 9.67653589793e-4;
      negativeOne = (vec) -1;
 
      int_one = (vec_type) 1;
 
      Sign = One;
 
      // compute loop to perform vector sin
      for (size_t i = 0; i < numBlocks; i++) {
         vec a = c7x::strm_eng<0, vec>::get_adv();
         Y     = a;
 
         //      if (__abs(Y) > (vec)MAX) {
         //       Y = Zero;
         //     }
         __vpred cmp_gt = __cmp_lt_pred((vec) MAX, __abs(Y));
         Y              = __select(cmp_gt, Zero, Y);
 
         // X = Y * (1/PI)
         X = Y * InvPI;
 
         N = __float_to_int(X);
         Z = c7x::convert<vec>(N);
 
         /**********************************************************************/
         /* Sign checking for quadrant 3 or 4                                  */
         /**********************************************************************/
 
         //      if ((N % 2) != 0) {
         //         Sign = -Sign;
         //      }
         vec_type andN     = N & int_one;
         vec convert_andN   = c7x::convert<vec>(andN);
         __vpred  cmp_mod  = __cmp_le_pred(convert_andN, Zero);
         vec      Sign_vec = __select(cmp_mod, Sign, negativeOne);
 
         F = (Y - (Z * C1)) - (Z * C2);
         G = F * F;
 
         R = ((((((s4 * G) + s3) * G) + s2) * G) + s1) * G;
 
         vec     output = ((F + (F * R)) * Sign_vec);
         __vpred tmp    = c7x::strm_agen<0, vec>::get_vpred();
         vec    *VB1    = c7x::strm_agen<0, vec>::get_adv(pDst);
 
         __vstore_pred(tmp, VB1, output);
      }
 
      MATHLIB_SE0SA0Close();
   }
 
   return status;
}
 
template <> MATHLIB_STATUS MATHLIB_sin<double>(size_t length, double *pSrc, double *pDst)
{
 
   // variables
   MATHLIB_STATUS status       = MATHLIB_SUCCESS; // return function status
   size_t         numBlocks    = 0;               // compute loop's iteration count
   size_t         remNumBlocks = 0;               // when numBlocks is not a multiple of SIMD width
 
   // derive c7x vector type from template typename
   typedef typename c7x::make_full_vector<c7x::double_vec>::type vec;
   typedef typename c7x::make_full_vector<c7x::int_vec>::type    vec_type;
 
   __SE_TEMPLATE_v1 se0Params = __gen_SE_TEMPLATE_v1();
   __SA_TEMPLATE_v1 sa0Params = __gen_SA_TEMPLATE_v1();
 
   status = MATHLIB_checkParams(length, pSrc, pDst);
 
   if (status == MATHLIB_SUCCESS) {
 
      MATHLIB_SE0SA01DSequentialInit(&se0Params, &sa0Params, length, pSrc, pDst);
 
      // calculate compute loop's iteration counter
      numBlocks    = length / c7x::element_count_of<vec>::value;
      remNumBlocks = length % c7x::element_count_of<vec>::value;
      if (remNumBlocks) {
         numBlocks++;
      }
 
      // open SE0 and SA0 for reading and writing operands
      MATHLIB_SE0SA0Open(&se0Params, &sa0Params, pSrc);
 
      /**********************************************************************/
      /* Create and assign values for constants employed on cos computation */
      /**********************************************************************/
      vec InvPI, C1, C2, r8, r7, r6, r5, r4, r3, r2, r1, MAX, Zero, Sign, negativeOne;
 
      InvPI = (vec) 0.31830988618379067154;
      C1    = (vec) 3.1416015625;
      C2    = (vec) -8.908910206761537356617e-6;
      r8    = (vec) 2.7204790957888846175e-15;
      r7    = (vec) -7.6429178068910467734e-13;
      r6    = (vec) 1.6058936490371589114e-10;
      r5    = (vec) -2.5052106798274584544e-8;
      r4    = (vec) 2.7557319210152756119e-6;
      r3    = (vec) -1.9841269841201840457e-4;
      r2    = (vec) 8.3333333333331650314e-3;
      r1    = (vec) -1.6666666666666665052e-1;
      MAX   = (vec) 1.073741824e+09;
      Zero  = (vec) 0.0;
      Sign  = (vec) 1.0;
 
      negativeOne = (vec) -1.0;
 
      vec_type int_one = (vec_type) 1;
 
      vec      X, Z, F1, F2, G, R;
      vec_type N;
 
      // compute loop to perform vector sin
      for (size_t i = 0; i < numBlocks; i++) {
         vec a = c7x::strm_eng<0, vec>::get_adv();
 
         F1 = a;
 
         __vpred cmp_gt = __cmp_lt_pred((vec) MAX, __abs(F1));
         F1             = __select(cmp_gt, Zero, F1);
 
         X = F1 * InvPI;
         N = __double_to_int(X);
         Z = __low_int_to_double(N);
 
         vec_type andN         = N & int_one;
         vec      convert_andN = __low_int_to_double(andN);
 
         __vpred cmp_mod  = __cmp_le_pred(convert_andN, Zero);
         vec     Sign_vec = __select(cmp_mod, Sign, negativeOne);
 
         F1 = (F1 - (Z * C1)) - (Z * C2);
         F2 = F1 * F1;
         G  = F2 * F2;
 
         R = ((((((G * r8) + r6) * G) + r4) * G) + r2) * G;
         X = ((((((G * r7) + r5) * G) + r3) * G) + r1) * F2;
         R = R + X;
         G = ((F1 + (F1 * R)) * Sign_vec);
 
         __vpred tmp = c7x::strm_agen<0, vec>::get_vpred();
         vec    *VB1 = c7x::strm_agen<0, vec>::get_adv(pDst);
         __vstore_pred(tmp, VB1, G);
      }
 
      MATHLIB_SE0SA0Close();
   }
 
   return status;
}
 
/******************************************************************************/
/*                                                                            */
/* C-interface wrapper functions                                              */
/*                                                                            */
/******************************************************************************/
 
extern "C" {
 
// single-precision wrapper
MATHLIB_STATUS MATHLIB_sin_sp(size_t length, float *pSrc, float *pDst)
{
   MATHLIB_STATUS status = MATHLIB_sin<float>(length, pSrc, pDst);
   return status;
}
 
 
// double-precision wrapper
MATHLIB_STATUS MATHLIB_sin_dp(size_t length, double *pSrc, double *pDst)
{
   MATHLIB_STATUS status = MATHLIB_sin<double>(length, pSrc, pDst);
   return status;
}
 
 
} // extern "C"