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 protected:
  29
  30   void low_arch_setup () override;
  31 };
  32
  33 /* The singleton target ops object.  */
  34
  35 static sh_target the_sh_target;
  36
  37 /* Defined in auto-generated file reg-sh.c.  */
  38 void init_registers_sh (void);
  39 extern const struct target_desc *tdesc_sh;
  40
  41 #ifdef HAVE_SYS_REG_H
  42 #include <sys/reg.h>
  43 #endif
  44
  45 #include <asm/ptrace.h>
  46
  47 #define sh_num_regs 41
  48
  49 /* Currently, don't check/send MQ.  */
  50 static int sh_regmap[] = {
  51  0,     4,      8,      12,     16,     20,     24,     28,
  52  32,    36,     40,     44,     48,     52,     56,     60,
  53
  54  REG_PC*4,   REG_PR*4,   REG_GBR*4,  -1,
  55  REG_MACH*4, REG_MACL*4, REG_SR*4,
  56  REG_FPUL*4, REG_FPSCR*4,
  57
  58  REG_FPREG0*4+0,   REG_FPREG0*4+4,   REG_FPREG0*4+8,   REG_FPREG0*4+12,
  59  REG_FPREG0*4+16,  REG_FPREG0*4+20,  REG_FPREG0*4+24,  REG_FPREG0*4+28,
  60  REG_FPREG0*4+32,  REG_FPREG0*4+36,  REG_FPREG0*4+40,  REG_FPREG0*4+44,
  61  REG_FPREG0*4+48,  REG_FPREG0*4+52,  REG_FPREG0*4+56,  REG_FPREG0*4+60,
  62 };
  63
  64 static int
  65 sh_cannot_store_register (int regno)
  66 {
  67   return 0;
  68 }
  69
  70 static int
  71 sh_cannot_fetch_register (int regno)
  72 {
  73   return 0;
  74 }
  75
  76 /* Correct in either endianness, obviously.  */
  77 static const unsigned short sh_breakpoint = 0xc3c3;
  78 #define sh_breakpoint_len 2
  79
  80 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  81
  82 static const gdb_byte *
  83 sh_sw_breakpoint_from_kind (int kind, int *size)
  84 {
  85   *size = sh_breakpoint_len;
  86   return (const gdb_byte *) &sh_breakpoint;
  87 }
  88
  89 static int
  90 sh_breakpoint_at (CORE_ADDR where)
  91 {
  92   unsigned short insn;
  93
  94   the_target->read_memory (where, (unsigned char *) &insn, 2);
  95   if (insn == sh_breakpoint)
  96     return 1;
  97
  98   /* If necessary, recognize more trap instructions here.  GDB only uses the
  99      one.  */
 100   return 0;
 101 }
 102
 103 /* Support for hardware single step.  */
 104
 105 static int
 106 sh_supports_hardware_single_step (void)
 107 {
 108   return 1;
 109 }
 110
 111 /* Provide only a fill function for the general register set.  ps_lgetregs
 112    will use this for NPTL support.  */
 113
 114 static void sh_fill_gregset (struct regcache *regcache, void *buf)
 115 {
 116   int i;
 117
 118   for (i = 0; i < 23; i++)
 119     if (sh_regmap[i] != -1)
 120       collect_register (regcache, i, (char *) buf + sh_regmap[i]);
 121 }
 122
 123 static struct regset_info sh_regsets[] = {
 124   { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
 125   NULL_REGSET
 126 };
 127
 128 static struct regsets_info sh_regsets_info =
 129   {
 130     sh_regsets, /* regsets */
 131     0, /* num_regsets */
 132     NULL, /* disabled_regsets */
 133   };
 134
 135 static struct usrregs_info sh_usrregs_info =
 136   {
 137     sh_num_regs,
 138     sh_regmap,
 139   };
 140
 141 static struct regs_info regs_info =
 142   {
 143     NULL, /* regset_bitmap */
 144     &sh_usrregs_info,
 145     &sh_regsets_info
 146   };
 147
 148 static const struct regs_info *
 149 sh_regs_info (void)
 150 {
 151   return &regs_info;
 152 }
 153
 154 void
 155 sh_target::low_arch_setup ()
 156 {
 157   current_process ()->tdesc = tdesc_sh;
 158 }
 159
 160 struct linux_target_ops the_low_target = {
 161   sh_regs_info,
 162   sh_cannot_fetch_register,
 163   sh_cannot_store_register,
 164   NULL, /* fetch_register */
 165   linux_get_pc_32bit,
 166   linux_set_pc_32bit,
 167   NULL, /* breakpoint_kind_from_pc */
 168   sh_sw_breakpoint_from_kind,
 169   NULL,
 170   0,
 171   sh_breakpoint_at,
 172   NULL, /* supports_z_point_type */
 173   NULL, /* insert_point */
 174   NULL, /* remove_point */
 175   NULL, /* stopped_by_watchpoint */
 176   NULL, /* stopped_data_address */
 177   NULL, /* collect_ptrace_register */
 178   NULL, /* supply_ptrace_register */
 179   NULL, /* siginfo_fixup */
 180   NULL, /* new_process */
 181   NULL, /* delete_process */
 182   NULL, /* new_thread */
 183   NULL, /* delete_thread */
 184   NULL, /* new_fork */
 185   NULL, /* prepare_to_resume */
 186   NULL, /* process_qsupported */
 187   NULL, /* supports_tracepoints */
 188   NULL, /* get_thread_area */
 189   NULL, /* install_fast_tracepoint_jump_pad */
 190   NULL, /* emit_ops */
 191   NULL, /* get_min_fast_tracepoint_insn_len */
 192   NULL, /* supports_range_stepping */
 193   NULL, /* breakpoint_kind_from_current_state */
 194   sh_supports_hardware_single_step,
 195 };
 196
 197 /* The linux target ops object.  */
 198
 199 linux_process_target *the_linux_target = &the_sh_target;
 200
 201 void
 202 initialize_low_arch (void)
 203 {
 204   init_registers_sh ();
 205
 206   initialize_regsets_info (&sh_regsets_info);
 207 }