* breakpoint.h (pc_at_non_inline_function): Declare.
* breakpoint.c (is_non_inline_function,
pc_at_non_inline_function): New functions.
* infrun.c (handle_inferior_event): Don't call skip_inline_frames
if the stop is at a location where functions cannot be inlined.
* infrun.c (disable_randomization): New global variable.
(show_disable_randomization): New function.
(set_disable_randomization): Likewise.
(_initialize_infrun): Install set/show disable-randomization
commands.
* linux-nat.c (disable_randomization): Remove.
(show_disable_randomization): Likewise.
(set_disable_randomization): Likewise.
(_initialize_linux_nat): No longer install set/show
disable-randomization commands here.
(linux_nat_supports_disable_randomization): New function.
(linux_nat_add_target): Install it.
* remote.c (PACKET_QDisableRandomization): New enum value.
(remote_protocol_packets): Support QDisableRandomization.
(_initialize_remote): Likewise.
(remote_supports_disable_randomization): New function.
(init_remote_ops): Install it.
(extended_remote_supports_disable_randomization): New function.
(init_extended_remote_ops): Install it.
(extended_remote_disable_randomization): New function.
(extended_remote_create_inferior_1): Call it.
* target.h (struct target_ops): Add to_supports_disable_randomization.
(target_supports_disable_randomization): Add prototype.
* target.c (target_supports_disable_randomization): New function.
(find_default_supports_disable_randomization): Likewise.
(init_dummy_target): Install it.
doc/
* gdb.texinfo (Starting your Program): "set disable-randomization"
is no longer Linux-specific.
(Remote Configuration): Document "set remote
disable-randomization-packet".
(General Query Packets): Document "QDisableRandomization" packet
and add it to "qSupported" list.
gdbserver/
* configure.ac: Check support for personality routine.
* configure: Regenerate.
* config.in: Likewise.
* linux-low.c: Include <sys/personality.h>.
Define ADDR_NO_RANDOMIZE if necessary.
(linux_create_inferior): Disable address space randomization when
forking inferior, if requested.
(linux_supports_disable_randomization): New function.
(linux_target_ops): Install it.
* server.h (disable_randomization): Declare.
* server.c (disable_randomization): New global variable.
(handle_general_set): Handle QDisableRandomization.
(handle_query): Likewise for qSupported.
(main): Support --disable-randomization and --no-disable-randomization
command line arguments.
* target.h (struct target_ops): Add supports_disable_randomization.
(target_supports_disable_randomization): New macro.
* infrun.c (displaced_step_fixup): Move some code ...
(displaced_step_restore): ... here. New function.
(handle_inferior_event): Cleanup displaced stepping state for both
child and parent when get forked or vforked event.
* regcache.c (get_thread_arch_aspace_regcache): New function.
get_thread_arch_regcache (): Call it.
* top.c: Include interps.h.
(execute_command): If the target can async, but the interpreter is
in sync mode, synchronously wait for the command to finish before
returning.
(execute_command_to_string): Force the interpreter to sync mode.
* infrun.c: Include interps.h.
(fetch_inferior_event): Don't restore the prompt yet if the
interpreter is in sync mode.
* interps.c (interpreter_async): New global.
* interps.h (interpreter_async): Declare.
* inf-loop.c: Include interps.h.
(inferior_event_handler): Don't print the language change or run
breakpoint commands yet if the interpreter in is sync mode.
* main.c (captured_command_loop): Flip the interpreter to async
mode.
* cli/cli-script.c: Include interps.h.
(execute_user_command, while_command, if_command): Force the
interpreter to sync mode.
* python/python.c: Include interps.h.
(python_command, execute_gdb_command): Force the interpreter to
sync mode.
* breakpoint.c (bpstat_do_actions): New variable cleanup_if_error, call
make_bpstat_clear_actions_cleanup and discard_cleanups for it.
* defs.h (make_bpstat_clear_actions_cleanup): New declaration.
* exceptions.c (throw_exception): Remove the bpstat_clear_actions call.
* inf-loop.c (inferior_event_handler): New variable cleanup_if_error,
call make_bpstat_clear_actions_cleanup and discard_cleanups for it.
Call bpstat_clear_actions for failed fetch_inferior_event_wrapper.
* infrun.c (fetch_inferior_event): Call
make_bpstat_clear_actions_cleanup.
* top.c (execute_command): New variable cleanup_if_error, call
make_bpstat_clear_actions_cleanup and discard_cleanups for it.
* utils.c (do_bpstat_clear_actions_cleanup)
(make_bpstat_clear_actions_cleanup): New functions.
gdb/testsuite/
* gdb.base/commands.exp (error_clears_commands_left): New function.
(): Call it.
* infrun.c (struct execution_control_state): New member
stop_func_filled_in.
(clear_stop_func, fill_in_stop_func): New functions.
(handle_inferior_event): Call clear_stop_func rather than
manipulating the execution control state directly.
Call fill_in_stop_func lazily as required rather than
directly calling find_pc_partial_function in all cases.
gdb/
* continuations.h (continuation_ftype): Add `err' parameter.
Document parameters.
(do_all_continuations, do_all_continuations_thread)
(do_all_intermediate_continuations)
(do_all_intermediate_continuations_thread)
(do_all_inferior_continuations): Add `err' parameter.
* continuations.c (do_my_continuations_1, do_my_continuations)
(do_all_inferior_continuations, do_all_continuations_ptid)
(do_all_continuations_thread_callback)
(do_all_continuations_thread, do_all_continuations)
(do_all_intermediate_continuations_thread_callback)
(do_all_intermediate_continuations_thread)
(do_all_intermediate_continuations): Add `err' parameter, and pass
it down all the way to the continuations proper.
* inf-loop.c (inferior_event_handler): If fetching an inferior
event throws an error, don't pop the target, and still call the
continuations, but with `err' set. Adjust all other continuation
calls.
* breakpoint.c (until_break_command_continuation): Add `err'
parameter.
* infcmd.c (step_1_continuation): Add `err' parameter. Don't
issue another step if `err' is set.
(struct until_next_continuation_args): New.
(until_next_continuation): Add `err' parameter. Adjust.
(until_next_command): Adjust.
(struct finish_command_continuation_args): Add `thread' field.
(finish_command_continuation): Add `err' parameter. Handle it.
(finish_forward): Adjust.
(attach_command_continuation): Add `err' parameter. Handle it.
