[sim] added SoftFloat-3 source

[riscv-isa-sim.git] / softfloat / SoftFloat-3 / source / OLD-softfloat.c

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

This C source file is part of the SoftFloat IEC/IEEE Floating-point Arithmetic
Package, Release 2b.

Written by John R. Hauser.  This work was made possible in part by the
International Computer Science Institute, located at Suite 600, 1947 Center
Street, Berkeley, California 94704.  Funding was partially provided by the
National Science Foundation under grant MIP-9311980.  The original version
of this code was written as part of a project to build a fixed-point vector
processor in collaboration with the University of California at Berkeley,
overseen by Profs. Nelson Morgan and John Wawrzynek.  More information
is available through the Web page `http://www.cs.berkeley.edu/~jhauser/
arithmetic/SoftFloat.html'.

THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort has
been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT TIMES
RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO PERSONS
AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ALL LOSSES,
COSTS, OR OTHER PROBLEMS THEY INCUR DUE TO THE SOFTWARE, AND WHO FURTHERMORE
EFFECTIVELY INDEMNIFY JOHN HAUSER AND THE INTERNATIONAL COMPUTER SCIENCE
INSTITUTE (possibly via similar legal warning) AGAINST ALL LOSSES, COSTS, OR
OTHER PROBLEMS INCURRED BY THEIR CUSTOMERS AND CLIENTS DUE TO THE SOFTWARE.

Derivative works are acceptable, even for commercial purposes, so long as
(1) the source code for the derivative work includes prominent notice that
the work is derivative, and (2) the source code includes prominent notice with
these four paragraphs for those parts of this code that are retained.

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

#include "milieu.h"
#include "softfloat.h"

/*----------------------------------------------------------------------------
| Primitive arithmetic functions, including multi-word arithmetic, and
| division and square root approximations.  (Can be specialized to target if
| desired.)
*----------------------------------------------------------------------------*/
#include "softfloat-macros"

/*----------------------------------------------------------------------------
| Functions and definitions to determine:  (1) whether tininess for underflow
| is detected before or after rounding by default, (2) what (if anything)
| happens when exceptions are raised, (3) how signaling NaNs are distinguished
| from quiet NaNs, (4) the default generated quiet NaNs, and (5) how NaNs
| are propagated from function inputs to output.  These details are target-
| specific.
*----------------------------------------------------------------------------*/
#include "softfloat-specialize"

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the fraction bits of the extended double-precision floating-point
| value `a'.
*----------------------------------------------------------------------------*/

INLINE bits64 extractFloatx80Frac( floatx80 a )
{

    return a.low;

}

/*----------------------------------------------------------------------------
| Returns the exponent bits of the extended double-precision floating-point
| value `a'.
*----------------------------------------------------------------------------*/

INLINE int32 extractFloatx80Exp( floatx80 a )
{

    return a.high & 0x7FFF;

}

/*----------------------------------------------------------------------------
| Returns the sign bit of the extended double-precision floating-point value
| `a'.
*----------------------------------------------------------------------------*/

INLINE flag extractFloatx80Sign( floatx80 a )
{

    return a.high>>15;

}

/*----------------------------------------------------------------------------
| Normalizes the subnormal extended double-precision floating-point value
| represented by the denormalized significand `aSig'.  The normalized exponent
| and significand are stored at the locations pointed to by `zExpPtr' and
| `zSigPtr', respectively.
*----------------------------------------------------------------------------*/

static void
 normalizeFloatx80Subnormal( bits64 aSig, int32 *zExpPtr, bits64 *zSigPtr )
{
    int8 shiftCount;

    shiftCount = countLeadingZeros64( aSig );
    *zSigPtr = aSig<<shiftCount;
    *zExpPtr = 1 - shiftCount;

}

/*----------------------------------------------------------------------------
| Packs the sign `zSign', exponent `zExp', and significand `zSig' into an
| extended double-precision floating-point value, returning the result.
*----------------------------------------------------------------------------*/

INLINE floatx80 packFloatx80( flag zSign, int32 zExp, bits64 zSig )
{
    floatx80 z;

    z.low = zSig;
    z.high = ( ( (bits16) zSign )<<15 ) + zExp;
    return z;

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and extended significand formed by the concatenation of `zSig0' and `zSig1',
| and returns the proper extended double-precision floating-point value
| corresponding to the abstract input.  Ordinarily, the abstract value is
| rounded and packed into the extended double-precision format, with the
| inexact exception raised if the abstract input cannot be represented
| exactly.  However, if the abstract value is too large, the overflow and
| inexact exceptions are raised and an infinity or maximal finite value is
| returned.  If the abstract value is too small, the input value is rounded to
| a subnormal number, and the underflow and inexact exceptions are raised if
| the abstract input cannot be represented exactly as a subnormal extended
| double-precision floating-point number.
|     If `roundingPrecision' is 32 or 64, the result is rounded to the same
| number of bits as single or double precision, respectively.  Otherwise, the
| result is rounded to the full precision of the extended double-precision
| format.
|     The input significand must be normalized or smaller.  If the input
| significand is not normalized, `zExp' must be 0; in that case, the result
| returned is a subnormal number, and it must not require rounding.  The
| handling of underflow and overflow follows the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static floatx80
 roundAndPackFloatx80(
     int8 roundingPrecision, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1
 )
{
    int8 roundingMode;
    flag roundNearestEven, increment, isTiny;
    int64 roundIncrement, roundMask, roundBits;

    roundingMode = float_rounding_mode;
    roundNearestEven = ( roundingMode == float_round_nearest_even );
    if ( roundingPrecision == 80 ) goto precision80;
    if ( roundingPrecision == 64 ) {
        roundIncrement = LIT64( 0x0000000000000400 );
        roundMask = LIT64( 0x00000000000007FF );
    }
    else if ( roundingPrecision == 32 ) {
        roundIncrement = LIT64( 0x0000008000000000 );
        roundMask = LIT64( 0x000000FFFFFFFFFF );
    }
    else {
        goto precision80;
    }
    zSig0 |= ( zSig1 != 0 );
    if ( ! roundNearestEven ) {
        if ( roundingMode == float_round_to_zero ) {
            roundIncrement = 0;
        }
        else {
            roundIncrement = roundMask;
            if ( zSign ) {
                if ( roundingMode == float_round_up ) roundIncrement = 0;
            }
            else {
                if ( roundingMode == float_round_down ) roundIncrement = 0;
            }
        }
    }
    roundBits = zSig0 & roundMask;
    if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) {
        if (    ( 0x7FFE < zExp )
             || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) )
           ) {
            goto overflow;
        }
        if ( zExp <= 0 ) {
            isTiny =
                   ( float_detect_tininess == float_tininess_before_rounding )
                || ( zExp < 0 )
                || ( zSig0 <= zSig0 + roundIncrement );
            shift64RightJamming( zSig0, 1 - zExp, &zSig0 );
            zExp = 0;
            roundBits = zSig0 & roundMask;
            if ( isTiny && roundBits ) float_raise( float_flag_underflow );
            if ( roundBits ) float_exception_flags |= float_flag_inexact;
            zSig0 += roundIncrement;
            if ( (sbits64) zSig0 < 0 ) zExp = 1;
            roundIncrement = roundMask + 1;
            if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
                roundMask |= roundIncrement;
            }
            zSig0 &= ~ roundMask;
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
    if ( roundBits ) float_exception_flags |= float_flag_inexact;
    zSig0 += roundIncrement;
    if ( zSig0 < roundIncrement ) {
        ++zExp;
        zSig0 = LIT64( 0x8000000000000000 );
    }
    roundIncrement = roundMask + 1;
    if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
        roundMask |= roundIncrement;
    }
    zSig0 &= ~ roundMask;
    if ( zSig0 == 0 ) zExp = 0;
    return packFloatx80( zSign, zExp, zSig0 );
 precision80:
    increment = ( (sbits64) zSig1 < 0 );
    if ( ! roundNearestEven ) {
        if ( roundingMode == float_round_to_zero ) {
            increment = 0;
        }
        else {
            if ( zSign ) {
                increment = ( roundingMode == float_round_down ) && zSig1;
            }
            else {
                increment = ( roundingMode == float_round_up ) && zSig1;
            }
        }
    }
    if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) {
        if (    ( 0x7FFE < zExp )
             || (    ( zExp == 0x7FFE )
                  && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) )
                  && increment
                )
           ) {
            roundMask = 0;
 overflow:
            float_raise( float_flag_overflow | float_flag_inexact );
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
               ) {
                return packFloatx80( zSign, 0x7FFE, ~ roundMask );
            }
            return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
        }
        if ( zExp <= 0 ) {
            isTiny =
                   ( float_detect_tininess == float_tininess_before_rounding )
                || ( zExp < 0 )
                || ! increment
                || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) );
            shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 );
            zExp = 0;
            if ( isTiny && zSig1 ) float_raise( float_flag_underflow );
            if ( zSig1 ) float_exception_flags |= float_flag_inexact;
            if ( roundNearestEven ) {
                increment = ( (sbits64) zSig1 < 0 );
            }
            else {
                if ( zSign ) {
                    increment = ( roundingMode == float_round_down ) && zSig1;
                }
                else {
                    increment = ( roundingMode == float_round_up ) && zSig1;
                }
            }
            if ( increment ) {
                ++zSig0;
                zSig0 &=
                    ~ ( ( (bits64) ( zSig1<<1 ) == 0 ) & roundNearestEven );
                if ( (sbits64) zSig0 < 0 ) zExp = 1;
            }
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
    if ( zSig1 ) float_exception_flags |= float_flag_inexact;
    if ( increment ) {
        ++zSig0;
        if ( zSig0 == 0 ) {
            ++zExp;
            zSig0 = LIT64( 0x8000000000000000 );
        }
        else {
            zSig0 &= ~ ( ( (bits64) ( zSig1<<1 ) == 0 ) & roundNearestEven );
        }
    }
    else {
        if ( zSig0 == 0 ) zExp = 0;
    }
    return packFloatx80( zSign, zExp, zSig0 );

