Fixed issues with RegisterContext classes and the subclasses. There was

an issue with the way the UnwindLLDB was handing out RegisterContexts: it
was making shared pointers to register contexts and then handing out just
the pointers (which would get put into shared pointers in the thread and
stack frame classes) and cause double free issues. MallocScribble helped to
find these issues after I did some other cleanup. To help avoid any
RegisterContext issue in the future, all code that deals with them now
returns shared pointers to the register contexts so we don't end up with
multiple deletions. Also now that the RegisterContext class doesn't require
a stack frame, we patched a memory leak where a StackFrame object was being
created and leaked.

Made the RegisterContext class not have a pointer to a StackFrame object as
one register context class can be used for N inlined stack frames so there is
not a 1 - 1 mapping. Updates the ExecutionContextScope part of the 
RegisterContext class to never return a stack frame to indicate this when it
is asked to recreate the execution context. Now register contexts point to the
concrete frame using a concrete frame index. Concrete frames are all of the
frames that are actually formed on the stack of a thread. These concrete frames
can be turned into one or more user visible frames due to inlining. Each 
inlined stack frame has the exact same register context (shared via shared
pointers) as any parent inlined stack frames all the way up to the concrete 
frame itself.

So now the stack frames and the register contexts should behave much better.

llvm-svn: 122976

1 files changed, 3 insertions, 3 deletions

diff --git a/lldb/source/API/SBFrame.cpp b/lldb/source/API/SBFrame.cpp
index 6c1cf09a693..1f20e10e24f 100644
--- a/lldb/source/API/SBFrame.cpp
+++ b/lldb/source/API/SBFrame.cpp
@@ -426,7 +426,7 @@ SBFrame::FindValue (const char *name, ValueType value_type)
 
         case eValueTypeRegister:            // stack frame register value
             {
-                RegisterContext *reg_ctx = m_opaque_sp->GetRegisterContext();
+                RegisterContextSP reg_ctx (m_opaque_sp->GetRegisterContext());
                 if (reg_ctx)
                 {
                     const uint32_t num_regs = reg_ctx->GetRegisterCount();
@@ -446,7 +446,7 @@ SBFrame::FindValue (const char *name, ValueType value_type)
 
         case eValueTypeRegisterSet:         // A collection of stack frame register values
             {
-                RegisterContext *reg_ctx = m_opaque_sp->GetRegisterContext();
+                RegisterContextSP reg_ctx (m_opaque_sp->GetRegisterContext());
                 if (reg_ctx)
                 {
                     const uint32_t num_sets = reg_ctx->GetRegisterSetCount();
@@ -640,7 +640,7 @@ SBFrame::GetRegisters ()
     if (m_opaque_sp)
     {
         Mutex::Locker api_locker (m_opaque_sp->GetThread().GetProcess().GetTarget().GetAPIMutex());
-        RegisterContext *reg_ctx = m_opaque_sp->GetRegisterContext();
+        RegisterContextSP reg_ctx (m_opaque_sp->GetRegisterContext());
         if (reg_ctx)
         {
             const uint32_t num_sets = reg_ctx->GetRegisterSetCount();