diff options
Diffstat (limited to 'libm/arm/fesetenv.c')
| -rw-r--r-- | libm/arm/fesetenv.c | 62 | 
1 files changed, 62 insertions, 0 deletions
| diff --git a/libm/arm/fesetenv.c b/libm/arm/fesetenv.c new file mode 100644 index 000000000..4675dbe88 --- /dev/null +++ b/libm/arm/fesetenv.c @@ -0,0 +1,62 @@ +/* Install given floating-point environment. +   Copyright (C) 2004-2025 Free Software Foundation, Inc. + +   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 +   <https://www.gnu.org/licenses/>.  */ + +#include <fenv.h> +#include <fpu_control.h> +#include "arm-features.h" + + +int +fesetenv (const fenv_t *envp) +{ +  fpu_control_t fpscr, new_fpscr, updated_fpscr; + +  /* Fail if a VFP unit isn't present.  */ +  if (!ARM_HAVE_VFP) +    return 1; + +  _FPU_GETCW (fpscr); + +  if ((envp != FE_DFL_ENV) && (envp != FE_NOMASK_ENV)) +    { +      /* The new FPSCR is valid, so don't merge the reserved flags.  */ +      new_fpscr = envp->__cw; + +      /* Write new FPSCR if different (ignoring NZCV flags).  */ +      if (((fpscr ^ new_fpscr) & ~_FPU_MASK_NZCV) != 0) +	_FPU_SETCW (new_fpscr); + +      return 0; +    } + +  /* Preserve the reserved FPSCR flags.  */ +  new_fpscr = fpscr & _FPU_RESERVED; +  new_fpscr |= (envp == FE_DFL_ENV) ? _FPU_DEFAULT : _FPU_IEEE; + +  if (((new_fpscr ^ fpscr) & ~_FPU_MASK_NZCV) != 0) +    { +      _FPU_SETCW (new_fpscr); + +      /* Not all VFP architectures support trapping exceptions, so +	 test whether the relevant bits were set and fail if not.  */ +      _FPU_GETCW (updated_fpscr); + +      return new_fpscr & ~updated_fpscr; +    } + +  return 0; +} | 
