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