- add C99 floating point environment, rounding and exception handling functions

  for i386. UCLIBC_HAS_FENV

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)