From d59fd74eec765cba98e815b7bf900fee0ce1ce44 Mon Sep 17 00:00:00 2001 From: Jason Molenda <jmolenda@apple.com> Date: Thu, 12 Jul 2012 23:43:02 +0000 Subject: [PATCH] When parsing the epilogue of a thumbv2 function, when we see the frame pointer overwritten with the caller's fp value, return to expressing the CFA in terms of the stack pointer. <rdar://problem/11855862> llvm-svn: 160150 --- .../InstEmulation/UnwindAssemblyInstEmulation.cpp | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp b/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp index 6d2b0a54b6a6..58416dd5ea34 100644 --- a/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp +++ b/lldb/source/Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.cpp @@ -490,6 +490,20 @@ UnwindAssemblyInstEmulation::WriteRegister (EmulateInstruction *instruction, { m_curr_row.SetRegisterLocationToSame (reg_num, must_replace); } + // if we just restored the caller's reg value in the reg we were using for the frame pointer, + // change the CFA to be in terms of the stack pointer again. + if (m_fp_is_cfa && reg_num == m_cfa_reg_info.kinds[m_unwind_plan_ptr->GetRegisterKind()]) + { + m_fp_is_cfa = false; + m_inst_emulator_ap->GetRegisterInfo (m_unwind_plan_ptr->GetRegisterKind(), + m_unwind_plan_ptr->GetInitialCFARegister(), + m_cfa_reg_info); + m_curr_row.SetCFARegister(m_cfa_reg_info.kinds[m_unwind_plan_ptr->GetRegisterKind()]); + if (log && log->GetVerbose()) + { + log->Printf("UnwindAssemblyInstEmulation::WriteRegister - CFA is expressed in terms of %s again", m_cfa_reg_info.name); + } + } } break;