diff options
Diffstat (limited to 'sysdeps/x86_64/fpu/fesetenv.c')
-rw-r--r-- | sysdeps/x86_64/fpu/fesetenv.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/sysdeps/x86_64/fpu/fesetenv.c b/sysdeps/x86_64/fpu/fesetenv.c new file mode 100644 index 0000000000..4527b16ed9 --- /dev/null +++ b/sysdeps/x86_64/fpu/fesetenv.c @@ -0,0 +1,89 @@ +/* Install given floating-point environment. + Copyright (C) 2001 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <fenv.h> +#include <assert.h> + + +int +fesetenv (const fenv_t *envp) +{ + fenv_t temp; + + /* 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\n" + "stmxcsr %1" : "=m" (*&temp), "=m" (*&temp.__mxcsr)); + + 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; + /* Set mask for SSE MXCSR. */ + temp.__mxcsr |= (FE_ALL_EXCEPT << 7); + /* Set rounding to FE_TOWARDZERO. */ + temp.__mxcsr &= ~(FE_TOWARDZERO << 3); + /* Disable exceptions. */ + temp.__mxcsr &= ~FE_ALL_EXCEPT; + } + 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; + /* Set mask for SSE MXCSR. */ + temp.__mxcsr &= ~(FE_ALL_EXCEPT << 7); + /* Set rounding to FE_TOWARDZERO. */ + temp.__mxcsr &= ~(FE_TOWARDZERO << 3); + /* Disable exceptions. */ + temp.__mxcsr &= ~FE_ALL_EXCEPT; + } + 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; + temp.__mxcsr = envp->__mxcsr; + } + + __asm__ ("fldenv %0\n" + "ldmxcsr %1" : : "m" (temp), "m" (temp.__mxcsr)); + + /* Success. */ + return 0; +} |