gdb/riscv-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux on RISC-V processors.
   2    Copyright (C) 2018 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "defs.h"
  20 #include "riscv-tdep.h"
  21 #include "osabi.h"
  22 #include "glibc-tdep.h"
  23 #include "linux-tdep.h"
  24 #include "solib-svr4.h"
  25 #include "regset.h"
  26
  27 /* Define the general register mapping.  The kernel puts the PC at offset 0,
  28    gdb puts it at offset 32.  Register x0 is always 0 and can be ignored.
  29    Registers x1 to x31 are in the same place.  */
  30
  31 static const struct regcache_map_entry riscv_linux_gregmap[] =
  32 {
  33   { 1,  RISCV_PC_REGNUM, 0 },
  34   { 31, RISCV_RA_REGNUM, 0 }, /* x1 to x31 */
  35   { 0 }
  36 };
  37
  38 /* Define the general register regset.  */
  39
  40 static const struct regset riscv_linux_gregset =
  41 {
  42   riscv_linux_gregmap, regcache_supply_regset, regcache_collect_regset
  43 };
  44
  45 /* Define hook for core file support.  */
  46
  47 static void
  48 riscv_linux_iterate_over_regset_sections (struct gdbarch *gdbarch,
  49                                           iterate_over_regset_sections_cb *cb,
  50                                           void *cb_data,
  51                                           const struct regcache *regcache)
  52 {
  53   cb (".reg", (32 * riscv_isa_xlen (gdbarch)), (32 * riscv_isa_xlen (gdbarch)),
  54       &riscv_linux_gregset, NULL, cb_data);
  55
  56   /* TODO: Add FP register support.  */
  57 }
  58
  59 /* Initialize RISC-V Linux ABI info.  */
  60
  61 static void
  62 riscv_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  63 {
  64   linux_init_abi (info, gdbarch);
  65
  66   set_gdbarch_software_single_step (gdbarch, riscv_software_single_step);
  67
  68   set_solib_svr4_fetch_link_map_offsets (gdbarch,
  69                                          (riscv_isa_xlen (gdbarch) == 4
  70                                           ? svr4_ilp32_fetch_link_map_offsets
  71                                           : svr4_lp64_fetch_link_map_offsets));
  72
  73   /* GNU/Linux uses SVR4-style shared libraries.  */
  74   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
  75
  76   /* GNU/Linux uses the dynamic linker included in the GNU C Library.  */
  77   set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
  78
  79   /* Enable TLS support.  */
  80   set_gdbarch_fetch_tls_load_module_address (gdbarch,
  81                                              svr4_fetch_objfile_link_map);
  82
  83   set_gdbarch_iterate_over_regset_sections
  84     (gdbarch, riscv_linux_iterate_over_regset_sections);
  85 }
  86
  87 /* Initialize RISC-V Linux target support.  */
  88
  89 void
  90 _initialize_riscv_linux_tdep (void)
  91 {
  92   gdbarch_register_osabi (bfd_arch_riscv, 0, GDB_OSABI_LINUX,
  93                           riscv_linux_init_abi);
  94 }