Fixed a bug where CFI data would become corrupted when using remember/restore state instructions.

This would prevent system calls on Linux from being able to backtrace correctly.

llvm-svn: 190642

1 files changed, 5 insertions, 2 deletions

diff --git a/lldb/source/Symbol/DWARFCallFrameInfo.cpp b/lldb/source/Symbol/DWARFCallFrameInfo.cpp
index 5caf8007485..d3d96289669 100644
--- a/lldb/source/Symbol/DWARFCallFrameInfo.cpp
+++ b/lldb/source/Symbol/DWARFCallFrameInfo.cpp
@@ -444,6 +444,8 @@ DWARFCallFrameInfo::FDEToUnwindPlan (dw_offset_t dwarf_offset, Address startaddr
     unwind_plan.SetRegisterKind (m_reg_kind);
     unwind_plan.SetReturnAddressRegister (cie->return_addr_reg_num);
 
+    std::vector<UnwindPlan::RowSP> stack;
+
     UnwindPlan::Row::RegisterLocation reg_location;
     while (m_cfi_data.ValidOffset(offset) && offset < end_offset)
     {
@@ -629,7 +631,7 @@ DWARFCallFrameInfo::FDEToUnwindPlan (dw_offset_t dwarf_offset, Address startaddr
                         // the stack and place them in the current row. (This operation is
                         // useful for compilers that move epilogue code into the body of a
                         // function.)
-                        unwind_plan.AppendRow (row);
+                        stack.push_back (row);
                         UnwindPlan::Row *newrow = new UnwindPlan::Row;
                         *newrow = *row.get();
                         row.reset (newrow);
@@ -645,7 +647,8 @@ DWARFCallFrameInfo::FDEToUnwindPlan (dw_offset_t dwarf_offset, Address startaddr
                     // useful for compilers that move epilogue code into the body of a
                     // function.)
                     {
-                        row = unwind_plan.GetRowAtIndex(unwind_plan.GetRowCount() - 1);
+                        row = stack.back ();
+                        stack.pop_back ();
                     }
                     break;