softfloat.c 244.2 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_dnan,
    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 {
#ifdef NO_SIGNALING_NANS
            part.cls = float_class_qnan;
#else
            int64_t msb = part.frac << (parm->frac_shift + 2);
            if ((msb < 0) == status->snan_bit_is_one) {
                part.cls = float_class_snan;
            } else {
                part.cls = float_class_qnan;
            }
#endif
        }
    } 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;
        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_dnan:
        return float16_default_nan(s);
    case float_class_msnan:
        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_dnan:
        return float32_default_nan(s);
    case float_class_msnan:
        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_dnan:
        return float64_default_nan(s);
    case float_class_msnan:
        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) {
            a.cls = float_class_dnan;
        }
        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) {
        a.cls = float_class_dnan;
    } 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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        a.cls = float_class_dnan;
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        return a;
    }
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    switch (which) {
    case 0:
        break;
    case 1:
        a = b;
        break;
    case 2:
        a = c;
        break;
    case 3:
        a.cls = float_class_dnan;
        return a;
    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);
                a.cls = float_class_dnan;
            }
            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);
}

A
Alex Bennée 已提交
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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;
        a.cls = float_class_dnan;
        a.sign = sign;
        return a;
    }
    /* 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);
}

A
Alex Bennée 已提交
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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;
        a.cls = float_class_dnan;
        return a;
    }

    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;
            a.cls = float_class_dnan;
        } else {
            a.cls = float_class_inf;
            a.sign = c.sign ^ sign_flip;
        }
        return a;
    }

    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);
}

A
Alex Bennée 已提交
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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;
        a.cls = float_class_dnan;
        return a;
    }
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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;
    }
A
Alex Bennée 已提交
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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:
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    case float_class_dnan:
    case float_class_msnan:
1355
        s->float_exception_flags = orig_flags | float_flag_invalid;
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        return max;
    case float_class_inf:
1358
        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) {
1371
            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_dnan:
    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
1921 1922 1923 1924 1925 1926 1927 1928 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 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
/*
 * 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;
        a.cls = float_class_dnan;
        return a;
    }
    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
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

2028
static int32_t roundAndPackInt32(flag zSign, uint64_t absZ, float_status *status)
B
bellard 已提交
2029
{
2030
    int8_t roundingMode;
B
bellard 已提交
2031
    flag roundNearestEven;
2032
    int8_t roundIncrement, roundBits;
2033
    int32_t z;
B
bellard 已提交
2034

2035
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2036
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2037 2038
    switch (roundingMode) {
    case float_round_nearest_even:
2039
    case float_round_ties_away:
2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052
        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
2053 2054 2055 2056 2057 2058 2059
    }
    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
2060
        float_raise(float_flag_invalid, status);
2061
        return zSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
2062
    }
2063 2064 2065
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081
    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.
*----------------------------------------------------------------------------*/

2082
static int64_t roundAndPackInt64(flag zSign, uint64_t absZ0, uint64_t absZ1,
2083
                               float_status *status)
B
bellard 已提交
2084
{
2085
    int8_t roundingMode;
B
bellard 已提交
2086
    flag roundNearestEven, increment;
2087
    int64_t z;
B
bellard 已提交
2088

2089
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2090
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2091 2092
    switch (roundingMode) {
    case float_round_nearest_even:
2093
    case float_round_ties_away:
2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106
        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
2107 2108 2109 2110
    }
    if ( increment ) {
        ++absZ0;
        if ( absZ0 == 0 ) goto overflow;
2111
        absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven );
B
bellard 已提交
2112 2113 2114 2115 2116
    }
    z = absZ0;
    if ( zSign ) z = - z;
    if ( z && ( ( z < 0 ) ^ zSign ) ) {
 overflow:
P
Peter Maydell 已提交
2117
        float_raise(float_flag_invalid, status);
B
bellard 已提交
2118
        return
2119
              zSign ? (int64_t) LIT64( 0x8000000000000000 )
B
bellard 已提交
2120 2121
            : LIT64( 0x7FFFFFFFFFFFFFFF );
    }
2122 2123 2124
    if (absZ1) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2125 2126 2127 2128
    return z;

}

T
Tom Musta 已提交
2129 2130 2131 2132 2133 2134 2135 2136 2137 2138
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

2139
static int64_t roundAndPackUint64(flag zSign, uint64_t absZ0,
2140
                                uint64_t absZ1, float_status *status)
T
Tom Musta 已提交
2141
{
2142
    int8_t roundingMode;
T
Tom Musta 已提交
2143 2144
    flag roundNearestEven, increment;

2145
    roundingMode = status->float_rounding_mode;
T
Tom Musta 已提交
2146
    roundNearestEven = (roundingMode == float_round_nearest_even);
2147 2148
    switch (roundingMode) {
    case float_round_nearest_even:
2149
    case float_round_ties_away:
2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
        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
2163 2164 2165 2166
    }
    if (increment) {
        ++absZ0;
        if (absZ0 == 0) {
P
Peter Maydell 已提交
2167
            float_raise(float_flag_invalid, status);
T
Tom Musta 已提交
2168 2169 2170 2171 2172 2173
            return LIT64(0xFFFFFFFFFFFFFFFF);
        }
        absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven);
    }

    if (zSign && absZ0) {
P
Peter Maydell 已提交
2174
        float_raise(float_flag_invalid, status);
T
Tom Musta 已提交
2175 2176 2177 2178
        return 0;
    }

    if (absZ1) {
2179
        status->float_exception_flags |= float_flag_inexact;
T
Tom Musta 已提交
2180 2181 2182 2183
    }
    return absZ0;
}

2184 2185 2186 2187
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
2188
float32 float32_squash_input_denormal(float32 a, float_status *status)
2189
{
2190
    if (status->flush_inputs_to_zero) {
2191
        if (extractFloat32Exp(a) == 0 && extractFloat32Frac(a) != 0) {
P
Peter Maydell 已提交
2192
            float_raise(float_flag_input_denormal, status);
2193 2194 2195 2196 2197 2198
            return make_float32(float32_val(a) & 0x80000000);
        }
    }
    return a;
}

B
bellard 已提交
2199 2200 2201 2202 2203 2204 2205 2206
/*----------------------------------------------------------------------------
| 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
2207
 normalizeFloat32Subnormal(uint32_t aSig, int *zExpPtr, uint32_t *zSigPtr)
B
bellard 已提交
2208
{
2209
    int8_t shiftCount;
B
bellard 已提交
2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238

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

2239
static float32 roundAndPackFloat32(flag zSign, int zExp, uint32_t zSig,
2240
                                   float_status *status)
B
bellard 已提交
2241
{
2242
    int8_t roundingMode;
B
bellard 已提交
2243
    flag roundNearestEven;
2244
    int8_t roundIncrement, roundBits;
B
bellard 已提交
2245 2246
    flag isTiny;

2247
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2248
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2249 2250
    switch (roundingMode) {
    case float_round_nearest_even:
2251
    case float_round_ties_away:
2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265
        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
2266 2267
    }
    roundBits = zSig & 0x7F;
2268
    if ( 0xFD <= (uint16_t) zExp ) {
B
bellard 已提交
2269 2270
        if (    ( 0xFD < zExp )
             || (    ( zExp == 0xFD )
2271
                  && ( (int32_t) ( zSig + roundIncrement ) < 0 ) )
B
bellard 已提交
2272
           ) {
P
Peter Maydell 已提交
2273
            float_raise(float_flag_overflow | float_flag_inexact, status);
P
pbrook 已提交
2274
            return packFloat32( zSign, 0xFF, - ( roundIncrement == 0 ));
B
bellard 已提交
2275 2276
        }
        if ( zExp < 0 ) {
2277
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2278
                float_raise(float_flag_output_denormal, status);
2279 2280
                return packFloat32(zSign, 0, 0);
            }
B
bellard 已提交
2281
            isTiny =
2282 2283
                (status->float_detect_tininess
                 == float_tininess_before_rounding)
B
bellard 已提交
2284 2285 2286 2287 2288
                || ( zExp < -1 )
                || ( zSig + roundIncrement < 0x80000000 );
            shift32RightJamming( zSig, - zExp, &zSig );
            zExp = 0;
            roundBits = zSig & 0x7F;
P
Peter Maydell 已提交
2289 2290 2291
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
B
bellard 已提交
2292 2293
        }
    }
2294 2295 2296
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313
    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
2314
 normalizeRoundAndPackFloat32(flag zSign, int zExp, uint32_t zSig,
2315
                              float_status *status)
B
bellard 已提交
2316
{
2317
    int8_t shiftCount;
B
bellard 已提交
2318 2319

    shiftCount = countLeadingZeros32( zSig ) - 1;
P
Peter Maydell 已提交
2320 2321
    return roundAndPackFloat32(zSign, zExp - shiftCount, zSig<<shiftCount,
                               status);
B
bellard 已提交
2322 2323 2324

}

2325 2326 2327 2328
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
2329
float64 float64_squash_input_denormal(float64 a, float_status *status)
2330
{
2331
    if (status->flush_inputs_to_zero) {
2332
        if (extractFloat64Exp(a) == 0 && extractFloat64Frac(a) != 0) {
P
Peter Maydell 已提交
2333
            float_raise(float_flag_input_denormal, status);
2334 2335 2336 2337 2338 2339
            return make_float64(float64_val(a) & (1ULL << 63));
        }
    }
    return a;
}

B
bellard 已提交
2340 2341 2342 2343 2344 2345 2346 2347
/*----------------------------------------------------------------------------
| 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
2348
 normalizeFloat64Subnormal(uint64_t aSig, int *zExpPtr, uint64_t *zSigPtr)
B
bellard 已提交
2349
{
2350
    int8_t shiftCount;
B
bellard 已提交
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368

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

2369
static inline float64 packFloat64(flag zSign, int zExp, uint64_t zSig)
B
bellard 已提交
2370 2371
{

P
pbrook 已提交
2372
    return make_float64(
2373
        ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<52 ) + zSig);
B
bellard 已提交
2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384

}

/*----------------------------------------------------------------------------
| 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
2385 2386 2387
| 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
2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398
| 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.
*----------------------------------------------------------------------------*/

2399
static float64 roundAndPackFloat64(flag zSign, int zExp, uint64_t zSig,
2400
                                   float_status *status)
B
bellard 已提交
2401
{
2402
    int8_t roundingMode;
B
bellard 已提交
2403
    flag roundNearestEven;
2404
    int roundIncrement, roundBits;
B
bellard 已提交
2405 2406
    flag isTiny;

2407
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2408
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2409 2410
    switch (roundingMode) {
    case float_round_nearest_even:
2411
    case float_round_ties_away:
2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422
        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;
2423 2424 2425
    case float_round_to_odd:
        roundIncrement = (zSig & 0x400) ? 0 : 0x3ff;
        break;
2426 2427
    default:
        abort();
B
bellard 已提交
2428 2429
    }
    roundBits = zSig & 0x3FF;
2430
    if ( 0x7FD <= (uint16_t) zExp ) {
B
bellard 已提交
2431 2432
        if (    ( 0x7FD < zExp )
             || (    ( zExp == 0x7FD )
2433
                  && ( (int64_t) ( zSig + roundIncrement ) < 0 ) )
B
bellard 已提交
2434
           ) {
2435 2436
            bool overflow_to_inf = roundingMode != float_round_to_odd &&
                                   roundIncrement != 0;
P
Peter Maydell 已提交
2437
            float_raise(float_flag_overflow | float_flag_inexact, status);
2438
            return packFloat64(zSign, 0x7FF, -(!overflow_to_inf));
B
bellard 已提交
2439 2440
        }
        if ( zExp < 0 ) {
2441
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2442
                float_raise(float_flag_output_denormal, status);
2443 2444
                return packFloat64(zSign, 0, 0);
            }
B
bellard 已提交
2445
            isTiny =
2446 2447
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2448 2449 2450 2451 2452
                || ( zExp < -1 )
                || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) );
            shift64RightJamming( zSig, - zExp, &zSig );
            zExp = 0;
            roundBits = zSig & 0x3FF;
P
Peter Maydell 已提交
2453 2454 2455
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
2456 2457 2458 2459 2460 2461 2462
            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
2463 2464
        }
    }
2465 2466 2467
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484
    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
2485
 normalizeRoundAndPackFloat64(flag zSign, int zExp, uint64_t zSig,
2486
                              float_status *status)
B
bellard 已提交
2487
{
2488
    int8_t shiftCount;
B
bellard 已提交
2489 2490

    shiftCount = countLeadingZeros64( zSig ) - 1;
P
Peter Maydell 已提交
2491 2492
    return roundAndPackFloat64(zSign, zExp - shiftCount, zSig<<shiftCount,
                               status);
B
bellard 已提交
2493 2494 2495 2496 2497 2498 2499 2500 2501 2502

}

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

2503 2504
void normalizeFloatx80Subnormal(uint64_t aSig, int32_t *zExpPtr,
                                uint64_t *zSigPtr)
B
bellard 已提交
2505
{
2506
    int8_t shiftCount;
B
bellard 已提交
2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536

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

2537 2538 2539
floatx80 roundAndPackFloatx80(int8_t roundingPrecision, flag zSign,
                              int32_t zExp, uint64_t zSig0, uint64_t zSig1,
                              float_status *status)
B
bellard 已提交
2540
{
2541
    int8_t roundingMode;
B
bellard 已提交
2542
    flag roundNearestEven, increment, isTiny;
2543
    int64_t roundIncrement, roundMask, roundBits;
B
bellard 已提交
2544

