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/* Copyright (C) 2007, 2009  Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under

the terms of the GNU General Public License as published by the Free

Software Foundation; either version 3, or (at your option) any later

version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY

WARRANTY; without even the implied warranty of MERCHANTABILITY or

FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

for more details.

Under Section 7 of GPL version 3, you are granted additional

permissions described in the GCC Runtime Library Exception, version

3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and

a copy of the GCC Runtime Library Exception along with this program;

see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

<http://www.gnu.org/licenses/>.  */

#include "bid_internal.h"

/*

 * Takes a BID32 as input and converts it to a BID64 and returns it.

 */

TYPE0_FUNCTION_ARGTYPE1_NORND (UINT64, bid32_to_bid64, UINT32, x)

     UINT64 res;

     UINT32 sign_x;

     int exponent_x;

     UINT32 coefficient_x;

if (!unpack_BID32 (&sign_x, &exponent_x, &coefficient_x, x)) {

    // Inf, NaN, 0

if (((x) & 0x78000000) == 0x78000000) {

  if (((x) & 0x7e000000) == 0x7e000000) {       // sNaN

#ifdef SET_STATUS_FLAGS

    __set_status_flags (pfpsf, INVALID_EXCEPTION);

#endif

  }

  res = (coefficient_x & 0x000fffff);

  res *= 1000000000;

  res |= ((((UINT64) coefficient_x) << 32) & 0xfc00000000000000ull);

  BID_RETURN (res);

}

}

res =

very_fast_get_BID64_small_mantissa (((UINT64) sign_x) << 32,

                                    exponent_x +

                                    DECIMAL_EXPONENT_BIAS -

                                    DECIMAL_EXPONENT_BIAS_32,

                                    (UINT64) coefficient_x);

BID_RETURN (res);

}       // convert_bid32_to_bid64

/*

 * Takes a BID64 as input and converts it to a BID32 and returns it.

 */

#if DECIMAL_CALL_BY_REFERENCE

void

bid64_to_bid32 (UINT32 * pres,

                UINT64 *

                px _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM

                _EXC_INFO_PARAM) {

  UINT64 x;

#else

UINT32

bid64_to_bid32 (UINT64 x _RND_MODE_PARAM _EXC_FLAGS_PARAM

                _EXC_MASKS_PARAM _EXC_INFO_PARAM) {

#endif

  UINT128 Q;

  UINT64 sign_x, coefficient_x, remainder_h, carry, Stemp;

  UINT32 res;

  int_float tempx;

  int exponent_x, bin_expon_cx, extra_digits, rmode = 0, amount;

  unsigned status = 0;

#if DECIMAL_CALL_BY_REFERENCE

#if !DECIMAL_GLOBAL_ROUNDING

  _IDEC_round rnd_mode = *prnd_mode;

#endif

  x = *px;

#endif

  // unpack arguments, check for NaN or Infinity, 0

  if (!unpack_BID64 (&sign_x, &exponent_x, &coefficient_x, x)) {

    if (((x) & 0x7800000000000000ull) == 0x7800000000000000ull) {

      res = (coefficient_x & 0x0003ffffffffffffull);

      res /= 1000000000ull;

      res |= ((coefficient_x >> 32) & 0xfc000000);

#ifdef SET_STATUS_FLAGS

      if ((x & SNAN_MASK64) == SNAN_MASK64)     // sNaN

        __set_status_flags (pfpsf, INVALID_EXCEPTION);

#endif

      BID_RETURN (res);

    }

    exponent_x =

      exponent_x - DECIMAL_EXPONENT_BIAS + DECIMAL_EXPONENT_BIAS_32;

    if (exponent_x < 0)

      exponent_x = 0;

    if (exponent_x > DECIMAL_MAX_EXPON_32)

      exponent_x = DECIMAL_MAX_EXPON_32;

    res = (sign_x >> 32) | (exponent_x << 23);

    BID_RETURN (res);

  }

  exponent_x =

    exponent_x - DECIMAL_EXPONENT_BIAS + DECIMAL_EXPONENT_BIAS_32;

  // check number of digits

  if (coefficient_x >= 10000000) {

    tempx.d = (float) coefficient_x;

    bin_expon_cx = ((tempx.i >> 23) & 0xff) - 0x7f;

    extra_digits = estimate_decimal_digits[bin_expon_cx] - 7;

    // add test for range

    if (coefficient_x >= power10_index_binexp[bin_expon_cx])

      extra_digits++;

#ifndef IEEE_ROUND_NEAREST_TIES_AWAY

#ifndef IEEE_ROUND_NEAREST

    rmode = rnd_mode;

    if (sign_x && (unsigned) (rmode - 1) < 2)

      rmode = 3 - rmode;

#else

    rmode = 0;

#endif

#else

    rmode = 0;

#endif

    exponent_x += extra_digits;

    if ((exponent_x < 0) && (exponent_x + MAX_FORMAT_DIGITS_32 >= 0)) {

      status = UNDERFLOW_EXCEPTION;

      if (exponent_x == -1)

        if (coefficient_x + round_const_table[rmode][extra_digits] >=

            power10_table_128[extra_digits + 7].w[0])

          status = 0;

      extra_digits -= exponent_x;

      exponent_x = 0;

    }

    coefficient_x += round_const_table[rmode][extra_digits];

    __mul_64x64_to_128 (Q, coefficient_x,

                        reciprocals10_64[extra_digits]);

    // now get P/10^extra_digits: shift Q_high right by M[extra_digits]-128

    amount = short_recip_scale[extra_digits];

    coefficient_x = Q.w[1] >> amount;

#ifndef IEEE_ROUND_NEAREST_TIES_AWAY

#ifndef IEEE_ROUND_NEAREST

    if (rmode == 0)      //ROUNDING_TO_NEAREST

#endif

      if (coefficient_x & 1) {

        // check whether fractional part of initial_P/10^extra_digits 

        // is exactly .5

        // get remainder

        remainder_h = Q.w[1] << (64 - amount);

        if (!remainder_h && (Q.w[0] < reciprocals10_64[extra_digits]))

          coefficient_x--;

      }

#endif

#ifdef SET_STATUS_FLAGS

    {

      status |= INEXACT_EXCEPTION;

      // get remainder

      remainder_h = Q.w[1] << (64 - amount);

      switch (rmode) {

      case ROUNDING_TO_NEAREST:

      case ROUNDING_TIES_AWAY:

        // test whether fractional part is 0

        if (remainder_h == 0x8000000000000000ull

            && (Q.w[0] < reciprocals10_64[extra_digits]))

          status = EXACT_STATUS;

        break;

      case ROUNDING_DOWN:

      case ROUNDING_TO_ZERO:

        if (!remainder_h && (Q.w[0] < reciprocals10_64[extra_digits]))

          status = EXACT_STATUS;

        break;

      default:

        // round up

        __add_carry_out (Stemp, carry, Q.w[0],

                         reciprocals10_64[extra_digits]);

        if ((remainder_h >> (64 - amount)) + carry >=

            (((UINT64) 1) << amount))

          status = EXACT_STATUS;

      }

      if (status != EXACT_STATUS)

        __set_status_flags (pfpsf, status);

    }

#endif

  }

  res =

    get_BID32 ((UINT32) (sign_x >> 32),

               exponent_x, coefficient_x, rnd_mode, pfpsf);

  BID_RETURN (res);

}