Move current_regcache to regcache::current_regcache

This patches moves global variable current_regcache to a class regcache
static variable (protected) so that the unit test I add in the following
patch can access it (by means of extending class regcache in unit test).

gdb:

2017-05-24  Yao Qi  <yao.qi@linaro.org>

	* regcache.c (current_regcache): Change it to
	regcache::current_regcache.
	(regcache_observer_target_changed): Update.
	(regcache_thread_ptid_changed): Make it a regcache static
	method.
	(regcache_thread_ptid_changed): Update.
	(class regcache_access): New.
	(current_regcache_test): Update.
	(_initialize_regcache): Update.
	* regcache.h: Include forward_list.
	(regcache): Declare regcache_thread_ptid_changed and declare
	registers_changed_ptid as friend.

1 files changed, 9 insertions, 1 deletions

diff --git a/gdb/regcache.h b/gdb/regcache.h
index da00abd..fdc47ba 100644
--- a/gdb/regcache.h
+++ b/gdb/regcache.h
@@ -21,6 +21,7 @@
 #define REGCACHE_H
 
 #include "common-regcache.h"
+#include <forward_list>
 
 struct regcache;
 struct regset;
@@ -336,9 +337,13 @@ public:
    debug.  */
   void debug_print_register (const char *func, int regno);
 
-private:
+  static void regcache_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid);
+protected:
   regcache (gdbarch *gdbarch, address_space *aspace_, bool readonly_p_);
 
+  static std::forward_list<regcache *> current_regcache;
+
+private:
   gdb_byte *register_buffer (int regnum) const;
 
   void restore (struct regcache *src);
@@ -383,6 +388,9 @@ private:
 				   struct address_space *aspace);
 
   friend void
+  registers_changed_ptid (ptid_t ptid);
+
+  friend void
   regcache_cpy (struct regcache *dst, struct regcache *src);
 };