reactos/sdk/lib/crt/math/fabsf.c

/*
 * PROJECT:     ReactOS CRT library
 * LICENSE:     MIT (https://spdx.org/licenses/MIT)
 * PURPOSE:     Portable implementation of fabsf
 * COPYRIGHT:   Copyright 2021 Timo Kreuzer <timo.kreuzer@reactos.org>
 */

#include <math.h>

_Check_return_
float
__cdecl
fabsf(
    _In_ float x)
{
    /* Load the value as uint */
    unsigned int u32 = *(unsigned int*)&x;

    /* Clear the sign bit */
    u32 &= ~(1 << 31);

    /* Check for NAN */
    if (u32 > 0x7F800000)
    {
        /* Set error bit */
        *(unsigned int*)&x |= 0x00400000;
        return x;
    }

    /* Convert back to float */
    return *(float*)&u32;
}