LoongArch: Add support for TLS Descriptors

This is mostly based on AArch64 and RISC-V implementation.

Add R_LARCH_TLS_DESC32 and R_LARCH_TLS_DESC64 relocations.

For _dl_tlsdesc_dynamic function slow path, temporarily save and restore
all vector registers.

1 files changed, 49 insertions, 0 deletions

diff --git a/sysdeps/loongarch/dl-tlsdesc.h b/sysdeps/loongarch/dl-tlsdesc.h
new file mode 100644
index 0000000000..ff8c69cb93
--- /dev/null
+++ b/sysdeps/loongarch/dl-tlsdesc.h
@@ -0,0 +1,49 @@
+/* Thread-local storage descriptor handling in the ELF dynamic linker.
+   LoongArch version.
+   Copyright (C) 2024 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 _DL_TLSDESC_H
+#define _DL_TLSDESC_H
+
+#include <dl-tls.h>
+
+/* Type used to represent a TLS descriptor in the GOT.  */
+struct tlsdesc
+{
+  ptrdiff_t (*entry) (struct tlsdesc *);
+  void *arg;
+};
+
+/* Type used as the argument in a TLS descriptor for a symbol that
+   needs dynamic TLS offsets.  */
+struct tlsdesc_dynamic_arg
+{
+  tls_index tlsinfo;
+  size_t gen_count;
+};
+
+extern ptrdiff_t attribute_hidden _dl_tlsdesc_return (struct tlsdesc *);
+extern ptrdiff_t attribute_hidden _dl_tlsdesc_undefweak (struct tlsdesc *);
+
+#ifdef SHARED
+extern void *_dl_make_tlsdesc_dynamic (struct link_map *, size_t);
+extern ptrdiff_t attribute_hidden _dl_tlsdesc_dynamic (struct tlsdesc *);
+#endif
+
+#endif