mirror of
https://github.com/urbit/shrub.git
synced 2024-12-23 10:52:12 +03:00
112 lines
4.2 KiB
C
112 lines
4.2 KiB
C
|
|
/*============================================================================
|
|
|
|
This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
|
|
Package, Release 3c, by John R. Hauser.
|
|
|
|
Copyright 2011, 2012, 2013, 2014, 2015, 2016 The Regents of the University of
|
|
California. All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are met:
|
|
|
|
1. Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions, and the following disclaimer.
|
|
|
|
2. Redistributions in binary form must reproduce the above copyright notice,
|
|
this list of conditions, and the following disclaimer in the documentation
|
|
and/or other materials provided with the distribution.
|
|
|
|
3. Neither the name of the University nor the names of its contributors may
|
|
be used to endorse or promote products derived from this software without
|
|
specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
|
|
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
|
|
DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
|
|
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
=============================================================================*/
|
|
|
|
#include <stdbool.h>
|
|
#include <stdint.h>
|
|
#include "platform.h"
|
|
#include "internals.h"
|
|
#include "specialize.h"
|
|
#include "softfloat.h"
|
|
|
|
#ifdef SOFTFLOAT_FAST_INT64
|
|
|
|
uint_fast32_t extF80M_to_ui32_r_minMag( const extFloat80_t *aPtr, bool exact )
|
|
{
|
|
|
|
return extF80_to_ui32_r_minMag( *aPtr, exact );
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
uint_fast32_t extF80M_to_ui32_r_minMag( const extFloat80_t *aPtr, bool exact )
|
|
{
|
|
const struct extFloat80M *aSPtr;
|
|
uint_fast16_t uiA64;
|
|
int32_t exp;
|
|
uint64_t sig;
|
|
int32_t shiftDist;
|
|
bool sign;
|
|
uint64_t shiftedSig;
|
|
uint32_t z;
|
|
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
aSPtr = (const struct extFloat80M *) aPtr;
|
|
uiA64 = aSPtr->signExp;
|
|
exp = expExtF80UI64( uiA64 );
|
|
sig = aSPtr->signif;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
if ( ! sig && (exp != 0x7FFF) ) return 0;
|
|
shiftDist = 0x403E - exp;
|
|
if ( 64 <= shiftDist ) {
|
|
if ( exact ) softfloat_exceptionFlags |= softfloat_flag_inexact;
|
|
return 0;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
sign = signExtF80UI64( uiA64 );
|
|
if ( shiftDist < 0 ) {
|
|
if ( sign || sig>>32 || (shiftDist <= -31) ) goto invalid;
|
|
shiftedSig = (uint64_t) (uint32_t) sig<<-shiftDist;
|
|
if ( shiftedSig>>32 ) goto invalid;
|
|
z = shiftedSig;
|
|
} else {
|
|
shiftedSig = sig;
|
|
if ( shiftDist ) shiftedSig >>= shiftDist;
|
|
if ( shiftedSig>>32 ) goto invalid;
|
|
z = shiftedSig;
|
|
if ( sign && z ) goto invalid;
|
|
if ( exact && shiftDist && ((uint64_t) z<<shiftDist != sig) ) {
|
|
softfloat_exceptionFlags |= softfloat_flag_inexact;
|
|
}
|
|
}
|
|
return z;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
invalid:
|
|
softfloat_raiseFlags( softfloat_flag_invalid );
|
|
return
|
|
(exp == 0x7FFF) && (sig & UINT64_C( 0x7FFFFFFFFFFFFFFF ))
|
|
? ui32_fromNaN
|
|
: sign ? ui32_fromNegOverflow : ui32_fromPosOverflow;
|
|
|
|
}
|
|
|
|
#endif
|
|
|