* infrun.c (infrun_thread_stop_requested_callback): Adjust to
cancel the continuations.
* interps.c (interp_set): Adjust to cancel the continuations.
* thread.c (clear_thread_inferior_resources): Adjust to cancel the
continuations rather than discarding.
(free_thread): Don't clear thread inferior resources here.
(delete_thread_1): Do it here instead. And do it before removing
the thread from the threads list. Tag the thread as exited before
clearing thread inferior resources.
gdb/
* record.c: Include event-loop.h, inf-loop.h.
(record_beneath_to_async): New global.
(tmp_to_async): New global.
(record_async_inferior_event_token): New global.
(record_open_1): Don't error out if async is enabled.
(record_open): Handle to_async. Create an async event source in
the event loop.
(record_close): Delete the async event source.
(record_resumed): New global.
(record_execution_dir): New global.
(record_resume, record_core_resume): Set them. Register the
target on the event loop.
(record_wait): Rename to ...
(record_wait_1): ... this. Add more debug output. Handle
TARGET_WNOHANG, and the target beneath returning
TARGET_WAITKIND_IGNORE.
(record_wait): Reimplement on top of record_wait_1.
(record_async_mask_value): New global.
(record_async, record_async_mask, record_can_async_p)
(record_is_async_p, record_execution_direction): New functions.
(init_record_ops, init_record_core_ops): Install new methods.
* infrun.c (fetch_inferior_event): Temporarily switch the global
execution direction to the direction the target was going.
(execution_direction): Change type to int.
* target.c (default_execution_direction): New function.
(update_current_target): Inherit and de_fault
to_execution_direction.
* target.h (struct target_ops) <to_execution_direction>: New
field.
(target_execution_direction): New macro.
* inferior.h (execution_direction): Change type to int.
gdb/
* infcmd.c (finish_backward): Set a step-resume breakpoint at the
function's entry point instead of a manually managed momentary
breakpoint, and only ever issue one proceed call.
* infrun.c (handle_inferior_event) <BPSTAT_WHAT_STEP_RESUME>: If
doing a reverse-finish, switch to stepi mode, to do another step.
(insert_step_resume_breakpoint_at_sal): Make public.
(normal_stop): No need to save function value return registers if
going reverse.
* inferior.h (insert_step_resume_breakpoint_at_sal): Declare.
gdb/testsuite/
* gdb.reverse/finish-reverse-bkpt.exp: New test.
gdb/
* infcmd.c: Include "inf-loop.h".
(step_once): When stepping into an inline subroutine, pretend the
target has run. If the target can async, switch the inferior
event loop to INF_EXEC_COMPLETE.
* inferior.h (user_visible_resume_ptid): Declare.
* infrun.c (user_visible_resume_ptid): New function, factored out
from `resume'.
(resume): Use it.
* mi/mi-main.c (mi_execute_async_cli_command): Remove assertion
that the current thread is running. Merge async and sync
branches.
gdb/
* infrun.c (resume): Mention which is the current thread, and its
current PC in debug output.
(prepare_to_proceed): Mention the thread switching in debug
output.
* infrun.c (proceed): Revert previous change.
(resume): Instead, handle the case of signal delivery while stepping
off a breakpoint location here, and only if software single-stepping
is used. Handle nested signals.
gdb/testsuite/
* gdb.base/signest.exp: New file.
* gdb.base/signest.c: Likewise.
* infrun.c (proceed): Do not single-step into signal delivery
when stepping off a breakpoint location.
(insert_step_resume_breakpoint_at_frame): Move prototype earlier.
(insert_step_resume_breakpoint_at_caller): Likewise.
(insert_step_resume_breakpoint_at_sal): Likewise.
(insert_longjmp_resume_breakpoint): Likewise.
testsuite/ChangeLog:
* gdb.base/annota1.exp: Accept breakpoints-invalid annotation
while delivering signal.
add to_pass_signals.
(target_notice_signals): Remove.
(target_pass_signals): Add prototype.
* target.c (update_current_target): Remove to_notice_signals;
mention to_pass_signals.
(target_pass_signals): New function.
(debug_to_notice_signals): Remove.
(setup_target_debug): Do not install debug_to_notice_signals.
* infrun.c (signal_pass): New global.
(resume): Call target_pass_signals.
(handle_inferior_event): Report all signals while stepping over
non-steppable watchpoint. Reset trap_expected to ensure breakpoints
are re-inserted when stepping over a signal handler.
(signal_cache_update): New function.
(signal_stop_update): Call it.
(signal_print_update): Likewise.
(signal_pass_update): Likewise.
(handle_command): Call signal_cache_update and target_pass_signals
instead of target_notice_signals.
(_initialize_infrun): Initialize signal_pass.
* linux-nat.c (pass_mask): New global.
(linux_nat_pass_signals): New function.
(linux_nat_create_inferior): Report all signals initially.
(linux_nat_attach): Likewise.
(linux_nat_resume): Use pass_mask to decide whether to directly
handle an inferior signal.
(linux_nat_wait_1): Likewise.
(linux_nat_add_target): Install to_pass_signals callback.
* nto-procfs.c (notice_signals): Remove.
(procfs_resume): Do not call notice_signals.
(procfs_notice_signals): Remove.
(procfs_pass_signals): New function.
(init_procfs_ops): Install to_pass_signals callback instead of
to_notice_signals callback.
(_initialize_procfs): Report all signals initially.
* procfs.c (procfs_notice_signals): Remove.
(procfs_pass_signals): New function.
(procfs_target): Install to_pass_signals callback instead of
to_notice_signals callback.
(register_gdb_signals): Remove.
(procfs_debug_inferior): Report all signals initially.
(procfs_init_inferior): Remove redundant register_gdb_signals call.
* remote.c (remote_pass_signals): Add numsigs and pass_signals
parameters; use them instead of calling signal_..._state routines.
(remote_notice_signals): Remove.
(remote_start_remote): Report all signals initially.
(remote_resume): Do not call remote_pass_signals.
(_initialize_remote): Install to_pass_signals callback instead of
to_notice_signals callback.
gdb/
* regcache.c (get_thread_arch_regcache): If creating a regcache for
null_ptid, assume and allow a NULL address space, instead of
asking the target for the ptid's address space.
* infrun.c (ptid_is_pid): Remove assertion.
gdb/testsuite/
* gdb.base/maint.exp: Test that "maint print registers" works
without a running program.
