softfloat.c 243.9 KB
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/*
 * QEMU float support
 *
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 * The code in this source file is derived from release 2a of the SoftFloat
 * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and
 * some later contributions) are provided under that license, as detailed below.
 * It has subsequently been modified by contributors to the QEMU Project,
 * so some portions are provided under:
 *  the SoftFloat-2a license
 *  the BSD license
 *  GPL-v2-or-later
 *
 * Any future contributions to this file after December 1st 2014 will be
 * taken to be licensed under the Softfloat-2a license unless specifically
 * indicated otherwise.
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 */
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/*
===============================================================================
This C source file is part of the SoftFloat IEC/IEEE Floating-point
Arithmetic Package, Release 2a.
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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
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is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
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arithmetic/SoftFloat.html'.

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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 ANY
AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
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Derivative works are acceptable, even for commercial purposes, so long as
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(1) they include prominent notice that the work is derivative, and (2) they
include prominent notice akin to these four paragraphs for those parts of
this code that are retained.
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===============================================================================
*/
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/* BSD licensing:
 * Copyright (c) 2006, Fabrice Bellard
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

/* Portions of this work are licensed under the terms of the GNU GPL,
 * version 2 or later. See the COPYING file in the top-level directory.
 */

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/* softfloat (and in particular the code in softfloat-specialize.h) is
 * target-dependent and needs the TARGET_* macros.
 */
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#include "qemu/osdep.h"
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#include "qemu/bitops.h"
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#include "fpu/softfloat.h"
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/* We only need stdlib for abort() */

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/*----------------------------------------------------------------------------
| Primitive arithmetic functions, including multi-word arithmetic, and
| division and square root approximations.  (Can be specialized to target if
| desired.)
*----------------------------------------------------------------------------*/
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#include "fpu/softfloat-macros.h"
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/*----------------------------------------------------------------------------
| Returns the fraction bits of the half-precision floating-point value `a'.
*----------------------------------------------------------------------------*/

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static inline uint32_t extractFloat16Frac(float16 a)
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{
    return float16_val(a) & 0x3ff;
}

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

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static inline int extractFloat16Exp(float16 a)
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{
    return (float16_val(a) >> 10) & 0x1f;
}

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

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static inline flag extractFloat16Sign(float16 a)
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{
    return float16_val(a)>>15;
}

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

static inline uint32_t extractFloat32Frac(float32 a)
{
    return float32_val(a) & 0x007FFFFF;
}

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

static inline int extractFloat32Exp(float32 a)
{
    return (float32_val(a) >> 23) & 0xFF;
}

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

static inline flag extractFloat32Sign(float32 a)
{
    return float32_val(a) >> 31;
}

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

static inline uint64_t extractFloat64Frac(float64 a)
{
    return float64_val(a) & LIT64(0x000FFFFFFFFFFFFF);
}

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

static inline int extractFloat64Exp(float64 a)
{
    return (float64_val(a) >> 52) & 0x7FF;
}

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

static inline flag extractFloat64Sign(float64 a)
{
    return float64_val(a) >> 63;
}

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/*
 * Classify a floating point number. Everything above float_class_qnan
 * is a NaN so cls >= float_class_qnan is any NaN.
 */

typedef enum __attribute__ ((__packed__)) {
    float_class_unclassified,
    float_class_zero,
    float_class_normal,
    float_class_inf,
    float_class_qnan,  /* all NaNs from here */
    float_class_snan,
    float_class_msnan, /* maybe silenced */
} FloatClass;

/*
 * Structure holding all of the decomposed parts of a float. The
 * exponent is unbiased and the fraction is normalized. All
 * calculations are done with a 64 bit fraction and then rounded as
 * appropriate for the final format.
 *
 * Thanks to the packed FloatClass a decent compiler should be able to
 * fit the whole structure into registers and avoid using the stack
 * for parameter passing.
 */

typedef struct {
    uint64_t frac;
    int32_t  exp;
    FloatClass cls;
    bool sign;
} FloatParts;

#define DECOMPOSED_BINARY_POINT    (64 - 2)
#define DECOMPOSED_IMPLICIT_BIT    (1ull << DECOMPOSED_BINARY_POINT)
#define DECOMPOSED_OVERFLOW_BIT    (DECOMPOSED_IMPLICIT_BIT << 1)

/* Structure holding all of the relevant parameters for a format.
 *   exp_size: the size of the exponent field
 *   exp_bias: the offset applied to the exponent field
 *   exp_max: the maximum normalised exponent
 *   frac_size: the size of the fraction field
 *   frac_shift: shift to normalise the fraction with DECOMPOSED_BINARY_POINT
 * The following are computed based the size of fraction
 *   frac_lsb: least significant bit of fraction
 *   fram_lsbm1: the bit bellow the least significant bit (for rounding)
 *   round_mask/roundeven_mask: masks used for rounding
 */
typedef struct {
    int exp_size;
    int exp_bias;
    int exp_max;
    int frac_size;
    int frac_shift;
    uint64_t frac_lsb;
    uint64_t frac_lsbm1;
    uint64_t round_mask;
    uint64_t roundeven_mask;
} FloatFmt;

/* Expand fields based on the size of exponent and fraction */
#define FLOAT_PARAMS(E, F)                                           \
    .exp_size       = E,                                             \
    .exp_bias       = ((1 << E) - 1) >> 1,                           \
    .exp_max        = (1 << E) - 1,                                  \
    .frac_size      = F,                                             \
    .frac_shift     = DECOMPOSED_BINARY_POINT - F,                   \
    .frac_lsb       = 1ull << (DECOMPOSED_BINARY_POINT - F),         \
    .frac_lsbm1     = 1ull << ((DECOMPOSED_BINARY_POINT - F) - 1),   \
    .round_mask     = (1ull << (DECOMPOSED_BINARY_POINT - F)) - 1,   \
    .roundeven_mask = (2ull << (DECOMPOSED_BINARY_POINT - F)) - 1

static const FloatFmt float16_params = {
    FLOAT_PARAMS(5, 10)
};

static const FloatFmt float32_params = {
    FLOAT_PARAMS(8, 23)
};

static const FloatFmt float64_params = {
    FLOAT_PARAMS(11, 52)
};

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/* Unpack a float to parts, but do not canonicalize.  */
static inline FloatParts unpack_raw(FloatFmt fmt, uint64_t raw)
{
    const int sign_pos = fmt.frac_size + fmt.exp_size;

    return (FloatParts) {
        .cls = float_class_unclassified,
        .sign = extract64(raw, sign_pos, 1),
        .exp = extract64(raw, fmt.frac_size, fmt.exp_size),
        .frac = extract64(raw, 0, fmt.frac_size),
    };
}

static inline FloatParts float16_unpack_raw(float16 f)
{
    return unpack_raw(float16_params, f);
}

static inline FloatParts float32_unpack_raw(float32 f)
{
    return unpack_raw(float32_params, f);
}

static inline FloatParts float64_unpack_raw(float64 f)
{
    return unpack_raw(float64_params, f);
}

/* Pack a float from parts, but do not canonicalize.  */
static inline uint64_t pack_raw(FloatFmt fmt, FloatParts p)
{
    const int sign_pos = fmt.frac_size + fmt.exp_size;
    uint64_t ret = deposit64(p.frac, fmt.frac_size, fmt.exp_size, p.exp);
    return deposit64(ret, sign_pos, 1, p.sign);
}

static inline float16 float16_pack_raw(FloatParts p)
{
    return make_float16(pack_raw(float16_params, p));
}

static inline float32 float32_pack_raw(FloatParts p)
{
    return make_float32(pack_raw(float32_params, p));
}

static inline float64 float64_pack_raw(FloatParts p)
{
    return make_float64(pack_raw(float64_params, p));
}

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/*----------------------------------------------------------------------------
| 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.h"

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/* Canonicalize EXP and FRAC, setting CLS.  */
static FloatParts canonicalize(FloatParts part, const FloatFmt *parm,
                               float_status *status)
{
    if (part.exp == parm->exp_max) {
        if (part.frac == 0) {
            part.cls = float_class_inf;
        } else {
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            part.frac <<= parm->frac_shift;
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            part.cls = (parts_is_snan_frac(part.frac, status)
                        ? float_class_snan : float_class_qnan);
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        }
    } else if (part.exp == 0) {
        if (likely(part.frac == 0)) {
            part.cls = float_class_zero;
        } else if (status->flush_inputs_to_zero) {
            float_raise(float_flag_input_denormal, status);
            part.cls = float_class_zero;
            part.frac = 0;
        } else {
            int shift = clz64(part.frac) - 1;
            part.cls = float_class_normal;
            part.exp = parm->frac_shift - parm->exp_bias - shift + 1;
            part.frac <<= shift;
        }
    } else {
        part.cls = float_class_normal;
        part.exp -= parm->exp_bias;
        part.frac = DECOMPOSED_IMPLICIT_BIT + (part.frac << parm->frac_shift);
    }
    return part;
}

/* Round and uncanonicalize a floating-point number by parts. There
 * are FRAC_SHIFT bits that may require rounding at the bottom of the
 * fraction; these bits will be removed. The exponent will be biased
 * by EXP_BIAS and must be bounded by [EXP_MAX-1, 0].
 */

static FloatParts round_canonical(FloatParts p, float_status *s,
                                  const FloatFmt *parm)
{
    const uint64_t frac_lsbm1 = parm->frac_lsbm1;
    const uint64_t round_mask = parm->round_mask;
    const uint64_t roundeven_mask = parm->roundeven_mask;
    const int exp_max = parm->exp_max;
    const int frac_shift = parm->frac_shift;
    uint64_t frac, inc;
    int exp, flags = 0;
    bool overflow_norm;

    frac = p.frac;
    exp = p.exp;

    switch (p.cls) {
    case float_class_normal:
        switch (s->float_rounding_mode) {
        case float_round_nearest_even:
            overflow_norm = false;
            inc = ((frac & roundeven_mask) != frac_lsbm1 ? frac_lsbm1 : 0);
            break;
        case float_round_ties_away:
            overflow_norm = false;
            inc = frac_lsbm1;
            break;
        case float_round_to_zero:
            overflow_norm = true;
            inc = 0;
            break;
        case float_round_up:
            inc = p.sign ? 0 : round_mask;
            overflow_norm = p.sign;
            break;
        case float_round_down:
            inc = p.sign ? round_mask : 0;
            overflow_norm = !p.sign;
            break;
        default:
            g_assert_not_reached();
        }

        exp += parm->exp_bias;
        if (likely(exp > 0)) {
            if (frac & round_mask) {
                flags |= float_flag_inexact;
                frac += inc;
                if (frac & DECOMPOSED_OVERFLOW_BIT) {
                    frac >>= 1;
                    exp++;
                }
            }
            frac >>= frac_shift;

            if (unlikely(exp >= exp_max)) {
                flags |= float_flag_overflow | float_flag_inexact;
                if (overflow_norm) {
                    exp = exp_max - 1;
                    frac = -1;
                } else {
                    p.cls = float_class_inf;
                    goto do_inf;
                }
            }
        } else if (s->flush_to_zero) {
            flags |= float_flag_output_denormal;
            p.cls = float_class_zero;
            goto do_zero;
        } else {
            bool is_tiny = (s->float_detect_tininess
                            == float_tininess_before_rounding)
                        || (exp < 0)
                        || !((frac + inc) & DECOMPOSED_OVERFLOW_BIT);

            shift64RightJamming(frac, 1 - exp, &frac);
            if (frac & round_mask) {
                /* Need to recompute round-to-even.  */
                if (s->float_rounding_mode == float_round_nearest_even) {
                    inc = ((frac & roundeven_mask) != frac_lsbm1
                           ? frac_lsbm1 : 0);
                }
                flags |= float_flag_inexact;
                frac += inc;
            }

            exp = (frac & DECOMPOSED_IMPLICIT_BIT ? 1 : 0);
            frac >>= frac_shift;

            if (is_tiny && (flags & float_flag_inexact)) {
                flags |= float_flag_underflow;
            }
            if (exp == 0 && frac == 0) {
                p.cls = float_class_zero;
            }
        }
        break;

    case float_class_zero:
    do_zero:
        exp = 0;
        frac = 0;
        break;

    case float_class_inf:
    do_inf:
        exp = exp_max;
        frac = 0;
        break;

    case float_class_qnan:
    case float_class_snan:
        exp = exp_max;
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        frac >>= parm->frac_shift;
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        break;

    default:
        g_assert_not_reached();
    }

    float_raise(flags, s);
    p.exp = exp;
    p.frac = frac;
    return p;
}

static FloatParts float16_unpack_canonical(float16 f, float_status *s)
{
    return canonicalize(float16_unpack_raw(f), &float16_params, s);
}

static float16 float16_round_pack_canonical(FloatParts p, float_status *s)
{
    switch (p.cls) {
    case float_class_msnan:
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        p.frac >>= float16_params.frac_shift;
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        return float16_maybe_silence_nan(float16_pack_raw(p), s);
    default:
        p = round_canonical(p, s, &float16_params);
        return float16_pack_raw(p);
    }
}

static FloatParts float32_unpack_canonical(float32 f, float_status *s)
{
    return canonicalize(float32_unpack_raw(f), &float32_params, s);
}

static float32 float32_round_pack_canonical(FloatParts p, float_status *s)
{
    switch (p.cls) {
    case float_class_msnan:
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        p.frac >>= float32_params.frac_shift;
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        return float32_maybe_silence_nan(float32_pack_raw(p), s);
    default:
        p = round_canonical(p, s, &float32_params);
        return float32_pack_raw(p);
    }
}

static FloatParts float64_unpack_canonical(float64 f, float_status *s)
{
    return canonicalize(float64_unpack_raw(f), &float64_params, s);
}

static float64 float64_round_pack_canonical(FloatParts p, float_status *s)
{
    switch (p.cls) {
    case float_class_msnan:
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        p.frac >>= float64_params.frac_shift;
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        return float64_maybe_silence_nan(float64_pack_raw(p), s);
    default:
        p = round_canonical(p, s, &float64_params);
        return float64_pack_raw(p);
    }
}

/* Simple helpers for checking if what NaN we have */
static bool is_nan(FloatClass c)
{
    return unlikely(c >= float_class_qnan);
}
static bool is_snan(FloatClass c)
{
    return c == float_class_snan;
}
static bool is_qnan(FloatClass c)
{
    return c == float_class_qnan;
}

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static FloatParts return_nan(FloatParts a, float_status *s)
{
    switch (a.cls) {
    case float_class_snan:
        s->float_exception_flags |= float_flag_invalid;
        a.cls = float_class_msnan;
        /* fall through */
    case float_class_qnan:
        if (s->default_nan_mode) {
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            return parts_default_nan(s);
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        }
        break;

    default:
        g_assert_not_reached();
    }
    return a;
}

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static FloatParts pick_nan(FloatParts a, FloatParts b, float_status *s)
{
    if (is_snan(a.cls) || is_snan(b.cls)) {
        s->float_exception_flags |= float_flag_invalid;
    }

    if (s->default_nan_mode) {
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        return parts_default_nan(s);
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    } else {
        if (pickNaN(is_qnan(a.cls), is_snan(a.cls),
                    is_qnan(b.cls), is_snan(b.cls),
                    a.frac > b.frac ||
                    (a.frac == b.frac && a.sign < b.sign))) {
            a = b;
        }
        a.cls = float_class_msnan;
    }
    return a;
}

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static FloatParts pick_nan_muladd(FloatParts a, FloatParts b, FloatParts c,
                                  bool inf_zero, float_status *s)
{
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    int which;

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    if (is_snan(a.cls) || is_snan(b.cls) || is_snan(c.cls)) {
        s->float_exception_flags |= float_flag_invalid;
    }

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    which = pickNaNMulAdd(is_qnan(a.cls), is_snan(a.cls),
                          is_qnan(b.cls), is_snan(b.cls),
                          is_qnan(c.cls), is_snan(c.cls),
                          inf_zero, s);

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    if (s->default_nan_mode) {
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        /* Note that this check is after pickNaNMulAdd so that function
         * has an opportunity to set the Invalid flag.
         */
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        which = 3;
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    }
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    switch (which) {
    case 0:
        break;
    case 1:
        a = b;
        break;
    case 2:
        a = c;
        break;
    case 3:
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        return parts_default_nan(s);
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    default:
        g_assert_not_reached();
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    }
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    a.cls = float_class_msnan;

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    return a;
}

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

static FloatParts addsub_floats(FloatParts a, FloatParts b, bool subtract,
                                float_status *s)
{
    bool a_sign = a.sign;
    bool b_sign = b.sign ^ subtract;

    if (a_sign != b_sign) {
        /* Subtraction */

        if (a.cls == float_class_normal && b.cls == float_class_normal) {
            if (a.exp > b.exp || (a.exp == b.exp && a.frac >= b.frac)) {
                shift64RightJamming(b.frac, a.exp - b.exp, &b.frac);
                a.frac = a.frac - b.frac;
            } else {
                shift64RightJamming(a.frac, b.exp - a.exp, &a.frac);
                a.frac = b.frac - a.frac;
                a.exp = b.exp;
                a_sign ^= 1;
            }

            if (a.frac == 0) {
                a.cls = float_class_zero;
                a.sign = s->float_rounding_mode == float_round_down;
            } else {
                int shift = clz64(a.frac) - 1;
                a.frac = a.frac << shift;
                a.exp = a.exp - shift;
                a.sign = a_sign;
            }
            return a;
        }
        if (is_nan(a.cls) || is_nan(b.cls)) {
            return pick_nan(a, b, s);
        }
        if (a.cls == float_class_inf) {
            if (b.cls == float_class_inf) {
                float_raise(float_flag_invalid, s);
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                return parts_default_nan(s);
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            }
            return a;
        }
        if (a.cls == float_class_zero && b.cls == float_class_zero) {
            a.sign = s->float_rounding_mode == float_round_down;
            return a;
        }
        if (a.cls == float_class_zero || b.cls == float_class_inf) {
            b.sign = a_sign ^ 1;
            return b;
        }
        if (b.cls == float_class_zero) {
            return a;
        }
    } else {
        /* Addition */
        if (a.cls == float_class_normal && b.cls == float_class_normal) {
            if (a.exp > b.exp) {
                shift64RightJamming(b.frac, a.exp - b.exp, &b.frac);
            } else if (a.exp < b.exp) {
                shift64RightJamming(a.frac, b.exp - a.exp, &a.frac);
                a.exp = b.exp;
            }
            a.frac += b.frac;
            if (a.frac & DECOMPOSED_OVERFLOW_BIT) {
                a.frac >>= 1;
                a.exp += 1;
            }
            return a;
        }
        if (is_nan(a.cls) || is_nan(b.cls)) {
            return pick_nan(a, b, s);
        }
        if (a.cls == float_class_inf || b.cls == float_class_zero) {
            return a;
        }
        if (b.cls == float_class_inf || a.cls == float_class_zero) {
            b.sign = b_sign;
            return b;
        }
    }
    g_assert_not_reached();
}

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

float16  __attribute__((flatten)) float16_add(float16 a, float16 b,
                                              float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pb = float16_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, false, status);

    return float16_round_pack_canonical(pr, status);
}

float32 __attribute__((flatten)) float32_add(float32 a, float32 b,
                                             float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pb = float32_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, false, status);

    return float32_round_pack_canonical(pr, status);
}

float64 __attribute__((flatten)) float64_add(float64 a, float64 b,
                                             float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pb = float64_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, false, status);

    return float64_round_pack_canonical(pr, status);
}

float16 __attribute__((flatten)) float16_sub(float16 a, float16 b,
                                             float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pb = float16_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, true, status);

    return float16_round_pack_canonical(pr, status);
}

float32 __attribute__((flatten)) float32_sub(float32 a, float32 b,
                                             float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pb = float32_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, true, status);

    return float32_round_pack_canonical(pr, status);
}

float64 __attribute__((flatten)) float64_sub(float64 a, float64 b,
                                             float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pb = float64_unpack_canonical(b, status);
    FloatParts pr = addsub_floats(pa, pb, true, status);

    return float64_round_pack_canonical(pr, status);
}

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

static FloatParts mul_floats(FloatParts a, FloatParts b, float_status *s)
{
    bool sign = a.sign ^ b.sign;

    if (a.cls == float_class_normal && b.cls == float_class_normal) {
        uint64_t hi, lo;
        int exp = a.exp + b.exp;

        mul64To128(a.frac, b.frac, &hi, &lo);
        shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo);
        if (lo & DECOMPOSED_OVERFLOW_BIT) {
            shift64RightJamming(lo, 1, &lo);
            exp += 1;
        }

        /* Re-use a */
        a.exp = exp;
        a.sign = sign;
        a.frac = lo;
        return a;
    }
    /* handle all the NaN cases */
    if (is_nan(a.cls) || is_nan(b.cls)) {
        return pick_nan(a, b, s);
    }
    /* Inf * Zero == NaN */
    if ((a.cls == float_class_inf && b.cls == float_class_zero) ||
        (a.cls == float_class_zero && b.cls == float_class_inf)) {
        s->float_exception_flags |= float_flag_invalid;
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        return parts_default_nan(s);
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    }
    /* Multiply by 0 or Inf */
    if (a.cls == float_class_inf || a.cls == float_class_zero) {
        a.sign = sign;
        return a;
    }
    if (b.cls == float_class_inf || b.cls == float_class_zero) {
        b.sign = sign;
        return b;
    }
    g_assert_not_reached();
}

float16 __attribute__((flatten)) float16_mul(float16 a, float16 b,
                                             float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pb = float16_unpack_canonical(b, status);
    FloatParts pr = mul_floats(pa, pb, status);

    return float16_round_pack_canonical(pr, status);
}

float32 __attribute__((flatten)) float32_mul(float32 a, float32 b,
                                             float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pb = float32_unpack_canonical(b, status);
    FloatParts pr = mul_floats(pa, pb, status);

    return float32_round_pack_canonical(pr, status);
}

float64 __attribute__((flatten)) float64_mul(float64 a, float64 b,
                                             float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pb = float64_unpack_canonical(b, status);
    FloatParts pr = mul_floats(pa, pb, status);

    return float64_round_pack_canonical(pr, status);
}

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/*
 * Returns the result of multiplying the floating-point values `a' and
 * `b' then adding 'c', with no intermediate rounding step after the
 * multiplication. The operation is performed according to the
 * IEC/IEEE Standard for Binary Floating-Point Arithmetic 754-2008.
 * The flags argument allows the caller to select negation of the
 * addend, the intermediate product, or the final result. (The
 * difference between this and having the caller do a separate
 * negation is that negating externally will flip the sign bit on
 * NaNs.)
 */

static FloatParts muladd_floats(FloatParts a, FloatParts b, FloatParts c,
                                int flags, float_status *s)
{
    bool inf_zero = ((1 << a.cls) | (1 << b.cls)) ==
                    ((1 << float_class_inf) | (1 << float_class_zero));
    bool p_sign;
    bool sign_flip = flags & float_muladd_negate_result;
    FloatClass p_class;
    uint64_t hi, lo;
    int p_exp;