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent
| `zExp', and significand formed by the concatenation of `zSig0' and `zSig1',
| and returns the proper extended double-precision floating-point value
| corresponding to the abstract input.  This routine is just like
| `roundAndPackFloatx80' except that the input significand does not have to be
| normalized.
*----------------------------------------------------------------------------*/

static floatx80
 normalizeRoundAndPackFloatx80(
     int8 roundingPrecision, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1
 )
{
    int8 shiftCount;

    if ( zSig0 == 0 ) {
        zSig0 = zSig1;
        zSig1 = 0;
        zExp -= 64;
    }
    shiftCount = countLeadingZeros64( zSig0 );
    shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 );
    zExp -= shiftCount;
    return
        roundAndPackFloatx80( roundingPrecision, zSign, zExp, zSig0, zSig1 );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the least-significant 64 fraction bits of the quadruple-precision
| floating-point value `a'.
*----------------------------------------------------------------------------*/

INLINE bits64 extractFloat128Frac1( float128 a )
{

    return a.low;

}

/*----------------------------------------------------------------------------
| Returns the most-significant 48 fraction bits of the quadruple-precision
| floating-point value `a'.
*----------------------------------------------------------------------------*/

INLINE bits64 extractFloat128Frac0( float128 a )
{

    return a.high & LIT64( 0x0000FFFFFFFFFFFF );

}

/*----------------------------------------------------------------------------
| Returns the exponent bits of the quadruple-precision floating-point value
| `a'.
*----------------------------------------------------------------------------*/

INLINE int32 extractFloat128Exp( float128 a )
{

    return ( a.high>>48 ) & 0x7FFF;

}

/*----------------------------------------------------------------------------
| Returns the sign bit of the quadruple-precision floating-point value `a'.
*----------------------------------------------------------------------------*/

INLINE flag extractFloat128Sign( float128 a )
{

    return a.high>>63;

}

/*----------------------------------------------------------------------------
| Normalizes the subnormal quadruple-precision floating-point value
| represented by the denormalized significand formed by the concatenation of
| `aSig0' and `aSig1'.  The normalized exponent is stored at the location
| pointed to by `zExpPtr'.  The most significant 49 bits of the normalized
| significand are stored at the location pointed to by `zSig0Ptr', and the
| least significant 64 bits of the normalized significand are stored at the
| location pointed to by `zSig1Ptr'.
*----------------------------------------------------------------------------*/

static void
 normalizeFloat128Subnormal(
     bits64 aSig0,
     bits64 aSig1,
     int32 *zExpPtr,
     bits64 *zSig0Ptr,
     bits64 *zSig1Ptr
 )
{
    int8 shiftCount;

    if ( aSig0 == 0 ) {
        shiftCount = countLeadingZeros64( aSig1 ) - 15;
        if ( shiftCount < 0 ) {
            *zSig0Ptr = aSig1>>( - shiftCount );
            *zSig1Ptr = aSig1<<( shiftCount & 63 );
        }
        else {
            *zSig0Ptr = aSig1<<shiftCount;
            *zSig1Ptr = 0;
        }
        *zExpPtr = - shiftCount - 63;
    }
    else {
        shiftCount = countLeadingZeros64( aSig0 ) - 15;
        shortShift128Left( aSig0, aSig1, shiftCount, zSig0Ptr, zSig1Ptr );
        *zExpPtr = 1 - shiftCount;
    }

}

/*----------------------------------------------------------------------------
| Packs the sign `zSign', the exponent `zExp', and the significand formed
| by the concatenation of `zSig0' and `zSig1' into a quadruple-precision
| floating-point value, returning the result.  After being shifted into the
| proper positions, the three fields `zSign', `zExp', and `zSig0' are simply
| added together to form the most significant 32 bits of the result.  This
| means that any integer portion of `zSig0' will be added into the exponent.
| Since a properly normalized significand will have an integer portion equal
| to 1, the `zExp' input should be 1 less than the desired result exponent
| whenever `zSig0' and `zSig1' concatenated form a complete, normalized
| significand.
*----------------------------------------------------------------------------*/

INLINE float128
 packFloat128( flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 )
{
    float128 z;

    z.low = zSig1;
    z.high = ( ( (bits64) zSign )<<63 ) + ( ( (bits64) zExp )<<48 ) + zSig0;
    return z;

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and extended significand formed by the concatenation of `zSig0', `zSig1',
| and `zSig2', and returns the proper quadruple-precision floating-point value
| corresponding to the abstract input.  Ordinarily, the abstract value is
| simply rounded and packed into the quadruple-precision format, with the
| inexact exception raised if the abstract input cannot be represented
| exactly.  However, if the abstract value is too large, the overflow and
| inexact exceptions are raised and an infinity or maximal finite value is
| returned.  If the abstract value is too small, the input value is rounded to
| a subnormal number, and the underflow and inexact exceptions are raised if
| the abstract input cannot be represented exactly as a subnormal quadruple-
| precision floating-point number.
|     The input significand must be normalized or smaller.  If the input
| significand is not normalized, `zExp' must be 0; in that case, the result
| returned is a subnormal number, and it must not require rounding.  In the
| usual case that the input significand is normalized, `zExp' must be 1 less
| than the ``true'' floating-point exponent.  The handling of underflow and
| overflow follows the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static float128
 roundAndPackFloat128(
     flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1, bits64 zSig2 )
{
    int8 roundingMode;
    flag roundNearestEven, increment, isTiny;

    roundingMode = float_rounding_mode;
    roundNearestEven = ( roundingMode == float_round_nearest_even );
    increment = ( (sbits64) zSig2 < 0 );
    if ( ! roundNearestEven ) {
        if ( roundingMode == float_round_to_zero ) {
            increment = 0;
        }
        else {
            if ( zSign ) {
                increment = ( roundingMode == float_round_down ) && zSig2;
            }
            else {
                increment = ( roundingMode == float_round_up ) && zSig2;
            }
        }
    }
    if ( 0x7FFD <= (bits32) zExp ) {
        if (    ( 0x7FFD < zExp )
             || (    ( zExp == 0x7FFD )
                  && eq128(
                         LIT64( 0x0001FFFFFFFFFFFF ),
                         LIT64( 0xFFFFFFFFFFFFFFFF ),
                         zSig0,
                         zSig1
                     )
                  && increment
                )
           ) {
            float_raise( float_flag_overflow | float_flag_inexact );
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
               ) {
                return
                    packFloat128(
                        zSign,
                        0x7FFE,
                        LIT64( 0x0000FFFFFFFFFFFF ),
                        LIT64( 0xFFFFFFFFFFFFFFFF )
                    );
            }
            return packFloat128( zSign, 0x7FFF, 0, 0 );
        }
        if ( zExp < 0 ) {
            isTiny =
                   ( float_detect_tininess == float_tininess_before_rounding )
                || ( zExp < -1 )
                || ! increment
                || lt128(
                       zSig0,
                       zSig1,
                       LIT64( 0x0001FFFFFFFFFFFF ),
                       LIT64( 0xFFFFFFFFFFFFFFFF )
                   );
            shift128ExtraRightJamming(
                zSig0, zSig1, zSig2, - zExp, &zSig0, &zSig1, &zSig2 );
            zExp = 0;
            if ( isTiny && zSig2 ) float_raise( float_flag_underflow );
            if ( roundNearestEven ) {
                increment = ( (sbits64) zSig2 < 0 );
            }
            else {
                if ( zSign ) {
                    increment = ( roundingMode == float_round_down ) && zSig2;
                }
                else {
                    increment = ( roundingMode == float_round_up ) && zSig2;
                }
            }
        }
    }
    if ( zSig2 ) float_exception_flags |= float_flag_inexact;
    if ( increment ) {
        add128( zSig0, zSig1, 0, 1, &zSig0, &zSig1 );
        zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven );
    }
    else {
        if ( ( zSig0 | zSig1 ) == 0 ) zExp = 0;
    }
    return packFloat128( zSign, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand formed by the concatenation of `zSig0' and `zSig1', and
| returns the proper quadruple-precision floating-point value corresponding
| to the abstract input.  This routine is just like `roundAndPackFloat128'
| except that the input significand has fewer bits and does not have to be
| normalized.  In all cases, `zExp' must be 1 less than the ``true'' floating-
| point exponent.
*----------------------------------------------------------------------------*/

static float128
 normalizeRoundAndPackFloat128(
     flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 )
{
    int8 shiftCount;
    bits64 zSig2;

    if ( zSig0 == 0 ) {
        zSig0 = zSig1;
        zSig1 = 0;
        zExp -= 64;
    }
    shiftCount = countLeadingZeros64( zSig0 ) - 15;
    if ( 0 <= shiftCount ) {
        zSig2 = 0;
        shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 );
    }
    else {
        shift128ExtraRightJamming(
            zSig0, zSig1, 0, - shiftCount, &zSig0, &zSig1, &zSig2 );
    }
    zExp -= shiftCount;
    return roundAndPackFloat128( zSign, zExp, zSig0, zSig1, zSig2 );

