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-rw-r--r--REORG.TODO/sysdeps/arm/feupdateenv.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/arm/feupdateenv.c b/REORG.TODO/sysdeps/arm/feupdateenv.c
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+++ b/REORG.TODO/sysdeps/arm/feupdateenv.c
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+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1997-2017 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+#include <arm-features.h>
+
+
+int
+__feupdateenv (const fenv_t *envp)
+{
+  fpu_control_t fpscr, new_fpscr, updated_fpscr;
+  int excepts;
+
+  /* Fail if a VFP unit isn't present.  */
+  if (!ARM_HAVE_VFP)
+    return 1;
+
+  _FPU_GETCW (fpscr);
+  excepts = fpscr & FE_ALL_EXCEPT;
+
+  if ((envp != FE_DFL_ENV) && (envp != FE_NOMASK_ENV))
+    {
+      /* Merge current exception flags with the saved fenv.  */
+      new_fpscr = envp->__cw | excepts;
+
+      /* Write new FPSCR if different (ignoring NZCV flags).  */
+      if (((fpscr ^ new_fpscr) & ~_FPU_MASK_NZCV) != 0)
+	_FPU_SETCW (new_fpscr);
+
+      /* Raise the exceptions if enabled in the new FP state.  */
+      if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT))
+	return __feraiseexcept (excepts);
+
+      return 0;
+    }
+
+  /* Preserve the reserved FPSCR flags.  */
+  new_fpscr = fpscr & (_FPU_RESERVED | FE_ALL_EXCEPT);
+  new_fpscr |= (envp == FE_DFL_ENV) ? _FPU_DEFAULT : _FPU_IEEE;
+
+  if (((new_fpscr ^ fpscr) & ~_FPU_MASK_NZCV) != 0)
+    {
+      _FPU_SETCW (new_fpscr);
+
+      /* Not all VFP architectures support trapping exceptions, so
+	 test whether the relevant bits were set and fail if not.  */
+      _FPU_GETCW (updated_fpscr);
+
+      if (new_fpscr & ~updated_fpscr)
+	return 1;
+    }
+
+  /* Raise the exceptions if enabled in the new FP state.  */
+  if (excepts & (new_fpscr >> FE_EXCEPT_SHIFT))
+    return __feraiseexcept (excepts);
+
+  return 0;
+}
+libm_hidden_def (__feupdateenv)
+weak_alias (__feupdateenv, feupdateenv)
+libm_hidden_weak (feupdateenv)