| 1 | /* Handle JIT code generation in the inferior for GDB, the GNU Debugger. |
| 2 | |
| 3 | Copyright (C) 2009-2015 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 | |
| 22 | #include "jit.h" |
| 23 | #include "jit-reader.h" |
| 24 | #include "block.h" |
| 25 | #include "breakpoint.h" |
| 26 | #include "command.h" |
| 27 | #include "dictionary.h" |
| 28 | #include "filenames.h" |
| 29 | #include "frame-unwind.h" |
| 30 | #include "gdbcmd.h" |
| 31 | #include "gdbcore.h" |
| 32 | #include "inferior.h" |
| 33 | #include "observer.h" |
| 34 | #include "objfiles.h" |
| 35 | #include "regcache.h" |
| 36 | #include "symfile.h" |
| 37 | #include "symtab.h" |
| 38 | #include "target.h" |
| 39 | #include "gdb-dlfcn.h" |
| 40 | #include <sys/stat.h> |
| 41 | #include "gdb_bfd.h" |
| 42 | |
| 43 | static const char *jit_reader_dir = NULL; |
| 44 | |
| 45 | static const struct objfile_data *jit_objfile_data; |
| 46 | |
| 47 | static const char *const jit_break_name = "__jit_debug_register_code"; |
| 48 | |
| 49 | static const char *const jit_descriptor_name = "__jit_debug_descriptor"; |
| 50 | |
| 51 | static const struct program_space_data *jit_program_space_data = NULL; |
| 52 | |
| 53 | static void jit_inferior_init (struct gdbarch *gdbarch); |
| 54 | |
| 55 | /* An unwinder is registered for every gdbarch. This key is used to |
| 56 | remember if the unwinder has been registered for a particular |
| 57 | gdbarch. */ |
| 58 | |
| 59 | static struct gdbarch_data *jit_gdbarch_data; |
| 60 | |
| 61 | /* Non-zero if we want to see trace of jit level stuff. */ |
| 62 | |
| 63 | static unsigned int jit_debug = 0; |
| 64 | |
| 65 | static void |
| 66 | show_jit_debug (struct ui_file *file, int from_tty, |
| 67 | struct cmd_list_element *c, const char *value) |
| 68 | { |
| 69 | fprintf_filtered (file, _("JIT debugging is %s.\n"), value); |
| 70 | } |
| 71 | |
| 72 | struct target_buffer |
| 73 | { |
| 74 | CORE_ADDR base; |
| 75 | ULONGEST size; |
| 76 | }; |
| 77 | |
| 78 | /* Openning the file is a no-op. */ |
| 79 | |
| 80 | static void * |
| 81 | mem_bfd_iovec_open (struct bfd *abfd, void *open_closure) |
| 82 | { |
| 83 | return open_closure; |
| 84 | } |
| 85 | |
| 86 | /* Closing the file is just freeing the base/size pair on our side. */ |
| 87 | |
| 88 | static int |
| 89 | mem_bfd_iovec_close (struct bfd *abfd, void *stream) |
| 90 | { |
| 91 | xfree (stream); |
| 92 | |
| 93 | /* Zero means success. */ |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | /* For reading the file, we just need to pass through to target_read_memory and |
| 98 | fix up the arguments and return values. */ |
| 99 | |
| 100 | static file_ptr |
| 101 | mem_bfd_iovec_pread (struct bfd *abfd, void *stream, void *buf, |
| 102 | file_ptr nbytes, file_ptr offset) |
| 103 | { |
| 104 | int err; |
| 105 | struct target_buffer *buffer = (struct target_buffer *) stream; |
| 106 | |
| 107 | /* If this read will read all of the file, limit it to just the rest. */ |
| 108 | if (offset + nbytes > buffer->size) |
| 109 | nbytes = buffer->size - offset; |
| 110 | |
| 111 | /* If there are no more bytes left, we've reached EOF. */ |
| 112 | if (nbytes == 0) |
| 113 | return 0; |
| 114 | |
| 115 | err = target_read_memory (buffer->base + offset, (gdb_byte *) buf, nbytes); |
| 116 | if (err) |
| 117 | return -1; |
| 118 | |
| 119 | return nbytes; |
| 120 | } |
| 121 | |
| 122 | /* For statting the file, we only support the st_size attribute. */ |
| 123 | |
| 124 | static int |
| 125 | mem_bfd_iovec_stat (struct bfd *abfd, void *stream, struct stat *sb) |
| 126 | { |
| 127 | struct target_buffer *buffer = (struct target_buffer*) stream; |
| 128 | |
| 129 | sb->st_size = buffer->size; |
| 130 | return 0; |
| 131 | } |
| 132 | |
| 133 | /* Open a BFD from the target's memory. */ |
| 134 | |
| 135 | static struct bfd * |
| 136 | bfd_open_from_target_memory (CORE_ADDR addr, ULONGEST size, char *target) |
| 137 | { |
| 138 | struct target_buffer *buffer = xmalloc (sizeof (struct target_buffer)); |
| 139 | |
| 140 | buffer->base = addr; |
| 141 | buffer->size = size; |
| 142 | return gdb_bfd_openr_iovec ("<in-memory>", target, |
| 143 | mem_bfd_iovec_open, |
| 144 | buffer, |
| 145 | mem_bfd_iovec_pread, |
| 146 | mem_bfd_iovec_close, |
| 147 | mem_bfd_iovec_stat); |
| 148 | } |
| 149 | |
| 150 | /* One reader that has been loaded successfully, and can potentially be used to |
| 151 | parse debug info. */ |
| 152 | |
| 153 | static struct jit_reader |
| 154 | { |
| 155 | struct gdb_reader_funcs *functions; |
| 156 | void *handle; |
| 157 | } *loaded_jit_reader = NULL; |
| 158 | |
| 159 | typedef struct gdb_reader_funcs * (reader_init_fn_type) (void); |
| 160 | static const char *reader_init_fn_sym = "gdb_init_reader"; |
| 161 | |
| 162 | /* Try to load FILE_NAME as a JIT debug info reader. */ |
| 163 | |
| 164 | static struct jit_reader * |
| 165 | jit_reader_load (const char *file_name) |
| 166 | { |
| 167 | void *so; |
| 168 | reader_init_fn_type *init_fn; |
| 169 | struct jit_reader *new_reader = NULL; |
| 170 | struct gdb_reader_funcs *funcs = NULL; |
| 171 | struct cleanup *old_cleanups; |
| 172 | |
| 173 | if (jit_debug) |
| 174 | fprintf_unfiltered (gdb_stdlog, _("Opening shared object %s.\n"), |
| 175 | file_name); |
| 176 | so = gdb_dlopen (file_name); |
| 177 | old_cleanups = make_cleanup_dlclose (so); |
| 178 | |
| 179 | init_fn = gdb_dlsym (so, reader_init_fn_sym); |
| 180 | if (!init_fn) |
| 181 | error (_("Could not locate initialization function: %s."), |
| 182 | reader_init_fn_sym); |
| 183 | |
| 184 | if (gdb_dlsym (so, "plugin_is_GPL_compatible") == NULL) |
| 185 | error (_("Reader not GPL compatible.")); |
| 186 | |
| 187 | funcs = init_fn (); |
| 188 | if (funcs->reader_version != GDB_READER_INTERFACE_VERSION) |
| 189 | error (_("Reader version does not match GDB version.")); |
| 190 | |
| 191 | new_reader = XCNEW (struct jit_reader); |
| 192 | new_reader->functions = funcs; |
| 193 | new_reader->handle = so; |
| 194 | |
| 195 | discard_cleanups (old_cleanups); |
| 196 | return new_reader; |
| 197 | } |
| 198 | |
| 199 | /* Provides the jit-reader-load command. */ |
| 200 | |
| 201 | static void |
| 202 | jit_reader_load_command (char *args, int from_tty) |
| 203 | { |
| 204 | char *so_name; |
| 205 | struct cleanup *prev_cleanup; |
| 206 | |
| 207 | if (args == NULL) |
| 208 | error (_("No reader name provided.")); |
| 209 | |
| 210 | if (loaded_jit_reader != NULL) |
| 211 | error (_("JIT reader already loaded. Run jit-reader-unload first.")); |
| 212 | |
| 213 | if (IS_ABSOLUTE_PATH (args)) |
| 214 | so_name = xstrdup (args); |
| 215 | else |
