/* Handle JIT code generation in the inferior for GDB, the GNU Debugger.
- Copyright (C) 2009, 2010 Free Software Foundation, Inc.
+ Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc.
This file is part of GDB.
#include "jit.h"
#include "breakpoint.h"
+#include "command.h"
+#include "gdbcmd.h"
#include "gdbcore.h"
+#include "inferior.h"
#include "observer.h"
#include "objfiles.h"
#include "symfile.h"
static const char *const jit_descriptor_name = "__jit_debug_descriptor";
-/* This is the address of the JIT descriptor in the inferior. */
+static const struct inferior_data *jit_inferior_data = NULL;
-static CORE_ADDR jit_descriptor_addr = 0;
+static void jit_inferior_init (struct gdbarch *gdbarch);
-/* This is a boolean indicating whether we're currently registering code. This
- is used to avoid re-entering the registration code. We want to check for
- new JITed every time a new object file is loaded, but we want to avoid
- checking for new code while we're registering object files for JITed code.
- Therefore, we flip this variable to 1 before registering new object files,
- and set it to 0 before returning. */
+/* Non-zero if we want to see trace of jit level stuff. */
-static int registering_code = 0;
-
-/* Helper cleanup function to clear an integer flag like the one above. */
+static int jit_debug = 0;
static void
-clear_int (void *int_addr)
+show_jit_debug (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
{
- *((int *) int_addr) = 0;
+ fprintf_filtered (file, _("JIT debugging is %s.\n"), value);
}
struct target_buffer
{
CORE_ADDR base;
- size_t size;
+ ULONGEST size;
};
/* Openning the file is a no-op. */
/* Open a BFD from the target's memory. */
static struct bfd *
-bfd_open_from_target_memory (CORE_ADDR addr, size_t size, char *target)
+bfd_open_from_target_memory (CORE_ADDR addr, ULONGEST size, char *target)
{
const char *filename = xstrdup ("<in-memory>");
struct target_buffer *buffer = xmalloc (sizeof (struct target_buffer));
mem_bfd_iovec_stat);
}
-/* Helper function for reading the global JIT descriptor from remote memory. */
+/* Per-inferior structure recording the addresses in the inferior. */
+
+struct jit_inferior_data
+{
+ CORE_ADDR breakpoint_addr; /* &__jit_debug_register_code() */
+ CORE_ADDR descriptor_addr; /* &__jit_debug_descriptor */
+};
+
+/* Return jit_inferior_data for current inferior. Allocate if not already
+ present. */
+
+static struct jit_inferior_data *
+get_jit_inferior_data (void)
+{
+ struct inferior *inf;
+ struct jit_inferior_data *inf_data;
+
+ inf = current_inferior ();
+ inf_data = inferior_data (inf, jit_inferior_data);
+ if (inf_data == NULL)
+ {
+ inf_data = XZALLOC (struct jit_inferior_data);
+ set_inferior_data (inf, jit_inferior_data, inf_data);
+ }
+
+ return inf_data;
+}
+
+static void
+jit_inferior_data_cleanup (struct inferior *inf, void *arg)
+{
+ xfree (arg);
+}
+
+/* Helper function for reading the global JIT descriptor from remote
+ memory. */
static void
jit_read_descriptor (struct gdbarch *gdbarch,
- struct jit_descriptor *descriptor)
+ struct jit_descriptor *descriptor,
+ CORE_ADDR descriptor_addr)
{
int err;
struct type *ptr_type;
desc_buf = alloca (desc_size);
/* Read the descriptor. */
- err = target_read_memory (jit_descriptor_addr, desc_buf, desc_size);
+ err = target_read_memory (descriptor_addr, desc_buf, desc_size);
if (err)