2545
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559
    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 );
2560 2561
    switch (roundingMode) {
    case float_round_nearest_even:
2562
    case float_round_ties_away:
2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574
        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
2575 2576
    }
    roundBits = zSig0 & roundMask;
2577
    if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) {
B
bellard 已提交
2578 2579 2580 2581 2582 2583
        if (    ( 0x7FFE < zExp )
             || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) )
           ) {
            goto overflow;
        }
        if ( zExp <= 0 ) {
2584
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2585
                float_raise(float_flag_output_denormal, status);
2586 2587
                return packFloatx80(zSign, 0, 0);
            }
B
bellard 已提交
2588
            isTiny =
2589 2590
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2591 2592 2593 2594 2595
                || ( zExp < 0 )
                || ( zSig0 <= zSig0 + roundIncrement );
            shift64RightJamming( zSig0, 1 - zExp, &zSig0 );
            zExp = 0;
            roundBits = zSig0 & roundMask;
P
Peter Maydell 已提交
2596 2597 2598
            if (isTiny && roundBits) {
                float_raise(float_flag_underflow, status);
            }
2599 2600 2601
            if (roundBits) {
                status->float_exception_flags |= float_flag_inexact;
            }
B
bellard 已提交
2602
            zSig0 += roundIncrement;
2603
            if ( (int64_t) zSig0 < 0 ) zExp = 1;
B
bellard 已提交
2604 2605 2606 2607 2608 2609 2610 2611
            roundIncrement = roundMask + 1;
            if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
                roundMask |= roundIncrement;
            }
            zSig0 &= ~ roundMask;
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
2612 2613 2614
    if (roundBits) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627
    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:
2628 2629
    switch (roundingMode) {
    case float_round_nearest_even:
2630
    case float_round_ties_away:
2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643
        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
2644
    }
2645
    if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) {
B
bellard 已提交
2646 2647 2648 2649 2650 2651 2652 2653
        if (    ( 0x7FFE < zExp )
             || (    ( zExp == 0x7FFE )
                  && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) )
                  && increment
                )
           ) {
            roundMask = 0;
 overflow:
P
Peter Maydell 已提交
2654
            float_raise(float_flag_overflow | float_flag_inexact, status);
B
bellard 已提交
2655 2656 2657 2658 2659 2660
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
               ) {
                return packFloatx80( zSign, 0x7FFE, ~ roundMask );
            }
2661 2662 2663
            return packFloatx80(zSign,
                                floatx80_infinity_high,
                                floatx80_infinity_low);
B
bellard 已提交
2664 2665 2666
        }
        if ( zExp <= 0 ) {
            isTiny =
2667 2668
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2669 2670 2671 2672 2673
                || ( zExp < 0 )
                || ! increment
                || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) );
            shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 );
            zExp = 0;
P
Peter Maydell 已提交
2674 2675 2676
            if (isTiny && zSig1) {
                float_raise(float_flag_underflow, status);
            }
2677 2678 2679
            if (zSig1) {
                status->float_exception_flags |= float_flag_inexact;
            }
2680 2681
            switch (roundingMode) {
            case float_round_nearest_even:
2682
            case float_round_ties_away:
2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695
                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
2696 2697 2698 2699
            }
            if ( increment ) {
                ++zSig0;
                zSig0 &=
2700 2701
                    ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven );
                if ( (int64_t) zSig0 < 0 ) zExp = 1;
B
bellard 已提交
2702 2703 2704 2705
            }
            return packFloatx80( zSign, zExp, zSig0 );
        }
    }
2706 2707 2708
    if (zSig1) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2709 2710 2711 2712 2713 2714 2715
    if ( increment ) {
        ++zSig0;
        if ( zSig0 == 0 ) {
            ++zExp;
            zSig0 = LIT64( 0x8000000000000000 );
        }
        else {
2716
            zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven );
B
bellard 已提交
2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734
        }
    }
    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.
*----------------------------------------------------------------------------*/

2735 2736 2737 2738
floatx80 normalizeRoundAndPackFloatx80(int8_t roundingPrecision,
                                       flag zSign, int32_t zExp,
                                       uint64_t zSig0, uint64_t zSig1,
                                       float_status *status)
B
bellard 已提交
2739
{
2740
    int8_t shiftCount;
B
bellard 已提交
2741 2742 2743 2744 2745 2746 2747 2748 2749

    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
2750 2751
    return roundAndPackFloatx80(roundingPrecision, zSign, zExp,
                                zSig0, zSig1, status);
B
bellard 已提交
2752 2753 2754 2755 2756 2757 2758 2759

}

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

2760
static inline uint64_t extractFloat128Frac1( float128 a )
B
bellard 已提交
2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771
{

    return a.low;

}

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

2772
static inline uint64_t extractFloat128Frac0( float128 a )
B
bellard 已提交
2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783
{

    return a.high & LIT64( 0x0000FFFFFFFFFFFF );

}

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

2784
static inline int32_t extractFloat128Exp( float128 a )
B
bellard 已提交
2785 2786 2787 2788 2789 2790 2791 2792 2793 2794
{

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

}

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

2795
static inline flag extractFloat128Sign( float128 a )
B
bellard 已提交
2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813
{

    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(
2814 2815
     uint64_t aSig0,
     uint64_t aSig1,
2816
     int32_t *zExpPtr,
2817 2818
     uint64_t *zSig0Ptr,
     uint64_t *zSig1Ptr
B
bellard 已提交
2819 2820
 )
{
2821
    int8_t shiftCount;
B
bellard 已提交
2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855

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

2856
static inline float128
2857
 packFloat128( flag zSign, int32_t zExp, uint64_t zSig0, uint64_t zSig1 )
B
bellard 已提交
2858 2859 2860 2861
{
    float128 z;

    z.low = zSig1;
2862
    z.high = ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<48 ) + zSig0;
B
bellard 已提交
2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887
    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.
*----------------------------------------------------------------------------*/

2888
static float128 roundAndPackFloat128(flag zSign, int32_t zExp,
2889 2890
                                     uint64_t zSig0, uint64_t zSig1,
                                     uint64_t zSig2, float_status *status)
B
bellard 已提交
2891
{
2892
    int8_t roundingMode;
B
bellard 已提交
2893 2894
    flag roundNearestEven, increment, isTiny;

2895
    roundingMode = status->float_rounding_mode;
B
bellard 已提交
2896
    roundNearestEven = ( roundingMode == float_round_nearest_even );
2897 2898
    switch (roundingMode) {
    case float_round_nearest_even:
2899
    case float_round_ties_away:
2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910
        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;
2911 2912 2913
    case float_round_to_odd:
        increment = !(zSig1 & 0x1) && zSig2;
        break;
2914 2915
    default:
        abort();
B
bellard 已提交
2916
    }
2917
    if ( 0x7FFD <= (uint32_t) zExp ) {
B
bellard 已提交
2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928
        if (    ( 0x7FFD < zExp )
             || (    ( zExp == 0x7FFD )
                  && eq128(
                         LIT64( 0x0001FFFFFFFFFFFF ),
                         LIT64( 0xFFFFFFFFFFFFFFFF ),
                         zSig0,
                         zSig1
                     )
                  && increment
                )
           ) {
P
Peter Maydell 已提交
2929
            float_raise(float_flag_overflow | float_flag_inexact, status);
B
bellard 已提交
2930 2931 2932
            if (    ( roundingMode == float_round_to_zero )
                 || ( zSign && ( roundingMode == float_round_up ) )
                 || ( ! zSign && ( roundingMode == float_round_down ) )
2933
                 || (roundingMode == float_round_to_odd)
B
bellard 已提交
2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945
               ) {
                return
                    packFloat128(
                        zSign,
                        0x7FFE,
                        LIT64( 0x0000FFFFFFFFFFFF ),
                        LIT64( 0xFFFFFFFFFFFFFFFF )
                    );
            }
            return packFloat128( zSign, 0x7FFF, 0, 0 );
        }
        if ( zExp < 0 ) {
2946
            if (status->flush_to_zero) {
P
Peter Maydell 已提交
2947
                float_raise(float_flag_output_denormal, status);
2948 2949
                return packFloat128(zSign, 0, 0, 0);
            }
B
bellard 已提交
2950
            isTiny =
2951 2952
                   (status->float_detect_tininess
                    == float_tininess_before_rounding)
B
bellard 已提交
2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963
                || ( 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
2964 2965 2966
            if (isTiny && zSig2) {
                float_raise(float_flag_underflow, status);
            }
2967 2968
            switch (roundingMode) {
            case float_round_nearest_even:
2969
            case float_round_ties_away:
2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980
                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;
2981 2982 2983
            case float_round_to_odd:
                increment = !(zSig1 & 0x1) && zSig2;
                break;
2984 2985
            default:
                abort();
B
bellard 已提交
2986 2987 2988
            }
        }
    }
2989 2990 2991
    if (zSig2) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012
    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.
*----------------------------------------------------------------------------*/

3013
static float128 normalizeRoundAndPackFloat128(flag zSign, int32_t zExp,
3014 3015
                                              uint64_t zSig0, uint64_t zSig1,
                                              float_status *status)
B
bellard 已提交
3016
{
3017
    int8_t shiftCount;
3018
    uint64_t zSig2;
B
bellard 已提交
3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034

    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
3035
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046

}


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

3047
floatx80 int32_to_floatx80(int32_t a, float_status *status)
B
bellard 已提交
3048 3049
{
    flag zSign;
3050
    uint32_t absA;
3051
    int8_t shiftCount;
3052
    uint64_t zSig;
B
bellard 已提交
3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068

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

3069
float128 int32_to_float128(int32_t a, float_status *status)
B
bellard 已提交
3070 3071
{
    flag zSign;
3072
    uint32_t absA;
3073
    int8_t shiftCount;
3074
    uint64_t zSig0;
B
bellard 已提交
3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091

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

3092
floatx80 int64_to_floatx80(int64_t a, float_status *status)
B
bellard 已提交
3093 3094
{
    flag zSign;
3095
    uint64_t absA;
3096
    int8_t shiftCount;
B
bellard 已提交
3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111

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

3112
float128 int64_to_float128(int64_t a, float_status *status)
B
bellard 已提交
3113 3114
{
    flag zSign;
3115
    uint64_t absA;
3116
    int8_t shiftCount;
3117
    int32_t zExp;
3118
    uint64_t zSig0, zSig1;
B
bellard 已提交
3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138

    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 );

}

3139 3140 3141 3142 3143 3144
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3145
float128 uint64_to_float128(uint64_t a, float_status *status)
3146 3147 3148 3149
{
    if (a == 0) {
        return float128_zero;
    }
3150
    return normalizeRoundAndPackFloat128(0, 0x406E, 0, a, status);
3151 3152
}

B
bellard 已提交
3153 3154 3155 3156 3157 3158 3159 3160 3161 3162



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

3163
float64 float32_to_float64(float32 a, float_status *status)
B
bellard 已提交
3164 3165
{
    flag aSign;
3166
    int aExp;
3167
    uint32_t aSig;
P
Peter Maydell 已提交
3168
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3169 3170 3171 3172 3173

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3174 3175 3176
        if (aSig) {
            return commonNaNToFloat64(float32ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3177 3178 3179 3180 3181 3182 3183
        return packFloat64( aSign, 0x7FF, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat64( aSign, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
3184
    return packFloat64( aSign, aExp + 0x380, ( (uint64_t) aSig )<<29 );
B
bellard 已提交
3185 3186 3187 3188 3189 3190 3191 3192 3193 3194

}

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

3195
floatx80 float32_to_floatx80(float32 a, float_status *status)
B
bellard 已提交
3196 3197
{
    flag aSign;
3198
    int aExp;
3199
    uint32_t aSig;
B
bellard 已提交
3200

P
Peter Maydell 已提交
3201
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3202 3203 3204 3205
    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3206 3207 3208
        if (aSig) {
            return commonNaNToFloatx80(float32ToCommonNaN(a, status), status);
        }
3209 3210 3211
        return packFloatx80(aSign,
                            floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
3212 3213 3214 3215 3216 3217
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
    }
    aSig |= 0x00800000;
3218
    return packFloatx80( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<40 );
B
bellard 已提交
3219 3220 3221 3222 3223 3224 3225 3226 3227 3228

}

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

3229
float128 float32_to_float128(float32 a, float_status *status)
B
bellard 已提交
3230 3231
{
    flag aSign;
3232
    int aExp;
3233
    uint32_t aSig;
B
bellard 已提交
3234

P
Peter Maydell 已提交
3235
    a = float32_squash_input_denormal(a, status);
B
bellard 已提交
3236 3237 3238 3239
    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3240 3241 3242
        if (aSig) {
            return commonNaNToFloat128(float32ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3243 3244 3245 3246 3247 3248 3249
        return packFloat128( aSign, 0x7FFF, 0, 0 );
    }
    if ( aExp == 0 ) {
        if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 );
        normalizeFloat32Subnormal( aSig, &aExp, &aSig );
        --aExp;
    }
3250
    return packFloat128( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<25, 0 );
B
bellard 已提交
3251 3252 3253 3254 3255 3256 3257 3258 3259

}

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

3260
float32 float32_rem(float32 a, float32 b, float_status *status)
B
bellard 已提交
3261
{
3262
    flag aSign, zSign;
3263
    int aExp, bExp, expDiff;
3264 3265 3266 3267 3268
    uint32_t aSig, bSig;
    uint32_t q;
    uint64_t aSig64, bSig64, q64;
    uint32_t alternateASig;
    int32_t sigMean;
P
Peter Maydell 已提交
3269 3270
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3271 3272 3273 3274 3275 3276 3277 3278