| 216 | so_name = xstrprintf ("%s%s%s", jit_reader_dir, SLASH_STRING, args); |
| 217 | prev_cleanup = make_cleanup (xfree, so_name); |
| 218 | |
| 219 | loaded_jit_reader = jit_reader_load (so_name); |
| 220 | do_cleanups (prev_cleanup); |
| 221 | } |
| 222 | |
| 223 | /* Provides the jit-reader-unload command. */ |
| 224 | |
| 225 | static void |
| 226 | jit_reader_unload_command (char *args, int from_tty) |
| 227 | { |
| 228 | if (!loaded_jit_reader) |
| 229 | error (_("No JIT reader loaded.")); |
| 230 | |
| 231 | loaded_jit_reader->functions->destroy (loaded_jit_reader->functions); |
| 232 | |
| 233 | gdb_dlclose (loaded_jit_reader->handle); |
| 234 | xfree (loaded_jit_reader); |
| 235 | loaded_jit_reader = NULL; |
| 236 | } |
| 237 | |
| 238 | /* Per-program space structure recording which objfile has the JIT |
| 239 | symbols. */ |
| 240 | |
| 241 | struct jit_program_space_data |
| 242 | { |
| 243 | /* The objfile. This is NULL if no objfile holds the JIT |
| 244 | symbols. */ |
| 245 | |
| 246 | struct objfile *objfile; |
| 247 | |
| 248 | /* If this program space has __jit_debug_register_code, this is the |
| 249 | cached address from the minimal symbol. This is used to detect |
| 250 | relocations requiring the breakpoint to be re-created. */ |
| 251 | |
| 252 | CORE_ADDR cached_code_address; |
| 253 | |
| 254 | /* This is the JIT event breakpoint, or NULL if it has not been |
| 255 | set. */ |
| 256 | |
| 257 | struct breakpoint *jit_breakpoint; |
| 258 | }; |
| 259 | |
| 260 | /* Per-objfile structure recording the addresses in the program space. |
| 261 | This object serves two purposes: for ordinary objfiles, it may |
| 262 | cache some symbols related to the JIT interface; and for |
| 263 | JIT-created objfiles, it holds some information about the |
| 264 | jit_code_entry. */ |
| 265 | |
| 266 | struct jit_objfile_data |
| 267 | { |
| 268 | /* Symbol for __jit_debug_register_code. */ |
| 269 | struct minimal_symbol *register_code; |
| 270 | |
| 271 | /* Symbol for __jit_debug_descriptor. */ |
| 272 | struct minimal_symbol *descriptor; |
| 273 | |
| 274 | /* Address of struct jit_code_entry in this objfile. This is only |
| 275 | non-zero for objfiles that represent code created by the JIT. */ |
| 276 | CORE_ADDR addr; |
| 277 | }; |
| 278 | |
| 279 | /* Fetch the jit_objfile_data associated with OBJF. If no data exists |
| 280 | yet, make a new structure and attach it. */ |
| 281 | |
| 282 | static struct jit_objfile_data * |
| 283 | get_jit_objfile_data (struct objfile *objf) |
| 284 | { |
| 285 | struct jit_objfile_data *objf_data; |
| 286 | |
| 287 | objf_data = objfile_data (objf, jit_objfile_data); |
| 288 | if (objf_data == NULL) |
| 289 | { |
| 290 | objf_data = XCNEW (struct jit_objfile_data); |
| 291 | set_objfile_data (objf, jit_objfile_data, objf_data); |
| 292 | } |
| 293 | |
| 294 | return objf_data; |
| 295 | } |
| 296 | |
| 297 | /* Remember OBJFILE has been created for struct jit_code_entry located |
| 298 | at inferior address ENTRY. */ |
| 299 | |
| 300 | static void |
| 301 | add_objfile_entry (struct objfile *objfile, CORE_ADDR entry) |
| 302 | { |
| 303 | struct jit_objfile_data *objf_data; |
| 304 | |
| 305 | objf_data = get_jit_objfile_data (objfile); |
| 306 | objf_data->addr = entry; |
| 307 | } |
| 308 | |
| 309 | /* Return jit_program_space_data for current program space. Allocate |
| 310 | if not already present. */ |
| 311 | |
| 312 | static struct jit_program_space_data * |
| 313 | get_jit_program_space_data (void) |
| 314 | { |
| 315 | struct jit_program_space_data *ps_data; |
| 316 | |
| 317 | ps_data = program_space_data (current_program_space, jit_program_space_data); |
| 318 | if (ps_data == NULL) |
| 319 | { |
| 320 | ps_data = XCNEW (struct jit_program_space_data); |
| 321 | set_program_space_data (current_program_space, jit_program_space_data, |
| 322 | ps_data); |
| 323 | } |
| 324 | |
| 325 | return ps_data; |
| 326 | } |
| 327 | |
| 328 | static void |
| 329 | jit_program_space_data_cleanup (struct program_space *ps, void *arg) |
| 330 | { |
| 331 | xfree (arg); |
| 332 | } |
| 333 | |
| 334 | /* Helper function for reading the global JIT descriptor from remote |
| 335 | memory. Returns 1 if all went well, 0 otherwise. */ |
| 336 | |
| 337 | static int |
| 338 | jit_read_descriptor (struct gdbarch *gdbarch, |
| 339 | struct jit_descriptor *descriptor, |
| 340 | struct jit_program_space_data *ps_data) |
| 341 | { |
| 342 | int err; |
| 343 | struct type *ptr_type; |
| 344 | int ptr_size; |
| 345 | int desc_size; |
| 346 | gdb_byte *desc_buf; |
| 347 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 348 | struct jit_objfile_data *objf_data; |
| 349 | |
| 350 | if (ps_data->objfile == NULL) |
| 351 | return 0; |
| 352 | objf_data = get_jit_objfile_data (ps_data->objfile); |
| 353 | if (objf_data->descriptor == NULL) |
| 354 | return 0; |
| 355 | |
| 356 | if (jit_debug) |
| 357 | fprintf_unfiltered (gdb_stdlog, |
| 358 | "jit_read_descriptor, descriptor_addr = %s\n", |
| 359 | paddress (gdbarch, MSYMBOL_VALUE_ADDRESS (ps_data->objfile, |
| 360 | objf_data->descriptor))); |
| 361 | |
| 362 | /* Figure out how big the descriptor is on the remote and how to read it. */ |
| 363 | ptr_type = builtin_type (gdbarch)->builtin_data_ptr; |
| 364 | ptr_size = TYPE_LENGTH (ptr_type); |
| 365 | desc_size = 8 + 2 * ptr_size; /* Two 32-bit ints and two pointers. */ |
| 366 | desc_buf = alloca (desc_size); |
| 367 | |
| 368 | /* Read the descriptor. */ |
| 369 | err = target_read_memory (MSYMBOL_VALUE_ADDRESS (ps_data->objfile, |
| 370 | objf_data->descriptor), |
| 371 | desc_buf, desc_size); |
| 372 | if (err) |
| 373 | { |
| 374 | printf_unfiltered (_("Unable to read JIT descriptor from " |
| 375 | "remote memory\n")); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | /* Fix the endianness to match the host. */ |
| 380 | descriptor->version = extract_unsigned_integer (&desc_buf[0], 4, byte_order); |
| 381 | descriptor->action_flag = |
| 382 | extract_unsigned_integer (&desc_buf[4], 4, byte_order); |
| 383 | descriptor->relevant_entry = extract_typed_address (&desc_buf[8], ptr_type); |
| 384 | descriptor->first_entry = |
| 385 | extract_typed_address (&desc_buf[8 + ptr_size], ptr_type); |
| 386 | |
| 387 | return 1; |
| 388 | } |
| 389 | |
| 390 | /* Helper function for reading a JITed code entry from remote memory. */ |
| 391 | |
| 392 | static void |
| 393 | jit_read_code_entry (struct gdbarch *gdbarch, |
| 394 | CORE_ADDR code_addr, struct jit_code_entry *code_entry) |
| 395 | { |
| 396 | int err, off; |
| 397 | struct type *ptr_type; |
| 398 | int ptr_size; |
| 399 | int entry_size; |
| 400 | int align_bytes; |
