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   const regs_info *get_regs_info () override;
  33
  34 protected:
  35
  36   void low_arch_setup () override;
  37
  38   bool low_cannot_fetch_register (int regno) override;
  39
  40   bool low_cannot_store_register (int regno) override;
  41 };
  42
  43 /* The singleton target ops object.  */
  44
  45 static tile_target the_tile_target;
  46
  47 /* Defined in auto-generated file reg-tilegx.c.  */
  48 void init_registers_tilegx (void);
  49 extern const struct target_desc *tdesc_tilegx;
  50
  51 /* Defined in auto-generated file reg-tilegx32.c.  */
  52 void init_registers_tilegx32 (void);
  53 extern const struct target_desc *tdesc_tilegx32;
  54
  55 #define tile_num_regs 65
  56
  57 static int tile_regmap[] =
  58 {
  59    0,  1,  2,  3,  4,  5,  6,  7,
  60    8,  9, 10, 11, 12, 13, 14, 15,
  61   16, 17, 18, 19, 20, 21, 22, 23,
  62   24, 25, 26, 27, 28, 29, 30, 31,
  63   32, 33, 34, 35, 36, 37, 38, 39,
  64   40, 41, 42, 43, 44, 45, 46, 47,
  65   48, 49, 50, 51, 52, 53, 54, 55,
  66   -1, -1, -1, -1, -1, -1, -1, -1,
  67   56
  68 };
  69
  70 bool
  71 tile_target::low_cannot_fetch_register (int regno)
  72 {
  73   if (regno >= 0 && regno < 56)
  74     return false;
  75   else if (regno == 64)
  76     return false;
  77   else
  78     return true;
  79 }
  80
  81 bool
  82 tile_target::low_cannot_store_register (int regno)
  83 {
  84   if (regno >= 0 && regno < 56)
  85     return false;
  86   else if (regno == 64)
  87     return false;
  88   else
  89     return true;
  90 }
  91
  92 static uint64_t tile_breakpoint = 0x400b3cae70166000ULL;
  93 #define tile_breakpoint_len 8
  94
  95 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  96
  97 static const gdb_byte *
  98 tile_sw_breakpoint_from_kind (int kind, int *size)
  99 {
 100   *size = tile_breakpoint_len;
 101   return (const gdb_byte *) &tile_breakpoint;
 102 }
 103
 104 static int
 105 tile_breakpoint_at (CORE_ADDR where)
 106 {
 107   uint64_t insn;
 108
 109   the_target->read_memory (where, (unsigned char *) &insn, 8);
 110   if (insn == tile_breakpoint)
 111     return 1;
 112
 113   /* If necessary, recognize more trap instructions here.  GDB only uses the
 114      one.  */
 115   return 0;
 116 }
 117
 118 static void
 119 tile_fill_gregset (struct regcache *regcache, void *buf)
 120 {
 121   int i;
 122
 123   for (i = 0; i < tile_num_regs; i++)
 124     if (tile_regmap[i] != -1)
 125       collect_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 126 }
 127
 128 static void
 129 tile_store_gregset (struct regcache *regcache, const void *buf)
 130 {
 131   int i;
 132
 133   for (i = 0; i < tile_num_regs; i++)
 134     if (tile_regmap[i] != -1)
 135       supply_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 136 }
 137
 138 static struct regset_info tile_regsets[] =
 139 {
 140   { PTRACE_GETREGS, PTRACE_SETREGS, 0, tile_num_regs * 8,
 141     GENERAL_REGS, tile_fill_gregset, tile_store_gregset },
 142   NULL_REGSET
 143 };
 144
 145 static struct regsets_info tile_regsets_info =
 146   {
 147     tile_regsets, /* regsets */
 148     0, /* num_regsets */
 149     NULL, /* disabled_regsets */
 150   };
 151
 152 static struct usrregs_info tile_usrregs_info =
 153   {
 154     tile_num_regs,
 155     tile_regmap,
 156   };
 157
 158 static struct regs_info myregs_info =
 159   {
 160     NULL, /* regset_bitmap */
 161     &tile_usrregs_info,
 162     &tile_regsets_info,
 163   };
 164
 165 const regs_info *
 166 tile_target::get_regs_info ()
 167 {
 168   return &myregs_info;
 169 }
 170
 171 void
 172 tile_target::low_arch_setup ()
 173 {
 174   int pid = pid_of (current_thread);
 175   unsigned int machine;
 176   int is_elf64 = linux_pid_exe_is_elf_64_file (pid, &machine);
 177
 178   if (sizeof (void *) == 4)
 179     if (is_elf64 > 0)
 180       error (_("Can't debug 64-bit process with 32-bit GDBserver"));
 181
 182   if (!is_elf64)
 183     current_process ()->tdesc = tdesc_tilegx32;
 184   else
 185     current_process ()->tdesc = tdesc_tilegx;
 186 }
 187
 188 /* Support for hardware single step.  */
 189
 190 static int
 191 tile_supports_hardware_single_step (void)
 192 {
 193   return 1;
 194 }
 195
 196
 197 struct linux_target_ops the_low_target =
 198 {
 199   linux_get_pc_64bit,
 200   linux_set_pc_64bit,
 201   NULL, /* breakpoint_kind_from_pc */
 202   tile_sw_breakpoint_from_kind,
 203   NULL,
 204   0,
 205   tile_breakpoint_at,
 206   NULL, /* supports_z_point_type */
 207   NULL, /* insert_point */
 208   NULL, /* remove_point */
 209   NULL, /* stopped_by_watchpoint */
 210   NULL, /* stopped_data_address */
 211   NULL, /* collect_ptrace_register */
 212   NULL, /* supply_ptrace_register */
 213   NULL, /* siginfo_fixup */
 214   NULL, /* new_process */
 215   NULL, /* delete_process */
 216   NULL, /* new_thread */
 217   NULL, /* delete_thread */
 218   NULL, /* new_fork */
 219   NULL, /* prepare_to_resume */
 220   NULL, /* process_qsupported */
 221   NULL, /* supports_tracepoints */
 222   NULL, /* get_thread_area */
 223   NULL, /* install_fast_tracepoint_jump_pad */
 224   NULL, /* emit_ops */
 225   NULL, /* get_min_fast_tracepoint_insn_len */
 226   NULL, /* supports_range_stepping */
 227   NULL, /* breakpoint_kind_from_current_state */
 228   tile_supports_hardware_single_step,
 229 };
 230
 231 /* The linux target ops object.  */
 232
 233 linux_process_target *the_linux_target = &the_tile_target;
 234
 235 void
 236 initialize_low_arch (void)
 237 {
 238   init_registers_tilegx32();
 239   init_registers_tilegx();
 240
 241   initialize_regsets_info (&tile_regsets_info);
 242 }