* target.c (target_read_live_memory): New function.
(memory_xfer_live_readonly_partial): New.
(memory_xfer_partial): If reading from a traceframe, fallback to
reading unavailable read-only memory from read-only regions of
live target memory.
* tracepoint.c (disconnect_tracing): Adjust.
(set_current_traceframe): New, factored out from
set_traceframe_number.
(set_traceframe_number): Reimplement to only change the traceframe
number on the GDB side.
(do_restore_current_traceframe_cleanup): Adjust.
(make_cleanup_restore_traceframe_number): New.
(cur_traceframe_number): New global.
(tfile_open): Set cur_traceframe_number to no traceframe.
(set_tfile_traceframe): New function.
(tfile_trace_find): If looking up a traceframe using any method
other than by number, make sure the current tfile traceframe
matches gdb's current traceframe. Update the current tfile
traceframe if the lookup succeeded.
(tfile_fetch_registers, tfile_xfer_partial)
(tfile_get_trace_state_variable_value): Make sure the remote
traceframe matches gdb's current traceframe.
* remote.c (remote_traceframe_number): New global.
(remote_open_1): Set it to -1.
(set_remote_traceframe): New function.
(remote_fetch_registers, remote_store_registers)
(remote_xfer_memory, remote_xfer_partial)
(remote_get_trace_state_variable_value): Make sure the remote
traceframe matches gdb's current traceframe.
(remote_trace_find): If looking up a traceframe using any method
other than by number, make sure the current remote traceframe
matches gdb's current traceframe. Update the current remote
traceframe if the lookup succeeded.
* infrun.c (fetch_inferior_event): Adjust.
* tracepoint.h (set_current_traceframe): Declare.
(get_traceframe_number, set_traceframe_number): Add describing
comments.
This signal does not indicate an error condition, so the default
behavior when receiving this signal should be to resume execution
silently.
gdb/ChangeLog:
Do not stop on SIGPRIO signals by default
* infrun.c (_initialize_infrun): Unset signal_stop and
signal_print for TARGET_SIGNAL_PRIO.
Fix step_resume_breakpoint unsaved during an infcall.
* gdbthread.h (struct thread_control_state): Move here field
step_resume_breakpoint ...
(struct thread_info): ... from here.
* infrun.c (save_infcall_control_state): Reset
control.step_resume_breakpoint to NULL.
(restore_infcall_control_state, discard_infcall_control_state): Delete
control.step_resume_breakpoint.
* arm-linux-tdep.c, infrun.c, thread.c: Update all the references to
the moved field.
gdb/testsuite/
Fix step_resume_breakpoint unsaved during an infcall.
* gdb.base/step-resume-infcall.exp: New file.
* gdb.base/step-resume-infcall.c: New file.
Rename and move inferior_thread_state and inferior_status.
* gdbthread.h (struct thread_control_state): New struct, move fields
step_range_start, step_range_end, step_frame_id, step_stack_frame_id,
trap_expected, proceed_to_finish, in_infcall, step_over_calls,
stop_step and stop_bpstat here from struct thread_info.
(struct thread_suspend_state): New struct, move field stop_signal here
from struct thread_info.
(struct thread_info): Move the fields above from this struct.
* inferior.h: Move the inferior_thread_state and inferior_status
declarations comment to their definitions at infrun.c.
(struct inferior_control_state): New struct, move field stop_soon from
struct inferior here.
(struct inferior_suspend_state): New empty struct.
(struct inferior): New fields control and suspend. Move out field
stop_soon.
* infrun.c (struct inferior_thread_state): Rename to ...
(infcall_suspend_state): ... here. Replace field stop_signal by
fields thread_suspend and inferior_suspend.
(save_inferior_thread_state): Rename to ...
(save_infcall_suspend_state): ... here. New variable inf. Update the
code for new fields.
(restore_inferior_thread_state): Rename to ...
(restore_infcall_suspend_state): ... here. New variable inf. Update
the code for new fields.
(do_restore_inferior_thread_state_cleanup): Rename to ...
(do_restore_infcall_suspend_state_cleanup): ... here.
(make_cleanup_restore_inferior_thread_state): Rename to ...
(make_cleanup_restore_infcall_suspend_state): ... here.
(discard_inferior_thread_state): Rename to ...
(discard_infcall_suspend_state): ... here.
(get_inferior_thread_state_regcache): Rename to ...
(get_infcall_suspend_state_regcache): ... here.
(struct inferior_status): Rename to ...
(struct infcall_control_state): ... here. Replace fields
step_range_start, step_range_end, step_frame_id, step_stack_frame_id,
trap_expected, proceed_to_finish, in_infcall, step_over_calls,
stop_step, stop_bpstat and stop_soon by fields thread_control and
inferior_control.
(save_inferior_status): Rename to ...
(save_infcall_control_state): ... here. Update the code for new
fields.
(restore_inferior_status): Rename to ...
(restore_infcall_control_state): ... here. Update the code for new
fields.
(do_restore_inferior_status_cleanup): Rename to ...
(do_restore_infcall_control_state_cleanup): ... here.
(make_cleanup_restore_inferior_status): Rename to ...
(make_cleanup_restore_infcall_control_state): ... here.
(discard_inferior_status): Rename to ...
(discard_infcall_control_state): ... here.
* alpha-tdep.c, breakpoint.c, dummy-frame.c, dummy-frame.h,
exceptions.c, fbsd-nat.c, gdbthread.h, infcall.c, infcmd.c,
inferior.c, inferior.h, infrun.c, linux-nat.c, mi/mi-interp.c,
mips-tdep.c, procfs.c, solib-irix.c, solib-osf.c, solib-spu.c,
solib-sunos.c, solib-svr4.c, thread.c, windows-nat.c: Update all the
references to the moved fields and renamed functions.
* infrun.c (restore_inferior_thread_state): Use
discard_inferior_thread_state to free the data.
(discard_inferior_thread_state): xfree also siginfo_data.
Revert:
2010-10-17 Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <pedro@codesourcery.com>
* gdbthread.h (currently_stepping): New declaration.
* infrun.c (currently_stepping): Remove the forward declaration.
(currently_stepping): Make it global.
* linux-nat.c (resume_callback) <lp->stopped && lp->status == 0>: New
variables tp and step, initialized them. Pass STEP to to_resume.
