1 /* Handle JIT code generation in the inferior for GDB, the GNU Debugger.
3 Copyright (C) 2009-2012 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
23 #include "jit-reader.h"
25 #include "breakpoint.h"
27 #include "dictionary.h"
28 #include "frame-unwind.h"
38 #include "gdb-dlfcn.h"
40 #include "exceptions.h"
42 static const char *jit_reader_dir = NULL;
44 static const struct objfile_data *jit_objfile_data;
46 static const char *const jit_break_name = "__jit_debug_register_code";
48 static const char *const jit_descriptor_name = "__jit_debug_descriptor";
50 static const struct inferior_data *jit_inferior_data = NULL;
52 static void jit_inferior_init (struct gdbarch *gdbarch);
54 /* An unwinder is registered for every gdbarch. This key is used to
55 remember if the unwinder has been registered for a particular
58 static struct gdbarch_data *jit_gdbarch_data;
60 /* Non-zero if we want to see trace of jit level stuff. */
62 static int jit_debug = 0;
65 show_jit_debug (struct ui_file *file, int from_tty,
66 struct cmd_list_element *c, const char *value)
68 fprintf_filtered (file, _("JIT debugging is %s.\n"), value);
77 /* Openning the file is a no-op. */
80 mem_bfd_iovec_open (struct bfd *abfd, void *open_closure)
85 /* Closing the file is just freeing the base/size pair on our side. */
88 mem_bfd_iovec_close (struct bfd *abfd, void *stream)
94 /* For reading the file, we just need to pass through to target_read_memory and
95 fix up the arguments and return values. */
98 mem_bfd_iovec_pread (struct bfd *abfd, void *stream, void *buf,
99 file_ptr nbytes, file_ptr offset)
102 struct target_buffer *buffer = (struct target_buffer *) stream;
104 /* If this read will read all of the file, limit it to just the rest. */
105 if (offset + nbytes > buffer->size)
106 nbytes = buffer->size - offset;
108 /* If there are no more bytes left, we've reached EOF. */
112 err = target_read_memory (buffer->base + offset, (gdb_byte *) buf, nbytes);
119 /* For statting the file, we only support the st_size attribute. */
122 mem_bfd_iovec_stat (struct bfd *abfd, void *stream, struct stat *sb)
124 struct target_buffer *buffer = (struct target_buffer*) stream;
126 sb->st_size = buffer->size;
130 /* Open a BFD from the target's memory. */
133 bfd_open_from_target_memory (CORE_ADDR addr, ULONGEST size, char *target)
135 const char *filename = xstrdup ("<in-memory>");
136 struct target_buffer *buffer = xmalloc (sizeof (struct target_buffer));
140 return bfd_openr_iovec (filename, target,
148 /* One reader that has been loaded successfully, and can potentially be used to
151 static struct jit_reader
153 struct gdb_reader_funcs *functions;
155 } *loaded_jit_reader = NULL;
157 typedef struct gdb_reader_funcs * (reader_init_fn_type) (void);
158 static const char *reader_init_fn_sym = "gdb_init_reader";
160 /* Try to load FILE_NAME as a JIT debug info reader. */
162 static struct jit_reader *
163 jit_reader_load (const char *file_name)
166 reader_init_fn_type *init_fn;
167 struct jit_reader *new_reader = NULL;
168 struct gdb_reader_funcs *funcs = NULL;
169 struct cleanup *old_cleanups;
172 fprintf_unfiltered (gdb_stdlog, _("Opening shared object %s.\n"),
174 so = gdb_dlopen (file_name);
175 old_cleanups = make_cleanup_dlclose (so);
177 init_fn = gdb_dlsym (so, reader_init_fn_sym);
179 error (_("Could not locate initialization function: %s."),
182 if (gdb_dlsym (so, "plugin_is_GPL_compatible") == NULL)
183 error (_("Reader not GPL compatible."));
186 if (funcs->reader_version != GDB_READER_INTERFACE_VERSION)
187 error (_("Reader version does not match GDB version."));
189 new_reader = XZALLOC (struct jit_reader);
190 new_reader->functions = funcs;
191 new_reader->handle = so;
193 discard_cleanups (old_cleanups);
197 /* Provides the jit-reader-load command. */
200 jit_reader_load_command (char *args, int from_tty)
204 struct cleanup *prev_cleanup;
207 error (_("No reader name provided."));
209 if (loaded_jit_reader != NULL)
210 error (_("JIT reader already loaded. Run jit-reader-unload first."));
212 so_name = xstrprintf ("%s/%s", jit_reader_dir, args);
213 prev_cleanup = make_cleanup (xfree, so_name);
215 loaded_jit_reader = jit_reader_load (so_name);
216 do_cleanups (prev_cleanup);
219 /* Provides the jit-reader-unload command. */
222 jit_reader_unload_command (char *args, int from_tty)
224 if (!loaded_jit_reader)
225 error (_("No JIT reader loaded."));
227 loaded_jit_reader->functions->destroy (loaded_jit_reader->functions);
229 gdb_dlclose (loaded_jit_reader->handle);
230 xfree (loaded_jit_reader);
