mirror of
https://github.com/ilyakooo0/urbit.git
synced 2024-12-25 07:52:59 +03:00
77 lines
3.0 KiB
C
77 lines
3.0 KiB
C
|
|
||
|
|
/*============================================================================
|
||
|
|
|
||
|
|
This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
|
||
|
|
Package, Release 3, by John R. Hauser.
|
||
|
|
|
||
|
|
Copyright 2011, 2012, 2013, 2014, 2015 The Regents of the University of
|
||
|
|
California (Regents). All Rights Reserved. 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 two paragraphs of disclaimer.
|
||
|
|
Redistributions in binary form must reproduce the above copyright notice,
|
||
|
|
this list of conditions, and the following two paragraphs of disclaimer in the
|
||
|
|
documentation and/or other materials provided with the distribution. Neither
|
||
|
|
the name of the Regents nor the names of its contributors may be used to
|
||
|
|
endorse or promote products derived from this software without specific prior
|
||
|
|
written permission.
|
||
|
|
|
||
|
|
IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
|
||
|
|
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
|
||
|
|
OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
|
||
|
|
BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
|
||
|
|
REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED
|
||
|
|
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
||
|
|
PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
|
||
|
|
HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
|
||
|
|
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
|
||
|
|
|
||
|
|
=============================================================================*/
|
||
|
|
|
||
|
|
#include <stdbool.h>
|
||
|
|
#include <stdint.h>
|
||
|
|
#include "platform.h"
|
||
|
|
#include "internals.h"
|
||
|
|
#include "softfloat.h"
|
||
|
|
|
||
|
|
int_fast32_t
|
||
|
|
softfloat_roundPackToI32(
|
||
|
|
bool sign, uint_fast64_t sig, uint_fast8_t roundingMode, bool exact )
|
||
|
|
{
|
||
|
|
bool roundNearEven;
|
||
|
|
uint_fast8_t roundIncrement, roundBits;
|
||
|
|
uint_fast32_t sig32;
|
||
|
|
union { uint32_t ui; int32_t i; } uZ;
|
||
|
|
int_fast32_t z;
|
||
|
|
|
||
|
|
roundNearEven = (roundingMode == softfloat_round_near_even);
|
||
|
|
roundIncrement = 0x40;
|
||
|
|
if ( ! roundNearEven && (roundingMode != softfloat_round_near_maxMag) ) {
|
||
|
|
roundIncrement =
|
||
|
|
(roundingMode
|
||
|
|
== (sign ? softfloat_round_min : softfloat_round_max))
|
||
|
|
? 0x7F
|
||
|
|
: 0;
|
||
|
|
}
|
||
|
|
roundBits = sig & 0x7F;
|
||
|
|
sig += roundIncrement;
|
||
|
|
if ( sig & UINT64_C( 0xFFFFFF8000000000 ) ) goto invalid;
|
||
|
|
sig32 = sig>>7;
|
||
|
|
sig32 &= ~(uint_fast32_t) (! (roundBits ^ 0x40) & roundNearEven);
|
||
|
|
uZ.ui = sign ? -sig32 : sig32;
|
||
|
|
z = uZ.i;
|
||
|
|
if ( z && ((z < 0) ^ sign) ) goto invalid;
|
||
|
|
if ( exact && roundBits ) {
|
||
|
|
softfloat_exceptionFlags |= softfloat_flag_inexact;
|
||
|
|
}
|
||
|
|
return z;
|
||
|
|
invalid:
|
||
|
|
softfloat_raiseFlags( softfloat_flag_invalid );
|
||
|
|
return sign ? -0x7FFFFFFF - 1 : 0x7FFFFFFF;
|
||
|
|
|
||
|
|
}
|
||
|
|
|