Print also possibly "PTRACE_SINGLESTEP" if STEP. Initialize LP->STEP.
* remote.c (currently_stepping_callback): New.
(remote_vcont_resume)
<ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)>:
New variable tp. Call currently_stepping_callback and step such
thread.
gdb/testsuite/
Revert:
2010-10-17 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.threads/sigstep-threads.exp: New file.
* gdb.threads/sigstep-threads.c: New file.
* infrun.c (follow_exec): Replace symbol_file_add_main by
symbol_file_add with SYMFILE_DEFER_BP_RESET, set_initial_language and
breakpoint_re_set.
* m32r-rom.c (m32r_load, m32r_upload_command): Use parameter 0 for
clear_symtab_users.
* objfiles.c (free_all_objfiles): Likewise.
* remote-m32r-sdi.c (m32r_load): Likewise.
* solib-som.c (som_solib_create_inferior_hook): Likewise.
* symfile.c (new_symfile_objfile): New comment for add_flags. Call
clear_symtab_users with ADD_FLAGS.
(reread_symbols): Use parameter 0 for clear_symtab_users.
(clear_symtab_users): New parameter add_flags. Do not call
breakpoint_re_set if SYMFILE_DEFER_BP_RESET.
(clear_symtab_users_cleanup): Use parameter 0 for clear_symtab_users.
* symtab.h (clear_symtab_users): New parameter add_flags.
gdb/testsuite/
* gdb.base/pie-execl.exp: New file.
* gdb.base/pie-execl.c: New file.
Fix lost siginfo_t for inferior calls.
* infrun.c
(struct inferior_thread_state) <siginfo_gdbarch, siginfo_data>: New.
(save_inferior_thread_state): New variables regcache, gdbarch and
siginfo_data. Initialize SIGINFO_DATA if gdbarch_get_siginfo_type_p.
Move INF_STATE allocation later, pre-clear it. Initialize REGISTERS
using REGCACHE.
(restore_inferior_thread_state): New variables regcache and gdbarch.
Restore SIGINFO_DATA for matching GDBARCH. Restore REGISTERS using
REGCACHE. Free also SIGINFO_DATA.
gdb/testsuite/
Fix lost siginfo_t for inferior calls.
* gdb.base/siginfo-infcall.exp: New file.
* gdb.base/siginfo-infcall.c: New file.
* infrun.c (handle_inferior_event): Handle presence of single-step
breakpoints for TARGET_WAITKIND_FORKED and TARGET_WAITKIND_VFORKED.
Cancel single-step breakpoints for TARGET_WAITKIND_EXITED,
TARGET_WAITKIND_SIGNALED, and TARGET_WAITKIND_EXECD.
* breakpoint.c (detach_single_step_breakpoints): New function.
(detach_breakpoints): Call it.
(cancel_single_step_breakpoints): New function.
* breakpoint.h (cancel_single_step_breakpoints): Add prototype.
* spu-tdep.c (spu_memory_remove_breakpoint): New function.
(spu_gdbarch_init): Install it.
testsuite/ChangeLog:
* gdb.cell/fork.exp: New file.
* gdb.cell/fork.c: Likewise.
* gdb.cell/fork-spu.c: Likewise.
Add per-operation permission flags.
* target.h (struct target_ops): New method to_set_permissions.
(target_set_permissions): New macro.
(target_insert_breakpoint): Change macro to function.
(target_remove_breakpoint): Ditto.
(target_stop): Ditto.
(may_write_registers): Declare.
(may_write_memory): Declare.
(may_insert_breakpoints): Declare.
(may_insert_tracepoints): Declare.
(may_insert_fast_tracepoints): Declare.
(may_stop): Declare.
* target.c (may_write_registers, may_write_registers_1): New globals.
(may_write_memory, may_write_memory_1): New globals.
(may_insert_breakpoints, may_insert_breakpoints_1): New globals.
(may_insert_tracepoints, may_insert_tracepoints_1): New globals.
(may_insert_fast_tracepoints, may_insert_fast_tracepoints_1): New
globals.
(may_stop, may_stop_1): New global.
(target_xfer_partial): Test for write permission.
(target_store_registers): Ditto.
(target_insert_breakpoint): New function.
(target_remove_breakpoint): New function.
(target_stop): New function.
(_initialize_targets): Add new set/show variables.
(set_write_memory_permission): New function.
(update_target_permissions): New function.
(set_target_permissions): New function.
(update_current_target): Default to_set_permissions.
(_initialize_targets): Use new globals and setter function.
* tracepoint.c (start_tracing): Test for permission.
* inferior.h (update_observer_mode): Declare.
* infrun.c (non_stop_1): Define earlier.
(observer_mode, observer_mode_1): New globals.
(set_observer_mode, show_observer_mode): New functions.
(update_observer_mode): New function.
(_initialize_infrun): Define "set observer" command.
* remote.c (PACKET_QAllow): New optional packet.
(remote_protocol_features): Add QAllow.
(remote_set_permissions): New function.
(remote_start_remote): Call it.
(init_remote_ops): Add it to target vector.
(_initialize_remote): Add config command for QAllow.
* gdb.texinfo (Observer Mode): New section.
(General Query Packets): Document QAllow.
* gdb.base/permissions.exp: New file.
This patches improves a couple of previous patches:
- one that introduces reset_schedlock, but failed to add a declarationl;
- one that was checked in to avoid a compilation failure due to that
missing declaration.
It also improves the declaration itself to better conform to our coding
practices. Same for the comments.
2010-05-17 Joel Brobecker <brobecker@adacore.com>
* target.h (reset_schedlock): Add declaration.
* infrun.c (reset_schedlock): Add missing void in function profile.
* target.c (target_mourn_inferior): Delete local declaration of
reset_schedlock. Style-fix in comment.
* infcall.c: White space.
* inf-child.c: White space.
* infcmd.c: White space.
* inferior.c: White space.
* inf-loop.c: White space.
* inflow.c: White space.
* inline-frame.c: White space.
* interps.c: White space.
* config/i386/nm-i386sol2.h (CANNOT_STEP_HW_WATCHPOINTS): Remove
macro definition and related comment.
* infrun.c (CANNOT_STEP_HW_WATCHPOINTS): Remove macro.
(resume): Remove code and comment related to this macro.
doc ChangeLog entry:
* gdbint.texinfo (CANNOT_STEP_HW_WATCHPOINTS): Remove explanation
of macro deleted from GDB code.
