vendor/lldb/lldb-trunk-r257626

3 files changed, 33 insertions, 5 deletions

diff --git a/source/Plugins/Process/Utility/InferiorCallPOSIX.cpp b/source/Plugins/Process/Utility/InferiorCallPOSIX.cpp
index bd3978cc0ab4..ebeba8c46a74 100644
--- a/source/Plugins/Process/Utility/InferiorCallPOSIX.cpp
+++ b/source/Plugins/Process/Utility/InferiorCallPOSIX.cpp
@@ -72,6 +72,7 @@ lldb_private::InferiorCallMmap (Process *process,
             options.SetTryAllThreads(true);
             options.SetDebug (false);
             options.SetTimeoutUsec(500000);
+            options.SetTrapExceptions(false);
 
             addr_t prot_arg, flags_arg = 0;
             if (prot == eMmapProtNone)
@@ -172,6 +173,7 @@ lldb_private::InferiorCallMunmap (Process *process,
             options.SetTryAllThreads(true);
             options.SetDebug (false);
             options.SetTimeoutUsec(500000);
+            options.SetTrapExceptions(false);
            
             AddressRange munmap_range;
             if (sc.GetAddressRange(range_scope, 0, use_inline_block_range, munmap_range))
@@ -214,7 +216,8 @@ lldb_private::InferiorCallMunmap (Process *process,
 bool
 lldb_private::InferiorCall (Process *process,
                             const Address *address,
-                            addr_t &returned_func)
+                            addr_t &returned_func,
+                            bool trap_exceptions)
 {
     Thread *thread = process->GetThreadList().GetSelectedThread().get();
     if (thread == NULL || address == NULL)
@@ -227,6 +230,7 @@ lldb_private::InferiorCall (Process *process,
     options.SetTryAllThreads(true);
     options.SetDebug (false);
     options.SetTimeoutUsec(500000);
+    options.SetTrapExceptions(trap_exceptions);
 
     ClangASTContext *clang_ast_context = process->GetTarget().GetScratchClangASTContext();
     CompilerType clang_void_ptr_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType();
diff --git a/source/Plugins/Process/Utility/InferiorCallPOSIX.h b/source/Plugins/Process/Utility/InferiorCallPOSIX.h
index e56e95c43773..d10e8490d809 100644
--- a/source/Plugins/Process/Utility/InferiorCallPOSIX.h
+++ b/source/Plugins/Process/Utility/InferiorCallPOSIX.h
@@ -31,7 +31,8 @@ bool InferiorCallMmap(Process *proc, lldb::addr_t &allocated_addr,
 
 bool InferiorCallMunmap(Process *proc, lldb::addr_t addr, lldb::addr_t length);
 
-bool InferiorCall(Process *proc, const Address *address, lldb::addr_t &returned_func);
+bool InferiorCall(Process *proc, const Address *address, lldb::addr_t &returned_func,
+                  bool trap_exceptions = false);
 
 }   // namespace lldb_private
 
diff --git a/source/Plugins/Process/Utility/RegisterContextLLDB.cpp b/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
index 278a1d5dabf6..efda0edb70c9 100644
--- a/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
+++ b/source/Plugins/Process/Utility/RegisterContextLLDB.cpp
@@ -265,9 +265,32 @@ RegisterContextLLDB::InitializeZerothFrame()
 
     if (!ReadCFAValueForRow (row_register_kind, active_row, m_cfa))
     {
-        UnwindLogMsg ("could not read CFA register for this frame.");
-        m_frame_type = eNotAValidFrame;
-        return;
+        // Try the fall back unwind plan since the
+        // full unwind plan failed.
+        FuncUnwindersSP func_unwinders_sp;
+        UnwindPlanSP call_site_unwind_plan;
+        bool cfa_status = false;
+
+        if (m_sym_ctx_valid)
+        {
+            func_unwinders_sp = pc_module_sp->GetObjectFile()->GetUnwindTable().GetFuncUnwindersContainingAddress (m_current_pc, m_sym_ctx);
+        }
+
+        if(func_unwinders_sp.get() != nullptr)
+            call_site_unwind_plan = func_unwinders_sp->GetUnwindPlanAtCallSite(process->GetTarget(), m_current_offset_backed_up_one);
+
+        if (call_site_unwind_plan.get() != nullptr)
+        {
+            m_fallback_unwind_plan_sp = call_site_unwind_plan;
+            if(TryFallbackUnwindPlan())
+                cfa_status = true;
+        }
+        if (!cfa_status)
+        {
+            UnwindLogMsg ("could not read CFA value for first frame.");
+            m_frame_type = eNotAValidFrame;
+            return;
+        }
     }
 
     UnwindLogMsg ("initialized frame current pc is 0x%" PRIx64 " cfa is 0x%" PRIx64 " using %s UnwindPlan",