231 loaded_jit_reader = NULL;
234 /* Per-inferior structure recording which objfile has the JIT
237 struct jit_inferior_data
239 /* The objfile. This is NULL if no objfile holds the JIT
242 struct objfile *objfile;
245 /* Per-objfile structure recording the addresses in the inferior. */
247 struct jit_objfile_data
249 /* Symbol for __jit_debug_register_code. */
250 struct minimal_symbol *register_code;
252 /* Symbol for __jit_debug_descriptor. */
253 struct minimal_symbol *descriptor;
255 /* Address of struct jit_code_entry in this objfile. */
259 /* Fetch the jit_objfile_data associated with OBJF. If no data exists
260 yet, make a new structure and attach it. */
262 static struct jit_objfile_data *
263 get_jit_objfile_data (struct objfile *objf)
265 struct jit_objfile_data *objf_data;
267 objf_data = objfile_data (objf, jit_objfile_data);
268 if (objf_data == NULL)
270 objf_data = XZALLOC (struct jit_objfile_data);
271 set_objfile_data (objf, jit_objfile_data, objf_data);
277 /* Remember OBJFILE has been created for struct jit_code_entry located
278 at inferior address ENTRY. */
281 add_objfile_entry (struct objfile *objfile, CORE_ADDR entry)
283 CORE_ADDR *entry_addr_ptr;
284 struct jit_objfile_data *objf_data;
286 objf_data = get_jit_objfile_data (objfile);
287 objf_data->addr = entry;
290 /* Return jit_inferior_data for current inferior. Allocate if not already
293 static struct jit_inferior_data *
294 get_jit_inferior_data (void)
296 struct inferior *inf;
297 struct jit_inferior_data *inf_data;
299 inf = current_inferior ();
300 inf_data = inferior_data (inf, jit_inferior_data);
301 if (inf_data == NULL)
303 inf_data = XZALLOC (struct jit_inferior_data);
304 set_inferior_data (inf, jit_inferior_data, inf_data);
311 jit_inferior_data_cleanup (struct inferior *inf, void *arg)
316 /* Helper function for reading the global JIT descriptor from remote
317 memory. Returns 1 if all went well, 0 otherwise. */
320 jit_read_descriptor (struct gdbarch *gdbarch,
321 struct jit_descriptor *descriptor,
322 struct jit_inferior_data *inf_data)
325 struct type *ptr_type;
329 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
330 struct jit_objfile_data *objf_data;
332 if (inf_data->objfile == NULL)
334 objf_data = get_jit_objfile_data (inf_data->objfile);
335 if (objf_data->descriptor == NULL)
339 fprintf_unfiltered (gdb_stdlog,
340 "jit_read_descriptor, descriptor_addr = %s\n",
341 paddress (gdbarch, SYMBOL_VALUE_ADDRESS (objf_data->descriptor)));
343 /* Figure out how big the descriptor is on the remote and how to read it. */
344 ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
345 ptr_size = TYPE_LENGTH (ptr_type);
346 desc_size = 8 + 2 * ptr_size; /* Two 32-bit ints and two pointers. */
347 desc_buf = alloca (desc_size);
349 /* Read the descriptor. */
350 err = target_read_memory (SYMBOL_VALUE_ADDRESS (objf_data->descriptor),
351 desc_buf, desc_size);
354 printf_unfiltered (_("Unable to read JIT descriptor from "
359 /* Fix the endianness to match the host. */
360 descriptor->version = extract_unsigned_integer (&desc_buf[0], 4, byte_order);
361 descriptor->action_flag =
362 extract_unsigned_integer (&desc_buf[4], 4, byte_order);
363 descriptor->relevant_entry = extract_typed_address (&desc_buf[8], ptr_type);
364 descriptor->first_entry =
365 extract_typed_address (&desc_buf[8 + ptr_size], ptr_type);
370 /* Helper function for reading a JITed code entry from remote memory. */
373 jit_read_code_entry (struct gdbarch *gdbarch,
374 CORE_ADDR code_addr, struct jit_code_entry *code_entry)
377 struct type *ptr_type;
382 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
384 /* Figure out how big the entry is on the remote and how to read it. */
385 ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
386 ptr_size = TYPE_LENGTH (ptr_type);
388 /* Figure out where the longlong value will be. */
389 align_bytes = gdbarch_long_long_align_bit (gdbarch) / 8;
391 off = (off + (align_bytes - 1)) & ~(align_bytes - 1);
393 entry_size = off + 8; /* Three pointers and one 64-bit int. */
394 entry_buf = alloca (entry_size);
396 /* Read the entry. */
397 err = target_read_memory (code_addr, entry_buf, entry_size);
399 error (_("Unable to read JIT code entry from remote memory!"));
401 /* Fix the endianness to match the host. */
402 ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
403 code_entry->next_entry = extract_typed_address (&entry_buf[0], ptr_type);
404 code_entry->prev_entry =
405 extract_typed_address (&entry_buf[ptr_size], ptr_type);
406 code_entry->symfile_addr =
