gdb/disasm-selftests.c

   1 /* Self tests for disassembler for GDB, the GNU debugger.
   2
   3    Copyright (C) 2017-2021 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "disasm.h"
  22 #include "gdbsupport/selftest.h"
  23 #include "selftest-arch.h"
  24 #include "gdbarch.h"
  25
  26 namespace selftests {
  27
  28 /* Test disassembly of one instruction.  */
  29
  30 static void
  31 print_one_insn_test (struct gdbarch *gdbarch)
  32 {
  33   size_t len = 0;
  34   const gdb_byte *insn = NULL;
  35
  36   switch (gdbarch_bfd_arch_info (gdbarch)->arch)
  37     {
  38     case bfd_arch_bfin:
  39       /* M3.L = 0xe117 */
  40       static const gdb_byte bfin_insn[] = {0x17, 0xe1, 0xff, 0xff};
  41
  42       insn = bfin_insn;
  43       len = sizeof (bfin_insn);
  44       break;
  45     case bfd_arch_arm:
  46       /* mov     r0, #0 */
  47       static const gdb_byte arm_insn[] = {0x0, 0x0, 0xa0, 0xe3};
  48
  49       insn = arm_insn;
  50       len = sizeof (arm_insn);
  51       break;
  52     case bfd_arch_ia64:
  53     case bfd_arch_mep:
  54     case bfd_arch_mips:
  55     case bfd_arch_tic6x:
  56     case bfd_arch_xtensa:
  57       return;
  58     case bfd_arch_s390:
  59       /* nopr %r7 */
  60       static const gdb_byte s390_insn[] = {0x07, 0x07};
  61
  62       insn = s390_insn;
  63       len = sizeof (s390_insn);
  64       break;
  65     case bfd_arch_xstormy16:
  66       /* nop */
  67       static const gdb_byte xstormy16_insn[] = {0x0, 0x0};
  68
  69       insn = xstormy16_insn;
  70       len = sizeof (xstormy16_insn);
  71       break;
  72     case bfd_arch_nios2:
  73     case bfd_arch_score:
  74     case bfd_arch_riscv:
  75       /* nios2, riscv, and score need to know the current instruction
  76          to select breakpoint instruction.  Give the breakpoint
  77          instruction kind explicitly.  */
  78       {
  79         int bplen;
  80         insn = gdbarch_sw_breakpoint_from_kind (gdbarch, 4, &bplen);
  81         len = bplen;
  82       }
  83       break;
  84     case bfd_arch_arc:
  85       /* PR 21003 */
  86       if (gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_arc_arc601)
  87         return;
  88       /* fall through */
  89     default:
  90       {
  91         /* Test disassemble breakpoint instruction.  */
  92         CORE_ADDR pc = 0;
  93         int kind = gdbarch_breakpoint_kind_from_pc (gdbarch, &pc);
  94         int bplen;
  95
  96         insn = gdbarch_sw_breakpoint_from_kind (gdbarch, kind, &bplen);
  97         len = bplen;
  98
  99         break;
 100       }
 101     }
 102   SELF_CHECK (len > 0);
 103
 104   /* Test gdb_disassembler for a given gdbarch by reading data from a
 105      pre-allocated buffer.  If you want to see the disassembled
 106      instruction printed to gdb_stdout, use maint selftest -verbose.  */
 107
 108   class gdb_disassembler_test : public gdb_disassembler
 109   {
 110   public:
 111
 112     explicit gdb_disassembler_test (struct gdbarch *gdbarch,
 113                                     const gdb_byte *insn,
 114                                     size_t len)
 115       : gdb_disassembler (gdbarch,
 116                           (run_verbose () ? gdb_stdout : &null_stream),
 117                           gdb_disassembler_test::read_memory),
 118         m_insn (insn), m_len (len)
 119     {
 120     }
 121
 122     int
 123     print_insn (CORE_ADDR memaddr)
 124     {
 125       if (run_verbose ())
 126         {
 127           fprintf_unfiltered (stream (), "%s ",
 128                               gdbarch_bfd_arch_info (arch ())->arch_name);
 129         }
 130
 131       int len = gdb_disassembler::print_insn (memaddr);
 132
 133       if (run_verbose ())
 134         fprintf_unfiltered (stream (), "\n");
 135
 136       return len;
 137     }
 138
 139   private:
 140     /* A buffer contain one instruction.  */
 141     const gdb_byte *m_insn;
 142
 143     /* Length of the buffer.  */
 144     size_t m_len;
 145
 146     static int read_memory (bfd_vma memaddr, gdb_byte *myaddr,
 147                             unsigned int len, struct disassemble_info *info)
 148     {
 149       gdb_disassembler_test *self
 150         = static_cast<gdb_disassembler_test *>(info->application_data);
 151
 152       /* The disassembler in opcodes may read more data than one
 153          instruction.  Supply infinite consecutive copies
 154          of the same instruction.  */
 155       for (size_t i = 0; i < len; i++)
 156         myaddr[i] = self->m_insn[(memaddr + i) % self->m_len];
 157
 158       return 0;
 159     }
 160   };
 161
 162   gdb_disassembler_test di (gdbarch, insn, len);
 163
 164   SELF_CHECK (di.print_insn (0) == len);
 165 }
 166
 167 /* Test disassembly on memory error.  */
 168
 169 static void
 170 memory_error_test (struct gdbarch *gdbarch)
 171 {
 172   class gdb_disassembler_test : public gdb_disassembler
 173   {
 174   public:
 175     gdb_disassembler_test (struct gdbarch *gdbarch)
 176       : gdb_disassembler (gdbarch, &null_stream,
 177                           gdb_disassembler_test::read_memory)
 178     {
 179     }
 180
 181     static int read_memory (bfd_vma memaddr, gdb_byte *myaddr,
 182                             unsigned int len,
 183                             struct disassemble_info *info)
 184     {
 185       /* Always return an error.  */
 186       return -1;
 187     }
 188   };
 189
 190   gdb_disassembler_test di (gdbarch);
 191   bool saw_memory_error = false;
 192
 193   try
 194     {
 195       di.print_insn (0);
 196     }
 197   catch (const gdb_exception_error &ex)
 198     {
 199       if (ex.error == MEMORY_ERROR)
 200         saw_memory_error = true;
 201     }
 202
 203   /* Expect MEMORY_ERROR.  */
 204   SELF_CHECK (saw_memory_error);
 205 }
 206
 207 } // namespace selftests
 208
 209 void _initialize_disasm_selftests ();
 210 void
 211 _initialize_disasm_selftests ()
 212 {
 213   selftests::register_test_foreach_arch ("print_one_insn",
 214                                          selftests::print_one_insn_test);
 215   selftests::register_test_foreach_arch ("memory_error",
 216                                          selftests::memory_error_test);
 217 }