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/feenablxcpt.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 libm/i386/feenablxcpt.c (limited to 'libm/i386/feenablxcpt.c') diff --git a/libm/i386/feenablxcpt.c b/libm/i386/feenablxcpt.c new file mode 100644 index 000000000..174f9f1ad --- /dev/null +++ b/libm/i386/feenablxcpt.c @@ -0,0 +1,55 @@ +/* Enable floating-point exceptions. + Copyright (C) 1999, 2000, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Andreas Jaeger , 1999. + + 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 +feenableexcept (int excepts) +{ + unsigned short int new_exc; + unsigned short int old_exc; + + /* Get the current control word. */ + __asm__ ("fstcw %0" : "=m" (*&new_exc)); + + excepts &= FE_ALL_EXCEPT; + old_exc = (~new_exc) & FE_ALL_EXCEPT; + + new_exc &= ~excepts; + __asm__ ("fldcw %0" : : "m" (*&new_exc)); + +#if 0 + /* If the CPU supports SSE we set the MXCSR as well. */ + if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0) + { + unsigned int xnew_exc; + + /* Get the current control word. */ + __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc)); + + xnew_exc &= ~(excepts << 7); + + __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc)); + } +#endif + + return old_exc; +} -- cgit v1.2.3