gdbserver/linux-sh-low.cc

   1 /* GNU/Linux/SH specific low level interface, for the remote server for GDB.
   2    Copyright (C) 1995-2020 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "server.h"
  20 #include "linux-low.h"
  21
  22 /* Linux target op definitions for the SH architecture.  */
  23
  24 class sh_target : public linux_process_target
  25 {
  26 public:
  27
  28   const regs_info *get_regs_info () override;
  29
  30 protected:
  31
  32   void low_arch_setup () override;
  33 };
  34
  35 /* The singleton target ops object.  */
  36
  37 static sh_target the_sh_target;
  38
  39 /* Defined in auto-generated file reg-sh.c.  */
  40 void init_registers_sh (void);
  41 extern const struct target_desc *tdesc_sh;
  42
  43 #ifdef HAVE_SYS_REG_H
  44 #include <sys/reg.h>
  45 #endif
  46
  47 #include <asm/ptrace.h>
  48
  49 #define sh_num_regs 41
  50
  51 /* Currently, don't check/send MQ.  */
  52 static int sh_regmap[] = {
  53  0,     4,      8,      12,     16,     20,     24,     28,
  54  32,    36,     40,     44,     48,     52,     56,     60,
  55
  56  REG_PC*4,   REG_PR*4,   REG_GBR*4,  -1,
  57  REG_MACH*4, REG_MACL*4, REG_SR*4,
  58  REG_FPUL*4, REG_FPSCR*4,
  59
  60  REG_FPREG0*4+0,   REG_FPREG0*4+4,   REG_FPREG0*4+8,   REG_FPREG0*4+12,
  61  REG_FPREG0*4+16,  REG_FPREG0*4+20,  REG_FPREG0*4+24,  REG_FPREG0*4+28,
  62  REG_FPREG0*4+32,  REG_FPREG0*4+36,  REG_FPREG0*4+40,  REG_FPREG0*4+44,
  63  REG_FPREG0*4+48,  REG_FPREG0*4+52,  REG_FPREG0*4+56,  REG_FPREG0*4+60,
  64 };
  65
  66 static int
  67 sh_cannot_store_register (int regno)
  68 {
  69   return 0;
  70 }
  71
  72 static int
  73 sh_cannot_fetch_register (int regno)
  74 {
  75   return 0;
  76 }
  77
  78 /* Correct in either endianness, obviously.  */
  79 static const unsigned short sh_breakpoint = 0xc3c3;
  80 #define sh_breakpoint_len 2
  81
  82 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  83
  84 static const gdb_byte *
  85 sh_sw_breakpoint_from_kind (int kind, int *size)
  86 {
  87   *size = sh_breakpoint_len;
  88   return (const gdb_byte *) &sh_breakpoint;
  89 }
  90
  91 static int
  92 sh_breakpoint_at (CORE_ADDR where)
  93 {
  94   unsigned short insn;
  95
  96   the_target->read_memory (where, (unsigned char *) &insn, 2);
  97   if (insn == sh_breakpoint)
  98     return 1;
  99
 100   /* If necessary, recognize more trap instructions here.  GDB only uses the
 101      one.  */
 102   return 0;
 103 }
 104
 105 /* Support for hardware single step.  */
 106
 107 static int
 108 sh_supports_hardware_single_step (void)
 109 {
 110   return 1;
 111 }
 112
 113 /* Provide only a fill function for the general register set.  ps_lgetregs
 114    will use this for NPTL support.  */
 115
 116 static void sh_fill_gregset (struct regcache *regcache, void *buf)
 117 {
 118   int i;
 119
 120   for (i = 0; i < 23; i++)
 121     if (sh_regmap[i] != -1)
 122       collect_register (regcache, i, (char *) buf + sh_regmap[i]);
 123 }
 124
 125 static struct regset_info sh_regsets[] = {
 126   { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
 127   NULL_REGSET
 128 };
 129
 130 static struct regsets_info sh_regsets_info =
 131   {
 132     sh_regsets, /* regsets */
 133     0, /* num_regsets */
 134     NULL, /* disabled_regsets */
 135   };
 136
 137 static struct usrregs_info sh_usrregs_info =
 138   {
 139     sh_num_regs,
 140     sh_regmap,
 141   };
 142
 143 static struct regs_info myregs_info =
 144   {
 145     NULL, /* regset_bitmap */
 146     &sh_usrregs_info,
 147     &sh_regsets_info
 148   };
 149
 150 const regs_info *
 151 sh_target::get_regs_info ()
 152 {
 153   return &myregs_info;
 154 }
 155
 156 void
 157 sh_target::low_arch_setup ()
 158 {
 159   current_process ()->tdesc = tdesc_sh;
 160 }
 161
 162 struct linux_target_ops the_low_target = {
 163   sh_cannot_fetch_register,
 164   sh_cannot_store_register,
 165   NULL, /* fetch_register */
 166   linux_get_pc_32bit,
 167   linux_set_pc_32bit,
 168   NULL, /* breakpoint_kind_from_pc */
 169   sh_sw_breakpoint_from_kind,
 170   NULL,
 171   0,
 172   sh_breakpoint_at,
 173   NULL, /* supports_z_point_type */
 174   NULL, /* insert_point */
 175   NULL, /* remove_point */
 176   NULL, /* stopped_by_watchpoint */
 177   NULL, /* stopped_data_address */
 178   NULL, /* collect_ptrace_register */
 179   NULL, /* supply_ptrace_register */
 180   NULL, /* siginfo_fixup */
 181   NULL, /* new_process */
 182   NULL, /* delete_process */
 183   NULL, /* new_thread */
 184   NULL, /* delete_thread */
 185   NULL, /* new_fork */
 186   NULL, /* prepare_to_resume */
 187   NULL, /* process_qsupported */
 188   NULL, /* supports_tracepoints */
 189   NULL, /* get_thread_area */
 190   NULL, /* install_fast_tracepoint_jump_pad */
 191   NULL, /* emit_ops */
 192   NULL, /* get_min_fast_tracepoint_insn_len */
 193   NULL, /* supports_range_stepping */
 194   NULL, /* breakpoint_kind_from_current_state */
 195   sh_supports_hardware_single_step,
 196 };
 197
 198 /* The linux target ops object.  */
 199
 200 linux_process_target *the_linux_target = &the_sh_target;
 201
 202 void
 203 initialize_low_arch (void)
 204 {
 205   init_registers_sh ();
 206
 207   initialize_regsets_info (&sh_regsets_info);
 208 }