Class readonly_detached_regcache

This patch adds a new class (type) for readonly regcache, which is
created via regcache::save.  readonly_detached_regcache inherits
readable_regcache.

gdb:

2018-02-21  Yao Qi  <yao.qi@linaro.org>

	* dummy-frame.c (dummy_frame_cache) <prev_regcache>: Use
	readonly_detached_regcache.
	(dummy_frame_prev_register): Use regcache->cooked_read.
	* frame.c (frame_save_as_regcache): Change return type.
	(frame_pop): Update.
	* frame.h (frame_save_as_regcache): Update declaration.
	* inferior.h (get_infcall_suspend_state_regcache): Update
	declaration.
	* infrun.c (infcall_suspend_state) <registers>: use
	readonly_detached_regcache.
	(save_infcall_suspend_state): Don't use regcache_dup.
	(get_infcall_suspend_state_regcache): Change return type.
	* linux-fork.c (struct fork_info) <savedregs>: Change to
	readonly_detached_regcache.
	<pc>: New field.
	(fork_save_infrun_state): Don't use regcache_dup.
	(info_checkpoints_command): Adjust.
	* mi/mi-main.c (register_changed_p): Update declaration.
	(mi_cmd_data_list_changed_registers): Use
	readonly_detached_regcache.
	(register_changed_p): Change parameter type to
	readonly_detached_regcache.
	* ppc-linux-tdep.c (ppu2spu_cache) <regcache>: Use
	readonly_detached_regcache.
	(ppu2spu_sniffer): Construct a new readonly_detached_regcache.
	* regcache.c (readonly_detached_regcache::readonly_detached_regcache):
	New.
	(regcache::save): Move it to reg_buffer.
	(regcache::restore): Change parameter type.
	(regcache_dup): Remove.
	* regcache.h (reg_buffer) <save>: New method.
	(readonly_detached_regcache): New class.
	* spu-tdep.c (spu2ppu_cache) <regcache>: Use
	readonly_detached_regcache.
	(spu2ppu_sniffer): Construct a new readonly_detached_regcache.

1 files changed, 6 insertions, 6 deletions

diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
index 51d33c9..1716a7f 100644
--- a/gdb/mi/mi-main.c
+++ b/gdb/mi/mi-main.c
@@ -96,8 +96,8 @@ static void mi_execute_cli_command (const char *cmd, int args_p,
 				    const char *args);
 static void mi_execute_async_cli_command (const char *cli_command,
 					  char **argv, int argc);
-static bool register_changed_p (int regnum, regcache *,
-				regcache *);
+static bool register_changed_p (int regnum, readonly_detached_regcache *,
+			       readonly_detached_regcache *);
 static void output_register (struct frame_info *, int regnum, int format,
 			     int skip_unavailable);
 
@@ -931,9 +931,9 @@ mi_cmd_data_list_register_names (const char *command, char **argv, int argc)
 void
 mi_cmd_data_list_changed_registers (const char *command, char **argv, int argc)
 {
-  static std::unique_ptr<struct regcache> this_regs;
+  static std::unique_ptr<readonly_detached_regcache> this_regs;
   struct ui_out *uiout = current_uiout;
-  std::unique_ptr<struct regcache> prev_regs;
+  std::unique_ptr<readonly_detached_regcache> prev_regs;
   struct gdbarch *gdbarch;
   int regnum, numregs;
   int i;
@@ -995,8 +995,8 @@ mi_cmd_data_list_changed_registers (const char *command, char **argv, int argc)
 }
 
 static bool
-register_changed_p (int regnum, struct regcache *prev_regs,
-		    struct regcache *this_regs)
+register_changed_p (int regnum, readonly_detached_regcache *prev_regs,
+		    readonly_detached_regcache *this_regs)
 {
   struct gdbarch *gdbarch = this_regs->arch ();
   struct value *prev_value, *this_value;