/* Install given floating-point control modes.  x86_64 version.

   Copyright (C) 2016-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <fenv.h>

#include <fpu_control.h>

/* All exceptions, including the x86-specific "denormal operand"

   exception.  */

#define FE_ALL_EXCEPT_X86 (FE_ALL_EXCEPT | __FE_DENORM)

int

fesetmode (const femode_t *modep)

{

  fpu_control_t cw;

  unsigned int mxcsr;

  __asm__ ("stmxcsr %0" : "=m" (mxcsr));

  /* Preserve SSE exception flags but restore other state in

     MXCSR.  */

  mxcsr &= FE_ALL_EXCEPT_X86;

  if (modep == FE_DFL_MODE)

    {

      cw = _FPU_DEFAULT;

      /* Default MXCSR state has all bits zero except for those

	 masking exceptions.  */

      mxcsr |= FE_ALL_EXCEPT_X86 << 7;

    }

  else

    {

      cw = modep->__control_word;

      mxcsr |= modep->__mxcsr & ~FE_ALL_EXCEPT_X86;

    }

  _FPU_SETCW (cw);

  __asm__ ("ldmxcsr %0" : : "m" (mxcsr));

  return 0;

}