From 243a925328f8e3184b2356bee497181049c0174f Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Wed, 9 Sep 2015 18:23:24 +0100 Subject: Replace "struct continuation" mechanism by something more extensible This adds an object oriented replacement for the "struct continuation" mechanism, and converts the stepping commands (step, next, stepi, nexti) and the "finish" commands to use it. It adds a new thread "class" (struct thread_fsm) that contains the necessary info and callbacks to manage the state machine of a thread's execution command. This allows getting rid of some hacks. E.g., in fetch_inferior_event and normal_stop we no longer need to know whether a thread is doing a multi-step (e.g., step N). This effectively makes the intermediate_continuations unused -- they'll be garbage collected in a separate patch. (They were never a proper abstraction, IMO. See how fetch_inferior_event needs to check step_multi before knowing whether to call INF_EXEC_CONTINUE or INF_EXEC_COMPLETE.) The target async vs !async uiout hacks in mi_on_normal_stop go away too. print_stop_event is no longer called from normal_stop. Instead it is now called from within each interpreter's normal_stop observer. This clears the path to make each interpreter print a stop event the way it sees fit. Currently we have some hacks in common code to differenciate CLI vs TUI vs MI around this area. The "finish" command's FSM class stores the return value plus that value's position in the value history, so that those can be printed to both MI and CLI's streams. This fixes the CLI "finish" command when run from MI -- it now also includes the function's return value in the CLI stream: (gdb) ~"callee3 (strarg=0x400730 \"A string argument.\") at src/gdb/testsuite/gdb.mi/basics.c:35\n" ~"35\t}\n" +~"Value returned is $1 = 0\n" *stopped,reason="function-finished",frame=...,gdb-result-var="$1",return-value="0",thread-id="1",stopped-threads="all",core="0" -FAIL: gdb.mi/mi-cli.exp: CLI finish: check CLI output +PASS: gdb.mi/mi-cli.exp: CLI finish: check CLI output gdb/ChangeLog: 2015-09-09 Pedro Alves * Makefile.in (COMMON_OBS): Add thread-fsm.o. * breakpoint.c (handle_jit_event): Print debug output. (bpstat_what): Split event callback handling to ... (bpstat_run_callbacks): ... this new function. (momentary_bkpt_print_it): No longer handle bp_finish here. * breakpoint.h (bpstat_run_callbacks): Declare. * gdbthread.h (struct thread_info) : Delete field. : New field. (thread_cancel_execution_command): Declare. * infcmd.c: Include thread-fsm.h. (struct step_command_fsm): New. (step_command_fsm_ops): New global. (new_step_command_fsm, step_command_fsm_prepare): New functions. (step_1): Adjust to use step_command_fsm_prepare and prepare_one_step. (struct step_1_continuation_args): Delete. (step_1_continuation): Delete. (step_command_fsm_should_stop): New function. (step_once): Delete. (step_command_fsm_clean_up, step_command_fsm_async_reply_reason) (prepare_one_step): New function, based on step_once. (until_next_command): Remove step_multi reference. (struct return_value_info): New. (print_return_value): Rename to ... (print_return_value_1): ... this. New struct return_value_info parameter. Adjust. (print_return_value): Reimplement as wrapper around print_return_value_1. (struct finish_command_fsm): New. (finish_command_continuation): Delete. (finish_command_fsm_ops): New global. (new_finish_command_fsm, finish_command_fsm_should_stop): New functions. (finish_command_fsm_clean_up, finish_command_fsm_return_value): New. (finish_command_continuation_free_arg): Delete. (finish_command_fsm_async_reply_reason): New. (finish_backward, finish_forward): Change symbol parameter to a finish_command_fsm. Adjust. (finish_command): Create a finish_command_fsm. Adjust. * infrun.c: Include "thread-fsm.h". (clear_proceed_status_thread): Delete the thread's FSM. (infrun_thread_stop_requested_callback): Cancel the thread's execution command. (clean_up_just_stopped_threads_fsms): New function. (fetch_inferior_event): Handle the event_thread's should_stop method saying the command isn't done yet. (process_event_stop_test): Run breakpoint callbacks here. (print_stop_event): Rename to ... (print_stop_location): ... this. (restore_current_uiout_cleanup): New function. (print_stop_event): Reimplement. (normal_stop): No longer notify the end_stepping_range observers here handle "step N" nor "finish" here. No longer call print_stop_event here. * infrun.h (struct return_value_info): Forward declare. (print_return_value): Declare. (print_stop_event): Change prototype. * thread-fsm.c: New file. * thread-fsm.h: New file. * thread.c: Include "thread-fsm.h". (thread_cancel_execution_command): New function. (clear_thread_inferior_resources): Call it. * cli/cli-interp.c (cli_on_normal_stop): New function. (cli_interpreter_init): Install cli_on_normal_stop as normal_stop observer. * mi/mi-interp.c: Include "thread-fsm.h". (restore_current_uiout_cleanup): Delete. (mi_on_normal_stop): If the thread has an FSM associated, and it finished, ask it for the async-reply-reason to print. Always call print_stop_event here, regardless of the top-level interpreter. Check bpstat_what to tell whether an asynchronous breakpoint hit triggered. * tui/tui-interp.c (tui_on_normal_stop): New function. (tui_init): Install tui_on_normal_stop as normal_stop observer. gdb/testsuite/ChangeLog: 2015-09-09 Pedro Alves * gdb.mi/mi-cli.exp: Add CLI finish tests. --- gdb/infrun.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'gdb/infrun.h') diff --git a/gdb/infrun.h b/gdb/infrun.h index c5b201fc714..33e729417c8 100644 --- a/gdb/infrun.h +++ b/gdb/infrun.h @@ -23,6 +23,7 @@ struct target_waitstatus; struct frame_info; struct address_space; +struct return_value_info; /* True if we are debugging run control. */ extern unsigned int debug_infrun; @@ -148,7 +149,18 @@ extern void print_exited_reason (struct ui_out *uiout, int exitstatus); inferior has stopped. */ extern void print_no_history_reason (struct ui_out *uiout); -extern void print_stop_event (struct target_waitstatus *ws); +/* Print the result of a function at the end of a 'finish' command. + RV points at an object representing the captured return value/type + and its position in the value history. */ + +extern void print_return_value (struct ui_out *uiout, + struct return_value_info *rv); + +/* Print current location without a level number, if we have changed + functions or hit a breakpoint. Print source line if we have one. + If the execution command captured a return value, print it. */ + +extern void print_stop_event (struct ui_out *uiout); /* Pretty print the results of target_wait, for debugging purposes. */ -- cgit v1.2.1