    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
3279
            return propagateFloat32NaN(a, b, status);
B
bellard 已提交
3280
        }
P
Peter Maydell 已提交
3281
        float_raise(float_flag_invalid, status);
3282
        return float32_default_nan(status);
B
bellard 已提交
3283 3284
    }
    if ( bExp == 0xFF ) {
P
Peter Maydell 已提交
3285 3286 3287
        if (bSig) {
            return propagateFloat32NaN(a, b, status);
        }
B
bellard 已提交
3288 3289 3290 3291
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
P
Peter Maydell 已提交
3292
            float_raise(float_flag_invalid, status);
3293
            return float32_default_nan(status);
B
bellard 已提交
3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313
        }
        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 ) {
3314
            q = ( ( (uint64_t) aSig )<<32 ) / bSig;
B
bellard 已提交
3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325
            q >>= 32 - expDiff;
            bSig >>= 2;
            aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q;
        }
        else {
            aSig >>= 2;
            bSig >>= 2;
        }
    }
    else {
        if ( bSig <= aSig ) aSig -= bSig;
3326 3327
        aSig64 = ( (uint64_t) aSig )<<40;
        bSig64 = ( (uint64_t) bSig )<<40;
B
bellard 已提交
3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345
        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;
3346
    } while ( 0 <= (int32_t) aSig );
B
bellard 已提交
3347 3348 3349 3350
    sigMean = aSig + alternateASig;
    if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
        aSig = alternateASig;
    }
3351
    zSign = ( (int32_t) aSig < 0 );
B
bellard 已提交
3352
    if ( zSign ) aSig = - aSig;
P
Peter Maydell 已提交
3353
    return normalizeRoundAndPackFloat32(aSign ^ zSign, bExp, aSig, status);
B
bellard 已提交
3354 3355
}

3356

B
bellard 已提交
3357

A
Aurelien Jarno 已提交
3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377
/*----------------------------------------------------------------------------
| 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] =
{
3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392
    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
3393 3394
};

3395
float32 float32_exp2(float32 a, float_status *status)
A
Aurelien Jarno 已提交
3396 3397
{
    flag aSign;
3398
    int aExp;
3399
    uint32_t aSig;
A
Aurelien Jarno 已提交
3400 3401
    float64 r, x, xn;
    int i;
P
Peter Maydell 已提交
3402
    a = float32_squash_input_denormal(a, status);
A
Aurelien Jarno 已提交
3403 3404 3405 3406 3407 3408

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

    if ( aExp == 0xFF) {
P
Peter Maydell 已提交
3409 3410 3411
        if (aSig) {
            return propagateFloat32NaN(a, float32_zero, status);
        }
A
Aurelien Jarno 已提交
3412 3413 3414 3415 3416 3417
        return (aSign) ? float32_zero : a;
    }
    if (aExp == 0) {
        if (aSig == 0) return float32_one;
    }

P
Peter Maydell 已提交
3418
    float_raise(float_flag_inexact, status);
A
Aurelien Jarno 已提交
3419 3420 3421 3422

    /* ******************************* */
    /* using float64 for approximation */
    /* ******************************* */
P
Peter Maydell 已提交
3423 3424
    x = float32_to_float64(a, status);
    x = float64_mul(x, float64_ln2, status);
A
Aurelien Jarno 已提交
3425 3426 3427 3428 3429 3430

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

P
Peter Maydell 已提交
3431 3432
        f = float64_mul(xn, float32_exp2_coefficients[i], status);
        r = float64_add(r, f, status);
A
Aurelien Jarno 已提交
3433

P
Peter Maydell 已提交
3434
        xn = float64_mul(xn, x, status);
A
Aurelien Jarno 已提交
3435 3436 3437 3438 3439
    }

    return float64_to_float32(r, status);
}

3440 3441 3442 3443 3444
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
3445
float32 float32_log2(float32 a, float_status *status)
3446 3447
{
    flag aSign, zSign;
3448
    int aExp;
3449
    uint32_t aSig, zSig, i;
3450

P
Peter Maydell 已提交
3451
    a = float32_squash_input_denormal(a, status);
3452 3453 3454 3455 3456 3457 3458 3459 3460
    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
3461
        float_raise(float_flag_invalid, status);
3462
        return float32_default_nan(status);
3463 3464
    }
    if ( aExp == 0xFF ) {
P
Peter Maydell 已提交
3465 3466 3467
        if (aSig) {
            return propagateFloat32NaN(a, float32_zero, status);
        }
3468 3469 3470 3471 3472 3473 3474 3475 3476
        return a;
    }

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

    for (i = 1 << 22; i > 0; i >>= 1) {
3477
        aSig = ( (uint64_t)aSig * aSig ) >> 23;
3478 3479 3480 3481 3482 3483 3484 3485 3486
        if ( aSig & 0x01000000 ) {
            aSig >>= 1;
            zSig |= i;
        }
    }

    if ( zSign )
        zSig = -zSig;

P
Peter Maydell 已提交
3487
    return normalizeRoundAndPackFloat32(zSign, 0x85, zSig, status);
3488 3489
}

B
bellard 已提交
3490 3491
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is equal to
3492 3493
| 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
3494 3495 3496
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

3497
int float32_eq(float32 a, float32 b, float_status *status)
B
bellard 已提交
3498
{
3499
    uint32_t av, bv;
P
Peter Maydell 已提交
3500 3501
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3502 3503 3504 3505

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3506
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3507 3508
        return 0;
    }
3509 3510 3511
    av = float32_val(a);
    bv = float32_val(b);
    return ( av == bv ) || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
3512 3513 3514 3515
}

/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is less than
3516 3517 3518
| 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
3519 3520
*----------------------------------------------------------------------------*/

3521
int float32_le(float32 a, float32 b, float_status *status)
B
bellard 已提交
3522 3523
{
    flag aSign, bSign;
3524
    uint32_t av, bv;
P
Peter Maydell 已提交
3525 3526
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3527 3528 3529 3530

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3531
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3532 3533 3534 3535
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3536 3537
    av = float32_val(a);
    bv = float32_val(b);
3538
    if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
3539
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
3540 3541 3542 3543 3544

}

/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is less than
3545 3546 3547
| 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
3548 3549
*----------------------------------------------------------------------------*/

3550
int float32_lt(float32 a, float32 b, float_status *status)
B
bellard 已提交
3551 3552
{
    flag aSign, bSign;
3553
    uint32_t av, bv;
P
Peter Maydell 已提交
3554 3555
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3556 3557 3558 3559

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3560
        float_raise(float_flag_invalid, status);
B
bellard 已提交
3561 3562 3563 3564
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3565 3566
    av = float32_val(a);
    bv = float32_val(b);
3567
    if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
3568
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
3569 3570 3571

}

3572 3573
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point values `a' and `b' cannot
3574 3575 3576
| 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.
3577 3578
*----------------------------------------------------------------------------*/

3579
int float32_unordered(float32 a, float32 b, float_status *status)
3580
{
P
Peter Maydell 已提交
3581 3582
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
3583 3584 3585 3586

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
P
Peter Maydell 已提交
3587
        float_raise(float_flag_invalid, status);
3588 3589 3590 3591
        return 1;
    }
    return 0;
}
3592

B
bellard 已提交
3593 3594
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is equal to
3595 3596 3597
| 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
3598 3599
*----------------------------------------------------------------------------*/

3600
int float32_eq_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3601
{
P
Peter Maydell 已提交
3602 3603
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3604 3605 3606 3607

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
3608 3609
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
3610
            float_raise(float_flag_invalid, status);
3611
        }
B
bellard 已提交
3612 3613
        return 0;
    }
3614 3615
    return ( float32_val(a) == float32_val(b) ) ||
            ( (uint32_t) ( ( float32_val(a) | float32_val(b) )<<1 ) == 0 );
B
bellard 已提交
3616 3617 3618 3619 3620 3621 3622 3623 3624
}

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

3625
int float32_le_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3626 3627
{
    flag aSign, bSign;
3628
    uint32_t av, bv;
P
Peter Maydell 已提交
3629 3630
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3631 3632 3633 3634

    if (    ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
         || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
       ) {
3635 3636
        if (float32_is_signaling_nan(a, status)
         || float32_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
3637
            float_raise(float_flag_invalid, status);
B
bellard 已提交
3638 3639 3640 3641 3642
        }
        return 0;
    }
    aSign = extractFloat32Sign( a );
    bSign = extractFloat32Sign( b );
P
pbrook 已提交
3643 3644
    av = float32_val(a);
    bv = float32_val(b);
3645
    if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
3646
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
3647 3648 3649 3650 3651 3652 3653

}

/*----------------------------------------------------------------------------
| 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
3654
| Standard for Binary Floating-Point Arithmetic.
B
bellard 已提交
3655 3656
*----------------------------------------------------------------------------*/

3657
int float32_lt_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3658
{
3659 3660 3661 3662
    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
3663

3664 3665 3666 3667 3668
    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
3669
            float_raise(float_flag_invalid, status);
B
bellard 已提交
3670
        }
3671
        return 0;
B
bellard 已提交
3672
    }
3673 3674 3675 3676 3677 3678
    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
3679 3680 3681 3682

}

/*----------------------------------------------------------------------------
3683 3684 3685 3686
| 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
3687 3688
*----------------------------------------------------------------------------*/

3689
int float32_unordered_quiet(float32 a, float32 b, float_status *status)
B
bellard 已提交
3690
{
3691 3692
    a = float32_squash_input_denormal(a, status);
    b = float32_squash_input_denormal(b, status);
B
bellard 已提交
3693

3694 3695 3696 3697 3698 3699
    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
3700
        }
3701
        return 1;
B
bellard 已提交
3702
    }
3703
    return 0;
B
bellard 已提交
3704 3705
}

3706

B
bellard 已提交
3707 3708 3709 3710 3711 3712 3713
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3714
float32 float64_to_float32(float64 a, float_status *status)
B
bellard 已提交
3715 3716
{
    flag aSign;
3717
    int aExp;
3718 3719
    uint64_t aSig;
    uint32_t zSig;
P
Peter Maydell 已提交
3720
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
3721 3722 3723 3724 3725

    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
3726 3727 3728
        if (aSig) {
            return commonNaNToFloat32(float64ToCommonNaN(a, status), status);
        }
B
bellard 已提交
3729 3730 3731 3732 3733 3734 3735 3736
        return packFloat32( aSign, 0xFF, 0 );
    }
    shift64RightJamming( aSig, 22, &aSig );
    zSig = aSig;
    if ( aExp || zSig ) {
        zSig |= 0x40000000;
        aExp -= 0x381;
    }
P
Peter Maydell 已提交
3737
    return roundAndPackFloat32(aSign, aExp, zSig, status);
B
bellard 已提交
3738 3739 3740

}

P
Paul Brook 已提交
3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751

/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
3752
static float16 packFloat16(flag zSign, int zExp, uint16_t zSig)
P
Paul Brook 已提交
3753
{
3754
    return make_float16(
3755
        (((uint32_t)zSign) << 15) + (((uint32_t)zExp) << 10) + zSig);
P
Paul Brook 已提交
3756 3757
}

3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

3786
static float16 roundAndPackFloat16(flag zSign, int zExp,
3787 3788
                                   uint32_t zSig, flag ieee,
                                   float_status *status)
3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809
{
    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;
    }

3810
    switch (status->float_rounding_mode) {
3811 3812 3813 3814 3815 3816
    case float_round_nearest_even:
        increment = (mask + 1) >> 1;
        if ((zSig & mask) == increment) {
            increment = zSig & (increment << 1);
        }
        break;
3817 3818 3819
    case float_round_ties_away:
        increment = (mask + 1) >> 1;
        break;
3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834
    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
3835
            float_raise(float_flag_overflow | float_flag_inexact, status);
3836 3837
            return packFloat16(zSign, 0x1f, 0);
        } else {
P
Peter Maydell 已提交
3838
            float_raise(float_flag_invalid, status);
3839 3840 3841 3842 3843 3844 3845
            return packFloat16(zSign, 0x1f, 0x3ff);
        }
    }

    if (zExp < 0) {
        /* Note that flush-to-zero does not affect half-precision results */
        is_tiny =
3846
            (status->float_detect_tininess == float_tininess_before_rounding)
3847 3848 3849 3850
            || (zExp < -1)
            || (!rounding_bumps_exp);
    }
    if (zSig & mask) {
P
Peter Maydell 已提交
3851
        float_raise(float_flag_inexact, status);
3852
        if (is_tiny) {
P
Peter Maydell 已提交
3853
            float_raise(float_flag_underflow, status);
3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872
        }
    }

    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);
}

3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887
/*----------------------------------------------------------------------------
| 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;
}

3888
static void normalizeFloat16Subnormal(uint32_t aSig, int *zExpPtr,
3889 3890 3891 3892 3893 3894 3895
                                      uint32_t *zSigPtr)
{
    int8_t shiftCount = countLeadingZeros32(aSig) - 21;
    *zSigPtr = aSig << shiftCount;
    *zExpPtr = 1 - shiftCount;
}

P
Paul Brook 已提交
3896 3897
/* Half precision floats come in two formats: standard IEEE and "ARM" format.
   The latter gains extra exponent range by omitting the NaN/Inf encodings.  */
3898