    /* It is implementation-defined whether the cases of (0,inf,qnan)
     * and (inf,0,qnan) raise InvalidOperation or not (and what QNaN
     * they return if they do), so we have to hand this information
     * off to the target-specific pick-a-NaN routine.
     */
    if (is_nan(a.cls) || is_nan(b.cls) || is_nan(c.cls)) {
        return pick_nan_muladd(a, b, c, inf_zero, s);
    }

    if (inf_zero) {
        s->float_exception_flags |= float_flag_invalid;
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        return parts_default_nan(s);
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    }

    if (flags & float_muladd_negate_c) {
        c.sign ^= 1;
    }

    p_sign = a.sign ^ b.sign;

    if (flags & float_muladd_negate_product) {
        p_sign ^= 1;
    }

    if (a.cls == float_class_inf || b.cls == float_class_inf) {
        p_class = float_class_inf;
    } else if (a.cls == float_class_zero || b.cls == float_class_zero) {
        p_class = float_class_zero;
    } else {
        p_class = float_class_normal;
    }

    if (c.cls == float_class_inf) {
        if (p_class == float_class_inf && p_sign != c.sign) {
            s->float_exception_flags |= float_flag_invalid;
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            return parts_default_nan(s);
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        } else {
            a.cls = float_class_inf;
            a.sign = c.sign ^ sign_flip;
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            return a;
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        }
    }

    if (p_class == float_class_inf) {
        a.cls = float_class_inf;
        a.sign = p_sign ^ sign_flip;
        return a;
    }

    if (p_class == float_class_zero) {
        if (c.cls == float_class_zero) {
            if (p_sign != c.sign) {
                p_sign = s->float_rounding_mode == float_round_down;
            }
            c.sign = p_sign;
        } else if (flags & float_muladd_halve_result) {
            c.exp -= 1;
        }
        c.sign ^= sign_flip;
        return c;
    }

    /* a & b should be normals now... */
    assert(a.cls == float_class_normal &&
           b.cls == float_class_normal);

    p_exp = a.exp + b.exp;

    /* Multiply of 2 62-bit numbers produces a (2*62) == 124-bit
     * result.
     */
    mul64To128(a.frac, b.frac, &hi, &lo);
    /* binary point now at bit 124 */

    /* check for overflow */
    if (hi & (1ULL << (DECOMPOSED_BINARY_POINT * 2 + 1 - 64))) {
        shift128RightJamming(hi, lo, 1, &hi, &lo);
        p_exp += 1;
    }

    /* + add/sub */
    if (c.cls == float_class_zero) {
        /* move binary point back to 62 */
        shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo);
    } else {
        int exp_diff = p_exp - c.exp;
        if (p_sign == c.sign) {
            /* Addition */
            if (exp_diff <= 0) {
                shift128RightJamming(hi, lo,
                                     DECOMPOSED_BINARY_POINT - exp_diff,
                                     &hi, &lo);
                lo += c.frac;
                p_exp = c.exp;
            } else {
                uint64_t c_hi, c_lo;
                /* shift c to the same binary point as the product (124) */
                c_hi = c.frac >> 2;
                c_lo = 0;
                shift128RightJamming(c_hi, c_lo,
                                     exp_diff,
                                     &c_hi, &c_lo);
                add128(hi, lo, c_hi, c_lo, &hi, &lo);
                /* move binary point back to 62 */
                shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo);
            }

            if (lo & DECOMPOSED_OVERFLOW_BIT) {
                shift64RightJamming(lo, 1, &lo);
                p_exp += 1;
            }

        } else {
            /* Subtraction */
            uint64_t c_hi, c_lo;
            /* make C binary point match product at bit 124 */
            c_hi = c.frac >> 2;
            c_lo = 0;

            if (exp_diff <= 0) {
                shift128RightJamming(hi, lo, -exp_diff, &hi, &lo);
                if (exp_diff == 0
                    &&
                    (hi > c_hi || (hi == c_hi && lo >= c_lo))) {
                    sub128(hi, lo, c_hi, c_lo, &hi, &lo);
                } else {
                    sub128(c_hi, c_lo, hi, lo, &hi, &lo);
                    p_sign ^= 1;
                    p_exp = c.exp;
                }
            } else {
                shift128RightJamming(c_hi, c_lo,
                                     exp_diff,
                                     &c_hi, &c_lo);
                sub128(hi, lo, c_hi, c_lo, &hi, &lo);
            }

            if (hi == 0 && lo == 0) {
                a.cls = float_class_zero;
                a.sign = s->float_rounding_mode == float_round_down;
                a.sign ^= sign_flip;
                return a;
            } else {
                int shift;
                if (hi != 0) {
                    shift = clz64(hi);
                } else {
                    shift = clz64(lo) + 64;
                }
                /* Normalizing to a binary point of 124 is the
                   correct adjust for the exponent.  However since we're
                   shifting, we might as well put the binary point back
                   at 62 where we really want it.  Therefore shift as
                   if we're leaving 1 bit at the top of the word, but
                   adjust the exponent as if we're leaving 3 bits.  */
                shift -= 1;
                if (shift >= 64) {
                    lo = lo << (shift - 64);
                } else {
                    hi = (hi << shift) | (lo >> (64 - shift));
                    lo = hi | ((lo << shift) != 0);
                }
                p_exp -= shift - 2;
            }
        }
    }

    if (flags & float_muladd_halve_result) {
        p_exp -= 1;
    }

    /* finally prepare our result */
    a.cls = float_class_normal;
    a.sign = p_sign ^ sign_flip;
    a.exp = p_exp;
    a.frac = lo;

    return a;
}

float16 __attribute__((flatten)) float16_muladd(float16 a, float16 b, float16 c,
                                                int flags, float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pb = float16_unpack_canonical(b, status);
    FloatParts pc = float16_unpack_canonical(c, status);
    FloatParts pr = muladd_floats(pa, pb, pc, flags, status);

    return float16_round_pack_canonical(pr, status);
}

float32 __attribute__((flatten)) float32_muladd(float32 a, float32 b, float32 c,
                                                int flags, float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pb = float32_unpack_canonical(b, status);
    FloatParts pc = float32_unpack_canonical(c, status);
    FloatParts pr = muladd_floats(pa, pb, pc, flags, status);

    return float32_round_pack_canonical(pr, status);
}

float64 __attribute__((flatten)) float64_muladd(float64 a, float64 b, float64 c,
                                                int flags, float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pb = float64_unpack_canonical(b, status);
    FloatParts pc = float64_unpack_canonical(c, status);
    FloatParts pr = muladd_floats(pa, pb, pc, flags, status);

    return float64_round_pack_canonical(pr, status);
}

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

static FloatParts div_floats(FloatParts a, FloatParts b, float_status *s)
{
    bool sign = a.sign ^ b.sign;

    if (a.cls == float_class_normal && b.cls == float_class_normal) {
        uint64_t temp_lo, temp_hi;
        int exp = a.exp - b.exp;
        if (a.frac < b.frac) {
            exp -= 1;
            shortShift128Left(0, a.frac, DECOMPOSED_BINARY_POINT + 1,
                              &temp_hi, &temp_lo);
        } else {
            shortShift128Left(0, a.frac, DECOMPOSED_BINARY_POINT,
                              &temp_hi, &temp_lo);
        }
        /* LSB of quot is set if inexact which roundandpack will use
         * to set flags. Yet again we re-use a for the result */
        a.frac = div128To64(temp_lo, temp_hi, b.frac);
        a.sign = sign;
        a.exp = exp;
        return a;
    }
    /* handle all the NaN cases */
    if (is_nan(a.cls) || is_nan(b.cls)) {
        return pick_nan(a, b, s);
    }
    /* 0/0 or Inf/Inf */
    if (a.cls == b.cls
        &&
        (a.cls == float_class_inf || a.cls == float_class_zero)) {
        s->float_exception_flags |= float_flag_invalid;
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        return parts_default_nan(s);
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    }
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    /* Inf / x or 0 / x */
    if (a.cls == float_class_inf || a.cls == float_class_zero) {
        a.sign = sign;
        return a;
    }
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    /* Div 0 => Inf */
    if (b.cls == float_class_zero) {
        s->float_exception_flags |= float_flag_divbyzero;
        a.cls = float_class_inf;
        a.sign = sign;
        return a;
    }
    /* Div by Inf */
    if (b.cls == float_class_inf) {
        a.cls = float_class_zero;
        a.sign = sign;
        return a;
    }
    g_assert_not_reached();
}

float16 float16_div(float16 a, float16 b, float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pb = float16_unpack_canonical(b, status);
    FloatParts pr = div_floats(pa, pb, status);

    return float16_round_pack_canonical(pr, status);
}

float32 float32_div(float32 a, float32 b, float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pb = float32_unpack_canonical(b, status);
    FloatParts pr = div_floats(pa, pb, status);

    return float32_round_pack_canonical(pr, status);
}

float64 float64_div(float64 a, float64 b, float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pb = float64_unpack_canonical(b, status);
    FloatParts pr = div_floats(pa, pb, status);

    return float64_round_pack_canonical(pr, status);
}

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

static FloatParts round_to_int(FloatParts a, int rounding_mode, float_status *s)
{
    if (is_nan(a.cls)) {
        return return_nan(a, s);
    }

    switch (a.cls) {
    case float_class_zero:
    case float_class_inf:
    case float_class_qnan:
        /* already "integral" */
        break;
    case float_class_normal:
        if (a.exp >= DECOMPOSED_BINARY_POINT) {
            /* already integral */
            break;
        }
        if (a.exp < 0) {
            bool one;
            /* all fractional */
            s->float_exception_flags |= float_flag_inexact;
            switch (rounding_mode) {
            case float_round_nearest_even:
                one = a.exp == -1 && a.frac > DECOMPOSED_IMPLICIT_BIT;
                break;
            case float_round_ties_away:
                one = a.exp == -1 && a.frac >= DECOMPOSED_IMPLICIT_BIT;
                break;
            case float_round_to_zero:
                one = false;
                break;
            case float_round_up:
                one = !a.sign;
                break;
            case float_round_down:
                one = a.sign;
                break;
            default:
                g_assert_not_reached();
            }

            if (one) {
                a.frac = DECOMPOSED_IMPLICIT_BIT;
                a.exp = 0;
            } else {
                a.cls = float_class_zero;
            }
        } else {
            uint64_t frac_lsb = DECOMPOSED_IMPLICIT_BIT >> a.exp;
            uint64_t frac_lsbm1 = frac_lsb >> 1;
            uint64_t rnd_even_mask = (frac_lsb - 1) | frac_lsb;
            uint64_t rnd_mask = rnd_even_mask >> 1;
            uint64_t inc;

            switch (rounding_mode) {
            case float_round_nearest_even:
                inc = ((a.frac & rnd_even_mask) != frac_lsbm1 ? frac_lsbm1 : 0);
                break;
            case float_round_ties_away:
                inc = frac_lsbm1;
                break;
            case float_round_to_zero:
                inc = 0;
                break;
            case float_round_up:
                inc = a.sign ? 0 : rnd_mask;
                break;
            case float_round_down:
                inc = a.sign ? rnd_mask : 0;
                break;
            default:
                g_assert_not_reached();
            }

            if (a.frac & rnd_mask) {
                s->float_exception_flags |= float_flag_inexact;
                a.frac += inc;
                a.frac &= ~rnd_mask;
                if (a.frac & DECOMPOSED_OVERFLOW_BIT) {
                    a.frac >>= 1;
                    a.exp++;
                }
            }
        }
        break;
    default:
        g_assert_not_reached();
    }
    return a;
}

float16 float16_round_to_int(float16 a, float_status *s)
{
    FloatParts pa = float16_unpack_canonical(a, s);
    FloatParts pr = round_to_int(pa, s->float_rounding_mode, s);
    return float16_round_pack_canonical(pr, s);
}

float32 float32_round_to_int(float32 a, float_status *s)
{
    FloatParts pa = float32_unpack_canonical(a, s);
    FloatParts pr = round_to_int(pa, s->float_rounding_mode, s);
    return float32_round_pack_canonical(pr, s);
}

float64 float64_round_to_int(float64 a, float_status *s)
{
    FloatParts pa = float64_unpack_canonical(a, s);
    FloatParts pr = round_to_int(pa, s->float_rounding_mode, s);
    return float64_round_pack_canonical(pr, s);
}

float64 float64_trunc_to_int(float64 a, float_status *s)
{
    FloatParts pa = float64_unpack_canonical(a, s);
    FloatParts pr = round_to_int(pa, float_round_to_zero, s);
    return float64_round_pack_canonical(pr, s);
}

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/*
 * Returns the result of converting the floating-point value `a' to
 * the 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.
*/

static int64_t round_to_int_and_pack(FloatParts in, int rmode,
                                     int64_t min, int64_t max,
                                     float_status *s)
{
    uint64_t r;
    int orig_flags = get_float_exception_flags(s);
    FloatParts p = round_to_int(in, rmode, s);

    switch (p.cls) {
    case float_class_snan:
    case float_class_qnan:
1337
    case float_class_msnan:
1338
        s->float_exception_flags = orig_flags | float_flag_invalid;
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        return max;
    case float_class_inf:
1341
        s->float_exception_flags = orig_flags | float_flag_invalid;
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        return p.sign ? min : max;
    case float_class_zero:
        return 0;
    case float_class_normal:
        if (p.exp < DECOMPOSED_BINARY_POINT) {
            r = p.frac >> (DECOMPOSED_BINARY_POINT - p.exp);
        } else if (p.exp - DECOMPOSED_BINARY_POINT < 2) {
            r = p.frac << (p.exp - DECOMPOSED_BINARY_POINT);
        } else {
            r = UINT64_MAX;
        }
        if (p.sign) {
1354
            if (r <= -(uint64_t) min) {
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                return -r;
            } else {
                s->float_exception_flags = orig_flags | float_flag_invalid;
                return min;
            }
        } else {
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            if (r <= max) {
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                return r;
            } else {
                s->float_exception_flags = orig_flags | float_flag_invalid;
                return max;
            }
        }
    default:
        g_assert_not_reached();
    }
}

#define FLOAT_TO_INT(fsz, isz)                                          \
int ## isz ## _t float ## fsz ## _to_int ## isz(float ## fsz a,         \
                                                float_status *s)        \
{                                                                       \
    FloatParts p = float ## fsz ## _unpack_canonical(a, s);             \
    return round_to_int_and_pack(p, s->float_rounding_mode,             \
                                 INT ## isz ## _MIN, INT ## isz ## _MAX,\
                                 s);                                    \
}                                                                       \
                                                                        \
int ## isz ## _t float ## fsz ## _to_int ## isz ## _round_to_zero       \
 (float ## fsz a, float_status *s)                                      \
{                                                                       \
    FloatParts p = float ## fsz ## _unpack_canonical(a, s);             \
    return round_to_int_and_pack(p, float_round_to_zero,                \
                                 INT ## isz ## _MIN, INT ## isz ## _MAX,\
                                 s);                                    \
}

FLOAT_TO_INT(16, 16)
FLOAT_TO_INT(16, 32)
FLOAT_TO_INT(16, 64)

FLOAT_TO_INT(32, 16)
FLOAT_TO_INT(32, 32)
FLOAT_TO_INT(32, 64)

FLOAT_TO_INT(64, 16)
FLOAT_TO_INT(64, 32)
FLOAT_TO_INT(64, 64)

#undef FLOAT_TO_INT

/*
 *  Returns the result of converting the floating-point value `a' to
 *  the unsigned 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 unsigned integer is returned. Otherwise, if the
 *  conversion overflows, the largest unsigned integer is returned. If
 *  the 'a' is negative, the result is rounded and zero is returned;
 *  values that do not round to zero will raise the inexact exception
 *  flag.
 */

static uint64_t round_to_uint_and_pack(FloatParts in, int rmode, uint64_t max,
                                       float_status *s)
{
    int orig_flags = get_float_exception_flags(s);
    FloatParts p = round_to_int(in, rmode, s);

    switch (p.cls) {
    case float_class_snan:
    case float_class_qnan:
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    case float_class_msnan:
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        s->float_exception_flags = orig_flags | float_flag_invalid;
        return max;
    case float_class_inf:
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        s->float_exception_flags = orig_flags | float_flag_invalid;
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        return p.sign ? 0 : max;
    case float_class_zero:
        return 0;
    case float_class_normal:
    {
        uint64_t r;
        if (p.sign) {
            s->float_exception_flags = orig_flags | float_flag_invalid;
            return 0;
        }

        if (p.exp < DECOMPOSED_BINARY_POINT) {
            r = p.frac >> (DECOMPOSED_BINARY_POINT - p.exp);
        } else if (p.exp - DECOMPOSED_BINARY_POINT < 2) {
            r = p.frac << (p.exp - DECOMPOSED_BINARY_POINT);
        } else {
            s->float_exception_flags = orig_flags | float_flag_invalid;
            return max;
        }

        /* For uint64 this will never trip, but if p.exp is too large
         * to shift a decomposed fraction we shall have exited via the
         * 3rd leg above.
         */
        if (r > max) {
            s->float_exception_flags = orig_flags | float_flag_invalid;
            return max;
        } else {
            return r;
        }
    }
    default:
        g_assert_not_reached();
    }
}

#define FLOAT_TO_UINT(fsz, isz) \
uint ## isz ## _t float ## fsz ## _to_uint ## isz(float ## fsz a,       \
                                                  float_status *s)      \
{                                                                       \
    FloatParts p = float ## fsz ## _unpack_canonical(a, s);             \
    return round_to_uint_and_pack(p, s->float_rounding_mode,            \
                                 UINT ## isz ## _MAX, s);               \
}                                                                       \
                                                                        \
uint ## isz ## _t float ## fsz ## _to_uint ## isz ## _round_to_zero     \
 (float ## fsz a, float_status *s)                                      \
{                                                                       \
    FloatParts p = float ## fsz ## _unpack_canonical(a, s);             \
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    return round_to_uint_and_pack(p, float_round_to_zero,               \
                                  UINT ## isz ## _MAX, s);              \
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}

FLOAT_TO_UINT(16, 16)
FLOAT_TO_UINT(16, 32)
FLOAT_TO_UINT(16, 64)

FLOAT_TO_UINT(32, 16)
FLOAT_TO_UINT(32, 32)
FLOAT_TO_UINT(32, 64)

FLOAT_TO_UINT(64, 16)
FLOAT_TO_UINT(64, 32)
FLOAT_TO_UINT(64, 64)

#undef FLOAT_TO_UINT

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

static FloatParts int_to_float(int64_t a, float_status *status)
{
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    FloatParts r = {};
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    if (a == 0) {
        r.cls = float_class_zero;
        r.sign = false;
    } else if (a == (1ULL << 63)) {
        r.cls = float_class_normal;
        r.sign = true;
        r.frac = DECOMPOSED_IMPLICIT_BIT;
        r.exp = 63;
    } else {
        uint64_t f;
        if (a < 0) {
            f = -a;
            r.sign = true;
        } else {
            f = a;
            r.sign = false;
        }
        int shift = clz64(f) - 1;
        r.cls = float_class_normal;
        r.exp = (DECOMPOSED_BINARY_POINT - shift);
        r.frac = f << shift;
    }

    return r;
}

float16 int64_to_float16(int64_t a, float_status *status)
{
    FloatParts pa = int_to_float(a, status);
    return float16_round_pack_canonical(pa, status);
}

float16 int32_to_float16(int32_t a, float_status *status)
{
    return int64_to_float16(a, status);
}

float16 int16_to_float16(int16_t a, float_status *status)
{
    return int64_to_float16(a, status);
}

float32 int64_to_float32(int64_t a, float_status *status)
{
    FloatParts pa = int_to_float(a, status);
    return float32_round_pack_canonical(pa, status);
}

float32 int32_to_float32(int32_t a, float_status *status)
{
    return int64_to_float32(a, status);
}

float32 int16_to_float32(int16_t a, float_status *status)
{
    return int64_to_float32(a, status);
}

float64 int64_to_float64(int64_t a, float_status *status)
{
    FloatParts pa = int_to_float(a, status);
    return float64_round_pack_canonical(pa, status);
}

float64 int32_to_float64(int32_t a, float_status *status)
{
    return int64_to_float64(a, status);
}

float64 int16_to_float64(int16_t a, float_status *status)
{
    return int64_to_float64(a, status);
}


/*
 * Unsigned Integer to float conversions
 *
 * Returns the result of converting the unsigned integer `a' to the
 * floating-point format. The conversion is performed according to the
 * IEC/IEEE Standard for Binary Floating-Point Arithmetic.
 */

static FloatParts uint_to_float(uint64_t a, float_status *status)
{
    FloatParts r = { .sign = false};

    if (a == 0) {
        r.cls = float_class_zero;
    } else {
        int spare_bits = clz64(a) - 1;
        r.cls = float_class_normal;
        r.exp = DECOMPOSED_BINARY_POINT - spare_bits;
        if (spare_bits < 0) {
            shift64RightJamming(a, -spare_bits, &a);
            r.frac = a;
        } else {
            r.frac = a << spare_bits;
        }
    }

    return r;
}

float16 uint64_to_float16(uint64_t a, float_status *status)
{
    FloatParts pa = uint_to_float(a, status);
    return float16_round_pack_canonical(pa, status);
}

float16 uint32_to_float16(uint32_t a, float_status *status)
{
    return uint64_to_float16(a, status);
}

float16 uint16_to_float16(uint16_t a, float_status *status)
{
    return uint64_to_float16(a, status);
}

float32 uint64_to_float32(uint64_t a, float_status *status)
{
    FloatParts pa = uint_to_float(a, status);
    return float32_round_pack_canonical(pa, status);
}

float32 uint32_to_float32(uint32_t a, float_status *status)
{
    return uint64_to_float32(a, status);
}

float32 uint16_to_float32(uint16_t a, float_status *status)
{
    return uint64_to_float32(a, status);
}

float64 uint64_to_float64(uint64_t a, float_status *status)
{
    FloatParts pa = uint_to_float(a, status);
    return float64_round_pack_canonical(pa, status);
}

float64 uint32_to_float64(uint32_t a, float_status *status)
{
    return uint64_to_float64(a, status);
}

float64 uint16_to_float64(uint16_t a, float_status *status)
{
    return uint64_to_float64(a, status);
}

