Line data    Source code

       1              : /* LoongArch ABI-specified defaults for DWARF CFI.
       2              :    Copyright (C) 2023 OpenAnolis community LoongArch SIG.
       3              :    Copyright (C) 2023 Loongson Technology Corporation Limted.
       4              :    This file is part of elfutils.
       5              : 
       6              :    This file is free software; you can redistribute it and/or modify
       7              :    it under the terms of either
       8              : 
       9              :      * the GNU Lesser General Public License as published by the Free
      10              :        Software Foundation; either version 3 of the License, or (at
      11              :        your option) any later version
      12              : 
      13              :    or
      14              : 
      15              :      * the GNU General Public License as published by the Free
      16              :        Software Foundation; either version 2 of the License, or (at
      17              :        your option) any later version
      18              : 
      19              :    or both in parallel, as here.
      20              : 
      21              :    elfutils is distributed in the hope that it will be useful, but
      22              :    WITHOUT ANY WARRANTY; without even the implied warranty of
      23              :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      24              :    General Public License for more details.
      25              : 
      26              :    You should have received copies of the GNU General Public License and
      27              :    the GNU Lesser General Public License along with this program.  If
      28              :    not, see <http://www.gnu.org/licenses/>.  */
      29              : 
      30              : #ifdef HAVE_CONFIG_H
      31              : # include <config.h>
      32              : #endif
      33              : 
      34              : #include <dwarf.h>
      35              : 
      36              : #define BACKEND loongarch_
      37              : #include "libebl_CPU.h"
      38              : 
      39              : /* LoongArch ELF ABI specification:
      40              : https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html#_register_convention
      41              : */
      42              : int
      43            0 : loongarch_abi_cfi (Ebl *ebl __attribute__ ((unused)), Dwarf_CIE *abi_info)
      44              : {
      45            0 :   static const uint8_t abi_cfi[] =
      46              :     {
      47              :       /* The initial Canonical Frame Address is the value of the
      48              :          Stack Pointer ($r3) as setup in the previous frame. */
      49              :       DW_CFA_def_cfa, ULEB128_7 (3), ULEB128_7 (0),
      50              : 
      51              :       /* The Stack Pointer ($r3) is restored from CFA address by default.  */
      52              :       DW_CFA_val_offset, ULEB128_7 (3), ULEB128_7 (0),
      53              : 
      54              : #define SV(n) DW_CFA_same_value, ULEB128_7 (n)
      55              :       /* The return address register contains the return address setup by
      56              :          caller.  */
      57              :       SV (1),
      58              : 
      59              :       /* Callee-saved registers $s0-$s7.  */
      60              :       SV (23), SV (24), SV (25), SV (26), SV (27), SV (28),
      61              :       SV (29), SV (30), SV (31),
      62              : 
      63              :       /* The Frame Pointer ($fp, $r22) */
      64              :       SV(22),
      65              : 
      66              :       /* Callee-saved registers $fs0-$fs7.  */
      67              :       SV (56), SV (57), SV (58), SV (59), SV (60), SV (61),
      68              :       SV (62), SV (63),
      69              : #undef SV
      70              : 
      71              :       /* XXX Note: registers intentionally unused by the program,
      72              :          for example as a consequence of the procedure call standard
      73              :          should be initialized as if by DW_CFA_same_value.  */
      74              :     };
      75              : 
      76            0 :   abi_info->initial_instructions = abi_cfi;
      77            0 :   abi_info->initial_instructions_end = &abi_cfi[sizeof abi_cfi];
      78            0 :   abi_info->data_alignment_factor = -4;
      79              : 
      80            0 :   abi_info->return_address_register = 1; /* ra.  */
      81              : 
      82            0 :   return 0;
      83              : }