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