91 lines
3.8 KiB
C++
91 lines
3.8 KiB
C++
/*============================================================================
|
|
|
|
This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
|
|
Package, Release 3e, 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 <stdint.h>
|
|
#include "internals.h"
|
|
#include "specialize.h"
|
|
#include "softfloat.h"
|
|
|
|
int64_t extF80_to_i64_r_minMag(extFloat80_t a, bool exact, struct softfloat_status_t *status)
|
|
{
|
|
uint16_t uiA64;
|
|
int32_t exp;
|
|
uint64_t sig;
|
|
int32_t shiftDist;
|
|
bool sign;
|
|
int64_t absZ;
|
|
|
|
// handle unsupported extended double-precision floating encodings
|
|
if (extF80_isUnsupported(a)) {
|
|
softfloat_raiseFlags(status, softfloat_flag_invalid);
|
|
return i64_fromNaN;
|
|
}
|
|
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
uiA64 = a.signExp;
|
|
exp = expExtF80UI64(uiA64);
|
|
sig = a.signif;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
shiftDist = 0x403E - exp;
|
|
if (64 <= shiftDist) {
|
|
if (exact && (exp | sig)) {
|
|
softfloat_raiseFlags(status, softfloat_flag_inexact);
|
|
}
|
|
return 0;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
sign = signExtF80UI64(uiA64);
|
|
if (shiftDist <= 0) {
|
|
if ((uiA64 == packToExtF80UI64(1, 0x403E)) && (sig == UINT64_C(0x8000000000000000))) {
|
|
return -INT64_C(0x7FFFFFFFFFFFFFFF) - 1;
|
|
}
|
|
softfloat_raiseFlags(status, softfloat_flag_invalid);
|
|
return
|
|
(exp == 0x7FFF) && (sig & UINT64_C(0x7FFFFFFFFFFFFFFF))
|
|
? i64_fromNaN
|
|
: sign ? i64_fromNegOverflow : i64_fromPosOverflow;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
absZ = sig>>shiftDist;
|
|
if (exact && (uint64_t) (sig<<(-shiftDist & 63))) {
|
|
softfloat_raiseFlags(status, softfloat_flag_inexact);
|
|
}
|
|
return sign ? -absZ : absZ;
|
|
}
|