forked from Github_Repos/cvw
227 lines
8.3 KiB
C
227 lines
8.3 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"
|
|
|
|
float16_t
|
|
softfloat_mulAddF16(
|
|
uint_fast16_t uiA, uint_fast16_t uiB, uint_fast16_t uiC, uint_fast8_t op )
|
|
{
|
|
bool signA;
|
|
int_fast8_t expA;
|
|
uint_fast16_t sigA;
|
|
bool signB;
|
|
int_fast8_t expB;
|
|
uint_fast16_t sigB;
|
|
bool signC;
|
|
int_fast8_t expC;
|
|
uint_fast16_t sigC;
|
|
bool signProd;
|
|
uint_fast16_t magBits, uiZ;
|
|
struct exp8_sig16 normExpSig;
|
|
int_fast8_t expProd;
|
|
uint_fast32_t sigProd;
|
|
bool signZ;
|
|
int_fast8_t expZ;
|
|
uint_fast16_t sigZ;
|
|
int_fast8_t expDiff;
|
|
uint_fast32_t sig32Z, sig32C;
|
|
int_fast8_t shiftDist;
|
|
union ui16_f16 uZ;
|
|
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
signA = signF16UI( uiA );
|
|
expA = expF16UI( uiA );
|
|
sigA = fracF16UI( uiA );
|
|
signB = signF16UI( uiB );
|
|
expB = expF16UI( uiB );
|
|
sigB = fracF16UI( uiB );
|
|
signC = signF16UI( uiC ) ^ (op == softfloat_mulAdd_subC);
|
|
expC = expF16UI( uiC );
|
|
sigC = fracF16UI( uiC );
|
|
signProd = signA ^ signB ^ (op == softfloat_mulAdd_subProd);
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
if ( expA == 0x1F ) {
|
|
if ( sigA || ((expB == 0x1F) && sigB) ) goto propagateNaN_ABC;
|
|
magBits = expB | sigB;
|
|
goto infProdArg;
|
|
}
|
|
if ( expB == 0x1F ) {
|
|
if ( sigB ) goto propagateNaN_ABC;
|
|
magBits = expA | sigA;
|
|
goto infProdArg;
|
|
}
|
|
if ( expC == 0x1F ) {
|
|
if ( sigC ) {
|
|
uiZ = 0;
|
|
goto propagateNaN_ZC;
|
|
}
|
|
uiZ = uiC;
|
|
goto uiZ;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
if ( ! expA ) {
|
|
if ( ! sigA ) goto zeroProd;
|
|
normExpSig = softfloat_normSubnormalF16Sig( sigA );
|
|
expA = normExpSig.exp;
|
|
sigA = normExpSig.sig;
|
|
}
|
|
if ( ! expB ) {
|
|
if ( ! sigB ) goto zeroProd;
|
|
normExpSig = softfloat_normSubnormalF16Sig( sigB );
|
|
expB = normExpSig.exp;
|
|
sigB = normExpSig.sig;
|
|
}
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
expProd = expA + expB - 0xE;
|
|
sigA = (sigA | 0x0400)<<4;
|
|
sigB = (sigB | 0x0400)<<4;
|
|
sigProd = (uint_fast32_t) sigA * sigB;
|
|
if ( sigProd < 0x20000000 ) {
|
|
--expProd;
|
|
sigProd <<= 1;
|
|
}
|
|
signZ = signProd;
|
|
if ( ! expC ) {
|
|
if ( ! sigC ) {
|
|
expZ = expProd - 1;
|
|
sigZ = sigProd>>15 | ((sigProd & 0x7FFF) != 0);
|
|
goto roundPack;
|
|
}
|
|
normExpSig = softfloat_normSubnormalF16Sig( sigC );
|
|
expC = normExpSig.exp;
|
|
sigC = normExpSig.sig;
|
|
}
|
|
sigC = (sigC | 0x0400)<<3;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
expDiff = expProd - expC;
|
|
if ( signProd == signC ) {
|
|
/*--------------------------------------------------------------------
|
|
*--------------------------------------------------------------------*/
|
|
if ( expDiff <= 0 ) {
|
|
expZ = expC;
|
|
sigZ = sigC + softfloat_shiftRightJam32( sigProd, 16 - expDiff );
|
|
} else {
|
|
expZ = expProd;
|
|
sig32Z =
|
|
sigProd
|
|
+ softfloat_shiftRightJam32(
|
|
(uint_fast32_t) sigC<<16, expDiff );
|
|
sigZ = sig32Z>>16 | ((sig32Z & 0xFFFF) != 0 );
|
|
}
|
|
if ( sigZ < 0x4000 ) {
|
|
--expZ;
|
|
sigZ <<= 1;
|
|
}
|
|
} else {
|
|
/*--------------------------------------------------------------------
|
|
*--------------------------------------------------------------------*/
|
|
sig32C = (uint_fast32_t) sigC<<16;
|
|
if ( expDiff < 0 ) {
|
|
signZ = signC;
|
|
expZ = expC;
|
|
sig32Z = sig32C - softfloat_shiftRightJam32( sigProd, -expDiff );
|
|
} else if ( ! expDiff ) {
|
|
expZ = expProd;
|
|
sig32Z = sigProd - sig32C;
|
|
if ( ! sig32Z ) goto completeCancellation;
|
|
if ( sig32Z & 0x80000000 ) {
|
|
signZ = ! signZ;
|
|
sig32Z = -sig32Z;
|
|
}
|
|
} else {
|
|
expZ = expProd;
|
|
sig32Z = sigProd - softfloat_shiftRightJam32( sig32C, expDiff );
|
|
}
|
|
shiftDist = softfloat_countLeadingZeros32( sig32Z ) - 1;
|
|
expZ -= shiftDist;
|
|
shiftDist -= 16;
|
|
if ( shiftDist < 0 ) {
|
|
sigZ =
|
|
sig32Z>>(-shiftDist)
|
|
| ((uint32_t) (sig32Z<<(shiftDist & 31)) != 0);
|
|
} else {
|
|
sigZ = (uint_fast16_t) sig32Z<<shiftDist;
|
|
}
|
|
}
|
|
roundPack:
|
|
return softfloat_roundPackToF16( signZ, expZ, sigZ );
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
propagateNaN_ABC:
|
|
uiZ = softfloat_propagateNaNF16UI( uiA, uiB );
|
|
goto propagateNaN_ZC;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
infProdArg:
|
|
if ( magBits ) {
|
|
uiZ = packToF16UI( signProd, 0x1F, 0 );
|
|
if ( expC != 0x1F ) goto uiZ;
|
|
if ( sigC ) goto propagateNaN_ZC;
|
|
if ( signProd == signC ) goto uiZ;
|
|
}
|
|
softfloat_raiseFlags( softfloat_flag_invalid );
|
|
uiZ = defaultNaNF16UI;
|
|
propagateNaN_ZC:
|
|
uiZ = softfloat_propagateNaNF16UI( uiZ, uiC );
|
|
goto uiZ;
|
|
/*------------------------------------------------------------------------
|
|
*------------------------------------------------------------------------*/
|
|
zeroProd:
|
|
uiZ = uiC;
|
|
if ( ! (expC | sigC) && (signProd != signC) ) {
|
|
completeCancellation:
|
|
uiZ =
|
|
packToF16UI(
|
|
(softfloat_roundingMode == softfloat_round_min), 0, 0 );
|
|
}
|
|
uiZ:
|
|
uZ.ui = uiZ;
|
|
return uZ.f;
|
|
|
|
}
|
|
|