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-rw-r--r--sysdeps/alpha/fpu/fesetenv.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/sysdeps/alpha/fpu/fesetenv.c b/sysdeps/alpha/fpu/fesetenv.c
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+++ b/sysdeps/alpha/fpu/fesetenv.c
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+/* Install given floating-point environment.
+   Copyright (C) 1997-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv_libc.h>
+
+int
+__fesetenv (const fenv_t *envp)
+{
+  unsigned long int fpcr;
+  fenv_t env;
+
+  /* Magic encoding of default values: high bit set (never possible for a
+     user-space address) is not indirect.  And we don't even have to get
+     rid of it since we mask things around just below.  */
+  if ((long int) envp >= 0)
+    env = *envp;
+  else
+    env = (unsigned long int) envp;
+
+  /* Reset the rounding mode with the hardware fpcr.  Note that the following
+     system call is an implied trap barrier for our modification.  */
+  __asm__ __volatile__ ("excb; mf_fpcr %0" : "=f" (fpcr));
+  fpcr = (fpcr & ~FPCR_ROUND_MASK) | (env & FPCR_ROUND_MASK);
+  __asm__ __volatile__ ("mt_fpcr %0" : : "f" (fpcr));
+
+  /* Reset the exception status and mask with the kernel's FP code.  */
+  __ieee_set_fp_control (env & SWCR_ALL_MASK);
+
+  /* Success.  */
+  return 0;
+}
+
+#include <shlib-compat.h>
+#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
+strong_alias (__fesetenv, __old_fesetenv)
+compat_symbol (libm, __old_fesetenv, fesetenv, GLIBC_2_1);
+#endif
+
+libm_hidden_ver (__fesetenv, fesetenv)
+versioned_symbol (libm, __fesetenv, fesetenv, GLIBC_2_2);