gdb/

2011-12-14  Pedro Alves  <pedro@codesourcery.com>

	PR threads/10729

	* linux-nat.c (linux_nat_new_thread): Change parameter to an lwp
	pointer.
	(linux_nat_prepare_to_resume): New global.
	(lwp_free): New.
	(purge_lwp_list): Use it.
	(add_lwp): Call linux_nat_new_thread even on the first LWP.
	Adjust to interface change.
	(delete_lwp): Call lwp_free instead of xfree.
	(detach_callback, linux_nat_detach, resume_lwp, linux_nat_resume)
	(linux_handle_syscall_trap, linux_handle_extended_wait)
	(linux_nat_filter_event, resume_stopped_resumed_lwps): Call
	linux_nat_prepare_to_resume before resuming.
	(linux_stop_lwp): New.
	(linux_nat_set_new_thread): Adjust.
	(linux_nat_set_prepare_to_resume): New.
	* linux-nat.h (struct arch_lwp_info): Forward declare.
	(struct lwp_info) <arch_private>: New field.
	(linux_stop_lwp): Declare.
	(linux_nat_set_new_thread): Adjust.
	(linux_nat_set_prepare_to_resume): New.

	* i386-nat.c (DR_NADDR, DR_STATUS, DR_CONTROL)
	(struct i386_debug_reg_state): Move to i386-nat.h.
	(dr_mirror): Comment.
	(i386_debug_reg_state): New.
	(i386_update_inferior_debug_regs): Simplify.
	(i386_stopped_data_address): Use the debug register state from the
	inferior, not from the local cache.
	* i386-nat.h (struct i386_dr_low_type): Delete reset_addr and
	unset_status fields.  New get_addr and get_control fields.
	(DR_FIRSTADDR, DR_LASTADDR, DR_CONTROL): Moved from i386-nat.c.
	(DR_NADDR, DR_STATUS): New.
	(struct i386_debug_reg_state): Moved from i386-nat.c.

	* amd64-linux-nat.c (struct arch_lwp_info): New.
	(amd64_linux_dr): Delete global.
	(amd64_linux_dr_get_addr): New.
	(amd64_linux_dr_get_control): New.
	(amd64_linux_dr_unset_status): Delete.
	(amd64_linux_dr_set_addr): Reimplement.
	(amd64_linux_dr_reset_addr): Delete.
	(update_debug_registers_callback): New.
	(amd64_linux_dr_set_control): Reimplement.
	(amd64_linux_dr_set_addr): Reimplement.
	(amd64_linux_prepare_to_resume): New.
	(amd64_linux_new_thread): Change parameter to an lwp pointer.
	Reimplement.
	(_initialize_amd64_linux_nat): No longer install
	i386_dr_low.reset_addr and i386_dr_low.unset_status.  Install
	amd64_linux_dr_get_control as i386_dr_low.get_control.  Install
	amd64_linux_dr_get_addr as i386_dr_low.get_addr.  Install
	amd64_linux_prepare_to_resume.
	* i386-linux-nat.c (DR_FIRSTADDR, DR_LASTADDR, DR_STATUS)
	(DR_CONTROL): Delete.
	(struct arch_lwp_info): New.
	(i386_linux_dr): Delete global.
	(i386_linux_dr_set_control): Reimplement.
	(i386_linux_dr_get_addr): New.
	(i386_linux_dr_set_addr): Reimplement.
	(i386_linux_dr_get_control): New.
	(update_debug_registers_callback): New.
	(i386_linux_dr_unset_status): Delete.
	(i386_linux_dr_set_addr): Reimplement.
	(i386_linux_prepare_to_resume): New.
	(i386_linux_new_thread): Change parameter to an lwp pointer.
	Reimplement.
	(_initialize_i386_linux_nat): No longer install
	i386_dr_low.reset_addr and i386_dr_low.unset_status.  Install
	i386_linux_dr_get_control as i386_dr_low.get_control.  Install
	i386_linux_dr_get_addr as i386_dr_low.get_addr.  Install
	i386_linux_prepare_to_resume.

	* arm-linux-nat.c (arm_linux_new_thread): Change parameter to an
	lwp pointer.  Adjust.
	* ia64-linux-nat.c (ia64_linux_new_thread): Likewise.
	* mips-linux-nat.c (mips_linux_new_thread): Likewise.
	* ppc-linux-nat.c (ppc_linux_new_thread): Likewise.
	* s390-nat.c (s390_fix_watch_points): Likewise.

