<rdar://problem/15172417>

Added two new GDB server packets to debugserver: "QSaveRegisterState" and "QRestoreRegiterState".

"QSaveRegisterState" makes the remote GDB server save all register values and it returns a save identifier as an unsigned integer. This packet can be used prior to running expressions to save all registers.

All registers can them we later restored with "QRestoreRegiterState:SAVEID" what SAVEID is the integer identifier that was returned from the call to QSaveRegisterState.

Cleaned up redundant code in lldb_private::Thread, lldb_private::ThreadPlanCallFunction.
Moved the lldb_private::Thread::RegisterCheckpoint into its own header file and it is now in the lldb_private namespace. Trimmed down the RegisterCheckpoint class to omit stuff that wasn't used (the stack ID).

Added a few new virtual methods to lldb_private::RegisterContext that allow subclasses to efficiently save/restore register states and changed the RegisterContextGDBRemote to take advantage of these new calls.

llvm-svn: 194621
diff --git a/lldb/tools/debugserver/source/DNB.h b/lldb/tools/debugserver/source/DNB.h
index 986cab9..c70ede9 100644
--- a/lldb/tools/debugserver/source/DNB.h
+++ b/lldb/tools/debugserver/source/DNB.h
@@ -18,8 +18,6 @@
 #include <mach/thread_info.h>
 #include <string>
 
-#define DNB_EXPORT __attribute__((visibility("default")))
-
 typedef bool (*DNBShouldCancelCallback) (void *);
 
 void            DNBInitialize ();
@@ -41,11 +39,11 @@
                                          nub_launch_flavor_t launch_flavor, 
                                          int disable_aslr, 
                                          char *err_str, 
-                                         size_t err_len) DNB_EXPORT;
+                                         size_t err_len);
 
