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Diffstat (limited to 'sysdeps/i386/fpu/fesetenv.c')
-rw-r--r--sysdeps/i386/fpu/fesetenv.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/fesetenv.c b/sysdeps/i386/fpu/fesetenv.c
new file mode 100644
index 0000000000..e7300ea1e6
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+++ b/sysdeps/i386/fpu/fesetenv.c
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+/* Install given floating-point environment.
+ Copyright (C) 1997 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. 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>
+
+
+void
+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_TOWARDSZERO;
+ 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_TOWARDSZERO);
+ 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_TOWARDSZERO);
+ temp.control_word |= (envp->control_word
+ & (FE_ALL_EXCEPT | FE_TOWARDSZERO));
+ 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));
+}