gdbserver/linux-tile-low.cc

   1 /* GNU/Linux/TILE-Gx specific low level interface, GDBserver.
   2
   3    Copyright (C) 2012-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "server.h"
  21 #include "linux-low.h"
  22
  23 #include <arch/abi.h>
  24 #include "nat/gdb_ptrace.h"
  25
  26 /* Linux target op definitions for the TILE-Gx architecture.  */
  27
  28 class tile_target : public linux_process_target
  29 {
  30 public:
  31
  32 };
  33
  34 /* The singleton target ops object.  */
  35
  36 static tile_target the_tile_target;
  37
  38 /* Defined in auto-generated file reg-tilegx.c.  */
  39 void init_registers_tilegx (void);
  40 extern const struct target_desc *tdesc_tilegx;
  41
  42 /* Defined in auto-generated file reg-tilegx32.c.  */
  43 void init_registers_tilegx32 (void);
  44 extern const struct target_desc *tdesc_tilegx32;
  45
  46 #define tile_num_regs 65
  47
  48 static int tile_regmap[] =
  49 {
  50    0,  1,  2,  3,  4,  5,  6,  7,
  51    8,  9, 10, 11, 12, 13, 14, 15,
  52   16, 17, 18, 19, 20, 21, 22, 23,
  53   24, 25, 26, 27, 28, 29, 30, 31,
  54   32, 33, 34, 35, 36, 37, 38, 39,
  55   40, 41, 42, 43, 44, 45, 46, 47,
  56   48, 49, 50, 51, 52, 53, 54, 55,
  57   -1, -1, -1, -1, -1, -1, -1, -1,
  58   56
  59 };
  60
  61 static int
  62 tile_cannot_fetch_register (int regno)
  63 {
  64   if (regno >= 0 && regno < 56)
  65     return 0;
  66   else if (regno == 64)
  67     return 0;
  68   else
  69     return 1;
  70 }
  71
  72 static int
  73 tile_cannot_store_register (int regno)
  74 {
  75   if (regno >= 0 && regno < 56)
  76     return 0;
  77   else if (regno == 64)
  78     return 0;
  79   else
  80     return 1;
  81 }
  82
  83 static uint64_t tile_breakpoint = 0x400b3cae70166000ULL;
  84 #define tile_breakpoint_len 8
  85
  86 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  87
  88 static const gdb_byte *
  89 tile_sw_breakpoint_from_kind (int kind, int *size)
  90 {
  91   *size = tile_breakpoint_len;
  92   return (const gdb_byte *) &tile_breakpoint;
  93 }
  94
  95 static int
  96 tile_breakpoint_at (CORE_ADDR where)
  97 {
  98   uint64_t insn;
  99
 100   the_target->read_memory (where, (unsigned char *) &insn, 8);
 101   if (insn == tile_breakpoint)
 102     return 1;
 103
 104   /* If necessary, recognize more trap instructions here.  GDB only uses the
 105      one.  */
 106   return 0;
 107 }
 108
 109 static void
 110 tile_fill_gregset (struct regcache *regcache, void *buf)
 111 {
 112   int i;
 113
 114   for (i = 0; i < tile_num_regs; i++)
 115     if (tile_regmap[i] != -1)
 116       collect_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 117 }
 118
 119 static void
 120 tile_store_gregset (struct regcache *regcache, const void *buf)
 121 {
 122   int i;
 123
 124   for (i = 0; i < tile_num_regs; i++)
 125     if (tile_regmap[i] != -1)
 126       supply_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 127 }
 128
 129 static struct regset_info tile_regsets[] =
 130 {
 131   { PTRACE_GETREGS, PTRACE_SETREGS, 0, tile_num_regs * 8,
 132     GENERAL_REGS, tile_fill_gregset, tile_store_gregset },
 133   NULL_REGSET
 134 };
 135
 136 static struct regsets_info tile_regsets_info =
 137   {
 138     tile_regsets, /* regsets */
 139     0, /* num_regsets */
 140     NULL, /* disabled_regsets */
 141   };
 142
 143 static struct usrregs_info tile_usrregs_info =
 144   {
 145     tile_num_regs,
 146     tile_regmap,
 147   };
 148
 149 static struct regs_info regs_info =
 150   {
 151     NULL, /* regset_bitmap */
 152     &tile_usrregs_info,
 153     &tile_regsets_info,
 154   };
 155
 156 static const struct regs_info *
 157 tile_regs_info (void)
 158 {
 159   return &regs_info;
 160 }
 161
 162 static void
 163 tile_arch_setup (void)
 164 {
 165   int pid = pid_of (current_thread);
 166   unsigned int machine;
 167   int is_elf64 = linux_pid_exe_is_elf_64_file (pid, &machine);
 168
 169   if (sizeof (void *) == 4)
 170     if (is_elf64 > 0)
 171       error (_("Can't debug 64-bit process with 32-bit GDBserver"));
 172
 173   if (!is_elf64)
 174     current_process ()->tdesc = tdesc_tilegx32;
 175   else
 176     current_process ()->tdesc = tdesc_tilegx;
 177 }
 178
 179 /* Support for hardware single step.  */
 180
 181 static int
 182 tile_supports_hardware_single_step (void)
 183 {
 184   return 1;
 185 }
 186
 187
 188 struct linux_target_ops the_low_target =
 189 {
 190   tile_arch_setup,
 191   tile_regs_info,
 192   tile_cannot_fetch_register,
 193   tile_cannot_store_register,
 194   NULL,
 195   linux_get_pc_64bit,
 196   linux_set_pc_64bit,
 197   NULL, /* breakpoint_kind_from_pc */
 198   tile_sw_breakpoint_from_kind,
 199   NULL,
 200   0,
 201   tile_breakpoint_at,
 202   NULL, /* supports_z_point_type */
 203   NULL, /* insert_point */
 204   NULL, /* remove_point */
 205   NULL, /* stopped_by_watchpoint */
 206   NULL, /* stopped_data_address */
 207   NULL, /* collect_ptrace_register */
 208   NULL, /* supply_ptrace_register */
 209   NULL, /* siginfo_fixup */
 210   NULL, /* new_process */
 211   NULL, /* delete_process */
 212   NULL, /* new_thread */
 213   NULL, /* delete_thread */
 214   NULL, /* new_fork */
 215   NULL, /* prepare_to_resume */
 216   NULL, /* process_qsupported */
 217   NULL, /* supports_tracepoints */
 218   NULL, /* get_thread_area */
 219   NULL, /* install_fast_tracepoint_jump_pad */
 220   NULL, /* emit_ops */
 221   NULL, /* get_min_fast_tracepoint_insn_len */
 222   NULL, /* supports_range_stepping */
 223   NULL, /* breakpoint_kind_from_current_state */
 224   tile_supports_hardware_single_step,
 225 };
 226
 227 /* The linux target ops object.  */
 228
 229 linux_process_target *the_linux_target = &the_tile_target;
 230
 231 void
 232 initialize_low_arch (void)
 233 {
 234   init_registers_tilegx32();
 235   init_registers_tilegx();
 236
 237   initialize_regsets_info (&tile_regsets_info);
 238 }