3899
float32 float16_to_float32(float16 a, flag ieee, float_status *status)
P
Paul Brook 已提交
3900 3901
{
    flag aSign;
3902
    int aExp;
3903
    uint32_t aSig;
P
Paul Brook 已提交
3904

3905 3906 3907
    aSign = extractFloat16Sign(a);
    aExp = extractFloat16Exp(a);
    aSig = extractFloat16Frac(a);
P
Paul Brook 已提交
3908 3909 3910

    if (aExp == 0x1f && ieee) {
        if (aSig) {
P
Peter Maydell 已提交
3911
            return commonNaNToFloat32(float16ToCommonNaN(a, status), status);
P
Paul Brook 已提交
3912
        }
3913
        return packFloat32(aSign, 0xff, 0);
P
Paul Brook 已提交
3914 3915 3916 3917 3918 3919
    }
    if (aExp == 0) {
        if (aSig == 0) {
            return packFloat32(aSign, 0, 0);
        }

3920 3921
        normalizeFloat16Subnormal(aSig, &aExp, &aSig);
        aExp--;
P
Paul Brook 已提交
3922 3923 3924 3925
    }
    return packFloat32( aSign, aExp + 0x70, aSig << 13);
}

3926
float16 float32_to_float16(float32 a, flag ieee, float_status *status)
P
Paul Brook 已提交
3927 3928
{
    flag aSign;
3929
    int aExp;
3930
    uint32_t aSig;
3931

P
Peter Maydell 已提交
3932
    a = float32_squash_input_denormal(a, status);
P
Paul Brook 已提交
3933 3934 3935 3936 3937 3938

    aSig = extractFloat32Frac( a );
    aExp = extractFloat32Exp( a );
    aSign = extractFloat32Sign( a );
    if ( aExp == 0xFF ) {
        if (aSig) {
3939 3940
            /* Input is a NaN */
            if (!ieee) {
P
Peter Maydell 已提交
3941
                float_raise(float_flag_invalid, status);
3942 3943
                return packFloat16(aSign, 0, 0);
            }
3944
            return commonNaNToFloat16(
P
Peter Maydell 已提交
3945
                float32ToCommonNaN(a, status), status);
P
Paul Brook 已提交
3946
        }
3947 3948
        /* Infinity */
        if (!ieee) {
P
Peter Maydell 已提交
3949
            float_raise(float_flag_invalid, status);
3950 3951 3952
            return packFloat16(aSign, 0x1f, 0x3ff);
        }
        return packFloat16(aSign, 0x1f, 0);
P
Paul Brook 已提交
3953
    }
3954
    if (aExp == 0 && aSig == 0) {
P
Paul Brook 已提交
3955 3956
        return packFloat16(aSign, 0, 0);
    }
3957 3958 3959 3960 3961 3962 3963
    /* 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
3964
    aSig |= 0x00800000;
3965
    aExp -= 0x71;
P
Paul Brook 已提交
3966

P
Peter Maydell 已提交
3967
    return roundAndPackFloat16(aSign, aExp, aSig, ieee, status);
P
Paul Brook 已提交
3968 3969
}

3970
float64 float16_to_float64(float16 a, flag ieee, float_status *status)
3971 3972
{
    flag aSign;
3973
    int aExp;
3974 3975 3976 3977 3978 3979 3980 3981 3982
    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
3983
                float16ToCommonNaN(a, status), status);
3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997
        }
        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);
}

3998
float16 float64_to_float16(float64 a, flag ieee, float_status *status)
3999 4000
{
    flag aSign;
4001
    int aExp;
4002 4003 4004
    uint64_t aSig;
    uint32_t zSig;

P
Peter Maydell 已提交
4005
    a = float64_squash_input_denormal(a, status);
4006 4007 4008 4009 4010 4011 4012 4013

    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
4014
                float_raise(float_flag_invalid, status);
4015 4016 4017
                return packFloat16(aSign, 0, 0);
            }
            return commonNaNToFloat16(
P
Peter Maydell 已提交
4018
                float64ToCommonNaN(a, status), status);
4019 4020 4021
        }
        /* Infinity */
        if (!ieee) {
P
Peter Maydell 已提交
4022
            float_raise(float_flag_invalid, status);
4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041
            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
4042
    return roundAndPackFloat16(aSign, aExp, zSig, ieee, status);
4043 4044
}

B
bellard 已提交
4045 4046 4047 4048 4049 4050 4051
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4052
floatx80 float64_to_floatx80(float64 a, float_status *status)
B
bellard 已提交
4053 4054
{
    flag aSign;
4055
    int aExp;
4056
    uint64_t aSig;
B
bellard 已提交
4057

P
Peter Maydell 已提交
4058
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
4059 4060 4061 4062
    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4063 4064 4065
        if (aSig) {
            return commonNaNToFloatx80(float64ToCommonNaN(a, status), status);
        }
4066 4067 4068
        return packFloatx80(aSign,
                            floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086
    }
    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.
*----------------------------------------------------------------------------*/

4087
float128 float64_to_float128(float64 a, float_status *status)
B
bellard 已提交
4088 4089
{
    flag aSign;
4090
    int aExp;
4091
    uint64_t aSig, zSig0, zSig1;
B
bellard 已提交
4092

P
Peter Maydell 已提交
4093
    a = float64_squash_input_denormal(a, status);
B
bellard 已提交
4094 4095 4096 4097
    aSig = extractFloat64Frac( a );
    aExp = extractFloat64Exp( a );
    aSign = extractFloat64Sign( a );
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4098 4099 4100
        if (aSig) {
            return commonNaNToFloat128(float64ToCommonNaN(a, status), status);
        }
B
bellard 已提交
4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119
        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.
*----------------------------------------------------------------------------*/

4120
float64 float64_rem(float64 a, float64 b, float_status *status)
B
bellard 已提交
4121
{
4122
    flag aSign, zSign;
4123
    int aExp, bExp, expDiff;
4124 4125 4126
    uint64_t aSig, bSig;
    uint64_t q, alternateASig;
    int64_t sigMean;
B
bellard 已提交
4127

P
Peter Maydell 已提交
4128 4129
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4130 4131 4132 4133 4134 4135 4136
    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
4137
            return propagateFloat64NaN(a, b, status);
B
bellard 已提交
4138
        }
P
Peter Maydell 已提交
4139
        float_raise(float_flag_invalid, status);
4140
        return float64_default_nan(status);
B
bellard 已提交
4141 4142
    }
    if ( bExp == 0x7FF ) {
P
Peter Maydell 已提交
4143 4144 4145
        if (bSig) {
            return propagateFloat64NaN(a, b, status);
        }
B
bellard 已提交
4146 4147 4148 4149
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
P
Peter Maydell 已提交
4150
            float_raise(float_flag_invalid, status);
4151
            return float64_default_nan(status);
B
bellard 已提交
4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190
        }
        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;
4191
    } while ( 0 <= (int64_t) aSig );
B
bellard 已提交
4192 4193 4194 4195
    sigMean = aSig + alternateASig;
    if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
        aSig = alternateASig;
    }
4196
    zSign = ( (int64_t) aSig < 0 );
B
bellard 已提交
4197
    if ( zSign ) aSig = - aSig;
P
Peter Maydell 已提交
4198
    return normalizeRoundAndPackFloat64(aSign ^ zSign, bExp, aSig, status);
B
bellard 已提交
4199 4200 4201

}

4202 4203 4204 4205 4206
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
4207
float64 float64_log2(float64 a, float_status *status)
4208 4209
{
    flag aSign, zSign;
4210
    int aExp;
4211
    uint64_t aSig, aSig0, aSig1, zSig, i;
P
Peter Maydell 已提交
4212
    a = float64_squash_input_denormal(a, status);
4213 4214 4215 4216 4217 4218 4219 4220 4221 4222

    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
4223
        float_raise(float_flag_invalid, status);
4224
        return float64_default_nan(status);
4225 4226
    }
    if ( aExp == 0x7FF ) {
P
Peter Maydell 已提交
4227 4228 4229
        if (aSig) {
            return propagateFloat64NaN(a, float64_zero, status);
        }
4230 4231 4232 4233 4234 4235
        return a;
    }

    aExp -= 0x3FF;
    aSig |= LIT64( 0x0010000000000000 );
    zSign = aExp < 0;
4236
    zSig = (uint64_t)aExp << 52;
4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247
    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
4248
    return normalizeRoundAndPackFloat64(zSign, 0x408, zSig, status);
4249 4250
}

B
bellard 已提交
4251 4252
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is equal to the
4253 4254
| 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
4255 4256 4257
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

4258
int float64_eq(float64 a, float64 b, float_status *status)
B
bellard 已提交
4259
{
4260
    uint64_t av, bv;
P
Peter Maydell 已提交
4261 4262
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4263 4264 4265 4266

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4267
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4268 4269
        return 0;
    }
P
pbrook 已提交
4270
    av = float64_val(a);
P
pbrook 已提交
4271
    bv = float64_val(b);
4272
    return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
4273 4274 4275 4276 4277

}

/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is less than or
4278 4279 4280
| 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
4281 4282
*----------------------------------------------------------------------------*/

4283
int float64_le(float64 a, float64 b, float_status *status)
B
bellard 已提交
4284 4285
{
    flag aSign, bSign;
4286
    uint64_t av, bv;
P
Peter Maydell 已提交
4287 4288
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4289 4290 4291 4292

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4293
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4294 4295 4296 4297
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4298
    av = float64_val(a);
P
pbrook 已提交
4299
    bv = float64_val(b);
4300
    if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
4301
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
4302 4303 4304 4305 4306

}

/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is less than
4307 4308 4309
| 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
4310 4311
*----------------------------------------------------------------------------*/

4312
int float64_lt(float64 a, float64 b, float_status *status)
B
bellard 已提交
4313 4314
{
    flag aSign, bSign;
4315
    uint64_t av, bv;
B
bellard 已提交
4316

P
Peter Maydell 已提交
4317 4318
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4319 4320 4321
    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4322
        float_raise(float_flag_invalid, status);
B
bellard 已提交
4323 4324 4325 4326
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4327
    av = float64_val(a);
P
pbrook 已提交
4328
    bv = float64_val(b);
4329
    if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
4330
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
4331 4332 4333

}

4334 4335
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point values `a' and `b' cannot
4336 4337 4338
| 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.
4339 4340
*----------------------------------------------------------------------------*/

4341
int float64_unordered(float64 a, float64 b, float_status *status)
4342
{
P
Peter Maydell 已提交
4343 4344
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
4345 4346 4347 4348

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
P
Peter Maydell 已提交
4349
        float_raise(float_flag_invalid, status);
4350 4351 4352 4353 4354
        return 1;
    }
    return 0;
}

B
bellard 已提交
4355 4356
/*----------------------------------------------------------------------------
| Returns 1 if the double-precision floating-point value `a' is equal to the
4357 4358 4359
| 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
4360 4361
*----------------------------------------------------------------------------*/

4362
int float64_eq_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4363
{
4364
    uint64_t av, bv;
P
Peter Maydell 已提交
4365 4366
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4367 4368 4369 4370

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4371 4372
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4373
            float_raise(float_flag_invalid, status);
4374
        }
B
bellard 已提交
4375 4376
        return 0;
    }
P
pbrook 已提交
4377
    av = float64_val(a);
P
pbrook 已提交
4378
    bv = float64_val(b);
4379
    return ( av == bv ) || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
B
bellard 已提交
4380 4381 4382 4383 4384 4385 4386 4387 4388 4389

}

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

4390
int float64_le_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4391 4392
{
    flag aSign, bSign;
4393
    uint64_t av, bv;
P
Peter Maydell 已提交
4394 4395
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4396 4397 4398 4399

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4400 4401
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4402
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4403 4404 4405 4406 4407
        }
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4408
    av = float64_val(a);
P
pbrook 已提交
4409
    bv = float64_val(b);
4410
    if ( aSign != bSign ) return aSign || ( (uint64_t) ( ( av | bv )<<1 ) == 0 );
P
pbrook 已提交
4411
    return ( av == bv ) || ( aSign ^ ( av < bv ) );
B
bellard 已提交
4412 4413 4414 4415 4416 4417 4418 4419 4420 4421

}

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

4422
int float64_lt_quiet(float64 a, float64 b, float_status *status)
B
bellard 已提交
4423 4424
{
    flag aSign, bSign;
4425
    uint64_t av, bv;
P
Peter Maydell 已提交
4426 4427
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
B
bellard 已提交
4428 4429 4430 4431

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4432 4433
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4434
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4435 4436 4437 4438 4439
        }
        return 0;
    }
    aSign = extractFloat64Sign( a );
    bSign = extractFloat64Sign( b );
P
pbrook 已提交
4440
    av = float64_val(a);
P
pbrook 已提交
4441
    bv = float64_val(b);
4442
    if ( aSign != bSign ) return aSign && ( (uint64_t) ( ( av | bv )<<1 ) != 0 );
P
pbrook 已提交
4443
    return ( av != bv ) && ( aSign ^ ( av < bv ) );
B
bellard 已提交
4444 4445 4446

}

4447 4448 4449 4450 4451 4452 4453
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4454
int float64_unordered_quiet(float64 a, float64 b, float_status *status)
4455
{
P
Peter Maydell 已提交
4456 4457
    a = float64_squash_input_denormal(a, status);
    b = float64_squash_input_denormal(b, status);
4458 4459 4460 4461

    if (    ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
         || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
       ) {
4462 4463
        if (float64_is_signaling_nan(a, status)
         || float64_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
4464
            float_raise(float_flag_invalid, status);
4465 4466 4467 4468 4469 4470
        }
        return 1;
    }
    return 0;
}