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/* Float Min/Max */
/* min() and max() functions. These can't be implemented as
 * 'compare and pick one input' because that would mishandle
 * NaNs and +0 vs -0.
 *
 * minnum() and maxnum() functions. These are similar to the min()
 * and max() functions but if one of the arguments is a QNaN and
 * the other is numerical then the numerical argument is returned.
 * SNaNs will get quietened before being returned.
 * minnum() and maxnum correspond to the IEEE 754-2008 minNum()
 * and maxNum() operations. min() and max() are the typical min/max
 * semantics provided by many CPUs which predate that specification.
 *
 * minnummag() and maxnummag() functions correspond to minNumMag()
 * and minNumMag() from the IEEE-754 2008.
 */
static FloatParts minmax_floats(FloatParts a, FloatParts b, bool ismin,
                                bool ieee, bool ismag, float_status *s)
{
    if (unlikely(is_nan(a.cls) || is_nan(b.cls))) {
        if (ieee) {
            /* Takes two floating-point values `a' and `b', one of
             * which is a NaN, and returns the appropriate NaN
             * result. If either `a' or `b' is a signaling NaN,
             * the invalid exception is raised.
             */
            if (is_snan(a.cls) || is_snan(b.cls)) {
                return pick_nan(a, b, s);
            } else if (is_nan(a.cls) && !is_nan(b.cls)) {
                return b;
            } else if (is_nan(b.cls) && !is_nan(a.cls)) {
                return a;
            }
        }
        return pick_nan(a, b, s);
    } else {
        int a_exp, b_exp;

        switch (a.cls) {
        case float_class_normal:
            a_exp = a.exp;
            break;
        case float_class_inf:
            a_exp = INT_MAX;
            break;
        case float_class_zero:
            a_exp = INT_MIN;
            break;
        default:
            g_assert_not_reached();
            break;
        }
        switch (b.cls) {
        case float_class_normal:
            b_exp = b.exp;
            break;
        case float_class_inf:
            b_exp = INT_MAX;
            break;
        case float_class_zero:
            b_exp = INT_MIN;
            break;
        default:
            g_assert_not_reached();
            break;
        }

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        if (ismag && (a_exp != b_exp || a.frac != b.frac)) {
            bool a_less = a_exp < b_exp;
            if (a_exp == b_exp) {
                a_less = a.frac < b.frac;
            }
            return a_less ^ ismin ? b : a;
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        }

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        if (a.sign == b.sign) {
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            bool a_less = a_exp < b_exp;
            if (a_exp == b_exp) {
                a_less = a.frac < b.frac;
            }
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            return a.sign ^ a_less ^ ismin ? b : a;
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        } else {
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            return a.sign ^ ismin ? b : a;
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        }
    }
}

#define MINMAX(sz, name, ismin, isiee, ismag)                           \
float ## sz float ## sz ## _ ## name(float ## sz a, float ## sz b,      \
                                     float_status *s)                   \
{                                                                       \
    FloatParts pa = float ## sz ## _unpack_canonical(a, s);             \
    FloatParts pb = float ## sz ## _unpack_canonical(b, s);             \
    FloatParts pr = minmax_floats(pa, pb, ismin, isiee, ismag, s);      \
                                                                        \
    return float ## sz ## _round_pack_canonical(pr, s);                 \
}

MINMAX(16, min, true, false, false)
MINMAX(16, minnum, true, true, false)
MINMAX(16, minnummag, true, true, true)
MINMAX(16, max, false, false, false)
MINMAX(16, maxnum, false, true, false)
MINMAX(16, maxnummag, false, true, true)

MINMAX(32, min, true, false, false)
MINMAX(32, minnum, true, true, false)
MINMAX(32, minnummag, true, true, true)
MINMAX(32, max, false, false, false)
MINMAX(32, maxnum, false, true, false)
MINMAX(32, maxnummag, false, true, true)

MINMAX(64, min, true, false, false)
MINMAX(64, minnum, true, true, false)
MINMAX(64, minnummag, true, true, true)
MINMAX(64, max, false, false, false)
MINMAX(64, maxnum, false, true, false)
MINMAX(64, maxnummag, false, true, true)

#undef MINMAX

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/* Floating point compare */
static int compare_floats(FloatParts a, FloatParts b, bool is_quiet,
                          float_status *s)
{
    if (is_nan(a.cls) || is_nan(b.cls)) {
        if (!is_quiet ||
            a.cls == float_class_snan ||
            b.cls == float_class_snan) {
            s->float_exception_flags |= float_flag_invalid;
        }
        return float_relation_unordered;
    }

    if (a.cls == float_class_zero) {
        if (b.cls == float_class_zero) {
            return float_relation_equal;
        }
        return b.sign ? float_relation_greater : float_relation_less;
    } else if (b.cls == float_class_zero) {
        return a.sign ? float_relation_less : float_relation_greater;
    }

    /* The only really important thing about infinity is its sign. If
     * both are infinities the sign marks the smallest of the two.
     */
    if (a.cls == float_class_inf) {
        if ((b.cls == float_class_inf) && (a.sign == b.sign)) {
            return float_relation_equal;
        }
        return a.sign ? float_relation_less : float_relation_greater;
    } else if (b.cls == float_class_inf) {
        return b.sign ? float_relation_greater : float_relation_less;
    }

    if (a.sign != b.sign) {
        return a.sign ? float_relation_less : float_relation_greater;
    }

    if (a.exp == b.exp) {
        if (a.frac == b.frac) {
            return float_relation_equal;
        }
        if (a.sign) {
            return a.frac > b.frac ?
                float_relation_less : float_relation_greater;
        } else {
            return a.frac > b.frac ?
                float_relation_greater : float_relation_less;
        }
    } else {
        if (a.sign) {
            return a.exp > b.exp ? float_relation_less : float_relation_greater;
        } else {
            return a.exp > b.exp ? float_relation_greater : float_relation_less;
        }
    }
}

#define COMPARE(sz)                                                     \
int float ## sz ## _compare(float ## sz a, float ## sz b,               \
                            float_status *s)                            \
{                                                                       \
    FloatParts pa = float ## sz ## _unpack_canonical(a, s);             \
    FloatParts pb = float ## sz ## _unpack_canonical(b, s);             \
    return compare_floats(pa, pb, false, s);                            \
}                                                                       \
int float ## sz ## _compare_quiet(float ## sz a, float ## sz b,         \
                                  float_status *s)                      \
{                                                                       \
    FloatParts pa = float ## sz ## _unpack_canonical(a, s);             \
    FloatParts pb = float ## sz ## _unpack_canonical(b, s);             \
    return compare_floats(pa, pb, true, s);                             \
}

COMPARE(16)
COMPARE(32)
COMPARE(64)

#undef COMPARE

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/* Multiply A by 2 raised to the power N.  */
static FloatParts scalbn_decomposed(FloatParts a, int n, float_status *s)
{
    if (unlikely(is_nan(a.cls))) {
        return return_nan(a, s);
    }
    if (a.cls == float_class_normal) {
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        /* The largest float type (even though not supported by FloatParts)
         * is float128, which has a 15 bit exponent.  Bounding N to 16 bits
         * still allows rounding to infinity, without allowing overflow
         * within the int32_t that backs FloatParts.exp.
         */
        n = MIN(MAX(n, -0x10000), 0x10000);
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        a.exp += n;
    }
    return a;
}

float16 float16_scalbn(float16 a, int n, float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pr = scalbn_decomposed(pa, n, status);
    return float16_round_pack_canonical(pr, status);
}

float32 float32_scalbn(float32 a, int n, float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pr = scalbn_decomposed(pa, n, status);
    return float32_round_pack_canonical(pr, status);
}

float64 float64_scalbn(float64 a, int n, float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pr = scalbn_decomposed(pa, n, status);
    return float64_round_pack_canonical(pr, status);
}

A
Alex Bennée 已提交
1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927
/*
 * Square Root
 *
 * The old softfloat code did an approximation step before zeroing in
 * on the final result. However for simpleness we just compute the
 * square root by iterating down from the implicit bit to enough extra
 * bits to ensure we get a correctly rounded result.
 *
 * This does mean however the calculation is slower than before,
 * especially for 64 bit floats.
 */

static FloatParts sqrt_float(FloatParts a, float_status *s, const FloatFmt *p)
{
    uint64_t a_frac, r_frac, s_frac;
    int bit, last_bit;

    if (is_nan(a.cls)) {
        return return_nan(a, s);
    }
    if (a.cls == float_class_zero) {
        return a;  /* sqrt(+-0) = +-0 */
    }
    if (a.sign) {
        s->float_exception_flags |= float_flag_invalid;
1928
        return parts_default_nan(s);
A
Alex Bennée 已提交
1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
    }
    if (a.cls == float_class_inf) {
        return a;  /* sqrt(+inf) = +inf */
    }

    assert(a.cls == float_class_normal);

    /* We need two overflow bits at the top. Adding room for that is a
     * right shift. If the exponent is odd, we can discard the low bit
     * by multiplying the fraction by 2; that's a left shift. Combine
     * those and we shift right if the exponent is even.
     */
    a_frac = a.frac;
    if (!(a.exp & 1)) {
        a_frac >>= 1;
    }
    a.exp >>= 1;

    /* Bit-by-bit computation of sqrt.  */
    r_frac = 0;
    s_frac = 0;

    /* Iterate from implicit bit down to the 3 extra bits to compute a
     * properly rounded result. Remember we've inserted one more bit
     * at the top, so these positions are one less.
     */
    bit = DECOMPOSED_BINARY_POINT - 1;
    last_bit = MAX(p->frac_shift - 4, 0);
    do {
        uint64_t q = 1ULL << bit;
        uint64_t t_frac = s_frac + q;
        if (t_frac <= a_frac) {
            s_frac = t_frac + q;
            a_frac -= t_frac;
            r_frac += q;
        }
        a_frac <<= 1;
    } while (--bit >= last_bit);

    /* Undo the right shift done above. If there is any remaining
     * fraction, the result is inexact. Set the sticky bit.
     */
    a.frac = (r_frac << 1) + (a_frac != 0);

    return a;
}

float16 __attribute__((flatten)) float16_sqrt(float16 a, float_status *status)
{
    FloatParts pa = float16_unpack_canonical(a, status);
    FloatParts pr = sqrt_float(pa, status, &float16_params);
    return float16_round_pack_canonical(pr, status);
}

float32 __attribute__((flatten)) float32_sqrt(float32 a, float_status *status)
{
    FloatParts pa = float32_unpack_canonical(a, status);
    FloatParts pr = sqrt_float(pa, status, &float32_params);
    return float32_round_pack_canonical(pr, status);
}

float64 __attribute__((flatten)) float64_sqrt(float64 a, float_status *status)
{
    FloatParts pa = float64_unpack_canonical(a, status);
    FloatParts pr = sqrt_float(pa, status, &float64_params);
    return float64_round_pack_canonical(pr, status);
}


B
bellard 已提交
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
/*----------------------------------------------------------------------------
| Takes a 64-bit fixed-point value `absZ' with binary point between bits 6
| and 7, and returns the properly rounded 32-bit integer corresponding to the
| input.  If `zSign' is 1, the input is negated before being converted to an
| integer.  Bit 63 of `absZ' must be zero.  Ordinarily, the fixed-point input
| is simply rounded to an integer, with the inexact exception raised if the
| input cannot be represented exactly as an integer.  However, if the fixed-
| point input is too large, the invalid exception is raised and the largest
| positive or negative integer is returned.
*----------------------------------------------------------------------------*/

2009
static int32_t roundAndPackInt32(flag zSign, uint64_t absZ, float_status *status)
B
bellard 已提交
2010
{
2011
    int8_t roundingMode;
B
bellard 已提交
2012
    flag roundNearestEven;
2013
    int8_t roundIncrement, roundBits;
2014
    int32_t z;
B
bellard 已提交
2015

2016
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2017
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2018 2019
    switch (roundingMode) {
    case float_round_nearest_even:
2020
    case float_round_ties_away:
2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
        roundIncrement = 0x40;
        break;
    case float_round_to_zero:
        roundIncrement = 0;
        break;
    case float_round_up:
        roundIncrement = zSign ? 0 : 0x7f;
        break;
    case float_round_down:
        roundIncrement = zSign ? 0x7f : 0;
        break;
    default:
        abort();
B
bellard 已提交
2034 2035 2036 2037 2038 2039 2040
    }
    roundBits = absZ & 0x7F;
    absZ = ( absZ + roundIncrement )>>7;
    absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven );
    z = absZ;
    if ( zSign ) z = - z;
    if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) {
P
Peter Maydell 已提交
2041
        float_raise(float_flag_invalid, status);
2042
        return zSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
2043
    }
2044 2045 2046
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062
    return z;

}

/*----------------------------------------------------------------------------
| Takes the 128-bit fixed-point value formed by concatenating `absZ0' and
| `absZ1', with binary point between bits 63 and 64 (between the input words),
| and returns the properly rounded 64-bit integer corresponding to the input.
| If `zSign' is 1, the input is negated before being converted to an integer.
| Ordinarily, the fixed-point input is simply rounded to an integer, with
| the inexact exception raised if the input cannot be represented exactly as
| an integer.  However, if the fixed-point input is too large, the invalid
| exception is raised and the largest positive or negative integer is
| returned.
*----------------------------------------------------------------------------*/

2063
static int64_t roundAndPackInt64(flag zSign, uint64_t absZ0, uint64_t absZ1,
2064
                               float_status *status)
B
bellard 已提交
2065
{
2066
    int8_t roundingMode;
B
bellard 已提交
2067
    flag roundNearestEven, increment;
2068
    int64_t z;
B
bellard 已提交
2069

2070
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2071
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2072 2073
    switch (roundingMode) {
    case float_round_nearest_even:
2074
    case float_round_ties_away:
2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087
        increment = ((int64_t) absZ1 < 0);
        break;
    case float_round_to_zero:
        increment = 0;
        break;
    case float_round_up:
        increment = !zSign && absZ1;
        break;
    case float_round_down:
        increment = zSign && absZ1;
        break;
    default:
        abort();
B
bellard 已提交
2088 2089 2090 2091
    }
    if ( increment ) {
        ++absZ0;
        if ( absZ0 == 0 ) goto overflow;
2092
        absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven );
B
bellard 已提交
2093 2094 2095 2096 2097
    }
    z = absZ0;
    if ( zSign ) z = - z;
    if ( z && ( ( z < 0 ) ^ zSign ) ) {
 overflow:
P
Peter Maydell 已提交
2098
        float_raise(float_flag_invalid, status);
B
bellard 已提交
2099
        return
2100
              zSign ? (int64_t) LIT64( 0x8000000000000000 )
B
bellard 已提交
2101 2102
            : LIT64( 0x7FFFFFFFFFFFFFFF );
    }
2103 2104 2105
    if (absZ1) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2106 2107 2108 2109
    return z;

}

T
Tom Musta 已提交
2110 2111 2112 2113 2114 2115 2116 2117 2118 2119
/*----------------------------------------------------------------------------
| Takes the 128-bit fixed-point value formed by concatenating `absZ0' and
| `absZ1', with binary point between bits 63 and 64 (between the input words),
| and returns the properly rounded 64-bit unsigned integer corresponding to the
| input.  Ordinarily, the fixed-point input is simply rounded to an integer,
| with the inexact exception raised if the input cannot be represented exactly
| as an integer.  However, if the fixed-point input is too large, the invalid
| exception is raised and the largest unsigned integer is returned.
*----------------------------------------------------------------------------*/

2120
static int64_t roundAndPackUint64(flag zSign, uint64_t absZ0,
2121
                                uint64_t absZ1, float_status *status)
T
Tom Musta 已提交
2122
{
2123
    int8_t roundingMode;
T
Tom Musta 已提交
2124 2125
    flag roundNearestEven, increment;

2126
    roundingMode = status->float_rounding_mode;
T
Tom Musta 已提交
2127
    roundNearestEven = (roundingMode == float_round_nearest_even);
2128 2129
    switch (roundingMode) {
    case float_round_nearest_even:
2130
    case float_round_ties_away:
2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143
        increment = ((int64_t)absZ1 < 0);
        break;
    case float_round_to_zero:
        increment = 0;
        break;
    case float_round_up:
        increment = !zSign && absZ1;
        break;
    case float_round_down:
        increment = zSign && absZ1;
        break;
    default:
        abort();
T
Tom Musta 已提交
2144 2145 2146 2147
    }
    if (increment) {
        ++absZ0;
        if (absZ0 == 0) {
P
Peter Maydell 已提交
2148
            float_raise(float_flag_invalid, status);
T
Tom Musta 已提交
2149 2150 2151 2152 2153 2154
            return LIT64(0xFFFFFFFFFFFFFFFF);
        }
        absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven);
    }

    if (zSign && absZ0) {
P
Peter Maydell 已提交
2155
        float_raise(float_flag_invalid, status);
T
Tom Musta 已提交
2156 2157 2158 2159
        return 0;
    }

    if (absZ1) {
2160
        status->float_exception_flags |= float_flag_inexact;
T
Tom Musta 已提交
2161 2162 2163 2164
    }
    return absZ0;
}

2165 2166 2167 2168
/*----------------------------------------------------------------------------
| If `a' is denormal and we are in flush-to-zero mode then set the
| input-denormal exception and return zero. Otherwise just return the value.
*----------------------------------------------------------------------------*/
2169
float32 float32_squash_input_denormal(float32 a, float_status *status)
2170
{
2171
    if (status->flush_inputs_to_zero) {
2172
        if (extractFloat32Exp(a) == 0 && extractFloat32Frac(a) != 0) {
P
Peter Maydell 已提交
2173
            float_raise(float_flag_input_denormal, status);
2174 2175 2176 2177 2178 2179
            return make_float32(float32_val(a) & 0x80000000);
        }
    }
    return a;
}

B
bellard 已提交
2180 2181 2182 2183 2184 2185 2186 2187
/*----------------------------------------------------------------------------
| Normalizes the subnormal single-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
2188
 normalizeFloat32Subnormal(uint32_t aSig, int *zExpPtr, uint32_t *zSigPtr)
B
bellard 已提交
2189
{
2190
    int8_t shiftCount;
B
bellard 已提交
2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219

    shiftCount = countLeadingZeros32( aSig ) - 8;
    *zSigPtr = aSig<<shiftCount;
    *zExpPtr = 1 - shiftCount;

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand `zSig', and returns the proper single-precision floating-
| point value corresponding to the abstract input.  Ordinarily, the abstract
| value is simply rounded and packed into the single-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 single-
| precision floating-point number.
|     The input significand `zSig' has its binary point between bits 30
| and 29, which is 7 bits to the left of the usual location.  This shifted
| significand must be normalized or smaller.  If `zSig' 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 `zSig' 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.
*----------------------------------------------------------------------------*/

2220
static float32 roundAndPackFloat32(flag zSign, int zExp, uint32_t zSig,
2221
                                   float_status *status)
B
bellard 已提交
2222
{
2223
    int8_t roundingMode;
B
bellard 已提交
2224
    flag roundNearestEven;
2225
    int8_t roundIncrement, roundBits;
B
bellard 已提交
2226 2227
    flag isTiny;

2228
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2229
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2230 2231
    switch (roundingMode) {
    case float_round_nearest_even:
2232
    case float_round_ties_away:
2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246
        roundIncrement = 0x40;
        break;
    case float_round_to_zero:
        roundIncrement = 0;
        break;
    case float_round_up:
        roundIncrement = zSign ? 0 : 0x7f;
        break;
    case float_round_down:
        roundIncrement = zSign ? 0x7f : 0;
        break;
    default:
        abort();
        break;
B
bellard 已提交
2247 2248
    }
    roundBits = zSig & 0x7F;
2249
    if ( 0xFD <= (uint16_t) zExp ) {
B
bellard 已提交
2250 2251
        if (    ( 0xFD < zExp )
             || (    ( zExp == 0xFD )
2252
                  && ( (int32_t) ( zSig + roundIncrement ) < 0 ) )
B
bellard 已提交
2253
           ) {
P
Peter Maydell 已提交
2254
            float_raise(float_flag_overflow | float_flag_inexact, status);
P
pbrook 已提交
2255
            return packFloat32( zSign, 0xFF, - ( roundIncrement == 0 ));
B
bellard 已提交
2256 2257
        }
        if ( zExp < 0 ) {
2258
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2259
                float_raise(float_flag_output_denormal, status);
2260 2261
                return packFloat32(zSign, 0, 0);
            }
B
bellard 已提交
2262
            isTiny =
2263 2264
                (status->float_detect_tininess
                 == float_tininess_before_rounding)
B
bellard 已提交
2265 2266 2267 2268 2269
                || ( zExp < -1 )
                || ( zSig + roundIncrement < 0x80000000 );
            shift32RightJamming( zSig, - zExp, &zSig );
            zExp = 0;
            roundBits = zSig & 0x7F;
P
Peter Maydell 已提交
2270 2271 2272
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
B
bellard 已提交
2273 2274
        }
    }
2275 2276 2277
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
    zSig = ( zSig + roundIncrement )>>7;
    zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven );
    if ( zSig == 0 ) zExp = 0;
    return packFloat32( zSign, zExp, zSig );

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand `zSig', and returns the proper single-precision floating-
| point value corresponding to the abstract input.  This routine is just like
| `roundAndPackFloat32' except that `zSig' does not have to be normalized.
| Bit 31 of `zSig' must be zero, and `zExp' must be 1 less than the ``true''
| floating-point exponent.
*----------------------------------------------------------------------------*/

static float32
2295
 normalizeRoundAndPackFloat32(flag zSign, int zExp, uint32_t zSig,
2296
                              float_status *status)
B
bellard 已提交
2297
{
2298
    int8_t shiftCount;
B
bellard 已提交
2299 2300

    shiftCount = countLeadingZeros32( zSig ) - 1;
P
Peter Maydell 已提交
2301 2302
    return roundAndPackFloat32(zSign, zExp - shiftCount, zSig<<shiftCount,
                               status);
B
bellard 已提交
2303 2304 2305

}

2306 2307 2308 2309
/*----------------------------------------------------------------------------
| If `a' is denormal and we are in flush-to-zero mode then set the
| input-denormal exception and return zero. Otherwise just return the value.
*----------------------------------------------------------------------------*/
2310
float64 float64_squash_input_denormal(float64 a, float_status *status)
2311
{
2312
    if (status->flush_inputs_to_zero) {
2313
        if (extractFloat64Exp(a) == 0 && extractFloat64Frac(a) != 0) {
P
Peter Maydell 已提交
2314
            float_raise(float_flag_input_denormal, status);
2315 2316 2317 2318 2319 2320
            return make_float64(float64_val(a) & (1ULL << 63));
        }
    }
    return a;
}

B
bellard 已提交
2321 2322 2323 2324 2325 2326 2327 2328
/*----------------------------------------------------------------------------
| Normalizes the subnormal 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
2329
 normalizeFloat64Subnormal(uint64_t aSig, int *zExpPtr, uint64_t *zSigPtr)
B
bellard 已提交
2330
{
2331
    int8_t shiftCount;
B
bellard 已提交
2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349

    shiftCount = countLeadingZeros64( aSig ) - 11;
    *zSigPtr = aSig<<shiftCount;
    *zExpPtr = 1 - shiftCount;

}

/*----------------------------------------------------------------------------
| Packs the sign `zSign', exponent `zExp', and significand `zSig' into a
| double-precision floating-point value, returning the result.  After being
| shifted into the proper positions, the three fields are simply added
| together to form the result.  This means that any integer portion of `zSig'
| 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 `zSig' is a complete, normalized
| significand.
*----------------------------------------------------------------------------*/

