This is a straightforward replacement of the TUI's use of the
aforementioned hook with the register_changed observer. Since this was
the only user of the hook, this patch also removes the hook.
gdb/ChangeLog:
* defs.h (deprecated_register_changed_hook): Remove prototype.
* interps.c (clear_iterpreter_hooks): Remove reference to
deprecated_register_changed_hook.
* top.c (deprecated_register_changed_hook): Remove prototype.
* valops.c (value_assign): Remove reference to
deprecated_register_changed_hook.
* tui/tui-hooks.c (tui_register_changed): Add parameter "frame".
Add comment documenting the function.
(tui_register_changed_observer): Define.
(tui_install_hooks): Remove reference to
deprecated_register_changed_hook. Set
tui_register_changed_observer.
(tui_remove_hooks): Remove reference to
deprecated_register_changed_hook. Unset
tui_register_changed_observer.
When I replaced TUI's frame_changed hook to fix PR tui/13378 I assumed
that there's no reason to refresh register information following a call
to "up", "down" or "frame". This assumption was made to fix the problem
of refreshing frame information twice following a sync-execution normal
stop (once in tui_normal_stop and then in tui_before_prompt) -- the
second refresh removing any highlights made by the first.
I was wrong about that -- GDB's snapshot of register information is
per-frame, and when the frame changes, registers do too (most
prominently the %rip and %rsp registers). So e.g. GDB 7.8 would
highlight such register changes after invoking "up", "down" or "frame",
and current GDB does not.
To fix this regression, this patch adds another (sufficient) condition
for refreshing register information: in
tui_refresh_frame_and_register_information, always refresh register
information if frame information has changed. This makes register
information get refreshed following a call to "up", "down" or "frame"
while still avoiding the "double refresh" issue following a normal stop.
This condition may seem to obsolete the existing registers_too_p
parameter, but it does not: following a normal stop, it is possible that
registers may have changed while frame information had not. We could be
on the exact same PC with different register values. The new condition
would not catch such a case, but the registers_too_p condition will. So
both conditions seem necessary (and either one is sufficient).
gdb/ChangeLog:
* tui/tui-hooks.c (tui_refresh_frame_and_register_information):
Update commentary. Always refresh the registers when frame
information has changed.
* tui/tui-stack.c (tui_show_frame_info): Update commentary.
Change return type to int. Return 1 if frame information has
changed, 1 otherwise.
(tui_before_prompt): Update commentary.
* tui/tui-stack.h (tui_show_frame_info): Change return type to
int.
The select_frame hook is used by TUI to update TUI's frame and register
information following changes to the selected frame. The problem with
this hook is that it gets called after every single frame change, even
if the frame change is only temporary or internal. This is the primary
cause of flickering and slowdown when running the inferior under TUI
with conditional breakpoints set. Internal GDB events are the source of
many calls to select_frame and these internal events are triggered
frequently, especially when a few conditional breakpoints are set.
This patch removes the select_frame hook altogether and instead makes
the frame and register information get updated in two key places (using
observers): after an inferior stops, and right before displaying a
prompt. The latter hook covers the case when frame information must be
updated following a call to "up", "down" or "frame", and the former
covers the case when frame and register information must be updated
after a call to "continue", "step", etc. or after the inferior stops in
async execution mode. Together these hooks should cover all the cases
when frame information ought to be refreshed (and when the relevant
windows ought to be subsequently updated).
The print_frame_info_listing hook is also effectively obsolete now, but
it still must be set while the TUI is active because its caller
print_frame_info will otherwise assume that the CLI is active, and will
print the frame informaion accordingly. So this patch also sets the
print_frame_info_listing hook to a dummy callback, in lieu of outright
removing it yet.
Effectively, with this patch, frame/PC changes that do not immediately
precede an inferior-stop event or a prompt display event no longer cause
TUI's frame and register information to be updated.
And as a result of this change and of the previous change to
tui_show_frame_info, the TUI is much more disciplined about updating the
screen, and so the flicker as described in the PR is totally gone.
gdb/ChangeLog:
PR tui/13378
* frame.c (select_frame): Remove reference to
deprecated_selected_frame_level_changed_hook.
* frame.h (deprecated_selected_frame_level_changed_hook): Remove
declaration.
* stack.c (deprecated_selected_frame_level_changed_hook):
Likewise.