407 extract_typed_address (&entry_buf[2 * ptr_size], ptr_type);
408 code_entry->symfile_size =
409 extract_unsigned_integer (&entry_buf[off], 8, byte_order);
412 /* Proxy object for building a block. */
416 /* gdb_blocks are linked into a tree structure. Next points to the
417 next node at the same depth as this block and parent to the
419 struct gdb_block *next, *parent;
421 /* Points to the "real" block that is being built out of this
422 instance. This block will be added to a blockvector, which will
423 then be added to a symtab. */
424 struct block *real_block;
426 /* The first and last code address corresponding to this block. */
427 CORE_ADDR begin, end;
429 /* The name of this block (if any). If this is non-NULL, the
430 FUNCTION symbol symbol is set to this value. */
434 /* Proxy object for building a symtab. */
438 /* The list of blocks in this symtab. These will eventually be
439 converted to real blocks. */
440 struct gdb_block *blocks;
442 /* The number of blocks inserted. */
445 /* A mapping between line numbers to PC. */
446 struct linetable *linetable;
448 /* The source file for this symtab. */
449 const char *file_name;
450 struct gdb_symtab *next;
453 /* Proxy object for building an object. */
457 struct gdb_symtab *symtabs;
460 /* The type of the `private' data passed around by the callback
463 typedef CORE_ADDR jit_dbg_reader_data;
465 /* The reader calls into this function to read data off the targets
468 static enum gdb_status
469 jit_target_read_impl (GDB_CORE_ADDR target_mem, void *gdb_buf, int len)
471 int result = target_read_memory ((CORE_ADDR) target_mem, gdb_buf, len);
478 /* The reader calls into this function to create a new gdb_object
479 which it can then pass around to the other callbacks. Right now,
480 all that is required is allocating the memory. */
482 static struct gdb_object *
483 jit_object_open_impl (struct gdb_symbol_callbacks *cb)
485 /* CB is not required right now, but sometime in the future we might
486 need a handle to it, and we'd like to do that without breaking
488 return XZALLOC (struct gdb_object);
491 /* Readers call into this function to open a new gdb_symtab, which,
492 again, is passed around to other callbacks. */
494 static struct gdb_symtab *
495 jit_symtab_open_impl (struct gdb_symbol_callbacks *cb,
496 struct gdb_object *object,
497 const char *file_name)
499 struct gdb_symtab *ret;
501 /* CB stays unused. See comment in jit_object_open_impl. */
503 ret = XZALLOC (struct gdb_symtab);
504 ret->file_name = file_name ? xstrdup (file_name) : xstrdup ("");
505 ret->next = object->symtabs;
506 object->symtabs = ret;
510 /* Returns true if the block corresponding to old should be placed
511 before the block corresponding to new in the final blockvector. */
514 compare_block (const struct gdb_block *const old,
515 const struct gdb_block *const new)
519 if (old->begin < new->begin)
521 else if (old->begin == new->begin)
523 if (old->end > new->end)
532 /* Called by readers to open a new gdb_block. This function also
533 inserts the new gdb_block in the correct place in the corresponding
536 static struct gdb_block *
537 jit_block_open_impl (struct gdb_symbol_callbacks *cb,
538 struct gdb_symtab *symtab, struct gdb_block *parent,
539 GDB_CORE_ADDR begin, GDB_CORE_ADDR end, const char *name)
541 struct gdb_block *block = XZALLOC (struct gdb_block);
543 block->next = symtab->blocks;
544 block->begin = (CORE_ADDR) begin;
545 block->end = (CORE_ADDR) end;
546 block->name = name ? xstrdup (name) : NULL;
547 block->parent = parent;
549 /* Ensure that the blocks are inserted in the correct (reverse of
550 the order expected by blockvector). */
551 if (compare_block (symtab->blocks, block))
553 symtab->blocks = block;
557 struct gdb_block *i = symtab->blocks;
561 /* Guaranteed to terminate, since compare_block (NULL, _)
563 if (compare_block (i->next, block))
565 block->next = i->next;
576 /* Readers call this to add a line mapping (from PC to line number) to
580 jit_symtab_line_mapping_add_impl (struct gdb_symbol_callbacks *cb,
581 struct gdb_symtab *stab, int nlines,
582 struct gdb_line_mapping *map)
589 stab->linetable = xmalloc (sizeof (struct linetable)
590 + (nlines - 1) * sizeof (struct linetable_entry));
591 stab->linetable->nitems = nlines;
592 for (i = 0; i < nlines; i++)
594 stab->linetable->item[i].pc = (CORE_ADDR) map[i].pc;
595 stab->linetable->item[i].line = map[i].line;
599 /* Called by readers to close a gdb_symtab. Does not need to do
600 anything as of now. */
603 jit_symtab_close_impl (struct gdb_symbol_callbacks *cb,