2350
static inline float64 packFloat64(flag zSign, int zExp, uint64_t zSig)
B
bellard 已提交
2351 2352
{

P
pbrook 已提交
2353
    return make_float64(
2354
        ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<52 ) + zSig);
B
bellard 已提交
2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand `zSig', and returns the proper double-precision floating-
| point value corresponding to the abstract input.  Ordinarily, the abstract
| value is simply rounded and packed into the 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
2366 2367 2368
| 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 double-
B
bellard 已提交
2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379
| precision floating-point number.
|     The input significand `zSig' has its binary point between bits 62
| and 61, which is 10 bits to the left of the usual location.  This shifted
| significand must be normalized or smaller.  If `zSig' 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 `zSig' 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.
*----------------------------------------------------------------------------*/

2380
static float64 roundAndPackFloat64(flag zSign, int zExp, uint64_t zSig,
2381
                                   float_status *status)
B
bellard 已提交
2382
{
2383
    int8_t roundingMode;
B
bellard 已提交
2384
    flag roundNearestEven;
2385
    int roundIncrement, roundBits;
B
bellard 已提交
2386 2387
    flag isTiny;

2388
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2389
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2390 2391
    switch (roundingMode) {
    case float_round_nearest_even:
2392
    case float_round_ties_away:
2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403
        roundIncrement = 0x200;
        break;
    case float_round_to_zero:
        roundIncrement = 0;
        break;
    case float_round_up:
        roundIncrement = zSign ? 0 : 0x3ff;
        break;
    case float_round_down:
        roundIncrement = zSign ? 0x3ff : 0;
        break;
2404 2405 2406
    case float_round_to_odd:
        roundIncrement = (zSig & 0x400) ? 0 : 0x3ff;
        break;
2407 2408
    default:
        abort();
B
bellard 已提交
2409 2410
    }
    roundBits = zSig & 0x3FF;
2411
    if ( 0x7FD <= (uint16_t) zExp ) {
B
bellard 已提交
2412 2413
        if (    ( 0x7FD < zExp )
             || (    ( zExp == 0x7FD )
2414
                  && ( (int64_t) ( zSig + roundIncrement ) < 0 ) )
B
bellard 已提交
2415
           ) {
2416 2417
            bool overflow_to_inf = roundingMode != float_round_to_odd &&
                                   roundIncrement != 0;
P
Peter Maydell 已提交
2418
            float_raise(float_flag_overflow | float_flag_inexact, status);
2419
            return packFloat64(zSign, 0x7FF, -(!overflow_to_inf));
B
bellard 已提交
2420 2421
        }
        if ( zExp < 0 ) {
2422
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2423
                float_raise(float_flag_output_denormal, status);
2424 2425
                return packFloat64(zSign, 0, 0);
            }
B
bellard 已提交
2426
            isTiny =
2427 2428
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2429 2430 2431 2432 2433
                || ( zExp < -1 )
                || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) );
            shift64RightJamming( zSig, - zExp, &zSig );
            zExp = 0;
            roundBits = zSig & 0x3FF;
P
Peter Maydell 已提交
2434 2435 2436
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
2437 2438 2439 2440 2441 2442 2443
            if (roundingMode == float_round_to_odd) {
                /*
                 * For round-to-odd case, the roundIncrement depends on
                 * zSig which just changed.
                 */
                roundIncrement = (zSig & 0x400) ? 0 : 0x3ff;
            }
B
bellard 已提交
2444 2445
        }
    }
2446 2447 2448
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465
    zSig = ( zSig + roundIncrement )>>10;
    zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven );
    if ( zSig == 0 ) zExp = 0;
    return packFloat64( zSign, zExp, zSig );

}

/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand `zSig', and returns the proper double-precision floating-
| point value corresponding to the abstract input.  This routine is just like
| `roundAndPackFloat64' except that `zSig' does not have to be normalized.
| Bit 63 of `zSig' must be zero, and `zExp' must be 1 less than the ``true''
| floating-point exponent.
*----------------------------------------------------------------------------*/

static float64
2466
 normalizeRoundAndPackFloat64(flag zSign, int zExp, uint64_t zSig,
2467
                              float_status *status)
B
bellard 已提交
2468
{
2469
    int8_t shiftCount;
B
bellard 已提交
2470 2471

    shiftCount = countLeadingZeros64( zSig ) - 1;
P
Peter Maydell 已提交
2472 2473
    return roundAndPackFloat64(zSign, zExp - shiftCount, zSig<<shiftCount,
                               status);
B
bellard 已提交
2474 2475 2476 2477 2478 2479 2480 2481 2482 2483

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

2484 2485
void normalizeFloatx80Subnormal(uint64_t aSig, int32_t *zExpPtr,
                                uint64_t *zSigPtr)
B
bellard 已提交
2486
{
2487
    int8_t shiftCount;
B
bellard 已提交
2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517

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

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

2518 2519 2520
floatx80 roundAndPackFloatx80(int8_t roundingPrecision, flag zSign,
                              int32_t zExp, uint64_t zSig0, uint64_t zSig1,
                              float_status *status)
B
bellard 已提交
2521
{
2522
    int8_t roundingMode;
B
bellard 已提交
2523
    flag roundNearestEven, increment, isTiny;
2524
    int64_t roundIncrement, roundMask, roundBits;
B
bellard 已提交
2525

2526
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540
    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 );
2541 2542
    switch (roundingMode) {
    case float_round_nearest_even:
2543
    case float_round_ties_away:
2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555
        break;
    case float_round_to_zero:
        roundIncrement = 0;
        break;
    case float_round_up:
        roundIncrement = zSign ? 0 : roundMask;
        break;
    case float_round_down:
        roundIncrement = zSign ? roundMask : 0;
        break;
    default:
        abort();
B
bellard 已提交
2556 2557
    }
    roundBits = zSig0 & roundMask;
2558
    if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) {
B
bellard 已提交
2559 2560 2561 2562 2563 2564
        if (    ( 0x7FFE < zExp )
             || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) )
           ) {
            goto overflow;
        }
        if ( zExp <= 0 ) {
2565
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2566
                float_raise(float_flag_output_denormal, status);
2567 2568
                return packFloatx80(zSign, 0, 0);
            }
B
bellard 已提交
2569
            isTiny =
2570 2571
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2572 2573 2574 2575 2576
                || ( zExp < 0 )
                || ( zSig0 <= zSig0 + roundIncrement );
            shift64RightJamming( zSig0, 1 - zExp, &zSig0 );
            zExp = 0;
            roundBits = zSig0 & roundMask;
P
Peter Maydell 已提交
2577 2578 2579
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
2580 2581 2582
            if (roundBits) {
                status->float_exception_flags |= float_flag_inexact;
            }
B
bellard 已提交
2583
            zSig0 += roundIncrement;
2584
            if ( (int64_t) zSig0 < 0 ) zExp = 1;
B
bellard 已提交
2585 2586 2587 2588 2589 2590 2591 2592
            roundIncrement = roundMask + 1;
            if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
                roundMask |= roundIncrement;
            }
            zSig0 &= ~ roundMask;
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
2593 2594 2595
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608
    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:
2609 2610
    switch (roundingMode) {
    case float_round_nearest_even:
2611
    case float_round_ties_away:
2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624
        increment = ((int64_t)zSig1 < 0);
        break;
    case float_round_to_zero:
        increment = 0;
        break;
    case float_round_up:
        increment = !zSign && zSig1;
        break;
    case float_round_down:
        increment = zSign && zSig1;
        break;
    default:
        abort();
B
bellard 已提交
2625
    }
2626
    if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) {
B
bellard 已提交
2627 2628 2629 2630 2631 2632 2633 2634
        if (    ( 0x7FFE < zExp )
             || (    ( zExp == 0x7FFE )
                  && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) )
                  && increment
                )
           ) {
            roundMask = 0;
 overflow:
P
Peter Maydell 已提交
2635
            float_raise(float_flag_overflow | float_flag_inexact, status);
B
bellard 已提交
2636 2637 2638 2639 2640 2641
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
               ) {
                return packFloatx80( zSign, 0x7FFE, ~ roundMask );
            }
2642 2643 2644
            return packFloatx80(zSign,
                                floatx80_infinity_high,
                                floatx80_infinity_low);
B
bellard 已提交
2645 2646 2647
        }
        if ( zExp <= 0 ) {
            isTiny =
2648 2649
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2650 2651 2652 2653 2654
                || ( zExp < 0 )
                || ! increment
                || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) );
            shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 );
            zExp = 0;
P
Peter Maydell 已提交
2655 2656 2657
            if (isTiny && zSig1) {
                float_raise(float_flag_underflow, status);
            }
2658 2659 2660
            if (zSig1) {
                status->float_exception_flags |= float_flag_inexact;
            }
2661 2662
            switch (roundingMode) {
            case float_round_nearest_even:
2663
            case float_round_ties_away:
2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676
                increment = ((int64_t)zSig1 < 0);
                break;
            case float_round_to_zero:
                increment = 0;
                break;
            case float_round_up:
                increment = !zSign && zSig1;
                break;
            case float_round_down:
                increment = zSign && zSig1;
                break;
            default:
                abort();
B
bellard 已提交
2677 2678 2679 2680
            }
            if ( increment ) {
                ++zSig0;
                zSig0 &=
2681 2682
                    ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven );
                if ( (int64_t) zSig0 < 0 ) zExp = 1;
B
bellard 已提交
2683 2684 2685 2686
            }
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
2687 2688 2689
    if (zSig1) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2690 2691 2692 2693 2694 2695 2696
    if ( increment ) {
        ++zSig0;
        if ( zSig0 == 0 ) {
            ++zExp;
            zSig0 = LIT64( 0x8000000000000000 );
        }
        else {
2697
            zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven );
B
bellard 已提交
2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715
        }
    }
    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.
*----------------------------------------------------------------------------*/

2716 2717 2718 2719
floatx80 normalizeRoundAndPackFloatx80(int8_t roundingPrecision,
                                       flag zSign, int32_t zExp,
                                       uint64_t zSig0, uint64_t zSig1,
                                       float_status *status)
B
bellard 已提交
2720
{
2721
    int8_t shiftCount;
B
bellard 已提交
2722 2723 2724 2725 2726 2727 2728 2729 2730

    if ( zSig0 == 0 ) {
        zSig0 = zSig1;
        zSig1 = 0;
        zExp -= 64;
    }
    shiftCount = countLeadingZeros64( zSig0 );
    shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 );
    zExp -= shiftCount;
P
Peter Maydell 已提交
2731 2732
    return roundAndPackFloatx80(roundingPrecision, zSign, zExp,
                                zSig0, zSig1, status);
B
bellard 已提交
2733 2734 2735 2736 2737 2738 2739 2740

}

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

2741
static inline uint64_t extractFloat128Frac1( float128 a )
B
bellard 已提交
2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752
{

    return a.low;

}

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

2753
static inline uint64_t extractFloat128Frac0( float128 a )
B
bellard 已提交
2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764
{

    return a.high & LIT64( 0x0000FFFFFFFFFFFF );

}

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

2765
static inline int32_t extractFloat128Exp( float128 a )
B
bellard 已提交
2766 2767 2768 2769 2770 2771 2772 2773 2774 2775
{

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

}

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

2776
static inline flag extractFloat128Sign( float128 a )
B
bellard 已提交
2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794
{

    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(
2795 2796
     uint64_t aSig0,
     uint64_t aSig1,
2797
     int32_t *zExpPtr,
2798 2799
     uint64_t *zSig0Ptr,
     uint64_t *zSig1Ptr
B
bellard 已提交
2800 2801
 )
{
2802
    int8_t shiftCount;
B
bellard 已提交
2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836

    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.
*----------------------------------------------------------------------------*/

2837
static inline float128
2838
 packFloat128( flag zSign, int32_t zExp, uint64_t zSig0, uint64_t zSig1 )
B
bellard 已提交
2839 2840 2841 2842
{
    float128 z;

    z.low = zSig1;
2843
    z.high = ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<48 ) + zSig0;
B
bellard 已提交
2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
    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.
*----------------------------------------------------------------------------*/

2869
static float128 roundAndPackFloat128(flag zSign, int32_t zExp,
2870 2871
                                     uint64_t zSig0, uint64_t zSig1,
                                     uint64_t zSig2, float_status *status)
B
bellard 已提交
2872
{
2873
    int8_t roundingMode;
B
bellard 已提交
2874 2875
    flag roundNearestEven, increment, isTiny;

2876
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2877
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2878 2879
    switch (roundingMode) {
    case float_round_nearest_even:
2880
    case float_round_ties_away:
2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891
        increment = ((int64_t)zSig2 < 0);
        break;
    case float_round_to_zero:
        increment = 0;
        break;
    case float_round_up:
        increment = !zSign && zSig2;
        break;
    case float_round_down:
        increment = zSign && zSig2;
        break;
2892 2893 2894
    case float_round_to_odd:
        increment = !(zSig1 & 0x1) && zSig2;
        break;
2895 2896
    default:
        abort();
B
bellard 已提交
2897
    }
2898
    if ( 0x7FFD <= (uint32_t) zExp ) {
B
bellard 已提交
2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909
        if (    ( 0x7FFD < zExp )
             || (    ( zExp == 0x7FFD )
                  && eq128(
                         LIT64( 0x0001FFFFFFFFFFFF ),
                         LIT64( 0xFFFFFFFFFFFFFFFF ),
                         zSig0,
                         zSig1
                     )
                  && increment
                )
           ) {
P
Peter Maydell 已提交
2910
            float_raise(float_flag_overflow | float_flag_inexact, status);
B
bellard 已提交
2911 2912 2913
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
2914
                 || (roundingMode == float_round_to_odd)
B
bellard 已提交
2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926
               ) {
                return
                    packFloat128(
                        zSign,
                        0x7FFE,
                        LIT64( 0x0000FFFFFFFFFFFF ),
                        LIT64( 0xFFFFFFFFFFFFFFFF )
                    );
            }
            return packFloat128( zSign, 0x7FFF, 0, 0 );
        }
        if ( zExp < 0 ) {
2927
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2928
                float_raise(float_flag_output_denormal, status);
2929 2930
                return packFloat128(zSign, 0, 0, 0);
            }
B
bellard 已提交
2931
            isTiny =
2932 2933
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944
                || ( zExp < -1 )
                || ! increment
                || lt128(
                       zSig0,
                       zSig1,
                       LIT64( 0x0001FFFFFFFFFFFF ),
                       LIT64( 0xFFFFFFFFFFFFFFFF )
                   );
            shift128ExtraRightJamming(
                zSig0, zSig1, zSig2, - zExp, &zSig0, &zSig1, &zSig2 );
            zExp = 0;
P
Peter Maydell 已提交
2945 2946 2947
            if (isTiny && zSig2) {
                float_raise(float_flag_underflow, status);
            }
2948 2949
            switch (roundingMode) {
            case float_round_nearest_even:
2950
            case float_round_ties_away:
2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961
                increment = ((int64_t)zSig2 < 0);
                break;
            case float_round_to_zero:
                increment = 0;
                break;
            case float_round_up:
                increment = !zSign && zSig2;
                break;
            case float_round_down:
                increment = zSign && zSig2;
                break;
2962 2963 2964
            case float_round_to_odd:
                increment = !(zSig1 & 0x1) && zSig2;
                break;
2965 2966
            default:
                abort();
B
bellard 已提交
2967 2968 2969
            }
        }
    }
2970 2971 2972
    if (zSig2) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993
    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.
*----------------------------------------------------------------------------*/

2994
static float128 normalizeRoundAndPackFloat128(flag zSign, int32_t zExp,
2995 2996
                                              uint64_t zSig0, uint64_t zSig1,
                                              float_status *status)
B
bellard 已提交
2997
{
2998
    int8_t shiftCount;
2999
    uint64_t zSig2;
B
bellard 已提交
3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015

    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;
P
Peter Maydell 已提交
3016
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027

}


/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3028
floatx80 int32_to_floatx80(int32_t a, float_status *status)
B
bellard 已提交
3029 3030
{
    flag zSign;
3031
    uint32_t absA;
3032
    int8_t shiftCount;
3033
    uint64_t zSig;
B
bellard 已提交
3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049

    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 );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3050
float128 int32_to_float128(int32_t a, float_status *status)
B
bellard 已提交
3051 3052
{
    flag zSign;
3053
    uint32_t absA;
3054
    int8_t shiftCount;
3055
    uint64_t zSig0;
B
bellard 已提交
3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072

    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 );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3073
floatx80 int64_to_floatx80(int64_t a, float_status *status)
B
bellard 已提交
3074 3075
{
    flag zSign;
3076
    uint64_t absA;
3077
    int8_t shiftCount;
B
bellard 已提交
3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092

    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 );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3093
float128 int64_to_float128(int64_t a, float_status *status)
B
bellard 已提交
3094 3095
{
    flag zSign;
3096
    uint64_t absA;
3097
    int8_t shiftCount;
3098
    int32_t zExp;
3099
    uint64_t zSig0, zSig1;
B
bellard 已提交
3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119

    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 );

}

3120 3121 3122 3123 3124 3125
/*----------------------------------------------------------------------------
| Returns the result of converting the 64-bit unsigned integer `a'
| to the quadruple-precision floating-point format.  The conversion is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

3126
float128 uint64_to_float128(uint64_t a, float_status *status)
3127 3128 3129 3130
{
    if (a == 0) {
        return float128_zero;
    }
3131
    return normalizeRoundAndPackFloat128(0, 0x406E, 0, a, status);
3132 3133
}

B
bellard 已提交
3134 3135 3136 3137 3138 3139 3140 3141 3142 3143



/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3144
float64 float32_to_float64(float32 a, float_status *status)
B
bellard 已提交
3145 3146
{
    flag aSign;
3147
    int aExp;
3148
    uint32_t aSig;
P
Peter Maydell 已提交
3149
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3150 3151 3152 3153 3154

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3155 3156 3157
        if (aSig) {
            return commonNaNToFloat64(float32ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3158 3159 3160 3161 3162 3163 3164
        return packFloat64( aSign, 0x7FF, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat64( aSign, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
3165
    return packFloat64( aSign, aExp + 0x380, ( (uint64_t) aSig )<<29 );
B
bellard 已提交
3166 3167 3168 3169 3170 3171 3172 3173 3174 3175

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3176
floatx80 float32_to_floatx80(float32 a, float_status *status)
B
bellard 已提交
3177 3178
{
    flag aSign;
3179
    int aExp;
3180
    uint32_t aSig;
B
bellard 已提交
3181

P
Peter Maydell 已提交
3182
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3183 3184 3185 3186
    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3187 3188 3189
        if (aSig) {
            return commonNaNToFloatx80(float32ToCommonNaN(a, status), status);
        }
3190 3191 3192
        return packFloatx80(aSign,
                            floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
3193 3194 3195 3196 3197 3198
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
    }
    aSig |= 0x00800000;
3199
    return packFloatx80( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<40 );
B
bellard 已提交
3200 3201 3202 3203 3204 3205 3206 3207 3208 3209

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3210
float128 float32_to_float128(float32 a, float_status *status)
B
bellard 已提交
3211 3212
{
    flag aSign;
3213
    int aExp;
3214
    uint32_t aSig;
B
bellard 已提交
3215

P
Peter Maydell 已提交
3216
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3217 3218 3219 3220
    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3221 3222 3223
        if (aSig) {
            return commonNaNToFloat128(float32ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3224 3225 3226 3227 3228 3229 3230
        return packFloat128( aSign, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
3231
    return packFloat128( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<25, 0 );
B
bellard 已提交
3232 3233 3234 3235 3236 3237 3238 3239 3240

}

/*----------------------------------------------------------------------------
| Returns the remainder of the single-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.
*----------------------------------------------------------------------------*/

3241
float32 float32_rem(float32 a, float32 b, float_status *status)
B
bellard 已提交
3242
{
3243
    flag aSign, zSign;
3244
    int aExp, bExp, expDiff;
3245 3246 3247 3248 3249
    uint32_t aSig, bSig;
    uint32_t q;
    uint64_t aSig64, bSig64, q64;
    uint32_t alternateASig;
    int32_t sigMean;
P
Peter Maydell 已提交
3250 3251
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3252 3253 3254 3255 3256 3257 3258 3259

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    bSig = extractFloat32Frac( b );
    bExp = extractFloat32Exp( b );
    if ( aExp == 0xFF ) {
        if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) {
P
Peter Maydell 已提交
3260
            return propagateFloat32NaN(a, b, status);
B
bellard 已提交
3261
        }
P
Peter Maydell 已提交
3262
        float_raise(float_flag_invalid, status);
3263
        return float32_default_nan(status);
B
bellard 已提交
3264 3265
    }
    if ( bExp == 0xFF ) {
P
Peter Maydell 已提交
3266 3267 3268
        if (bSig) {
            return propagateFloat32NaN(a, b, status);
        }
B
bellard 已提交
3269 3270 3271 3272
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
P
Peter Maydell 已提交
3273
            float_raise(float_flag_invalid, status);
3274
            return float32_default_nan(status);
B
bellard 已提交
3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294
        }
        normalizeFloat32Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return a;
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
    }
    expDiff = aExp - bExp;
    aSig |= 0x00800000;
    bSig |= 0x00800000;
    if ( expDiff < 32 ) {
        aSig <<= 8;
        bSig <<= 8;
        if ( expDiff < 0 ) {
            if ( expDiff < -1 ) return a;
            aSig >>= 1;
        }
        q = ( bSig <= aSig );
        if ( q ) aSig -= bSig;
        if ( 0 < expDiff ) {
3295
            q = ( ( (uint64_t) aSig )<<32 ) / bSig;
B
bellard 已提交
3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306
            q >>= 32 - expDiff;
            bSig >>= 2;
            aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q;
        }
        else {
            aSig >>= 2;
            bSig >>= 2;
        }
    }
    else {
        if ( bSig <= aSig ) aSig -= bSig;
3307 3308
        aSig64 = ( (uint64_t) aSig )<<40;
        bSig64 = ( (uint64_t) bSig )<<40;
B
bellard 已提交
3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326
        expDiff -= 64;
        while ( 0 < expDiff ) {
            q64 = estimateDiv128To64( aSig64, 0, bSig64 );
            q64 = ( 2 < q64 ) ? q64 - 2 : 0;
            aSig64 = - ( ( bSig * q64 )<<38 );
            expDiff -= 62;
        }
        expDiff += 64;
        q64 = estimateDiv128To64( aSig64, 0, bSig64 );
        q64 = ( 2 < q64 ) ? q64 - 2 : 0;
        q = q64>>( 64 - expDiff );
        bSig <<= 6;
        aSig = ( ( aSig64>>33 )<<( expDiff - 1 ) ) - bSig * q;
    }
    do {
        alternateASig = aSig;
        ++q;
        aSig -= bSig;
3327
    } while ( 0 <= (int32_t) aSig );
B
bellard 已提交
3328 3329 3330 3331
    sigMean = aSig + alternateASig;
    if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
        aSig = alternateASig;
    }
3332
    zSign = ( (int32_t) aSig < 0 );
B
bellard 已提交
3333
    if ( zSign ) aSig = - aSig;
P
Peter Maydell 已提交
3334
    return normalizeRoundAndPackFloat32(aSign ^ zSign, bExp, aSig, status);
B
bellard 已提交
3335 3336
}

