<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

1 files changed, 2 insertions, 0 deletions

diff --git a/lldb/tools/debugserver/source/MacOSX/MachThreadList.h b/lldb/tools/debugserver/source/MacOSX/MachThreadList.h
index 85097314b02..46bccfee8de 100644
--- a/lldb/tools/debugserver/source/MacOSX/MachThreadList.h
+++ b/lldb/tools/debugserver/source/MacOSX/MachThreadList.h
@@ -30,6 +30,8 @@ public:
     bool            SetRegisterValue (nub_thread_t tid, uint32_t reg_set_idx, uint32_t reg_idx, const DNBRegisterValue *reg_value) const;
     nub_size_t      GetRegisterContext (nub_thread_t tid, void *buf, size_t buf_len);
     nub_size_t      SetRegisterContext (nub_thread_t tid, const void *buf, size_t buf_len);
+    uint32_t        SaveRegisterState (nub_thread_t tid);
+    bool            RestoreRegisterState (nub_thread_t tid, uint32_t save_id);
     const char *    GetThreadInfo (nub_thread_t tid) const;
     void            ProcessWillResume (MachProcess *process, const DNBThreadResumeActions &thread_actions);
     uint32_t        ProcessDidStop (MachProcess *process);