B
bellard 已提交
4471 4472 4473 4474 4475 4476 4477 4478 4479 4480
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4481
int32_t floatx80_to_int32(floatx80 a, float_status *status)
B
bellard 已提交
4482 4483
{
    flag aSign;
4484
    int32_t aExp, shiftCount;
4485
    uint64_t aSig;
B
bellard 已提交
4486

4487 4488 4489 4490
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1 << 31;
    }
B
bellard 已提交
4491 4492 4493
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
4494
    if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0;
B
bellard 已提交
4495 4496 4497
    shiftCount = 0x4037 - aExp;
    if ( shiftCount <= 0 ) shiftCount = 1;
    shift64RightJamming( aSig, shiftCount, &aSig );
P
Peter Maydell 已提交
4498
    return roundAndPackInt32(aSign, aSig, status);
B
bellard 已提交
4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511

}

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

4512
int32_t floatx80_to_int32_round_to_zero(floatx80 a, float_status *status)
B
bellard 已提交
4513 4514
{
    flag aSign;
4515
    int32_t aExp, shiftCount;
4516
    uint64_t aSig, savedASig;
4517
    int32_t z;
B
bellard 已提交
4518

4519 4520 4521 4522
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1 << 31;
    }
B
bellard 已提交
4523 4524 4525 4526
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( 0x401E < aExp ) {
4527
        if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) aSign = 0;
B
bellard 已提交
4528 4529 4530
        goto invalid;
    }
    else if ( aExp < 0x3FFF ) {
4531 4532 4533
        if (aExp || aSig) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
4534 4535 4536 4537 4538 4539 4540 4541 4542
        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
4543
        float_raise(float_flag_invalid, status);
4544
        return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
4545 4546
    }
    if ( ( aSig<<shiftCount ) != savedASig ) {
4547
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562
    }
    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.
*----------------------------------------------------------------------------*/

4563
int64_t floatx80_to_int64(floatx80 a, float_status *status)
B
bellard 已提交
4564 4565
{
    flag aSign;
4566
    int32_t aExp, shiftCount;
4567
    uint64_t aSig, aSigExtra;
B
bellard 已提交
4568

4569 4570 4571 4572
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1ULL << 63;
    }
B
bellard 已提交
4573 4574 4575 4576 4577 4578
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    shiftCount = 0x403E - aExp;
    if ( shiftCount <= 0 ) {
        if ( shiftCount ) {
P
Peter Maydell 已提交
4579
            float_raise(float_flag_invalid, status);
4580
            if (!aSign || floatx80_is_any_nan(a)) {
B
bellard 已提交
4581 4582
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
4583
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
4584 4585 4586 4587 4588 4589
        }
        aSigExtra = 0;
    }
    else {
        shift64ExtraRightJamming( aSig, 0, shiftCount, &aSig, &aSigExtra );
    }
P
Peter Maydell 已提交
4590
    return roundAndPackInt64(aSign, aSig, aSigExtra, status);
B
bellard 已提交
4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603

}

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

4604
int64_t floatx80_to_int64_round_to_zero(floatx80 a, float_status *status)
B
bellard 已提交
4605 4606
{
    flag aSign;
4607
    int32_t aExp, shiftCount;
4608
    uint64_t aSig;
4609
    int64_t z;
B
bellard 已提交
4610

4611 4612 4613 4614
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return 1ULL << 63;
    }
B
bellard 已提交
4615 4616 4617 4618 4619 4620 4621
    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
4622
            float_raise(float_flag_invalid, status);
B
bellard 已提交
4623 4624 4625 4626
            if ( ! aSign || ( ( aExp == 0x7FFF ) && aSig ) ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
        }
4627
        return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
4628 4629
    }
    else if ( aExp < 0x3FFF ) {
4630 4631 4632
        if (aExp | aSig) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
4633 4634 4635
        return 0;
    }
    z = aSig>>( - shiftCount );
4636
    if ( (uint64_t) ( aSig<<( shiftCount & 63 ) ) ) {
4637
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650
    }
    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.
*----------------------------------------------------------------------------*/

4651
float32 floatx80_to_float32(floatx80 a, float_status *status)
B
bellard 已提交
4652 4653
{
    flag aSign;
4654
    int32_t aExp;
4655
    uint64_t aSig;
B
bellard 已提交
4656

4657 4658 4659 4660
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float32_default_nan(status);
    }
B
bellard 已提交
4661 4662 4663 4664
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
4665
        if ( (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4666
            return commonNaNToFloat32(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4667 4668 4669 4670 4671
        }
        return packFloat32( aSign, 0xFF, 0 );
    }
    shift64RightJamming( aSig, 33, &aSig );
    if ( aExp || aSig ) aExp -= 0x3F81;
P
Peter Maydell 已提交
4672
    return roundAndPackFloat32(aSign, aExp, aSig, status);
B
bellard 已提交
4673 4674 4675 4676 4677 4678 4679 4680 4681 4682

}

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

4683
float64 floatx80_to_float64(floatx80 a, float_status *status)
B
bellard 已提交
4684 4685
{
    flag aSign;
4686
    int32_t aExp;
4687
    uint64_t aSig, zSig;
B
bellard 已提交
4688

4689 4690 4691 4692
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float64_default_nan(status);
    }
B
bellard 已提交
4693 4694 4695 4696
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
4697
        if ( (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4698
            return commonNaNToFloat64(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4699 4700 4701 4702 4703
        }
        return packFloat64( aSign, 0x7FF, 0 );
    }
    shift64RightJamming( aSig, 1, &zSig );
    if ( aExp || aSig ) aExp -= 0x3C01;
P
Peter Maydell 已提交
4704
    return roundAndPackFloat64(aSign, aExp, zSig, status);
B
bellard 已提交
4705 4706 4707 4708 4709 4710 4711 4712 4713 4714

}

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

4715
float128 floatx80_to_float128(floatx80 a, float_status *status)
B
bellard 已提交
4716 4717
{
    flag aSign;
4718
    int aExp;
4719
    uint64_t aSig, zSig0, zSig1;
B
bellard 已提交
4720

4721 4722 4723 4724
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return float128_default_nan(status);
    }
B
bellard 已提交
4725 4726 4727
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
4728
    if ( ( aExp == 0x7FFF ) && (uint64_t) ( aSig<<1 ) ) {
P
Peter Maydell 已提交
4729
        return commonNaNToFloat128(floatx80ToCommonNaN(a, status), status);
B
bellard 已提交
4730 4731 4732 4733 4734 4735
    }
    shift128Right( aSig<<1, 0, 16, &zSig0, &zSig1 );
    return packFloat128( aSign, aExp, zSig0, zSig1 );

}

4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751
/*----------------------------------------------------------------------------
| 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
4752 4753 4754 4755 4756 4757 4758
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

4759
floatx80 floatx80_round_to_int(floatx80 a, float_status *status)
B
bellard 已提交
4760 4761
{
    flag aSign;
4762
    int32_t aExp;
4763
    uint64_t lastBitMask, roundBitsMask;
B
bellard 已提交
4764 4765
    floatx80 z;

4766 4767 4768 4769
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
4770 4771
    aExp = extractFloatx80Exp( a );
    if ( 0x403E <= aExp ) {
4772
        if ( ( aExp == 0x7FFF ) && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) {
P
Peter Maydell 已提交
4773
            return propagateFloatx80NaN(a, a, status);
B
bellard 已提交
4774 4775 4776 4777 4778
        }
        return a;
    }
    if ( aExp < 0x3FFF ) {
        if (    ( aExp == 0 )
4779
             && ( (uint64_t) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) {
B
bellard 已提交
4780 4781
            return a;
        }
4782
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
4783
        aSign = extractFloatx80Sign( a );
4784
        switch (status->float_rounding_mode) {
B
bellard 已提交
4785
         case float_round_nearest_even:
4786
            if ( ( aExp == 0x3FFE ) && (uint64_t) ( extractFloatx80Frac( a )<<1 )
B
bellard 已提交
4787 4788 4789 4790 4791
               ) {
                return
                    packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) );
            }
            break;
4792 4793 4794 4795 4796
        case float_round_ties_away:
            if (aExp == 0x3FFE) {
                return packFloatx80(aSign, 0x3FFF, LIT64(0x8000000000000000));
            }
            break;
B
bellard 已提交
4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812
         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;
4813
    switch (status->float_rounding_mode) {
4814
    case float_round_nearest_even:
B
bellard 已提交
4815
        z.low += lastBitMask>>1;
4816 4817 4818 4819
        if ((z.low & roundBitsMask) == 0) {
            z.low &= ~lastBitMask;
        }
        break;
4820 4821 4822
    case float_round_ties_away:
        z.low += lastBitMask >> 1;
        break;
4823 4824 4825 4826 4827 4828 4829 4830 4831
    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
4832 4833
            z.low += roundBitsMask;
        }
4834 4835 4836
        break;
    default:
        abort();
B
bellard 已提交
4837 4838 4839 4840 4841 4842
    }
    z.low &= ~ roundBitsMask;
    if ( z.low == 0 ) {
        ++z.high;
        z.low = LIT64( 0x8000000000000000 );
    }
4843 4844 4845
    if (z.low != a.low) {
        status->float_exception_flags |= float_flag_inexact;
    }
B
bellard 已提交
4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857
    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.
*----------------------------------------------------------------------------*/

4858 4859
static floatx80 addFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
                                float_status *status)
B
bellard 已提交
4860
{
4861
    int32_t aExp, bExp, zExp;
4862
    uint64_t aSig, bSig, zSig0, zSig1;
4863
    int32_t expDiff;
B
bellard 已提交
4864 4865 4866 4867 4868 4869 4870 4871

    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
4872 4873 4874
            if ((uint64_t)(aSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
B
bellard 已提交
4875 4876 4877 4878 4879 4880 4881 4882
            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
4883 4884 4885
            if ((uint64_t)(bSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
4886 4887 4888
            return packFloatx80(zSign,
                                floatx80_infinity_high,
                                floatx80_infinity_low);
B
bellard 已提交
4889 4890 4891 4892 4893 4894 4895
        }
        if ( aExp == 0 ) ++expDiff;
        shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
        zExp = bExp;
    }
    else {
        if ( aExp == 0x7FFF ) {
4896
            if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) {
P
Peter Maydell 已提交
4897
                return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910
            }
            return a;
        }
        zSig1 = 0;
        zSig0 = aSig + bSig;
        if ( aExp == 0 ) {
            normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 );
            goto roundAndPack;
        }
        zExp = aExp;
        goto shiftRight1;
    }
    zSig0 = aSig + bSig;
4911
    if ( (int64_t) zSig0 < 0 ) goto roundAndPack;
B
bellard 已提交
4912 4913 4914 4915 4916
 shiftRight1:
    shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 );
    zSig0 |= LIT64( 0x8000000000000000 );
    ++zExp;
 roundAndPack:
4917
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
4918
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
4919 4920 4921 4922 4923 4924 4925 4926 4927 4928
}

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

4929 4930
static floatx80 subFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
                                float_status *status)
B
bellard 已提交
4931
{
4932
    int32_t aExp, bExp, zExp;
4933
    uint64_t aSig, bSig, zSig0, zSig1;
4934
    int32_t expDiff;
B
bellard 已提交
4935 4936 4937 4938 4939 4940 4941 4942 4943

    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 ) {
4944
        if ( (uint64_t) ( ( aSig | bSig )<<1 ) ) {
P
Peter Maydell 已提交
4945
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
4946
        }
P
Peter Maydell 已提交
4947
        float_raise(float_flag_invalid, status);
4948
        return floatx80_default_nan(status);
B
bellard 已提交
4949 4950 4951 4952 4953 4954 4955 4956
    }
    if ( aExp == 0 ) {
        aExp = 1;
        bExp = 1;
    }
    zSig1 = 0;
    if ( bSig < aSig ) goto aBigger;
    if ( aSig < bSig ) goto bBigger;
4957
    return packFloatx80(status->float_rounding_mode == float_round_down, 0, 0);
B
bellard 已提交
4958 4959
 bExpBigger:
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
4960 4961 4962
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
4963 4964
        return packFloatx80(zSign ^ 1, floatx80_infinity_high,
                            floatx80_infinity_low);
B
bellard 已提交
4965 4966 4967 4968 4969 4970 4971 4972 4973 4974
    }
    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
4975 4976 4977
        if ((uint64_t)(aSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
4978 4979 4980 4981 4982 4983 4984 4985
        return a;
    }
    if ( bExp == 0 ) --expDiff;
    shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
 aBigger:
    sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 );
    zExp = aExp;
 normalizeRoundAndPack:
4986
    return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
4987
                                         zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
4988 4989 4990 4991 4992 4993 4994 4995
}

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

4996
floatx80 floatx80_add(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
4997 4998 4999
{
    flag aSign, bSign;

5000 5001 5002 5003
    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
5004 5005 5006
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
5007
        return addFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5008 5009
    }
    else {
P
Peter Maydell 已提交
5010
        return subFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5011 5012 5013 5014 5015 5016 5017 5018 5019 5020
    }

}

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

5021
floatx80 floatx80_sub(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5022 5023 5024
{
    flag aSign, bSign;

5025 5026 5027 5028
    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
5029 5030 5031
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
5032
        return subFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5033 5034
    }
    else {
P
Peter Maydell 已提交
5035
        return addFloatx80Sigs(a, b, aSign, status);
B
bellard 已提交
5036 5037 5038 5039 5040 5041 5042 5043 5044 5045
    }