(cleanup_restore_current_traceframe): Declare.
* tracepoint.c (set_traceframe_number): New.
(struct current_traceframe_cleanup): New.
(do_restore_current_traceframe_cleanup)
(restore_current_traceframe_cleanup_dtor)
(make_cleanup_restore_current_traceframe): New.
* infrun.c: Include tracepoint.h.
(fetch_inferior_event): Switch out and in of tfind mode.
match a breakpoint.
(handle_inferior_event): Move the check for unusual breakpoint
signals earlier.
gdbserver/
* linux-low.c (get_stop_pc): Check for SIGTRAP.
(linux_wait_for_event_1): Handle SIGILL and SIGSEGV as possible
breakpoints.
never random signals.
* breakpoint.c (update_global_location_list): Always delete
immediately delete hardware watchpoint locations and other
locations whose target address isn't meaningful. Update comment
explaining the hazard of moribund locations.
event, check if the bpstat causes a stop, instead of if it
explains the signal.
* breakpoint.c (bpstat_causes_stop): New.
* breakpoint.h (bpstat_causes_stop): Declare.
the pspace doesn't allow breakpoints.
(insert_breakpoint_locations): Remove waiting_for_vfork_done
special case. Expect watchpoints that shouldn't be inserted, to
not be inserted.
* progspace.h (struct program_space) <breakpoints_not_allowed>:
New field.
* infrun.c (handle_inferior_event): Clear it.
* linux-nat.c (linux_child_follow_fork): Set it.
Stan Shebs <stan@codesourcery.com>
Add base multi-executable/process support to GDB.
gdb/
* Makefile.in (SFILES): Add progspace.c.
(COMMON_OBS): Add progspace.o.
* progspace.h: New.
* progspace.c: New.
* breakpoint.h (struct bp_target_info) <placed_address_space>: New
field.
(struct bp_location) <pspace>: New field.
(struct breakpoint) <pspace>: New field.
(bpstat_stop_status, breakpoint_here_p)
(moribund_breakpoint_here_p, breakpoint_inserted_here_p)
(regular_breakpoint_inserted_here_p)
(software_breakpoint_inserted_here_p, breakpoint_thread_match)
(set_default_breakpoint): Adjust prototypes.
(remove_breakpoints_pid, breakpoint_program_space_exit): Declare.
(insert_single_step_breakpoint, deprecated_insert_raw_breakpoint):
Adjust prototypes.
* breakpoint.c (executing_startup): Delete.
(default_breakpoint_sspace): New.
(breakpoint_restore_shadows): Skip if the address space doesn't
match.
(update_watchpoint): Record the frame's program space in the
breakpoint location.
(insert_bp_location): Record the address space in target_info.
Adjust to pass the symbol space to solib_name_from_address.
(breakpoint_program_space_exit): New.
(insert_breakpoint_locations): Switch the symbol space and thread
when inserting breakpoints. Don't insert breakpoints in a vfork
parent waiting for vfork done if we're not attached to the vfork
child.
(remove_breakpoints_pid): New.
(reattach_breakpoints): Switch to a thread of PID. Ignore
breakpoints of other symbol spaces.
(create_internal_breakpoint): Store the symbol space in the sal.
(create_longjmp_master_breakpoint): Iterate over all symbol
spaces.
(update_breakpoints_after_exec): Ignore breakpoints for other
symbol spaces.
(remove_breakpoint): Rename to ...
(remove_breakpoint_1): ... this. Pass the breakpoints symbol
space to solib_name_from_address.
(remove_breakpoint): New.
(mark_breakpoints_out): Ignore breakpoints from other symbol
spaces.
(breakpoint_init_inferior): Ditto.
(breakpoint_here_p): Add an address space argument and adjust to
use breakpoint_address_match.
(moribund_breakpoint_here_p): Ditto.
(regular_breakpoint_inserted_here_p): Ditto.
(breakpoint_inserted_here_p): Ditto.
(software_breakpoint_inserted_here_p): Ditto.
(breakpoint_thread_match): Ditto.
(bpstat_check_location): Ditto.
(bpstat_stop_status): Ditto.
(print_breakpoint_location): If there's a location to print,
switch the current symbol space.
(print_one_breakpoint_location): Add `allflag' argument.
(print_one_breakpoint): Ditto. Adjust.
(do_captured_breakpoint_query): Adjust.
(breakpoint_1): Adjust.
(breakpoint_has_pc): Also match the symbol space.
(describe_other_breakpoints): Add a symbol space argument and
adjust.
(set_default_breakpoint): Add a symbol space argument. Set
default_breakpoint_sspace.
(breakpoint_address_match): New.
(check_duplicates_for): Add an address space argument, and adjust.
(set_raw_breakpoint): Record the symbol space in the location and
in the breakpoint.
(set_longjmp_breakpoint): Skip longjmp master breakpoints from
other symbol spaces.
(remove_thread_event_breakpoints, remove_solib_event_breakpoints)
(disable_breakpoints_in_shlibs): Skip breakpoints from other
symbol spaces.
(disable_breakpoints_in_unloaded_shlib): Match symbol spaces.
(create_catchpoint): Set the symbol space in the sal.
(disable_breakpoints_before_startup): Skip breakpoints from other
symbol spaces. Set executing_startup in the current symbol space.
(enable_breakpoints_after_startup): Clear executing_startup in the
current symbol space. Skip breakpoints from other symbol spaces.
(clone_momentary_breakpoint): Also copy the symbol space.
(add_location_to_breakpoint): Set the location's symbol space.
(bp_loc_is_permanent): Switch thread and symbol space.
(create_breakpoint): Adjust.
(expand_line_sal_maybe): Expand comment to mention symbol spaces.
Switch thread and symbol space when reading memory.
(parse_breakpoint_sals): Set the symbol space in the sal.
(break_command_really): Ditto.
(skip_prologue_sal): Switch and space.
(resolve_sal_pc): Ditto.
(watch_command_1): Record the symbol space in the sal.
(create_ada_exception_breakpoint): Adjust.
(clear_command): Adjust. Match symbol spaces.
(update_global_location_list): Use breakpoint_address_match.
(breakpoint_re_set_one): Switch thread and space.
(breakpoint_re_set): Save symbol space.
(breakpoint_re_set_thread): Also reset the symbol space.
(deprecated_insert_raw_breakpoint): Add an address space argument.
Adjust.