error (_("Unable to read JIT descriptor from remote memory!"));
jit_read_code_entry (struct gdbarch *gdbarch,
CORE_ADDR code_addr, struct jit_code_entry *code_entry)
{
- int err;
+ int err, off;
struct type *ptr_type;
int ptr_size;
int entry_size;
+ int align_bytes;
gdb_byte *entry_buf;
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
extract_typed_address (&entry_buf[ptr_size], ptr_type);
code_entry->symfile_addr =
extract_typed_address (&entry_buf[2 * ptr_size], ptr_type);
+
+ align_bytes = gdbarch_long_long_align_bit (gdbarch) / 8;
+ off = 3 * ptr_size;
+ off = (off + (align_bytes - 1)) & ~(align_bytes - 1);
+
code_entry->symfile_size =
- extract_unsigned_integer (&entry_buf[3 * ptr_size], 8, byte_order);
+ extract_unsigned_integer (&entry_buf[off], 8, byte_order);
}
/* This function registers code associated with a JIT code entry. It uses the
struct section_addr_info *sai;
struct bfd_section *sec;
struct objfile *objfile;
- struct cleanup *old_cleanups, *my_cleanups;
+ struct cleanup *old_cleanups;
int i;
const struct bfd_arch_info *b;
CORE_ADDR *entry_addr_ptr;
+ if (jit_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "jit_register_code, symfile_addr = %s, "
+ "symfile_size = %s\n",
+ paddress (gdbarch, code_entry->symfile_addr),
+ pulongest (code_entry->symfile_size));
+
nbfd = bfd_open_from_target_memory (code_entry->symfile_addr,
code_entry->symfile_size, gnutarget);
- old_cleanups = make_cleanup_bfd_close (nbfd);
+ if (nbfd == NULL)
+ {
+ puts_unfiltered (_("Error opening JITed symbol file, ignoring it.\n"));
+ return;
+ }
/* Check the format. NOTE: This initializes important data that GDB uses!
We would segfault later without this line. */
{
printf_unfiltered (_("\
JITed symbol file is not an object file, ignoring it.\n"));
- do_cleanups (old_cleanups);
+ bfd_close (nbfd);
return;
}
file is generated by the JIT at runtime, it should all of the absolute
addresses that we care about. */
sai = alloc_section_addr_info (bfd_count_sections (nbfd));
- make_cleanup_free_section_addr_info (sai);
+ old_cleanups = make_cleanup_free_section_addr_info (sai);
i = 0;
for (sec = nbfd->sections; sec != NULL; sec = sec->next)
if ((bfd_get_section_flags (nbfd, sec) & (SEC_ALLOC|SEC_LOAD)) != 0)
++i;
}
- /* Raise this flag while we register code so we won't trigger any
- re-registration. */
- registering_code = 1;
- my_cleanups = make_cleanup (clear_int, ®istering_code);
-
- /* This call takes ownership of sai. */
- objfile = symbol_file_add_from_bfd (nbfd, 0, sai, OBJF_SHARED);
-
- /* Clear the registering_code flag. */
- do_cleanups (my_cleanups);
+ /* This call takes ownership of NBFD. It does not take ownership of SAI. */
+ objfile = symbol_file_add_from_bfd (nbfd, 0, sai, OBJF_SHARED, NULL);
/* Remember a mapping from entry_addr to objfile. */
entry_addr_ptr = xmalloc (sizeof (CORE_ADDR));
*entry_addr_ptr = entry_addr;
set_objfile_data (objfile, jit_objfile_data, entry_addr_ptr);
- discard_cleanups (old_cleanups);
+ do_cleanups (old_cleanups);
}
-/* This function unregisters JITed code and frees the corresponding objfile. */
+/* This function unregisters JITed code and frees the corresponding
+ objfile. */
static void
jit_unregister_code (struct objfile *objfile)
return NULL;
}
-/* (Re-)Initialize the jit breakpoint handler, and register any already
- created translations. */
+/* (Re-)Initialize the jit breakpoint if necessary.
