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 /* Defined in auto-generated file reg-sh.c.  */
  23 void init_registers_sh (void);
  24 extern const struct target_desc *tdesc_sh;
  25
  26 #ifdef HAVE_SYS_REG_H
  27 #include <sys/reg.h>
  28 #endif
  29
  30 #include <asm/ptrace.h>
  31
  32 #define sh_num_regs 41
  33
  34 /* Currently, don't check/send MQ.  */
  35 static int sh_regmap[] = {
  36  0,     4,      8,      12,     16,     20,     24,     28,
  37  32,    36,     40,     44,     48,     52,     56,     60,
  38
  39  REG_PC*4,   REG_PR*4,   REG_GBR*4,  -1,
  40  REG_MACH*4, REG_MACL*4, REG_SR*4,
  41  REG_FPUL*4, REG_FPSCR*4,
  42
  43  REG_FPREG0*4+0,   REG_FPREG0*4+4,   REG_FPREG0*4+8,   REG_FPREG0*4+12,
  44  REG_FPREG0*4+16,  REG_FPREG0*4+20,  REG_FPREG0*4+24,  REG_FPREG0*4+28,
  45  REG_FPREG0*4+32,  REG_FPREG0*4+36,  REG_FPREG0*4+40,  REG_FPREG0*4+44,
  46  REG_FPREG0*4+48,  REG_FPREG0*4+52,  REG_FPREG0*4+56,  REG_FPREG0*4+60,
  47 };
  48
  49 static int
  50 sh_cannot_store_register (int regno)
  51 {
  52   return 0;
  53 }
  54
  55 static int
  56 sh_cannot_fetch_register (int regno)
  57 {
  58   return 0;
  59 }
  60
  61 /* Correct in either endianness, obviously.  */
  62 static const unsigned short sh_breakpoint = 0xc3c3;
  63 #define sh_breakpoint_len 2
  64
  65 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  66
  67 static const gdb_byte *
  68 sh_sw_breakpoint_from_kind (int kind, int *size)
  69 {
  70   *size = sh_breakpoint_len;
  71   return (const gdb_byte *) &sh_breakpoint;
  72 }
  73
  74 static int
  75 sh_breakpoint_at (CORE_ADDR where)
  76 {
  77   unsigned short insn;
  78
  79   the_target->read_memory (where, (unsigned char *) &insn, 2);
  80   if (insn == sh_breakpoint)
  81     return 1;
  82
  83   /* If necessary, recognize more trap instructions here.  GDB only uses the
  84      one.  */
  85   return 0;
  86 }
  87
  88 /* Support for hardware single step.  */
  89
  90 static int
  91 sh_supports_hardware_single_step (void)
  92 {
  93   return 1;
  94 }
  95
  96 /* Provide only a fill function for the general register set.  ps_lgetregs
  97    will use this for NPTL support.  */
  98
  99 static void sh_fill_gregset (struct regcache *regcache, void *buf)
 100 {
 101   int i;
 102
 103   for (i = 0; i < 23; i++)
 104     if (sh_regmap[i] != -1)
 105       collect_register (regcache, i, (char *) buf + sh_regmap[i]);
 106 }
 107
 108 static struct regset_info sh_regsets[] = {
 109   { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
 110   NULL_REGSET
 111 };
 112
 113 static struct regsets_info sh_regsets_info =
 114   {
 115     sh_regsets, /* regsets */
 116     0, /* num_regsets */
 117     NULL, /* disabled_regsets */
 118   };
 119
 120 static struct usrregs_info sh_usrregs_info =
 121   {
 122     sh_num_regs,
 123     sh_regmap,
 124   };
 125
 126 static struct regs_info regs_info =
 127   {
 128     NULL, /* regset_bitmap */
 129     &sh_usrregs_info,
 130     &sh_regsets_info
 131   };
 132
 133 static const struct regs_info *
 134 sh_regs_info (void)
 135 {
 136   return &regs_info;
 137 }
 138
 139 static void
 140 sh_arch_setup (void)
 141 {
 142   current_process ()->tdesc = tdesc_sh;
 143 }
 144
 145 struct linux_target_ops the_low_target = {
 146   sh_arch_setup,
 147   sh_regs_info,
 148   sh_cannot_fetch_register,
 149   sh_cannot_store_register,
 150   NULL, /* fetch_register */
 151   linux_get_pc_32bit,
 152   linux_set_pc_32bit,
 153   NULL, /* breakpoint_kind_from_pc */
 154   sh_sw_breakpoint_from_kind,
 155   NULL,
 156   0,
 157   sh_breakpoint_at,
 158   NULL, /* supports_z_point_type */
 159   NULL, /* insert_point */
 160   NULL, /* remove_point */
 161   NULL, /* stopped_by_watchpoint */
 162   NULL, /* stopped_data_address */
 163   NULL, /* collect_ptrace_register */
 164   NULL, /* supply_ptrace_register */
 165   NULL, /* siginfo_fixup */
 166   NULL, /* new_process */
 167   NULL, /* delete_process */
 168   NULL, /* new_thread */
 169   NULL, /* delete_thread */
 170   NULL, /* new_fork */
 171   NULL, /* prepare_to_resume */
 172   NULL, /* process_qsupported */
 173   NULL, /* supports_tracepoints */
 174   NULL, /* get_thread_area */
 175   NULL, /* install_fast_tracepoint_jump_pad */
 176   NULL, /* emit_ops */
 177   NULL, /* get_min_fast_tracepoint_insn_len */
 178   NULL, /* supports_range_stepping */
 179   NULL, /* breakpoint_kind_from_current_state */
 180   sh_supports_hardware_single_step,
 181 };
 182
 183 void
 184 initialize_low_arch (void)
 185 {
 186   init_registers_sh ();
 187
 188   initialize_regsets_info (&sh_regsets_info);
 189 }