source: mainline/uspace/lib/c/include/ieee_double.h@ cd1e3fc0

/*
 * SPDX-FileCopyrightText: 2012 Adam Hraska
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef IEEE_DOUBLE_H_
#define IEEE_DOUBLE_H_

#include <stdint.h>
#include <stdbool.h>

/** Represents a non-negative floating point number: significand * 2^exponent */
typedef struct fp_num_t_tag {
        /** Significand (aka mantissa). */
        uint64_t significand;
        /** Binary exponent. */
        int exponent;
} fp_num_t;

/** Double number description according to IEEE 754. */
typedef struct ieee_double_t_tag {
        /** The number is a NaN or infinity. */
        bool is_special;
        /** Not a number. */
        bool is_nan;
        bool is_negative;
        /** The number denoted infinity. */
        bool is_infinity;
        /** The number could not be represented as a normalized double. */
        bool is_denormal;
        /**
         * The predecessor double is closer than the successor. This happens
         * if a normal number is of the form 2^k and it is not the smallest
         * normal number.
         */
        bool is_accuracy_step;
        /**
         * If !is_special the double's value is:
         *   pos_val.significand * 2^pos_val.exponent
         */
        fp_num_t pos_val;
} ieee_double_t;

extern ieee_double_t extract_ieee_double(double);

#endif