}

#endif

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the 32-bit two's complement integer `a'
| to the extended double-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 int32_to_floatx80( int32 a )
{
    flag zSign;
    uint32 absA;
    int8 shiftCount;
    bits64 zSig;

    if ( a == 0 ) return packFloatx80( 0, 0, 0 );
    zSign = ( a < 0 );
    absA = zSign ? - a : a;
    shiftCount = countLeadingZeros32( absA ) + 32;
    zSig = absA;
    return packFloatx80( zSign, 0x403E - shiftCount, zSig<<shiftCount );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the 32-bit two's complement integer `a' to
| the quadruple-precision floating-point format.  The conversion is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 int32_to_float128( int32 a )
{
    flag zSign;
    uint32 absA;
    int8 shiftCount;
    bits64 zSig0;

    if ( a == 0 ) return packFloat128( 0, 0, 0, 0 );
    zSign = ( a < 0 );
    absA = zSign ? - a : a;
    shiftCount = countLeadingZeros32( absA ) + 17;
    zSig0 = absA;
    return packFloat128( zSign, 0x402E - shiftCount, zSig0<<shiftCount, 0 );

}

#endif

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the 64-bit two's complement integer `a'
| to the extended double-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 int64_to_floatx80( int64 a )
{
    flag zSign;
    uint64 absA;
    int8 shiftCount;

    if ( a == 0 ) return packFloatx80( 0, 0, 0 );
    zSign = ( a < 0 );
    absA = zSign ? - a : a;
    shiftCount = countLeadingZeros64( absA );
    return packFloatx80( zSign, 0x403E - shiftCount, absA<<shiftCount );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the 64-bit two's complement integer `a' to
| the quadruple-precision floating-point format.  The conversion is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 int64_to_float128( int64 a )
{
    flag zSign;
    uint64 absA;
    int8 shiftCount;
    int32 zExp;
    bits64 zSig0, zSig1;

    if ( a == 0 ) return packFloat128( 0, 0, 0, 0 );
    zSign = ( a < 0 );
    absA = zSign ? - a : a;
    shiftCount = countLeadingZeros64( absA ) + 49;
    zExp = 0x406E - shiftCount;
    if ( 64 <= shiftCount ) {
        zSig1 = 0;
        zSig0 = absA;
        shiftCount -= 64;
    }
    else {
        zSig1 = absA;
        zSig0 = 0;
    }
    shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 );
    return packFloat128( zSign, zExp, zSig0, zSig1 );

}

#endif

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the single-precision floating-point value
| `a' to the extended double-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 float32_to_floatx80( float32 a )
{
    flag aSign;
    int16 aExp;
    bits32 aSig;

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
        if ( aSig ) return commonNaNToFloatx80( float32ToCommonNaN( a ) );
        return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
    }
    aSig |= 0x00800000;
    return packFloatx80( aSign, aExp + 0x3F80, ( (bits64) aSig )<<40 );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the single-precision floating-point value
| `a' to the double-precision floating-point format.  The conversion is
| performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

float128 float32_to_float128( float32 a )
{
    flag aSign;
    int16 aExp;
    bits32 aSig;

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
        if ( aSig ) return commonNaNToFloat128( float32ToCommonNaN( a ) );
        return packFloat128( aSign, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
    return packFloat128( aSign, aExp + 0x3F80, ( (bits64) aSig )<<25, 0 );

}

#endif

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the double-precision floating-point value
| `a' to the extended double-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 float64_to_floatx80( float64 a )
{
    flag aSign;
    int16 aExp;
    bits64 aSig;

    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
        if ( aSig ) return commonNaNToFloatx80( float64ToCommonNaN( a ) );
        return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat64Subnormal( aSig, &aExp, &aSig );
    }
    return
        packFloatx80(
            aSign, aExp + 0x3C00, ( aSig | LIT64( 0x0010000000000000 ) )<<11 );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the double-precision floating-point value
| `a' to the quadruple-precision floating-point format.  The conversion is
| performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

float128 float64_to_float128( float64 a )
{
    flag aSign;
    int16 aExp;
    bits64 aSig, zSig0, zSig1;

    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
        if ( aSig ) return commonNaNToFloat128( float64ToCommonNaN( a ) );
        return packFloat128( aSign, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 );
        normalizeFloat64Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
    shift128Right( aSig, 0, 4, &zSig0, &zSig1 );
    return packFloat128( aSign, aExp + 0x3C00, zSig0, zSig1 );

}

#endif

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the 32-bit two's complement integer format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic---which means in particular that the conversion
| is rounded according to the current rounding mode.  If `a' is a NaN, the
| largest positive integer is returned.  Otherwise, if the conversion
| overflows, the largest integer with the same sign as `a' is returned.
*----------------------------------------------------------------------------*/

int32 floatx80_to_int32( floatx80 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0;
    shiftCount = 0x4037 - aExp;
    if ( shiftCount <= 0 ) shiftCount = 1;
    shift64RightJamming( aSig, shiftCount, &aSig );
    return roundAndPackInt32( aSign, aSig );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the 32-bit two's complement integer format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic, except that the conversion is always rounded
| toward zero.  If `a' is a NaN, the largest positive integer is returned.
| Otherwise, if the conversion overflows, the largest integer with the same
| sign as `a' is returned.
*----------------------------------------------------------------------------*/

int32 floatx80_to_int32_round_to_zero( floatx80 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig, savedASig;
    int32 z;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( 0x401E < aExp ) {
        if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0;
        goto invalid;
    }
    else if ( aExp < 0x3FFF ) {
        if ( aExp || aSig ) float_exception_flags |= float_flag_inexact;
        return 0;
    }
    shiftCount = 0x403E - aExp;
    savedASig = aSig;
    aSig >>= shiftCount;
    z = aSig;
    if ( aSign ) z = - z;
    if ( ( z < 0 ) ^ aSign ) {
 invalid:
        float_raise( float_flag_invalid );
        return aSign ? (sbits32) 0x80000000 : 0x7FFFFFFF;
    }
    if ( ( aSig<<shiftCount ) != savedASig ) {
        float_exception_flags |= float_flag_inexact;
    }
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the 64-bit two's complement integer format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic---which means in particular that the conversion
| is rounded according to the current rounding mode.  If `a' is a NaN,
| the largest positive integer is returned.  Otherwise, if the conversion
| overflows, the largest integer with the same sign as `a' is returned.
*----------------------------------------------------------------------------*/

int64 floatx80_to_int64( floatx80 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig, aSigExtra;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    shiftCount = 0x403E - aExp;
    if ( shiftCount <= 0 ) {
        if ( shiftCount ) {
            float_raise( float_flag_invalid );
            if (    ! aSign
                 || (    ( aExp == 0x7FFF )
                      && ( aSig != LIT64( 0x8000000000000000 ) ) )
               ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
            return (sbits64) LIT64( 0x8000000000000000 );
        }
        aSigExtra = 0;
    }
    else {
        shift64ExtraRightJamming( aSig, 0, shiftCount, &aSig, &aSigExtra );
    }
    return roundAndPackInt64( aSign, aSig, aSigExtra );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the 64-bit two's complement integer format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic, except that the conversion is always rounded
| toward zero.  If `a' is a NaN, the largest positive integer is returned.
| Otherwise, if the conversion overflows, the largest integer with the same
| sign as `a' is returned.
*----------------------------------------------------------------------------*/

int64 floatx80_to_int64_round_to_zero( floatx80 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig;
    int64 z;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    shiftCount = aExp - 0x403E;
    if ( 0 <= shiftCount ) {
        aSig &= LIT64( 0x7FFFFFFFFFFFFFFF );
        if ( ( a.high != 0xC03E ) || aSig ) {
            float_raise( float_flag_invalid );
            if ( ! aSign || ( ( aExp == 0x7FFF ) && aSig ) ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
        }
        return (sbits64) LIT64( 0x8000000000000000 );
    }
    else if ( aExp < 0x3FFF ) {
        if ( aExp | aSig ) float_exception_flags |= float_flag_inexact;
        return 0;
    }
    z = aSig>>( - shiftCount );
    if ( (bits64) ( aSig<<( shiftCount & 63 ) ) ) {
        float_exception_flags |= float_flag_inexact;
    }
    if ( aSign ) z = - z;
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the single-precision floating-point format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float32 floatx80_to_float32( floatx80 a )
{
    flag aSign;
    int32 aExp;
    bits64 aSig;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( aSig<<1 ) ) {
            return commonNaNToFloat32( floatx80ToCommonNaN( a ) );
        }
        return packFloat32( aSign, 0xFF, 0 );
    }
    shift64RightJamming( aSig, 33, &aSig );
    if ( aExp || aSig ) aExp -= 0x3F81;
    return roundAndPackFloat32( aSign, aExp, aSig );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the double-precision floating-point format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float64 floatx80_to_float64( floatx80 a )
{
    flag aSign;
    int32 aExp;
    bits64 aSig, zSig;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( aSig<<1 ) ) {
            return commonNaNToFloat64( floatx80ToCommonNaN( a ) );
        }
        return packFloat64( aSign, 0x7FF, 0 );
    }
    shift64RightJamming( aSig, 1, &zSig );
    if ( aExp || aSig ) aExp -= 0x3C01;
    return roundAndPackFloat64( aSign, aExp, zSig );

