nds32: add support for new architecture

Add support for Andes Technology NDS32 architecture.
See here http://www.andestech.com/en/index/index.htm for more
informaton. Verification of the port from an older uClibc
port was done on a sponsored AG101p board.

The testsuite only has 5 errors, three are related to
an existing bug in dlclose() with LT.old, also happening
on cris32 and m68k.

Failures to fallocate/posix_fallocate are unresolved.

Thanks to Andes Technology sponsoring the hardware and
being very helpful while doing the uClibc-ng porting.

Signed-off-by: Waldemar Brodkorb <wbx@uclibc-ng.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/nds32/sigrestorer.S b/libc/sysdeps/linux/nds32/sigrestorer.S
new file mode 100644
index 000000000..bf6188656
--- /dev/null
+++ b/libc/sysdeps/linux/nds32/sigrestorer.S
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2016 Andes Technology, Inc.
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* Copyright (C) 1999 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#include <sys/syscall.h>
+
+/* If no SA_RESTORER function was specified by the application we use
+   one of these.  This avoids the need for the kernel to synthesise a return
+   instruction on the stack, which would involve expensive cache flushes. */
+
+ENTRY(__default_sa_restorer)
+	/* DO NOT SAVE r7 INTO STACK, THIS SYSCALL NEVER RETURN */
+	syscall	SYS_ify(sigreturn)
+END(__default_sa_restorer)
+
+#ifdef __NR_rt_sigreturn
+
+ENTRY(__default_rt_sa_restorer)
+	/* DO NOT SAVE r7 INTO STACK, THIS SYSCALL NEVER RETURN */
+	syscall	SYS_ify(rt_sigreturn)
+END(__default_rt_sa_restorer)
+
+#endif