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// See LICENSE.SoftFloat for license details.
#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "primitives.h"
#include "internals.h"
#include "specialize.h"
#include "softfloat.h"
float64_t
softfloat_mulAddF64(
int op, uint_fast64_t uiA, uint_fast64_t uiB, uint_fast64_t uiC )
{
bool signA;
int_fast16_t expA;
uint_fast64_t sigA;
bool signB;
int_fast16_t expB;
uint_fast64_t sigB;
bool signC;
int_fast16_t expC;
uint_fast64_t sigC;
bool signProd;
uint_fast64_t magBits, uiZ;
struct exp16_sig64 normExpSig;
int_fast16_t expProd;
struct uint128 sigProd;
bool signZ;
int_fast16_t expZ;
uint_fast64_t sigZ;
int_fast16_t expDiff;
struct uint128 sigC128, sigZ128;
int shiftCount;
union ui64_f64 uZ;
signA = signF64UI( uiA );
expA = expF64UI( uiA );
sigA = fracF64UI( uiA );
signB = signF64UI( uiB );
expB = expF64UI( uiB );
sigB = fracF64UI( uiB );
signC = signF64UI( uiC ) ^ (( op & softfloat_mulAdd_subC ) != 0);
expC = expF64UI( uiC );
sigC = fracF64UI( uiC );
signProd = signA ^ signB ^ ( ( op & softfloat_mulAdd_subProd ) != 0);
if ( expA == 0x7FF ) {
if ( sigA || ( ( expB == 0x7FF ) && sigB ) ) goto propagateNaN_ABC;
magBits = expB | sigB;
goto infProdArg;
}
if ( expB == 0x7FF ) {
if ( sigB ) goto propagateNaN_ABC;
magBits = expA | sigA;
goto infProdArg;
}
if ( expC == 0x7FF ) {
if ( sigC ) {
uiZ = 0;
goto propagateNaN_ZC;
}
uiZ = uiC;
goto uiZ;
}
if ( ! expA ) {
if ( ! sigA ) goto zeroProd;
normExpSig = softfloat_normSubnormalF64Sig( sigA );
expA = normExpSig.exp;
sigA = normExpSig.sig;
}
if ( ! expB ) {
if ( ! sigB ) goto zeroProd;
normExpSig = softfloat_normSubnormalF64Sig( sigB );
expB = normExpSig.exp;
sigB = normExpSig.sig;
}
expProd = expA + expB - 0x3FE;
sigA = ( sigA | UINT64_C( 0x0010000000000000 ) )<<10;
sigB = ( sigB | UINT64_C( 0x0010000000000000 ) )<<10;
sigProd = softfloat_mul64To128( sigA, sigB );
if ( sigProd.v64 < UINT64_C( 0x2000000000000000 ) ) {
--expProd;
sigProd = softfloat_shortShift128Left( sigProd.v64, sigProd.v0, 1 );
}
signZ = signProd;
if ( ! expC ) {
if ( ! sigC ) {
expZ = expProd - 1;
sigZ = sigProd.v64<<1 | ( sigProd.v0 != 0 );
goto roundPack;
}
normExpSig = softfloat_normSubnormalF64Sig( sigC );
expC = normExpSig.exp;
sigC = normExpSig.sig;
}
sigC = ( sigC | UINT64_C( 0x0010000000000000 ) )<<9;
expDiff = expProd - expC;
if ( signProd == signC ) {
if ( expDiff <= 0 ) {
expZ = expC;
if ( expDiff ) {
sigProd.v64 =
softfloat_shift64RightJam( sigProd.v64, - expDiff );
}
sigZ = ( sigC + sigProd.v64 ) | ( sigProd.v0 != 0 );
} else {
expZ = expProd;
sigC128 = softfloat_shift128RightJam( sigC, 0, expDiff );
sigZ128 =
softfloat_add128(
sigProd.v64, sigProd.v0, sigC128.v64, sigC128.v0 );
sigZ = sigZ128.v64 | ( sigZ128.v0 != 0 );
}
if ( sigZ < UINT64_C( 0x4000000000000000 ) ) {
--expZ;
sigZ <<= 1;
}
} else {
/*** OPTIMIZE BETTER? ***/
if ( expDiff < 0 ) {
signZ = signC;
expZ = expC;
sigProd =
softfloat_shift128RightJam(
sigProd.v64, sigProd.v0, - expDiff );
sigZ128 = softfloat_sub128( sigC, 0, sigProd.v64, sigProd.v0 );
} else if ( ! expDiff ) {
expZ = expProd;
sigZ128 = softfloat_sub128( sigProd.v64, sigProd.v0, sigC, 0 );
if ( ! ( sigZ128.v64 | sigZ128.v0 ) ) goto completeCancellation;
if ( sigZ128.v64 & UINT64_C( 0x8000000000000000 ) ) {
signZ ^= 1;
sigZ128 = softfloat_sub128( 0, 0, sigZ128.v64, sigZ128.v0 );
}
} else {
expZ = expProd;
sigC128 = softfloat_shift128RightJam( sigC, 0, expDiff );
sigZ128 =
softfloat_sub128(
sigProd.v64, sigProd.v0, sigC128.v64, sigC128.v0 );
}
if ( ! sigZ128.v64 ) {
expZ -= 64;
sigZ128.v64 = sigZ128.v0;
sigZ128.v0 = 0;
}
shiftCount = softfloat_countLeadingZeros64( sigZ128.v64 ) - 1;
expZ -= shiftCount;
if ( shiftCount < 0 ) {
sigZ = softfloat_shortShift64RightJam( sigZ128.v64, - shiftCount );
} else {
sigZ128 =
softfloat_shortShift128Left(
sigZ128.v64, sigZ128.v0, shiftCount );
sigZ = sigZ128.v64;
}
sigZ |= ( sigZ128.v0 != 0 );
}
roundPack:
return softfloat_roundPackToF64( signZ, expZ, sigZ );
propagateNaN_ABC:
uiZ = softfloat_propagateNaNF64UI( uiA, uiB );
goto propagateNaN_ZC;
infProdArg:
if ( magBits ) {
uiZ = packToF64UI( signProd, 0x7FF, 0 );
if ( expC != 0x7FF ) goto uiZ;
if ( sigC ) goto propagateNaN_ZC;
if ( signProd == signC ) goto uiZ;
}
invalid:
softfloat_raiseFlags( softfloat_flag_invalid );
uiZ = defaultNaNF64UI;
propagateNaN_ZC:
uiZ = softfloat_propagateNaNF64UI( uiZ, uiC );
goto uiZ;
zeroProd:
uiZ = uiC;
if ( ! ( expC | sigC ) && ( signProd != signC ) ) {
completeCancellation:
uiZ =
packToF64UI( softfloat_roundingMode == softfloat_round_min, 0, 0 );
}
uiZ:
uZ.ui = uiZ;
return uZ.f;
}
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