}

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the extended double-precision floating-
| point value `a' to the quadruple-precision floating-point format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 floatx80_to_float128( floatx80 a )
{
    flag aSign;
    int16 aExp;
    bits64 aSig, zSig0, zSig1;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) {
        return commonNaNToFloat128( floatx80ToCommonNaN( a ) );
    }
    shift128Right( aSig<<1, 0, 16, &zSig0, &zSig1 );
    return packFloat128( aSign, aExp, zSig0, zSig1 );

}

#endif

/*----------------------------------------------------------------------------
| Rounds the extended double-precision floating-point value `a' to an integer,
| and returns the result as an extended quadruple-precision floating-point
| value.  The operation is performed according to the IEC/IEEE Standard for
| Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_round_to_int( floatx80 a )
{
    flag aSign;
    int32 aExp;
    bits64 lastBitMask, roundBitsMask;
    int8 roundingMode;
    floatx80 z;

    aExp = extractFloatx80Exp( a );
    if ( 0x403E <= aExp ) {
        if ( ( aExp == 0x7FFF ) && (bits64) ( extractFloatx80Frac( a )<<1 ) ) {
            return propagateFloatx80NaN( a, a );
        }
        return a;
    }
    if ( aExp < 0x3FFF ) {
        if (    ( aExp == 0 )
             && ( (bits64) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) {
            return a;
        }
        float_exception_flags |= float_flag_inexact;
        aSign = extractFloatx80Sign( a );
        switch ( float_rounding_mode ) {
         case float_round_nearest_even:
            if ( ( aExp == 0x3FFE ) && (bits64) ( extractFloatx80Frac( a )<<1 )
               ) {
                return
                    packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) );
            }
            break;
         case float_round_down:
            return
                  aSign ?
                      packFloatx80( 1, 0x3FFF, LIT64( 0x8000000000000000 ) )
                : packFloatx80( 0, 0, 0 );
         case float_round_up:
            return
                  aSign ? packFloatx80( 1, 0, 0 )
                : packFloatx80( 0, 0x3FFF, LIT64( 0x8000000000000000 ) );
        }
        return packFloatx80( aSign, 0, 0 );
    }
    lastBitMask = 1;
    lastBitMask <<= 0x403E - aExp;
    roundBitsMask = lastBitMask - 1;
    z = a;
    roundingMode = float_rounding_mode;
    if ( roundingMode == float_round_nearest_even ) {
        z.low += lastBitMask>>1;
        if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask;
    }
    else if ( roundingMode != float_round_to_zero ) {
        if ( extractFloatx80Sign( z ) ^ ( roundingMode == float_round_up ) ) {
            z.low += roundBitsMask;
        }
    }
    z.low &= ~ roundBitsMask;
    if ( z.low == 0 ) {
        ++z.high;
        z.low = LIT64( 0x8000000000000000 );
    }
    if ( z.low != a.low ) float_exception_flags |= float_flag_inexact;
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of adding the absolute values of the extended double-
| precision floating-point values `a' and `b'.  If `zSign' is 1, the sum is
| negated before being returned.  `zSign' is ignored if the result is a NaN.
| The addition is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static floatx80 addFloatx80Sigs( floatx80 a, floatx80 b, flag zSign )
{
    int32 aExp, bExp, zExp;
    bits64 aSig, bSig, zSig0, zSig1;
    int32 expDiff;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    expDiff = aExp - bExp;
    if ( 0 < expDiff ) {
        if ( aExp == 0x7FFF ) {
            if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
            return a;
        }
        if ( bExp == 0 ) --expDiff;
        shift64ExtraRightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
        zExp = aExp;
    }
    else if ( expDiff < 0 ) {
        if ( bExp == 0x7FFF ) {
            if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
            return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
        }
        if ( aExp == 0 ) ++expDiff;
        shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
        zExp = bExp;
    }
    else {
        if ( aExp == 0x7FFF ) {
            if ( (bits64) ( ( aSig | bSig )<<1 ) ) {
                return propagateFloatx80NaN( a, b );
            }
            return a;
        }
        zSig1 = 0;
        zSig0 = aSig + bSig;
        if ( aExp == 0 ) {
            normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 );
            goto roundAndPack;
        }
        zExp = aExp;
        goto shiftRight1;
    }
    zSig0 = aSig + bSig;
    if ( (sbits64) zSig0 < 0 ) goto roundAndPack;
 shiftRight1:
    shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 );
    zSig0 |= LIT64( 0x8000000000000000 );
    ++zExp;
 roundAndPack:
    return
        roundAndPackFloatx80(
            floatx80_rounding_precision, zSign, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns the result of subtracting the absolute values of the extended
| double-precision floating-point values `a' and `b'.  If `zSign' is 1, the
| difference is negated before being returned.  `zSign' is ignored if the
| result is a NaN.  The subtraction is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static floatx80 subFloatx80Sigs( floatx80 a, floatx80 b, flag zSign )
{
    int32 aExp, bExp, zExp;
    bits64 aSig, bSig, zSig0, zSig1;
    int32 expDiff;
    floatx80 z;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    expDiff = aExp - bExp;
    if ( 0 < expDiff ) goto aExpBigger;
    if ( expDiff < 0 ) goto bExpBigger;
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( ( aSig | bSig )<<1 ) ) {
            return propagateFloatx80NaN( a, b );
        }
        float_raise( float_flag_invalid );
        z.low = floatx80_default_nan_low;
        z.high = floatx80_default_nan_high;
        return z;
    }
    if ( aExp == 0 ) {
        aExp = 1;
        bExp = 1;
    }
    zSig1 = 0;
    if ( bSig < aSig ) goto aBigger;
    if ( aSig < bSig ) goto bBigger;
    return packFloatx80( float_rounding_mode == float_round_down, 0, 0 );
 bExpBigger:
    if ( bExp == 0x7FFF ) {
        if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
        return packFloatx80( zSign ^ 1, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( aExp == 0 ) ++expDiff;
    shift128RightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
 bBigger:
    sub128( bSig, 0, aSig, zSig1, &zSig0, &zSig1 );
    zExp = bExp;
    zSign ^= 1;
    goto normalizeRoundAndPack;
 aExpBigger:
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
        return a;
    }
    if ( bExp == 0 ) --expDiff;
    shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
 aBigger:
    sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 );
    zExp = aExp;
 normalizeRoundAndPack:
    return
        normalizeRoundAndPackFloatx80(
            floatx80_rounding_precision, zSign, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns the result of adding the extended double-precision floating-point
| values `a' and `b'.  The operation is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_add( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
        return addFloatx80Sigs( a, b, aSign );
    }
    else {
        return subFloatx80Sigs( a, b, aSign );
    }

}

/*----------------------------------------------------------------------------
| Returns the result of subtracting the extended double-precision floating-
| point values `a' and `b'.  The operation is performed according to the
| IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_sub( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
        return subFloatx80Sigs( a, b, aSign );
    }
    else {
        return addFloatx80Sigs( a, b, aSign );
    }

}

/*----------------------------------------------------------------------------
| Returns the result of multiplying the extended double-precision floating-
| point values `a' and `b'.  The operation is performed according to the
| IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_mul( floatx80 a, floatx80 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, zExp;
    bits64 aSig, bSig, zSig0, zSig1;
    floatx80 z;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
        if (    (bits64) ( aSig<<1 )
             || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) {
            return propagateFloatx80NaN( a, b );
        }
        if ( ( bExp | bSig ) == 0 ) goto invalid;
        return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( bExp == 0x7FFF ) {
        if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
        if ( ( aExp | aSig ) == 0 ) {
 invalid:
            float_raise( float_flag_invalid );
            z.low = floatx80_default_nan_low;
            z.high = floatx80_default_nan_high;
            return z;
        }
        return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
        normalizeFloatx80Subnormal( aSig, &aExp, &aSig );
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) return packFloatx80( zSign, 0, 0 );
        normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
    }
    zExp = aExp + bExp - 0x3FFE;
    mul64To128( aSig, bSig, &zSig0, &zSig1 );
    if ( 0 < (sbits64) zSig0 ) {
        shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 );
        --zExp;
    }
    return
        roundAndPackFloatx80(
            floatx80_rounding_precision, zSign, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns the result of dividing the extended double-precision floating-point
| value `a' by the corresponding value `b'.  The operation is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_div( floatx80 a, floatx80 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, zExp;
    bits64 aSig, bSig, zSig0, zSig1;
    bits64 rem0, rem1, rem2, term0, term1, term2;
    floatx80 z;