604 struct gdb_symtab *stab)
606 /* Right now nothing needs to be done here. We may need to do some
607 cleanup here in the future (again, without breaking the plugin
611 /* Transform STAB to a proper symtab, and add it it OBJFILE. */
614 finalize_symtab (struct gdb_symtab *stab, struct objfile *objfile)
616 struct symtab *symtab;
617 struct gdb_block *gdb_block_iter, *gdb_block_iter_tmp;
618 struct block *block_iter;
619 int actual_nblocks, i, blockvector_size;
620 CORE_ADDR begin, end;
622 actual_nblocks = FIRST_LOCAL_BLOCK + stab->nblocks;
624 symtab = allocate_symtab (stab->file_name, objfile);
625 /* JIT compilers compile in memory. */
626 symtab->dirname = NULL;
628 /* Copy over the linetable entry if one was provided. */
631 int size = ((stab->linetable->nitems - 1)
632 * sizeof (struct linetable_entry)
633 + sizeof (struct linetable));
634 LINETABLE (symtab) = obstack_alloc (&objfile->objfile_obstack, size);
635 memcpy (LINETABLE (symtab), stab->linetable, size);
639 LINETABLE (symtab) = NULL;
642 blockvector_size = (sizeof (struct blockvector)
643 + (actual_nblocks - 1) * sizeof (struct block *));
644 symtab->blockvector = obstack_alloc (&objfile->objfile_obstack,
647 /* (begin, end) will contain the PC range this entire blockvector
650 BLOCKVECTOR_MAP (symtab->blockvector) = NULL;
651 begin = stab->blocks->begin;
652 end = stab->blocks->end;
653 BLOCKVECTOR_NBLOCKS (symtab->blockvector) = actual_nblocks;
655 /* First run over all the gdb_block objects, creating a real block
656 object for each. Simultaneously, keep setting the real_block
658 for (i = (actual_nblocks - 1), gdb_block_iter = stab->blocks;
659 i >= FIRST_LOCAL_BLOCK;
660 i--, gdb_block_iter = gdb_block_iter->next)
662 struct block *new_block = allocate_block (&objfile->objfile_obstack);
663 struct symbol *block_name = obstack_alloc (&objfile->objfile_obstack,
664 sizeof (struct symbol));
666 BLOCK_DICT (new_block) = dict_create_linear (&objfile->objfile_obstack,
668 /* The address range. */
669 BLOCK_START (new_block) = (CORE_ADDR) gdb_block_iter->begin;
670 BLOCK_END (new_block) = (CORE_ADDR) gdb_block_iter->end;
673 memset (block_name, 0, sizeof (struct symbol));
674 SYMBOL_DOMAIN (block_name) = VAR_DOMAIN;
675 SYMBOL_CLASS (block_name) = LOC_BLOCK;
676 SYMBOL_SYMTAB (block_name) = symtab;
677 SYMBOL_BLOCK_VALUE (block_name) = new_block;
679 block_name->ginfo.name = obsavestring (gdb_block_iter->name,
680 strlen (gdb_block_iter->name),
681 &objfile->objfile_obstack);
683 BLOCK_FUNCTION (new_block) = block_name;
685 BLOCKVECTOR_BLOCK (symtab->blockvector, i) = new_block;
686 if (begin > BLOCK_START (new_block))
687 begin = BLOCK_START (new_block);
688 if (end < BLOCK_END (new_block))
689 end = BLOCK_END (new_block);
691 gdb_block_iter->real_block = new_block;
694 /* Now add the special blocks. */
696 for (i = 0; i < FIRST_LOCAL_BLOCK; i++)
698 struct block *new_block = allocate_block (&objfile->objfile_obstack);
699 BLOCK_DICT (new_block) = dict_create_linear (&objfile->objfile_obstack,
701 BLOCK_SUPERBLOCK (new_block) = block_iter;
702 block_iter = new_block;
704 BLOCK_START (new_block) = (CORE_ADDR) begin;
705 BLOCK_END (new_block) = (CORE_ADDR) end;
707 BLOCKVECTOR_BLOCK (symtab->blockvector, i) = new_block;
710 /* Fill up the superblock fields for the real blocks, using the
711 real_block fields populated earlier. */
712 for (gdb_block_iter = stab->blocks;
714 gdb_block_iter = gdb_block_iter->next)
716 if (gdb_block_iter->parent != NULL)
717 BLOCK_SUPERBLOCK (gdb_block_iter->real_block) =
718 gdb_block_iter->parent->real_block;
722 gdb_block_iter = stab->blocks;
724 for (gdb_block_iter = stab->blocks, gdb_block_iter_tmp = gdb_block_iter->next;
726 gdb_block_iter = gdb_block_iter_tmp)
728 xfree ((void *) gdb_block_iter->name);
729 xfree (gdb_block_iter);
731 xfree (stab->linetable);
732 xfree ((char *) stab->file_name);
736 /* Called when closing a gdb_objfile. Converts OBJ to a proper
740 jit_object_close_impl (struct gdb_symbol_callbacks *cb,
741 struct gdb_object *obj)
743 struct gdb_symtab *i, *j;
744 struct objfile *objfile;
745 jit_dbg_reader_data *priv_data;
747 priv_data = cb->priv_data;
749 objfile = allocate_objfile (NULL, 0);
750 objfile->gdbarch = target_gdbarch;
752 terminate_minimal_symbol_table (objfile);
754 xfree (objfile->name);
755 objfile->name = xstrdup ("<< JIT compiled code >>");
758 for (i = obj->symtabs; i; i = j)
761 finalize_symtab (i, objfile);
763 add_objfile_entry (objfile, *priv_data);
767 /* Try to read CODE_ENTRY using the loaded jit reader (if any).
