/*      $NetBSD: fpsetround.c,v 1.9 2024/03/20 06:15:39 rillig Exp $    */

/*
 * Written by J.T. Conklin, Apr 10, 1995
 * Public domain.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: fpsetround.c,v 1.9 2024/03/20 06:15:39 rillig Exp $");
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"

#include <sys/types.h>
#include <ieeefp.h>

#ifdef __weak_alias
__weak_alias(fpsetround,_fpsetround)
#endif

#ifdef SOFTFLOATSPARC64_FOR_GCC
extern fp_rnd _softfloat_float_rounding_mode;
#endif

fp_rnd
fpsetround(fp_rnd rnd_dir)
{
        fp_rnd old;
        fp_rnd new;

        __asm("st %%fsr,%0" : "=m" (*&old));

#ifdef SOFTFLOATSPARC64_FOR_GCC
        _softfloat_float_rounding_mode = rnd_dir;
#endif

        new = old;
        new &= ~(0x03U << 30);
        new |= ((rnd_dir & 0x03U) << 30);

        __asm("ld %0,%%fsr" : : "m" (*&new));

        return ((uint32_t)old >> 30) & 0x03;
}