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook):
Rename to ...
(tui_refresh_frame_and_register_information): ... this. Bail
out if there is no stack. Don't update register information
unless registers_too_p is true.
(tui_print_frame_info_listing_hook): Rename to ...
(tui_dummy_print_frame_info_listing_hook): ... this.
(tui_before_prompt): New function.
(tui_normal_stop): New function.
(tui_before_prompt_observer): New observer.
(tui_normal_stop_observer): New observer.
(tui_install_hooks): Set
deprecated_print_frame_info_listing_hook to
tui_dummy_print_frame_info_listing_hook. Register
tui_before_prompt_observer to call tui_before_prompt and
tui_normal_stop_observer to call tui_normal_stop. Remove
reference to deprecated_selected_frame_level_changed_hook.
(tui_remove_hooks): Detach and unset tui_before_prompt_observer
and tui_normal_stop_observer. Remove reference to
deprecated_selected_frame_level_changed_hook.
In some cases tui_show_frame_info() may get called while the inferior's
terminal settings are still in effect. But when we call this function
we absolutely need to have our terminal settings in effect because the
function is responsible for redrawing TUI's windows following a change
in the selected frame or a change in the PC. If our terminal settings
are not in effect, the screen does not get redrawn properly, causing
temporary display artifacts (which can be fixed via ^L).
This scenario happens most prominently when stepping through a program
in TUI while a watchpoint is in effect.
Here is an example backtrace for when tui_show_frame_info() gets called
while target_terminal_is_inferior() == 1:
#1 0x00000000004988ee in tui_selected_frame_level_changed_hook (level=0)
#2 0x0000000000617b99 in select_frame (fi=0x18c9820)
#3 0x0000000000617c3f in get_selected_frame (message=message@entry=0x0)
#4 0x00000000004ce534 in update_watchpoint (b=b@entry=0x2d9a760,
reparse=reparse@entry=0)
#5 0x00000000004d625e in insert_breakpoints ()
#6 0x0000000000531cfe in keep_going (ecs=ecs@entry=0x7ffea7884ac0)
#7 0x00000000005326d7 in process_event_stop_test (ecs=ecs@entry=0x7ffea7884ac0)
#8 0x000000000053596e in handle_inferior_event_1 (ecs=0x7ffea7884ac0)
The fix is simple: call target_terminal_ours_for_output() before calling
tui_show_frame_info() in TUI's frame-changed hook, making sure to
restore the original terminal settings afterwards.
gdb/ChangeLog:
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook): Call
target_terminal_ours_for_output() before calling
tui_show_frame_info(), and restore the original terminal
settings afterwards.
This patch primarily rewrites defaulted_query() to use
gdb_readline_wrapper() to prompt the user for input, like
prompt_for_continue() does. The motivation for this rewrite is to be
able to reuse the default query hook in TUI, obviating the need for a
custom TUI query hook.
However, having TUI use the default query mechanism exposed a couple of
latent bugs in tui_redisplay_readline() related to the handling of
multi-line prompts, in particular GDB's multi-line quit prompt.
The first issue is an off-by-one error in the calculation of the height
of the prompt. The check in question should be col <= prev_col, not c <
prev_col, to properly account for the case when a prompt contains
multiple consecutive newlines. Failing to do so makes TUI have the
wrong idea of the vertical height of the prompt. This patch fixes the
column check.
The second issue is that cur_line does not get updated to reflect the
cursor position if the user's prompt cursor is at the end of the prompt
(i.e. if rl_point == rl_end). cur_line only gets updated if rl_point
lies between 0..rl_end-1 because that is the bounds of the for loop
responsible for updating cur_line. This patch changes the loop's bounds
to 0..rl_end so that cur_line always gets updated.
With these two bug fixes out of the way, the default query mechanism
works well in TUI even with multi-line prompts like GDB's quit prompt.
gdb/ChangeLog:
* utils.c (defaulted_query): Rewrite to use gdb_readline_wrapper
to prompt for input.
* tui/tui-hooks.c (tui_query_hook): Remove.
(tui_install_hooks): Don't set deprecated_query_hook.
* tui/tui-io.c (tui_redisplay_readline): Fix off-by-one error in
height calculation. Always update the command window's cur_line.
Basically the problem is that "symtab" is ambiguous.
