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   bool low_cannot_fetch_register (int regno) override;
  35
  36   bool low_cannot_store_register (int regno) override;
  37 };
  38
  39 /* The singleton target ops object.  */
  40
  41 static sh_target the_sh_target;
  42
  43 /* Defined in auto-generated file reg-sh.c.  */
  44 void init_registers_sh (void);
  45 extern const struct target_desc *tdesc_sh;
  46
  47 #ifdef HAVE_SYS_REG_H
  48 #include <sys/reg.h>
  49 #endif
  50
  51 #include <asm/ptrace.h>
  52
  53 #define sh_num_regs 41
  54
  55 /* Currently, don't check/send MQ.  */
  56 static int sh_regmap[] = {
  57  0,     4,      8,      12,     16,     20,     24,     28,
  58  32,    36,     40,     44,     48,     52,     56,     60,
  59
  60  REG_PC*4,   REG_PR*4,   REG_GBR*4,  -1,
  61  REG_MACH*4, REG_MACL*4, REG_SR*4,
  62  REG_FPUL*4, REG_FPSCR*4,
  63
  64  REG_FPREG0*4+0,   REG_FPREG0*4+4,   REG_FPREG0*4+8,   REG_FPREG0*4+12,
  65  REG_FPREG0*4+16,  REG_FPREG0*4+20,  REG_FPREG0*4+24,  REG_FPREG0*4+28,
  66  REG_FPREG0*4+32,  REG_FPREG0*4+36,  REG_FPREG0*4+40,  REG_FPREG0*4+44,
  67  REG_FPREG0*4+48,  REG_FPREG0*4+52,  REG_FPREG0*4+56,  REG_FPREG0*4+60,
  68 };
  69
  70 bool
  71 sh_target::low_cannot_store_register (int regno)
  72 {
  73   return false;
  74 }
  75
  76 bool
  77 sh_target::low_cannot_fetch_register (int regno)
  78 {
  79   return false;
  80 }
  81
  82 /* Correct in either endianness, obviously.  */
  83 static const unsigned short sh_breakpoint = 0xc3c3;
  84 #define sh_breakpoint_len 2
  85
  86 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  87
  88 static const gdb_byte *
  89 sh_sw_breakpoint_from_kind (int kind, int *size)
  90 {
  91   *size = sh_breakpoint_len;
  92   return (const gdb_byte *) &sh_breakpoint;
  93 }
  94
  95 static int
  96 sh_breakpoint_at (CORE_ADDR where)
  97 {
  98   unsigned short insn;
  99
 100   the_target->read_memory (where, (unsigned char *) &insn, 2);
 101   if (insn == sh_breakpoint)
 102     return 1;
 103
 104   /* If necessary, recognize more trap instructions here.  GDB only uses the
 105      one.  */
 106   return 0;
 107 }
 108
 109 /* Support for hardware single step.  */
 110
 111 static int
 112 sh_supports_hardware_single_step (void)
 113 {
 114   return 1;
 115 }
 116
 117 /* Provide only a fill function for the general register set.  ps_lgetregs
 118    will use this for NPTL support.  */
 119
 120 static void sh_fill_gregset (struct regcache *regcache, void *buf)
 121 {
 122   int i;
 123
 124   for (i = 0; i < 23; i++)
 125     if (sh_regmap[i] != -1)
 126       collect_register (regcache, i, (char *) buf + sh_regmap[i]);
 127 }
 128
 129 static struct regset_info sh_regsets[] = {
 130   { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
 131   NULL_REGSET
 132 };
 133
 134 static struct regsets_info sh_regsets_info =
 135   {
 136     sh_regsets, /* regsets */
 137     0, /* num_regsets */
 138     NULL, /* disabled_regsets */
 139   };
 140
 141 static struct usrregs_info sh_usrregs_info =
 142   {
 143     sh_num_regs,
 144     sh_regmap,
 145   };
 146
 147 static struct regs_info myregs_info =
 148   {
 149     NULL, /* regset_bitmap */
 150     &sh_usrregs_info,
 151     &sh_regsets_info
 152   };
 153
 154 const regs_info *
 155 sh_target::get_regs_info ()
 156 {
 157   return &myregs_info;
 158 }
 159
 160 void
 161 sh_target::low_arch_setup ()
 162 {
 163   current_process ()->tdesc = tdesc_sh;
 164 }
 165
 166 struct linux_target_ops the_low_target = {
 167   linux_get_pc_32bit,
 168   linux_set_pc_32bit,
 169   NULL, /* breakpoint_kind_from_pc */
 170   sh_sw_breakpoint_from_kind,
 171   NULL,
 172   0,
 173   sh_breakpoint_at,
 174   NULL, /* supports_z_point_type */
 175   NULL, /* insert_point */
 176   NULL, /* remove_point */
 177   NULL, /* stopped_by_watchpoint */
 178   NULL, /* stopped_data_address */
 179   NULL, /* collect_ptrace_register */
 180   NULL, /* supply_ptrace_register */
 181   NULL, /* siginfo_fixup */
 182   NULL, /* new_process */
 183   NULL, /* delete_process */
 184   NULL, /* new_thread */
 185   NULL, /* delete_thread */
 186   NULL, /* new_fork */
 187   NULL, /* prepare_to_resume */
 188   NULL, /* process_qsupported */
 189   NULL, /* supports_tracepoints */
 190   NULL, /* get_thread_area */
 191   NULL, /* install_fast_tracepoint_jump_pad */
 192   NULL, /* emit_ops */
 193   NULL, /* get_min_fast_tracepoint_insn_len */
 194   NULL, /* supports_range_stepping */
 195   NULL, /* breakpoint_kind_from_current_state */
 196   sh_supports_hardware_single_step,
 197 };
 198
 199 /* The linux target ops object.  */
 200
 201 linux_process_target *the_linux_target = &the_sh_target;
 202
 203 void
 204 initialize_low_arch (void)
 205 {
 206   init_registers_sh ();
 207
 208   initialize_regsets_info (&sh_regsets_info);
 209 }