Merge GDB 7.5.1

gdb/i386-nat.h

 /* Native-dependent code for the i386.
 
    Low level functions to implement Oeprating System specific
    code to manipulate I386 debug registers.
 
    Copyright (C) 2009-2012 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
    This program is free software; you can redistribute it and/or modify
@@ skipping 35 matching lines @@
    that will be called to insert watchpoints and hardware breakpoints
    into the inferior, remove them, and check their status.  These
    functions are:
 
       set_control              -- set the debug control (DR7)
                                   register to a given value for all LWPs
 
       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' 
    command.  */
 
 extern void i386_set_debug_register_length (int len);
 
 /* Use this function to reset the i386-nat.c debug register state.  */
 
 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 */