	* i386-darwin-nat.c (DR_FIRSTADDR, DR_LASTADDR, DR_STATUS)
	(DR_CONTROL): Delete.
	(i386_darwin_dr_reset_addr): Delete.
	(i386_darwin_dr_get_addr): New.
	(i386_darwin_dr_get_control): New.
	* go32-nat.c
	(go32_get_dr7, go32_get_dr): New.
	(init_go32_ops): No longer install i386_dr_low.reset_addr.
	Install go32_get_dr7 as i386_dr_low.get_control.  Install
	go32_get_dr as i386_dr_low.get_addr.
	* i386bsd-nat.c (i386bsd_dr_get): New.
	(i386bsd_dr_reset_addr): Delete.
	(i386bsd_dr_get_addr): New.
	(i386bsd_dr_get_status): Use i386bsd_dr_get.
	(i386bsd_dr_get_control): New.
	* i386bsd-nat.h (i386bsd_dr_reset_addr): Delete.
	(i386bsd_dr_get_addr): New.
	(i386bsd_dr_get_control): New.
	* i386fbsd-nat.c (_initialize_i386fbsd_nat): No longer install
	i386_dr_low.reset_addr and i386_dr_low.unset_status.  Install
	i386bsd_dr_get_control as i386_dr_low.get_control.  Install
	i386bsd_dr_get_addr as i386_dr_low.get_addr.
	* windows-nat.c (init_windows_ops): No longer install
	i386_dr_low.reset_addr and i386_dr_low.unset_status.  Install
	cygwin_get_dr7 as i386_dr_low.get_control.  Install cygwin_get_dr
	as i386_dr_low.get_addr.
	(cygwin_get_dr): New.
	(cygwin_get_dr7): New.

gdb/testsuite/
2011-12-14  Pedro Alves  <pedro@codesourcery.com>

	PR threads/10729

	* gdb.mi/watch-nonstop.c: New file.
 	* gdb.mi/mi-watch-nonstop.exp: New file.

1 files changed, 35 insertions, 7 deletions

diff --git a/gdb/i386-nat.h b/gdb/i386-nat.h
index 819c6b8e656..1a75daa80e2 100644
--- a/gdb/i386-nat.h
+++ b/gdb/i386-nat.h
@@ -53,31 +53,54 @@ extern void i386_use_watchpoints (struct target_ops *);
       set_addr                 -- put an address into one debug
 				  register for all LWPs
 
-      reset_addr               -- reset the address stored in
-				  one debug register for all LWPs
+      get_addr                 -- return the address in a given debug
+				  register of the current LWP
 
       get_status               -- return the value of the debug
 				  status (DR6) register for current LWP
 
-      unset_status             -- unset the specified bits of the debug
-				  status (DR6) register for all LWPs
+      get_control               -- return the value of the debug
+				  control (DR7) register for current LWP
 
    Additionally, the native file should set the debug_register_length
    field to 4 or 8 depending on the number of bytes used for
    deubg registers.  */
 
-struct i386_dr_low_type 
+struct i386_dr_low_type
   {
     void (*set_control) (unsigned long);
     void (*set_addr) (int, CORE_ADDR);
-    void (*reset_addr) (int);
+    CORE_ADDR (*get_addr) (int);
     unsigned long (*get_status) (void);
-    void (*unset_status) (unsigned long);
+    unsigned long (*get_control) (void);
     int debug_register_length;
   };
 
 extern struct i386_dr_low_type i386_dr_low;
 
+/* Debug registers' indices.  */
+#define DR_FIRSTADDR 0
+#define DR_LASTADDR  3
+#define DR_NADDR     4	/* The number of debug address registers.  */
+#define DR_STATUS    6	/* Index of debug status register (DR6).  */
+#define DR_CONTROL   7	/* Index of debug control register (DR7).  */
+
+/* Global state needed to track h/w watchpoints.  */
+
+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.
+     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;
+
+  /* Reference counts for each debug register.  */
+  int dr_ref_count[DR_NADDR];
+};
+
 /* Use this function to set i386_dr_low debug_register_length field
    rather than setting it directly to check that the length is only
    set once.  It also enables the 'maint set/show show-debug-regs' 
@@ -89,4 +112,9 @@ extern void i386_set_debug_register_length (int len);
 
 extern void i386_cleanup_dregs (void);
 
+/* Return a pointer to the the local mirror of the inferior's debug
+   registers.  */
+
+extern struct i386_debug_reg_state *i386_debug_reg_state (void);
+
 #endif /* I386_NAT_H */