| 401 | gdb_byte *entry_buf; |
| 402 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 403 | |
| 404 | /* Figure out how big the entry is on the remote and how to read it. */ |
| 405 | ptr_type = builtin_type (gdbarch)->builtin_data_ptr; |
| 406 | ptr_size = TYPE_LENGTH (ptr_type); |
| 407 | |
| 408 | /* Figure out where the longlong value will be. */ |
| 409 | align_bytes = gdbarch_long_long_align_bit (gdbarch) / 8; |
| 410 | off = 3 * ptr_size; |
| 411 | off = (off + (align_bytes - 1)) & ~(align_bytes - 1); |
| 412 | |
| 413 | entry_size = off + 8; /* Three pointers and one 64-bit int. */ |
| 414 | entry_buf = alloca (entry_size); |
| 415 | |
| 416 | /* Read the entry. */ |
| 417 | err = target_read_memory (code_addr, entry_buf, entry_size); |
| 418 | if (err) |
| 419 | error (_("Unable to read JIT code entry from remote memory!")); |
| 420 | |
| 421 | /* Fix the endianness to match the host. */ |
| 422 | ptr_type = builtin_type (gdbarch)->builtin_data_ptr; |
| 423 | code_entry->next_entry = extract_typed_address (&entry_buf[0], ptr_type); |
| 424 | code_entry->prev_entry = |
| 425 | extract_typed_address (&entry_buf[ptr_size], ptr_type); |
| 426 | code_entry->symfile_addr = |
| 427 | extract_typed_address (&entry_buf[2 * ptr_size], ptr_type); |
| 428 | code_entry->symfile_size = |
| 429 | extract_unsigned_integer (&entry_buf[off], 8, byte_order); |
| 430 | } |
| 431 | |
| 432 | /* Proxy object for building a block. */ |
| 433 | |
| 434 | struct gdb_block |
| 435 | { |
| 436 | /* gdb_blocks are linked into a tree structure. Next points to the |
| 437 | next node at the same depth as this block and parent to the |
| 438 | parent gdb_block. */ |
| 439 | struct gdb_block *next, *parent; |
| 440 | |
| 441 | /* Points to the "real" block that is being built out of this |
| 442 | instance. This block will be added to a blockvector, which will |
| 443 | then be added to a symtab. */ |
| 444 | struct block *real_block; |
| 445 | |
| 446 | /* The first and last code address corresponding to this block. */ |
| 447 | CORE_ADDR begin, end; |
| 448 | |
| 449 | /* The name of this block (if any). If this is non-NULL, the |
| 450 | FUNCTION symbol symbol is set to this value. */ |
| 451 | const char *name; |
| 452 | }; |
| 453 | |
| 454 | /* Proxy object for building a symtab. */ |
| 455 | |
| 456 | struct gdb_symtab |
| 457 | { |
| 458 | /* The list of blocks in this symtab. These will eventually be |
| 459 | converted to real blocks. */ |
| 460 | struct gdb_block *blocks; |
| 461 | |
| 462 | /* The number of blocks inserted. */ |
| 463 | int nblocks; |
| 464 | |
| 465 | /* A mapping between line numbers to PC. */ |
| 466 | struct linetable *linetable; |
| 467 | |
| 468 | /* The source file for this symtab. */ |
| 469 | const char *file_name; |
| 470 | struct gdb_symtab *next; |
| 471 | }; |
| 472 | |
| 473 | /* Proxy object for building an object. */ |
| 474 | |
| 475 | struct gdb_object |
| 476 | { |
| 477 | struct gdb_symtab *symtabs; |
| 478 | }; |
| 479 | |
| 480 | /* The type of the `private' data passed around by the callback |
| 481 | functions. */ |
| 482 | |
| 483 | typedef CORE_ADDR jit_dbg_reader_data; |
| 484 | |
| 485 | /* The reader calls into this function to read data off the targets |
| 486 | address space. */ |
| 487 | |
| 488 | static enum gdb_status |
| 489 | jit_target_read_impl (GDB_CORE_ADDR target_mem, void *gdb_buf, int len) |
| 490 | { |
| 491 | int result = target_read_memory ((CORE_ADDR) target_mem, gdb_buf, len); |
| 492 | if (result == 0) |
| 493 | return GDB_SUCCESS; |
| 494 | else |
| 495 | return GDB_FAIL; |
| 496 | } |
| 497 | |
| 498 | /* The reader calls into this function to create a new gdb_object |
| 499 | which it can then pass around to the other callbacks. Right now, |
| 500 | all that is required is allocating the memory. */ |
| 501 | |
| 502 | static struct gdb_object * |
| 503 | jit_object_open_impl (struct gdb_symbol_callbacks *cb) |
| 504 | { |
| 505 | /* CB is not required right now, but sometime in the future we might |
| 506 | need a handle to it, and we'd like to do that without breaking |
| 507 | the ABI. */ |
| 508 | return XCNEW (struct gdb_object); |
| 509 | } |
| 510 | |
| 511 | /* Readers call into this function to open a new gdb_symtab, which, |
| 512 | again, is passed around to other callbacks. */ |
| 513 | |
| 514 | static struct gdb_symtab * |
| 515 | jit_symtab_open_impl (struct gdb_symbol_callbacks *cb, |
| 516 | struct gdb_object *object, |
| 517 | const char *file_name) |
| 518 | { |
| 519 | struct gdb_symtab *ret; |
| 520 | |
| 521 | /* CB stays unused. See comment in jit_object_open_impl. */ |
| 522 | |
| 523 | ret = XCNEW (struct gdb_symtab); |
| 524 | ret->file_name = file_name ? xstrdup (file_name) : xstrdup (""); |
| 525 | ret->next = object->symtabs; |
| 526 | object->symtabs = ret; |
| 527 | return ret; |
| 528 | } |
| 529 | |
| 530 | /* Returns true if the block corresponding to old should be placed |
| 531 | before the block corresponding to new in the final blockvector. */ |
| 532 | |
| 533 | static int |
| 534 | compare_block (const struct gdb_block *const old, |
| 535 | const struct gdb_block *const new) |
| 536 | { |
| 537 | if (old == NULL) |
| 538 | return 1; |
| 539 | if (old->begin < new->begin) |
| 540 | return 1; |
| 541 | else if (old->begin == new->begin) |
| 542 | { |
| 543 | if (old->end > new->end) |
| 544 | return 1; |
| 545 | else |
| 546 | return 0; |
| 547 | } |
| 548 | else |
| 549 | return 0; |
| 550 | } |
| 551 | |
| 552 | /* Called by readers to open a new gdb_block. This function also |
| 553 | inserts the new gdb_block in the correct place in the corresponding |
| 554 | gdb_symtab. */ |
| 555 | |
| 556 | static struct gdb_block * |
| 557 | jit_block_open_impl (struct gdb_symbol_callbacks *cb, |
| 558 | struct gdb_symtab *symtab, struct gdb_block *parent, |
| 559 | GDB_CORE_ADDR begin, GDB_CORE_ADDR end, const char *name) |
| 560 | { |
| 561 | struct gdb_block *block = XCNEW (struct gdb_block); |
| 562 | |
| 563 | block->next = symtab->blocks; |
| 564 | block->begin = (CORE_ADDR) begin; |
| 565 | block->end = (CORE_ADDR) end; |
| 566 | block->name = name ? xstrdup (name) : NULL; |
| 567 | block->parent = parent; |
| 568 | |
| 569 | /* Ensure that the blocks are inserted in the correct (reverse of |
| 570 | the order expected by blockvector). */ |
| 571 | if (compare_block (symtab->blocks, block)) |
| 572 | { |
| 573 | symtab->blocks = block; |
| 574 | } |
| 575 | else |
| 576 | { |
| 577 | struct gdb_block *i = symtab->blocks; |
| 578 | |
| 579 | for (;; i = i->next) |
| 580 | { |
| 581 | /* Guaranteed to terminate, since compare_block (NULL, _) |
