1 files changed, 49 insertions, 5 deletions

diff --git a/contrib/llvm/tools/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp b/contrib/llvm/tools/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
index 552ae501bd21..a3a7002ea099 100644
--- a/contrib/llvm/tools/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
+++ b/contrib/llvm/tools/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
@@ -26,8 +26,21 @@ using namespace lldb_private;
 UnwindLLDB::UnwindLLDB (Thread &thread) :
     Unwind (thread),
     m_frames(),
-    m_unwind_complete(false)
+    m_unwind_complete(false),
+    m_user_supplied_trap_handler_functions()
 {
+    ProcessSP process_sp(thread.GetProcess());
+    if (process_sp)
+    {
+        Args args;
+        process_sp->GetTarget().GetUserSpecifiedTrapHandlerNames (args);
+        size_t count = args.GetArgumentCount();
+        for (size_t i = 0; i < count; i++)
+        {
+            const char *func_name = args.GetArgumentAtIndex(i);
+            m_user_supplied_trap_handler_functions.push_back (ConstString (func_name));
+        }
+    }
 }
 
 uint32_t
@@ -95,7 +108,13 @@ UnwindLLDB::AddFirstFrame ()
     first_cursor_sp->reg_ctx_lldb_sp = reg_ctx_sp;
     m_frames.push_back (first_cursor_sp);
     return true;
+
 unwind_done:
+    Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+    if (log)
+    {
+        log->Printf ("th%d Unwind of this thread is complete.", m_thread.GetIndexID());
+    }
     m_unwind_complete = true;
     return false;
 }
@@ -138,7 +157,12 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
     }
 
     if (reg_ctx_sp.get() == NULL)
+    {
+        if (log)
+            log->Printf ("%*sFrame %d did not get a RegisterContext, stopping.",
+                         cur_idx < 100 ? cur_idx : 100, "", cur_idx);
         goto unwind_done;
+    }
 
     if (!reg_ctx_sp->IsValid())
     {
@@ -160,12 +184,18 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
     }
     if (abi && !abi->CallFrameAddressIsValid(cursor_sp->cfa))
     {
-        if (log)
+        // On Mac OS X, the _sigtramp asynchronous signal trampoline frame may not have
+        // its (constructed) CFA aligned correctly -- don't do the abi alignment check for
+        // these.
+        if (reg_ctx_sp->IsTrapHandlerFrame() == false)
         {
-            log->Printf("%*sFrame %d did not get a valid CFA for this frame, stopping stack walk",
-                        cur_idx < 100 ? cur_idx : 100, "", cur_idx);
+            if (log)
+            {
+                log->Printf("%*sFrame %d did not get a valid CFA for this frame, stopping stack walk",
+                            cur_idx < 100 ? cur_idx : 100, "", cur_idx);
+            }
+            goto unwind_done;
         }
-        goto unwind_done;
     }
     if (!reg_ctx_sp->ReadPC (cursor_sp->start_pc))
     {
@@ -185,12 +215,26 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
         }
         goto unwind_done;
     }
+    if (!m_frames.empty())
+    {
+        // Infinite loop where the current cursor is the same as the previous one...
+        if (m_frames.back()->start_pc == cursor_sp->start_pc && m_frames.back()->cfa == cursor_sp->cfa)
+        {
+            if (log)
+                log->Printf ("th%d pc of this frame is the same as the previous frame and CFAs for both frames are identical -- stopping unwind", m_thread.GetIndexID());
+            goto unwind_done; 
+        }
+    }
 
     cursor_sp->reg_ctx_lldb_sp = reg_ctx_sp;
     m_frames.push_back (cursor_sp);
     return true;
     
 unwind_done:
+    if (log)
+    {
+        log->Printf ("th%d Unwind of this thread is complete.", m_thread.GetIndexID());
+    }
     m_unwind_complete = true;
     return false;
 }