-nub_process_t   DNBProcessAttach        (nub_process_t pid, struct timespec *timeout, char *err_str, size_t err_len) DNB_EXPORT;
-nub_process_t   DNBProcessAttachByName  (const char *name, struct timespec *timeout, char *err_str, size_t err_len) DNB_EXPORT;
-nub_process_t   DNBProcessAttachWait    (const char *wait_name, nub_launch_flavor_t launch_flavor, bool ignore_existing, struct timespec *timeout, useconds_t interval, char *err_str, size_t err_len, DNBShouldCancelCallback should_cancel = NULL, void *callback_data = NULL) DNB_EXPORT;
+nub_process_t   DNBProcessAttach        (nub_process_t pid, struct timespec *timeout, char *err_str, size_t err_len);
+nub_process_t   DNBProcessAttachByName  (const char *name, struct timespec *timeout, char *err_str, size_t err_len);
+nub_process_t   DNBProcessAttachWait    (const char *wait_name, nub_launch_flavor_t launch_flavor, bool ignore_existing, struct timespec *timeout, useconds_t interval, char *err_str, size_t err_len, DNBShouldCancelCallback should_cancel = NULL, void *callback_data = NULL);
 // Resume a process with exact instructions on what to do with each thread:
 // - If no thread actions are supplied (actions is NULL or num_actions is zero),
 //   then all threads are continued.
@@ -54,97 +52,99 @@
 //   explicit thread action can be made by making a thread action with a tid of
 //   INVALID_NUB_THREAD. If there is no default action, those threads will
 //   remain stopped.
-nub_bool_t      DNBProcessResume        (nub_process_t pid, const DNBThreadResumeAction *actions, size_t num_actions) DNB_EXPORT;
-nub_bool_t      DNBProcessHalt          (nub_process_t pid) DNB_EXPORT;
-nub_bool_t      DNBProcessDetach        (nub_process_t pid) DNB_EXPORT;
-nub_bool_t      DNBProcessSignal        (nub_process_t pid, int signal) DNB_EXPORT;
-nub_bool_t      DNBProcessKill          (nub_process_t pid) DNB_EXPORT;
-nub_size_t      DNBProcessMemoryRead    (nub_process_t pid, nub_addr_t addr, nub_size_t size, void *buf) DNB_EXPORT;
-nub_size_t      DNBProcessMemoryWrite   (nub_process_t pid, nub_addr_t addr, nub_size_t size, const void *buf) DNB_EXPORT;
-nub_addr_t      DNBProcessMemoryAllocate    (nub_process_t pid, nub_size_t size, uint32_t permissions) DNB_EXPORT;
-nub_bool_t      DNBProcessMemoryDeallocate  (nub_process_t pid, nub_addr_t addr) DNB_EXPORT;
-int             DNBProcessMemoryRegionInfo  (nub_process_t pid, nub_addr_t addr, DNBRegionInfo *region_info) DNB_EXPORT;
-std::string     DNBProcessGetProfileData (nub_process_t pid, DNBProfileDataScanType scanType) DNB_EXPORT;
-nub_bool_t      DNBProcessSetEnableAsyncProfiling   (nub_process_t pid, nub_bool_t enable, uint64_t interval_usec, DNBProfileDataScanType scan_type) DNB_EXPORT;
+nub_bool_t      DNBProcessResume        (nub_process_t pid, const DNBThreadResumeAction *actions, size_t num_actions);
+nub_bool_t      DNBProcessHalt          (nub_process_t pid);
+nub_bool_t      DNBProcessDetach        (nub_process_t pid);
+nub_bool_t      DNBProcessSignal        (nub_process_t pid, int signal);
+nub_bool_t      DNBProcessKill          (nub_process_t pid);
+nub_size_t      DNBProcessMemoryRead    (nub_process_t pid, nub_addr_t addr, nub_size_t size, void *buf);
+nub_size_t      DNBProcessMemoryWrite   (nub_process_t pid, nub_addr_t addr, nub_size_t size, const void *buf);
+nub_addr_t      DNBProcessMemoryAllocate    (nub_process_t pid, nub_size_t size, uint32_t permissions);
+nub_bool_t      DNBProcessMemoryDeallocate  (nub_process_t pid, nub_addr_t addr);
+int             DNBProcessMemoryRegionInfo  (nub_process_t pid, nub_addr_t addr, DNBRegionInfo *region_info);
+std::string     DNBProcessGetProfileData (nub_process_t pid, DNBProfileDataScanType scanType);
+nub_bool_t      DNBProcessSetEnableAsyncProfiling   (nub_process_t pid, nub_bool_t enable, uint64_t interval_usec, DNBProfileDataScanType scan_type);
 