| 582 | returns 1. */ |
| 583 | if (compare_block (i->next, block)) |
| 584 | { |
| 585 | block->next = i->next; |
| 586 | i->next = block; |
| 587 | break; |
| 588 | } |
| 589 | } |
| 590 | } |
| 591 | symtab->nblocks++; |
| 592 | |
| 593 | return block; |
| 594 | } |
| 595 | |
| 596 | /* Readers call this to add a line mapping (from PC to line number) to |
| 597 | a gdb_symtab. */ |
| 598 | |
| 599 | static void |
| 600 | jit_symtab_line_mapping_add_impl (struct gdb_symbol_callbacks *cb, |
| 601 | struct gdb_symtab *stab, int nlines, |
| 602 | struct gdb_line_mapping *map) |
| 603 | { |
| 604 | int i; |
| 605 | |
| 606 | if (nlines < 1) |
| 607 | return; |
| 608 | |
| 609 | stab->linetable = xmalloc (sizeof (struct linetable) |
| 610 | + (nlines - 1) * sizeof (struct linetable_entry)); |
| 611 | stab->linetable->nitems = nlines; |
| 612 | for (i = 0; i < nlines; i++) |
| 613 | { |
| 614 | stab->linetable->item[i].pc = (CORE_ADDR) map[i].pc; |
| 615 | stab->linetable->item[i].line = map[i].line; |
| 616 | } |
| 617 | } |
| 618 | |
| 619 | /* Called by readers to close a gdb_symtab. Does not need to do |
| 620 | anything as of now. */ |
| 621 | |
| 622 | static void |
| 623 | jit_symtab_close_impl (struct gdb_symbol_callbacks *cb, |
| 624 | struct gdb_symtab *stab) |
| 625 | { |
| 626 | /* Right now nothing needs to be done here. We may need to do some |
| 627 | cleanup here in the future (again, without breaking the plugin |
| 628 | ABI). */ |
| 629 | } |
| 630 | |
| 631 | /* Transform STAB to a proper symtab, and add it it OBJFILE. */ |
| 632 | |
| 633 | static void |
| 634 | finalize_symtab (struct gdb_symtab *stab, struct objfile *objfile) |
| 635 | { |
| 636 | struct compunit_symtab *cust; |
| 637 | struct gdb_block *gdb_block_iter, *gdb_block_iter_tmp; |
| 638 | struct block *block_iter; |
| 639 | int actual_nblocks, i; |
| 640 | size_t blockvector_size; |
| 641 | CORE_ADDR begin, end; |
| 642 | struct blockvector *bv; |
| 643 | |
| 644 | actual_nblocks = FIRST_LOCAL_BLOCK + stab->nblocks; |
| 645 | |
| 646 | cust = allocate_compunit_symtab (objfile, stab->file_name); |
| 647 | allocate_symtab (cust, stab->file_name); |
| 648 | add_compunit_symtab_to_objfile (cust); |
| 649 | |
| 650 | /* JIT compilers compile in memory. */ |
| 651 | COMPUNIT_DIRNAME (cust) = NULL; |
| 652 | |
| 653 | /* Copy over the linetable entry if one was provided. */ |
| 654 | if (stab->linetable) |
| 655 | { |
| 656 | size_t size = ((stab->linetable->nitems - 1) |
| 657 | * sizeof (struct linetable_entry) |
| 658 | + sizeof (struct linetable)); |
| 659 | SYMTAB_LINETABLE (COMPUNIT_FILETABS (cust)) |
| 660 | = obstack_alloc (&objfile->objfile_obstack, size); |
| 661 | memcpy (SYMTAB_LINETABLE (COMPUNIT_FILETABS (cust)), stab->linetable, |
| 662 | size); |
| 663 | } |
| 664 | |
| 665 | blockvector_size = (sizeof (struct blockvector) |
| 666 | + (actual_nblocks - 1) * sizeof (struct block *)); |
| 667 | bv = obstack_alloc (&objfile->objfile_obstack, blockvector_size); |
| 668 | COMPUNIT_BLOCKVECTOR (cust) = bv; |
| 669 | |
| 670 | /* (begin, end) will contain the PC range this entire blockvector |
| 671 | spans. */ |
| 672 | BLOCKVECTOR_MAP (bv) = NULL; |
| 673 | begin = stab->blocks->begin; |
| 674 | end = stab->blocks->end; |
| 675 | BLOCKVECTOR_NBLOCKS (bv) = actual_nblocks; |
| 676 | |
| 677 | /* First run over all the gdb_block objects, creating a real block |
| 678 | object for each. Simultaneously, keep setting the real_block |
| 679 | fields. */ |
| 680 | for (i = (actual_nblocks - 1), gdb_block_iter = stab->blocks; |
| 681 | i >= FIRST_LOCAL_BLOCK; |
| 682 | i--, gdb_block_iter = gdb_block_iter->next) |
| 683 | { |
| 684 | struct block *new_block = allocate_block (&objfile->objfile_obstack); |
| 685 | struct symbol *block_name = allocate_symbol (objfile); |
| 686 | struct type *block_type = arch_type (get_objfile_arch (objfile), |
| 687 | TYPE_CODE_VOID, |
| 688 | 1, |
| 689 | "void"); |
| 690 | |
| 691 | BLOCK_DICT (new_block) = dict_create_linear (&objfile->objfile_obstack, |
| 692 | NULL); |
| 693 | /* The address range. */ |
| 694 | BLOCK_START (new_block) = (CORE_ADDR) gdb_block_iter->begin; |
| 695 | BLOCK_END (new_block) = (CORE_ADDR) gdb_block_iter->end; |
| 696 | |
| 697 | /* The name. */ |
| 698 | SYMBOL_DOMAIN (block_name) = VAR_DOMAIN; |
| 699 | SYMBOL_ACLASS_INDEX (block_name) = LOC_BLOCK; |
| 700 | symbol_set_symtab (block_name, COMPUNIT_FILETABS (cust)); |
| 701 | SYMBOL_TYPE (block_name) = lookup_function_type (block_type); |
| 702 | SYMBOL_BLOCK_VALUE (block_name) = new_block; |
| 703 | |
| 704 | block_name->ginfo.name = obstack_copy0 (&objfile->objfile_obstack, |
| 705 | gdb_block_iter->name, |
| 706 | strlen (gdb_block_iter->name)); |
| 707 | |
| 708 | BLOCK_FUNCTION (new_block) = block_name; |
| 709 | |
| 710 | BLOCKVECTOR_BLOCK (bv, i) = new_block; |
| 711 | if (begin > BLOCK_START (new_block)) |
| 712 | begin = BLOCK_START (new_block); |
| 713 | if (end < BLOCK_END (new_block)) |
| 714 | end = BLOCK_END (new_block); |
| 715 | |
| 716 | gdb_block_iter->real_block = new_block; |
| 717 | } |
| 718 | |
| 719 | /* Now add the special blocks. */ |
| 720 | block_iter = NULL; |
| 721 | for (i = 0; i < FIRST_LOCAL_BLOCK; i++) |
| 722 | { |
| 723 | struct block *new_block; |
| 724 | |
| 725 | new_block = (i == GLOBAL_BLOCK |
| 726 | ? allocate_global_block (&objfile->objfile_obstack) |
| 727 | : allocate_block (&objfile->objfile_obstack)); |
| 728 | BLOCK_DICT (new_block) = dict_create_linear (&objfile->objfile_obstack, |
| 729 | NULL); |
| 730 | BLOCK_SUPERBLOCK (new_block) = block_iter; |
| 731 | block_iter = new_block; |
| 732 | |
| 733 | BLOCK_START (new_block) = (CORE_ADDR) begin; |
| 734 | BLOCK_END (new_block) = (CORE_ADDR) end; |
| 735 | |
| 736 | BLOCKVECTOR_BLOCK (bv, i) = new_block; |
| 737 | |
| 738 | if (i == GLOBAL_BLOCK) |
| 739 | set_block_compunit_symtab (new_block, cust); |
| 740 | } |
| 741 | |
| 742 | /* Fill up the superblock fields for the real blocks, using the |
| 743 | real_block fields populated earlier. */ |
| 744 | for (gdb_block_iter = stab->blocks; |
| 745 | gdb_block_iter; |
| 746 | gdb_block_iter = gdb_block_iter->next) |
| 747 | { |
| 748 | if (gdb_block_iter->parent != NULL) |
| 749 | { |
| 750 | /* If the plugin specifically mentioned a parent block, we |
| 751 | use that. */ |
| 752 | BLOCK_SUPERBLOCK (gdb_block_iter->real_block) = |
| 753 | gdb_block_iter->parent->real_block; |
| 754 | } |
| 755 | else |
| 756 | { |
| 757 | /* And if not, we set a default parent block. */ |
| 758 | BLOCK_SUPERBLOCK (gdb_block_iter->real_block) = |
| 759 | BLOCKVECTOR_BLOCK (bv, STATIC_BLOCK); |
| 760 | } |
| 761 | } |
| 762 | |
