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