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, 38 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/nds32/swapcontext.c b/libc/sysdeps/linux/nds32/swapcontext.c
new file mode 100644
index 000000000..310923f0d
--- /dev/null
+++ b/libc/sysdeps/linux/nds32/swapcontext.c
@@ -0,0 +1,38 @@
+/* Copyright (C) 2001-2013 Free Software Foundation, Inc.
+     Contributed by David Mosberger-Tang <davidm@hpl.hp.com>.
+
+   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 <ucontext.h>
+
+struct rv
+  {
+    long retval;
+    long first_return;
+  };
+
+extern struct rv __getcontext (ucontext_t *__ucp);
+extern int __setcontext (const ucontext_t *__ucp);
+
+int
+__swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
+{
+  struct rv rv = __getcontext (oucp);
+  if (rv.first_return)
+    __setcontext (ucp);
+  return 0;
+}
+
+weak_alias (__swapcontext, swapcontext)