<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, 25 insertions, 0 deletions

diff --git a/lldb/tools/debugserver/source/DNB.cpp b/lldb/tools/debugserver/source/DNB.cpp
index dd54c6a7b09..b7feeb3a249 100644
--- a/lldb/tools/debugserver/source/DNB.cpp
+++ b/lldb/tools/debugserver/source/DNB.cpp
@@ -1765,6 +1765,31 @@ DNBThreadSetRegisterContext (nub_process_t pid, nub_thread_t tid, const void *bu
     return 0;
 }
 
+uint32_t
+DNBThreadSaveRegisterState (nub_process_t pid, nub_thread_t tid)
+{
+    if (tid != INVALID_NUB_THREAD)
+    {
+        MachProcessSP procSP;
+        if (GetProcessSP (pid, procSP))
+            return procSP->GetThreadList().SaveRegisterState (tid);
+    }
+    return 0;    
+}
+nub_bool_t
+DNBThreadRestoreRegisterState (nub_process_t pid, nub_thread_t tid, uint32_t save_id)
+{
+    if (tid != INVALID_NUB_THREAD)
+    {
+        MachProcessSP procSP;
+        if (GetProcessSP (pid, procSP))
+            return procSP->GetThreadList().RestoreRegisterState (tid, save_id);
+    }
+    return false;
+}
+
+
+
 //----------------------------------------------------------------------
 // Read a register value by name.
 //----------------------------------------------------------------------