[binutils-gdb] Remove single-step breakpoint for GDBserver internal event

[Yao Qi <qiyao at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=e3652c8460a6247f50e24deaca1c1c1c0e2a2573

commit e3652c8460a6247f50e24deaca1c1c1c0e2a2573
Author: Yao Qi <yao.qi@linaro.org>
Date:   Thu Oct 27 16:05:06 2016 +0100

    Remove single-step breakpoint for GDBserver internal event
    
    This patch removes single-step breakpoints if the event is only
    GDBserver internal, IOW, isn't reported back to GDB.
    
    gdb/gdbserver:
    
    2016-10-27  Yao Qi  <yao.qi@linaro.org>
    
    	* linux-low.c (linux_wait_1): If single-step breakpoints are
    	inserted, remove them.

Diff:
---
 gdb/gdbserver/ChangeLog   |  5 +++++
 gdb/gdbserver/linux-low.c | 32 +++++++++++++++++++++++---------
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 1a9c4e5..d43a96a 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-27  Yao Qi  <yao.qi@linaro.org>
+
+	* linux-low.c (linux_wait_1): If single-step breakpoints are
+	inserted, remove them.
+
 2016-10-26  Pedro Alves  <palves@redhat.com>
 
 	* linux-low.c (handle_extended_wait): Link parent/child fork
diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c
index f43ce7e..a463774 100644
--- a/gdb/gdbserver/linux-low.c
+++ b/gdb/gdbserver/linux-low.c
@@ -3684,17 +3684,31 @@ linux_wait_1 (ptid_t ptid,
 	  (*the_low_target.set_pc) (regcache, event_child->stop_pc);
 	}
 
-      /* We may have finished stepping over a breakpoint.  If so,
-	 we've stopped and suspended all LWPs momentarily except the
-	 stepping one.  This is where we resume them all again.  We're
-	 going to keep waiting, so use proceed, which handles stepping
-	 over the next breakpoint.  */
-      if (debug_threads)
-	debug_printf ("proceeding all threads.\n");
-
       if (step_over_finished)
-	unsuspend_all_lwps (event_child);
+	{
+	  /* If we have finished stepping over a breakpoint, we've
+	     stopped and suspended all LWPs momentarily except the
+	     stepping one.  This is where we resume them all again.
+	     We're going to keep waiting, so use proceed, which
+	     handles stepping over the next breakpoint.  */
+	  unsuspend_all_lwps (event_child);
+	}
+      else
+	{
+	  /* Remove the single-step breakpoints if any.  Note that
+	     there isn't single-step breakpoint if we finished stepping
+	     over.  */
+	  if (can_software_single_step ()
+	      && has_single_step_breakpoints (current_thread))
+	    {
+	      stop_all_lwps (0, event_child);
+	      delete_single_step_breakpoints (current_thread);
+	      unstop_all_lwps (0, event_child);
+	    }
+	}
 
+      if (debug_threads)
+	debug_printf ("proceeding all threads.\n");
       proceed_all_lwps ();
 
       if (debug_threads)