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authorBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2008-01-19 15:23:14 +0000
committerBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2008-01-19 15:23:14 +0000
commitbce5bba7a01fb090f67fec5f79218c505c841af3 (patch)
treee7d7dfc12cae1f1474800071fbc4633fa509ef6e /libm/i386/fesetenv.c
parentd22976dd5e16e8719abd5c542e17427eeece7ff6 (diff)
- add C99 floating point environment, rounding and exception handling functions
for i386. UCLIBC_HAS_FENV
Diffstat (limited to 'libm/i386/fesetenv.c')
-rw-r--r--libm/i386/fesetenv.c80
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)