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   const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
  35
  36 protected:
  37
  38   void low_arch_setup () override;
  39
  40   bool low_cannot_fetch_register (int regno) override;
  41
  42   bool low_cannot_store_register (int regno) override;
  43
  44   bool low_supports_breakpoints () override;
  45
  46   CORE_ADDR low_get_pc (regcache *regcache) override;
  47
  48   void low_set_pc (regcache *regcache, CORE_ADDR newpc) override;
  49 };
  50
  51 /* The singleton target ops object.  */
  52
  53 static tile_target the_tile_target;
  54
  55 bool
  56 tile_target::low_supports_breakpoints ()
  57 {
  58   return true;
  59 }
  60
  61 CORE_ADDR
  62 tile_target::low_get_pc (regcache *regcache)
  63 {
  64   return linux_get_pc_64bit (regcache);
  65 }
  66
  67 void
  68 tile_target::low_set_pc (regcache *regcache, CORE_ADDR pc)
  69 {
  70   linux_set_pc_64bit (regcache, pc);
  71 }
  72
  73 /* Defined in auto-generated file reg-tilegx.c.  */
  74 void init_registers_tilegx (void);
  75 extern const struct target_desc *tdesc_tilegx;
  76
  77 /* Defined in auto-generated file reg-tilegx32.c.  */
  78 void init_registers_tilegx32 (void);
  79 extern const struct target_desc *tdesc_tilegx32;
  80
  81 #define tile_num_regs 65
  82
  83 static int tile_regmap[] =
  84 {
  85    0,  1,  2,  3,  4,  5,  6,  7,
  86    8,  9, 10, 11, 12, 13, 14, 15,
  87   16, 17, 18, 19, 20, 21, 22, 23,
  88   24, 25, 26, 27, 28, 29, 30, 31,
  89   32, 33, 34, 35, 36, 37, 38, 39,
  90   40, 41, 42, 43, 44, 45, 46, 47,
  91   48, 49, 50, 51, 52, 53, 54, 55,
  92   -1, -1, -1, -1, -1, -1, -1, -1,
  93   56
  94 };
  95
  96 bool
  97 tile_target::low_cannot_fetch_register (int regno)
  98 {
  99   if (regno >= 0 && regno < 56)
 100     return false;
 101   else if (regno == 64)
 102     return false;
 103   else
 104     return true;
 105 }
 106
 107 bool
 108 tile_target::low_cannot_store_register (int regno)
 109 {
 110   if (regno >= 0 && regno < 56)
 111     return false;
 112   else if (regno == 64)
 113     return false;
 114   else
 115     return true;
 116 }
 117
 118 static uint64_t tile_breakpoint = 0x400b3cae70166000ULL;
 119 #define tile_breakpoint_len 8
 120
 121 /* Implementation of target ops method "sw_breakpoint_from_kind".  */
 122
 123 const gdb_byte *
 124 tile_target::sw_breakpoint_from_kind (int kind, int *size)
 125 {
 126   *size = tile_breakpoint_len;
 127   return (const gdb_byte *) &tile_breakpoint;
 128 }
 129
 130 static int
 131 tile_breakpoint_at (CORE_ADDR where)
 132 {
 133   uint64_t insn;
 134
 135   the_target->read_memory (where, (unsigned char *) &insn, 8);
 136   if (insn == tile_breakpoint)
 137     return 1;
 138
 139   /* If necessary, recognize more trap instructions here.  GDB only uses the
 140      one.  */
 141   return 0;
 142 }
 143
 144 static void
 145 tile_fill_gregset (struct regcache *regcache, void *buf)
 146 {
 147   int i;
 148
 149   for (i = 0; i < tile_num_regs; i++)
 150     if (tile_regmap[i] != -1)
 151       collect_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 152 }
 153
 154 static void
 155 tile_store_gregset (struct regcache *regcache, const void *buf)
 156 {
 157   int i;
 158
 159   for (i = 0; i < tile_num_regs; i++)
 160     if (tile_regmap[i] != -1)
 161       supply_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 162 }
 163
 164 static struct regset_info tile_regsets[] =
 165 {
 166   { PTRACE_GETREGS, PTRACE_SETREGS, 0, tile_num_regs * 8,
 167     GENERAL_REGS, tile_fill_gregset, tile_store_gregset },
 168   NULL_REGSET
 169 };
 170
 171 static struct regsets_info tile_regsets_info =
 172   {
 173     tile_regsets, /* regsets */
 174     0, /* num_regsets */
 175     NULL, /* disabled_regsets */
 176   };
 177
 178 static struct usrregs_info tile_usrregs_info =
 179   {
 180     tile_num_regs,
 181     tile_regmap,
 182   };
 183
 184 static struct regs_info myregs_info =
 185   {
 186     NULL, /* regset_bitmap */
 187     &tile_usrregs_info,
 188     &tile_regsets_info,
 189   };
 190
 191 const regs_info *
 192 tile_target::get_regs_info ()
 193 {
 194   return &myregs_info;
 195 }
 196
 197 void
 198 tile_target::low_arch_setup ()
 199 {
 200   int pid = pid_of (current_thread);
 201   unsigned int machine;
 202   int is_elf64 = linux_pid_exe_is_elf_64_file (pid, &machine);
 203
 204   if (sizeof (void *) == 4)
 205     if (is_elf64 > 0)
 206       error (_("Can't debug 64-bit process with 32-bit GDBserver"));
 207
 208   if (!is_elf64)
 209     current_process ()->tdesc = tdesc_tilegx32;
 210   else
 211     current_process ()->tdesc = tdesc_tilegx;
 212 }
 213
 214 /* Support for hardware single step.  */
 215
 216 static int
 217 tile_supports_hardware_single_step (void)
 218 {
 219   return 1;
 220 }
 221
 222
 223 struct linux_target_ops the_low_target =
 224 {
 225   NULL,
 226   0,
 227   tile_breakpoint_at,
 228   NULL, /* supports_z_point_type */
 229   NULL, /* insert_point */
 230   NULL, /* remove_point */
 231   NULL, /* stopped_by_watchpoint */
 232   NULL, /* stopped_data_address */
 233   NULL, /* collect_ptrace_register */
 234   NULL, /* supply_ptrace_register */
 235   NULL, /* siginfo_fixup */
 236   NULL, /* new_process */
 237   NULL, /* delete_process */
 238   NULL, /* new_thread */
 239   NULL, /* delete_thread */
 240   NULL, /* new_fork */
 241   NULL, /* prepare_to_resume */
 242   NULL, /* process_qsupported */
 243   NULL, /* supports_tracepoints */
 244   NULL, /* get_thread_area */
 245   NULL, /* install_fast_tracepoint_jump_pad */
 246   NULL, /* emit_ops */
 247   NULL, /* get_min_fast_tracepoint_insn_len */
 248   NULL, /* supports_range_stepping */
 249   tile_supports_hardware_single_step,
 250 };
 251
 252 /* The linux target ops object.  */
 253
 254 linux_process_target *the_linux_target = &the_tile_target;
 255
 256 void
 257 initialize_low_arch (void)
 258 {
 259   init_registers_tilegx32();
 260   init_registers_tilegx();
 261
 262   initialize_regsets_info (&tile_regsets_info);
 263 }