Fix: A potential null_pointer_deference bug
[binutils-gdb.git] / gdbserver / linux-sh-low.cc
blob782b82920102a84cc4ab969fa6217b1c87b3cb91
1 /* GNU/Linux/SH specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2023 Free Software Foundation, Inc.
4 This file is part of GDB.
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.
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.
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/>. */
19 #include "server.h"
20 #include "linux-low.h"
22 /* Linux target op definitions for the SH architecture. */
24 class sh_target : public linux_process_target
26 public:
28 const regs_info *get_regs_info () override;
30 const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
32 protected:
34 void low_arch_setup () override;
36 bool low_cannot_fetch_register (int regno) override;
38 bool low_cannot_store_register (int regno) override;
40 bool low_supports_breakpoints () override;
42 CORE_ADDR low_get_pc (regcache *regcache) override;
44 void low_set_pc (regcache *regcache, CORE_ADDR newpc) override;
46 bool low_breakpoint_at (CORE_ADDR pc) override;
49 /* The singleton target ops object. */
51 static sh_target the_sh_target;
53 bool
54 sh_target::low_supports_breakpoints ()
56 return true;
59 CORE_ADDR
60 sh_target::low_get_pc (regcache *regcache)
62 return linux_get_pc_32bit (regcache);
65 void
66 sh_target::low_set_pc (regcache *regcache, CORE_ADDR pc)
68 linux_set_pc_32bit (regcache, pc);
71 /* Defined in auto-generated file reg-sh.c. */
72 void init_registers_sh (void);
73 extern const struct target_desc *tdesc_sh;
75 #ifdef HAVE_SYS_REG_H
76 #include <sys/reg.h>
77 #endif
79 #include <asm/ptrace.h>
81 #define sh_num_regs 41
83 /* Currently, don't check/send MQ. */
84 static int sh_regmap[] = {
85 0, 4, 8, 12, 16, 20, 24, 28,
86 32, 36, 40, 44, 48, 52, 56, 60,
88 REG_PC*4, REG_PR*4, REG_GBR*4, -1,
89 REG_MACH*4, REG_MACL*4, REG_SR*4,
90 REG_FPUL*4, REG_FPSCR*4,
92 REG_FPREG0*4+0, REG_FPREG0*4+4, REG_FPREG0*4+8, REG_FPREG0*4+12,
93 REG_FPREG0*4+16, REG_FPREG0*4+20, REG_FPREG0*4+24, REG_FPREG0*4+28,
94 REG_FPREG0*4+32, REG_FPREG0*4+36, REG_FPREG0*4+40, REG_FPREG0*4+44,
95 REG_FPREG0*4+48, REG_FPREG0*4+52, REG_FPREG0*4+56, REG_FPREG0*4+60,
98 bool
99 sh_target::low_cannot_store_register (int regno)
101 return false;
104 bool
105 sh_target::low_cannot_fetch_register (int regno)
107 return false;
110 /* Correct in either endianness, obviously. */
111 static const unsigned short sh_breakpoint = 0xc3c3;
112 #define sh_breakpoint_len 2
114 /* Implementation of target ops method "sw_breakpoint_from_kind". */
116 const gdb_byte *
117 sh_target::sw_breakpoint_from_kind (int kind, int *size)
119 *size = sh_breakpoint_len;
120 return (const gdb_byte *) &sh_breakpoint;
123 bool
124 sh_target::low_breakpoint_at (CORE_ADDR where)
126 unsigned short insn;
128 read_memory (where, (unsigned char *) &insn, 2);
129 if (insn == sh_breakpoint)
130 return true;
132 /* If necessary, recognize more trap instructions here. GDB only uses the
133 one. */
134 return false;
137 /* Provide only a fill function for the general register set. ps_lgetregs
138 will use this for NPTL support. */
140 static void sh_fill_gregset (struct regcache *regcache, void *buf)
142 int i;
144 for (i = 0; i < 23; i++)
145 if (sh_regmap[i] != -1)
146 collect_register (regcache, i, (char *) buf + sh_regmap[i]);
149 static struct regset_info sh_regsets[] = {
150 { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
151 NULL_REGSET
154 static struct regsets_info sh_regsets_info =
156 sh_regsets, /* regsets */
157 0, /* num_regsets */
158 NULL, /* disabled_regsets */
161 static struct usrregs_info sh_usrregs_info =
163 sh_num_regs,
164 sh_regmap,
167 static struct regs_info myregs_info =
169 NULL, /* regset_bitmap */
170 &sh_usrregs_info,
171 &sh_regsets_info
174 const regs_info *
175 sh_target::get_regs_info ()
177 return &myregs_info;
180 void
181 sh_target::low_arch_setup ()
183 current_process ()->tdesc = tdesc_sh;
186 /* The linux target ops object. */
188 linux_process_target *the_linux_target = &the_sh_target;
190 void
191 initialize_low_arch (void)
193 init_registers_sh ();
195 initialize_regsets_info (&sh_regsets_info);