Add backend support for C-SKY

C-SKY V2 ABI manual:
https://github.com/c-sky/csky-doc/blob/master/C-SKY_V2_CPU_Applications_Binary_Interface_Standards_Manual.pdf
C-SKY architecture user guide:
https://github.com/c-sky/csky-doc/blob/master/CSKY%20Architecture%20user_guide.pdf

Signed-off-by: Mao Han <han_mao@c-sky.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/backends/csky_cfi.c b/backends/csky_cfi.c
new file mode 100644
index 00000000..7277dbd4
--- /dev/null
+++ b/backends/csky_cfi.c
@@ -0,0 +1,60 @@
+/* C-SKY ABI-specified defaults for DWARF CFI.
+   Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <dwarf.h>
+
+#define BACKEND csky_
+#include "libebl_CPU.h"
+
+
+int
+csky_abi_cfi (Ebl *ebl __attribute__ ((unused)), Dwarf_CIE *abi_info)
+{
+  static const uint8_t abi_cfi[] =
+    {
+      DW_CFA_def_cfa, ULEB128_7 (14), ULEB128_7 (0),
+      DW_CFA_val_offset, ULEB128_7 (14), ULEB128_7 (0),
+
+#define SV(n) DW_CFA_same_value, ULEB128_7 (n)
+      SV(4), SV (5), SV (6), SV (7), SV (8), SV (9),
+      SV(10), SV (11), SV (15), SV (16), SV (17)
+#undef SV
+    };
+
+  abi_info->initial_instructions = abi_cfi;
+  abi_info->initial_instructions_end = &abi_cfi[sizeof abi_cfi];
+  abi_info->data_alignment_factor = -4;
+
+  abi_info->return_address_register = 15; /* lr.  */
+
+  return 0;
+}