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
        if ( bExp == 0x7FFF ) {
            if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
            goto invalid;
        }
        return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( bExp == 0x7FFF ) {
        if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
        return packFloatx80( zSign, 0, 0 );
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
            if ( ( aExp | aSig ) == 0 ) {
 invalid:
                float_raise( float_flag_invalid );
                z.low = floatx80_default_nan_low;
                z.high = floatx80_default_nan_high;
                return z;
            }
            float_raise( float_flag_divbyzero );
            return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
        }
        normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
        normalizeFloatx80Subnormal( aSig, &aExp, &aSig );
    }
    zExp = aExp - bExp + 0x3FFE;
    rem1 = 0;
    if ( bSig <= aSig ) {
        shift128Right( aSig, 0, 1, &aSig, &rem1 );
        ++zExp;
    }
    zSig0 = estimateDiv128To64( aSig, rem1, bSig );
    mul64To128( bSig, zSig0, &term0, &term1 );
    sub128( aSig, rem1, term0, term1, &rem0, &rem1 );
    while ( (sbits64) rem0 < 0 ) {
        --zSig0;
        add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
    }
    zSig1 = estimateDiv128To64( rem1, 0, bSig );
    if ( (bits64) ( zSig1<<1 ) <= 8 ) {
        mul64To128( bSig, zSig1, &term1, &term2 );
        sub128( rem1, 0, term1, term2, &rem1, &rem2 );
        while ( (sbits64) rem1 < 0 ) {
            --zSig1;
            add128( rem1, rem2, 0, bSig, &rem1, &rem2 );
        }
        zSig1 |= ( ( rem1 | rem2 ) != 0 );
    }
    return
        roundAndPackFloatx80(
            floatx80_rounding_precision, zSign, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns the remainder of the extended double-precision floating-point value
| `a' with respect to the corresponding value `b'.  The operation is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_rem( floatx80 a, floatx80 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, expDiff;
    bits64 aSig0, aSig1, bSig;
    bits64 q, term0, term1, alternateASig0, alternateASig1;
    floatx80 z;

    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    if ( aExp == 0x7FFF ) {
        if (    (bits64) ( aSig0<<1 )
             || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) {
            return propagateFloatx80NaN( a, b );
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
        if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
 invalid:
            float_raise( float_flag_invalid );
            z.low = floatx80_default_nan_low;
            z.high = floatx80_default_nan_high;
            return z;
        }
        normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
        if ( (bits64) ( aSig0<<1 ) == 0 ) return a;
        normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 );
    }
    bSig |= LIT64( 0x8000000000000000 );
    zSign = aSign;
    expDiff = aExp - bExp;
    aSig1 = 0;
    if ( expDiff < 0 ) {
        if ( expDiff < -1 ) return a;
        shift128Right( aSig0, 0, 1, &aSig0, &aSig1 );
        expDiff = 0;
    }
    q = ( bSig <= aSig0 );
    if ( q ) aSig0 -= bSig;
    expDiff -= 64;
    while ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig0, aSig1, bSig );
        q = ( 2 < q ) ? q - 2 : 0;
        mul64To128( bSig, q, &term0, &term1 );
        sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
        shortShift128Left( aSig0, aSig1, 62, &aSig0, &aSig1 );
        expDiff -= 62;
    }
    expDiff += 64;
    if ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig0, aSig1, bSig );
        q = ( 2 < q ) ? q - 2 : 0;
        q >>= 64 - expDiff;
        mul64To128( bSig, q<<( 64 - expDiff ), &term0, &term1 );
        sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
        shortShift128Left( 0, bSig, 64 - expDiff, &term0, &term1 );
        while ( le128( term0, term1, aSig0, aSig1 ) ) {
            ++q;
            sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
        }
    }
    else {
        term1 = 0;
        term0 = bSig;
    }
    sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 );
    if (    lt128( alternateASig0, alternateASig1, aSig0, aSig1 )
         || (    eq128( alternateASig0, alternateASig1, aSig0, aSig1 )
              && ( q & 1 ) )
       ) {
        aSig0 = alternateASig0;
        aSig1 = alternateASig1;
        zSign = ! zSign;
    }
    return
        normalizeRoundAndPackFloatx80(
            80, zSign, bExp + expDiff, aSig0, aSig1 );

}

/*----------------------------------------------------------------------------
| Returns the square root of the extended double-precision floating-point
| value `a'.  The operation is performed according to the IEC/IEEE Standard
| for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_sqrt( floatx80 a )
{
    flag aSign;
    int32 aExp, zExp;
    bits64 aSig0, aSig1, zSig0, zSig1, doubleZSig0;
    bits64 rem0, rem1, rem2, rem3, term0, term1, term2, term3;
    floatx80 z;

    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( (bits64) ( aSig0<<1 ) ) return propagateFloatx80NaN( a, a );
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 ) == 0 ) return a;
 invalid:
        float_raise( float_flag_invalid );
        z.low = floatx80_default_nan_low;
        z.high = floatx80_default_nan_high;
        return z;
    }
    if ( aExp == 0 ) {
        if ( aSig0 == 0 ) return packFloatx80( 0, 0, 0 );
        normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 );
    }
    zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFF;
    zSig0 = estimateSqrt32( aExp, aSig0>>32 );
    shift128Right( aSig0, 0, 2 + ( aExp & 1 ), &aSig0, &aSig1 );
    zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0<<32 ) + ( zSig0<<30 );
    doubleZSig0 = zSig0<<1;
    mul64To128( zSig0, zSig0, &term0, &term1 );
    sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 );
    while ( (sbits64) rem0 < 0 ) {
        --zSig0;
        doubleZSig0 -= 2;
        add128( rem0, rem1, zSig0>>63, doubleZSig0 | 1, &rem0, &rem1 );
    }
    zSig1 = estimateDiv128To64( rem1, 0, doubleZSig0 );
    if ( ( zSig1 & LIT64( 0x3FFFFFFFFFFFFFFF ) ) <= 5 ) {
        if ( zSig1 == 0 ) zSig1 = 1;
        mul64To128( doubleZSig0, zSig1, &term1, &term2 );
        sub128( rem1, 0, term1, term2, &rem1, &rem2 );
        mul64To128( zSig1, zSig1, &term2, &term3 );
        sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 );
        while ( (sbits64) rem1 < 0 ) {
            --zSig1;
            shortShift128Left( 0, zSig1, 1, &term2, &term3 );
            term3 |= 1;
            term2 |= doubleZSig0;
            add192( rem1, rem2, rem3, 0, term2, term3, &rem1, &rem2, &rem3 );
        }
        zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 );
    }
    shortShift128Left( 0, zSig1, 1, &zSig0, &zSig1 );
    zSig0 |= doubleZSig0;
    return
        roundAndPackFloatx80(
            floatx80_rounding_precision, 0, zExp, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is
| equal to the corresponding value `b', and 0 otherwise.  The comparison is
| performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_eq( floatx80 a, floatx80 b )
{

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        if (    floatx80_is_signaling_nan( a )
             || floatx80_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
                  && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) )
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is
| less than or equal to the corresponding value `b', and 0 otherwise.  The
| comparison is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_le( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            || (    ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 == 0 );
    }
    return
          aSign ? le128( b.high, b.low, a.high, a.low )
        : le128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is
| less than the corresponding value `b', and 0 otherwise.  The comparison
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_lt( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            && (    ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is equal
| to the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  Otherwise, the comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_eq_signaling( floatx80 a, floatx80 b )
{

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
                  && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) )
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is less
| than or equal to the corresponding value `b', and 0 otherwise.  Quiet NaNs
| do not cause an exception.  Otherwise, the comparison is performed according
| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_le_quiet( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        if (    floatx80_is_signaling_nan( a )
             || floatx80_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            || (    ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 == 0 );
    }
    return
          aSign ? le128( b.high, b.low, a.high, a.low )
        : le128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is less
| than the corresponding value `b', and 0 otherwise.  Quiet NaNs do not cause
| an exception.  Otherwise, the comparison is performed according to the
| IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag floatx80_lt_quiet( floatx80 a, floatx80 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (bits64) ( extractFloatx80Frac( b )<<1 ) )
       ) {
        if (    floatx80_is_signaling_nan( a )
             || floatx80_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            && (    ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

