/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

#ifndef _FENV_H_
#define _FENV_H_

#include <sys/cdefs.h>
#include <sys/_types.h>

#ifndef __fenv_static
#define __fenv_static   static
#endif

typedef __uint32_t      fenv_t;
typedef __uint32_t      fexcept_t;

/* Exception flags */
#define FE_INVALID      0x0001
#define FE_DIVBYZERO    0x0002
#define FE_OVERFLOW     0x0004
#define FE_UNDERFLOW    0x0008
#define FE_INEXACT      0x0010
#ifdef __ARM_PCS_VFP
#define FE_DENORMAL     0x0080
#define FE_ALL_EXCEPT   (FE_DIVBYZERO | FE_INEXACT | \
                         FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW | FE_DENORMAL)
#else
#define FE_ALL_EXCEPT   (FE_DIVBYZERO | FE_INEXACT | \
                         FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
#endif

/* Rounding modes */
#define VFP_FE_TONEAREST        0x00000000
#define VFP_FE_UPWARD           0x00400000
#define VFP_FE_DOWNWARD         0x00800000
#define VFP_FE_TOWARDZERO       0x00c00000

#ifdef __ARM_PCS_VFP
#define FE_TONEAREST    VFP_FE_TONEAREST
#define FE_UPWARD       VFP_FE_UPWARD
#define FE_DOWNWARD     VFP_FE_DOWNWARD
#define FE_TOWARDZERO   VFP_FE_TOWARDZERO
#else
#define FE_TONEAREST    0x0000
#define FE_TOWARDZERO   0x0001
#define FE_UPWARD       0x0002
#define FE_DOWNWARD     0x0003
#endif
#define _ROUND_MASK     (FE_TONEAREST | FE_DOWNWARD | \
                         FE_UPWARD | FE_TOWARDZERO)
__BEGIN_DECLS

/* Default floating-point environment */
extern const fenv_t     __fe_dfl_env;
#define FE_DFL_ENV      (&__fe_dfl_env)

/* We need to be able to map status flag positions to mask flag positions */
#ifndef __ARM_PCS_VFP
#define _FPUSW_SHIFT    16
#define _ENABLE_MASK    (FE_ALL_EXCEPT << _FPUSW_SHIFT)
#endif

#ifndef __ARM_PCS_VFP

int feclearexcept(int __excepts);
int fegetexceptflag(fexcept_t *__flagp, int __excepts);
int fesetexceptflag(const fexcept_t *__flagp, int __excepts);
int feraiseexcept(int __excepts);
int fetestexcept(int __excepts);
int fegetround(void);
int fesetround(int __round);
int fegetenv(fenv_t *__envp);
int feholdexcept(fenv_t *__envp);
int fesetenv(const fenv_t *__envp);
int feupdateenv(const fenv_t *__envp);
#if __BSD_VISIBLE
int feenableexcept(int __mask);
int fedisableexcept(int __mask);
int fegetexcept(void);
#endif

#else   /* __ARM_PCS_VFP */

#define vmrs_fpscr(__r) __asm __volatile("vmrs %0, fpscr" : "=&r"(__r))
#define vmsr_fpscr(__r) __asm __volatile("vmsr fpscr, %0" : : "r"(__r))

#define _FPU_MASK_SHIFT 8

int feclearexcept(int);
int fegetexceptflag(fexcept_t *, int);
int fesetexceptflag(const fexcept_t *, int);
int feraiseexcept(int);
int fetestexcept(int);
int fegetround(void);
int fesetround(int);
int fegetenv(fenv_t *);
int feholdexcept(fenv_t *);
int fesetenv(const fenv_t *);
int feupdateenv(const fenv_t *);
int fegetexcept(void);
#if __BSD_VISIBLE
int feenableexcept(int);
int fedisableexcept(int);
int fegetexcept(void);
#endif