(insert_single_step_breakpoint): Ditto.
(single_step_breakpoint_inserted_here_p): Ditto.
(clear_syscall_counts): New.
(_initialize_breakpoint): Install it as inferior_exit observer.
* exec.h: Include "progspace.h".
(exec_bfd, exec_bfd_mtime): New defines.
(exec_close): Declare.
* exec.c: Include "gdbthread.h" and "progspace.h".
(exec_bfd, exec_bfd_mtime, current_target_sections_1): Delete.
(using_exec_ops): New.
(exec_close_1): Rename to exec_close, and make public.
(exec_close): Rename to exec_close_1, and adjust all callers. Add
description. Remove target sections and close executables from
all program spaces.
(exec_file_attach): Add comment.
(add_target_sections): Check on `using_exec_ops' to check if the
target should be pushed.
(remove_target_sections): Only unpush the target if there are no
more target sections in any symbol space.
* gdbcore.h: Include "exec.h".
(exec_bfd, exec_bfd_mtime): Remove declarations.
* frame.h (get_frame_program_space, get_frame_address_space)
(frame_unwind_program_space): Declare.
* frame.c (struct frame_info) <pspace, aspace>: New fields.
(create_sentinel_frame): Add program space argument. Set the
pspace and aspace fields of the frame object.
(get_current_frame, create_new_frame): Adjust.
(get_frame_program_space): New.
(frame_unwind_program_space): New.
(get_frame_address_space): New.
* stack.c (print_frame_info): Adjust.
(print_frame): Use the frame's program space.
* gdbthread.h (any_live_thread_of_process): Declare.
* thread.c (any_live_thread_of_process): New.
(switch_to_thread): Switch the program space as well.
(restore_selected_frame): Don't warn if trying to restore frame
level 0.
* inferior.h: Include "progspace.h".
(detach_fork): Declare.
(struct inferior) <removable, aspace, pspace>
<vfork_parent, vfork_child, pending_detach>
<waiting_for_vfork_done>: New fields.
<terminal_info>: Remove field.
<data, num_data>: New fields.
(register_inferior_data, register_inferior_data_with_cleanup)
(clear_inferior_data, set_inferior_data, inferior_data): Declare.
(exit_inferior, exit_inferior_silent, exit_inferior_num_silent)
(inferior_appeared): Declare.
(find_inferior_pid): Typo.
(find_inferior_id, find_inferior_for_program_space): Declare.
(set_current_inferior, save_current_inferior, prune_inferiors)
(number_of_inferiors): Declare.
(inferior_list): Declare.
* inferior.c: Include "gdbcore.h" and "symfile.h".
(inferior_list): Make public.
(delete_inferior_1): Always delete thread silently.
(find_inferior_id): Make public.
(current_inferior_): New.
(current_inferior): Use it.
(set_current_inferior): New.
(restore_inferior): New.
(save_current_inferior): New.
(free_inferior): Free the per-inferior data.
(add_inferior_silent): Allocate per-inferior data.
Call inferior_appeared.
(delete_threads_of_inferior): New.
(delete_inferior_1): Adjust interface to take an inferior pointer.
(delete_inferior): Adjust.
(delete_inferior_silent): Adjust.
(exit_inferior_1): New.
(exit_inferior): New.
(exit_inferior_silent): New.
(exit_inferior_num_silent): New.
(detach_inferior): Adjust.
(inferior_appeared): New.
(discard_all_inferiors): Adjust.
(find_inferior_id): Make public. Assert pid is not zero.
(find_inferior_for_program_space): New.
(have_inferiors): Check if we have any inferior with pid not zero.
(have_live_inferiors): Go over all pushed targets looking for
process_stratum.
(prune_inferiors): New.
(number_of_inferiors): New.
(print_inferior): Add executable column. Print vfork parent/child
relationships.
(inferior_command): Adjust to cope with not running inferiors.
(remove_inferior_command): New.
(add_inferior_command): New.
(clone_inferior_command): New.
(struct inferior_data): New.
(struct inferior_data_registration): New.
(struct inferior_data_registry): New.
(inferior_data_registry): New.
(register_inferior_data_with_cleanup): New.
(register_inferior_data): New.
(inferior_alloc_data): New.
(inferior_free_data): New.
(clear_inferior_data): New.
(set_inferior_data): New.
(inferior_data): New.
(initialize_inferiors): New.
(_initialize_inferiors): Register "add-inferior",
"remove-inferior" and "clone-inferior" commands.
* objfiles.h: Include "progspace.h".
(struct objfile) <pspace>: New field.
(symfile_objfile, object_files): Don't declare.
(ALL_PSPACE_OBJFILES): New.
(ALL_PSPACE_OBJFILES_SAFE): New.
(ALL_OBJFILES, ALL_OBJFILES_SAFE): Adjust.
(ALL_PSPACE_SYMTABS): New.
(ALL_PRIMARY_SYMTABS): Adjust.
(ALL_PSPACE_PRIMARY_SYMTABS): New.
(ALL_PSYMTABS): Adjust.
(ALL_PSPACE_PSYMTABS): New.
* objfiles.c (object_files, symfile_objfile): Delete.
(struct objfile_sspace_info): New.
(objfiles_pspace_data): New.
(objfiles_pspace_data_cleanup): New.
(get_objfile_pspace_data): New.
(objfiles_changed_p): Delete.
(allocate_objfile): Set the objfile's program space. Adjust to
reference objfiles_changed_p in pspace data.
(free_objfile): Adjust to reference objfiles_changed_p in pspace
data.
(objfile_relocate): Ditto.
(update_section_map): Add pspace argument. Adjust to iterate over
objfiles in the passed in pspace.
(find_pc_section): Delete sections and num_sections statics.
Adjust to refer to program space's objfiles_changed_p. Adjust to
refer to sections and num_sections store in the objfile's pspace
data.
(objfiles_changed): Adjust to reference objfiles_changed_p in
pspace data.
(_initialize_objfiles): New.
* linespec.c (decode_all_digits, decode_dollar): Set the sal's
program space.
* source.c (current_source_pspace): New.
(get_current_source_symtab_and_line): Set the sal's program space.
(set_current_source_symtab_and_line): Set current_source_pspace.
(select_source_symtab): Ditto. Use ALL_OBJFILES.
(forget_cached_source_info): Iterate over all program spaces.
* symfile.c (clear_symtab_users): Adjust.
