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Diffstat (limited to 'sysdeps/x86_64/fpu/fesetenv.c')
-rw-r--r--sysdeps/x86_64/fpu/fesetenv.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/sysdeps/x86_64/fpu/fesetenv.c b/sysdeps/x86_64/fpu/fesetenv.c
new file mode 100644
index 0000000000..4527b16ed9
--- /dev/null
+++ b/sysdeps/x86_64/fpu/fesetenv.c
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+/* Install given floating-point environment.
+ Copyright (C) 2001 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ 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>
+
+
+int
+fesetenv (const fenv_t *envp)
+{
+ fenv_t temp;
+
+ /* 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\n"
+ "stmxcsr %1" : "=m" (*&temp), "=m" (*&temp.__mxcsr));
+
+ 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;
+ /* Set mask for SSE MXCSR. */
+ temp.__mxcsr |= (FE_ALL_EXCEPT << 7);
+ /* Set rounding to FE_TOWARDZERO. */
+ temp.__mxcsr &= ~(FE_TOWARDZERO << 3);
+ /* Disable exceptions. */
+ temp.__mxcsr &= ~FE_ALL_EXCEPT;
+ }
+ 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;
+ /* Set mask for SSE MXCSR. */
+ temp.__mxcsr &= ~(FE_ALL_EXCEPT << 7);
+ /* Set rounding to FE_TOWARDZERO. */
+ temp.__mxcsr &= ~(FE_TOWARDZERO << 3);
+ /* Disable exceptions. */
+ temp.__mxcsr &= ~FE_ALL_EXCEPT;
+ }
+ 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;
+ temp.__mxcsr = envp->__mxcsr;
+ }
+
+ __asm__ ("fldenv %0\n"
+ "ldmxcsr %1" : : "m" (temp), "m" (temp.__mxcsr));
+
+ /* Success. */
+ return 0;
+}