Is it the primary symtab (where we canonically think of
blockvectors as being stored) or is it for a specific file
(where each file's line table is stored) ?
gdb_disassembly wants the symtab that contains the line table
but is instead getting the primary symtab.
gdb/ChangeLog:
PR symtab/17559
* symtab.c (find_pc_line_symtab): New function.
* symtab.h (find_pc_line_symtab): Declare.
* disasm.c (gdb_disassembly): Call find_pc_line_symtab instead of
find_pc_symtab.
* tui/tui-disasm.c (tui_set_disassem_content): Ditto.
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook): Ditto.
* tui/tui-source.c (tui_vertical_source_scroll): Ditto.
* tui/tui-win.c (make_visible_with_new_height): Ditto.
* tui/tui-winsource.c (tui_horizontal_source_scroll): Ditto.
(tui_display_main): Call find_pc_line_symtab instead of find_pc_line.
gdb/testsuite/ChangeLog:
PR symtab/17559
* gdb.base/line-symtabs.exp: New file.
* gdb.base/line-symtabs.c: New file.
* gdb.base/line-symtabs.h: New file.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook): Assume
there's always a frame. Use get_frame_pc_if_available instead of
get_frame_pc, and if there's no PC available, don't look up a
symtab.
* observer.texi (GDB Observers): New observer "new_objfile".
ChangeLog:
* observer.sh: Add "struct objfile" forward declaration.
* target.h (deprecated_target_new_objfile_hook): Remove.
* symfile.c (deprecated_target_new_objfile_hook): Remove.
(clear_symtab_users): Call observer_notify_new_objfile.
(symbol_file_add_with_addrs_or_offsets): Likewise.
* rs6000-nat.c: Include "observer.h".
(vmap_ldinfo): Call observer_notify_new_objfile.
(xcoff_relocate_core): Likewise.
* remote.c (remote_new_objfile_chain): Remove.
(remote_new_objfile): Do not call remote_new_objfile_chain.
(_initialize_remote): Use observer_attach_new_objfile.
* tui/tui-hooks.c (tui_target_new_objfile_chain): Remove.
(tui_new_objfile_hook): Do not call tui_target_new_objfile_chain.
(_initialize_tui_hooks): Use observer_attach_new_objfile.
* aix-thread.c: Include "observer.h".
(target_new_objfile_chain): Remove.
(new_objfile): Do not call target_new_objfile_chain.
(_initialize_aix_thread): Use observer_attach_new_objfile.
* hpux-thread.c: Include "observer.h"
(target_new_objfile_chain): Remove.
(hpux_thread_new_objfile): Make static. Do not call
target_new_objfile_chain.
(_initialize_hpux_thread): Use observer_attach_new_objfile.
* linux-thread-db.c: Include "observer.h".
(target_new_objfile_chain): Remove.
(thread_db_new_objfile): Do not call target_new_objfile_chain.
(_initialize_thread_db): Use observer_attach_new_objfile.
* sol-thread.c: Include "observer.h".
(target_new_objfile_chain): Remove.
(sol_thread_new_objfile): Make static. Do not call
target_new_objfile_chain.
(_initialize_sol_thread): Use observer_attach_new_objfile.
* Makefile.in (aix-thread.o, hpux-thread.o, linux-thread-db.o,
rs6000-nat.o, sol-thread.o, tui-hooks.o): Add dependency on
$(observer_h).
* interps.c (clear_interpreter_hooks): Do not clear
deprecated_registers_changed_hook.
* regcache.c (registers_changed): Do not call it.
* top.c (deprecated_registers_changed_hook): Do not define it.
* mi/mi-interp.c (mi_command_loop): Do not clear it.
* tui/tui-hooks.c (tui_install_hooks): Do not install it.
(tui_remove_hooks): Do not remove it.
(tui_selected_frame_level_changed_hook): Check for negative level.
Use get_selected_frame.
(tui_registers_changed_hook): Deleted.
Patrick Palka
Joel Brobecker
Doug Evans
Joel Brobecker
Stephane Carrez
Pedro Alves
Vladimir Prus
Michael Snyder
Jan Kratochvil
Tom Tromey
Daniel Jacobowitz
Ulrich Weigand
Denis Pilat
Eli Zaretskii
Andrew Cagney
Mark Kettenis
Andreas Schwab