+ Return 0 on success. */
+
+static int
+jit_breakpoint_re_set_internal (struct gdbarch *gdbarch,
+ struct jit_inferior_data *inf_data)
+{
+ if (inf_data->breakpoint_addr == 0)
+ {
+ struct minimal_symbol *reg_symbol;
+
+ /* Lookup the registration symbol. If it is missing, then we assume
+ we are not attached to a JIT. */
+ reg_symbol = lookup_minimal_symbol (jit_break_name, NULL, NULL);
+ if (reg_symbol == NULL)
+ return 1;
+ inf_data->breakpoint_addr = SYMBOL_VALUE_ADDRESS (reg_symbol);
+ if (inf_data->breakpoint_addr == 0)
+ return 2;
+
+ /* If we have not read the jit descriptor yet (e.g. because the JITer
+ itself is in a shared library which just got loaded), do so now. */
+ if (inf_data->descriptor_addr == 0)
+ jit_inferior_init (gdbarch);
+ }
+ else
+ return 0;
+
+ if (jit_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "jit_breakpoint_re_set_internal, "
+ "breakpoint_addr = %s\n",
+ paddress (gdbarch, inf_data->breakpoint_addr));
+
+ /* Put a breakpoint in the registration symbol. */
+ create_jit_event_breakpoint (gdbarch, inf_data->breakpoint_addr);
+
+ return 0;
+}
+
+/* Register any already created translations. */
static void
jit_inferior_init (struct gdbarch *gdbarch)
{
- struct minimal_symbol *reg_symbol;
- struct minimal_symbol *desc_symbol;
- CORE_ADDR reg_addr;
struct jit_descriptor descriptor;
struct jit_code_entry cur_entry;
+ struct jit_inferior_data *inf_data;
CORE_ADDR cur_entry_addr;
- /* When we register code, GDB resets its breakpoints in case symbols have
- changed. That in turn calls this handler, which makes us look for new
- code again. To avoid being re-entered, we check this flag. */
- if (registering_code)
- return;
+ if (jit_debug)
+ fprintf_unfiltered (gdb_stdlog, "jit_inferior_init\n");
- /* Lookup the registration symbol. If it is missing, then we assume we are
- not attached to a JIT. */
- reg_symbol = lookup_minimal_symbol (jit_break_name, NULL, NULL);
- if (reg_symbol == NULL)
- return;
- reg_addr = SYMBOL_VALUE_ADDRESS (reg_symbol);
- if (reg_addr == 0)
+ inf_data = get_jit_inferior_data ();
+ if (jit_breakpoint_re_set_internal (gdbarch, inf_data) != 0)
return;
- /* Lookup the descriptor symbol and cache the addr. If it is missing, we
- assume we are not attached to a JIT and return early. */
- desc_symbol = lookup_minimal_symbol (jit_descriptor_name, NULL, NULL);
- if (desc_symbol == NULL)
- return;
- jit_descriptor_addr = SYMBOL_VALUE_ADDRESS (desc_symbol);
- if (jit_descriptor_addr == 0)
- return;
+ if (inf_data->descriptor_addr == 0)
+ {
+ struct minimal_symbol *desc_symbol;
+
+ /* Lookup the descriptor symbol and cache the addr. If it is
+ missing, we assume we are not attached to a JIT and return early. */
+ desc_symbol = lookup_minimal_symbol (jit_descriptor_name, NULL, NULL);
+ if (desc_symbol == NULL)
+ return;
- /* Read the descriptor so we can check the version number and load any already
- JITed functions. */
- jit_read_descriptor (gdbarch, &descriptor);
+ inf_data->descriptor_addr = SYMBOL_VALUE_ADDRESS (desc_symbol);
+ if (inf_data->descriptor_addr == 0)
+ return;
+ }
+
+ if (jit_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "jit_inferior_init, descriptor_addr = %s\n",
+ paddress (gdbarch, inf_data->descriptor_addr));
+
+ /* Read the descriptor so we can check the version number and load
+ any already JITed functions. */
+ jit_read_descriptor (gdbarch, &descriptor, inf_data->descriptor_addr);
/* Check that the version number agrees with that we support. */
if (descriptor.version != 1)
