s_normRoundPackToF64.c

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/*============================================================================
 
This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
Package, Release 3e, by John R. Hauser.
 
Copyright 2011, 2012, 2013, 2014, 2015, 2016 The Regents of the University of
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    this list of conditions, and the following disclaimer.
 
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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 shiftDist;
    union ui64_f64 uZ;
 
    shiftDist = softfloat_countLeadingZeros64( sig ) - 1;
    exp -= shiftDist;
    if ( (10 <= shiftDist) && ((unsigned int) exp < 0x7FD) ) {
        uZ.ui = packToF64UI( sign, sig ? exp : 0, sig<<(shiftDist - 10) );
        return uZ.f;
    } else {
        return softfloat_roundPackToF64( sign, exp, sig<<shiftDist );
    }
 
}