 //----------------------------------------------------------------------
 // Process status
 //----------------------------------------------------------------------
-nub_bool_t      DNBProcessIsAlive                       (nub_process_t pid) DNB_EXPORT;
-nub_state_t     DNBProcessGetState                      (nub_process_t pid) DNB_EXPORT;
-nub_bool_t      DNBProcessGetExitStatus                 (nub_process_t pid, int *status) DNB_EXPORT;
-nub_bool_t      DNBProcessSetExitStatus                 (nub_process_t pid, int status) DNB_EXPORT;
-nub_size_t      DNBProcessGetNumThreads                 (nub_process_t pid) DNB_EXPORT;
-nub_thread_t    DNBProcessGetCurrentThread              (nub_process_t pid) DNB_EXPORT;
-nub_thread_t    DNBProcessGetCurrentThreadMachPort      (nub_process_t pid) DNB_EXPORT;
-nub_thread_t    DNBProcessSetCurrentThread              (nub_process_t pid, nub_thread_t tid) DNB_EXPORT;
-nub_thread_t    DNBProcessGetThreadAtIndex              (nub_process_t pid, nub_size_t thread_idx) DNB_EXPORT;
-nub_bool_t      DNBProcessSyncThreadState               (nub_process_t pid, nub_thread_t tid) DNB_EXPORT;
-nub_addr_t      DNBProcessGetSharedLibraryInfoAddress   (nub_process_t pid) DNB_EXPORT;
-nub_bool_t      DNBProcessSharedLibrariesUpdated        (nub_process_t pid) DNB_EXPORT;
-nub_size_t      DNBProcessGetSharedLibraryInfo          (nub_process_t pid, nub_bool_t only_changed, DNBExecutableImageInfo **image_infos) DNB_EXPORT;
-nub_bool_t      DNBProcessSetNameToAddressCallback      (nub_process_t pid, DNBCallbackNameToAddress callback, void *baton) DNB_EXPORT;
-nub_bool_t      DNBProcessSetSharedLibraryInfoCallback  (nub_process_t pid, DNBCallbackCopyExecutableImageInfos callback, void *baton) DNB_EXPORT;
-nub_addr_t      DNBProcessLookupAddress                 (nub_process_t pid, const char *name, const char *shlib) DNB_EXPORT;
-nub_size_t      DNBProcessGetAvailableSTDOUT            (nub_process_t pid, char *buf, nub_size_t buf_size) DNB_EXPORT;
-nub_size_t      DNBProcessGetAvailableSTDERR            (nub_process_t pid, char *buf, nub_size_t buf_size) DNB_EXPORT;
-nub_size_t      DNBProcessGetAvailableProfileData       (nub_process_t pid, char *buf, nub_size_t buf_size) DNB_EXPORT;
-nub_size_t      DNBProcessGetStopCount                  (nub_process_t pid) DNB_EXPORT;
-uint32_t        DNBProcessGetCPUType                    (nub_process_t pid) DNB_EXPORT; 
+nub_bool_t      DNBProcessIsAlive                       (nub_process_t pid);
+nub_state_t     DNBProcessGetState                      (nub_process_t pid);
+nub_bool_t      DNBProcessGetExitStatus                 (nub_process_t pid, int *status);
+nub_bool_t      DNBProcessSetExitStatus                 (nub_process_t pid, int status);
+nub_size_t      DNBProcessGetNumThreads                 (nub_process_t pid);
+nub_thread_t    DNBProcessGetCurrentThread              (nub_process_t pid);
+nub_thread_t    DNBProcessGetCurrentThreadMachPort      (nub_process_t pid);
+nub_thread_t    DNBProcessSetCurrentThread              (nub_process_t pid, nub_thread_t tid);
+nub_thread_t    DNBProcessGetThreadAtIndex              (nub_process_t pid, nub_size_t thread_idx);
+nub_bool_t      DNBProcessSyncThreadState               (nub_process_t pid, nub_thread_t tid);
+nub_addr_t      DNBProcessGetSharedLibraryInfoAddress   (nub_process_t pid);
+nub_bool_t      DNBProcessSharedLibrariesUpdated        (nub_process_t pid);
+nub_size_t      DNBProcessGetSharedLibraryInfo          (nub_process_t pid, nub_bool_t only_changed, DNBExecutableImageInfo **image_infos);
+nub_bool_t      DNBProcessSetNameToAddressCallback      (nub_process_t pid, DNBCallbackNameToAddress callback, void *baton);
+nub_bool_t      DNBProcessSetSharedLibraryInfoCallback  (nub_process_t pid, DNBCallbackCopyExecutableImageInfos callback, void *baton);
+nub_addr_t      DNBProcessLookupAddress                 (nub_process_t pid, const char *name, const char *shlib);
+nub_size_t      DNBProcessGetAvailableSTDOUT            (nub_process_t pid, char *buf, nub_size_t buf_size);
+nub_size_t      DNBProcessGetAvailableSTDERR            (nub_process_t pid, char *buf, nub_size_t buf_size);
+nub_size_t      DNBProcessGetAvailableProfileData       (nub_process_t pid, char *buf, nub_size_t buf_size);
+nub_size_t      DNBProcessGetStopCount                  (nub_process_t pid);
+uint32_t        DNBProcessGetCPUType                    (nub_process_t pid); 
 
