From bce5bba7a01fb090f67fec5f79218c505c841af3 Mon Sep 17 00:00:00 2001 From: Bernhard Reutner-Fischer Date: Sat, 19 Jan 2008 15:23:14 +0000 Subject: - add C99 floating point environment, rounding and exception handling functions for i386. UCLIBC_HAS_FENV --- libm/i386/fclrexcpt.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 libm/i386/fclrexcpt.c (limited to 'libm/i386/fclrexcpt.c') diff --git a/libm/i386/fclrexcpt.c b/libm/i386/fclrexcpt.c new file mode 100644 index 000000000..a34060ce8 --- /dev/null +++ b/libm/i386/fclrexcpt.c @@ -0,0 +1,61 @@ +/* Clear given exceptions in current floating-point environment. + Copyright (C) 1997,99,2000, 2001, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 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 +#include + +int +feclearexcept (int excepts) +{ + fenv_t temp; + + /* 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)); + +#if 0 + /* If the CPU supports SSE, we clear the MXCSR as well. */ + if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0) + { + unsigned int xnew_exc; + + /* Get the current MXCSR. */ + __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc)); + + /* Clear the relevant bits. */ + xnew_exc &= ~excepts; + + /* Put the new data in effect. */ + __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc)); + } +#endif + + /* Success. */ + return 0; +} -- cgit v1.2.3