source/s_normRoundPackToF64.c

/*============================================================================

This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
Package, Release 3, by John R. Hauser.

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(Regents).  All Rights Reserved.  Redistribution and use in source and binary
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Redistributions of source code must retain the above copyright notice,
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=============================================================================*/

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

float64_t
 softfloat_normRoundPackToF64( bool sign, int_fast16_t exp, uint_fast64_t sig )
{
    int_fast8_t shiftCount;
    union ui64_f64 uZ;

    shiftCount = softfloat_countLeadingZeros64( sig ) - 1;
    exp -= shiftCount;
    if ( (10 <= shiftCount) && ((uint16_t) exp < 0x7FD) ) {
        uZ.ui = packToF64UI( sign, sig ? exp : 0, sig<<(shiftCount - 10) );
        return uZ.f;
    } else {
        return softfloat_roundPackToF64( sign, exp, sig<<shiftCount );
    }

}