nptl: Add <thread_pointer.h> for defining __thread_pointer

<tls.h> already contains a definition that is quite similar,
but it is not consistent across architectures.

Only architectures for which rseq support is added are covered.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/sysdeps/nptl/thread_pointer.h b/sysdeps/nptl/thread_pointer.h
new file mode 100644
index 0000000000..92f2f3093e
--- /dev/null
+++ b/sysdeps/nptl/thread_pointer.h
@@ -0,0 +1,28 @@
+/* __thread_pointer definition.  Generic version.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_THREAD_POINTER_H
+#define _SYS_THREAD_POINTER_H
+
+static inline void *
+__thread_pointer (void)
+{
+  return __builtin_thread_pointer ();
+}
+
+#endif /* _SYS_THREAD_POINTER_H */