3337

B
bellard 已提交
3338

A
Aurelien Jarno 已提交
3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358
/*----------------------------------------------------------------------------
| Returns the binary exponential of the single-precision floating-point value
| `a'. The operation is performed according to the IEC/IEEE Standard for
| Binary Floating-Point Arithmetic.
|
| Uses the following identities:
|
| 1. -------------------------------------------------------------------------
|      x    x*ln(2)
|     2  = e
|
| 2. -------------------------------------------------------------------------
|                      2     3     4     5           n
|      x        x     x     x     x     x           x
|     e  = 1 + --- + --- + --- + --- + --- + ... + --- + ...
|               1!    2!    3!    4!    5!          n!
*----------------------------------------------------------------------------*/

static const float64 float32_exp2_coefficients[15] =
{
3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373
    const_float64( 0x3ff0000000000000ll ), /*  1 */
    const_float64( 0x3fe0000000000000ll ), /*  2 */
    const_float64( 0x3fc5555555555555ll ), /*  3 */
    const_float64( 0x3fa5555555555555ll ), /*  4 */
    const_float64( 0x3f81111111111111ll ), /*  5 */
    const_float64( 0x3f56c16c16c16c17ll ), /*  6 */
    const_float64( 0x3f2a01a01a01a01all ), /*  7 */
    const_float64( 0x3efa01a01a01a01all ), /*  8 */
    const_float64( 0x3ec71de3a556c734ll ), /*  9 */
    const_float64( 0x3e927e4fb7789f5cll ), /* 10 */
    const_float64( 0x3e5ae64567f544e4ll ), /* 11 */
    const_float64( 0x3e21eed8eff8d898ll ), /* 12 */
    const_float64( 0x3de6124613a86d09ll ), /* 13 */
    const_float64( 0x3da93974a8c07c9dll ), /* 14 */
    const_float64( 0x3d6ae7f3e733b81fll ), /* 15 */
A
Aurelien Jarno 已提交
3374 3375
};

3376
float32 float32_exp2(float32 a, float_status *status)
A
Aurelien Jarno 已提交
3377 3378
{
    flag aSign;
3379
    int aExp;
3380
    uint32_t aSig;
A
Aurelien Jarno 已提交
3381 3382
    float64 r, x, xn;
    int i;
P
Peter Maydell 已提交
3383
    a = float32_squash_input_denormal(a, status);
A
Aurelien Jarno 已提交
3384 3385 3386 3387 3388 3389

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );

    if ( aExp == 0xFF) {
P
Peter Maydell 已提交
3390 3391 3392
        if (aSig) {
            return propagateFloat32NaN(a, float32_zero, status);
        }
A
Aurelien Jarno 已提交
3393 3394 3395 3396 3397 3398
        return (aSign) ? float32_zero : a;
    }
    if (aExp == 0) {
        if (aSig == 0) return float32_one;
    }

P
Peter Maydell 已提交
3399
    float_raise(float_flag_inexact, status);
A
Aurelien Jarno 已提交
3400 3401 3402 3403

    /* ******************************* */
    /* using float64 for approximation */
    /* ******************************* */
P
Peter Maydell 已提交
3404 3405
    x = float32_to_float64(a, status);
    x = float64_mul(x, float64_ln2, status);
A
Aurelien Jarno 已提交
3406 3407 3408 3409 3410 3411

    xn = x;
    r = float64_one;
    for (i = 0 ; i < 15 ; i++) {
        float64 f;

P
Peter Maydell 已提交
3412 3413
        f = float64_mul(xn, float32_exp2_coefficients[i], status);
        r = float64_add(r, f, status);
A
Aurelien Jarno 已提交
3414

P
Peter Maydell 已提交
3415
        xn = float64_mul(xn, x, status);
A
Aurelien Jarno 已提交
3416 3417 3418 3419 3420
    }

    return float64_to_float32(r, status);
}

3421 3422 3423 3424 3425
/*----------------------------------------------------------------------------
| Returns the binary log of the single-precision floating-point value `a'.
| The operation is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/
3426
float32 float32_log2(float32 a, float_status *status)
3427 3428
{
    flag aSign, zSign;
3429
    int aExp;
3430
    uint32_t aSig, zSig, i;
3431

P
Peter Maydell 已提交
3432
    a = float32_squash_input_denormal(a, status);
3433 3434 3435 3436 3437 3438 3439 3440 3441
    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );

    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat32( 1, 0xFF, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
    }
    if ( aSign ) {
P
Peter Maydell 已提交
3442
        float_raise(float_flag_invalid, status);
3443
        return float32_default_nan(status);
3444 3445
    }
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3446 3447 3448
        if (aSig) {
            return propagateFloat32NaN(a, float32_zero, status);
        }
3449 3450 3451 3452 3453 3454 3455 3456 3457
        return a;
    }

    aExp -= 0x7F;
    aSig |= 0x00800000;
    zSign = aExp < 0;
    zSig = aExp << 23;

    for (i = 1 << 22; i > 0; i >>= 1) {
3458
        aSig = ( (uint64_t)aSig * aSig ) >> 23;
3459 3460 3461 3462 3463 3464 3465 3466 3467
        if ( aSig & 0x01000000 ) {
            aSig >>= 1;
            zSig |= i;
        }
    }

    if ( zSign )
        zSig = -zSig;

P
Peter Maydell 已提交
3468
    return normalizeRoundAndPackFloat32(zSign, 0x85, zSig, status);
3469 3470
}

B
bellard 已提交
3471 3472
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is equal to
3473 3474
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  Otherwise, the comparison is performed
B
bellard 已提交
3475 3476 3477
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

3478
int float32_eq(float32 a, float32 b, float_status *status)
B
bellard 已提交
3479
{
3480
    uint32_t av, bv;
P
Peter Maydell 已提交
3481 3482
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3483 3484 3485 3486

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3487
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3488 3489
        return 0;
    }
3490 3491 3492
    av = float32_val(a);
    bv = float32_val(b);
    return ( av == bv ) || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
3493 3494 3495 3496
}

/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is less than
3497 3498 3499
| or equal to the corresponding value `b', and 0 otherwise.  The invalid
| exception is raised if either operand is a NaN.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
3500 3501
*----------------------------------------------------------------------------*/

3502
int float32_le(float32 a, float32 b, float_status *status)
B
bellard 已提交
3503 3504
{
    flag aSign, bSign;
3505
    uint32_t av, bv;
P
Peter Maydell 已提交
3506 3507
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3508 3509 3510 3511

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3512
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3513 3514 3515 3516
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3517 3518
    av = float32_val(a);
    bv = float32_val(b);
3519
    if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
3520
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
3521 3522 3523 3524 3525

}

/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is less than
3526 3527 3528
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  The comparison is performed according
| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
3529 3530
*----------------------------------------------------------------------------*/

3531
int float32_lt(float32 a, float32 b, float_status *status)
B
bellard 已提交
3532 3533
{
    flag aSign, bSign;
3534
    uint32_t av, bv;
P
Peter Maydell 已提交
3535 3536
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3537 3538 3539 3540

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3541
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3542 3543 3544 3545
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3546 3547
    av = float32_val(a);
    bv = float32_val(b);
3548
    if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
3549
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
3550 3551 3552

}

3553 3554
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point values `a' and `b' cannot
3555 3556 3557
| be compared, and 0 otherwise.  The invalid exception is raised if either
| operand is a NaN.  The comparison is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
3558 3559
*----------------------------------------------------------------------------*/

3560
int float32_unordered(float32 a, float32 b, float_status *status)
3561
{
P
Peter Maydell 已提交
3562 3563
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
3564 3565 3566 3567

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3568
        float_raise(float_flag_invalid, status);
3569 3570 3571 3572
        return 1;
    }
    return 0;
}
3573

B
bellard 已提交
3574 3575
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is equal to
3576 3577 3578
| the corresponding value `b', and 0 otherwise.  Quiet NaNs do not cause an
| exception.  The comparison is performed according to the IEC/IEEE Standard
| for Binary Floating-Point Arithmetic.
B
bellard 已提交
3579 3580
*----------------------------------------------------------------------------*/

3581
int float32_eq_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3582
{
P
Peter Maydell 已提交
3583 3584
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3585 3586 3587 3588

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
3589 3590
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
3591
            float_raise(float_flag_invalid, status);
3592
        }
B
bellard 已提交
3593 3594
        return 0;
    }
3595 3596
    return ( float32_val(a) == float32_val(b) ) ||
            ( (uint32_t) ( ( float32_val(a) | float32_val(b) )<<1 ) == 0 );
B
bellard 已提交
3597 3598 3599 3600 3601 3602 3603 3604 3605
}

/*----------------------------------------------------------------------------
| Returns 1 if the single-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.
*----------------------------------------------------------------------------*/

3606
int float32_le_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3607 3608
{
    flag aSign, bSign;
3609
    uint32_t av, bv;
P
Peter Maydell 已提交
3610 3611
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3612 3613 3614 3615

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
3616 3617
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
3618
            float_raise(float_flag_invalid, status);
B
bellard 已提交
3619 3620 3621 3622 3623
        }
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3624 3625
    av = float32_val(a);
    bv = float32_val(b);
3626
    if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
3627
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
3628 3629 3630 3631 3632 3633 3634

}

/*----------------------------------------------------------------------------
| Returns 1 if the single-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
3635
| Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
3636 3637
*----------------------------------------------------------------------------*/

3638
int float32_lt_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3639
{
3640 3641 3642 3643
    flag aSign, bSign;
    uint32_t av, bv;
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3644

3645 3646 3647 3648 3649
    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
3650
            float_raise(float_flag_invalid, status);
B
bellard 已提交
3651
        }
3652
        return 0;
B
bellard 已提交
3653
    }
3654 3655 3656 3657 3658 3659
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
    av = float32_val(a);
    bv = float32_val(b);
    if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 );
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
3660 3661 3662 3663

}

/*----------------------------------------------------------------------------
3664 3665 3666 3667
| Returns 1 if the single-precision floating-point values `a' and `b' cannot
| be compared, and 0 otherwise.  Quiet NaNs do not cause an exception.  The
| comparison is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
B
bellard 已提交
3668 3669
*----------------------------------------------------------------------------*/

3670
int float32_unordered_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3671
{
3672 3673
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3674

3675 3676 3677 3678 3679 3680
    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
            float_raise(float_flag_invalid, status);
B
bellard 已提交
3681
        }
3682
        return 1;
B
bellard 已提交
3683
    }
3684
    return 0;
B
bellard 已提交
3685 3686
}

3687

B
bellard 已提交
3688 3689 3690 3691 3692 3693 3694
/*----------------------------------------------------------------------------
| Returns the result of converting the 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.
*----------------------------------------------------------------------------*/

3695
float32 float64_to_float32(float64 a, float_status *status)
B
bellard 已提交
3696 3697
{
    flag aSign;
3698
    int aExp;
3699 3700
    uint64_t aSig;
    uint32_t zSig;
P
Peter Maydell 已提交
3701
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
3702 3703 3704 3705 3706

    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
3707 3708 3709
        if (aSig) {
            return commonNaNToFloat32(float64ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3710 3711 3712 3713 3714 3715 3716 3717
        return packFloat32( aSign, 0xFF, 0 );
    }
    shift64RightJamming( aSig, 22, &aSig );
    zSig = aSig;
    if ( aExp || zSig ) {
        zSig |= 0x40000000;
        aExp -= 0x381;
    }
P
Peter Maydell 已提交
3718
    return roundAndPackFloat32(aSign, aExp, zSig, status);
B
bellard 已提交
3719 3720 3721

}

P
Paul Brook 已提交
3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732

/*----------------------------------------------------------------------------
| Packs the sign `zSign', exponent `zExp', and significand `zSig' into a
| half-precision floating-point value, returning the result.  After being
| shifted into the proper positions, the three fields are simply added
| together to form the result.  This means that any integer portion of `zSig'
| 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 `zSig' is a complete, normalized
| significand.
*----------------------------------------------------------------------------*/
3733
static float16 packFloat16(flag zSign, int zExp, uint16_t zSig)
P
Paul Brook 已提交
3734
{
3735
    return make_float16(
3736
        (((uint32_t)zSign) << 15) + (((uint32_t)zExp) << 10) + zSig);
P
Paul Brook 已提交
3737 3738
}

3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766
/*----------------------------------------------------------------------------
| Takes an abstract floating-point value having sign `zSign', exponent `zExp',
| and significand `zSig', and returns the proper half-precision floating-
| point value corresponding to the abstract input.  Ordinarily, the abstract
| value is simply rounded and packed into the half-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 half-
| precision floating-point number.
| The `ieee' flag indicates whether to use IEEE standard half precision, or
| ARM-style "alternative representation", which omits the NaN and Inf
| encodings in order to raise the maximum representable exponent by one.
|     The input significand `zSig' has its binary point between bits 22
| and 23, which is 13 bits to the left of the usual location.  This shifted
| significand must be normalized or smaller.  If `zSig' 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 `zSig' is
| normalized, `zExp' must be 1 less than the ``true'' floating-point exponent.
| Note the slightly odd position of the binary point in zSig compared with the
| other roundAndPackFloat functions. This should probably be fixed if we
| need to implement more float16 routines than just conversion.
| The handling of underflow and overflow follows the IEC/IEEE Standard for
| Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

3767
static float16 roundAndPackFloat16(flag zSign, int zExp,
3768 3769
                                   uint32_t zSig, flag ieee,
                                   float_status *status)
3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790
{
    int maxexp = ieee ? 29 : 30;
    uint32_t mask;
    uint32_t increment;
    bool rounding_bumps_exp;
    bool is_tiny = false;

    /* Calculate the mask of bits of the mantissa which are not
     * representable in half-precision and will be lost.
     */
    if (zExp < 1) {
        /* Will be denormal in halfprec */
        mask = 0x00ffffff;
        if (zExp >= -11) {
            mask >>= 11 + zExp;
        }
    } else {
        /* Normal number in halfprec */
        mask = 0x00001fff;
    }

3791
    switch (status->float_rounding_mode) {
3792 3793 3794 3795 3796 3797
    case float_round_nearest_even:
        increment = (mask + 1) >> 1;
        if ((zSig & mask) == increment) {
            increment = zSig & (increment << 1);
        }
        break;
3798 3799 3800
    case float_round_ties_away:
        increment = (mask + 1) >> 1;
        break;
3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815
    case float_round_up:
        increment = zSign ? 0 : mask;
        break;
    case float_round_down:
        increment = zSign ? mask : 0;
        break;
    default: /* round_to_zero */
        increment = 0;
        break;
    }

    rounding_bumps_exp = (zSig + increment >= 0x01000000);

    if (zExp > maxexp || (zExp == maxexp && rounding_bumps_exp)) {
        if (ieee) {
P
Peter Maydell 已提交
3816
            float_raise(float_flag_overflow | float_flag_inexact, status);
3817 3818
            return packFloat16(zSign, 0x1f, 0);
        } else {
P
Peter Maydell 已提交
3819
            float_raise(float_flag_invalid, status);
3820 3821 3822 3823 3824 3825 3826
            return packFloat16(zSign, 0x1f, 0x3ff);
        }
    }

    if (zExp < 0) {
        /* Note that flush-to-zero does not affect half-precision results */
        is_tiny =
3827
            (status->float_detect_tininess == float_tininess_before_rounding)
3828 3829 3830 3831
            || (zExp < -1)
            || (!rounding_bumps_exp);
    }
    if (zSig & mask) {
P
Peter Maydell 已提交
3832
        float_raise(float_flag_inexact, status);
3833
        if (is_tiny) {
P
Peter Maydell 已提交
3834
            float_raise(float_flag_underflow, status);
3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853
        }
    }

    zSig += increment;
    if (rounding_bumps_exp) {
        zSig >>= 1;
        zExp++;
    }

    if (zExp < -10) {
        return packFloat16(zSign, 0, 0);
    }
    if (zExp < 0) {
        zSig >>= -zExp;
        zExp = 0;
    }
    return packFloat16(zSign, zExp, zSig >> 13);
}

3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868
/*----------------------------------------------------------------------------
| If `a' is denormal and we are in flush-to-zero mode then set the
| input-denormal exception and return zero. Otherwise just return the value.
*----------------------------------------------------------------------------*/
float16 float16_squash_input_denormal(float16 a, float_status *status)
{
    if (status->flush_inputs_to_zero) {
        if (extractFloat16Exp(a) == 0 && extractFloat16Frac(a) != 0) {
            float_raise(float_flag_input_denormal, status);
            return make_float16(float16_val(a) & 0x8000);
        }
    }
    return a;
}

3869
static void normalizeFloat16Subnormal(uint32_t aSig, int *zExpPtr,
3870 3871 3872 3873 3874 3875 3876
                                      uint32_t *zSigPtr)
{
    int8_t shiftCount = countLeadingZeros32(aSig) - 21;
    *zSigPtr = aSig << shiftCount;
    *zExpPtr = 1 - shiftCount;
}

P
Paul Brook 已提交
3877 3878
/* Half precision floats come in two formats: standard IEEE and "ARM" format.
   The latter gains extra exponent range by omitting the NaN/Inf encodings.  */
3879

3880
float32 float16_to_float32(float16 a, flag ieee, float_status *status)
P
Paul Brook 已提交
3881 3882
{
    flag aSign;
3883
    int aExp;
3884
    uint32_t aSig;
P
Paul Brook 已提交
3885

3886 3887 3888
    aSign = extractFloat16Sign(a);
    aExp = extractFloat16Exp(a);
    aSig = extractFloat16Frac(a);
P
Paul Brook 已提交
3889 3890 3891

    if (aExp == 0x1f && ieee) {
        if (aSig) {
P
Peter Maydell 已提交
3892
            return commonNaNToFloat32(float16ToCommonNaN(a, status), status);
P
Paul Brook 已提交
3893
        }
3894
        return packFloat32(aSign, 0xff, 0);
P
Paul Brook 已提交
3895 3896 3897 3898 3899 3900
    }
    if (aExp == 0) {
        if (aSig == 0) {
            return packFloat32(aSign, 0, 0);
        }

3901 3902
        normalizeFloat16Subnormal(aSig, &aExp, &aSig);
        aExp--;
P
Paul Brook 已提交
3903 3904 3905 3906
    }
    return packFloat32( aSign, aExp + 0x70, aSig << 13);
}

3907
float16 float32_to_float16(float32 a, flag ieee, float_status *status)
P
Paul Brook 已提交
3908 3909
{
    flag aSign;
3910
    int aExp;
3911
    uint32_t aSig;
3912

P
Peter Maydell 已提交
3913
    a = float32_squash_input_denormal(a, status);
P
Paul Brook 已提交
3914 3915 3916 3917 3918 3919

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
        if (aSig) {
3920 3921
            /* Input is a NaN */
            if (!ieee) {
P
Peter Maydell 已提交
3922
                float_raise(float_flag_invalid, status);
3923 3924
                return packFloat16(aSign, 0, 0);
            }
3925
            return commonNaNToFloat16(
P
Peter Maydell 已提交
3926
                float32ToCommonNaN(a, status), status);
P
Paul Brook 已提交
3927
        }
3928 3929
        /* Infinity */
        if (!ieee) {
P
Peter Maydell 已提交
3930
            float_raise(float_flag_invalid, status);
3931 3932 3933
            return packFloat16(aSign, 0x1f, 0x3ff);
        }
        return packFloat16(aSign, 0x1f, 0);
P
Paul Brook 已提交
3934
    }
3935
    if (aExp == 0 && aSig == 0) {
P
Paul Brook 已提交
3936 3937
        return packFloat16(aSign, 0, 0);
    }
3938 3939 3940 3941 3942 3943 3944
    /* Decimal point between bits 22 and 23. Note that we add the 1 bit
     * even if the input is denormal; however this is harmless because
     * the largest possible single-precision denormal is still smaller
     * than the smallest representable half-precision denormal, and so we
     * will end up ignoring aSig and returning via the "always return zero"
     * codepath.
     */
P
Paul Brook 已提交
3945
    aSig |= 0x00800000;
3946
    aExp -= 0x71;
P
Paul Brook 已提交
3947

P
Peter Maydell 已提交
3948
    return roundAndPackFloat16(aSign, aExp, aSig, ieee, status);
P
Paul Brook 已提交
3949 3950
}

3951
float64 float16_to_float64(float16 a, flag ieee, float_status *status)
3952 3953
{
    flag aSign;
3954
    int aExp;
3955 3956 3957 3958 3959 3960 3961 3962 3963
    uint32_t aSig;

    aSign = extractFloat16Sign(a);
    aExp = extractFloat16Exp(a);
    aSig = extractFloat16Frac(a);

    if (aExp == 0x1f && ieee) {
        if (aSig) {
            return commonNaNToFloat64(
P
Peter Maydell 已提交
3964
                float16ToCommonNaN(a, status), status);
3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978
        }
        return packFloat64(aSign, 0x7ff, 0);
    }
    if (aExp == 0) {
        if (aSig == 0) {
            return packFloat64(aSign, 0, 0);
        }

        normalizeFloat16Subnormal(aSig, &aExp, &aSig);
        aExp--;
    }
    return packFloat64(aSign, aExp + 0x3f0, ((uint64_t)aSig) << 42);
}

3979
float16 float64_to_float16(float64 a, flag ieee, float_status *status)
3980 3981
{
    flag aSign;
3982
    int aExp;
3983 3984 3985
    uint64_t aSig;
    uint32_t zSig;

P
Peter Maydell 已提交
3986
    a = float64_squash_input_denormal(a, status);
3987 3988 3989 3990 3991 3992 3993 3994

    aSig = extractFloat64Frac(a);
    aExp = extractFloat64Exp(a);
    aSign = extractFloat64Sign(a);
    if (aExp == 0x7FF) {
        if (aSig) {
            /* Input is a NaN */
            if (!ieee) {
P
Peter Maydell 已提交
3995
                float_raise(float_flag_invalid, status);
3996 3997 3998
                return packFloat16(aSign, 0, 0);
            }
            return commonNaNToFloat16(
P
Peter Maydell 已提交
3999
                float64ToCommonNaN(a, status), status);
4000 4001 4002
        }
        /* Infinity */
        if (!ieee) {
P
Peter Maydell 已提交
4003
            float_raise(float_flag_invalid, status);
4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022
            return packFloat16(aSign, 0x1f, 0x3ff);
        }
        return packFloat16(aSign, 0x1f, 0);
    }
    shift64RightJamming(aSig, 29, &aSig);
    zSig = aSig;
    if (aExp == 0 && zSig == 0) {
        return packFloat16(aSign, 0, 0);
    }
    /* Decimal point between bits 22 and 23. Note that we add the 1 bit
     * even if the input is denormal; however this is harmless because
     * the largest possible single-precision denormal is still smaller
     * than the smallest representable half-precision denormal, and so we
     * will end up ignoring aSig and returning via the "always return zero"
     * codepath.
     */
    zSig |= 0x00800000;
    aExp -= 0x3F1;