#endif

#ifdef FLOAT128

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the 32-bit two's complement integer format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic---which means in particular that the conversion is rounded
| according to the current rounding mode.  If `a' is a NaN, the largest
| positive integer is returned.  Otherwise, if the conversion overflows, the
| largest integer with the same sign as `a' is returned.
*----------------------------------------------------------------------------*/

int32 float128_to_int32( float128 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig0, aSig1;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) aSign = 0;
    if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 );
    aSig0 |= ( aSig1 != 0 );
    shiftCount = 0x4028 - aExp;
    if ( 0 < shiftCount ) shift64RightJamming( aSig0, shiftCount, &aSig0 );
    return roundAndPackInt32( aSign, aSig0 );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the 32-bit two's complement integer format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic, except that the conversion is always rounded toward zero.  If
| `a' is a NaN, the largest positive integer is returned.  Otherwise, if the
| conversion overflows, the largest integer with the same sign as `a' is
| returned.
*----------------------------------------------------------------------------*/

int32 float128_to_int32_round_to_zero( float128 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig0, aSig1, savedASig;
    int32 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    aSig0 |= ( aSig1 != 0 );
    if ( 0x401E < aExp ) {
        if ( ( aExp == 0x7FFF ) && aSig0 ) aSign = 0;
        goto invalid;
    }
    else if ( aExp < 0x3FFF ) {
        if ( aExp || aSig0 ) float_exception_flags |= float_flag_inexact;
        return 0;
    }
    aSig0 |= LIT64( 0x0001000000000000 );
    shiftCount = 0x402F - aExp;
    savedASig = aSig0;
    aSig0 >>= shiftCount;
    z = aSig0;
    if ( aSign ) z = - z;
    if ( ( z < 0 ) ^ aSign ) {
 invalid:
        float_raise( float_flag_invalid );
        return aSign ? (sbits32) 0x80000000 : 0x7FFFFFFF;
    }
    if ( ( aSig0<<shiftCount ) != savedASig ) {
        float_exception_flags |= float_flag_inexact;
    }
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the 64-bit two's complement integer format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic---which means in particular that the conversion is rounded
| according to the current rounding mode.  If `a' is a NaN, the largest
| positive integer is returned.  Otherwise, if the conversion overflows, the
| largest integer with the same sign as `a' is returned.
*----------------------------------------------------------------------------*/

int64 float128_to_int64( float128 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig0, aSig1;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 );
    shiftCount = 0x402F - aExp;
    if ( shiftCount <= 0 ) {
        if ( 0x403E < aExp ) {
            float_raise( float_flag_invalid );
            if (    ! aSign
                 || (    ( aExp == 0x7FFF )
                      && ( aSig1 || ( aSig0 != LIT64( 0x0001000000000000 ) ) )
                    )
               ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
            return (sbits64) LIT64( 0x8000000000000000 );
        }
        shortShift128Left( aSig0, aSig1, - shiftCount, &aSig0, &aSig1 );
    }
    else {
        shift64ExtraRightJamming( aSig0, aSig1, shiftCount, &aSig0, &aSig1 );
    }
    return roundAndPackInt64( aSign, aSig0, aSig1 );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the 64-bit two's complement integer format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic, except that the conversion is always rounded toward zero.
| If `a' is a NaN, the largest positive integer is returned.  Otherwise, if
| the conversion overflows, the largest integer with the same sign as `a' is
| returned.
*----------------------------------------------------------------------------*/

int64 float128_to_int64_round_to_zero( float128 a )
{
    flag aSign;
    int32 aExp, shiftCount;
    bits64 aSig0, aSig1;
    int64 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp ) aSig0 |= LIT64( 0x0001000000000000 );
    shiftCount = aExp - 0x402F;
    if ( 0 < shiftCount ) {
        if ( 0x403E <= aExp ) {
            aSig0 &= LIT64( 0x0000FFFFFFFFFFFF );
            if (    ( a.high == LIT64( 0xC03E000000000000 ) )
                 && ( aSig1 < LIT64( 0x0002000000000000 ) ) ) {
                if ( aSig1 ) float_exception_flags |= float_flag_inexact;
            }
            else {
                float_raise( float_flag_invalid );
                if ( ! aSign || ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) ) {
                    return LIT64( 0x7FFFFFFFFFFFFFFF );
                }
            }
            return (sbits64) LIT64( 0x8000000000000000 );
        }
        z = ( aSig0<<shiftCount ) | ( aSig1>>( ( - shiftCount ) & 63 ) );
        if ( (bits64) ( aSig1<<shiftCount ) ) {
            float_exception_flags |= float_flag_inexact;
        }
    }
    else {
        if ( aExp < 0x3FFF ) {
            if ( aExp | aSig0 | aSig1 ) {
                float_exception_flags |= float_flag_inexact;
            }
            return 0;
        }
        z = aSig0>>( - shiftCount );
        if (    aSig1
             || ( shiftCount && (bits64) ( aSig0<<( shiftCount & 63 ) ) ) ) {
            float_exception_flags |= float_flag_inexact;
        }
    }
    if ( aSign ) z = - z;
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the single-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

float32 float128_to_float32( float128 a )
{
    flag aSign;
    int32 aExp;
    bits64 aSig0, aSig1;
    bits32 zSig;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
            return commonNaNToFloat32( float128ToCommonNaN( a ) );
        }
        return packFloat32( aSign, 0xFF, 0 );
    }
    aSig0 |= ( aSig1 != 0 );
    shift64RightJamming( aSig0, 18, &aSig0 );
    zSig = aSig0;
    if ( aExp || zSig ) {
        zSig |= 0x40000000;
        aExp -= 0x3F81;
    }
    return roundAndPackFloat32( aSign, aExp, zSig );

}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the double-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

float64 float128_to_float64( float128 a )
{
    flag aSign;
    int32 aExp;
    bits64 aSig0, aSig1;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
            return commonNaNToFloat64( float128ToCommonNaN( a ) );
        }
        return packFloat64( aSign, 0x7FF, 0 );
    }
    shortShift128Left( aSig0, aSig1, 14, &aSig0, &aSig1 );
    aSig0 |= ( aSig1 != 0 );
    if ( aExp || aSig0 ) {
        aSig0 |= LIT64( 0x4000000000000000 );
        aExp -= 0x3C01;
    }
    return roundAndPackFloat64( aSign, aExp, aSig0 );

}

#ifdef FLOATX80

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
| value `a' to the extended double-precision floating-point format.  The
| conversion is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 float128_to_floatx80( float128 a )
{
    flag aSign;
    int32 aExp;
    bits64 aSig0, aSig1;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
            return commonNaNToFloatx80( float128ToCommonNaN( a ) );
        }
        return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
    }
    if ( aExp == 0 ) {
        if ( ( aSig0 | aSig1 ) == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 );
    }
    else {
        aSig0 |= LIT64( 0x0001000000000000 );
    }
    shortShift128Left( aSig0, aSig1, 15, &aSig0, &aSig1 );
    return roundAndPackFloatx80( 80, aSign, aExp, aSig0, aSig1 );

}

#endif

/*----------------------------------------------------------------------------
| Rounds the quadruple-precision floating-point value `a' to an integer, and
| returns the result as a quadruple-precision floating-point value.  The
| operation is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_round_to_int( float128 a )
{
    flag aSign;
    int32 aExp;
    bits64 lastBitMask, roundBitsMask;
    int8 roundingMode;
    float128 z;

    aExp = extractFloat128Exp( a );
    if ( 0x402F <= aExp ) {
        if ( 0x406F <= aExp ) {
            if (    ( aExp == 0x7FFF )
                 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) )
               ) {
                return propagateFloat128NaN( a, a );
            }
            return a;
        }
        lastBitMask = 1;
        lastBitMask = ( lastBitMask<<( 0x406E - aExp ) )<<1;
        roundBitsMask = lastBitMask - 1;
        z = a;
        roundingMode = float_rounding_mode;
        if ( roundingMode == float_round_nearest_even ) {
            if ( lastBitMask ) {
                add128( z.high, z.low, 0, lastBitMask>>1, &z.high, &z.low );
                if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask;
            }
            else {
                if ( (sbits64) z.low < 0 ) {
                    ++z.high;
                    if ( (bits64) ( z.low<<1 ) == 0 ) z.high &= ~1;
                }
            }
        }
        else if ( roundingMode != float_round_to_zero ) {
            if (   extractFloat128Sign( z )
                 ^ ( roundingMode == float_round_up ) ) {
                add128( z.high, z.low, 0, roundBitsMask, &z.high, &z.low );
            }
        }
        z.low &= ~ roundBitsMask;
    }
    else {
        if ( aExp < 0x3FFF ) {
            if ( ( ( (bits64) ( a.high<<1 ) ) | a.low ) == 0 ) return a;
            float_exception_flags |= float_flag_inexact;
            aSign = extractFloat128Sign( a );
            switch ( float_rounding_mode ) {
             case float_round_nearest_even:
                if (    ( aExp == 0x3FFE )
                     && (   extractFloat128Frac0( a )
                          | extractFloat128Frac1( a ) )
                   ) {
                    return packFloat128( aSign, 0x3FFF, 0, 0 );
                }
                break;
             case float_round_down:
                return
                      aSign ? packFloat128( 1, 0x3FFF, 0, 0 )
                    : packFloat128( 0, 0, 0, 0 );
             case float_round_up:
                return
                      aSign ? packFloat128( 1, 0, 0, 0 )
                    : packFloat128( 0, 0x3FFF, 0, 0 );
            }
            return packFloat128( aSign, 0, 0, 0 );
        }
        lastBitMask = 1;
        lastBitMask <<= 0x402F - aExp;
        roundBitsMask = lastBitMask - 1;
        z.low = 0;
        z.high = a.high;
        roundingMode = float_rounding_mode;
        if ( roundingMode == float_round_nearest_even ) {
            z.high += lastBitMask>>1;
            if ( ( ( z.high & roundBitsMask ) | a.low ) == 0 ) {
                z.high &= ~ lastBitMask;
            }
        }
        else if ( roundingMode != float_round_to_zero ) {
            if (   extractFloat128Sign( z )
                 ^ ( roundingMode == float_round_up ) ) {
                z.high |= ( a.low != 0 );
                z.high += roundBitsMask;
            }
        }
        z.high &= ~ roundBitsMask;
    }
    if ( ( z.low != a.low ) || ( z.high != a.high ) ) {
        float_exception_flags |= float_flag_inexact;
    }
    return z;

