diff options
Diffstat (limited to 'libm/i386/fesetenv.c')
-rw-r--r-- | libm/i386/fesetenv.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/libm/i386/fesetenv.c b/libm/i386/fesetenv.c new file mode 100644 index 000000000..fdb4fcc92 --- /dev/null +++ b/libm/i386/fesetenv.c @@ -0,0 +1,80 @@ +/* Install given floating-point environment. + Copyright (C) 1997,98,99,2000,01,02 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <fenv.h> +#include <assert.h> + +libm_hidden_proto(fesetenv) + +int +fesetenv (const fenv_t *envp) +{ + fenv_t temp; + + /* The memory block used by fstenv/fldenv has a size of 28 bytes. */ + assert (sizeof (fenv_t) == 28); + + /* Install the environment specified by ENVP. But there are a few + values which we do not want to come from the saved environment. + Therefore, we get the current environment and replace the values + we want to use from the environment specified by the parameter. */ + __asm__ ("fnstenv %0" : "=m" (*&temp)); + + if (envp == FE_DFL_ENV) + { + temp.__control_word |= FE_ALL_EXCEPT; + temp.__control_word &= ~FE_TOWARDZERO; + temp.__status_word &= ~FE_ALL_EXCEPT; + temp.__eip = 0; + temp.__cs_selector = 0; + temp.__opcode = 0; + temp.__data_offset = 0; + temp.__data_selector = 0; + } + else if (envp == FE_NOMASK_ENV) + { + temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO); + temp.__status_word &= ~FE_ALL_EXCEPT; + temp.__eip = 0; + temp.__cs_selector = 0; + temp.__opcode = 0; + temp.__data_offset = 0; + temp.__data_selector = 0; + } + else + { + temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO); + temp.__control_word |= (envp->__control_word + & (FE_ALL_EXCEPT | FE_TOWARDZERO)); + temp.__status_word &= ~FE_ALL_EXCEPT; + temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT; + temp.__eip = envp->__eip; + temp.__cs_selector = envp->__cs_selector; + temp.__opcode = envp->__opcode; + temp.__data_offset = envp->__data_offset; + temp.__data_selector = envp->__data_selector; + } + + __asm__ ("fldenv %0" : : "m" (temp)); + + /* Success. */ + return 0; +} +libm_hidden_def(fesetenv) |