P
Peter Maydell 已提交
4023
    return roundAndPackFloat16(aSign, aExp, zSig, ieee, status);
4024 4025
}

B
bellard 已提交
4026 4027 4028 4029 4030 4031 4032
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4033
floatx80 float64_to_floatx80(float64 a, float_status *status)
B
bellard 已提交
4034 4035
{
    flag aSign;
4036
    int aExp;
4037
    uint64_t aSig;
B
bellard 已提交
4038

P
Peter Maydell 已提交
4039
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
4040 4041 4042 4043
    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4044 4045 4046
        if (aSig) {
            return commonNaNToFloatx80(float64ToCommonNaN(a, status), status);
        }
4047 4048 4049
        return packFloatx80(aSign,
                            floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat64Subnormal( aSig, &aExp, &aSig );
    }
    return
        packFloatx80(
            aSign, aExp + 0x3C00, ( aSig | LIT64( 0x0010000000000000 ) )<<11 );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4068
float128 float64_to_float128(float64 a, float_status *status)
B
bellard 已提交
4069 4070
{
    flag aSign;
4071
    int aExp;
4072
    uint64_t aSig, zSig0, zSig1;
B
bellard 已提交
4073

P
Peter Maydell 已提交
4074
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
4075 4076 4077 4078
    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4079 4080 4081
        if (aSig) {
            return commonNaNToFloat128(float64ToCommonNaN(a, status), status);
        }
B
bellard 已提交
4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100
        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 );

}


/*----------------------------------------------------------------------------
| Returns the remainder of the 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.
*----------------------------------------------------------------------------*/

4101
float64 float64_rem(float64 a, float64 b, float_status *status)
B
bellard 已提交
4102
{
4103
    flag aSign, zSign;
4104
    int aExp, bExp, expDiff;
4105 4106 4107
    uint64_t aSig, bSig;
    uint64_t q, alternateASig;
    int64_t sigMean;
B
bellard 已提交
4108

P
Peter Maydell 已提交
4109 4110
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4111 4112 4113 4114 4115 4116 4117
    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    bSig = extractFloat64Frac( b );
    bExp = extractFloat64Exp( b );
    if ( aExp == 0x7FF ) {
        if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) {
P
Peter Maydell 已提交
4118
            return propagateFloat64NaN(a, b, status);
B
bellard 已提交
4119
        }
P
Peter Maydell 已提交
4120
        float_raise(float_flag_invalid, status);
4121
        return float64_default_nan(status);
B
bellard 已提交
4122 4123
    }
    if ( bExp == 0x7FF ) {
P
Peter Maydell 已提交
4124 4125 4126
        if (bSig) {
            return propagateFloat64NaN(a, b, status);
        }
B
bellard 已提交
4127 4128 4129 4130
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
P
Peter Maydell 已提交
4131
            float_raise(float_flag_invalid, status);
4132
            return float64_default_nan(status);
B
bellard 已提交
4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171
        }
        normalizeFloat64Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return a;
        normalizeFloat64Subnormal( aSig, &aExp, &aSig );
    }
    expDiff = aExp - bExp;
    aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<11;
    bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11;
    if ( expDiff < 0 ) {
        if ( expDiff < -1 ) return a;
        aSig >>= 1;
    }
    q = ( bSig <= aSig );
    if ( q ) aSig -= bSig;
    expDiff -= 64;
    while ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig, 0, bSig );
        q = ( 2 < q ) ? q - 2 : 0;
        aSig = - ( ( bSig>>2 ) * q );
        expDiff -= 62;
    }
    expDiff += 64;
    if ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig, 0, bSig );
        q = ( 2 < q ) ? q - 2 : 0;
        q >>= 64 - expDiff;
        bSig >>= 2;
        aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q;
    }
    else {
        aSig >>= 2;
        bSig >>= 2;
    }
    do {
        alternateASig = aSig;
        ++q;
        aSig -= bSig;
4172
    } while ( 0 <= (int64_t) aSig );
B
bellard 已提交
4173 4174 4175 4176
    sigMean = aSig + alternateASig;
    if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
        aSig = alternateASig;
    }
4177
    zSign = ( (int64_t) aSig < 0 );
B
bellard 已提交
4178
    if ( zSign ) aSig = - aSig;
P
Peter Maydell 已提交
4179
    return normalizeRoundAndPackFloat64(aSign ^ zSign, bExp, aSig, status);
B
bellard 已提交
4180 4181 4182

}

4183 4184 4185 4186 4187
/*----------------------------------------------------------------------------
| Returns the binary log of the double-precision floating-point value `a'.
| The operation is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/
4188
float64 float64_log2(float64 a, float_status *status)
4189 4190
{
    flag aSign, zSign;
4191
    int aExp;
4192
    uint64_t aSig, aSig0, aSig1, zSig, i;
P
Peter Maydell 已提交
4193
    a = float64_squash_input_denormal(a, status);
4194 4195 4196 4197 4198 4199 4200 4201 4202 4203

    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );

    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat64( 1, 0x7FF, 0 );
        normalizeFloat64Subnormal( aSig, &aExp, &aSig );
    }
    if ( aSign ) {
P
Peter Maydell 已提交
4204
        float_raise(float_flag_invalid, status);
4205
        return float64_default_nan(status);
4206 4207
    }
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4208 4209 4210
        if (aSig) {
            return propagateFloat64NaN(a, float64_zero, status);
        }
4211 4212 4213 4214 4215 4216
        return a;
    }

    aExp -= 0x3FF;
    aSig |= LIT64( 0x0010000000000000 );
    zSign = aExp < 0;
4217
    zSig = (uint64_t)aExp << 52;
4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228
    for (i = 1LL << 51; i > 0; i >>= 1) {
        mul64To128( aSig, aSig, &aSig0, &aSig1 );
        aSig = ( aSig0 << 12 ) | ( aSig1 >> 52 );
        if ( aSig & LIT64( 0x0020000000000000 ) ) {
            aSig >>= 1;
            zSig |= i;
        }
    }

    if ( zSign )
        zSig = -zSig;
P
Peter Maydell 已提交
4229
    return normalizeRoundAndPackFloat64(zSign, 0x408, zSig, status);
4230 4231
}

B
bellard 已提交
4232 4233
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is equal to the
4234 4235
| corresponding value `b', and 0 otherwise.  The invalid exception is raised
| if either operand is a NaN.  Otherwise, the comparison is performed
B
bellard 已提交
4236 4237 4238
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

4239
int float64_eq(float64 a, float64 b, float_status *status)
B
bellard 已提交
4240
{
4241
    uint64_t av, bv;
P
Peter Maydell 已提交
4242 4243
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4244 4245 4246 4247

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4248
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4249 4250
        return 0;
    }
P
pbrook 已提交
4251
    av = float64_val(a);
P
pbrook 已提交
4252
    bv = float64_val(b);
4253
    return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
4254 4255 4256 4257 4258

}

/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is less than or
4259 4260 4261
| equal to the corresponding value `b', and 0 otherwise.  The invalid
| exception is raised if either operand is a NaN.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
4262 4263
*----------------------------------------------------------------------------*/

4264
int float64_le(float64 a, float64 b, float_status *status)
B
bellard 已提交
4265 4266
{
    flag aSign, bSign;
4267
    uint64_t av, bv;
P
Peter Maydell 已提交
4268 4269
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4270 4271 4272 4273

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4274
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4275 4276 4277 4278
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4279
    av = float64_val(a);
P
pbrook 已提交
4280
    bv = float64_val(b);
4281
    if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
4282
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
4283 4284 4285 4286 4287

}

/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is less than
4288 4289 4290
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  The comparison is performed according
| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
4291 4292
*----------------------------------------------------------------------------*/

4293
int float64_lt(float64 a, float64 b, float_status *status)
B
bellard 已提交
4294 4295
{
    flag aSign, bSign;
4296
    uint64_t av, bv;
B
bellard 已提交
4297

P
Peter Maydell 已提交
4298 4299
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4300 4301 4302
    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4303
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4304 4305 4306 4307
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4308
    av = float64_val(a);
P
pbrook 已提交
4309
    bv = float64_val(b);
4310
    if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
4311
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
4312 4313 4314

}

4315 4316
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point values `a' and `b' cannot
4317 4318 4319
| be compared, and 0 otherwise.  The invalid exception is raised if either
| operand is a NaN.  The comparison is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
4320 4321
*----------------------------------------------------------------------------*/

4322
int float64_unordered(float64 a, float64 b, float_status *status)
4323
{
P
Peter Maydell 已提交
4324 4325
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
4326 4327 4328 4329

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4330
        float_raise(float_flag_invalid, status);
4331 4332 4333 4334 4335
        return 1;
    }
    return 0;
}

B
bellard 已提交
4336 4337
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is equal to the
4338 4339 4340
| corresponding value `b', and 0 otherwise.  Quiet NaNs do not cause an
| exception.The comparison is performed according to the IEC/IEEE Standard
| for Binary Floating-Point Arithmetic.
B
bellard 已提交
4341 4342
*----------------------------------------------------------------------------*/

4343
int float64_eq_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4344
{
4345
    uint64_t av, bv;
P
Peter Maydell 已提交
4346 4347
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4348 4349 4350 4351

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4352 4353
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4354
            float_raise(float_flag_invalid, status);
4355
        }
B
bellard 已提交
4356 4357
        return 0;
    }
P
pbrook 已提交
4358
    av = float64_val(a);
P
pbrook 已提交
4359
    bv = float64_val(b);
4360
    return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
4361 4362 4363 4364 4365 4366 4367 4368 4369 4370

}

/*----------------------------------------------------------------------------
| Returns 1 if the 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.
*----------------------------------------------------------------------------*/

4371
int float64_le_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4372 4373
{
    flag aSign, bSign;
4374
    uint64_t av, bv;
P
Peter Maydell 已提交
4375 4376
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4377 4378 4379 4380

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4381 4382
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4383
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4384 4385 4386 4387 4388
        }
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4389
    av = float64_val(a);
P
pbrook 已提交
4390
    bv = float64_val(b);
4391
    if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
4392
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
4393 4394 4395 4396 4397 4398 4399 4400 4401 4402

}

/*----------------------------------------------------------------------------
| Returns 1 if the 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.
*----------------------------------------------------------------------------*/

4403
int float64_lt_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4404 4405
{
    flag aSign, bSign;
4406
    uint64_t av, bv;
P
Peter Maydell 已提交
4407 4408
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4409 4410 4411 4412

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4413 4414
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4415
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4416 4417 4418 4419 4420
        }
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4421
    av = float64_val(a);
P
pbrook 已提交
4422
    bv = float64_val(b);
4423
    if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
4424
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
4425 4426 4427

}

4428 4429 4430 4431 4432 4433 4434
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point values `a' and `b' cannot
| be compared, and 0 otherwise.  Quiet NaNs do not cause an exception.  The
| comparison is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

4435
int float64_unordered_quiet(float64 a, float64 b, float_status *status)
4436
{
P
Peter Maydell 已提交
4437 4438
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
4439 4440 4441 4442

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4443 4444
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4445
            float_raise(float_flag_invalid, status);
4446 4447 4448 4449 4450 4451
        }
        return 1;
    }
    return 0;
}

B
bellard 已提交
4452 4453 4454 4455 4456 4457 4458 4459 4460 4461
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4462
int32_t floatx80_to_int32(floatx80 a, float_status *status)
B
bellard 已提交
4463 4464
{
    flag aSign;
4465
    int32_t aExp, shiftCount;
4466
    uint64_t aSig;
B
bellard 已提交
4467

4468 4469 4470 4471
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1 << 31;
    }
B
bellard 已提交
4472 4473 4474
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
4475
    if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0;
B
bellard 已提交
4476 4477 4478
    shiftCount = 0x4037 - aExp;
    if ( shiftCount <= 0 ) shiftCount = 1;
    shift64RightJamming( aSig, shiftCount, &aSig );
P
Peter Maydell 已提交
4479
    return roundAndPackInt32(aSign, aSig, status);
B
bellard 已提交
4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4493
int32_t floatx80_to_int32_round_to_zero(floatx80 a, float_status *status)
B
bellard 已提交
4494 4495
{
    flag aSign;
4496
    int32_t aExp, shiftCount;
4497
    uint64_t aSig, savedASig;
4498
    int32_t z;
B
bellard 已提交
4499

4500 4501 4502 4503
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1 << 31;
    }
B
bellard 已提交
4504 4505 4506 4507
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( 0x401E < aExp ) {
4508
        if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0;
B
bellard 已提交
4509 4510 4511
        goto invalid;
    }
    else if ( aExp < 0x3FFF ) {
4512 4513 4514
        if (aExp || aSig) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
4515 4516 4517 4518 4519 4520 4521 4522 4523
        return 0;
    }
    shiftCount = 0x403E - aExp;
    savedASig = aSig;
    aSig >>= shiftCount;
    z = aSig;
    if ( aSign ) z = - z;
    if ( ( z < 0 ) ^ aSign ) {
 invalid:
P
Peter Maydell 已提交
4524
        float_raise(float_flag_invalid, status);
4525
        return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
4526 4527
    }
    if ( ( aSig<<shiftCount ) != savedASig ) {
4528
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543
    }
    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.
*----------------------------------------------------------------------------*/

4544
int64_t floatx80_to_int64(floatx80 a, float_status *status)
B
bellard 已提交
4545 4546
{
    flag aSign;
4547
    int32_t aExp, shiftCount;
4548
    uint64_t aSig, aSigExtra;
B
bellard 已提交
4549

4550 4551 4552 4553
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1ULL << 63;
    }
B
bellard 已提交
4554 4555 4556 4557 4558 4559
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    shiftCount = 0x403E - aExp;
    if ( shiftCount <= 0 ) {
        if ( shiftCount ) {
P
Peter Maydell 已提交
4560
            float_raise(float_flag_invalid, status);
4561
            if (!aSign || floatx80_is_any_nan(a)) {
B
bellard 已提交
4562 4563
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
4564
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
4565 4566 4567 4568 4569 4570
        }
        aSigExtra = 0;
    }
    else {
        shift64ExtraRightJamming( aSig, 0, shiftCount, &aSig, &aSigExtra );
    }
P
Peter Maydell 已提交
4571
    return roundAndPackInt64(aSign, aSig, aSigExtra, status);
B
bellard 已提交
4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4585
int64_t floatx80_to_int64_round_to_zero(floatx80 a, float_status *status)
B
bellard 已提交
4586 4587
{
    flag aSign;
4588
    int32_t aExp, shiftCount;
4589
    uint64_t aSig;
4590
    int64_t z;
B
bellard 已提交
4591

4592 4593 4594 4595
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1ULL << 63;
    }
B
bellard 已提交
4596 4597 4598 4599 4600 4601 4602
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    shiftCount = aExp - 0x403E;
    if ( 0 <= shiftCount ) {
        aSig &= LIT64( 0x7FFFFFFFFFFFFFFF );
        if ( ( a.high != 0xC03E ) || aSig ) {
P
Peter Maydell 已提交
4603
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4604 4605 4606 4607
            if ( ! aSign || ( ( aExp == 0x7FFF ) && aSig ) ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
        }
4608
        return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
4609 4610
    }
    else if ( aExp < 0x3FFF ) {
4611 4612 4613
        if (aExp | aSig) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
4614 4615 4616
        return 0;
    }
    z = aSig>>( - shiftCount );
4617
    if ( (uint64_t) ( aSig<<( shiftCount & 63 ) ) ) {
4618
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631
    }
    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.
*----------------------------------------------------------------------------*/

4632
float32 floatx80_to_float32(floatx80 a, float_status *status)
B
bellard 已提交
4633 4634
{
    flag aSign;
4635
    int32_t aExp;
4636
    uint64_t aSig;
B
bellard 已提交
4637

4638 4639 4640 4641
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float32_default_nan(status);
    }
B
bellard 已提交
4642 4643 4644 4645
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
4646
        if ( (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4647
            return commonNaNToFloat32(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4648 4649 4650 4651 4652
        }
        return packFloat32( aSign, 0xFF, 0 );
    }
    shift64RightJamming( aSig, 33, &aSig );
    if ( aExp || aSig ) aExp -= 0x3F81;
P
Peter Maydell 已提交
4653
    return roundAndPackFloat32(aSign, aExp, aSig, status);
B
bellard 已提交
4654 4655 4656 4657 4658 4659 4660 4661 4662 4663

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4664
float64 floatx80_to_float64(floatx80 a, float_status *status)
B
bellard 已提交
4665 4666
{
    flag aSign;
4667
    int32_t aExp;
4668
    uint64_t aSig, zSig;
B
bellard 已提交
4669

4670 4671 4672 4673
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float64_default_nan(status);
    }
B
bellard 已提交
4674 4675 4676 4677
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
4678
        if ( (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4679
            return commonNaNToFloat64(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4680 4681 4682 4683 4684
        }
        return packFloat64( aSign, 0x7FF, 0 );
    }
    shift64RightJamming( aSig, 1, &zSig );
    if ( aExp || aSig ) aExp -= 0x3C01;
P
Peter Maydell 已提交
4685
    return roundAndPackFloat64(aSign, aExp, zSig, status);
B
bellard 已提交
4686 4687 4688 4689 4690 4691 4692 4693 4694 4695

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4696
float128 floatx80_to_float128(floatx80 a, float_status *status)
B
bellard 已提交
4697 4698
{
    flag aSign;
4699
    int aExp;
4700
    uint64_t aSig, zSig0, zSig1;
B
bellard 已提交
4701

4702 4703 4704 4705
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float128_default_nan(status);
    }
B
bellard 已提交
4706 4707 4708
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
4709
    if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4710
        return commonNaNToFloat128(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4711 4712 4713 4714 4715 4716
    }
    shift128Right( aSig<<1, 0, 16, &zSig0, &zSig1 );
    return packFloat128( aSign, aExp, zSig0, zSig1 );

}

4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732
/*----------------------------------------------------------------------------
| Rounds the extended double-precision floating-point value `a'
| to the precision provided by floatx80_rounding_precision and returns the
| result as an extended double-precision floating-point value.
| The operation is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

floatx80 floatx80_round(floatx80 a, float_status *status)
{
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
                                extractFloatx80Sign(a),
                                extractFloatx80Exp(a),
                                extractFloatx80Frac(a), 0, status);
}

B
bellard 已提交
4733 4734 4735 4736 4737 4738 4739
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4740
floatx80 floatx80_round_to_int(floatx80 a, float_status *status)
B
bellard 已提交
4741 4742
{
    flag aSign;
4743
    int32_t aExp;
4744
    uint64_t lastBitMask, roundBitsMask;
B
bellard 已提交
4745 4746
    floatx80 z;

4747 4748 4749 4750
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
4751 4752
    aExp = extractFloatx80Exp( a );
    if ( 0x403E <= aExp ) {
4753
        if ( ( aExp == 0x7FFF ) && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) {
P
Peter Maydell 已提交
4754
            return propagateFloatx80NaN(a, a, status);
B
bellard 已提交
4755 4756 4757 4758 4759
        }
        return a;
    }
    if ( aExp < 0x3FFF ) {
        if (    ( aExp == 0 )
4760
             && ( (uint64_t) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) {
B
bellard 已提交
4761 4762
            return a;
        }
4763
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4764
        aSign = extractFloatx80Sign( a );
4765
        switch (status->float_rounding_mode) {
B
bellard 已提交
4766
         case float_round_nearest_even:
4767
            if ( ( aExp == 0x3FFE ) && (uint64_t) ( extractFloatx80Frac( a )<<1 )
B
bellard 已提交
4768 4769 4770 4771 4772
               ) {
                return
                    packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) );
            }
            break;
4773 4774 4775 4776 4777
        case float_round_ties_away:
            if (aExp == 0x3FFE) {
                return packFloatx80(aSign, 0x3FFF, LIT64(0x8000000000000000));
            }
            break;
B
bellard 已提交
4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793
         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;
4794
    switch (status->float_rounding_mode) {
4795
    case float_round_nearest_even:
B
bellard 已提交
4796
        z.low += lastBitMask>>1;
4797 4798 4799 4800
        if ((z.low & roundBitsMask) == 0) {
            z.low &= ~lastBitMask;
        }
        break;
4801 4802 4803
    case float_round_ties_away:
        z.low += lastBitMask >> 1;
        break;
4804 4805 4806 4807 4808 4809 4810 4811 4812
    case float_round_to_zero:
        break;
    case float_round_up:
        if (!extractFloatx80Sign(z)) {
            z.low += roundBitsMask;
        }
        break;
    case float_round_down:
        if (extractFloatx80Sign(z)) {
B
bellard 已提交
4813 4814
            z.low += roundBitsMask;
        }
4815 4816 4817
        break;
    default:
        abort();
B
bellard 已提交
4818 4819 4820 4821 4822 4823
    }
    z.low &= ~ roundBitsMask;
    if ( z.low == 0 ) {
        ++z.high;
        z.low = LIT64( 0x8000000000000000 );
    }
4824 4825 4826
    if (z.low != a.low) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838
    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.
*----------------------------------------------------------------------------*/

4839 4840
static floatx80 addFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
                                float_status *status)
B
bellard 已提交
4841
{
4842
    int32_t aExp, bExp, zExp;
4843
    uint64_t aSig, bSig, zSig0, zSig1;
4844
    int32_t expDiff;
B
bellard 已提交
4845 4846 4847 4848 4849 4850 4851 4852

    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    expDiff = aExp - bExp;
    if ( 0 < expDiff ) {
        if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
4853 4854 4855
            if ((uint64_t)(aSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
B
bellard 已提交
4856 4857 4858 4859 4860 4861 4862 4863
            return a;
        }
        if ( bExp == 0 ) --expDiff;
        shift64ExtraRightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
        zExp = aExp;
    }
    else if ( expDiff < 0 ) {
        if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
4864 4865 4866
            if ((uint64_t)(bSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
4867 4868 4869
            return packFloatx80(zSign,
                                floatx80_infinity_high,
                                floatx80_infinity_low);
B
bellard 已提交
4870 4871 4872 4873 4874 4875 4876
        }
        if ( aExp == 0 ) ++expDiff;
        shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
        zExp = bExp;
    }
    else {
        if ( aExp == 0x7FFF ) {
4877
            if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) {
P
Peter Maydell 已提交
4878
                return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891
            }
            return a;
        }
        zSig1 = 0;
        zSig0 = aSig + bSig;
        if ( aExp == 0 ) {
            normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 );
            goto roundAndPack;
        }
        zExp = aExp;
        goto shiftRight1;
    }
    zSig0 = aSig + bSig;
4892
    if ( (int64_t) zSig0 < 0 ) goto roundAndPack;
B
bellard 已提交
4893 4894 4895 4896 4897
 shiftRight1:
    shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 );
    zSig0 |= LIT64( 0x8000000000000000 );
    ++zExp;
 roundAndPack:
4898
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
4899
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
4900 4901 4902 4903 4904 4905 4906 4907 4908 4909
}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4910 4911
static floatx80 subFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
                                float_status *status)
B
bellard 已提交
4912
{
4913
    int32_t aExp, bExp, zExp;
4914
    uint64_t aSig, bSig, zSig0, zSig1;
4915
    int32_t expDiff;
B
bellard 已提交
4916 4917 4918 4919 4920 4921 4922 4923 4924