 //----------------------------------------------------------------------
 // Process executable and arguments
 //----------------------------------------------------------------------
-const char *    DNBProcessGetExecutablePath     (nub_process_t pid) DNB_EXPORT;
-const char *    DNBProcessGetArgumentAtIndex    (nub_process_t pid, nub_size_t idx) DNB_EXPORT;
-nub_size_t      DNBProcessGetArgumentCount      (nub_process_t pid) DNB_EXPORT;
+const char *    DNBProcessGetExecutablePath     (nub_process_t pid);
+const char *    DNBProcessGetArgumentAtIndex    (nub_process_t pid, nub_size_t idx);
+nub_size_t      DNBProcessGetArgumentCount      (nub_process_t pid);
 
 //----------------------------------------------------------------------
 // Process events
 //----------------------------------------------------------------------
-nub_event_t     DNBProcessWaitForEvents         (nub_process_t pid, nub_event_t event_mask, bool wait_for_set, struct timespec* timeout) DNB_EXPORT;
-void            DNBProcessResetEvents           (nub_process_t pid, nub_event_t event_mask) DNB_EXPORT;
+nub_event_t     DNBProcessWaitForEvents         (nub_process_t pid, nub_event_t event_mask, bool wait_for_set, struct timespec* timeout);
+void            DNBProcessResetEvents           (nub_process_t pid, nub_event_t event_mask);
 
 //----------------------------------------------------------------------
 // Thread functions
 //----------------------------------------------------------------------
-const char *    DNBThreadGetName                (nub_process_t pid, nub_thread_t tid) DNB_EXPORT;
-nub_bool_t      DNBThreadGetIdentifierInfo      (nub_process_t pid, nub_thread_t tid, thread_identifier_info_data_t *ident_info) DNB_EXPORT;
-nub_state_t     DNBThreadGetState               (nub_process_t pid, nub_thread_t tid) DNB_EXPORT;
-nub_bool_t      DNBThreadGetRegisterValueByID   (nub_process_t pid, nub_thread_t tid, uint32_t set, uint32_t reg, DNBRegisterValue *value) DNB_EXPORT;
-nub_bool_t      DNBThreadSetRegisterValueByID   (nub_process_t pid, nub_thread_t tid, uint32_t set, uint32_t reg, const DNBRegisterValue *value) DNB_EXPORT;
-nub_size_t      DNBThreadGetRegisterContext     (nub_process_t pid, nub_thread_t tid, void *buf, size_t buf_len) DNB_EXPORT;
-nub_size_t      DNBThreadSetRegisterContext     (nub_process_t pid, nub_thread_t tid, const void *buf, size_t buf_len) DNB_EXPORT;
-nub_bool_t      DNBThreadGetRegisterValueByName (nub_process_t pid, nub_thread_t tid, uint32_t set, const char *name, DNBRegisterValue *value) DNB_EXPORT;
-nub_bool_t      DNBThreadGetStopReason          (nub_process_t pid, nub_thread_t tid, DNBThreadStopInfo *stop_info) DNB_EXPORT;
-const char *    DNBThreadGetInfo                (nub_process_t pid, nub_thread_t tid) DNB_EXPORT;
+const char *    DNBThreadGetName                (nub_process_t pid, nub_thread_t tid);
+nub_bool_t      DNBThreadGetIdentifierInfo      (nub_process_t pid, nub_thread_t tid, thread_identifier_info_data_t *ident_info);
+nub_state_t     DNBThreadGetState               (nub_process_t pid, nub_thread_t tid);
+nub_bool_t      DNBThreadGetRegisterValueByID   (nub_process_t pid, nub_thread_t tid, uint32_t set, uint32_t reg, DNBRegisterValue *value);
+nub_bool_t      DNBThreadSetRegisterValueByID   (nub_process_t pid, nub_thread_t tid, uint32_t set, uint32_t reg, const DNBRegisterValue *value);
+nub_size_t      DNBThreadGetRegisterContext     (nub_process_t pid, nub_thread_t tid, void *buf, size_t buf_len);
+nub_size_t      DNBThreadSetRegisterContext     (nub_process_t pid, nub_thread_t tid, const void *buf, size_t buf_len);
+uint32_t        DNBThreadSaveRegisterState      (nub_process_t pid, nub_thread_t tid);
+nub_bool_t      DNBThreadRestoreRegisterState   (nub_process_t pid, nub_thread_t tid, uint32_t save_id);
+nub_bool_t      DNBThreadGetRegisterValueByName (nub_process_t pid, nub_thread_t tid, uint32_t set, const char *name, DNBRegisterValue *value);
+nub_bool_t      DNBThreadGetStopReason          (nub_process_t pid, nub_thread_t tid, DNBThreadStopInfo *stop_info);
+const char *    DNBThreadGetInfo                (nub_process_t pid, nub_thread_t tid);
 //----------------------------------------------------------------------
 // Breakpoint functions
 //----------------------------------------------------------------------
-nub_bool_t      DNBBreakpointSet                (nub_process_t pid, nub_addr_t addr, nub_size_t size, nub_bool_t hardware) DNB_EXPORT;
-nub_bool_t      DNBBreakpointClear              (nub_process_t pid, nub_addr_t addr) DNB_EXPORT;
+nub_bool_t      DNBBreakpointSet                (nub_process_t pid, nub_addr_t addr, nub_size_t size, nub_bool_t hardware);
+nub_bool_t      DNBBreakpointClear              (nub_process_t pid, nub_addr_t addr);
 