768 ENTRY_ADDR is the address of the struct jit_code_entry in the
769 inferior address space. */
772 jit_reader_try_read_symtab (struct jit_code_entry *code_entry,
773 CORE_ADDR entry_addr)
777 struct jit_dbg_reader *i;
778 jit_dbg_reader_data priv_data;
779 struct gdb_reader_funcs *funcs;
780 volatile struct gdb_exception e;
781 struct gdb_symbol_callbacks callbacks =
783 jit_object_open_impl,
784 jit_symtab_open_impl,
786 jit_symtab_close_impl,
787 jit_object_close_impl,
789 jit_symtab_line_mapping_add_impl,
790 jit_target_read_impl,
795 priv_data = entry_addr;
797 if (!loaded_jit_reader)
800 gdb_mem = xmalloc (code_entry->symfile_size);
803 TRY_CATCH (e, RETURN_MASK_ALL)
804 if (target_read_memory (code_entry->symfile_addr, gdb_mem,
805 code_entry->symfile_size))
812 funcs = loaded_jit_reader->functions;
813 if (funcs->read (funcs, &callbacks, gdb_mem, code_entry->symfile_size)
819 if (jit_debug && status == 0)
820 fprintf_unfiltered (gdb_stdlog,
821 "Could not read symtab using the loaded JIT reader.\n");
825 /* Try to read CODE_ENTRY using BFD. ENTRY_ADDR is the address of the
826 struct jit_code_entry in the inferior address space. */
829 jit_bfd_try_read_symtab (struct jit_code_entry *code_entry,
830 CORE_ADDR entry_addr,
831 struct gdbarch *gdbarch)
834 struct section_addr_info *sai;
835 struct bfd_section *sec;
836 struct objfile *objfile;
837 struct cleanup *old_cleanups;
839 const struct bfd_arch_info *b;
842 fprintf_unfiltered (gdb_stdlog,
843 "jit_register_code, symfile_addr = %s, "
844 "symfile_size = %s\n",
845 paddress (gdbarch, code_entry->symfile_addr),
846 pulongest (code_entry->symfile_size));
848 nbfd = bfd_open_from_target_memory (code_entry->symfile_addr,
849 code_entry->symfile_size, gnutarget);
852 puts_unfiltered (_("Error opening JITed symbol file, ignoring it.\n"));
856 /* Check the format. NOTE: This initializes important data that GDB uses!
857 We would segfault later without this line. */
858 if (!bfd_check_format (nbfd, bfd_object))
860 printf_unfiltered (_("\
861 JITed symbol file is not an object file, ignoring it.\n"));
866 /* Check bfd arch. */
867 b = gdbarch_bfd_arch_info (gdbarch);
868 if (b->compatible (b, bfd_get_arch_info (nbfd)) != b)
869 warning (_("JITed object file architecture %s is not compatible "
870 "with target architecture %s."), bfd_get_arch_info
871 (nbfd)->printable_name, b->printable_name);
873 /* Read the section address information out of the symbol file. Since the
874 file is generated by the JIT at runtime, it should all of the absolute
875 addresses that we care about. */
876 sai = alloc_section_addr_info (bfd_count_sections (nbfd));
877 old_cleanups = make_cleanup_free_section_addr_info (sai);
879 for (sec = nbfd->sections; sec != NULL; sec = sec->next)
880 if ((bfd_get_section_flags (nbfd, sec) & (SEC_ALLOC|SEC_LOAD)) != 0)
882 /* We assume that these virtual addresses are absolute, and do not
883 treat them as offsets. */
884 sai->other[i].addr = bfd_get_section_vma (nbfd, sec);
885 sai->other[i].name = xstrdup (bfd_get_section_name (nbfd, sec));
886 sai->other[i].sectindex = sec->index;
890 /* This call takes ownership of NBFD. It does not take ownership of SAI. */
891 objfile = symbol_file_add_from_bfd (nbfd, 0, sai, OBJF_SHARED, NULL);
893 do_cleanups (old_cleanups);
894 add_objfile_entry (objfile, entry_addr);
897 /* This function registers code associated with a JIT code entry. It uses the
898 pointer and size pair in the entry to read the symbol file from the remote
899 and then calls symbol_file_add_from_local_memory to add it as though it were
900 a symbol file added by the user. */
903 jit_register_code (struct gdbarch *gdbarch,
904 CORE_ADDR entry_addr, struct jit_code_entry *code_entry)
907 const struct bfd_arch_info *b;
908 struct jit_inferior_data *inf_data = get_jit_inferior_data ();
911 fprintf_unfiltered (gdb_stdlog,
912 "jit_register_code, symfile_addr = %s, "
913 "symfile_size = %s\n",
914 paddress (gdbarch, code_entry->symfile_addr),
915 pulongest (code_entry->symfile_size));
917 success = jit_reader_try_read_symtab (code_entry, entry_addr);
920 jit_bfd_try_read_symtab (code_entry, entry_addr, gdbarch);
923 /* This function unregisters JITed code and frees the corresponding
927 jit_unregister_code (struct objfile *objfile)
929 free_objfile (objfile);
932 /* Look up the objfile with this code entry address. */
934 static struct objfile *
935 jit_find_objf_with_entry_addr (CORE_ADDR entry_addr)
937 struct objfile *objf;
938 CORE_ADDR *objf_entry_addr;
942 struct jit_objfile_data *objf_data;
944 objf_data = objfile_data (objf, jit_objfile_data);
945 if (objf_data != NULL && objf_data->addr == entry_addr)
951 /* (Re-)Initialize the jit breakpoint if necessary.