    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 ) {
4925
        if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) {
P
Peter Maydell 已提交
4926
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
4927
        }
P
Peter Maydell 已提交
4928
        float_raise(float_flag_invalid, status);
4929
        return floatx80_default_nan(status);
B
bellard 已提交
4930 4931 4932 4933 4934 4935 4936 4937
    }
    if ( aExp == 0 ) {
        aExp = 1;
        bExp = 1;
    }
    zSig1 = 0;
    if ( bSig < aSig ) goto aBigger;
    if ( aSig < bSig ) goto bBigger;
4938
    return packFloatx80(status->float_rounding_mode == float_round_down, 0, 0);
B
bellard 已提交
4939 4940
 bExpBigger:
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
4941 4942 4943
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
4944 4945
        return packFloatx80(zSign ^ 1, floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
4946 4947 4948 4949 4950 4951 4952 4953 4954 4955
    }
    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 ) {
P
Peter Maydell 已提交
4956 4957 4958
        if ((uint64_t)(aSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
4959 4960 4961 4962 4963 4964 4965 4966
        return a;
    }
    if ( bExp == 0 ) --expDiff;
    shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
 aBigger:
    sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 );
    zExp = aExp;
 normalizeRoundAndPack:
4967
    return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
4968
                                         zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
4969 4970 4971 4972 4973 4974 4975 4976
}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4977
floatx80 floatx80_add(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
4978 4979 4980
{
    flag aSign, bSign;

4981 4982 4983 4984
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
4985 4986 4987
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
4988
        return addFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
4989 4990
    }
    else {
P
Peter Maydell 已提交
4991
        return subFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
4992 4993 4994 4995 4996 4997 4998 4999 5000 5001
    }

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5002
floatx80 floatx80_sub(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5003 5004 5005
{
    flag aSign, bSign;

5006 5007 5008 5009
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5010 5011 5012
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
5013
        return subFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5014 5015
    }
    else {
P
Peter Maydell 已提交
5016
        return addFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5017 5018 5019 5020 5021 5022 5023 5024 5025 5026
    }

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5027
floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5028 5029
{
    flag aSign, bSign, zSign;
5030
    int32_t aExp, bExp, zExp;
5031
    uint64_t aSig, bSig, zSig0, zSig1;
B
bellard 已提交
5032

5033 5034 5035 5036
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5037 5038 5039 5040 5041 5042 5043 5044
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
5045 5046
        if (    (uint64_t) ( aSig<<1 )
             || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) {
P
Peter Maydell 已提交
5047
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
5048 5049
        }
        if ( ( bExp | bSig ) == 0 ) goto invalid;
5050 5051
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5052 5053
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5054 5055 5056
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5057 5058
        if ( ( aExp | aSig ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
5059
            float_raise(float_flag_invalid, status);
5060
            return floatx80_default_nan(status);
B
bellard 已提交
5061
        }
5062 5063
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074
    }
    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 );
5075
    if ( 0 < (int64_t) zSig0 ) {
B
bellard 已提交
5076 5077 5078
        shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 );
        --zExp;
    }
5079
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
5080
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
5081 5082 5083 5084 5085 5086 5087 5088
}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5089
floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5090 5091
{
    flag aSign, bSign, zSign;
5092
    int32_t aExp, bExp, zExp;
5093 5094
    uint64_t aSig, bSig, zSig0, zSig1;
    uint64_t rem0, rem1, rem2, term0, term1, term2;
B
bellard 已提交
5095

5096 5097 5098 5099
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5100 5101 5102 5103 5104 5105 5106 5107
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
5108 5109 5110
        if ((uint64_t)(aSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5111
        if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5112 5113 5114
            if ((uint64_t)(bSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
B
bellard 已提交
5115 5116
            goto invalid;
        }
5117 5118
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5119 5120
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5121 5122 5123
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5124 5125 5126 5127 5128 5129
        return packFloatx80( zSign, 0, 0 );
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
            if ( ( aExp | aSig ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
5130
                float_raise(float_flag_invalid, status);
5131
                return floatx80_default_nan(status);
B
bellard 已提交
5132
            }
P
Peter Maydell 已提交
5133
            float_raise(float_flag_divbyzero, status);
5134 5135
            return packFloatx80(zSign, floatx80_infinity_high,
                                       floatx80_infinity_low);
B
bellard 已提交
5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151
        }
        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 );
5152
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
5153 5154 5155 5156
        --zSig0;
        add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
    }
    zSig1 = estimateDiv128To64( rem1, 0, bSig );
5157
    if ( (uint64_t) ( zSig1<<1 ) <= 8 ) {
B
bellard 已提交
5158 5159
        mul64To128( bSig, zSig1, &term1, &term2 );
        sub128( rem1, 0, term1, term2, &rem1, &rem2 );
5160
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
5161 5162 5163 5164 5165
            --zSig1;
            add128( rem1, rem2, 0, bSig, &rem1, &rem2 );
        }
        zSig1 |= ( ( rem1 | rem2 ) != 0 );
    }
5166
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
5167
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
5168 5169 5170 5171 5172 5173 5174 5175
}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5176
floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5177
{
5178
    flag aSign, zSign;
5179
    int32_t aExp, bExp, expDiff;
5180 5181
    uint64_t aSig0, aSig1, bSig;
    uint64_t q, term0, term1, alternateASig0, alternateASig1;
B
bellard 已提交
5182

5183 5184 5185 5186
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5187 5188 5189 5190 5191 5192
    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    if ( aExp == 0x7FFF ) {
5193 5194
        if (    (uint64_t) ( aSig0<<1 )
             || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) {
P
Peter Maydell 已提交
5195
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
5196 5197 5198 5199
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5200 5201 5202
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5203 5204 5205 5206 5207
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
 invalid:
P
Peter Maydell 已提交
5208
            float_raise(float_flag_invalid, status);
5209
            return floatx80_default_nan(status);
B
bellard 已提交
5210 5211 5212 5213
        }
        normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
5214
        if ( (uint64_t) ( aSig0<<1 ) == 0 ) return a;
B
bellard 已提交
5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264
        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(
P
Peter Maydell 已提交
5265
            80, zSign, bExp + expDiff, aSig0, aSig1, status);
B
bellard 已提交
5266 5267 5268 5269 5270 5271 5272 5273 5274

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5275
floatx80 floatx80_sqrt(floatx80 a, float_status *status)
B
bellard 已提交
5276 5277
{
    flag aSign;
5278
    int32_t aExp, zExp;
5279 5280
    uint64_t aSig0, aSig1, zSig0, zSig1, doubleZSig0;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
5281

5282 5283 5284 5285
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5286 5287 5288 5289
    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
5290 5291 5292
        if ((uint64_t)(aSig0 << 1)) {
            return propagateFloatx80NaN(a, a, status);
        }
B
bellard 已提交
5293 5294 5295 5296 5297 5298
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 ) == 0 ) return a;
 invalid:
P
Peter Maydell 已提交
5299
        float_raise(float_flag_invalid, status);
5300
        return floatx80_default_nan(status);
B
bellard 已提交
5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312
    }
    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 );
5313
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324
        --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 );
5325
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
5326 5327 5328 5329 5330 5331 5332 5333 5334 5335
            --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;
5336 5337
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
                                0, zExp, zSig0, zSig1, status);
B
bellard 已提交
5338 5339 5340
}

/*----------------------------------------------------------------------------
5341 5342 5343 5344
| 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.
B
bellard 已提交
5345 5346
*----------------------------------------------------------------------------*/

5347
int floatx80_eq(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5348 5349
{

5350 5351 5352 5353 5354
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
        || (extractFloatx80Exp(a) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(a) << 1))
        || (extractFloatx80Exp(b) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(b) << 1))
B
bellard 已提交
5355
       ) {
P
Peter Maydell 已提交
5356
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5357 5358 5359 5360 5361 5362
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
5363
                  && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
5364 5365 5366 5367 5368 5369 5370
           );

}

/*----------------------------------------------------------------------------
| 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
5371 5372 5373
| invalid exception is raised if either operand is a NaN.  The comparison is
| performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
B
bellard 已提交
5374 5375
*----------------------------------------------------------------------------*/

5376
int floatx80_le(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5377 5378 5379
{
    flag aSign, bSign;

5380 5381 5382 5383 5384
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
        || (extractFloatx80Exp(a) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(a) << 1))
        || (extractFloatx80Exp(b) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(b) << 1))
B
bellard 已提交
5385
       ) {
P
Peter Maydell 已提交
5386
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5387 5388 5389 5390 5391 5392 5393
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5394
            || (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5395 5396 5397 5398 5399 5400 5401 5402 5403 5404
                 == 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
5405 5406 5407
| less than the corresponding value `b', and 0 otherwise.  The invalid
| exception is raised if either operand is a NaN.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
5408 5409
*----------------------------------------------------------------------------*/

5410
int floatx80_lt(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5411 5412 5413
{
    flag aSign, bSign;

5414 5415 5416 5417 5418
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
        || (extractFloatx80Exp(a) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(a) << 1))
        || (extractFloatx80Exp(b) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(b) << 1))
B
bellard 已提交
5419
       ) {
P
Peter Maydell 已提交
5420
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5421 5422 5423 5424 5425 5426 5427
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5428
            && (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5429 5430 5431 5432 5433 5434 5435 5436
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

5437 5438
/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point values `a' and `b'
5439 5440 5441
| cannot be compared, and 0 otherwise.  The invalid exception is raised if
| either operand is a NaN.   The comparison is performed according to the
| IEC/IEEE Standard for Binary Floating-Point Arithmetic.
5442
*----------------------------------------------------------------------------*/
5443
int floatx80_unordered(floatx80 a, floatx80 b, float_status *status)
5444
{
5445 5446 5447 5448 5449
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
        || (extractFloatx80Exp(a) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(a) << 1))
        || (extractFloatx80Exp(b) == 0x7FFF
            && (uint64_t) (extractFloatx80Frac(b) << 1))
5450
       ) {
P
Peter Maydell 已提交
5451
        float_raise(float_flag_invalid, status);
5452 5453 5454 5455 5456
        return 1;
    }
    return 0;
}

B
bellard 已提交
5457
/*----------------------------------------------------------------------------
5458
| Returns 1 if the extended double-precision floating-point value `a' is
5459 5460 5461
| equal to the corresponding value `b', and 0 otherwise.  Quiet NaNs do not
| cause an exception.  The comparison is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
5462 5463
*----------------------------------------------------------------------------*/

5464
int floatx80_eq_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5465 5466
{

5467 5468 5469 5470
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5471
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5472
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5473
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5474
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5475
       ) {
5476 5477
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5478
            float_raise(float_flag_invalid, status);
5479
        }
B
bellard 已提交
5480 5481 5482 5483 5484 5485
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
5486
                  && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497
           );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5498
int floatx80_le_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5499 5500 5501
{
    flag aSign, bSign;

5502 5503 5504 5505
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5506
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5507
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5508
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5509
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5510
       ) {
5511 5512
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5513
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5514 5515 5516 5517 5518 5519 5520 5521
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5522
            || (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537
                 == 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.
*----------------------------------------------------------------------------*/

5538
int floatx80_lt_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5539 5540 5541
{
    flag aSign, bSign;

5542 5543 5544 5545
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5546
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5547
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5548
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5549
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5550
       ) {
5551 5552
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5553
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5554 5555 5556 5557 5558 5559 5560 5561
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5562
            && (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5563 5564 5565 5566 5567 5568 5569 5570
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

5571 5572 5573 5574 5575 5576
/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point values `a' and `b'
| cannot be compared, and 0 otherwise.  Quiet NaNs do not cause an exception.
| The comparison is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/
5577
int floatx80_unordered_quiet(floatx80 a, floatx80 b, float_status *status)
5578
{
5579 5580 5581 5582
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 1;
    }
5583 5584 5585 5586 5587
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
       ) {
5588 5589
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5590
            float_raise(float_flag_invalid, status);
5591 5592 5593 5594 5595 5596
        }
        return 1;
    }
    return 0;
}

B
bellard 已提交
5597 5598 5599 5600 5601 5602 5603 5604 5605 5606
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5607
int32_t float128_to_int32(float128 a, float_status *status)
B
bellard 已提交
5608 5609
{
    flag aSign;
5610
    int32_t aExp, shiftCount;
5611
    uint64_t aSig0, aSig1;
B
bellard 已提交
5612 5613 5614 5615 5616 5617 5618 5619 5620 5621

    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 );
P
Peter Maydell 已提交
5622
    return roundAndPackInt32(aSign, aSig0, status);
B
bellard 已提交
5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5636
int32_t float128_to_int32_round_to_zero(float128 a, float_status *status)
B
bellard 已提交
5637 5638
{
    flag aSign;
5639
    int32_t aExp, shiftCount;
5640
    uint64_t aSig0, aSig1, savedASig;
5641
    int32_t z;
B
bellard 已提交
5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652

    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 ) {
5653 5654 5655
        if (aExp || aSig0) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
5656 5657 5658 5659 5660 5661 5662 5663 5664 5665
        return 0;
    }
    aSig0 |= LIT64( 0x0001000000000000 );
    shiftCount = 0x402F - aExp;
    savedASig = aSig0;
    aSig0 >>= shiftCount;
    z = aSig0;
    if ( aSign ) z = - z;
    if ( ( z < 0 ) ^ aSign ) {
 invalid:
P
Peter Maydell 已提交
5666
        float_raise(float_flag_invalid, status);
5667
        return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
5668 5669
    }
    if ( ( aSig0<<shiftCount ) != savedASig ) {
5670
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685
    }
    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.
*----------------------------------------------------------------------------*/

5686
int64_t float128_to_int64(float128 a, float_status *status)
B
bellard 已提交
5687 5688
{
    flag aSign;
5689
    int32_t aExp, shiftCount;
5690
    uint64_t aSig0, aSig1;
B
bellard 已提交
5691 5692 5693 5694 5695 5696 5697 5698 5699

    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 ) {
P
Peter Maydell 已提交
5700
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5701 5702 5703 5704 5705 5706 5707
            if (    ! aSign
                 || (    ( aExp == 0x7FFF )
                      && ( aSig1 || ( aSig0 != LIT64( 0x0001000000000000 ) ) )
                    )
               ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
5708
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
5709 5710 5711 5712 5713 5714
        }
        shortShift128Left( aSig0, aSig1, - shiftCount, &aSig0, &aSig1 );
    }
    else {
        shift64ExtraRightJamming( aSig0, aSig1, shiftCount, &aSig0, &aSig1 );
    }
P
Peter Maydell 已提交
5715
    return roundAndPackInt64(aSign, aSig0, aSig1, status);
B
bellard 已提交
5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726 5727 5728

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5729
int64_t float128_to_int64_round_to_zero(float128 a, float_status *status)
B
bellard 已提交
5730 5731
{
    flag aSign;
5732
    int32_t aExp, shiftCount;
5733
    uint64_t aSig0, aSig1;
5734
    int64_t z;
B
bellard 已提交
5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746

    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 ) ) ) {
5747 5748 5749
                if (aSig1) {
                    status->float_exception_flags |= float_flag_inexact;
                }
B
bellard 已提交
5750 5751
            }
            else {
P
Peter Maydell 已提交
5752
                float_raise(float_flag_invalid, status);
B
bellard 已提交
5753 5754 5755 5756
                if ( ! aSign || ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) ) {
                    return LIT64( 0x7FFFFFFFFFFFFFFF );
                }
            }
5757
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
5758 5759
        }
        z = ( aSig0<<shiftCount ) | ( aSig1>>( ( - shiftCount ) & 63 ) );
5760
        if ( (uint64_t) ( aSig1<<shiftCount ) ) {
5761
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5762 5763 5764 5765 5766
        }
    }
    else {
        if ( aExp < 0x3FFF ) {
            if ( aExp | aSig0 | aSig1 ) {
5767
                status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5768 5769 5770 5771 5772
            }
            return 0;
        }
        z = aSig0>>( - shiftCount );
        if (    aSig1
5773
             || ( shiftCount && (uint64_t) ( aSig0<<( shiftCount & 63 ) ) ) ) {
5774
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5775 5776 5777 5778 5779 5780 5781
        }
    }
    if ( aSign ) z = - z;
    return z;

}

5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840
/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point value
| `a' to the 64-bit unsigned 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.  If the conversion overflows, the
| largest unsigned integer is returned.  If 'a' is negative, the value is
| rounded and zero is returned; negative values that do not round to zero
| will raise the inexact exception.
*----------------------------------------------------------------------------*/

uint64_t float128_to_uint64(float128 a, float_status *status)
{
    flag aSign;
    int aExp;
    int shiftCount;
    uint64_t aSig0, aSig1;

    aSig0 = extractFloat128Frac0(a);
    aSig1 = extractFloat128Frac1(a);
    aExp = extractFloat128Exp(a);
    aSign = extractFloat128Sign(a);
    if (aSign && (aExp > 0x3FFE)) {
        float_raise(float_flag_invalid, status);
        if (float128_is_any_nan(a)) {
            return LIT64(0xFFFFFFFFFFFFFFFF);
        } else {
            return 0;
        }
    }
    if (aExp) {
        aSig0 |= LIT64(0x0001000000000000);
    }
    shiftCount = 0x402F - aExp;
    if (shiftCount <= 0) {
        if (0x403E < aExp) {
            float_raise(float_flag_invalid, status);
            return LIT64(0xFFFFFFFFFFFFFFFF);
        }
        shortShift128Left(aSig0, aSig1, -shiftCount, &aSig0, &aSig1);
    } else {
        shift64ExtraRightJamming(aSig0, aSig1, shiftCount, &aSig0, &aSig1);
    }
    return roundAndPackUint64(aSign, aSig0, aSig1, status);
}

uint64_t float128_to_uint64_round_to_zero(float128 a, float_status *status)
{
    uint64_t v;
    signed char current_rounding_mode = status->float_rounding_mode;

    set_float_rounding_mode(float_round_to_zero, status);
    v = float128_to_uint64(a, status);
    set_float_rounding_mode(current_rounding_mode, status);

    return v;
}

B
bellard 已提交
5841 5842
/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
5843 5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870
| value `a' to the 32-bit unsigned 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 unsigned integer is returned.
| If 'a' is negative, the value is rounded and zero is returned; negative
| values that do not round to zero will raise the inexact exception.
*----------------------------------------------------------------------------*/

uint32_t float128_to_uint32_round_to_zero(float128 a, float_status *status)
{
    uint64_t v;
    uint32_t res;
    int old_exc_flags = get_float_exception_flags(status);

    v = float128_to_uint64_round_to_zero(a, status);
    if (v > 0xffffffff) {
        res = 0xffffffff;
    } else {
        return v;
    }
    set_float_exception_flags(old_exc_flags, status);
    float_raise(float_flag_invalid, status);
    return res;
}

/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
B
bellard 已提交
5871 5872 5873 5874 5875
| value `a' to the single-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

5876
float32 float128_to_float32(float128 a, float_status *status)
B
bellard 已提交
5877 5878
{
    flag aSign;
5879
    int32_t aExp;
5880 5881
    uint64_t aSig0, aSig1;
    uint32_t zSig;
B
bellard 已提交
5882 5883 5884 5885 5886 5887 5888

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5889
            return commonNaNToFloat32(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5890 5891 5892 5893 5894 5895 5896 5897 5898 5899
        }
        return packFloat32( aSign, 0xFF, 0 );
    }
    aSig0 |= ( aSig1 != 0 );
    shift64RightJamming( aSig0, 18, &aSig0 );
    zSig = aSig0;
    if ( aExp || zSig ) {
        zSig |= 0x40000000;
        aExp -= 0x3F81;
    }
P
Peter Maydell 已提交
5900
    return roundAndPackFloat32(aSign, aExp, zSig, status);
B
bellard 已提交
5901 5902 5903 5904 5905 5906 5907 5908 5909 5910

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5911
float64 float128_to_float64(float128 a, float_status *status)
B
bellard 已提交
5912 5913
{
    flag aSign;
5914
    int32_t aExp;
5915
    uint64_t aSig0, aSig1;
B
bellard 已提交
5916 5917 5918 5919 5920 5921 5922

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5923
            return commonNaNToFloat64(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5924 5925 5926 5927 5928 5929 5930 5931 5932
        }
        return packFloat64( aSign, 0x7FF, 0 );
    }
    shortShift128Left( aSig0, aSig1, 14, &aSig0, &aSig1 );
    aSig0 |= ( aSig1 != 0 );
    if ( aExp || aSig0 ) {
        aSig0 |= LIT64( 0x4000000000000000 );
        aExp -= 0x3C01;
    }
P
Peter Maydell 已提交
5933
    return roundAndPackFloat64(aSign, aExp, aSig0, status);
B
bellard 已提交
5934 5935 5936 5937 5938 5939 5940 5941 5942 5943

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5944
floatx80 float128_to_floatx80(float128 a, float_status *status)
B
bellard 已提交
5945 5946
{
    flag aSign;
5947
    int32_t aExp;
5948
    uint64_t aSig0, aSig1;
B
bellard 已提交
5949 5950 5951 5952 5953 5954 5955

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5956
            return commonNaNToFloatx80(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5957
        }
5958 5959
        return packFloatx80(aSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5960 5961 5962 5963 5964 5965 5966 5967 5968
    }
    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 );
P
Peter Maydell 已提交
5969
    return roundAndPackFloatx80(80, aSign, aExp, aSig0, aSig1, status);
B
bellard 已提交
5970 5971 5972 5973 5974 5975 5976 5977 5978 5979