error (_("Unsupported JIT protocol version in descriptor!"));
- /* Put a breakpoint in the registration symbol. */
- create_jit_event_breakpoint (gdbarch, reg_addr);
-
- /* If we've attached to a running program, we need to check the descriptor to
- register any functions that were already generated. */
+ /* If we've attached to a running program, we need to check the descriptor
+ to register any functions that were already generated. */
for (cur_entry_addr = descriptor.first_entry;
cur_entry_addr != 0;
cur_entry_addr = cur_entry.next_entry)
void
jit_breakpoint_re_set (void)
{
+ jit_breakpoint_re_set_internal (target_gdbarch,
+ get_jit_inferior_data ());
+}
+
+/* Reset inferior_data, so sybols will be looked up again, and jit_breakpoint
+ will be reset. */
+
+static void
+jit_reset_inferior_data_and_breakpoints (void)
+{
+ struct jit_inferior_data *inf_data;
+
+ /* Force jit_inferior_init to re-lookup of jit symbol addresses. */
+ inf_data = get_jit_inferior_data ();
+ inf_data->breakpoint_addr = 0;
+ inf_data->descriptor_addr = 0;
+
+ /* Remove any existing JIT breakpoint(s). */
+ remove_jit_event_breakpoints ();
+
jit_inferior_init (target_gdbarch);
}
static void
jit_inferior_created_observer (struct target_ops *objfile, int from_tty)
{
- jit_inferior_init (target_gdbarch);
+ jit_reset_inferior_data_and_breakpoints ();
}
-/* This function cleans up any code entries left over when the inferior exits.
- We get left over code when the inferior exits without unregistering its code,
- for example when it crashes. */
+/* This function cleans up any code entries left over when the
+ inferior exits. We get left over code when the inferior exits
+ without unregistering its code, for example when it crashes. */
static void
jit_inferior_exit_hook (struct inferior *inf)
struct objfile *objf;
struct objfile *temp;
- /* We need to reset the descriptor addr so that next time we load up the
- inferior we look for it again. */
- jit_descriptor_addr = 0;
-
ALL_OBJFILES_SAFE (objf, temp)
if (objfile_data (objf, jit_objfile_data) != NULL)
jit_unregister_code (objf);
}
+static void
+jit_executable_changed_observer (void)
+{
+ jit_reset_inferior_data_and_breakpoints ();
+}
+
void
jit_event_handler (struct gdbarch *gdbarch)
{
struct objfile *objf;
/* Read the descriptor from remote memory. */
- jit_read_descriptor (gdbarch, &descriptor);
+ jit_read_descriptor (gdbarch, &descriptor,
+ get_jit_inferior_data ()->descriptor_addr);
entry_addr = descriptor.relevant_entry;
- /* Do the corresponding action. */
+ /* Do the corresponding action. */
switch (descriptor.action_flag)
{
case JIT_NOACTION:
case JIT_UNREGISTER:
objf = jit_find_objf_with_entry_addr (entry_addr);
if (objf == NULL)
- printf_unfiltered (_("Unable to find JITed code entry at address: %s\n"),
+ printf_unfiltered (_("Unable to find JITed code "
+ "entry at address: %s\n"),
paddress (gdbarch, entry_addr));
else
jit_unregister_code (objf);
void
_initialize_jit (void)
{
+ add_setshow_zinteger_cmd ("jit", class_maintenance, &jit_debug,
+ _("Set JIT debugging."),
+ _("Show JIT debugging."),
+ _("When non-zero, JIT debugging is enabled."),
+ NULL,
+ show_jit_debug,
+ &setdebuglist, &showdebuglist);
+
observer_attach_inferior_created (jit_inferior_created_observer);
observer_attach_inferior_exit (jit_inferior_exit_hook);
+ observer_attach_executable_changed (jit_executable_changed_observer);
jit_objfile_data = register_objfile_data ();
+ jit_inferior_data =
+ register_inferior_data_with_cleanup (jit_inferior_data_cleanup);
}