 //----------------------------------------------------------------------
 // Watchpoint functions
 //----------------------------------------------------------------------
-nub_bool_t      DNBWatchpointSet                (nub_process_t pid, nub_addr_t addr, nub_size_t size, uint32_t watch_flags, nub_bool_t hardware) DNB_EXPORT;
-nub_bool_t      DNBWatchpointClear              (nub_process_t pid, nub_addr_t addr) DNB_EXPORT;
-uint32_t        DNBWatchpointGetNumSupportedHWP (nub_process_t pid) DNB_EXPORT; 
+nub_bool_t      DNBWatchpointSet                (nub_process_t pid, nub_addr_t addr, nub_size_t size, uint32_t watch_flags, nub_bool_t hardware);
+nub_bool_t      DNBWatchpointClear              (nub_process_t pid, nub_addr_t addr);
+uint32_t        DNBWatchpointGetNumSupportedHWP (nub_process_t pid); 
 
 const DNBRegisterSetInfo *
-                DNBGetRegisterSetInfo           (nub_size_t *num_reg_sets) DNB_EXPORT;
-nub_bool_t      DNBGetRegisterInfoByName        (const char *reg_name, DNBRegisterInfo* info) DNB_EXPORT;
+                DNBGetRegisterSetInfo           (nub_size_t *num_reg_sets);
+nub_bool_t      DNBGetRegisterInfoByName        (const char *reg_name, DNBRegisterInfo* info);
 
 //----------------------------------------------------------------------
 // Printf style formatting for printing values in the inferior memory
 // space and registers.
 //----------------------------------------------------------------------
-nub_size_t      DNBPrintf (nub_process_t pid, nub_thread_t tid, nub_addr_t addr, FILE *file, const char *format) DNB_EXPORT;
+nub_size_t      DNBPrintf (nub_process_t pid, nub_thread_t tid, nub_addr_t addr, FILE *file, const char *format);
 
 //----------------------------------------------------------------------
 // Other static nub information calls.
 //----------------------------------------------------------------------
-const char *    DNBStateAsString (nub_state_t state) DNB_EXPORT;
-nub_bool_t      DNBResolveExecutablePath (const char *path, char *resolved_path, size_t resolved_path_size) DNB_EXPORT;
+const char *    DNBStateAsString (nub_state_t state);
+nub_bool_t      DNBResolveExecutablePath (const char *path, char *resolved_path, size_t resolved_path_size);
 
 #endif