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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 "softfloat.h"
float64_t
softfloat_roundPackToF64( bool sign, int_fast16_t exp, uint_fast64_t sig )
{
int roundingMode;
bool roundNearestEven;
int roundIncrement, roundBits;
bool isTiny;
uint_fast64_t uiZ;
union ui64_f64 uZ;
roundingMode = softfloat_roundingMode;
roundNearestEven = ( roundingMode == softfloat_round_nearest_even );
roundIncrement = 0x200;
if (
! roundNearestEven
&& ( roundingMode != softfloat_round_nearest_maxMag )
) {
roundIncrement =
( roundingMode == softfloat_round_minMag )
|| ( roundingMode
== ( sign ? softfloat_round_max : softfloat_round_min ) )
? 0
: 0x3FF;
}
roundBits = sig & 0x3FF;
if ( 0x7FD <= (uint16_t) exp ) {
if ( exp < 0 ) {
isTiny =
( softfloat_detectTininess
== softfloat_tininess_beforeRounding )
|| ( exp < -1 )
|| ( sig + roundIncrement < UINT64_C( 0x8000000000000000 ) );
sig = softfloat_shift64RightJam( sig, - exp );
exp = 0;
roundBits = sig & 0x3FF;
if ( isTiny && roundBits ) {
softfloat_raiseFlags( softfloat_flag_underflow );
}
} else if (
( 0x7FD < exp )
|| ( UINT64_C( 0x8000000000000000 ) <= sig + roundIncrement )
) {
softfloat_raiseFlags(
softfloat_flag_overflow | softfloat_flag_inexact );
uiZ = packToF64UI( sign, 0x7FF, 0 ) - ! roundIncrement;
goto uiZ;
}
}
if ( roundBits ) softfloat_raiseFlags( softfloat_flag_inexact );
sig = ( sig + roundIncrement )>>10;
sig &= ~ ( ! ( roundBits ^ 0x200 ) & roundNearestEven );
uiZ = packToF64UI( sign, sig ? exp : 0, sig );
uiZ:
uZ.ui = uiZ;
return uZ.f;
}
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