Introduce common-regcache.h

This introduces common-regcache.h.  This contains two functions that
allow nat/linux-btrace.c to be simplified.  A better long term
solution would be unify the regcache code, but this is sufficient for
now.

gdb/ChangeLog:

	* common/common-regcache.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add common/common-regcache.h.
	* regcache.h: Include common-regcache.h.
	(regcache_read_pc): Don't declare.
	* regcache.c (get_thread_regcache_for_ptid): New function.
	* nat/linux-btrace.c: Don't include regcache.h.
	Include common-regcache.h.
	(perf_event_read_bts): Use get_thread_regcache_for_ptid.

gdb/gdbserver/ChangeLog:

	* regcache.h: Include common-regcache.h.
	(regcache_read_pc): Don't declare.
	* regcache.c (get_thread_regcache_for_ptid): New function.

1 files changed, 3 insertions, 1 deletions

diff --git a/gdb/gdbserver/regcache.h b/gdb/gdbserver/regcache.h
index 891fead..bf2e51f 100644
--- a/gdb/gdbserver/regcache.h
+++ b/gdb/gdbserver/regcache.h
@@ -19,6 +19,8 @@
 #ifndef REGCACHE_H
 #define REGCACHE_H
 
+#include "common-regcache.h"
+
 struct thread_info;
 struct target_desc;
 
@@ -91,7 +93,7 @@ void registers_to_string (struct regcache *regcache, char *buf);
 
 void registers_from_string (struct regcache *regcache, char *buf);
 
-CORE_ADDR regcache_read_pc (struct regcache *regcache);
+/* For regcache_read_pc see common/common-regcache.h.  */
 
 void regcache_write_pc (struct regcache *regcache, CORE_ADDR pc);