952 Return 0 on success. */
955 jit_breakpoint_re_set_internal (struct gdbarch *gdbarch,
956 struct jit_inferior_data *inf_data)
958 struct minimal_symbol *reg_symbol, *desc_symbol;
959 struct objfile *objf;
960 struct jit_objfile_data *objf_data;
962 if (inf_data->objfile != NULL)
965 /* Lookup the registration symbol. If it is missing, then we assume
966 we are not attached to a JIT. */
967 reg_symbol = lookup_minimal_symbol_and_objfile (jit_break_name, &objf);
968 if (reg_symbol == NULL || SYMBOL_VALUE_ADDRESS (reg_symbol) == 0)
971 desc_symbol = lookup_minimal_symbol (jit_descriptor_name, NULL, objf);
972 if (desc_symbol == NULL || SYMBOL_VALUE_ADDRESS (desc_symbol) == 0)
975 objf_data = get_jit_objfile_data (objf);
976 objf_data->register_code = reg_symbol;
977 objf_data->descriptor = desc_symbol;
979 inf_data->objfile = objf;
981 jit_inferior_init (gdbarch);
984 fprintf_unfiltered (gdb_stdlog,
985 "jit_breakpoint_re_set_internal, "
986 "breakpoint_addr = %s\n",
987 paddress (gdbarch, SYMBOL_VALUE_ADDRESS (reg_symbol)));
989 /* Put a breakpoint in the registration symbol. */
990 create_jit_event_breakpoint (gdbarch, SYMBOL_VALUE_ADDRESS (reg_symbol));
995 /* The private data passed around in the frame unwind callback
998 struct jit_unwind_private
1000 /* Cached register values. See jit_frame_sniffer to see how this
1002 struct gdb_reg_value **registers;
1004 /* The frame being unwound. */
1005 struct frame_info *this_frame;
1008 /* Sets the value of a particular register in this frame. */
1011 jit_unwind_reg_set_impl (struct gdb_unwind_callbacks *cb, int dwarf_regnum,
1012 struct gdb_reg_value *value)
1014 struct jit_unwind_private *priv;
1017 priv = cb->priv_data;
1019 gdb_reg = gdbarch_dwarf2_reg_to_regnum (get_frame_arch (priv->this_frame),
1024 fprintf_unfiltered (gdb_stdlog,
1025 _("Could not recognize DWARF regnum %d"),
1030 gdb_assert (priv->registers);
1031 priv->registers[gdb_reg] = value;
1035 reg_value_free_impl (struct gdb_reg_value *value)
1040 /* Get the value of register REGNUM in the previous frame. */
1042 static struct gdb_reg_value *
1043 jit_unwind_reg_get_impl (struct gdb_unwind_callbacks *cb, int regnum)
1045 struct jit_unwind_private *priv;
1046 struct gdb_reg_value *value;
1048 struct gdbarch *frame_arch;
1050 priv = cb->priv_data;
1051 frame_arch = get_frame_arch (priv->this_frame);
1053 gdb_reg = gdbarch_dwarf2_reg_to_regnum (frame_arch, regnum);
1054 size = register_size (frame_arch, gdb_reg);
1055 value = xmalloc (sizeof (struct gdb_reg_value) + size - 1);
1056 value->defined = frame_register_read (priv->this_frame, gdb_reg,
1059 value->free = reg_value_free_impl;
1063 /* gdb_reg_value has a free function, which must be called on each
1064 saved register value. */
1067 jit_dealloc_cache (struct frame_info *this_frame, void *cache)
1069 struct jit_unwind_private *priv_data = cache;
1070 struct gdbarch *frame_arch;
1073 gdb_assert (priv_data->registers);
1074 frame_arch = get_frame_arch (priv_data->this_frame);
1076 for (i = 0; i < gdbarch_num_regs (frame_arch); i++)
1077 if (priv_data->registers[i] && priv_data->registers[i]->free)
1078 priv_data->registers[i]->free (priv_data->registers[i]);
1080 xfree (priv_data->registers);
1084 /* The frame sniffer for the pseudo unwinder.
