Eyck Jentzsch
dcaf5467e8
(http://www.jhauser.us/arithmetic/SoftFloat.html) with RISCV specialization and cmake build
159 lines
6.0 KiB
C
159 lines
6.0 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 <stdbool.h>
|
|
#include <stdint.h>
|
|
#include "platform.h"
|
|
#include "internals.h"
|
|
#include "specialize.h"
|
|
#include "softfloat.h"
|
|
|
|
#ifdef SOFTFLOAT_FAST_INT64
|
|
|
|
void
|
|
f128M_mul( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr )
|
|
{
|
|
|
|
*zPtr = f128_mul( *aPtr, *bPtr );
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
void
|
|
f128M_mul( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr )
|
|
{
|
|
const uint32_t *aWPtr, *bWPtr;
|
|
uint32_t *zWPtr;
|
|
uint32_t uiA96;
|
|
int32_t expA;
|
|
uint32_t uiB96;
|
|
int32_t expB;
|
|
bool signZ;
|
|
const uint32_t *ptr;
|
|
uint32_t uiZ96, sigA[4];
|
|
uint_fast8_t shiftDist;
|
|
uint32_t sigB[4];
|
|
int32_t expZ;
|
|
uint32_t sigProd[8], *extSigZPtr;
|
|
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
aWPtr = (const uint32_t *) aPtr;
|
|
bWPtr = (const uint32_t *) bPtr;
|
|
zWPtr = (uint32_t *) zPtr;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
uiA96 = aWPtr[indexWordHi( 4 )];
|
|
expA = expF128UI96( uiA96 );
|
|
uiB96 = bWPtr[indexWordHi( 4 )];
|
|
expB = expF128UI96( uiB96 );
|
|
signZ = signF128UI96( uiA96 ) ^ signF128UI96( uiB96 );
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) {
|
|
if ( softfloat_tryPropagateNaNF128M( aWPtr, bWPtr, zWPtr ) ) return;
|
|
ptr = aWPtr;
|
|
if ( ! expA ) goto possiblyInvalid;
|
|
if ( ! expB ) {
|
|
ptr = bWPtr;
|
|
possiblyInvalid:
|
|
if (
|
|
! fracF128UI96( ptr[indexWordHi( 4 )] )
|
|
&& ! (ptr[indexWord( 4, 2 )] | ptr[indexWord( 4, 1 )]
|
|
| ptr[indexWord( 4, 0 )])
|
|
) {
|
|
softfloat_invalidF128M( zWPtr );
|
|
return;
|
|
}
|
|
}
|
|
uiZ96 = packToF128UI96( signZ, 0x7FFF, 0 );
|
|
goto uiZ96;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
if ( expA ) {
|
|
sigA[indexWordHi( 4 )] = fracF128UI96( uiA96 ) | 0x00010000;
|
|
sigA[indexWord( 4, 2 )] = aWPtr[indexWord( 4, 2 )];
|
|
sigA[indexWord( 4, 1 )] = aWPtr[indexWord( 4, 1 )];
|
|
sigA[indexWord( 4, 0 )] = aWPtr[indexWord( 4, 0 )];
|
|
} else {
|
|
expA = softfloat_shiftNormSigF128M( aWPtr, 0, sigA );
|
|
if ( expA == -128 ) goto zero;
|
|
}
|
|
if ( expB ) {
|
|
sigB[indexWordHi( 4 )] = fracF128UI96( uiB96 ) | 0x00010000;
|
|
sigB[indexWord( 4, 2 )] = bWPtr[indexWord( 4, 2 )];
|
|
sigB[indexWord( 4, 1 )] = bWPtr[indexWord( 4, 1 )];
|
|
sigB[indexWord( 4, 0 )] = bWPtr[indexWord( 4, 0 )];
|
|
} else {
|
|
expB = softfloat_shiftNormSigF128M( bWPtr, 0, sigB );
|
|
if ( expB == -128 ) goto zero;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
expZ = expA + expB - 0x4000;
|
|
softfloat_mul128MTo256M( sigA, sigB, sigProd );
|
|
if (
|
|
sigProd[indexWord( 8, 2 )]
|
|
|| (sigProd[indexWord( 8, 1 )] | sigProd[indexWord( 8, 0 )])
|
|
) {
|
|
sigProd[indexWord( 8, 3 )] |= 1;
|
|
}
|
|
extSigZPtr = &sigProd[indexMultiwordHi( 8, 5 )];
|
|
shiftDist = 16;
|
|
if ( extSigZPtr[indexWordHi( 5 )] & 2 ) {
|
|
++expZ;
|
|
shiftDist = 15;
|
|
}
|
|
softfloat_shortShiftLeft160M( extSigZPtr, shiftDist, extSigZPtr );
|
|
softfloat_roundPackMToF128M( signZ, expZ, extSigZPtr, zWPtr );
|
|
return;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
zero:
|
|
uiZ96 = packToF128UI96( signZ, 0, 0 );
|
|
uiZ96:
|
|
zWPtr[indexWordHi( 4 )] = uiZ96;
|
|
zWPtr[indexWord( 4, 2 )] = 0;
|
|
zWPtr[indexWord( 4, 1 )] = 0;
|
|
zWPtr[indexWord( 4, 0 )] = 0;
|
|
|
|
}
|
|
|
|
#endif
|
|
|