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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);
}
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