* symmisc.c (print_symbol_bcache_statistics): Iterate over all
program spaces.
(print_objfile_statistics): Ditto.
(maintenance_print_msymbols): Ditto.
(maintenance_print_objfiles): Ditto.
(maintenance_info_symtabs): Ditto.
(maintenance_info_psymtabs): Ditto.
* symtab.h (SYMTAB_PSPACE): New.
(struct symtab_and_line) <pspace>: New field.
* symtab.c (init_sal): Clear the sal's program space.
(find_pc_sect_symtab): Set the sal's program space. Switch thread
and space.
(append_expanded_sal): Add program space argument. Iterate over
all program spaces.
(expand_line_sal): Iterate over all program spaces. Switch
program space.
* target.h (enum target_waitkind) <TARGET_WAITKIND_VFORK_DONE>: New.
(struct target_ops) <to_thread_address_space>: New field.
(target_thread_address_space): Define.
* target.c (target_detach): Only remove breakpoints from the
inferior we're detaching.
(target_thread_address_space): New.
* defs.h (initialize_progspace): Declare.
* top.c (gdb_init): Call it.
* solist.h (struct so_list) <sspace>: New field.
* solib.h (struct program_space): Forward declare.
(solib_name_from_address): Adjust prototype.
* solib.c (so_list_head): Replace with a macro referencing the
program space.
(update_solib_list): Set the so's program space.
(solib_name_from_address): Add a program space argument and adjust.
* solib-svr4.c (struct svr4_info) <pid>: Delete field.
<interp_text_sect_low, interp_text_sect_high, interp_plt_sect_low>
<interp_plt_sect_high>: New fields.
(svr4_info_p, svr4_info): Delete.
(solib_svr4_sspace_data): New.
(get_svr4_info): Rewrite.
(svr4_sspace_data_cleanup): New.
(open_symbol_file_object): Adjust.
(svr4_default_sos): Adjust.
(svr4_fetch_objfile_link_map): Adjust.
(interp_text_sect_low, interp_text_sect_high, interp_plt_sect_low)
(interp_plt_sect_high): Delete.
(svr4_in_dynsym_resolve_code): Adjust.
(enable_break): Adjust.
(svr4_clear_solib): Revert bit that removed the svr4_info here,
and reinstate clearing debug_base, debug_loader_offset_p,
debug_loader_offset and debug_loader_name.
(_initialize_svr4_solib): Register solib_svr4_pspace_data. Don't
install an inferior_exit observer anymore.
* printcmd.c (struct display) <pspace>: New field.
(display_command): Set the display's sspace.
(do_one_display): Match the display's sspace.
(display_uses_solib_p): Ditto.
* linux-fork.c (detach_fork): Moved to infrun.c.
(_initialize_linux_fork): Moved "detach-on-fork" command to
infrun.c.
* infrun.c (detach_fork): Moved from linux-fork.c.
(proceed_after_vfork_done): New.
(handle_vfork_child_exec_or_exit): New.
(follow_exec_mode_replace, follow_exec_mode_keep)
(follow_exec_mode_names, follow_exec_mode_string)
(show_follow_exec_mode_string): New.
(follow_exec): New. Reinstate the mark_breakpoints_out call.
Remove shared libraries before attaching new executable. If user
wants to keep the inferior, keep it.
(displaced_step_fixup): Adjust to pass an address space to the
breakpoints module.
(resume): Ditto.
(clear_proceed_status): In all-stop mode, always clear the proceed
status of all threads.
(prepare_to_proceed): Adjust to pass an address space to the
breakpoints module.
(proceed): Ditto.
(adjust_pc_after_break): Ditto.
(handle_inferior_event): When handling a process exit, switch the
program space to the inferior's that had exited. Call
handle_vfork_child_exec_or_exit. Adjust to pass an address space
to the breakpoints module. In non-stop mode, when following a
fork and detach-fork is off, also resume the other branch. Handle
TARGET_WAITKIND_VFORK_DONE. Set the program space in sals.
(normal_stop): Prune inferiors.
(_initialize_infrun): Install the new "follow-exec-mode" command.
"detach-on-fork" moved here.
* regcache.h (get_regcache_aspace): Declare.
* regcache.c (struct regcache) <aspace>: New field.
(regcache_xmalloc): Clear the aspace.
(get_regcache_aspace): New.
(regcache_cpy): Copy the aspace field.
(regcache_cpy_no_passthrough): Ditto.
(get_thread_regcache): Fetch the thread's address space from the
target, and store it in the regcache.
* infcall.c (call_function_by_hand): Set the sal's pspace.
* arch-utils.c (default_has_shared_address_space): New.
* arch-utils.h (default_has_shared_address_space): Declare.
* gdbarch.sh (has_shared_address_space): New.
* gdbarch.h, gdbarch.c: Regenerate.
* linux-tdep.c: Include auxv.h, target.h, elf/common.h.
(linux_has_shared_address_space): New.
(_initialize_linux_tdep): Declare.
* arm-tdep.c (arm_software_single_step): Pass the frame's address
space to insert_single_step_breakpoint.
* arm-linux-tdep.c (arm_linux_software_single_step): Pass the
frame's pspace to breakpoint functions.
* cris-tdep.c (crisv32_single_step_through_delay): Ditto.
(cris_software_single_step): Ditto.
* mips-tdep.c (deal_with_atomic_sequence): Add frame argument.
Pass the frame's pspace to breakpoint functions.
(mips_software_single_step): Adjust.
(mips_single_step_through_delay): Adjust.
* rs6000-aix-tdep.c (rs6000_software_single_step): Adjust.
* rs6000-tdep.c (ppc_deal_with_atomic_sequence): Adjust.
* solib-irix.c (enable_break): Adjust to pass the current frame's
address space to breakpoint functions.
* sparc-tdep.c (sparc_software_single_step): Ditto.
* spu-tdep.c (spu_software_single_step): Ditto.
* alpha-tdep.c (alpha_software_single_step): Ditto.
* record.c (record_wait): Adjust to pass an address space to the
breakpoints module.
* fork-child.c (fork_inferior): Set the new inferior's program and
address spaces.
* inf-ptrace.c (inf_ptrace_follow_fork): Copy the parent's program
and address spaces.
(inf_ptrace_attach): Set the inferior's program and address spaces.
* linux-nat.c: Include "solib.h".