| 763 | /* Free memory. */ |
| 764 | gdb_block_iter = stab->blocks; |
| 765 | |
| 766 | for (gdb_block_iter = stab->blocks, gdb_block_iter_tmp = gdb_block_iter->next; |
| 767 | gdb_block_iter; |
| 768 | gdb_block_iter = gdb_block_iter_tmp) |
| 769 | { |
| 770 | xfree ((void *) gdb_block_iter->name); |
| 771 | xfree (gdb_block_iter); |
| 772 | } |
| 773 | xfree (stab->linetable); |
| 774 | xfree ((char *) stab->file_name); |
| 775 | xfree (stab); |
| 776 | } |
| 777 | |
| 778 | /* Called when closing a gdb_objfile. Converts OBJ to a proper |
| 779 | objfile. */ |
| 780 | |
| 781 | static void |
| 782 | jit_object_close_impl (struct gdb_symbol_callbacks *cb, |
| 783 | struct gdb_object *obj) |
| 784 | { |
| 785 | struct gdb_symtab *i, *j; |
| 786 | struct objfile *objfile; |
| 787 | jit_dbg_reader_data *priv_data; |
| 788 | |
| 789 | priv_data = cb->priv_data; |
| 790 | |
| 791 | objfile = allocate_objfile (NULL, "<< JIT compiled code >>", |
| 792 | OBJF_NOT_FILENAME); |
| 793 | objfile->per_bfd->gdbarch = target_gdbarch (); |
| 794 | |
| 795 | terminate_minimal_symbol_table (objfile); |
| 796 | |
| 797 | j = NULL; |
| 798 | for (i = obj->symtabs; i; i = j) |
| 799 | { |
| 800 | j = i->next; |
| 801 | finalize_symtab (i, objfile); |
| 802 | } |
| 803 | add_objfile_entry (objfile, *priv_data); |
| 804 | xfree (obj); |
| 805 | } |
| 806 | |
| 807 | /* Try to read CODE_ENTRY using the loaded jit reader (if any). |
| 808 | ENTRY_ADDR is the address of the struct jit_code_entry in the |
| 809 | inferior address space. */ |
| 810 | |
| 811 | static int |
| 812 | jit_reader_try_read_symtab (struct jit_code_entry *code_entry, |
| 813 | CORE_ADDR entry_addr) |
| 814 | { |
| 815 | void *gdb_mem; |
| 816 | int status; |
| 817 | jit_dbg_reader_data priv_data; |
| 818 | struct gdb_reader_funcs *funcs; |
| 819 | volatile struct gdb_exception e; |
| 820 | struct gdb_symbol_callbacks callbacks = |
| 821 | { |
| 822 | jit_object_open_impl, |
| 823 | jit_symtab_open_impl, |
| 824 | jit_block_open_impl, |
| 825 | jit_symtab_close_impl, |
| 826 | jit_object_close_impl, |
| 827 | |
| 828 | jit_symtab_line_mapping_add_impl, |
| 829 | jit_target_read_impl, |
| 830 | |
| 831 | &priv_data |
| 832 | }; |
| 833 | |
| 834 | priv_data = entry_addr; |
| 835 | |
| 836 | if (!loaded_jit_reader) |
| 837 | return 0; |
| 838 | |
| 839 | gdb_mem = xmalloc (code_entry->symfile_size); |
| 840 | |
| 841 | status = 1; |
| 842 | TRY_CATCH (e, RETURN_MASK_ALL) |
| 843 | if (target_read_memory (code_entry->symfile_addr, gdb_mem, |
| 844 | code_entry->symfile_size)) |
| 845 | status = 0; |
| 846 | if (e.reason < 0) |
| 847 | status = 0; |
| 848 | |
| 849 | if (status) |
| 850 | { |
| 851 | funcs = loaded_jit_reader->functions; |
| 852 | if (funcs->read (funcs, &callbacks, gdb_mem, code_entry->symfile_size) |
| 853 | != GDB_SUCCESS) |
| 854 | status = 0; |
| 855 | } |
| 856 | |
| 857 | xfree (gdb_mem); |
| 858 | if (jit_debug && status == 0) |
| 859 | fprintf_unfiltered (gdb_stdlog, |
| 860 | "Could not read symtab using the loaded JIT reader.\n"); |
| 861 | return status; |
| 862 | } |
| 863 | |
| 864 | /* Try to read CODE_ENTRY using BFD. ENTRY_ADDR is the address of the |
| 865 | struct jit_code_entry in the inferior address space. */ |
| 866 | |
| 867 | static void |
| 868 | jit_bfd_try_read_symtab (struct jit_code_entry *code_entry, |
| 869 | CORE_ADDR entry_addr, |
| 870 | struct gdbarch *gdbarch) |
| 871 | { |
| 872 | bfd *nbfd; |
| 873 | struct section_addr_info *sai; |
| 874 | struct bfd_section *sec; |
| 875 | struct objfile *objfile; |
| 876 | struct cleanup *old_cleanups; |
| 877 | int i; |
| 878 | const struct bfd_arch_info *b; |
| 879 | |
| 880 | if (jit_debug) |
| 881 | fprintf_unfiltered (gdb_stdlog, |
| 882 | "jit_register_code, symfile_addr = %s, " |
| 883 | "symfile_size = %s\n", |
| 884 | paddress (gdbarch, code_entry->symfile_addr), |
| 885 | pulongest (code_entry->symfile_size)); |
| 886 | |
| 887 | nbfd = bfd_open_from_target_memory (code_entry->symfile_addr, |
| 888 | code_entry->symfile_size, gnutarget); |
| 889 | if (nbfd == NULL) |
| 890 | { |
| 891 | puts_unfiltered (_("Error opening JITed symbol file, ignoring it.\n")); |
| 892 | return; |
| 893 | } |
| 894 | |
| 895 | /* Check the format. NOTE: This initializes important data that GDB uses! |
| 896 | We would segfault later without this line. */ |
| 897 | if (!bfd_check_format (nbfd, bfd_object)) |
| 898 | { |
| 899 | printf_unfiltered (_("\ |
| 900 | JITed symbol file is not an object file, ignoring it.\n")); |
| 901 | gdb_bfd_unref (nbfd); |
| 902 | return; |
| 903 | } |
| 904 | |
| 905 | /* Check bfd arch. */ |
| 906 | b = gdbarch_bfd_arch_info (gdbarch); |
| 907 | if (b->compatible (b, bfd_get_arch_info (nbfd)) != b) |
| 908 | warning (_("JITed object file architecture %s is not compatible " |
| 909 | "with target architecture %s."), bfd_get_arch_info |
| 910 | (nbfd)->printable_name, b->printable_name); |
| 911 | |
| 912 | /* Read the section address information out of the symbol file. Since the |
| 913 | file is generated by the JIT at runtime, it should all of the absolute |
| 914 | addresses that we care about. */ |
| 915 | sai = alloc_section_addr_info (bfd_count_sections (nbfd)); |
| 916 | old_cleanups = make_cleanup_free_section_addr_info (sai); |
| 917 | i = 0; |
| 918 | for (sec = nbfd->sections; sec != NULL; sec = sec->next) |
| 919 | if ((bfd_get_section_flags (nbfd, sec) & (SEC_ALLOC|SEC_LOAD)) != 0) |
| 920 | { |
| 921 | /* We assume that these virtual addresses are absolute, and do not |
| 922 | treat them as offsets. */ |
| 923 | sai->other[i].addr = bfd_get_section_vma (nbfd, sec); |
| 924 | sai->other[i].name = xstrdup (bfd_get_section_name (nbfd, sec)); |
| 925 | sai->other[i].sectindex = sec->index; |
| 926 | ++i; |
| 927 | } |
| 928 | sai->num_sections = i; |
| 929 | |
| 930 | /* This call does not take ownership of SAI. */ |
| 931 | make_cleanup_bfd_unref (nbfd); |
| 932 | objfile = symbol_file_add_from_bfd (nbfd, bfd_get_filename (nbfd), 0, sai, |
| 933 | OBJF_SHARED | OBJF_NOT_FILENAME, NULL); |
| 934 | |
| 935 | do_cleanups (old_cleanups); |
| 936 | add_objfile_entry (objfile, entry_addr); |
| 937 | } |
| 938 | |
| 939 | /* This function registers code associated with a JIT code entry. It uses the |
| 940 | pointer and size pair in the entry to read the symbol file from the remote |
| 941 | and then calls symbol_file_add_from_local_memory to add it as though it were |
| 942 | a symbol file added by the user. */ |
| 943 | |
| 944 | static void |
| 945 | jit_register_code (struct gdbarch *gdbarch, |
| 946 | CORE_ADDR entry_addr, struct jit_code_entry *code_entry) |
| 947 | { |
| 948 | int success; |
