From: Daniel Jacobowitz <drow@mvista.com>
To: gdb-patches@sources.redhat.com
Subject: PATCH: Fork event updates, part the tenth
Date: Sun, 15 Dec 2002 12:17:00 -0000 [thread overview]
Message-ID: <20021215200836.GA22182@nevyn.them.org> (raw)
Right now, there are four calls to bpstat_stop_status in infrun.c. Three of
them are for catchpoints; right now, catchpoints should not be affected by
DECR_PC_AFTER_BREAK, because they aren't breakpoints. Hopefully
DECR_PC_AFTER_BREAK will be gone from this code if anyone ever has a target
where they _are_ breakpoints.
So, since a catchpoint is not a software breakpoint, we can just pass "1"
for NOT_A_SW_BREAKPOINT. This prevents an incorrect PC decrement on
i386-linux with the upcoming fork catchpoint patches. Committed.
--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer
2002-12-15 Daniel Jacobowitz <drow@mvista.com>
* infrun.c (handle_inferior_event): Assume that catchpoints
are not affected by DECR_PC_AFTER_BREAK.
Index: infrun.c
===================================================================
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.88
diff -u -p -r1.88 infrun.c
--- infrun.c 13 Dec 2002 21:57:40 -0000 1.88
+++ infrun.c 15 Dec 2002 20:03:39 -0000
@@ -1335,17 +1335,15 @@ handle_inferior_event (struct execution_
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
+
+ /* Assume that catchpoints are not really software breakpoints. If
+ some future target implements them using software breakpoints then
+ that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
+ we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
+ bpstat_stop_status will not decrement the PC. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc, 1);
+
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
goto process_event_stop_test;
@@ -1386,17 +1384,15 @@ handle_inferior_event (struct execution_
}
stop_pc = read_pc ();
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
+
+ /* Assume that catchpoints are not really software breakpoints. If
+ some future target implements them using software breakpoints then
+ that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
+ we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
+ bpstat_stop_status will not decrement the PC. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc, 1);
+
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
goto process_event_stop_test;
@@ -1435,17 +1431,15 @@ handle_inferior_event (struct execution_
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
+
+ /* Assume that catchpoints are not really software breakpoints. If
+ some future target implements them using software breakpoints then
+ that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
+ we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
+ bpstat_stop_status will not decrement the PC. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc, 1);
+
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
goto process_event_stop_test;
next reply other threads:[~2002-12-15 20:07 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-12-15 12:17 Daniel Jacobowitz [this message]
2002-12-16 8:46 ` Andrew Cagney
2002-12-16 8:57 ` Daniel Jacobowitz
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20021215200836.GA22182@nevyn.them.org \
--to=drow@mvista.com \
--cc=gdb-patches@sources.redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox