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/* Copyright (C) 2007 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 2, or (at your option) any later
version.
In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file. (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)
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.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
#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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