diff options
| -rw-r--r-- | gdb/ChangeLog | 10 | ||||
| -rw-r--r-- | gdb/infrun.c | 124 |
2 files changed, 122 insertions, 12 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 306c7105535..9fed243a095 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -16,6 +16,16 @@ Also check for empty reply (target doesn't understand "bs" or "bc). (_initialize_remote): Add new methods to remote target vector. + Event handling interface for reverse debugging. + * infrun.c (enum inferior_stop_reason): Add NO_HISTORY reason. + (handle_inferior_event): Handle TARGET_WAITKIND_NO_HISTORY. + Handle stepping over a function call in reverse. + Handle stepping thru a line range in reverse. + Handle setting a step-resume breakpoint in reverse. + Handle stepping into a function in reverse. + Handle stepping between line ranges in reverse. + (print_stop_reason): Print reason for NO_HISTORY. + 2008-09-30 Paul Hilfinger <hilfinger@adacore.com> * ada-lang.c (ada_modulus): Correct to avoid sign problem with diff --git a/gdb/infrun.c b/gdb/infrun.c index 4b4df8fabaf..d6ea803d7b0 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -1193,11 +1193,17 @@ proceed (CORE_ADDR addr, enum target_signal siggnal, int step) if (addr == (CORE_ADDR) -1) { - if (pc == stop_pc && breakpoint_here_p (pc)) + if (pc == stop_pc && breakpoint_here_p (pc) + && target_get_execution_direction () != EXEC_REVERSE) /* There is a breakpoint at the address we will resume at, step one instruction before inserting breakpoints so that we do not stop right away (and report a second hit at this - breakpoint). */ + breakpoint). + + Note, we don't do this in reverse, because we won't + actually be executing the breakpoint insn anyway. + We'll be (un-)executing the previous instruction. */ + oneproc = 1; else if (gdbarch_single_step_through_delay_p (gdbarch) && gdbarch_single_step_through_delay (gdbarch, @@ -1426,7 +1432,9 @@ enum inferior_stop_reason /* Inferior exited. */ EXITED, /* Inferior received signal, and user asked to be notified. */ - SIGNAL_RECEIVED + SIGNAL_RECEIVED, + /* Reverse execution -- target ran out of history info. */ + NO_HISTORY }; /* The PTID we'll do a target_wait on.*/ @@ -2141,6 +2149,12 @@ handle_inferior_event (struct execution_control_state *ecs) ecs->event_thread->stop_signal = ecs->ws.value.sig; break; + case TARGET_WAITKIND_NO_HISTORY: + /* Reverse execution: target ran out of history info. */ + print_stop_reason (NO_HISTORY, 0); + stop_stepping (ecs); + return; + /* We had an event in the inferior, but we are not interested in handling it at this level. The lower layers have already done what needs to be done, if anything. @@ -2861,6 +2875,17 @@ infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n"); keep_going (ecs); return; } + if (stop_pc == ecs->stop_func_start && + target_get_execution_direction () == EXEC_REVERSE) + { + /* We are stepping over a function call in reverse, and + just hit the step-resume breakpoint at the start + address of the function. Go back to single-stepping, + which should take us back to the function call. */ + ecs->event_thread->stepping_over_breakpoint = 1; + keep_going (ecs); + return; + } break; case BPSTAT_WHAT_CHECK_SHLIBS: @@ -3026,10 +3051,25 @@ infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n"); && stop_pc < ecs->event_thread->step_range_end) { if (debug_infrun) - fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n", + fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n", paddr_nz (ecs->event_thread->step_range_start), paddr_nz (ecs->event_thread->step_range_end)); - keep_going (ecs); + + /* When stepping backward, stop at beginning of line range + (unles it's the function entry point, in which case + keep going back to the call point). */ + if (stop_pc == ecs->event_thread->step_range_start && + stop_pc != ecs->stop_func_start && + target_get_execution_direction () == EXEC_REVERSE) + { + ecs->event_thread->stop_step = 1; + print_stop_reason (END_STEPPING_RANGE, 0); + stop_stepping (ecs); + } + else + { + keep_going (ecs); + } return; } @@ -3116,10 +3156,31 @@ infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n"); if (ecs->event_thread->step_over_calls == STEP_OVER_ALL) { - /* We're doing a "next", set a breakpoint at callee's return - address (the address at which the caller will - resume). */ - insert_step_resume_breakpoint_at_caller (get_current_frame ()); + /* We're doing a "next". + + Normal (forward) execution: set a breakpoint at the + callee's return address (the address at which the caller + will resume). + + Reverse (backward) execution. set the step-resume + breakpoint at the start of the function that we just + stepped into (backwards), and continue to there. When we + get there, we'll need to single-step back to the + caller. */ + + if (target_get_execution_direction () == EXEC_REVERSE) + { + /* FIXME: I'm not sure if we've handled the frame for + recursion. */ + + struct symtab_and_line sr_sal; + init_sal (&sr_sal); + sr_sal.pc = ecs->stop_func_start; + insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); + } + else + insert_step_resume_breakpoint_at_caller (get_current_frame ()); + keep_going (ecs); return; } @@ -3176,9 +3237,22 @@ infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n"); return; } - /* Set a breakpoint at callee's return address (the address at - which the caller will resume). */ - insert_step_resume_breakpoint_at_caller (get_current_frame ()); + if (target_get_execution_direction () == EXEC_REVERSE) + { + /* Set a breakpoint at callee's start address. + From there we can step once and be back in the caller. */ + /* FIXME: I'm not sure we've handled the frame for recursion. */ + struct symtab_and_line sr_sal; + init_sal (&sr_sal); + sr_sal.pc = ecs->stop_func_start; + insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); + } + else + { + /* Set a breakpoint at callee's return address (the address + at which the caller will resume). */ + insert_step_resume_breakpoint_at_caller (get_current_frame ()); + } keep_going (ecs); return; } @@ -3344,6 +3418,28 @@ step_into_function (struct execution_control_state *ecs) ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch, ecs->stop_func_start); + if (target_get_execution_direction () == EXEC_REVERSE) + { + stop_func_sal = find_pc_line (stop_pc, 0); + + /* OK, we're just gonna keep stepping here. */ + if (stop_func_sal.pc == stop_pc) + { + /* We're there already. Just stop stepping now. */ + ecs->event_thread->stop_step = 1; + print_stop_reason (END_STEPPING_RANGE, 0); + stop_stepping (ecs); + return; + } + /* Else just reset the step range and keep going. + No step-resume breakpoint, they don't work for + epilogues, which can have multiple entry paths. */ + ecs->event_thread->step_range_start = stop_func_sal.pc; + ecs->event_thread->step_range_end = stop_func_sal.end; + keep_going (ecs); + return; + } + /* else... */ stop_func_sal = find_pc_line (ecs->stop_func_start, 0); /* Use the step_resume_break to step until the end of the prologue, even if that involves jumps (as it seems to on the vax under @@ -3712,6 +3808,10 @@ print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info) annotate_signal_string_end (); ui_out_text (uiout, ".\n"); break; + case NO_HISTORY: + /* Reverse execution: target ran out of history info. */ + ui_out_text (uiout, "\nNo more reverse-execution history.\n"); + break; default: internal_error (__FILE__, __LINE__, _("print_stop_reason: unrecognized enum value")); |