nds32: add NPTL/TLS, *context function, libm changes and code cleanup

This commit includes following features.
1. Support NPTL/TLS
2. Add libm function which is used to handle FP rounding and excpetions
   (ex: fclrexcpt,fedisblxcpti,feenablxcpt... )
3. Add *context function for operating user context
   (ex: setcontext,getcontext,makecontext... )
4. Change the return flow from signal handler
5. Cleanup of old code

The testsuite only has 2 errors, tst-cpuclock1 and tst-cputimer1,
which are related to timing accuracy. (math and locale tests are disabled)

Signed-off-by: Vincent Ren-Wei Chen <vincentc@andestech.com>

1 files changed, 79 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/nds32/bits/fenv.h b/libc/sysdeps/linux/nds32/bits/fenv.h
new file mode 100644
index 000000000..010d870f5
--- /dev/null
+++ b/libc/sysdeps/linux/nds32/bits/fenv.h
@@ -0,0 +1,79 @@
+/* Copyright (C) 2004-2012 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#ifndef _FENV_H
+# error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
+#endif
+
+/* Define bits representing exceptions in the FPCSR status word.  */
+enum
+  {
+    FE_INVALID =
+#define FE_INVALID	0x4
+      FE_INVALID,
+    FE_DIVBYZERO =
+#define FE_DIVBYZERO	0x8
+      FE_DIVBYZERO,
+    FE_OVERFLOW =
+#define FE_OVERFLOW	0x10
+      FE_OVERFLOW,
+    FE_UNDERFLOW =
+#define FE_UNDERFLOW	0x20
+      FE_UNDERFLOW,
+    FE_INEXACT =
+#define FE_INEXACT	0x40
+      FE_INEXACT,
+  };
+
+
+/* All supported exceptions.  */
+#define FE_ALL_EXCEPT	\
+	(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT)
+
+/* Define bits representing rounding modes in the FPCSR RM field.  */
+enum
+  {
+    FE_TONEAREST =
+#define FE_TONEAREST    0x0
+      FE_TONEAREST,
+    FE_UPWARD =
+#define FE_UPWARD       0x1
+      FE_UPWARD,
+    FE_DOWNWARD =
+#define FE_DOWNWARD     0x2
+      FE_DOWNWARD,
+    FE_TOWARDZERO =
+#define FE_TOWARDZERO   0x3
+      FE_TOWARDZERO
+  };
+
+/* Type representing exception flags. */
+typedef unsigned int fexcept_t;
+
+/* Type representing floating-point environment.  */
+typedef struct
+  {
+    unsigned int __fpcsr;
+  }
+fenv_t;
+
+/* If the default argument is used we use this value.  */
+#define FE_DFL_ENV	((const fenv_t *) -1l)
+
+#ifdef __USE_GNU
+/* Floating-point environment where none of the exceptions are masked.  */
+# define FE_NOMASK_ENV  ((const fenv_t *) -2)
+#endif