diff options
author | Waldemar Brodkorb <wbx@uclibc-ng.org> | 2017-12-03 21:12:34 +0100 |
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committer | Waldemar Brodkorb <wbx@uclibc-ng.org> | 2017-12-03 21:12:34 +0100 |
commit | edce88cfef2f2a62647c2ab9536ca29694fab292 (patch) | |
tree | 5cfc13c44a91bb8b983ee137de38e136289db81e /libm/x86_64/fclrexcpt.c | |
parent | c69db851309995c525b3993a10dc13dabdeb7b33 (diff) |
x86_64: add fenv support from glibc
Diffstat (limited to 'libm/x86_64/fclrexcpt.c')
-rw-r--r-- | libm/x86_64/fclrexcpt.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/libm/x86_64/fclrexcpt.c b/libm/x86_64/fclrexcpt.c new file mode 100644 index 000000000..ddd4d736c --- /dev/null +++ b/libm/x86_64/fclrexcpt.c @@ -0,0 +1,50 @@ +/* Clear given exceptions in current floating-point environment. + Copyright (C) 2001-2017 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 + <http://www.gnu.org/licenses/>. */ + +#include <fenv.h> + +int +feclearexcept (int excepts) +{ + fenv_t temp; + unsigned int mxcsr; + + /* Mask out unsupported bits/exceptions. */ + excepts &= FE_ALL_EXCEPT; + + /* Bah, we have to clear selected exceptions. Since there is no + `fldsw' instruction we have to do it the hard way. */ + __asm__ ("fnstenv %0" : "=m" (*&temp)); + + /* Clear the relevant bits. */ + temp.__status_word &= excepts ^ FE_ALL_EXCEPT; + + /* Put the new data in effect. */ + __asm__ ("fldenv %0" : : "m" (*&temp)); + + /* And the same procedure for SSE. */ + __asm__ ("stmxcsr %0" : "=m" (*&mxcsr)); + + /* Clear the relevant bits. */ + mxcsr &= ~excepts; + + /* And put them into effect. */ + __asm__ ("ldmxcsr %0" : : "m" (*&mxcsr)); + + /* Success. */ + return 0; +} |