| 949 | |
| 950 | if (jit_debug) |
| 951 | fprintf_unfiltered (gdb_stdlog, |
| 952 | "jit_register_code, symfile_addr = %s, " |
| 953 | "symfile_size = %s\n", |
| 954 | paddress (gdbarch, code_entry->symfile_addr), |
| 955 | pulongest (code_entry->symfile_size)); |
| 956 | |
| 957 | success = jit_reader_try_read_symtab (code_entry, entry_addr); |
| 958 | |
| 959 | if (!success) |
| 960 | jit_bfd_try_read_symtab (code_entry, entry_addr, gdbarch); |
| 961 | } |
| 962 | |
| 963 | /* This function unregisters JITed code and frees the corresponding |
| 964 | objfile. */ |
| 965 | |
| 966 | static void |
| 967 | jit_unregister_code (struct objfile *objfile) |
| 968 | { |
| 969 | free_objfile (objfile); |
| 970 | } |
| 971 | |
| 972 | /* Look up the objfile with this code entry address. */ |
| 973 | |
| 974 | static struct objfile * |
| 975 | jit_find_objf_with_entry_addr (CORE_ADDR entry_addr) |
| 976 | { |
| 977 | struct objfile *objf; |
| 978 | |
| 979 | ALL_OBJFILES (objf) |
| 980 | { |
| 981 | struct jit_objfile_data *objf_data; |
| 982 | |
| 983 | objf_data = objfile_data (objf, jit_objfile_data); |
| 984 | if (objf_data != NULL && objf_data->addr == entry_addr) |
| 985 | return objf; |
| 986 | } |
| 987 | return NULL; |
| 988 | } |
| 989 | |
| 990 | /* This is called when a breakpoint is deleted. It updates the |
| 991 | inferior's cache, if needed. */ |
| 992 | |
| 993 | static void |
| 994 | jit_breakpoint_deleted (struct breakpoint *b) |
| 995 | { |
| 996 | struct bp_location *iter; |
| 997 | |
| 998 | if (b->type != bp_jit_event) |
| 999 | return; |
| 1000 | |
| 1001 | for (iter = b->loc; iter != NULL; iter = iter->next) |
| 1002 | { |
| 1003 | struct jit_program_space_data *ps_data; |
| 1004 | |
| 1005 | ps_data = program_space_data (iter->pspace, jit_program_space_data); |
| 1006 | if (ps_data != NULL && ps_data->jit_breakpoint == iter->owner) |
| 1007 | { |
| 1008 | ps_data->cached_code_address = 0; |
| 1009 | ps_data->jit_breakpoint = NULL; |
| 1010 | } |
| 1011 | } |
| 1012 | } |
| 1013 | |
| 1014 | /* (Re-)Initialize the jit breakpoint if necessary. |
| 1015 | Return 0 on success. */ |
| 1016 | |
| 1017 | static int |
| 1018 | jit_breakpoint_re_set_internal (struct gdbarch *gdbarch, |
| 1019 | struct jit_program_space_data *ps_data) |
| 1020 | { |
| 1021 | struct bound_minimal_symbol reg_symbol; |
| 1022 | struct bound_minimal_symbol desc_symbol; |
| 1023 | struct jit_objfile_data *objf_data; |
| 1024 | CORE_ADDR addr; |
| 1025 | |
| 1026 | if (ps_data->objfile == NULL) |
| 1027 | { |
| 1028 | /* Lookup the registration symbol. If it is missing, then we |
| 1029 | assume we are not attached to a JIT. */ |
| 1030 | reg_symbol = lookup_minimal_symbol_and_objfile (jit_break_name); |
| 1031 | if (reg_symbol.minsym == NULL |
| 1032 | || BMSYMBOL_VALUE_ADDRESS (reg_symbol) == 0) |
| 1033 | return 1; |
| 1034 | |
| 1035 | desc_symbol = lookup_minimal_symbol (jit_descriptor_name, NULL, |
| 1036 | reg_symbol.objfile); |
| 1037 | if (desc_symbol.minsym == NULL |
| 1038 | || BMSYMBOL_VALUE_ADDRESS (desc_symbol) == 0) |
| 1039 | return 1; |
| 1040 | |
| 1041 | objf_data = get_jit_objfile_data (reg_symbol.objfile); |
| 1042 | objf_data->register_code = reg_symbol.minsym; |
| 1043 | objf_data->descriptor = desc_symbol.minsym; |
| 1044 | |
| 1045 | ps_data->objfile = reg_symbol.objfile; |
| 1046 | } |
| 1047 | else |
| 1048 | objf_data = get_jit_objfile_data (ps_data->objfile); |
| 1049 | |
| 1050 | addr = MSYMBOL_VALUE_ADDRESS (ps_data->objfile, objf_data->register_code); |
| 1051 | |
| 1052 | if (jit_debug) |
| 1053 | fprintf_unfiltered (gdb_stdlog, |
| 1054 | "jit_breakpoint_re_set_internal, " |
| 1055 | "breakpoint_addr = %s\n", |
| 1056 | paddress (gdbarch, addr)); |
| 1057 | |
| 1058 | if (ps_data->cached_code_address == addr) |
| 1059 | return 1; |
| 1060 | |
| 1061 | /* Delete the old breakpoint. */ |
| 1062 | if (ps_data->jit_breakpoint != NULL) |
| 1063 | delete_breakpoint (ps_data->jit_breakpoint); |
| 1064 | |
| 1065 | /* Put a breakpoint in the registration symbol. */ |
| 1066 | ps_data->cached_code_address = addr; |
| 1067 | ps_data->jit_breakpoint = create_jit_event_breakpoint (gdbarch, addr); |
| 1068 | |
| 1069 | return 0; |
| 1070 | } |
| 1071 | |
| 1072 | /* The private data passed around in the frame unwind callback |
| 1073 | functions. */ |
| 1074 | |
| 1075 | struct jit_unwind_private |
| 1076 | { |
| 1077 | /* Cached register values. See jit_frame_sniffer to see how this |
| 1078 | works. */ |
| 1079 | struct gdb_reg_value **registers; |
| 1080 | |
| 1081 | /* The frame being unwound. */ |
| 1082 | struct frame_info *this_frame; |
| 1083 | }; |
| 1084 | |
| 1085 | /* Sets the value of a particular register in this frame. */ |
| 1086 | |
| 1087 | static void |
| 1088 | jit_unwind_reg_set_impl (struct gdb_unwind_callbacks *cb, int dwarf_regnum, |
| 1089 | struct gdb_reg_value *value) |
| 1090 | { |
| 1091 | struct jit_unwind_private *priv; |
| 1092 | int gdb_reg; |
| 1093 | |
| 1094 | priv = cb->priv_data; |
| 1095 | |
| 1096 | gdb_reg = gdbarch_dwarf2_reg_to_regnum (get_frame_arch (priv->this_frame), |
| 1097 | dwarf_regnum); |
| 1098 | if (gdb_reg == -1) |
| 1099 | { |
| 1100 | if (jit_debug) |
| 1101 | fprintf_unfiltered (gdb_stdlog, |
| 1102 | _("Could not recognize DWARF regnum %d"), |
| 1103 | dwarf_regnum); |
| 1104 | return; |
| 1105 | } |
| 1106 | |
| 1107 | gdb_assert (priv->registers); |
| 1108 | priv->registers[gdb_reg] = value; |
| 1109 | } |
| 1110 | |
| 1111 | static void |
| 1112 | reg_value_free_impl (struct gdb_reg_value *value) |
| 1113 | { |
| 1114 | xfree (value); |
| 1115 | } |
| 1116 | |
| 1117 | /* Get the value of register REGNUM in the previous frame. */ |
| 1118 | |
| 1119 | static struct gdb_reg_value * |
| 1120 | jit_unwind_reg_get_impl (struct gdb_unwind_callbacks *cb, int regnum) |
| 1121 | { |
| 1122 | struct jit_unwind_private *priv; |
| 1123 | struct gdb_reg_value *value; |
| 1124 | int gdb_reg, size; |
| 1125 | struct gdbarch *frame_arch; |
| 1126 | |
| 1127 | priv = cb->priv_data; |
| 1128 | frame_arch = get_frame_arch (priv->this_frame); |
| 1129 | |
| 1130 | gdb_reg = gdbarch_dwarf2_reg_to_regnum (frame_arch, regnum); |
| 1131 | size = register_size (frame_arch, gdb_reg); |
| 1132 | value = xmalloc (sizeof (struct gdb_reg_value) + size - 1); |
| 1133 | value->defined = deprecated_frame_register_read (priv->this_frame, gdb_reg, |
| 1134 | value->value); |
| 1135 | value->size = size; |
| 1136 | value->free = reg_value_free_impl; |
| 1137 | return value; |
| 1138 | } |
| 1139 | |
| 1140 | /* gdb_reg_value has a free function, which must be called on each |
| 1141 | saved register value. */ |