1086 While this is nominally a frame sniffer, in the case where the JIT
1087 reader actually recognizes the frame, it does a lot more work -- it
1088 unwinds the frame and saves the corresponding register values in
1089 the cache. jit_frame_prev_register simply returns the saved
1093 jit_frame_sniffer (const struct frame_unwind *self,
1094 struct frame_info *this_frame, void **cache)
1096 struct jit_inferior_data *inf_data;
1097 struct jit_unwind_private *priv_data;
1098 struct jit_dbg_reader *iter;
1099 struct gdb_unwind_callbacks callbacks;
1100 struct gdb_reader_funcs *funcs;
1102 inf_data = get_jit_inferior_data ();
1104 callbacks.reg_get = jit_unwind_reg_get_impl;
1105 callbacks.reg_set = jit_unwind_reg_set_impl;
1106 callbacks.target_read = jit_target_read_impl;
1108 if (loaded_jit_reader == NULL)
1111 funcs = loaded_jit_reader->functions;
1113 gdb_assert (!*cache);
1115 *cache = XZALLOC (struct jit_unwind_private);
1117 priv_data->registers =
1118 XCALLOC (gdbarch_num_regs (get_frame_arch (this_frame)),
1119 struct gdb_reg_value *);
1120 priv_data->this_frame = this_frame;
1122 callbacks.priv_data = priv_data;
1124 /* Try to coax the provided unwinder to unwind the stack */
1125 if (funcs->unwind (funcs, &callbacks) == GDB_SUCCESS)
1128 fprintf_unfiltered (gdb_stdlog, _("Successfully unwound frame using "
1133 fprintf_unfiltered (gdb_stdlog, _("Could not unwind frame using "
1136 jit_dealloc_cache (this_frame, *cache);
1143 /* The frame_id function for the pseudo unwinder. Relays the call to
1144 the loaded plugin. */
1147 jit_frame_this_id (struct frame_info *this_frame, void **cache,
1148 struct frame_id *this_id)
1150 struct jit_unwind_private private;
1151 struct gdb_frame_id frame_id;
1152 struct gdb_reader_funcs *funcs;
1153 struct gdb_unwind_callbacks callbacks;
1155 private.registers = NULL;
1156 private.this_frame = this_frame;
1158 /* We don't expect the frame_id function to set any registers, so we
1159 set reg_set to NULL. */
1160 callbacks.reg_get = jit_unwind_reg_get_impl;
1161 callbacks.reg_set = NULL;
1162 callbacks.target_read = jit_target_read_impl;
1163 callbacks.priv_data = &private;
1165 gdb_assert (loaded_jit_reader);
1166 funcs = loaded_jit_reader->functions;
1168 frame_id = funcs->get_frame_id (funcs, &callbacks);
1169 *this_id = frame_id_build (frame_id.stack_address, frame_id.code_address);
1172 /* Pseudo unwinder function. Reads the previously fetched value for
1173 the register from the cache. */
1175 static struct value *
1176 jit_frame_prev_register (struct frame_info *this_frame, void **cache, int reg)
1178 struct jit_unwind_private *priv = *cache;
1179 struct gdb_reg_value *value;
1182 return frame_unwind_got_optimized (this_frame, reg);
1184 gdb_assert (priv->registers);
1185 value = priv->registers[reg];
1186 if (value && value->defined)
1187 return frame_unwind_got_bytes (this_frame, reg, value->value);
1189 return frame_unwind_got_optimized (this_frame, reg);
1192 /* Relay everything back to the unwinder registered by the JIT debug
1195 static const struct frame_unwind jit_frame_unwind =
1198 default_frame_unwind_stop_reason,
1200 jit_frame_prev_register,
1207 /* This is the information that is stored at jit_gdbarch_data for each
1210 struct jit_gdbarch_data_type
1212 /* Has the (pseudo) unwinder been prepended? */
1213 int unwinder_registered;
1216 /* Check GDBARCH and prepend the pseudo JIT unwinder if needed. */
1219 jit_prepend_unwinder (struct gdbarch *gdbarch)
1221 struct jit_gdbarch_data_type *data;
1223 data = gdbarch_data (gdbarch, jit_gdbarch_data);
1224 if (!data->unwinder_registered)
1226 frame_unwind_prepend_unwinder (gdbarch, &jit_frame_unwind);
1227 data->unwinder_registered = 1;
1231 /* Register any already created translations. */
1234 jit_inferior_init (struct gdbarch *gdbarch)
1236 struct jit_descriptor descriptor;
1237 struct jit_code_entry cur_entry;
1238 struct jit_inferior_data *inf_data;
1239 CORE_ADDR cur_entry_addr;
1240 struct jit_objfile_data *objf_data;
1243 fprintf_unfiltered (gdb_stdlog, "jit_inferior_init\n");
1245 jit_prepend_unwinder (gdbarch);
1247 inf_data = get_jit_inferior_data ();
1248 if (jit_breakpoint_re_set_internal (gdbarch, inf_data) != 0)
1251 /* Read the descriptor so we can check the version number and load
1252 any already JITed functions. */
1253 if (!jit_read_descriptor (gdbarch, &descriptor, inf_data))
1256 /* Check that the version number agrees with that we support. */
1257 if (descriptor.version != 1)
