PR threads/10729

	* linux-x86-low.c (update_debug_registers_callback): New.
	(i386_dr_low_set_addr): Use it.
	(i386_dr_low_get_addr): New.
	(i386_dr_low_set_control): Use update_debug_registers_callback.
	(i386_dr_low_get_control): New.
	(i386_dr_low_get_status): Adjust.
	* linux-low.c (linux_stop_lwp): New.
	* linux-low.h (linux_stop_lwp): Declare.

	* i386-low.c (I386_DR_GET_RW_LEN): Take the dr7 contents as
	argument instead of a i386_debug_reg_state.
	(I386_DR_WATCH_HIT): Take the dr6 contents as argument instead of
	a i386_debug_reg_state.
	(i386_insert_aligned_watchpoint): Adjust.
	(i386_remove_aligned_watchpoint): Adjust.
	(i386_low_stopped_data_address): Read the debug registers from the
	inferior instead of from the mirrors.
	* i386-low.h (struct i386_debug_reg_state): Extend comment.
	(i386_dr_low_get_addr): Declare.
	(i386_dr_low_get_control): Declare.
	(i386_dr_low_get_status): Change prototype.

	* win32-i386-low.c (dr_status_mirror, dr_control_mirror): New globals.
	(i386_dr_low_get_addr): New.
	(i386_dr_low_get_control): New.
	(i386_dr_low_get_status): Adjust prototype.  Return
	dr_status_mirror.
	(i386_initial_stuff): Clear dr_status_mirror and
	dr_control_mirror.
	(i386_get_thread_context): Adjust.
	(i386_set_thread_context): Adjust.
	(i386_thread_added): Adjust.

1 files changed, 12 insertions, 4 deletions

diff --git a/gdb/gdbserver/i386-low.h b/gdb/gdbserver/i386-low.h
index 7f7f76b..2566b7b 100644
--- a/gdb/gdbserver/i386-low.h
+++ b/gdb/gdbserver/i386-low.h
@@ -42,7 +42,10 @@
 struct i386_debug_reg_state
 {
   /* Mirror the inferior's DRi registers.  We keep the status and
-     control registers separated because they don't hold addresses.  */
+     control registers separated because they don't hold addresses.
+     Note that since we can change these mirrors while threads are
+     running, we never trust them to explain a cause of a trap.
+     For that, we need to peek directly in the inferior registers.  */
   CORE_ADDR dr_mirror[DR_NADDR];
   unsigned dr_status_mirror, dr_control_mirror;
 
@@ -100,9 +103,14 @@ extern int i386_low_stopped_by_watchpoint (struct i386_debug_reg_state *state);
 extern void i386_dr_low_set_addr (const struct i386_debug_reg_state *state,
 				  int regnum);
 
+/* Return the inferior's debug register REGNUM.  */
+extern CORE_ADDR i386_dr_low_get_addr (int regnum);
+
 /* Update the inferior's DR7 debug control register from STATE.  */
 extern void i386_dr_low_set_control (const struct i386_debug_reg_state *state);
 
-/* Get the value of the inferior's DR6 debug status register
-   and record it in STATE.  */
-extern void i386_dr_low_get_status (struct i386_debug_reg_state *state);
+/* Return the value of the inferior's DR7 debug control register.  */
+extern unsigned i386_dr_low_get_control (void);
+
+/* Return the value of the inferior's DR6 debug status register.  */
+extern unsigned i386_dr_low_get_status (void);