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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_subMagsF64( uint_fast64_t uiA, uint_fast64_t uiB, bool signZ )
{
int_fast16_t expA;
uint_fast64_t sigA;
int_fast16_t expB;
uint_fast64_t sigB;
int_fast16_t expDiff;
uint_fast64_t uiZ;
int_fast16_t expZ;
uint_fast64_t sigZ;
union ui64_f64 uZ;
expA = expF64UI( uiA );
sigA = fracF64UI( uiA );
expB = expF64UI( uiB );
sigB = fracF64UI( uiB );
expDiff = expA - expB;
sigA <<= 10;
sigB <<= 10;
if ( 0 < expDiff ) goto expABigger;
if ( expDiff < 0 ) goto expBBigger;
if ( expA == 0x7FF ) {
if ( sigA | sigB ) goto propagateNaN;
softfloat_raiseFlags( softfloat_flag_invalid );
uiZ = defaultNaNF64UI;
goto uiZ;
}
if ( ! expA ) {
expA = 1;
expB = 1;
}
if ( sigB < sigA ) goto aBigger;
if ( sigA < sigB ) goto bBigger;
uiZ = packToF64UI( softfloat_roundingMode == softfloat_round_min, 0, 0 );
goto uiZ;
expBBigger:
if ( expB == 0x7FF ) {
if ( sigB ) goto propagateNaN;
uiZ = packToF64UI( signZ ^ 1, 0x7FF, 0 );
goto uiZ;
}
sigA += expA ? UINT64_C( 0x4000000000000000 ) : sigA;
sigA = softfloat_shift64RightJam( sigA, - expDiff );
sigB |= UINT64_C( 0x4000000000000000 );
bBigger:
signZ ^= 1;
expZ = expB;
sigZ = sigB - sigA;
goto normRoundPack;
expABigger:
if ( expA == 0x7FF ) {
if ( sigA ) goto propagateNaN;
uiZ = uiA;
goto uiZ;
}
sigB += expB ? UINT64_C( 0x4000000000000000 ) : sigB;
sigB = softfloat_shift64RightJam( sigB, expDiff );
sigA |= UINT64_C( 0x4000000000000000 );
aBigger:
expZ = expA;
sigZ = sigA - sigB;
normRoundPack:
return softfloat_normRoundPackToF64( signZ, expZ - 1, sigZ );
propagateNaN:
uiZ = softfloat_propagateNaNF64UI( uiA, uiB );
uiZ:
uZ.ui = uiZ;
return uZ.f;
}
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