1259 printf_unfiltered (_("Unsupported JIT protocol version %ld "
1260 "in descriptor (expected 1)\n"),
1261 (long) descriptor.version);
1265 /* If we've attached to a running program, we need to check the descriptor
1266 to register any functions that were already generated. */
1267 for (cur_entry_addr = descriptor.first_entry;
1268 cur_entry_addr != 0;
1269 cur_entry_addr = cur_entry.next_entry)
1271 jit_read_code_entry (gdbarch, cur_entry_addr, &cur_entry);
1273 /* This hook may be called many times during setup, so make sure we don't
1274 add the same symbol file twice. */
1275 if (jit_find_objf_with_entry_addr (cur_entry_addr) != NULL)
1278 jit_register_code (gdbarch, cur_entry_addr, &cur_entry);
1282 /* Exported routine to call when an inferior has been created. */
1285 jit_inferior_created_hook (void)
1287 jit_inferior_init (target_gdbarch);
1290 /* Exported routine to call to re-set the jit breakpoints,
1291 e.g. when a program is rerun. */
1294 jit_breakpoint_re_set (void)
1296 jit_breakpoint_re_set_internal (target_gdbarch,
1297 get_jit_inferior_data ());
1300 /* This function cleans up any code entries left over when the
1301 inferior exits. We get left over code when the inferior exits
1302 without unregistering its code, for example when it crashes. */
1305 jit_inferior_exit_hook (struct inferior *inf)
1307 struct objfile *objf;
1308 struct objfile *temp;
1310 ALL_OBJFILES_SAFE (objf, temp)
1312 struct jit_objfile_data *objf_data = objfile_data (objf,
1315 if (objf_data != NULL && objf_data->addr != 0)
1316 jit_unregister_code (objf);
1321 jit_event_handler (struct gdbarch *gdbarch)
1323 struct jit_descriptor descriptor;
1324 struct jit_code_entry code_entry;
1325 CORE_ADDR entry_addr;
1326 struct objfile *objf;
1328 /* Read the descriptor from remote memory. */
1329 if (!jit_read_descriptor (gdbarch, &descriptor, get_jit_inferior_data ()))
1331 entry_addr = descriptor.relevant_entry;
1333 /* Do the corresponding action. */
1334 switch (descriptor.action_flag)
1339 jit_read_code_entry (gdbarch, entry_addr, &code_entry);
1340 jit_register_code (gdbarch, entry_addr, &code_entry);
1342 case JIT_UNREGISTER:
1343 objf = jit_find_objf_with_entry_addr (entry_addr);
1345 printf_unfiltered (_("Unable to find JITed code "
1346 "entry at address: %s\n"),
1347 paddress (gdbarch, entry_addr));
1349 jit_unregister_code (objf);
1353 error (_("Unknown action_flag value in JIT descriptor!"));
1358 /* Called to free the data allocated to the jit_inferior_data slot. */
1361 free_objfile_data (struct objfile *objfile, void *data)
1363 struct jit_objfile_data *objf_data = data;
1365 if (objf_data->register_code != NULL)
1367 struct jit_inferior_data *inf_data = get_jit_inferior_data ();
1369 if (inf_data->objfile == objfile)
1370 inf_data->objfile = NULL;
1376 /* Initialize the jit_gdbarch_data slot with an instance of struct
1377 jit_gdbarch_data_type */
1380 jit_gdbarch_data_init (struct obstack *obstack)
1382 struct jit_gdbarch_data_type *data;
1384 data = obstack_alloc (obstack, sizeof (struct jit_gdbarch_data_type));
1385 data->unwinder_registered = 0;
1389 /* Provide a prototype to silence -Wmissing-prototypes. */
1391 extern void _initialize_jit (void);
1394 _initialize_jit (void)
1396 jit_reader_dir = relocate_gdb_directory (JIT_READER_DIR,
1397 JIT_READER_DIR_RELOCATABLE);
1398 add_setshow_zinteger_cmd ("jit", class_maintenance, &jit_debug,
1399 _("Set JIT debugging."),
1400 _("Show JIT debugging."),
1401 _("When non-zero, JIT debugging is enabled."),
1404 &setdebuglist, &showdebuglist);
1406 observer_attach_inferior_exit (jit_inferior_exit_hook);
1408 register_objfile_data_with_cleanup (NULL, free_objfile_data);
1410 register_inferior_data_with_cleanup (jit_inferior_data_cleanup);
1411 jit_gdbarch_data = gdbarch_data_register_pre_init (jit_gdbarch_data_init);
1412 if (is_dl_available ())
1414 add_com ("jit-reader-load", no_class, jit_reader_load_command, _("\
1415 Load FILE as debug info reader and unwinder for JIT compiled code.\n\
1416 Usage: jit-reader-load FILE\n\
1417 Try to load file FILE as a debug info reader (and unwinder) for\n\
1418 JIT compiled code. The file is loaded from " JIT_READER_DIR ",\n\
1419 relocated relative to the GDB executable if required."));
1420 add_com ("jit-reader-unload", no_class, jit_reader_unload_command, _("\
1421 Unload the currently loaded JIT debug info reader.\n\
1422 Usage: jit-reader-unload FILE\n\n\
1423 Do \"help jit-reader-load\" for info on loading debug info readers."));