1 /* This test program is part of GDB, the GNU debugger.
3 Copyright 2011-2014 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18 /* Simulate loading of JIT code. */
31 /* ElfW is coming from linux. On other platforms it does not exist.
32 Let us define it here. */
34 # if (defined (_LP64) || defined (__LP64__))
38 # endif /* _LP64 || __LP64__ */
39 #define ElfW(type) _ElfW (Elf, WORDSIZE, type)
40 #define _ElfW(e,w,t) _ElfW_1 (e, w, _##t)
41 #define _ElfW_1(e,w,t) e##w##t
53 struct jit_code_entry *next_entry;
54 struct jit_code_entry *prev_entry;
55 const char *symfile_addr;
56 uint64_t symfile_size;
62 /* This type should be jit_actions_t, but we use uint32_t
63 to be explicit about the bitwidth. */
65 struct jit_code_entry *relevant_entry;
66 struct jit_code_entry *first_entry;
69 /* GDB puts a breakpoint in this function. */
70 void __attribute__((noinline)) __jit_debug_register_code () { }
72 /* Make sure to specify the version statically, because the
73 debugger may check the version before we can set it. */
74 struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 };
77 usage (const char *const argv0)
79 fprintf (stderr, "Usage: %s library [count]\n", argv0);
83 /* Update .p_vaddr and .sh_addr as if the code was JITted to ADDR. */
86 update_locations (const void *const addr, int idx)
88 const ElfW (Ehdr) *const ehdr = (ElfW (Ehdr) *)addr;
89 ElfW (Shdr) *const shdr = (ElfW (Shdr) *)((char *)addr + ehdr->e_shoff);
90 ElfW (Phdr) *const phdr = (ElfW (Phdr) *)((char *)addr + ehdr->e_phoff);
93 for (i = 0; i < ehdr->e_phnum; ++i)
94 if (phdr[i].p_type == PT_LOAD)
95 phdr[i].p_vaddr += (ElfW (Addr))addr;
97 for (i = 0; i < ehdr->e_shnum; ++i)
99 if (shdr[i].sh_type == SHT_STRTAB)
101 /* Note: we update both .strtab and .dynstr. The latter would
102 not be correct if this were a regular shared library (.hash
103 would be wrong), but this is a simulation -- the library is
104 never exposed to the dynamic loader, so it all ends up ok. */
105 char *const strtab = (char *)((ElfW (Addr))addr + shdr[i].sh_offset);
106 char *const strtab_end = strtab + shdr[i].sh_size;
109 for (p = strtab; p < strtab_end; p += strlen (p) + 1)
110 if (strcmp (p, "jit_function_XXXX") == 0)
111 sprintf (p, "jit_function_%04d", idx);
114 if (shdr[i].sh_flags & SHF_ALLOC)
115 shdr[i].sh_addr += (ElfW (Addr))addr;
124 MAIN (int argc, char *argv[])
126 /* These variables are here so they can easily be set from jit.exp. */
127 const char *libname = NULL;
130 count = count; /* gdb break here 0 */
140 /* Only set if not already set from GDB. */
143 if (argc > 2 && count == 0)
144 /* Only set if not already set from GDB. */
145 count = atoi (argv[2]);
147 printf ("%s:%d: libname = %s, count = %d\n", __FILE__, __LINE__,
150 if ((fd = open (libname, O_RDONLY)) == -1)
152 fprintf (stderr, "open (\"%s\", O_RDONLY): %s\n", libname,
157 if (fstat (fd, &st) != 0)
159 fprintf (stderr, "fstat (\"%d\"): %s\n", fd, strerror (errno));
163 for (i = 0; i < count; ++i)
165 const void *const addr = mmap (0, st.st_size, PROT_READ|PROT_WRITE,
167 struct jit_code_entry *const entry = calloc (1, sizeof (*entry));
169 if (addr == MAP_FAILED)
171 fprintf (stderr, "mmap: %s\n", strerror (errno));
175 update_locations (addr, i);
177 /* Link entry at the end of the list. */
178 entry->symfile_addr = (const char *)addr;
179 entry->symfile_size = st.st_size;
180 entry->prev_entry = __jit_debug_descriptor.relevant_entry;
181 __jit_debug_descriptor.relevant_entry = entry;
183 if (entry->prev_entry != NULL)
184 entry->prev_entry->next_entry = entry;
186 __jit_debug_descriptor.first_entry = entry;
189 __jit_debug_descriptor.action_flag = JIT_REGISTER_FN;
190 __jit_debug_register_code ();
193 i = 0; /* gdb break here 1 */
195 /* Now unregister them all in reverse order. */
196 while (__jit_debug_descriptor.relevant_entry != NULL)
198 struct jit_code_entry *const entry =
199 __jit_debug_descriptor.relevant_entry;
200 struct jit_code_entry *const prev_entry = entry->prev_entry;
202 if (prev_entry != NULL)
204 prev_entry->next_entry = NULL;
205 entry->prev_entry = NULL;
208 __jit_debug_descriptor.first_entry = NULL;
211 __jit_debug_descriptor.action_flag = JIT_UNREGISTER_FN;
212 __jit_debug_register_code ();
214 __jit_debug_descriptor.relevant_entry = prev_entry;
218 return 0; /* gdb break here 2 */