}

/*----------------------------------------------------------------------------
| Returns the result of adding the absolute values of the quadruple-precision
| floating-point values `a' and `b'.  If `zSign' is 1, the sum is negated
| before being returned.  `zSign' is ignored if the result is a NaN.
| The addition is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static float128 addFloat128Sigs( float128 a, float128 b, flag zSign )
{
    int32 aExp, bExp, zExp;
    bits64 aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
    int32 expDiff;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    expDiff = aExp - bExp;
    if ( 0 < expDiff ) {
        if ( aExp == 0x7FFF ) {
            if ( aSig0 | aSig1 ) return propagateFloat128NaN( a, b );
            return a;
        }
        if ( bExp == 0 ) {
            --expDiff;
        }
        else {
            bSig0 |= LIT64( 0x0001000000000000 );
        }
        shift128ExtraRightJamming(
            bSig0, bSig1, 0, expDiff, &bSig0, &bSig1, &zSig2 );
        zExp = aExp;
    }
    else if ( expDiff < 0 ) {
        if ( bExp == 0x7FFF ) {
            if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
            return packFloat128( zSign, 0x7FFF, 0, 0 );
        }
        if ( aExp == 0 ) {
            ++expDiff;
        }
        else {
            aSig0 |= LIT64( 0x0001000000000000 );
        }
        shift128ExtraRightJamming(
            aSig0, aSig1, 0, - expDiff, &aSig0, &aSig1, &zSig2 );
        zExp = bExp;
    }
    else {
        if ( aExp == 0x7FFF ) {
            if ( aSig0 | aSig1 | bSig0 | bSig1 ) {
                return propagateFloat128NaN( a, b );
            }
            return a;
        }
        add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
        if ( aExp == 0 ) return packFloat128( zSign, 0, zSig0, zSig1 );
        zSig2 = 0;
        zSig0 |= LIT64( 0x0002000000000000 );
        zExp = aExp;
        goto shiftRight1;
    }
    aSig0 |= LIT64( 0x0001000000000000 );
    add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
    --zExp;
    if ( zSig0 < LIT64( 0x0002000000000000 ) ) goto roundAndPack;
    ++zExp;
 shiftRight1:
    shift128ExtraRightJamming(
        zSig0, zSig1, zSig2, 1, &zSig0, &zSig1, &zSig2 );
 roundAndPack:
    return roundAndPackFloat128( zSign, zExp, zSig0, zSig1, zSig2 );

}

/*----------------------------------------------------------------------------
| Returns the result of subtracting the absolute values of the quadruple-
| precision floating-point values `a' and `b'.  If `zSign' is 1, the
| difference is negated before being returned.  `zSign' is ignored if the
| result is a NaN.  The subtraction is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

static float128 subFloat128Sigs( float128 a, float128 b, flag zSign )
{
    int32 aExp, bExp, zExp;
    bits64 aSig0, aSig1, bSig0, bSig1, zSig0, zSig1;
    int32 expDiff;
    float128 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    expDiff = aExp - bExp;
    shortShift128Left( aSig0, aSig1, 14, &aSig0, &aSig1 );
    shortShift128Left( bSig0, bSig1, 14, &bSig0, &bSig1 );
    if ( 0 < expDiff ) goto aExpBigger;
    if ( expDiff < 0 ) goto bExpBigger;
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 | bSig0 | bSig1 ) {
            return propagateFloat128NaN( a, b );
        }
        float_raise( float_flag_invalid );
        z.low = float128_default_nan_low;
        z.high = float128_default_nan_high;
        return z;
    }
    if ( aExp == 0 ) {
        aExp = 1;
        bExp = 1;
    }
    if ( bSig0 < aSig0 ) goto aBigger;
    if ( aSig0 < bSig0 ) goto bBigger;
    if ( bSig1 < aSig1 ) goto aBigger;
    if ( aSig1 < bSig1 ) goto bBigger;
    return packFloat128( float_rounding_mode == float_round_down, 0, 0, 0 );
 bExpBigger:
    if ( bExp == 0x7FFF ) {
        if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
        return packFloat128( zSign ^ 1, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        ++expDiff;
    }
    else {
        aSig0 |= LIT64( 0x4000000000000000 );
    }
    shift128RightJamming( aSig0, aSig1, - expDiff, &aSig0, &aSig1 );
    bSig0 |= LIT64( 0x4000000000000000 );
 bBigger:
    sub128( bSig0, bSig1, aSig0, aSig1, &zSig0, &zSig1 );
    zExp = bExp;
    zSign ^= 1;
    goto normalizeRoundAndPack;
 aExpBigger:
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) return propagateFloat128NaN( a, b );
        return a;
    }
    if ( bExp == 0 ) {
        --expDiff;
    }
    else {
        bSig0 |= LIT64( 0x4000000000000000 );
    }
    shift128RightJamming( bSig0, bSig1, expDiff, &bSig0, &bSig1 );
    aSig0 |= LIT64( 0x4000000000000000 );
 aBigger:
    sub128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
    zExp = aExp;
 normalizeRoundAndPack:
    --zExp;
    return normalizeRoundAndPackFloat128( zSign, zExp - 14, zSig0, zSig1 );

}

/*----------------------------------------------------------------------------
| Returns the result of adding the quadruple-precision floating-point values
| `a' and `b'.  The operation is performed according to the IEC/IEEE Standard
| for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_add( float128 a, float128 b )
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
        return addFloat128Sigs( a, b, aSign );
    }
    else {
        return subFloat128Sigs( a, b, aSign );
    }

}

/*----------------------------------------------------------------------------
| Returns the result of subtracting the quadruple-precision floating-point
| values `a' and `b'.  The operation is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_sub( float128 a, float128 b )
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
        return subFloat128Sigs( a, b, aSign );
    }
    else {
        return addFloat128Sigs( a, b, aSign );
    }

}

/*----------------------------------------------------------------------------
| Returns the result of multiplying the quadruple-precision floating-point
| values `a' and `b'.  The operation is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_mul( float128 a, float128 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, zExp;
    bits64 aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2, zSig3;
    float128 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    bSign = extractFloat128Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
        if (    ( aSig0 | aSig1 )
             || ( ( bExp == 0x7FFF ) && ( bSig0 | bSig1 ) ) ) {
            return propagateFloat128NaN( a, b );
        }
        if ( ( bExp | bSig0 | bSig1 ) == 0 ) goto invalid;
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
        if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) {
 invalid:
            float_raise( float_flag_invalid );
            z.low = float128_default_nan_low;
            z.high = float128_default_nan_high;
            return z;
        }
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 );
        normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 );
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 );
        normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 );
    }
    zExp = aExp + bExp - 0x4000;
    aSig0 |= LIT64( 0x0001000000000000 );
    shortShift128Left( bSig0, bSig1, 16, &bSig0, &bSig1 );
    mul128To256( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1, &zSig2, &zSig3 );
    add128( zSig0, zSig1, aSig0, aSig1, &zSig0, &zSig1 );
    zSig2 |= ( zSig3 != 0 );
    if ( LIT64( 0x0002000000000000 ) <= zSig0 ) {
        shift128ExtraRightJamming(
            zSig0, zSig1, zSig2, 1, &zSig0, &zSig1, &zSig2 );
        ++zExp;
    }
    return roundAndPackFloat128( zSign, zExp, zSig0, zSig1, zSig2 );

}

/*----------------------------------------------------------------------------
| Returns the result of dividing the quadruple-precision floating-point value
| `a' by the corresponding value `b'.  The operation is performed according to
| the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_div( float128 a, float128 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, zExp;
    bits64 aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
    bits64 rem0, rem1, rem2, rem3, term0, term1, term2, term3;
    float128 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    bSign = extractFloat128Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) return propagateFloat128NaN( a, b );
        if ( bExp == 0x7FFF ) {
            if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
            goto invalid;
        }
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
        if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
        return packFloat128( zSign, 0, 0, 0 );
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) {
            if ( ( aExp | aSig0 | aSig1 ) == 0 ) {
 invalid:
                float_raise( float_flag_invalid );
                z.low = float128_default_nan_low;
                z.high = float128_default_nan_high;
                return z;
            }
            float_raise( float_flag_divbyzero );
            return packFloat128( zSign, 0x7FFF, 0, 0 );
        }
        normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 );
    }
    if ( aExp == 0 ) {
        if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( zSign, 0, 0, 0 );
        normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 );
    }
    zExp = aExp - bExp + 0x3FFD;
    shortShift128Left(
        aSig0 | LIT64( 0x0001000000000000 ), aSig1, 15, &aSig0, &aSig1 );
    shortShift128Left(
        bSig0 | LIT64( 0x0001000000000000 ), bSig1, 15, &bSig0, &bSig1 );
    if ( le128( bSig0, bSig1, aSig0, aSig1 ) ) {
        shift128Right( aSig0, aSig1, 1, &aSig0, &aSig1 );
        ++zExp;
    }
    zSig0 = estimateDiv128To64( aSig0, aSig1, bSig0 );
    mul128By64To192( bSig0, bSig1, zSig0, &term0, &term1, &term2 );
    sub192( aSig0, aSig1, 0, term0, term1, term2, &rem0, &rem1, &rem2 );
    while ( (sbits64) rem0 < 0 ) {
        --zSig0;
        add192( rem0, rem1, rem2, 0, bSig0, bSig1, &rem0, &rem1, &rem2 );
    }
    zSig1 = estimateDiv128To64( rem1, rem2, bSig0 );
    if ( ( zSig1 & 0x3FFF ) <= 4 ) {
        mul128By64To192( bSig0, bSig1, zSig1, &term1, &term2, &term3 );
        sub192( rem1, rem2, 0, term1, term2, term3, &rem1, &rem2, &rem3 );
        while ( (sbits64) rem1 < 0 ) {
            --zSig1;
            add192( rem1, rem2, rem3, 0, bSig0, bSig1, &rem1, &rem2, &rem3 );
        }
        zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 );
    }
    shift128ExtraRightJamming( zSig0, zSig1, 0, 15, &zSig0, &zSig1, &zSig2 );
    return roundAndPackFloat128( zSign, zExp, zSig0, zSig1, zSig2 );