}

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

5046
floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5047 5048
{
    flag aSign, bSign, zSign;
5049
    int32_t aExp, bExp, zExp;
5050
    uint64_t aSig, bSig, zSig0, zSig1;
B
bellard 已提交
5051

5052 5053 5054 5055
    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
5056 5057 5058 5059 5060 5061 5062 5063
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    bSign = extractFloatx80Sign( b );
    zSign = aSign ^ bSign;
    if ( aExp == 0x7FFF ) {
5064 5065
        if (    (uint64_t) ( aSig<<1 )
             || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) {
P
Peter Maydell 已提交
5066
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
5067 5068
        }
        if ( ( bExp | bSig ) == 0 ) goto invalid;
5069 5070
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5071 5072
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5073 5074 5075
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5076 5077
        if ( ( aExp | aSig ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
5078
            float_raise(float_flag_invalid, status);
5079
            return floatx80_default_nan(status);
B
bellard 已提交
5080
        }
5081 5082
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093
    }
    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 );
5094
    if ( 0 < (int64_t) zSig0 ) {
B
bellard 已提交
5095 5096 5097
        shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 );
        --zExp;
    }
5098
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
5099
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
5100 5101 5102 5103 5104 5105 5106 5107
}

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

5108
floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5109 5110
{
    flag aSign, bSign, zSign;
5111
    int32_t aExp, bExp, zExp;
5112 5113
    uint64_t aSig, bSig, zSig0, zSig1;
    uint64_t rem0, rem1, rem2, term0, term1, term2;
B
bellard 已提交
5114

5115 5116 5117 5118
    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
5119 5120 5121 5122 5123 5124 5125 5126
    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
5127 5128 5129
        if ((uint64_t)(aSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5130
        if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5131 5132 5133
            if ((uint64_t)(bSig << 1)) {
                return propagateFloatx80NaN(a, b, status);
            }
B
bellard 已提交
5134 5135
            goto invalid;
        }
5136 5137
        return packFloatx80(zSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5138 5139
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5140 5141 5142
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5143 5144 5145 5146 5147 5148
        return packFloatx80( zSign, 0, 0 );
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
            if ( ( aExp | aSig ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
5149
                float_raise(float_flag_invalid, status);
5150
                return floatx80_default_nan(status);
B
bellard 已提交
5151
            }
P
Peter Maydell 已提交
5152
            float_raise(float_flag_divbyzero, status);
5153 5154
            return packFloatx80(zSign, floatx80_infinity_high,
                                       floatx80_infinity_low);
B
bellard 已提交
5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170
        }
        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 );
5171
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
5172 5173 5174 5175
        --zSig0;
        add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
    }
    zSig1 = estimateDiv128To64( rem1, 0, bSig );
5176
    if ( (uint64_t) ( zSig1<<1 ) <= 8 ) {
B
bellard 已提交
5177 5178
        mul64To128( bSig, zSig1, &term1, &term2 );
        sub128( rem1, 0, term1, term2, &rem1, &rem2 );
5179
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
5180 5181 5182 5183 5184
            --zSig1;
            add128( rem1, rem2, 0, bSig, &rem1, &rem2 );
        }
        zSig1 |= ( ( rem1 | rem2 ) != 0 );
    }
5185
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
P
Peter Maydell 已提交
5186
                                zSign, zExp, zSig0, zSig1, status);
B
bellard 已提交
5187 5188 5189 5190 5191 5192 5193 5194
}

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

5195
floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5196
{
5197
    flag aSign, zSign;
5198
    int32_t aExp, bExp, expDiff;
5199 5200
    uint64_t aSig0, aSig1, bSig;
    uint64_t q, term0, term1, alternateASig0, alternateASig1;
B
bellard 已提交
5201

5202 5203 5204 5205
    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
5206 5207 5208 5209 5210 5211
    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    bSig = extractFloatx80Frac( b );
    bExp = extractFloatx80Exp( b );
    if ( aExp == 0x7FFF ) {
5212 5213
        if (    (uint64_t) ( aSig0<<1 )
             || ( ( bExp == 0x7FFF ) && (uint64_t) ( bSig<<1 ) ) ) {
P
Peter Maydell 已提交
5214
            return propagateFloatx80NaN(a, b, status);
B
bellard 已提交
5215 5216 5217 5218
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
5219 5220 5221
        if ((uint64_t)(bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
B
bellard 已提交
5222 5223 5224 5225 5226
        return a;
    }
    if ( bExp == 0 ) {
        if ( bSig == 0 ) {
 invalid:
P
Peter Maydell 已提交
5227
            float_raise(float_flag_invalid, status);
5228
            return floatx80_default_nan(status);
B
bellard 已提交
5229 5230 5231 5232
        }
        normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
    }
    if ( aExp == 0 ) {
5233
        if ( (uint64_t) ( aSig0<<1 ) == 0 ) return a;
B
bellard 已提交
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 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283
        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
5284
            80, zSign, bExp + expDiff, aSig0, aSig1, status);
B
bellard 已提交
5285 5286 5287 5288 5289 5290 5291 5292 5293

}

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

5294
floatx80 floatx80_sqrt(floatx80 a, float_status *status)
B
bellard 已提交
5295 5296
{
    flag aSign;
5297
    int32_t aExp, zExp;
5298 5299
    uint64_t aSig0, aSig1, zSig0, zSig1, doubleZSig0;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
5300

5301 5302 5303 5304
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
B
bellard 已提交
5305 5306 5307 5308
    aSig0 = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );
    if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
5309 5310 5311
        if ((uint64_t)(aSig0 << 1)) {
            return propagateFloatx80NaN(a, a, status);
        }
B
bellard 已提交
5312 5313 5314 5315 5316 5317
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 ) == 0 ) return a;
 invalid:
P
Peter Maydell 已提交
5318
        float_raise(float_flag_invalid, status);
5319
        return floatx80_default_nan(status);
B
bellard 已提交
5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331
    }
    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 );
5332
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343
        --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 );
5344
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
5345 5346 5347 5348 5349 5350 5351 5352 5353 5354
            --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;
5355 5356
    return roundAndPackFloatx80(status->floatx80_rounding_precision,
                                0, zExp, zSig0, zSig1, status);
B
bellard 已提交
5357 5358 5359
}

/*----------------------------------------------------------------------------
5360 5361 5362 5363
| 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
5364 5365
*----------------------------------------------------------------------------*/

5366
int floatx80_eq(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5367 5368
{

5369 5370 5371 5372 5373
    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
5374
       ) {
P
Peter Maydell 已提交
5375
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5376 5377 5378 5379 5380 5381
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
5382
                  && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
5383 5384 5385 5386 5387 5388 5389
           );

}

/*----------------------------------------------------------------------------
| 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
5390 5391 5392
| 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
5393 5394
*----------------------------------------------------------------------------*/

5395
int floatx80_le(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5396 5397 5398
{
    flag aSign, bSign;

5399 5400 5401 5402 5403
    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
5404
       ) {
P
Peter Maydell 已提交
5405
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5406 5407 5408 5409 5410 5411 5412
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5413
            || (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5414 5415 5416 5417 5418 5419 5420 5421 5422 5423
                 == 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
5424 5425 5426
| 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
5427 5428
*----------------------------------------------------------------------------*/

5429
int floatx80_lt(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5430 5431 5432
{
    flag aSign, bSign;

5433 5434 5435 5436 5437
    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
5438
       ) {
P
Peter Maydell 已提交
5439
        float_raise(float_flag_invalid, status);
B
bellard 已提交
5440 5441 5442 5443 5444 5445 5446
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5447
            && (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5448 5449 5450 5451 5452 5453 5454 5455
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

5456 5457
/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point values `a' and `b'
5458 5459 5460
| 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.
5461
*----------------------------------------------------------------------------*/
5462
int floatx80_unordered(floatx80 a, floatx80 b, float_status *status)
5463
{
5464 5465 5466 5467 5468
    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))
5469
       ) {
P
Peter Maydell 已提交
5470
        float_raise(float_flag_invalid, status);
5471 5472 5473 5474 5475
        return 1;
    }
    return 0;
}

B
bellard 已提交
5476
/*----------------------------------------------------------------------------
5477
| Returns 1 if the extended double-precision floating-point value `a' is
5478 5479 5480
| 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
5481 5482
*----------------------------------------------------------------------------*/

5483
int floatx80_eq_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5484 5485
{

5486 5487 5488 5489
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5490
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5491
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5492
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5493
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5494
       ) {
5495 5496
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5497
            float_raise(float_flag_invalid, status);
5498
        }
B
bellard 已提交
5499 5500 5501 5502 5503 5504
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
5505
                  && ( (uint16_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516
           );

}

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

5517
int floatx80_le_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5518 5519 5520
{
    flag aSign, bSign;

5521 5522 5523 5524
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5525
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5526
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5527
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5528
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5529
       ) {
5530 5531
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5532
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5533 5534 5535 5536 5537 5538 5539 5540
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5541
            || (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556
                 == 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.
*----------------------------------------------------------------------------*/

5557
int floatx80_lt_quiet(floatx80 a, floatx80 b, float_status *status)
B
bellard 已提交
5558 5559 5560
{
    flag aSign, bSign;

5561 5562 5563 5564
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 0;
    }
B
bellard 已提交
5565
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
5566
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
B
bellard 已提交
5567
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
5568
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
B
bellard 已提交
5569
       ) {
5570 5571
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5572
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5573 5574 5575 5576 5577 5578 5579 5580
        }
        return 0;
    }
    aSign = extractFloatx80Sign( a );
    bSign = extractFloatx80Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
5581
            && (    ( ( (uint16_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
5582 5583 5584 5585 5586 5587 5588 5589
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

5590 5591 5592 5593 5594 5595
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/
5596
int floatx80_unordered_quiet(floatx80 a, floatx80 b, float_status *status)
5597
{
5598 5599 5600 5601
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return 1;
    }
5602 5603 5604 5605 5606
    if (    (    ( extractFloatx80Exp( a ) == 0x7FFF )
              && (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
         || (    ( extractFloatx80Exp( b ) == 0x7FFF )
              && (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
       ) {
5607 5608
        if (floatx80_is_signaling_nan(a, status)
         || floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
5609
            float_raise(float_flag_invalid, status);
5610 5611 5612 5613 5614 5615
        }
        return 1;
    }
    return 0;
}

B
bellard 已提交
5616 5617 5618 5619 5620 5621 5622 5623 5624 5625
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

5626
int32_t float128_to_int32(float128 a, float_status *status)
B
bellard 已提交
5627 5628
{
    flag aSign;
5629
    int32_t aExp, shiftCount;
5630
    uint64_t aSig0, aSig1;
B
bellard 已提交
5631 5632 5633 5634 5635 5636 5637 5638 5639 5640

    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
5641
    return roundAndPackInt32(aSign, aSig0, status);
B
bellard 已提交
5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654

}

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

5655
int32_t float128_to_int32_round_to_zero(float128 a, float_status *status)
B
bellard 已提交
5656 5657
{
    flag aSign;
5658
    int32_t aExp, shiftCount;
5659
    uint64_t aSig0, aSig1, savedASig;
5660
    int32_t z;
B
bellard 已提交
5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671

    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 ) {
5672 5673 5674
        if (aExp || aSig0) {
            status->float_exception_flags |= float_flag_inexact;
        }
B
bellard 已提交
5675 5676 5677 5678 5679 5680 5681 5682 5683 5684
        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
5685
        float_raise(float_flag_invalid, status);
5686
        return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
B
bellard 已提交
5687 5688
    }
    if ( ( aSig0<<shiftCount ) != savedASig ) {
5689
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703 5704
    }
    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.
*----------------------------------------------------------------------------*/

5705
int64_t float128_to_int64(float128 a, float_status *status)
B
bellard 已提交
5706 5707
{
    flag aSign;
5708
    int32_t aExp, shiftCount;
5709
    uint64_t aSig0, aSig1;
B
bellard 已提交
5710 5711 5712 5713 5714 5715 5716 5717 5718

    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
5719
            float_raise(float_flag_invalid, status);
B
bellard 已提交
5720 5721 5722 5723 5724 5725 5726
            if (    ! aSign
                 || (    ( aExp == 0x7FFF )
                      && ( aSig1 || ( aSig0 != LIT64( 0x0001000000000000 ) ) )
                    )
               ) {
                return LIT64( 0x7FFFFFFFFFFFFFFF );
            }
5727
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
5728 5729 5730 5731 5732 5733
        }
        shortShift128Left( aSig0, aSig1, - shiftCount, &aSig0, &aSig1 );
    }
    else {
        shift64ExtraRightJamming( aSig0, aSig1, shiftCount, &aSig0, &aSig1 );
    }
P
Peter Maydell 已提交
5734
    return roundAndPackInt64(aSign, aSig0, aSig1, status);
B
bellard 已提交
5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747

}

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

5748
int64_t float128_to_int64_round_to_zero(float128 a, float_status *status)
B
bellard 已提交
5749 5750
{
    flag aSign;
5751
    int32_t aExp, shiftCount;
5752
    uint64_t aSig0, aSig1;
5753
    int64_t z;
B
bellard 已提交
5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765

