/******************************************************************************

 *                                                                            *

 * Copyright (C) 2018 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at:

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 *

 *****************************************************************************

 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore

*/

#include "ixheaacd_sbr_common.h"

#include "ixheaac_type_def.h"

#include "ixheaac_constants.h"

#include "ixheaac_basic_ops32.h"

#include "ixheaac_basic_ops16.h"

#include "ixheaac_basic_ops40.h"

#include "ixheaac_basic_op.h"

#include "ixheaac_basic_ops.h"

#include "ixheaacd_intrinsics.h"

#include "ixheaacd_common_rom.h"

#include "ixheaacd_basic_funcs.h"

#define sat16_m(a) ixheaac_sat16(a)

VOID ixheaacd_fix_mant_exp_add(WORD16 op1_mant, WORD16 op1_exp, WORD16 op2_mant,

                               WORD16 op2_exp, WORD16 *ptr_result_mant,

                               WORD16 *ptr_result_exp) {

  WORD32 new_mant;

  WORD32 new_exp;

  new_exp = op1_exp - op2_exp;

  if (new_exp < 0) {

    if (new_exp < -31) {

      new_exp = -31;

    }

    op1_mant = op1_mant >> (-new_exp);

    new_exp = op2_exp;

  } else {

    if (new_exp > 31) {

      new_exp = 31;

    }

    op2_mant = op2_mant >> new_exp;

    new_exp = op1_exp;

  }

  new_mant = op1_mant + op2_mant;

  if (ixheaac_abs32(new_mant) >= 0x8000) {

    new_mant = new_mant >> 1;

    new_exp++;

  }

  *ptr_result_mant = new_mant;

  *ptr_result_exp = (WORD16)(new_exp);

}

WORD32 ixheaacd_fix_mant_div(WORD16 op1_mant, WORD16 op2_mant,

                             WORD16 *ptr_result_mant,

                             ixheaacd_misc_tables *pstr_common_tables)

{

  WORD32 pre_shift_val, post_shift_val;

  WORD32 index;

  WORD16 one_by_op2_mant;

  pre_shift_val = ixheaac_norm32(op2_mant) - 16;

  index = (op2_mant << pre_shift_val) >> (SHORT_BITS - 3 - 8);

  index &= (1 << (8 + 1)) - 1;

  if (index == 0) {

    post_shift_val = ixheaac_norm32(op1_mant) - 16;

    *ptr_result_mant = (op1_mant << post_shift_val);

  } else {

    WORD32 ratio_m;

    index = ((index - 1) >> 1);

    one_by_op2_mant = pstr_common_tables->inv_table[index];

    ratio_m = ixheaac_mult16x16in32(one_by_op2_mant, op1_mant);

    post_shift_val = ixheaac_norm32(ratio_m) - 1;

    *ptr_result_mant = (WORD16)((ratio_m << post_shift_val) >> 15);

  }

  return (pre_shift_val - post_shift_val);

}

VOID ixheaacd_fix_mant_exp_sqrt(WORD16 *ptr_in_out, WORD16 *sqrt_table) {

  WORD32 index;

  WORD32 pre_shift_val;

  WORD32 op_mant = *ptr_in_out;

  WORD32 op_exp = *(ptr_in_out + 1);

  WORD32 result_m;

  WORD32 result_e;

  if (op_mant > 0) {

    pre_shift_val = (ixheaac_norm32((WORD16)op_mant) - 16);

    op_exp = (op_exp - pre_shift_val);

    index = (op_mant << pre_shift_val) >> (SHORT_BITS - 3 - 8);

    index &= (1 << (8 + 1)) - 1;

    result_m = sqrt_table[index >> 1];

    if ((op_exp & 1) != 0) {

      result_m = (result_m * 0x5a82) >> 16;

      op_exp += 3;

    }

    result_e = (op_exp >> 1);

  } else {

    result_m = 0;

    result_e = -SHORT_BITS;

  }

  *ptr_in_out++ = (WORD16)result_m;

  *ptr_in_out = (WORD16)result_e;

}

WORD32 ixheaacd_fix_div_dec(WORD32 op1, WORD32 op2) {

  WORD32 quotient = 0;

  UWORD32 abs_num, abs_den;

  WORD32 k;

  WORD32 sign;

  abs_num = ixheaac_abs32(op1 >> 1);

  abs_den = ixheaac_abs32(op2 >> 1);

  sign = op1 ^ op2;

  if (abs_num != 0) {

    for (k = 15; k > 0; k--) {

      quotient = (quotient << 1);

      abs_num = (abs_num << 1);

      if (abs_num >= abs_den) {

        abs_num -= abs_den;

        quotient++;

      }

    }

  }

  if (sign < 0) quotient = -(quotient);

  return quotient;

}

#define ONE_IN_Q30 0x40000000

static PLATFORM_INLINE WORD32 ixheaacd_one_by_sqrt_calc(WORD32 op) {

  WORD32 a = ixheaac_add32_sat(0x900ebee0,

                                ixheaac_mult32x16in32_shl_sat(op, 0x39d9));

  WORD32 iy =

      ixheaac_add32_sat(0x573b645a, ixheaac_mult32x16h_in32_shl_sat(op, a));

  iy = ixheaac_shl32_dir_sat_limit(iy, 1);

  a = ixheaac_mult32_shl_sat(op, iy);

  a = ixheaac_sub32_sat(ONE_IN_Q30, ixheaac_shl32_dir_sat_limit(

                                         ixheaac_mult32_shl_sat(a, iy), 1));

  iy = ixheaac_add32_sat(iy, ixheaac_mult32_shl_sat(a, iy));

  a = ixheaac_mult32_shl_sat(op, iy);

  a = ixheaac_sub32_sat(ONE_IN_Q30, ixheaac_shl32_dir_sat_limit(

                                         ixheaac_mult32_shl_sat(a, iy), 1));

  iy = ixheaac_add32_sat(iy, ixheaac_mult32_shl_sat(a, iy));

  a = ixheaac_mult32_shl_sat(op, iy);

  a = ixheaac_sub32_sat(ONE_IN_Q30, ixheaac_shl32_dir_sat_limit(

                                         ixheaac_mult32_shl_sat(a, iy), 1));

  iy = ixheaac_add32_sat(iy, ixheaac_mult32_shl_sat(a, iy));

  return iy;

}

WORD32 ixheaacd_sqrt(WORD32 op) {

  WORD32 result = 0;

  WORD16 shift;

  if (op != 0) {

    shift = (WORD16)(ixheaac_norm32(op) & ~1);

    op = ixheaac_shl32_dir_sat_limit(op, shift);

    shift = ixheaac_shr32_dir_sat_limit(shift, 1);

    op = ixheaac_mult32_shl_sat(ixheaacd_one_by_sqrt_calc(op), op);

    result = ixheaac_shr32_dir_sat_limit(op, ixheaac_sat16(shift - 1));

  }

  return result;

}