}

/*----------------------------------------------------------------------------
| Returns the remainder of the quadruple-precision floating-point value `a'
| with respect to the corresponding value `b'.  The operation is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_rem( float128 a, float128 b )
{
    flag aSign, bSign, zSign;
    int32 aExp, bExp, expDiff;
    bits64 aSig0, aSig1, bSig0, bSig1, q, term0, term1, term2;
    bits64 allZero, alternateASig0, alternateASig1, sigMean1;
    sbits64 sigMean0;
    float128 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    bSign = extractFloat128Sign( b );
    if ( aExp == 0x7FFF ) {
        if (    ( aSig0 | aSig1 )
             || ( ( bExp == 0x7FFF ) && ( bSig0 | bSig1 ) ) ) {
            return propagateFloat128NaN( a, b );
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
        if ( bSig0 | bSig1 ) return propagateFloat128NaN( a, b );
        return a;
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) {
 invalid:
            float_raise( float_flag_invalid );
            z.low = float128_default_nan_low;
            z.high = float128_default_nan_high;
            return z;
        }
        normalizeFloat128Subnormal( bSig0, bSig1, &bExp, &bSig0, &bSig1 );
    }
    if ( aExp == 0 ) {
        if ( ( aSig0 | aSig1 ) == 0 ) return a;
        normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 );
    }
    expDiff = aExp - bExp;
    if ( expDiff < -1 ) return a;
    shortShift128Left(
        aSig0 | LIT64( 0x0001000000000000 ),
        aSig1,
        15 - ( expDiff < 0 ),
        &aSig0,
        &aSig1
    );
    shortShift128Left(
        bSig0 | LIT64( 0x0001000000000000 ), bSig1, 15, &bSig0, &bSig1 );
    q = le128( bSig0, bSig1, aSig0, aSig1 );
    if ( q ) sub128( aSig0, aSig1, bSig0, bSig1, &aSig0, &aSig1 );
    expDiff -= 64;
    while ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig0, aSig1, bSig0 );
        q = ( 4 < q ) ? q - 4 : 0;
        mul128By64To192( bSig0, bSig1, q, &term0, &term1, &term2 );
        shortShift192Left( term0, term1, term2, 61, &term1, &term2, &allZero );
        shortShift128Left( aSig0, aSig1, 61, &aSig0, &allZero );
        sub128( aSig0, 0, term1, term2, &aSig0, &aSig1 );
        expDiff -= 61;
    }
    if ( -64 < expDiff ) {
        q = estimateDiv128To64( aSig0, aSig1, bSig0 );
        q = ( 4 < q ) ? q - 4 : 0;
        q >>= - expDiff;
        shift128Right( bSig0, bSig1, 12, &bSig0, &bSig1 );
        expDiff += 52;
        if ( expDiff < 0 ) {
            shift128Right( aSig0, aSig1, - expDiff, &aSig0, &aSig1 );
        }
        else {
            shortShift128Left( aSig0, aSig1, expDiff, &aSig0, &aSig1 );
        }
        mul128By64To192( bSig0, bSig1, q, &term0, &term1, &term2 );
        sub128( aSig0, aSig1, term1, term2, &aSig0, &aSig1 );
    }
    else {
        shift128Right( aSig0, aSig1, 12, &aSig0, &aSig1 );
        shift128Right( bSig0, bSig1, 12, &bSig0, &bSig1 );
    }
    do {
        alternateASig0 = aSig0;
        alternateASig1 = aSig1;
        ++q;
        sub128( aSig0, aSig1, bSig0, bSig1, &aSig0, &aSig1 );
    } while ( 0 <= (sbits64) aSig0 );
    add128(
        aSig0, aSig1, alternateASig0, alternateASig1, &sigMean0, &sigMean1 );
    if (    ( sigMean0 < 0 )
         || ( ( ( sigMean0 | sigMean1 ) == 0 ) && ( q & 1 ) ) ) {
        aSig0 = alternateASig0;
        aSig1 = alternateASig1;
    }
    zSign = ( (sbits64) aSig0 < 0 );
    if ( zSign ) sub128( 0, 0, aSig0, aSig1, &aSig0, &aSig1 );
    return
        normalizeRoundAndPackFloat128( aSign ^ zSign, bExp - 4, aSig0, aSig1 );

}

/*----------------------------------------------------------------------------
| Returns the square root of the quadruple-precision floating-point value `a'.
| The operation is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

float128 float128_sqrt( float128 a )
{
    flag aSign;
    int32 aExp, zExp;
    bits64 aSig0, aSig1, zSig0, zSig1, zSig2, doubleZSig0;
    bits64 rem0, rem1, rem2, rem3, term0, term1, term2, term3;
    float128 z;

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) return propagateFloat128NaN( a, a );
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) return a;
 invalid:
        float_raise( float_flag_invalid );
        z.low = float128_default_nan_low;
        z.high = float128_default_nan_high;
        return z;
    }
    if ( aExp == 0 ) {
        if ( ( aSig0 | aSig1 ) == 0 ) return packFloat128( 0, 0, 0, 0 );
        normalizeFloat128Subnormal( aSig0, aSig1, &aExp, &aSig0, &aSig1 );
    }
    zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFE;
    aSig0 |= LIT64( 0x0001000000000000 );
    zSig0 = estimateSqrt32( aExp, aSig0>>17 );
    shortShift128Left( aSig0, aSig1, 13 - ( aExp & 1 ), &aSig0, &aSig1 );
    zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0<<32 ) + ( zSig0<<30 );
    doubleZSig0 = zSig0<<1;
    mul64To128( zSig0, zSig0, &term0, &term1 );
    sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 );
    while ( (sbits64) rem0 < 0 ) {
        --zSig0;
        doubleZSig0 -= 2;
        add128( rem0, rem1, zSig0>>63, doubleZSig0 | 1, &rem0, &rem1 );
    }
    zSig1 = estimateDiv128To64( rem1, 0, doubleZSig0 );
    if ( ( zSig1 & 0x1FFF ) <= 5 ) {
        if ( zSig1 == 0 ) zSig1 = 1;
        mul64To128( doubleZSig0, zSig1, &term1, &term2 );
        sub128( rem1, 0, term1, term2, &rem1, &rem2 );
        mul64To128( zSig1, zSig1, &term2, &term3 );
        sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 );
        while ( (sbits64) rem1 < 0 ) {
            --zSig1;
            shortShift128Left( 0, zSig1, 1, &term2, &term3 );
            term3 |= 1;
            term2 |= doubleZSig0;
            add192( rem1, rem2, rem3, 0, term2, term3, &rem1, &rem2, &rem3 );
        }
        zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 );
    }
    shift128ExtraRightJamming( zSig0, zSig1, 0, 14, &zSig0, &zSig1, &zSig2 );
    return roundAndPackFloat128( 0, zExp, zSig0, zSig1, zSig2 );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
| the corresponding value `b', and 0 otherwise.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_eq( float128 a, float128 b )
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        if (    float128_is_signaling_nan( a )
             || float128_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
                  && ( (bits64) ( ( a.high | b.high )<<1 ) == 0 ) )
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
| or equal to the corresponding value `b', and 0 otherwise.  The comparison
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_le( float128 a, float128 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            || (    ( ( (bits64) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 == 0 );
    }
    return
          aSign ? le128( b.high, b.low, a.high, a.low )
        : le128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
| the corresponding value `b', and 0 otherwise.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_lt( float128 a, float128 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            && (    ( ( (bits64) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  Otherwise, the comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_eq_signaling( float128 a, float128 b )
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        float_raise( float_flag_invalid );
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
                  && ( (bits64) ( ( a.high | b.high )<<1 ) == 0 ) )
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
| or equal to the corresponding value `b', and 0 otherwise.  Quiet NaNs do not
| cause an exception.  Otherwise, the comparison is performed according to the
| IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_le_quiet( float128 a, float128 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        if (    float128_is_signaling_nan( a )
             || float128_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            || (    ( ( (bits64) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 == 0 );
    }
    return
          aSign ? le128( b.high, b.low, a.high, a.low )
        : le128( a.high, a.low, b.high, b.low );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
| the corresponding value `b', and 0 otherwise.  Quiet NaNs do not cause an
| exception.  Otherwise, the comparison is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

flag float128_lt_quiet( float128 a, float128 b )
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
        if (    float128_is_signaling_nan( a )
             || float128_is_signaling_nan( b ) ) {
            float_raise( float_flag_invalid );
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
            && (    ( ( (bits64) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

#endif