    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 ) ) ) {
5766 5767 5768
                if (aSig1) {
                    status->float_exception_flags |= float_flag_inexact;
                }
B
bellard 已提交
5769 5770
            }
            else {
P
Peter Maydell 已提交
5771
                float_raise(float_flag_invalid, status);
B
bellard 已提交
5772 5773 5774 5775
                if ( ! aSign || ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) ) {
                    return LIT64( 0x7FFFFFFFFFFFFFFF );
                }
            }
5776
            return (int64_t) LIT64( 0x8000000000000000 );
B
bellard 已提交
5777 5778
        }
        z = ( aSig0<<shiftCount ) | ( aSig1>>( ( - shiftCount ) & 63 ) );
5779
        if ( (uint64_t) ( aSig1<<shiftCount ) ) {
5780
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5781 5782 5783 5784 5785
        }
    }
    else {
        if ( aExp < 0x3FFF ) {
            if ( aExp | aSig0 | aSig1 ) {
5786
                status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5787 5788 5789 5790 5791
            }
            return 0;
        }
        z = aSig0>>( - shiftCount );
        if (    aSig1
5792
             || ( shiftCount && (uint64_t) ( aSig0<<( shiftCount & 63 ) ) ) ) {
5793
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
5794 5795 5796 5797 5798 5799 5800
        }
    }
    if ( aSign ) z = - z;
    return z;

}

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 5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859
/*----------------------------------------------------------------------------
| 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
5860 5861
/*----------------------------------------------------------------------------
| Returns the result of converting the quadruple-precision floating-point
5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889
| 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
5890 5891 5892 5893 5894
| value `a' to the single-precision floating-point format.  The conversion
| is performed according to the IEC/IEEE Standard for Binary Floating-Point
| Arithmetic.
*----------------------------------------------------------------------------*/

5895
float32 float128_to_float32(float128 a, float_status *status)
B
bellard 已提交
5896 5897
{
    flag aSign;
5898
    int32_t aExp;
5899 5900
    uint64_t aSig0, aSig1;
    uint32_t zSig;
B
bellard 已提交
5901 5902 5903 5904 5905 5906 5907

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5908
            return commonNaNToFloat32(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5909 5910 5911 5912 5913 5914 5915 5916 5917 5918
        }
        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
5919
    return roundAndPackFloat32(aSign, aExp, zSig, status);
B
bellard 已提交
5920 5921 5922 5923 5924 5925 5926 5927 5928 5929

}

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

5930
float64 float128_to_float64(float128 a, float_status *status)
B
bellard 已提交
5931 5932
{
    flag aSign;
5933
    int32_t aExp;
5934
    uint64_t aSig0, aSig1;
B
bellard 已提交
5935 5936 5937 5938 5939 5940 5941

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5942
            return commonNaNToFloat64(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5943 5944 5945 5946 5947 5948 5949 5950 5951
        }
        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
5952
    return roundAndPackFloat64(aSign, aExp, aSig0, status);
B
bellard 已提交
5953 5954 5955 5956 5957 5958 5959 5960 5961 5962

}

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

5963
floatx80 float128_to_floatx80(float128 a, float_status *status)
B
bellard 已提交
5964 5965
{
    flag aSign;
5966
    int32_t aExp;
5967
    uint64_t aSig0, aSig1;
B
bellard 已提交
5968 5969 5970 5971 5972 5973 5974

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
5975
            return commonNaNToFloatx80(float128ToCommonNaN(a, status), status);
B
bellard 已提交
5976
        }
5977 5978
        return packFloatx80(aSign, floatx80_infinity_high,
                                   floatx80_infinity_low);
B
bellard 已提交
5979 5980 5981 5982 5983 5984 5985 5986 5987
    }
    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
5988
    return roundAndPackFloatx80(80, aSign, aExp, aSig0, aSig1, status);
B
bellard 已提交
5989 5990 5991 5992 5993 5994 5995 5996 5997 5998

}

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

5999
float128 float128_round_to_int(float128 a, float_status *status)
B
bellard 已提交
6000 6001
{
    flag aSign;
6002
    int32_t aExp;
6003
    uint64_t lastBitMask, roundBitsMask;
B
bellard 已提交
6004 6005 6006 6007 6008 6009 6010 6011
    float128 z;

    aExp = extractFloat128Exp( a );
    if ( 0x402F <= aExp ) {
        if ( 0x406F <= aExp ) {
            if (    ( aExp == 0x7FFF )
                 && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) )
               ) {
P
Peter Maydell 已提交
6012
                return propagateFloat128NaN(a, a, status);
B
bellard 已提交
6013 6014 6015 6016 6017 6018 6019
            }
            return a;
        }
        lastBitMask = 1;
        lastBitMask = ( lastBitMask<<( 0x406E - aExp ) )<<1;
        roundBitsMask = lastBitMask - 1;
        z = a;
6020
        switch (status->float_rounding_mode) {
6021
        case float_round_nearest_even:
B
bellard 已提交
6022 6023 6024 6025 6026
            if ( lastBitMask ) {
                add128( z.high, z.low, 0, lastBitMask>>1, &z.high, &z.low );
                if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask;
            }
            else {
6027
                if ( (int64_t) z.low < 0 ) {
B
bellard 已提交
6028
                    ++z.high;
6029
                    if ( (uint64_t) ( z.low<<1 ) == 0 ) z.high &= ~1;
B
bellard 已提交
6030 6031
                }
            }
6032
            break;
6033 6034 6035 6036 6037 6038 6039 6040 6041
        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;
6042 6043 6044 6045 6046 6047 6048 6049 6050 6051
        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
6052
            }
6053 6054 6055
            break;
        default:
            abort();
B
bellard 已提交
6056 6057 6058 6059 6060
        }
        z.low &= ~ roundBitsMask;
    }
    else {
        if ( aExp < 0x3FFF ) {
6061
            if ( ( ( (uint64_t) ( a.high<<1 ) ) | a.low ) == 0 ) return a;
6062
            status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
6063
            aSign = extractFloat128Sign( a );
6064
            switch (status->float_rounding_mode) {
B
bellard 已提交
6065 6066 6067 6068 6069 6070 6071 6072
             case float_round_nearest_even:
                if (    ( aExp == 0x3FFE )
                     && (   extractFloat128Frac0( a )
                          | extractFloat128Frac1( a ) )
                   ) {
                    return packFloat128( aSign, 0x3FFF, 0, 0 );
                }
                break;
6073 6074 6075 6076 6077
            case float_round_ties_away:
                if (aExp == 0x3FFE) {
                    return packFloat128(aSign, 0x3FFF, 0, 0);
                }
                break;
B
bellard 已提交
6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093
             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;
6094
        switch (status->float_rounding_mode) {
6095
        case float_round_nearest_even:
B
bellard 已提交
6096 6097 6098 6099
            z.high += lastBitMask>>1;
            if ( ( ( z.high & roundBitsMask ) | a.low ) == 0 ) {
                z.high &= ~ lastBitMask;
            }
6100
            break;
6101 6102 6103
        case float_round_ties_away:
            z.high += lastBitMask>>1;
            break;
6104 6105 6106 6107
        case float_round_to_zero:
            break;
        case float_round_up:
            if (!extractFloat128Sign(z)) {
B
bellard 已提交
6108 6109 6110
                z.high |= ( a.low != 0 );
                z.high += roundBitsMask;
            }
6111 6112 6113 6114 6115 6116 6117 6118 6119
            break;
        case float_round_down:
            if (extractFloat128Sign(z)) {
                z.high |= (a.low != 0);
                z.high += roundBitsMask;
            }
            break;
        default:
            abort();
B
bellard 已提交
6120 6121 6122 6123
        }
        z.high &= ~ roundBitsMask;
    }
    if ( ( z.low != a.low ) || ( z.high != a.high ) ) {
6124
        status->float_exception_flags |= float_flag_inexact;
B
bellard 已提交
6125 6126 6127 6128 6129 6130 6131 6132 6133 6134 6135 6136 6137
    }
    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.
*----------------------------------------------------------------------------*/

6138 6139
static float128 addFloat128Sigs(float128 a, float128 b, flag zSign,
                                float_status *status)
B
bellard 已提交
6140
{
6141
    int32_t aExp, bExp, zExp;
6142
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
6143
    int32_t expDiff;
B
bellard 已提交
6144 6145 6146 6147 6148 6149 6150 6151 6152 6153

    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
6154 6155 6156
            if (aSig0 | aSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167 6168 6169 6170
            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
6171 6172 6173
            if (bSig0 | bSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6174 6175 6176 6177 6178 6179 6180 6181 6182 6183 6184 6185 6186 6187 6188
            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
6189
                return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6190 6191 6192 6193
            }
            return a;
        }
        add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
6194
        if ( aExp == 0 ) {
6195
            if (status->flush_to_zero) {
6196
                if (zSig0 | zSig1) {
P
Peter Maydell 已提交
6197
                    float_raise(float_flag_output_denormal, status);
6198 6199 6200
                }
                return packFloat128(zSign, 0, 0, 0);
            }
6201 6202
            return packFloat128( zSign, 0, zSig0, zSig1 );
        }
B
bellard 已提交
6203 6204 6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216
        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
6217
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228

}

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

6229 6230
static float128 subFloat128Sigs(float128 a, float128 b, flag zSign,
                                float_status *status)
B
bellard 已提交
6231
{
6232
    int32_t aExp, bExp, zExp;
6233
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1;
6234
    int32_t expDiff;
B
bellard 已提交
6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248

    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
6249
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6250
        }
P
Peter Maydell 已提交
6251
        float_raise(float_flag_invalid, status);
6252
        return float128_default_nan(status);
B
bellard 已提交
6253 6254 6255 6256 6257 6258 6259 6260 6261
    }
    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;
6262 6263
    return packFloat128(status->float_rounding_mode == float_round_down,
                        0, 0, 0);
B
bellard 已提交
6264 6265
 bExpBigger:
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6266 6267 6268
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285
        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
6286 6287 6288
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303
        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
6304 6305
    return normalizeRoundAndPackFloat128(zSign, zExp - 14, zSig0, zSig1,
                                         status);
B
bellard 已提交
6306 6307 6308 6309 6310 6311 6312 6313 6314

}

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

6315
float128 float128_add(float128 a, float128 b, float_status *status)
B
bellard 已提交
6316 6317 6318 6319 6320 6321
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
6322
        return addFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6323 6324
    }
    else {
P
Peter Maydell 已提交
6325
        return subFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6326 6327 6328 6329 6330 6331 6332 6333 6334 6335
    }

}

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

6336
float128 float128_sub(float128 a, float128 b, float_status *status)
B
bellard 已提交
6337 6338 6339 6340 6341 6342
{
    flag aSign, bSign;

    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign == bSign ) {
P
Peter Maydell 已提交
6343
        return subFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6344 6345
    }
    else {
P
Peter Maydell 已提交
6346
        return addFloat128Sigs(a, b, aSign, status);
B
bellard 已提交
6347 6348 6349 6350 6351 6352 6353 6354 6355 6356
    }

}

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

6357
float128 float128_mul(float128 a, float128 b, float_status *status)
B
bellard 已提交
6358 6359
{
    flag aSign, bSign, zSign;
6360
    int32_t aExp, bExp, zExp;
6361
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2, zSig3;
B
bellard 已提交
6362 6363 6364 6365 6366 6367 6368 6369 6370 6371 6372 6373 6374

    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
6375
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6376 6377 6378 6379 6380
        }
        if ( ( bExp | bSig0 | bSig1 ) == 0 ) goto invalid;
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6381 6382 6383
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6384 6385
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
6386
            float_raise(float_flag_invalid, status);
6387
            return float128_default_nan(status);
B
bellard 已提交
6388 6389 6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409
        }
        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
6410
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6411 6412 6413 6414 6415 6416 6417 6418 6419

}

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

6420
float128 float128_div(float128 a, float128 b, float_status *status)
B
bellard 已提交
6421 6422
{
    flag aSign, bSign, zSign;
6423
    int32_t aExp, bExp, zExp;
6424 6425
    uint64_t aSig0, aSig1, bSig0, bSig1, zSig0, zSig1, zSig2;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
6426 6427 6428 6429 6430 6431 6432 6433 6434 6435 6436

    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
6437 6438 6439
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6440
        if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6441 6442 6443
            if (bSig0 | bSig1) {
                return propagateFloat128NaN(a, b, status);
            }
B
bellard 已提交
6444 6445 6446 6447 6448
            goto invalid;
        }
        return packFloat128( zSign, 0x7FFF, 0, 0 );
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6449 6450 6451
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6452 6453 6454 6455 6456 6457
        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
6458
                float_raise(float_flag_invalid, status);
6459
                return float128_default_nan(status);
B
bellard 已提交
6460
            }
P
Peter Maydell 已提交
6461
            float_raise(float_flag_divbyzero, status);
B
bellard 已提交
6462 6463 6464 6465 6466 6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481
            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 );
6482
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
6483 6484 6485 6486 6487 6488 6489
        --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 );
6490
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
6491 6492 6493 6494 6495 6496
            --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
6497
    return roundAndPackFloat128(zSign, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6498 6499 6500 6501 6502 6503 6504 6505 6506

}

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

6507
float128 float128_rem(float128 a, float128 b, float_status *status)
B
bellard 已提交
6508
{
6509
    flag aSign, zSign;
6510
    int32_t aExp, bExp, expDiff;
6511 6512 6513
    uint64_t aSig0, aSig1, bSig0, bSig1, q, term0, term1, term2;
    uint64_t allZero, alternateASig0, alternateASig1, sigMean1;
    int64_t sigMean0;
B
bellard 已提交
6514 6515 6516 6517 6518 6519 6520 6521 6522 6523 6524

