softfloat/s_roundPackToUI32.c


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// See LICENSE.SoftFloat for license details.


#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "internals.h"
#include "softfloat.h"

uint_fast32_t
 softfloat_roundPackToUI32(
     bool sign, uint_fast64_t sig, int_fast8_t roundingMode, bool exact )
{
    bool roundNearestEven;
    int roundIncrement, roundBits;
    uint_fast32_t z;

    roundNearestEven = ( roundingMode == softfloat_round_nearest_even );
    roundIncrement = 0x40;
    if (
           ! roundNearestEven
        && ( roundingMode != softfloat_round_nearest_maxMag )
    ) {
        roundIncrement =
               ( roundingMode == softfloat_round_minMag )
            || ( roundingMode
                     == ( sign ? softfloat_round_max : softfloat_round_min ) )
                ? 0
                : 0x7F;
    }
    roundBits = sig & 0x7F;
    sig += roundIncrement;
    if ( sig & UINT64_C( 0xFFFFFF8000000000 ) ) goto invalid;
    z = sig>>7;
    z &= ~ ( ! ( roundBits ^ 0x40 ) & roundNearestEven );
    if ( sign && z ) goto invalid;
    if ( exact && roundBits ) {
        softfloat_raiseFlags( softfloat_flag_inexact );
    }
    return z;
 invalid:
    softfloat_raiseFlags( softfloat_flag_invalid );
    return 0xFFFFFFFF;

}