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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;


             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

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