| 1142 | |
| 1143 | static void |
| 1144 | jit_dealloc_cache (struct frame_info *this_frame, void *cache) |
| 1145 | { |
| 1146 | struct jit_unwind_private *priv_data = cache; |
| 1147 | struct gdbarch *frame_arch; |
| 1148 | int i; |
| 1149 | |
| 1150 | gdb_assert (priv_data->registers); |
| 1151 | frame_arch = get_frame_arch (priv_data->this_frame); |
| 1152 | |
| 1153 | for (i = 0; i < gdbarch_num_regs (frame_arch); i++) |
| 1154 | if (priv_data->registers[i] && priv_data->registers[i]->free) |
| 1155 | priv_data->registers[i]->free (priv_data->registers[i]); |
| 1156 | |
| 1157 | xfree (priv_data->registers); |
| 1158 | xfree (priv_data); |
| 1159 | } |
| 1160 | |
| 1161 | /* The frame sniffer for the pseudo unwinder. |
| 1162 | |
| 1163 | While this is nominally a frame sniffer, in the case where the JIT |
| 1164 | reader actually recognizes the frame, it does a lot more work -- it |
| 1165 | unwinds the frame and saves the corresponding register values in |
| 1166 | the cache. jit_frame_prev_register simply returns the saved |
| 1167 | register values. */ |
| 1168 | |
| 1169 | static int |
| 1170 | jit_frame_sniffer (const struct frame_unwind *self, |
| 1171 | struct frame_info *this_frame, void **cache) |
| 1172 | { |
| 1173 | struct jit_unwind_private *priv_data; |
| 1174 | struct gdb_unwind_callbacks callbacks; |
| 1175 | struct gdb_reader_funcs *funcs; |
| 1176 | |
| 1177 | callbacks.reg_get = jit_unwind_reg_get_impl; |
| 1178 | callbacks.reg_set = jit_unwind_reg_set_impl; |
| 1179 | callbacks.target_read = jit_target_read_impl; |
| 1180 | |
| 1181 | if (loaded_jit_reader == NULL) |
| 1182 | return 0; |
| 1183 | |
| 1184 | funcs = loaded_jit_reader->functions; |
| 1185 | |
| 1186 | gdb_assert (!*cache); |
| 1187 | |
| 1188 | *cache = XCNEW (struct jit_unwind_private); |
| 1189 | priv_data = *cache; |
| 1190 | priv_data->registers = |
| 1191 | XCNEWVEC (struct gdb_reg_value *, |
| 1192 | gdbarch_num_regs (get_frame_arch (this_frame))); |
| 1193 | priv_data->this_frame = this_frame; |
| 1194 | |
| 1195 | callbacks.priv_data = priv_data; |
| 1196 | |
| 1197 | /* Try to coax the provided unwinder to unwind the stack */ |
| 1198 | if (funcs->unwind (funcs, &callbacks) == GDB_SUCCESS) |
| 1199 | { |
| 1200 | if (jit_debug) |
| 1201 | fprintf_unfiltered (gdb_stdlog, _("Successfully unwound frame using " |
| 1202 | "JIT reader.\n")); |
| 1203 | return 1; |
| 1204 | } |
| 1205 | if (jit_debug) |
| 1206 | fprintf_unfiltered (gdb_stdlog, _("Could not unwind frame using " |
| 1207 | "JIT reader.\n")); |
| 1208 | |
| 1209 | jit_dealloc_cache (this_frame, *cache); |
| 1210 | *cache = NULL; |
| 1211 | |
| 1212 | return 0; |
| 1213 | } |
| 1214 | |
| 1215 | |
| 1216 | /* The frame_id function for the pseudo unwinder. Relays the call to |
| 1217 | the loaded plugin. */ |
| 1218 | |
| 1219 | static void |
| 1220 | jit_frame_this_id (struct frame_info *this_frame, void **cache, |
| 1221 | struct frame_id *this_id) |
| 1222 | { |
| 1223 | struct jit_unwind_private private; |
| 1224 | struct gdb_frame_id frame_id; |
| 1225 | struct gdb_reader_funcs *funcs; |
| 1226 | struct gdb_unwind_callbacks callbacks; |
| 1227 | |
| 1228 | private.registers = NULL; |
| 1229 | private.this_frame = this_frame; |
| 1230 | |
| 1231 | /* We don't expect the frame_id function to set any registers, so we |
| 1232 | set reg_set to NULL. */ |
| 1233 | callbacks.reg_get = jit_unwind_reg_get_impl; |
| 1234 | callbacks.reg_set = NULL; |
| 1235 | callbacks.target_read = jit_target_read_impl; |
| 1236 | callbacks.priv_data = &private; |
| 1237 | |
| 1238 | gdb_assert (loaded_jit_reader); |
| 1239 | funcs = loaded_jit_reader->functions; |
| 1240 | |
| 1241 | frame_id = funcs->get_frame_id (funcs, &callbacks); |
| 1242 | *this_id = frame_id_build (frame_id.stack_address, frame_id.code_address); |
| 1243 | } |
| 1244 | |
| 1245 | /* Pseudo unwinder function. Reads the previously fetched value for |
| 1246 | the register from the cache. */ |
| 1247 | |
| 1248 | static struct value * |
| 1249 | jit_frame_prev_register (struct frame_info *this_frame, void **cache, int reg) |
| 1250 | { |
| 1251 | struct jit_unwind_private *priv = *cache; |
| 1252 | struct gdb_reg_value *value; |
| 1253 | |
| 1254 | if (priv == NULL) |
| 1255 | return frame_unwind_got_optimized (this_frame, reg); |
| 1256 | |
| 1257 | gdb_assert (priv->registers); |
| 1258 | value = priv->registers[reg]; |
| 1259 | if (value && value->defined) |
| 1260 | return frame_unwind_got_bytes (this_frame, reg, value->value); |
| 1261 | else |
| 1262 | return frame_unwind_got_optimized (this_frame, reg); |
| 1263 | } |
| 1264 | |
| 1265 | /* Relay everything back to the unwinder registered by the JIT debug |
| 1266 | info reader.*/ |
| 1267 | |
| 1268 | static const struct frame_unwind jit_frame_unwind = |
| 1269 | { |
| 1270 | NORMAL_FRAME, |
| 1271 | default_frame_unwind_stop_reason, |
| 1272 | jit_frame_this_id, |
| 1273 | jit_frame_prev_register, |
| 1274 | NULL, |
| 1275 | jit_frame_sniffer, |
| 1276 | jit_dealloc_cache |
| 1277 | }; |
| 1278 | |
| 1279 | |
| 1280 | /* This is the information that is stored at jit_gdbarch_data for each |
| 1281 | architecture. */ |
| 1282 | |
| 1283 | struct jit_gdbarch_data_type |
| 1284 | { |
| 1285 | /* Has the (pseudo) unwinder been prepended? */ |
| 1286 | int unwinder_registered; |
| 1287 | }; |
| 1288 | |
| 1289 | /* Check GDBARCH and prepend the pseudo JIT unwinder if needed. */ |
| 1290 | |
| 1291 | static void |
| 1292 | jit_prepend_unwinder (struct gdbarch *gdbarch) |
| 1293 | { |
| 1294 | struct jit_gdbarch_data_type *data; |
| 1295 | |
| 1296 | data = gdbarch_data (gdbarch, jit_gdbarch_data); |
| 1297 | if (!data->unwinder_registered) |
| 1298 | { |
| 1299 | frame_unwind_prepend_unwinder (gdbarch, &jit_frame_unwind); |
| 1300 | data->unwinder_registered = 1; |
| 1301 | } |
| 1302 | } |
| 1303 | |
| 1304 | /* Register any already created translations. */ |
| 1305 | |
| 1306 | static void |
| 1307 | jit_inferior_init (struct gdbarch *gdbarch) |
| 1308 | { |
| 1309 | struct jit_descriptor descriptor; |
| 1310 | struct jit_code_entry cur_entry; |
| 1311 | struct jit_program_space_data *ps_data; |
| 1312 | CORE_ADDR cur_entry_addr; |
| 1313 | |
| 1314 | if (jit_debug) |
| 1315 | fprintf_unfiltered (gdb_stdlog, "jit_inferior_init\n"); |
| 1316 | |
| 1317 | jit_prepend_unwinder (gdbarch); |
| 1318 | |
| 1319 | ps_data = get_jit_program_space_data (); |
| 1320 | if (jit_breakpoint_re_set_internal (gdbarch, ps_data) != 0) |
| 1321 | return; |
| 1322 | |
| 1323 | /* Read the descriptor so we can check the version number and load |
| 1324 | any already JITed functions. */ |
| 1325 | if (!jit_read_descriptor (gdbarch, &descriptor, ps_data)) |
| 1326 | return; |
| 1327 | |
| 1328 | /* Check that the version number agrees with that we support. */ |
| 1329 | if (descriptor.version != 1) |
| 1330 | { |
| 1331 | printf_unfiltered (_("Unsupported JIT protocol version %ld " |
| 1332 | "in descriptor (expected 1)\n"), |
| 1333 | (long) descriptor.version); |
| 1334 | return; |
| 1335 | } |
| 1336 | |
| 1337 | /* If we've attached to a running program, we need to check the descriptor |
| 1338 | to register any functions that were already generated. */ |
| 1339 | for (cur_entry_addr = descriptor.first_entry; |
| 1340 | cur_entry_addr != 0; |
| 1341 | cur_entry_addr = cur_entry.next_entry) |
| 1342 | { |
| 1343 | jit_read_code_entry (gdbarch, cur_entry_addr, &cur_entry); |
| 1344 | |
| 1345 | /* This hook may be called many times during setup, so make sure we don't |
| 1346 | add the same symbol file twice. */ |
| 1347 | if (jit_find_objf_with_entry_addr (cur_entry_addr) != NULL) |
| 1348 | continue; |
| 1349 | |
| 1350 | jit_register_code (gdbarch, cur_entry_addr, &cur_entry); |
| 1351 | } |
| 1352 | } |
| 1353 | |
| 1354 | /* Exported routine to call when an inferior has been created. */ |
| 1355 | |
| 1356 | void |
| 1357 | jit_inferior_created_hook (void) |
| 1358 | { |
| 1359 | jit_inferior_init (target_gdbarch ()); |
| 1360 | } |
| 1361 | |
| 1362 | /* Exported routine to call to re-set the jit breakpoints, |
| 1363 | e.g. when a program is rerun. */ |
| 1364 | |
| 1365 | void |
| 1366 | jit_breakpoint_re_set (void) |
| 1367 | { |
| 1368 | jit_breakpoint_re_set_internal (target_gdbarch (), |
| 1369 | get_jit_program_space_data ()); |
| 1370 | } |
| 1371 | |
| 1372 | /* This function cleans up any code entries left over when the |
| 1373 | inferior exits. We get left over code when the inferior exits |
| 1374 | without unregistering its code, for example when it crashes. */ |
| 1375 | |
| 1376 | static void |
| 1377 | jit_inferior_exit_hook (struct inferior *inf) |
| 1378 | { |
| 1379 | struct objfile *objf; |
| 1380 | struct objfile *temp; |
| 1381 | |
| 1382 | ALL_OBJFILES_SAFE (objf, temp) |
| 1383 | { |
| 1384 | struct jit_objfile_data *objf_data = objfile_data (objf, |
| 1385 | jit_objfile_data); |
| 1386 | |
| 1387 | if (objf_data != NULL && objf_data->addr != 0) |
| 1388 | jit_unregister_code (objf); |
| 1389 | } |
| 1390 | } |
| 1391 | |
| 1392 | void |
| 1393 | jit_event_handler (struct gdbarch *gdbarch) |
| 1394 | { |
| 1395 | struct jit_descriptor descriptor; |
| 1396 | struct jit_code_entry code_entry; |
| 1397 | CORE_ADDR entry_addr; |
| 1398 | struct objfile *objf; |
| 1399 | |
| 1400 | /* Read the descriptor from remote memory. */ |
| 1401 | if (!jit_read_descriptor (gdbarch, &descriptor, |
| 1402 | get_jit_program_space_data ())) |
| 1403 | return; |
| 1404 | entry_addr = descriptor.relevant_entry; |
| 1405 | |
| 1406 | /* Do the corresponding action. */ |
| 1407 | switch (descriptor.action_flag) |
| 1408 | { |
| 1409 | case JIT_NOACTION: |
| 1410 | break; |
| 1411 | case JIT_REGISTER: |
| 1412 | jit_read_code_entry (gdbarch, entry_addr, &code_entry); |
| 1413 | jit_register_code (gdbarch, entry_addr, &code_entry); |
| 1414 | break; |
| 1415 | case JIT_UNREGISTER: |
| 1416 | objf = jit_find_objf_with_entry_addr (entry_addr); |
| 1417 | if (objf == NULL) |
| 1418 | printf_unfiltered (_("Unable to find JITed code " |
| 1419 | "entry at address: %s\n"), |
| 1420 | paddress (gdbarch, entry_addr)); |
| 1421 | else |
| 1422 | jit_unregister_code (objf); |
| 1423 | |
| 1424 | break; |
| 1425 | default: |
| 1426 | error (_("Unknown action_flag value in JIT descriptor!")); |
| 1427 | break; |
| 1428 | } |
| 1429 | } |
| 1430 | |
| 1431 | /* Called to free the data allocated to the jit_program_space_data slot. */ |
| 1432 | |
| 1433 | static void |
| 1434 | free_objfile_data (struct objfile *objfile, void *data) |
| 1435 | { |
| 1436 | struct jit_objfile_data *objf_data = data; |
| 1437 | |
| 1438 | if (objf_data->register_code != NULL) |
| 1439 | { |
| 1440 | struct jit_program_space_data *ps_data; |
| 1441 | |
| 1442 | ps_data = program_space_data (objfile->pspace, jit_program_space_data); |
| 1443 | if (ps_data != NULL && ps_data->objfile == objfile) |
| 1444 | ps_data->objfile = NULL; |
| 1445 | } |
| 1446 | |
| 1447 | xfree (data); |
| 1448 | } |
| 1449 | |
| 1450 | /* Initialize the jit_gdbarch_data slot with an instance of struct |
| 1451 | jit_gdbarch_data_type */ |
| 1452 | |
| 1453 | static void * |
| 1454 | jit_gdbarch_data_init (struct obstack *obstack) |
| 1455 | { |
| 1456 | struct jit_gdbarch_data_type *data; |
| 1457 | |
| 1458 | data = obstack_alloc (obstack, sizeof (struct jit_gdbarch_data_type)); |
| 1459 | data->unwinder_registered = 0; |
| 1460 | return data; |
| 1461 | } |
| 1462 | |
| 1463 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 1464 | |
| 1465 | extern void _initialize_jit (void); |
| 1466 | |
| 1467 | void |
| 1468 | _initialize_jit (void) |
| 1469 | { |
| 1470 | jit_reader_dir = relocate_gdb_directory (JIT_READER_DIR, |
| 1471 | JIT_READER_DIR_RELOCATABLE); |
| 1472 | add_setshow_zuinteger_cmd ("jit", class_maintenance, &jit_debug, |
| 1473 | _("Set JIT debugging."), |
| 1474 | _("Show JIT debugging."), |
| 1475 | _("When non-zero, JIT debugging is enabled."), |
| 1476 | NULL, |
| 1477 | show_jit_debug, |
| 1478 | &setdebuglist, &showdebuglist); |
| 1479 | |
| 1480 | observer_attach_inferior_exit (jit_inferior_exit_hook); |
| 1481 | observer_attach_breakpoint_deleted (jit_breakpoint_deleted); |
| 1482 | |
| 1483 | jit_objfile_data = |
| 1484 | register_objfile_data_with_cleanup (NULL, free_objfile_data); |
| 1485 | jit_program_space_data = |
| 1486 | register_program_space_data_with_cleanup (NULL, |
| 1487 | jit_program_space_data_cleanup); |
| 1488 | jit_gdbarch_data = gdbarch_data_register_pre_init (jit_gdbarch_data_init); |
| 1489 | if (is_dl_available ()) |
| 1490 | { |
| 1491 | add_com ("jit-reader-load", no_class, jit_reader_load_command, _("\ |
| 1492 | Load FILE as debug info reader and unwinder for JIT compiled code.\n\ |
| 1493 | Usage: jit-reader-load FILE\n\ |
| 1494 | Try to load file FILE as a debug info reader (and unwinder) for\n\ |
| 1495 | JIT compiled code. The file is loaded from " JIT_READER_DIR ",\n\ |
| 1496 | relocated relative to the GDB executable if required.")); |
| 1497 | add_com ("jit-reader-unload", no_class, jit_reader_unload_command, _("\ |
| 1498 | Unload the currently loaded JIT debug info reader.\n\ |
| 1499 | Usage: jit-reader-unload FILE\n\n\ |
| 1500 | Do \"help jit-reader-load\" for info on loading debug info readers.")); |
| 1501 | } |
| 1502 | } |