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5980
float128 float128_round_to_int(float128 a, float_status *status)
B
bellard 已提交
5981 5982
{
    flag aSign;
5983
    int32_t aExp;
5984
    uint64_t lastBitMask, roundBitsMask;
B
bellard 已提交
5985 5986 5987 5988 5989 5990 5991 5992
    float128 z;

    aExp = extractFloat128Exp( a );
    if ( 0x402F <= aExp ) {
        if ( 0x406F <= aExp ) {
            if (    ( aExp == 0x7FFF )
                 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) )
               ) {
P
Peter Maydell 已提交
5993
                return propagateFloat128NaN(a, a, status);
B
bellard 已提交
5994 5995 5996 5997 5998 5999 6000
            }
            return a;
        }
        lastBitMask = 1;
        lastBitMask = ( lastBitMask<<( 0x406E - aExp ) )<<1;
        roundBitsMask = lastBitMask - 1;
        z = a;
6001
        switch (status->float_rounding_mode) {
6002
        case float_round_nearest_even:
B
bellard 已提交
6003 6004 6005 6006 6007
            if ( lastBitMask ) {
                add128( z.high, z.low, 0, lastBitMask>>1, &z.high, &z.low );
                if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask;
            }
            else {
6008
                if ( (int64_t) z.low < 0 ) {
B
bellard 已提交
6009
                    ++z.high;
6010
                    if ( (uint64_t) ( z.low<<1 ) == 0 ) z.high &= ~1;
B
bellard 已提交
6011 6012
                }
            }
6013
            break;
6014 6015 6016 6017 6018 6019 6020 6021 6022
        case float_round_ties_away:
            if (lastBitMask) {
                add128(z.high, z.low, 0, lastBitMask >> 1, &z.high, &z.low);
            } else {
                if ((int64_t) z.low < 0) {
                    ++z.high;
                }
            }
            break;
6023 6024 6025 6026 6027 6028 6029 6030 6031 6032
        case float_round_to_zero:
            break;
        case float_round_up:
            if (!extractFloat128Sign(z)) {
                add128(z.high, z.low, 0, roundBitsMask, &z.high, &z.low);
            }
            break;
        case float_round_down:
            if (extractFloat128Sign(z)) {
                add128(z.high, z.low, 0, roundBitsMask, &z.high, &z.low);
B
bellard 已提交
6033
            }
6034 6035 6036
            break;
        default:
            abort();
B
bellard 已提交
6037 6038 6039 6040 6041
        }
        z.low &= ~ roundBitsMask;
    }
    else {
        if ( aExp < 0x3FFF ) {
6042
            if ( ( ( (uint64_t) ( a.high<<1 ) ) | a.low ) == 0 ) return a;
6043
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
6044
            aSign = extractFloat128Sign( a );
6045
            switch (status->float_rounding_mode) {
B
bellard 已提交
6046 6047 6048 6049 6050 6051 6052 6053
             case float_round_nearest_even:
                if (    ( aExp == 0x3FFE )
                     && (   extractFloat128Frac0( a )
                          | extractFloat128Frac1( a ) )
                   ) {
                    return packFloat128( aSign, 0x3FFF, 0, 0 );
                }
                break;
6054 6055 6056 6057 6058
            case float_round_ties_away:
                if (aExp == 0x3FFE) {
                    return packFloat128(aSign, 0x3FFF, 0, 0);
                }
                break;
B
bellard 已提交
6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074
             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;
6075
        switch (status->float_rounding_mode) {
6076
        case float_round_nearest_even:
B
bellard 已提交
6077 6078 6079 6080
            z.high += lastBitMask>>1;
            if ( ( ( z.high & roundBitsMask ) | a.low ) == 0 ) {
                z.high &= ~ lastBitMask;
            }
6081
            break;
6082 6083 6084
        case float_round_ties_away:
            z.high += lastBitMask>>1;
            break;
6085 6086 6087 6088
        case float_round_to_zero:
            break;
        case float_round_up:
            if (!extractFloat128Sign(z)) {
B
bellard 已提交
6089 6090 6091
                z.high |= ( a.low != 0 );
                z.high += roundBitsMask;
            }
6092 6093 6094 6095 6096 6097 6098 6099 6100
            break;
        case float_round_down:
            if (extractFloat128Sign(z)) {
                z.high |= (a.low != 0);
                z.high += roundBitsMask;
            }
            break;
        default:
            abort();
B
bellard 已提交
6101 6102 6103 6104
        }
        z.high &= ~ roundBitsMask;
    }
    if ( ( z.low != a.low ) || ( z.high != a.high ) ) {
6105
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118
    }
    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.
*----------------------------------------------------------------------------*/

6119 6120
static float128 addFloat128Sigs(float128 a, float128 b, flag zSign,
                                float_status *status)
B
bellard 已提交
6121
{
6122
    int32_t aExp, bExp, zExp;
6123
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
6124
    int32_t expDiff;
B
bellard 已提交
6125 6126 6127 6128 6129 6130 6131 6132 6133 6134

    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 ) {
P
Peter Maydell 已提交
6135 6136 6137
            if (aSig0 | aSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6138 6139 6140 6141 6142 6143 6144 6145 6146 6147 6148 6149 6150 6151
            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 ) {
P
Peter Maydell 已提交
6152 6153 6154
            if (bSig0 | bSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6155 6156 6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167 6168 6169
            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 ) {
P
Peter Maydell 已提交
6170
                return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6171 6172 6173 6174
            }
            return a;
        }
        add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
6175
        if ( aExp == 0 ) {
6176
            if (status->flush_to_zero) {
6177
                if (zSig0 | zSig1) {
P
Peter Maydell 已提交
6178
                    float_raise(float_flag_output_denormal, status);
6179 6180 6181
                }
                return packFloat128(zSign, 0, 0, 0);
            }
6182 6183
            return packFloat128( zSign, 0, zSig0, zSig1 );
        }
B
bellard 已提交
6184 6185 6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196 6197
        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:
P
Peter Maydell 已提交
6198
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6199 6200 6201 6202 6203 6204 6205 6206 6207 6208 6209

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6210 6211
static float128 subFloat128Sigs(float128 a, float128 b, flag zSign,
                                float_status *status)
B
bellard 已提交
6212
{
6213
    int32_t aExp, bExp, zExp;
6214
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1;
6215
    int32_t expDiff;
B
bellard 已提交
6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229

    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 ) {
P
Peter Maydell 已提交
6230
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6231
        }
P
Peter Maydell 已提交
6232
        float_raise(float_flag_invalid, status);
6233
        return float128_default_nan(status);
B
bellard 已提交
6234 6235 6236 6237 6238 6239 6240 6241 6242
    }
    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;
6243 6244
    return packFloat128(status->float_rounding_mode == float_round_down,
                        0, 0, 0);
B
bellard 已提交
6245 6246
 bExpBigger:
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6247 6248 6249
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6250 6251 6252 6253 6254 6255 6256 6257 6258 6259 6260 6261 6262 6263 6264 6265 6266
        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 ) {
P
Peter Maydell 已提交
6267 6268 6269
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284
        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;
P
Peter Maydell 已提交
6285 6286
    return normalizeRoundAndPackFloat128(zSign, zExp - 14, zSig0, zSig1,
                                         status);
B
bellard 已提交
6287 6288 6289 6290 6291 6292 6293 6294 6295

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6296
float128 float128_add(float128 a, float128 b, float_status *status)
B
bellard 已提交
6297 6298 6299 6300 6301 6302
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
6303
        return addFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6304 6305
    }
    else {
P
Peter Maydell 已提交
6306
        return subFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6307 6308 6309 6310 6311 6312 6313 6314 6315 6316
    }

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6317
float128 float128_sub(float128 a, float128 b, float_status *status)
B
bellard 已提交
6318 6319 6320 6321 6322 6323
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
6324
        return subFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6325 6326
    }
    else {
P
Peter Maydell 已提交
6327
        return addFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6328 6329 6330 6331 6332 6333 6334 6335 6336 6337
    }

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6338
float128 float128_mul(float128 a, float128 b, float_status *status)
B
bellard 已提交
6339 6340
{
    flag aSign, bSign, zSign;
6341
    int32_t aExp, bExp, zExp;
6342
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2, zSig3;
B
bellard 已提交
6343 6344 6345 6346 6347 6348 6349 6350 6351 6352 6353 6354 6355

    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 ) ) ) {
P
Peter Maydell 已提交
6356
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6357 6358 6359 6360 6361
        }
        if ( ( bExp | bSig0 | bSig1 ) == 0 ) goto invalid;
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6362 6363 6364
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6365 6366
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
6367
            float_raise(float_flag_invalid, status);
6368
            return float128_default_nan(status);
B
bellard 已提交
6369 6370 6371 6372 6373 6374 6375 6376 6377 6378 6379 6380 6381 6382 6383 6384 6385 6386 6387 6388 6389 6390
        }
        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;
    }
P
Peter Maydell 已提交
6391
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6392 6393 6394 6395 6396 6397 6398 6399 6400

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6401
float128 float128_div(float128 a, float128 b, float_status *status)
B
bellard 已提交
6402 6403
{
    flag aSign, bSign, zSign;
6404
    int32_t aExp, bExp, zExp;
6405 6406
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417

    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 ) {
P
Peter Maydell 已提交
6418 6419 6420
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6421
        if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6422 6423 6424
            if (bSig0 | bSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6425 6426 6427 6428 6429
            goto invalid;
        }
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6430 6431 6432
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6433 6434 6435 6436 6437 6438
        return packFloat128( zSign, 0, 0, 0 );
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) {
            if ( ( aExp | aSig0 | aSig1 ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
6439
                float_raise(float_flag_invalid, status);
6440
                return float128_default_nan(status);
B
bellard 已提交
6441
            }
P
Peter Maydell 已提交
6442
            float_raise(float_flag_divbyzero, status);
B
bellard 已提交
6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454 6455 6456 6457 6458 6459 6460 6461 6462
            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 );
6463
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
6464 6465 6466 6467 6468 6469 6470
        --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 );
6471
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
6472 6473 6474 6475 6476 6477
            --zSig1;
            add192( rem1, rem2, rem3, 0, bSig0, bSig1, &rem1, &rem2, &rem3 );
        }
        zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 );
    }
    shift128ExtraRightJamming( zSig0, zSig1, 0, 15, &zSig0, &zSig1, &zSig2 );
P
Peter Maydell 已提交
6478
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6479 6480 6481 6482 6483 6484 6485 6486 6487

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6488
float128 float128_rem(float128 a, float128 b, float_status *status)
B
bellard 已提交
6489
{
6490
    flag aSign, zSign;
6491
    int32_t aExp, bExp, expDiff;
6492 6493 6494
    uint64_t aSig0, aSig1, bSig0, bSig1, q, term0, term1, term2;
    uint64_t allZero, alternateASig0, alternateASig1, sigMean1;
    int64_t sigMean0;
B
bellard 已提交
6495 6496 6497 6498 6499 6500 6501 6502 6503 6504 6505

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    bSig1 = extractFloat128Frac1( b );
    bSig0 = extractFloat128Frac0( b );
    bExp = extractFloat128Exp( b );
    if ( aExp == 0x7FFF ) {
        if (    ( aSig0 | aSig1 )
             || ( ( bExp == 0x7FFF ) && ( bSig0 | bSig1 ) ) ) {
P
Peter Maydell 已提交
6506
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6507 6508 6509 6510
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6511 6512 6513
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6514 6515 6516 6517 6518
        return a;
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
6519
            float_raise(float_flag_invalid, status);
6520
            return float128_default_nan(status);
B
bellard 已提交
6521 6522 6523 6524 6525 6526 6527 6528 6529 6530 6531 6532 6533 6534 6535 6536 6537 6538 6539 6540 6541 6542 6543 6544 6545 6546 6547 6548 6549 6550 6551 6552 6553 6554 6555 6556 6557 6558 6559 6560 6561 6562 6563 6564 6565 6566 6567 6568 6569 6570 6571 6572 6573 6574
        }
        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 );
6575
    } while ( 0 <= (int64_t) aSig0 );
B
bellard 已提交
6576
    add128(
6577
        aSig0, aSig1, alternateASig0, alternateASig1, (uint64_t *)&sigMean0, &sigMean1 );
B
bellard 已提交
6578 6579 6580 6581 6582
    if (    ( sigMean0 < 0 )
         || ( ( ( sigMean0 | sigMean1 ) == 0 ) && ( q & 1 ) ) ) {
        aSig0 = alternateASig0;
        aSig1 = alternateASig1;
    }
6583
    zSign = ( (int64_t) aSig0 < 0 );
B
bellard 已提交
6584
    if ( zSign ) sub128( 0, 0, aSig0, aSig1, &aSig0, &aSig1 );
P
Peter Maydell 已提交
6585 6586
    return normalizeRoundAndPackFloat128(aSign ^ zSign, bExp - 4, aSig0, aSig1,
                                         status);
B
bellard 已提交
6587 6588 6589 6590 6591 6592 6593 6594
}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6595
float128 float128_sqrt(float128 a, float_status *status)
B
bellard 已提交
6596 6597
{
    flag aSign;
6598
    int32_t aExp, zExp;
6599 6600
    uint64_t aSig0, aSig1, zSig0, zSig1, zSig2, doubleZSig0;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
6601 6602 6603 6604 6605 6606

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
6607 6608 6609
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, a, status);
        }
B
bellard 已提交
6610 6611 6612 6613 6614 6615
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) return a;
 invalid:
P
Peter Maydell 已提交
6616
        float_raise(float_flag_invalid, status);
6617
        return float128_default_nan(status);
B
bellard 已提交
6618 6619 6620 6621 6622 6623 6624 6625 6626 6627 6628 6629 6630
    }
    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 );
6631
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
6632 6633 6634 6635 6636 6637 6638 6639 6640 6641 6642
        --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 );
6643
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
6644 6645 6646 6647 6648 6649 6650 6651 6652
            --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 );
P
Peter Maydell 已提交
6653
    return roundAndPackFloat128(0, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6654 6655 6656 6657 6658

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
6659 6660
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  Otherwise, the comparison is performed
B
bellard 已提交
6661 6662 6663
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

6664
int float128_eq(float128 a, float128 b, float_status *status)
B
bellard 已提交
6665 6666 6667 6668 6669 6670 6671
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6672
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6673 6674 6675 6676 6677 6678
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
6679
                  && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
6680 6681 6682 6683 6684 6685
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
6686 6687 6688
| or equal to the corresponding value `b', and 0 otherwise.  The invalid
| exception is raised if either operand is a NaN.  The comparison is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
6689 6690
*----------------------------------------------------------------------------*/

6691
int float128_le(float128 a, float128 b, float_status *status)
B
bellard 已提交
6692 6693 6694 6695 6696 6697 6698 6699
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6700
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6701 6702 6703 6704 6705 6706 6707
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6708
            || (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6709 6710 6711 6712 6713 6714 6715 6716 6717 6718
                 == 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
6719 6720 6721
| the corresponding value `b', and 0 otherwise.  The invalid exception is
| raised if either operand is a NaN.  The comparison is performed according
| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
6722 6723
*----------------------------------------------------------------------------*/

6724
int float128_lt(float128 a, float128 b, float_status *status)
B
bellard 已提交
6725 6726 6727 6728 6729 6730 6731 6732
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6733
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6734 6735 6736 6737 6738 6739 6740
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6741
            && (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6742 6743 6744 6745 6746 6747 6748 6749
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

6750 6751
/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot
6752 6753 6754
| be compared, and 0 otherwise.  The invalid exception is raised if either
| operand is a NaN. The comparison is performed according to the IEC/IEEE
| Standard for Binary Floating-Point Arithmetic.
6755 6756
*----------------------------------------------------------------------------*/

6757
int float128_unordered(float128 a, float128 b, float_status *status)
6758 6759 6760 6761 6762 6763
{
    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6764
        float_raise(float_flag_invalid, status);
6765 6766 6767 6768 6769
        return 1;
    }
    return 0;
}

B
bellard 已提交
6770 6771
/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
6772 6773 6774
| the corresponding value `b', and 0 otherwise.  Quiet NaNs do not cause an
| exception.  The comparison is performed according to the IEC/IEEE Standard
| for Binary Floating-Point Arithmetic.
B
bellard 已提交
6775 6776
*----------------------------------------------------------------------------*/

6777
int float128_eq_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6778 6779 6780 6781 6782 6783 6784
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6785 6786
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6787
            float_raise(float_flag_invalid, status);
6788
        }
B
bellard 已提交
6789 6790 6791 6792 6793 6794
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
6795
                  && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
6796 6797 6798 6799 6800 6801 6802 6803 6804 6805 6806
           );

}

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6807
int float128_le_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6808 6809 6810 6811 6812 6813 6814 6815
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6816 6817
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6818
            float_raise(float_flag_invalid, status);
B
bellard 已提交
6819 6820 6821 6822 6823 6824 6825 6826
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6827
            || (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6828 6829 6830 6831 6832 6833 6834 6835 6836 6837 6838 6839 6840 6841 6842
                 == 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.
*----------------------------------------------------------------------------*/

6843
int float128_lt_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6844 6845 6846 6847 6848 6849 6850 6851
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6852 6853
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6854
            float_raise(float_flag_invalid, status);
B
bellard 已提交
6855 6856 6857 6858 6859 6860 6861 6862
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6863
            && (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6864 6865 6866 6867 6868 6869 6870 6871
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

6872 6873 6874 6875 6876 6877 6878
/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot
| be compared, and 0 otherwise.  Quiet NaNs do not cause an exception.  The
| comparison is performed according to the IEC/IEEE Standard for Binary
| Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

6879
int float128_unordered_quiet(float128 a, float128 b, float_status *status)
6880 6881 6882 6883 6884 6885
{
    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6886 6887
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6888
            float_raise(float_flag_invalid, status);
6889 6890 6891 6892 6893 6894
        }
        return 1;
    }
    return 0;
}

6895 6896
static inline int floatx80_compare_internal(floatx80 a, floatx80 b,
                                            int is_quiet, float_status *status)
6897 6898 6899
{
    flag aSign, bSign;

6900 6901 6902 6903
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return float_relation_unordered;
    }
6904 6905 6906 6907 6908
    if (( ( extractFloatx80Exp( a ) == 0x7fff ) &&
          ( extractFloatx80Frac( a )<<1 ) ) ||
        ( ( extractFloatx80Exp( b ) == 0x7fff ) &&
          ( extractFloatx80Frac( b )<<1 ) )) {
        if (!is_quiet ||
6909 6910
            floatx80_is_signaling_nan(a, status) ||
            floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6911
            float_raise(float_flag_invalid, status);
6912 6913 6914 6915 6916 6917 6918 6919 6920 6921 6922 6923 6924 6925 6926 6927 6928 6929 6930 6931 6932 6933 6934
        }
        return float_relation_unordered;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {

        if ( ( ( (uint16_t) ( ( a.high | b.high ) << 1 ) ) == 0) &&
             ( ( a.low | b.low ) == 0 ) ) {
            /* zero case */
            return float_relation_equal;
        } else {
            return 1 - (2 * aSign);
        }
    } else {
        if (a.low == b.low && a.high == b.high) {
            return float_relation_equal;
        } else {
            return 1 - 2 * (aSign ^ ( lt128( a.high, a.low, b.high, b.low ) ));
        }
    }
}

6935
int floatx80_compare(floatx80 a, floatx80 b, float_status *status)
6936
{
P
Peter Maydell 已提交
6937
    return floatx80_compare_internal(a, b, 0, status);
6938 6939
}

6940
int floatx80_compare_quiet(floatx80 a, floatx80 b, float_status *status)
6941
{
P
Peter Maydell 已提交
6942
    return floatx80_compare_internal(a, b, 1, status);
6943 6944
}

6945 6946
static inline int float128_compare_internal(float128 a, float128 b,
                                            int is_quiet, float_status *status)
B
blueswir1 已提交
6947 6948 6949 6950 6951 6952 6953 6954
{
    flag aSign, bSign;

    if (( ( extractFloat128Exp( a ) == 0x7fff ) &&
          ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) ||
        ( ( extractFloat128Exp( b ) == 0x7fff ) &&
          ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )) {
        if (!is_quiet ||
6955 6956
            float128_is_signaling_nan(a, status) ||
            float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6957
            float_raise(float_flag_invalid, status);
B
blueswir1 已提交
6958 6959 6960 6961 6962 6963 6964 6965 6966 6967 6968 6969 6970 6971 6972 6973 6974 6975 6976 6977 6978
        }
        return float_relation_unordered;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        if ( ( ( ( a.high | b.high )<<1 ) | a.low | b.low ) == 0 ) {
            /* zero case */
            return float_relation_equal;
        } else {
            return 1 - (2 * aSign);
        }
    } else {
        if (a.low == b.low && a.high == b.high) {
            return float_relation_equal;
        } else {
            return 1 - 2 * (aSign ^ ( lt128( a.high, a.low, b.high, b.low ) ));
        }
    }
}

6979
int float128_compare(float128 a, float128 b, float_status *status)
B
blueswir1 已提交
6980
{
P
Peter Maydell 已提交
6981
    return float128_compare_internal(a, b, 0, status);
B
blueswir1 已提交
6982 6983
}

6984
int float128_compare_quiet(float128 a, float128 b, float_status *status)
B
blueswir1 已提交
6985
{
P
Peter Maydell 已提交
6986
    return float128_compare_internal(a, b, 1, status);
B
blueswir1 已提交
6987 6988
}

6989
floatx80 floatx80_scalbn(floatx80 a, int n, float_status *status)
P
pbrook 已提交
6990 6991
{
    flag aSign;
6992
    int32_t aExp;
6993
    uint64_t aSig;
P
pbrook 已提交
6994

6995 6996 6997 6998
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
P
pbrook 已提交
6999 7000 7001 7002
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );

7003 7004
    if ( aExp == 0x7FFF ) {
        if ( aSig<<1 ) {
P
Peter Maydell 已提交
7005
            return propagateFloatx80NaN(a, a, status);
7006
        }
P
pbrook 已提交
7007 7008
        return a;
    }
7009

7010 7011 7012 7013 7014 7015
    if (aExp == 0) {
        if (aSig == 0) {
            return a;
        }
        aExp++;
    }
7016

7017 7018 7019 7020 7021 7022
    if (n > 0x10000) {
        n = 0x10000;
    } else if (n < -0x10000) {
        n = -0x10000;
    }

P
pbrook 已提交
7023
    aExp += n;
7024 7025
    return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision,
                                         aSign, aExp, aSig, 0, status);
P
pbrook 已提交
7026 7027
}

7028
float128 float128_scalbn(float128 a, int n, float_status *status)
P
pbrook 已提交
7029 7030
{
    flag aSign;
7031
    int32_t aExp;
7032
    uint64_t aSig0, aSig1;
P
pbrook 已提交
7033 7034 7035 7036 7037 7038

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
7039
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
7040
            return propagateFloat128NaN(a, a, status);
7041
        }
P
pbrook 已提交
7042 7043
        return a;
    }
7044
    if (aExp != 0) {
7045
        aSig0 |= LIT64( 0x0001000000000000 );
7046
    } else if (aSig0 == 0 && aSig1 == 0) {
7047
        return a;
7048 7049 7050
    } else {
        aExp++;
    }
7051

7052 7053 7054 7055 7056 7057
    if (n > 0x10000) {
        n = 0x10000;
    } else if (n < -0x10000) {
        n = -0x10000;
    }

7058 7059
    aExp += n - 1;
    return normalizeRoundAndPackFloat128( aSign, aExp, aSig0, aSig1
P
Peter Maydell 已提交
7060
                                         , status);
P
pbrook 已提交
7061 7062

}