[RFA/patch] handle_inferior_event() extract some code into a separate function

Joel Brobecker
2003-12-19T14:43:32Z

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[I think this patch was sort of pre-approved by Andrew, which explains
why I put "patch" in the subject, but I prefered to make sure and ask
for approval again. Hence the RFA]

Hello,

This change is related to a discussion started in the following thread:
http://sources.redhat.com/ml/gdb-patches/2003-12/msg00037.html

In particular, this implements the suggestion made by Andrew in the
following message:
http://sources.redhat.com/ml/gdb-patches/2003-12/msg00279.html

This patch implements the first part, which is to extract the code
inside the we-stepped-into-a-function if block, and move it to its
own function. It's fairly mechanical.

The next step will be to change the if condition itself to separate
out the targets where the new frame code is used from the ones where
the old one is still in use. I will send a patch as soon as this one
is reviewed.

2003-12-19 J. Brobecker <brobecker@gnat.com>

* infrun.c (handle_step_into_function): New function.
(handle_inferior_event): Extract out some code into the new
function above.

Tested on x86-linux, no regressions.

Ok to commit?

Thanks,
--
Joel

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Index: infrun.c
===================================================================
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.122
diff -u -p -r1.122 infrun.c
--- infrun.c 25 Nov 2003 16:01:36 -0000 1.122
+++ infrun.c 19 Dec 2003 14:33:05 -0000
@@ -987,6 +987,8 @@ struct execution_control_state

void init_execution_control_state (struct execution_control_state *ecs);

+static void handle_step_into_function (struct execution_control_state *ecs,
+ CORE_ADDR real_stop_pc);
void handle_inferior_event (struct execution_control_state *ecs);

static void check_sigtramp2 (struct execution_control_state *ecs);
@@ -1236,6 +1238,94 @@ pc_in_sigtramp (CORE_ADDR pc)
return PC_IN_SIGTRAMP (pc, name);
}

+/* Handle the inferior event in the cases when we just stepped
+ into a function. */
+
+static void
+handle_step_into_function (struct execution_control_state *ecs,
+ CORE_ADDR real_stop_pc)
+{
+ if ((step_over_calls == STEP_OVER_NONE)
+ || ((step_range_end == 1)
+ && in_prologue (prev_pc, ecs->stop_func_start)))
+ {
+ /* I presume that step_over_calls is only 0 when we're
+ supposed to be stepping at the assembly language level
+ ("stepi"). Just stop. */
+ /* Also, maybe we just did a "nexti" inside a prolog,
+ so we thought it was a subroutine call but it was not.
+ Stop as well. FENN */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
+ {
+ /* We're doing a "next". */
+
+ if (pc_in_sigtramp (stop_pc)
+ && frame_id_inner (step_frame_id,
+ frame_id_build (read_sp (), 0)))
+ /* We stepped out of a signal handler, and into its
+ calling trampoline. This is misdetected as a
+ subroutine call, but stepping over the signal
+ trampoline isn't such a bad idea. In order to do that,
+ we have to ignore the value in step_frame_id, since
+ that doesn't represent the frame that'll reach when we
+ return from the signal trampoline. Otherwise we'll
+ probably continue to the end of the program. */
+ step_frame_id = null_frame_id;
+
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* If we are in a function call trampoline (a stub between
+ the calling routine and the real function), locate the real
+ function. That's what tells us (a) whether we want to step
+ into it at all, and (b) what prologue we want to run to
+ the end of, if we do step into it. */
+ real_stop_pc = skip_language_trampoline (stop_pc);
+ if (real_stop_pc == 0)
+ real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
+ if (real_stop_pc != 0)
+ ecs->stop_func_start = real_stop_pc;
+
+ /* If we have line number information for the function we
+ are thinking of stepping into, step into it.
+
+ If there are several symtabs at that PC (e.g. with include
+ files), just want to know whether *any* of them have line
+ numbers. find_pc_line handles this. */
+ {
+ struct symtab_and_line tmp_sal;
+
+ tmp_sal = find_pc_line (ecs->stop_func_start, 0);
+ if (tmp_sal.line != 0)
+ {
+ step_into_function (ecs);
+ return;
+ }
+ }
+
+ /* If we have no line number and the step-stop-if-no-debug
+ is set, we stop the step so that the user has a chance to
+ switch in assembly mode. */
+ if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
+ {
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
+}

/* Given an execution control state that has been freshly filled in
by an event from the inferior, figure out what it means and take
@@ -2479,88 +2569,8 @@ process_event_stop_test:
|| ecs->stop_func_name == 0)
{
/* It's a subroutine call. */
-
- if ((step_over_calls == STEP_OVER_NONE)
- || ((step_range_end == 1)
- && in_prologue (prev_pc, ecs->stop_func_start)))
- {
- /* I presume that step_over_calls is only 0 when we're
- supposed to be stepping at the assembly language level
- ("stepi"). Just stop. */
- /* Also, maybe we just did a "nexti" inside a prolog,
- so we thought it was a subroutine call but it was not.
- Stop as well. FENN */
- stop_step = 1;
- print_stop_reason (END_STEPPING_RANGE, 0);
- stop_stepping (ecs);
- return;
- }
-
- if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
- {
- /* We're doing a "next". */
-
- if (pc_in_sigtramp (stop_pc)
- && frame_id_inner (step_frame_id,
- frame_id_build (read_sp (), 0)))
- /* We stepped out of a signal handler, and into its
- calling trampoline. This is misdetected as a
- subroutine call, but stepping over the signal
- trampoline isn't such a bad idea. In order to do that,
- we have to ignore the value in step_frame_id, since
- that doesn't represent the frame that'll reach when we
- return from the signal trampoline. Otherwise we'll
- probably continue to the end of the program. */
- step_frame_id = null_frame_id;
-
- step_over_function (ecs);
- keep_going (ecs);
- return;
- }
-
- /* If we are in a function call trampoline (a stub between
- the calling routine and the real function), locate the real
- function. That's what tells us (a) whether we want to step
- into it at all, and (b) what prologue we want to run to
- the end of, if we do step into it. */
- real_stop_pc = skip_language_trampoline (stop_pc);
- if (real_stop_pc == 0)
- real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
- if (real_stop_pc != 0)
- ecs->stop_func_start = real_stop_pc;
-
- /* If we have line number information for the function we
- are thinking of stepping into, step into it.
-
- If there are several symtabs at that PC (e.g. with include
- files), just want to know whether *any* of them have line
- numbers. find_pc_line handles this. */
- {
- struct symtab_and_line tmp_sal;
-
- tmp_sal = find_pc_line (ecs->stop_func_start, 0);
- if (tmp_sal.line != 0)
- {
- step_into_function (ecs);
- return;
- }
- }
-
- /* If we have no line number and the step-stop-if-no-debug
- is set, we stop the step so that the user has a chance to
- switch in assembly mode. */
- if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
- {
- stop_step = 1;
- print_stop_reason (END_STEPPING_RANGE, 0);
- stop_stepping (ecs);
- return;
- }
-
- step_over_function (ecs);
- keep_going (ecs);
+ handle_step_into_function (ecs, real_stop_pc);
return;
-
}

/* We've wandered out of the step range. */