| /* Copyright (C) 2009-2018 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include <sys/mman.h> |
| |
| #include JIT_READER_H /* Please see jit-reader.exp for an explanation. */ |
| #include "jithost.h" |
| #include "jit-protocol.h" |
| |
| void __attribute__((noinline)) __jit_debug_register_code () { } |
| |
| struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 }; |
| struct jit_code_entry only_entry; |
| |
| typedef void (jit_function_t) (); |
| |
| /* The code of the jit_function_00 function that is copied into an |
| mmapped buffer in the inferior at run time. |
| |
| The second instruction mangles the stack pointer, meaning that when |
| stopped at the third instruction, GDB needs assistance from the JIT |
| unwinder in order to be able to unwind successfully. */ |
| const unsigned char jit_function_00_code[] = { |
| 0xcc, /* int3 */ |
| 0x48, 0x83, 0xf4, 0xff, /* xor $0xffffffffffffffff, %rsp */ |
| 0x48, 0x83, 0xf4, 0xff, /* xor $0xffffffffffffffff, %rsp */ |
| 0xc3 /* ret */ |
| }; |
| |
| int |
| main (int argc, char **argv) |
| { |
| struct jithost_abi *symfile; |
| char *code = mmap (NULL, getpagesize (), PROT_WRITE | PROT_EXEC, |
| MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| jit_function_t *function = (jit_function_t *) code; |
| |
| memcpy (code, jit_function_00_code, sizeof (jit_function_00_code)); |
| |
| symfile = malloc (sizeof (struct jithost_abi)); |
| symfile->begin = code; |
| symfile->end = code + sizeof (jit_function_00_code); |
| |
| only_entry.symfile_addr = symfile; |
| only_entry.symfile_size = sizeof (struct jithost_abi); |
| |
| __jit_debug_descriptor.first_entry = &only_entry; |
| __jit_debug_descriptor.relevant_entry = &only_entry; |
| __jit_debug_descriptor.action_flag = JIT_REGISTER; |
| __jit_debug_descriptor.version = 1; |
| __jit_debug_register_code (); |
| |
| function (); |
| |
| return 0; |
| } |