#define feclearexcept(a)        __feclearexcept_int(a)
#define fegetexceptflag(e, a)   __fegetexceptflag_int(e, a)
#define fesetexceptflag(e, a)   __fesetexceptflag_int(e, a)
#define feraiseexcept(a)        __feraiseexcept_int(a)
#define fetestexcept(a)         __fetestexcept_int(a)
#define fegetround()            __fegetround_int()
#define fesetround(a)           __fesetround_int(a)
#define fegetenv(e)             __fegetenv_int(e)
#define feholdexcept(e)         __feholdexcept_int(e)
#define fesetenv(e)             __fesetenv_int(e)
#define feupdateenv(e)          __feupdateenv_int(e)
#if __BSD_VISIBLE
#define feenableexcept(a)       __feenableexcept_int(a)
#define fedisableexcept(a)      __fedisableexcept_int(a)
#define fegetexcept()           __fegetexcept_int()
#endif

__fenv_static inline int
__feclearexcept_int(int __excepts)
{
        fexcept_t __fpsr;

        vmrs_fpscr(__fpsr);
        __fpsr &= ~__excepts;
        vmsr_fpscr(__fpsr);
        return (0);
}

__fenv_static inline int
__fegetexceptflag_int(fexcept_t *__flagp, int __excepts)
{
        fexcept_t __fpsr;

        vmrs_fpscr(__fpsr);
        *__flagp = __fpsr & __excepts;
        return (0);
}

__fenv_static inline int
__fesetexceptflag_int(const fexcept_t *__flagp, int __excepts)
{
        fexcept_t __fpsr;

        vmrs_fpscr(__fpsr);
        __fpsr &= ~__excepts;
        __fpsr |= *__flagp & __excepts;
        vmsr_fpscr(__fpsr);
        return (0);
}

__fenv_static inline int
__feraiseexcept_int(int __excepts)
{
        fexcept_t __ex = __excepts;

        fesetexceptflag(&__ex, __excepts);      /* XXX */
        return (0);
}

__fenv_static inline int
__fetestexcept_int(int __excepts)
{
        fexcept_t __fpsr;

        vmrs_fpscr(__fpsr);
        return (__fpsr & __excepts);
}

__fenv_static inline int
__fegetround_int(void)
{
        fenv_t __fpsr;

        vmrs_fpscr(__fpsr);
        return (__fpsr & _ROUND_MASK);
}

__fenv_static inline int
__fesetround_int(int __round)
{
        fenv_t __fpsr;

        vmrs_fpscr(__fpsr);
        __fpsr &= ~(_ROUND_MASK);
        __fpsr |= __round;
        vmsr_fpscr(__fpsr);
        return (0);
}

__fenv_static inline int
__fegetenv_int(fenv_t *__envp)
{

        vmrs_fpscr(*__envp);
        return (0);
}

__fenv_static inline int
__feholdexcept_int(fenv_t *__envp)
{
        fenv_t __env;

        vmrs_fpscr(__env);
        *__envp = __env;
        __env &= ~(FE_ALL_EXCEPT);
        vmsr_fpscr(__env);
        return (0);
}

__fenv_static inline int
__fesetenv_int(const fenv_t *__envp)
{

        vmsr_fpscr(*__envp);
        return (0);
}

__fenv_static inline int
__feupdateenv_int(const fenv_t *__envp)
{
        fexcept_t __fpsr;

        vmrs_fpscr(__fpsr);
        vmsr_fpscr(*__envp);
        feraiseexcept(__fpsr & FE_ALL_EXCEPT);
        return (0);
}

#if __BSD_VISIBLE

/* We currently provide no external definitions of the functions below. */

__fenv_static inline int
__feenableexcept_int(int __mask)
{
        fenv_t __old_fpsr, __new_fpsr;

        vmrs_fpscr(__old_fpsr);
        __new_fpsr = __old_fpsr |
            ((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
        vmsr_fpscr(__new_fpsr);
        return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
}

__fenv_static inline int
__fedisableexcept_int(int __mask)
{
        fenv_t __old_fpsr, __new_fpsr;

        vmrs_fpscr(__old_fpsr);
        __new_fpsr = __old_fpsr &
            ~((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
        vmsr_fpscr(__new_fpsr);
        return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
}

__fenv_static inline int
__fegetexcept_int(void)
{
        fenv_t __fpsr;

        vmrs_fpscr(__fpsr);
        return (__fpsr & FE_ALL_EXCEPT);
}

#endif /* __BSD_VISIBLE */

#endif  /* __ARM_PCS_VFP */

__END_DECLS

#endif  /* !_FENV_H_ */