(linux_child_follow_fork): Manage parent and child's program and
address spaces. Clone the parent's program space if necessary.
Don't wait for the vfork to be done here. Refuse to resume if
following the vfork parent while leaving the child stopped.
(resume_callback): Don't resume a vfork parent.
(linux_nat_resume): Also check for pending events in the
lp->waitstatus field.
(linux_handle_extended_wait): Report TARGET_WAITKIND_VFORK_DONE
events to the core.
(stop_wait_callback): Don't wait for SIGSTOP on vfork parents.
(cancel_breakpoint): Adjust.
* linux-thread-db.c (thread_db_wait): Don't remove thread event
breakpoints here.
(thread_db_mourn_inferior): Don't mark breakpoints out here.
Remove thread event breakpoints after mourning.
* corelow.c: Include progspace.h.
(core_open): Set the inferior's program and address spaces.
* remote.c (remote_add_inferior): Set the new inferior's program
and address spaces.
(remote_start_remote): Update address spaces.
(extended_remote_create_inferior_1): Don't init the thread list if
we already debugging other inferiors.
* darwin-nat.c (darwin_attach): Set the new inferior's program and
address spaces.
* gnu-nat.c (gnu_attach): Ditto.
* go32-nat.c (go32_create_inferior): Ditto.
* inf-ttrace.c (inf_ttrace_follow_fork, inf_ttrace_attach): Ditto.
* monitor.c (monitor_open): Ditto.
* nto-procfs.c (procfs_attach, procfs_create_inferior): Ditto.
* procfs.c (do_attach): Ditto.
* windows-nat.c (do_initial_windows_stuff): Ditto.
* inflow.c (inferior_process_group)
(terminal_init_inferior_with_pgrp, terminal_inferior,
(terminal_ours_1, inflow_inferior_exit, copy_terminal_info)
(child_terminal_info, new_tty_postfork, set_sigint_trap): Adjust
to use per-inferior data instead of inferior->terminal_info.
(inflow_inferior_data): New.
(inflow_new_inferior): Delete.
(inflow_inferior_data_cleanup): New.
(get_inflow_inferior_data): New.
* mi/mi-interp.c (mi_new_inferior): Rename to...
(mi_inferior_appeared): ... this.
(mi_interpreter_init): Adjust.
* tui/tui-disasm.c: Include "progspace.h".
(tui_set_disassem_content): Pass an address space to
breakpoint_here_p.
* NEWS: Mention multi-program debugging support. Mention new
commands "add-inferior", "clone-inferior", "remove-inferior",
"maint info program-spaces", and new option "set
follow-exec-mode".
2009-10-19 Pedro Alves <pedro@codesourcery.com>
Stan Shebs <stan@codesourcery.com>
gdb/doc/
* observer.texi (new_inferior): Rename to...
(inferior_appeared): ... this.
2009-10-19 Pedro Alves <pedro@codesourcery.com>
Stan Shebs <stan@codesourcery.com>
gdb/testsuite/
* gdb.base/foll-vfork.exp: Adjust to spell out "follow-fork".
* gdb.base/foll-exec.exp: Adjust to expect a process id before
"Executing new program".
* gdb.base/foll-fork.exp: Adjust to spell out "follow-fork".
* gdb.base/multi-forks.exp: Ditto. Adjust to the inferior being
left listed after having been killed.
* gdb.base/attach.exp: Adjust to spell out "symbol-file".
* gdb.base/maint.exp: Adjust test.
* Makefile.in (ALL_SUBDIRS): Add gdb.multi.
* gdb.multi/Makefile.in: New.
* gdb.multi/base.exp: New.
* gdb.multi/goodbye.c: New.
* gdb.multi/hangout.c: New.
* gdb.multi/hello.c: New.
* gdb.multi/bkpt-multi-exec.c: New.
* gdb.multi/bkpt-multi-exec.exp: New.
* gdb.multi/crashme.c: New.
2009-10-19 Pedro Alves <pedro@codesourcery.com>
Stan Shebs <stan@codesourcery.com>
gdb/doc/
* gdb.texinfo (Inferiors): Rename node to ...
(Inferiors and Programs): ... this. Mention running multiple
programs in the same debug session.
<info inferiors>: Mention the new 'Executable' column if "info
inferiors". Update examples. Document the "add-inferior",
"clone-inferior", "remove-inferior" and "maint info
program-spaces" commands.
(Process): Rename node to...
(Forks): ... this. Document "set|show follow-exec-mode".
(SYSCALL_SIGTRAP): New.
(status_to_str): Adjust.
(get_pending_status): Pending events in lp->waitstatus don't map
to any signal. Simplify.
(linux_handle_syscall_trap): New.
(linux_handle_extended_wait): When handling PTRACE_EVENT_CLONE
events, use linux_ops->to_resume instead of direct ptrace with
PTRACE_CONT. Remove all TRAP_IS_SYSCALL handling.
(wait_lwp): Handle syscall traps with linux_handle_syscall_trap,
and clear the sysgood bit.
(status_callback): Make it clearer and add comments.
(cancel_breakpoints_callback): Ignore if LP has waitstatus set.
(linux_nat_filter_event): Handle syscall traps with
linux_handle_syscall_trap, and clear the sysgood bit. Move the
check for storing siginfo to after handling extended statuses and
syscall traps. Store status in the lwp object.
(linux_wait_1): Don't swap the pending status out of the lwp
object until after deciding we found an lwp with an interesting
event. Requeue a new pending signal if we find one while getting
rid or a pending SIGSTOP we sent ourselves. Don't clear the
sysgood bit here.
* infrun.c (deal_with_syscall_event): Rename to ...
(handle_syscall_event): ... this. Always context switch and set
stop_pc, even if not catching the syscall. If not catching the
syscall, always resume with keep_going.
(handle_inferior_event): Adjust.
* gdbarch.c, gdbarch.h: Regenerate.
* arch-utils.c (default_displaced_step_hw_singlestep): New function.
* arch-utils.h (default_displaced_step_hw_singlestep): Add prototype.
* ppc-linux-tdep.c (ppc_displaced_step_hw_singlestep): New function.
(rs6000_gdbarch_init): Install it.
* infrun.c (displaced_step_fixup): Use new callback to determine
whether to "step" or "continue" displaced copy.
(resume): Likewise. Do not call maybe_software_singlestep
for displaced stepping.
(maybe_software_singlestep): Do not handle displaced stepping.