regcache_raw and use it in to_{fetch,store}_registers

regcache_raw and use it in to_{fetch,store}_registers

This patch adds a new class regcache_raw, between reg_buffer and regcache
in the class hierarchy.  Also use it in target_ops
to_{fetch,store}_registers methods, because target_ops accesses raw
registers.  (pseudo registers are abstracted by gdbarch).

gdb:

2017-10-03  Yao Qi  <yao.qi@linaro.org>
:
	* aarch32-linux-nat.c (aarch32_gp_regcache_supply): -
	(aarch32_gp_regcache_supply): +
	(aarch32_gp_regcache_supply):
	(aarch32_gp_regcache_collect): -
	(aarch32_gp_regcache_collect): +
	(aarch32_gp_regcache_collect):
	(aarch32_vfp_regcache_supply): -
	(aarch32_vfp_regcache_supply): +
	(aarch32_vfp_regcache_supply):
	(aarch32_vfp_regcache_collect): -
	(aarch32_vfp_regcache_collect): +
	* aarch32-linux-nat.h:
	* aarch64-linux-nat.c (aarch64_get_debug_reg_state):
	(fetch_gregs_from_thread): -
	(fetch_gregs_from_thread): +
	(fetch_gregs_from_thread):
	(store_gregs_to_thread): -
	(store_gregs_to_thread): +
	(store_gregs_to_thread):
	(fetch_fpregs_from_thread): -
	(fetch_fpregs_from_thread): +
	(fetch_fpregs_from_thread):
	(store_fpregs_to_thread): -
	(store_fpregs_to_thread): +
	(store_fpregs_to_thread):
	(aarch64_linux_fetch_inferior_registers):
	* arch-utils.c (default_addressable_memory_unit_size):
	* arch-utils.h (extern const char *default_gnu_triplet_regexp):
	* arm-linux-tdep.c (static struct tramp_frame arm_kernel_linux_restart_syscall_tramp_frame = {):
	(arm_linux_supply_gregset):
	(arm_linux_collect_gregset):
	(supply_nwfpe_register): -
	(supply_nwfpe_register): +
	(supply_nwfpe_register):
	(collect_nwfpe_register): -
	(collect_nwfpe_register): +
	(collect_nwfpe_register):
	(arm_linux_supply_nwfpe):
	(arm_linux_collect_nwfpe):
	(arm_linux_supply_vfp):
	* arm-linux-tdep.h (void arm_linux_collect_gregset):
	* corelow.c (core_detach):
	(get_core_register_section): -
	(get_core_register_section): +
	(get_core_registers_cb):
	* gdbarch.c (set_gdbarch_fast_tracepoint_valid_at):
	(gdbarch_guess_tracepoint_registers): -
	(gdbarch_guess_tracepoint_registers): +
	* gdbarch.h (extern void set_gdbarch_fast_tracepoint_valid_at):
	* gdbarch.sh (m;int;fast_tracepoint_valid_at;CORE_ADDR addr, char **msg;addr, msg;;default_fas):
	* gdbcore.h (struct core_fns):
	* inf-child.c (store_waitstatus):
	(inf_child_fetch_inferior_registers):
	(inf_child_post_attach):
	* inf-ptrace.c (static CORE_ADDR):
	(inf_ptrace_fetch_register): -
	(inf_ptrace_fetch_register): +
	(inf_ptrace_fetch_register):
	(inf_ptrace_fetch_registers):
	(inf_ptrace_store_register): -
	(inf_ptrace_store_register): +
	(inf_ptrace_store_register):
	* record-btrace.c (record_btrace_remove_breakpoint):
	(record_btrace_fetch_registers):
	(record_btrace_store_registers):
	* record-full.c (static void record_full_save):
	(record_full_reg_alloc): -
	(record_full_reg_alloc): +
	(record_full_get_loc):
	(record_full_arch_list_add_reg): -
	(record_full_arch_list_add_reg): +
	(record_full_supports_stopped_by_hw_breakpoint):
	(record_full_registers_change): -
	(record_full_registers_change): +
	(record_full_registers_change):
	(record_full_core_kill):
	(record_full_core_fetch_registers):
	(record_full_core_prepare_to_store):
	* record-full.h:
	* regcache.c (regcache_register_size):
	(regcache::regcache):
	(regcache::arch):
	(regcache_get_ptid): -
	(regcache_get_ptid): +
	(class regcache_invalidator):
	(public:):
	(public:):
	(get_regcache_arch): -
	(get_regcache_arch): +
	(regcache_dup):
	(regcache_register_status): -
	(regcache_register_status): +
	(reg_buffer::set_register_status):
	(regcache_invalidate): -
	(regcache_invalidate): +
	(registers_changed):
	(regcache_raw_update): -
	(regcache_raw_update): +
	(regcache_raw_update):
	(regcache::raw_update):
	(regcache_raw_read): -
	(regcache_raw_read): +
	(regcache_raw_read_signed):
	(regcache_raw_write_signed):
	(regcache_raw_write):
	(reg_buffer::raw_supply_zeroed):
	(regcache_raw_collect): -
	(regcache_raw_collect): +
	(reg_buffer::transfer_regset):
	(reg_buffer::supply_regset):
	(regcache_write_pc):
	* regcache.h (struct regcache;):
	(extern struct regcache *get_thread_arch_aspace_regcache):
	(extern enum register_status):
	(extern void regcache_write_pc):
	(enum):
	(private:):
	(public:):
	(public:):
	(public:):
	(public:):
	(private:):
	* regset.h (struct regcache;):
	* remote.c (static int getpkt_or_notif_sane):
	(remote_wait):
	(fetch_register_using_p): -
	(fetch_register_using_p): +
	(send_g_packet):
	(process_g_packet): -
	(process_g_packet): +
	(process_g_packet):
	(fetch_registers_using_g): -
	(fetch_registers_using_g): +
	(set_remote_traceframe):
	(remote_fetch_registers):
	(remote_prepare_to_store): -
	(remote_prepare_to_store): +
	(remote_prepare_to_store):
	(store_register_using_P): -
	(store_register_using_P): +
	(store_register_using_P):
	(store_registers_using_G): -
	(store_registers_using_G): +
	(store_registers_using_G):
	* s390-linux-tdep.c (s390_write_pc):
	* target-debug.h:
	* target-delegates.c (debug_wait):
	(delegate_fetch_registers): -
	(delegate_fetch_registers): +
	(tdefault_fetch_registers): -
	(tdefault_fetch_registers): +
	(debug_fetch_registers): -
	(debug_fetch_registers): +
	(delegate_store_registers): -
	(delegate_store_registers): +
	(tdefault_store_registers): -
	(tdefault_store_registers): +
	(debug_store_registers): -
	(debug_store_registers): +
	(delegate_prepare_to_store): -
	(delegate_prepare_to_store): +
	(tdefault_prepare_to_store): -
	(tdefault_prepare_to_store): +
	(debug_prepare_to_store): -
	(debug_prepare_to_store): +
	* target.c (target_options_to_string):
	(target_fetch_registers): -
	(target_fetch_registers): +
	(target_fetch_registers):
	(target_store_registers): -
	(target_store_registers): +
	* target.h (struct target_ops):
	(extern ptid_t default_target_wait):
	* tracefile-tfile.c (traceframe_find_block_type):
	* tracefile.c (trace_save_ctf):
	(tracefile_fetch_registers): -
	(tracefile_fetch_registers): +
	* tracefile.h (extern struct trace_file_writer *tfile_trace_file_writer_new):