    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
6525
            return propagateFloat128NaN(a, b, status);
B
bellard 已提交
6526 6527 6528 6529
        }
        goto invalid;
    }
    if ( bExp == 0x7FFF ) {
P
Peter Maydell 已提交
6530 6531 6532
        if (bSig0 | bSig1) {
            return propagateFloat128NaN(a, b, status);
        }
B
bellard 已提交
6533 6534 6535 6536 6537
        return a;
    }
    if ( bExp == 0 ) {
        if ( ( bSig0 | bSig1 ) == 0 ) {
 invalid:
P
Peter Maydell 已提交
6538
            float_raise(float_flag_invalid, status);
6539
            return float128_default_nan(status);
B
bellard 已提交
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 6575 6576 6577 6578 6579 6580 6581 6582 6583 6584 6585 6586 6587 6588 6589 6590 6591 6592 6593
        }
        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 );
6594
    } while ( 0 <= (int64_t) aSig0 );
B
bellard 已提交
6595
    add128(
6596
        aSig0, aSig1, alternateASig0, alternateASig1, (uint64_t *)&sigMean0, &sigMean1 );
B
bellard 已提交
6597 6598 6599 6600 6601
    if (    ( sigMean0 < 0 )
         || ( ( ( sigMean0 | sigMean1 ) == 0 ) && ( q & 1 ) ) ) {
        aSig0 = alternateASig0;
        aSig1 = alternateASig1;
    }
6602
    zSign = ( (int64_t) aSig0 < 0 );
B
bellard 已提交
6603
    if ( zSign ) sub128( 0, 0, aSig0, aSig1, &aSig0, &aSig1 );
P
Peter Maydell 已提交
6604 6605
    return normalizeRoundAndPackFloat128(aSign ^ zSign, bExp - 4, aSig0, aSig1,
                                         status);
B
bellard 已提交
6606 6607 6608 6609 6610 6611 6612 6613
}

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

6614
float128 float128_sqrt(float128 a, float_status *status)
B
bellard 已提交
6615 6616
{
    flag aSign;
6617
    int32_t aExp, zExp;
6618 6619
    uint64_t aSig0, aSig1, zSig0, zSig1, zSig2, doubleZSig0;
    uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
B
bellard 已提交
6620 6621 6622 6623 6624 6625

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
P
Peter Maydell 已提交
6626 6627 6628
        if (aSig0 | aSig1) {
            return propagateFloat128NaN(a, a, status);
        }
B
bellard 已提交
6629 6630 6631 6632 6633 6634
        if ( ! aSign ) return a;
        goto invalid;
    }
    if ( aSign ) {
        if ( ( aExp | aSig0 | aSig1 ) == 0 ) return a;
 invalid:
P
Peter Maydell 已提交
6635
        float_raise(float_flag_invalid, status);
6636
        return float128_default_nan(status);
B
bellard 已提交
6637 6638 6639 6640 6641 6642 6643 6644 6645 6646 6647 6648 6649
    }
    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 );
6650
    while ( (int64_t) rem0 < 0 ) {
B
bellard 已提交
6651 6652 6653 6654 6655 6656 6657 6658 6659 6660 6661
        --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 );
6662
        while ( (int64_t) rem1 < 0 ) {
B
bellard 已提交
6663 6664 6665 6666 6667 6668 6669 6670 6671
            --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
6672
    return roundAndPackFloat128(0, zExp, zSig0, zSig1, zSig2, status);
B
bellard 已提交
6673 6674 6675 6676 6677

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
6678 6679
| 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
6680 6681 6682
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/

6683
int float128_eq(float128 a, float128 b, float_status *status)
B
bellard 已提交
6684 6685 6686 6687 6688 6689 6690
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6691
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6692 6693 6694 6695 6696 6697
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
6698
                  && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
6699 6700 6701 6702 6703 6704
           );

}

/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is less than
6705 6706 6707
| 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
6708 6709
*----------------------------------------------------------------------------*/

6710
int float128_le(float128 a, float128 b, float_status *status)
B
bellard 已提交
6711 6712 6713 6714 6715 6716 6717 6718
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6719
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6720 6721 6722 6723 6724 6725 6726
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6727
            || (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6728 6729 6730 6731 6732 6733 6734 6735 6736 6737
                 == 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
6738 6739 6740
| 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
6741 6742
*----------------------------------------------------------------------------*/

6743
int float128_lt(float128 a, float128 b, float_status *status)
B
bellard 已提交
6744 6745 6746 6747 6748 6749 6750 6751
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6752
        float_raise(float_flag_invalid, status);
B
bellard 已提交
6753 6754 6755 6756 6757 6758 6759
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6760
            && (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6761 6762 6763 6764 6765 6766 6767 6768
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

6769 6770
/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot
6771 6772 6773
| 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.
6774 6775
*----------------------------------------------------------------------------*/

6776
int float128_unordered(float128 a, float128 b, float_status *status)
6777 6778 6779 6780 6781 6782
{
    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
P
Peter Maydell 已提交
6783
        float_raise(float_flag_invalid, status);
6784 6785 6786 6787 6788
        return 1;
    }
    return 0;
}

B
bellard 已提交
6789 6790
/*----------------------------------------------------------------------------
| Returns 1 if the quadruple-precision floating-point value `a' is equal to
6791 6792 6793
| 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
6794 6795
*----------------------------------------------------------------------------*/

6796
int float128_eq_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6797 6798 6799 6800 6801 6802 6803
{

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6804 6805
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6806
            float_raise(float_flag_invalid, status);
6807
        }
B
bellard 已提交
6808 6809 6810 6811 6812 6813
        return 0;
    }
    return
           ( a.low == b.low )
        && (    ( a.high == b.high )
             || (    ( a.low == 0 )
6814
                  && ( (uint64_t) ( ( a.high | b.high )<<1 ) == 0 ) )
B
bellard 已提交
6815 6816 6817 6818 6819 6820 6821 6822 6823 6824 6825
           );

}

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

6826
int float128_le_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6827 6828 6829 6830 6831 6832 6833 6834
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6835 6836
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6837
            float_raise(float_flag_invalid, status);
B
bellard 已提交
6838 6839 6840 6841 6842 6843 6844 6845
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6846
            || (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6847 6848 6849 6850 6851 6852 6853 6854 6855 6856 6857 6858 6859 6860 6861
                 == 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.
*----------------------------------------------------------------------------*/

6862
int float128_lt_quiet(float128 a, float128 b, float_status *status)
B
bellard 已提交
6863 6864 6865 6866 6867 6868 6869 6870
{
    flag aSign, bSign;

    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6871 6872
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6873
            float_raise(float_flag_invalid, status);
B
bellard 已提交
6874 6875 6876 6877 6878 6879 6880 6881
        }
        return 0;
    }
    aSign = extractFloat128Sign( a );
    bSign = extractFloat128Sign( b );
    if ( aSign != bSign ) {
        return
               aSign
6882
            && (    ( ( (uint64_t) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
B
bellard 已提交
6883 6884 6885 6886 6887 6888 6889 6890
                 != 0 );
    }
    return
          aSign ? lt128( b.high, b.low, a.high, a.low )
        : lt128( a.high, a.low, b.high, b.low );

}

6891 6892 6893 6894 6895 6896 6897
/*----------------------------------------------------------------------------
| 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.
*----------------------------------------------------------------------------*/

6898
int float128_unordered_quiet(float128 a, float128 b, float_status *status)
6899 6900 6901 6902 6903 6904
{
    if (    (    ( extractFloat128Exp( a ) == 0x7FFF )
              && ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) )
         || (    ( extractFloat128Exp( b ) == 0x7FFF )
              && ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )
       ) {
6905 6906
        if (float128_is_signaling_nan(a, status)
         || float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6907
            float_raise(float_flag_invalid, status);
6908 6909 6910 6911 6912 6913
        }
        return 1;
    }
    return 0;
}

6914 6915
static inline int floatx80_compare_internal(floatx80 a, floatx80 b,
                                            int is_quiet, float_status *status)
6916 6917 6918
{
    flag aSign, bSign;

6919 6920 6921 6922
    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return float_relation_unordered;
    }
6923 6924 6925 6926 6927
    if (( ( extractFloatx80Exp( a ) == 0x7fff ) &&
          ( extractFloatx80Frac( a )<<1 ) ) ||
        ( ( extractFloatx80Exp( b ) == 0x7fff ) &&
          ( extractFloatx80Frac( b )<<1 ) )) {
        if (!is_quiet ||
6928 6929
            floatx80_is_signaling_nan(a, status) ||
            floatx80_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6930
            float_raise(float_flag_invalid, status);
6931 6932 6933 6934 6935 6936 6937 6938 6939 6940 6941 6942 6943 6944 6945 6946 6947 6948 6949 6950 6951 6952 6953
        }
        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 ) ));
        }
    }
}

6954
int floatx80_compare(floatx80 a, floatx80 b, float_status *status)
6955
{
P
Peter Maydell 已提交
6956
    return floatx80_compare_internal(a, b, 0, status);
6957 6958
}

6959
int floatx80_compare_quiet(floatx80 a, floatx80 b, float_status *status)
6960
{
P
Peter Maydell 已提交
6961
    return floatx80_compare_internal(a, b, 1, status);
6962 6963
}

6964 6965
static inline int float128_compare_internal(float128 a, float128 b,
                                            int is_quiet, float_status *status)
B
blueswir1 已提交
6966 6967 6968 6969 6970 6971 6972 6973
{
    flag aSign, bSign;

    if (( ( extractFloat128Exp( a ) == 0x7fff ) &&
          ( extractFloat128Frac0( a ) | extractFloat128Frac1( a ) ) ) ||
        ( ( extractFloat128Exp( b ) == 0x7fff ) &&
          ( extractFloat128Frac0( b ) | extractFloat128Frac1( b ) ) )) {
        if (!is_quiet ||
6974 6975
            float128_is_signaling_nan(a, status) ||
            float128_is_signaling_nan(b, status)) {
P
Peter Maydell 已提交
6976
            float_raise(float_flag_invalid, status);
B
blueswir1 已提交
6977 6978 6979 6980 6981 6982 6983 6984 6985 6986 6987 6988 6989 6990 6991 6992 6993 6994 6995 6996 6997
        }
        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 ) ));
        }
    }
}

6998
int float128_compare(float128 a, float128 b, float_status *status)
B
blueswir1 已提交
6999
{
P
Peter Maydell 已提交
7000
    return float128_compare_internal(a, b, 0, status);
B
blueswir1 已提交
7001 7002
}

7003
int float128_compare_quiet(float128 a, float128 b, float_status *status)
B
blueswir1 已提交
7004
{
P
Peter Maydell 已提交
7005
    return float128_compare_internal(a, b, 1, status);
B
blueswir1 已提交
7006 7007
}

7008
floatx80 floatx80_scalbn(floatx80 a, int n, float_status *status)
P
pbrook 已提交
7009 7010
{
    flag aSign;
7011
    int32_t aExp;
7012
    uint64_t aSig;
P
pbrook 已提交
7013

7014 7015 7016 7017
    if (floatx80_invalid_encoding(a)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
P
pbrook 已提交
7018 7019 7020 7021
    aSig = extractFloatx80Frac( a );
    aExp = extractFloatx80Exp( a );
    aSign = extractFloatx80Sign( a );

7022 7023
    if ( aExp == 0x7FFF ) {
        if ( aSig<<1 ) {
P
Peter Maydell 已提交
7024
            return propagateFloatx80NaN(a, a, status);
7025
        }
P
pbrook 已提交
7026 7027
        return a;
    }
7028

7029 7030 7031 7032 7033 7034
    if (aExp == 0) {
        if (aSig == 0) {
            return a;
        }
        aExp++;
    }
7035

7036 7037 7038 7039 7040 7041
    if (n > 0x10000) {
        n = 0x10000;
    } else if (n < -0x10000) {
        n = -0x10000;
    }

P
pbrook 已提交
7042
    aExp += n;
7043 7044
    return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision,
                                         aSign, aExp, aSig, 0, status);
P
pbrook 已提交
7045 7046
}

7047
float128 float128_scalbn(float128 a, int n, float_status *status)
P
pbrook 已提交
7048 7049
{
    flag aSign;
7050
    int32_t aExp;
7051
    uint64_t aSig0, aSig1;
P
pbrook 已提交
7052 7053 7054 7055 7056 7057

    aSig1 = extractFloat128Frac1( a );
    aSig0 = extractFloat128Frac0( a );
    aExp = extractFloat128Exp( a );
    aSign = extractFloat128Sign( a );
    if ( aExp == 0x7FFF ) {
7058
        if ( aSig0 | aSig1 ) {
P
Peter Maydell 已提交
7059
            return propagateFloat128NaN(a, a, status);
7060
        }
P
pbrook 已提交
7061 7062
        return a;
    }
7063
    if (aExp != 0) {
7064
        aSig0 |= LIT64( 0x0001000000000000 );
7065
    } else if (aSig0 == 0 && aSig1 == 0) {
7066
        return a;
7067 7068 7069
    } else {
        aExp++;
    }
7070

7071 7072 7073 7074 7075 7076
    if (n > 0x10000) {
        n = 0x10000;
    } else if (n < -0x10000) {
        n = -0x10000;
    }

7077 7078
    aExp += n - 1;
    return normalizeRoundAndPackFloat128( aSign, aExp, aSig0, aSig1
P
Peter Maydell 已提交
7079
                                         , status);
P
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7080 7081

}