1  /* Set the FPU control word.
       2     Copyright (C) 1996-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library.  If not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <math.h>
      20  #include <fpu_control.h>
      21  #include <arm-features.h>
      22  
      23  
      24  void
      25  __setfpucw (fpu_control_t set)
      26  {
      27    fpu_control_t fpscr, new_fpscr;
      28  
      29    /* Do nothing if a VFP unit isn't present.  */
      30    if (!ARM_HAVE_VFP)
      31      return;
      32  
      33    _FPU_GETCW (fpscr);
      34  
      35    /* Preserve the reserved bits, and set the rest as the user
      36       specified (or the default, if the user gave zero).  */
      37    new_fpscr = fpscr & _FPU_RESERVED;
      38    new_fpscr |= set & ~_FPU_RESERVED;
      39  
      40    /* Write FPSCR if changed.  */
      41    if (new_fpscr != fpscr)
      42      _FPU_SETCW (fpscr);
      43  }