diff options
Diffstat (limited to 'source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp')
| -rw-r--r-- | source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp | 45 |
1 files changed, 38 insertions, 7 deletions
diff --git a/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp b/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp index 7e4c696..76f0b48 100644 --- a/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp +++ b/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp @@ -155,6 +155,7 @@ private: bool mov_reg_to_local_stack_frame_p (int& regno, int& fp_offset); bool ret_pattern_p (); bool pop_rbp_pattern_p (); + bool leave_pattern_p (); bool call_next_insn_pattern_p(); uint32_t extract_4 (uint8_t *b); bool machine_regno_to_lldb_regno (int machine_regno, uint32_t& lldb_regno); @@ -492,6 +493,14 @@ AssemblyParse_x86::pop_rbp_pattern_p () return (*p == 0x5d); } +// leave [0xc9] +bool +AssemblyParse_x86::leave_pattern_p () +{ + uint8_t *p = m_cur_insn_bytes; + return (*p == 0xc9); +} + // call $0 [0xe8 0x0 0x0 0x0 0x0] bool AssemblyParse_x86::call_next_insn_pattern_p () @@ -780,8 +789,7 @@ AssemblyParse_x86::get_non_call_site_unwind_plan (UnwindPlan &unwind_plan) if (machine_regno == (int)m_machine_fp_regnum) { - row->GetCFAValue().SetIsRegisterPlusOffset (m_lldb_sp_regnum, - row->GetCFAValue().GetOffset()); + row->GetCFAValue().SetIsRegisterPlusOffset (m_lldb_sp_regnum, row->GetCFAValue().GetOffset()); } in_epilogue = true; @@ -792,12 +800,35 @@ AssemblyParse_x86::get_non_call_site_unwind_plan (UnwindPlan &unwind_plan) // we need to add a new row of instructions. if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetIsRegisterPlusOffset(m_lldb_sp_regnum, - current_sp_bytes_offset_from_cfa); + row->GetCFAValue().SetIsRegisterPlusOffset (m_lldb_sp_regnum, current_sp_bytes_offset_from_cfa); row_updated = true; } } + // The LEAVE instruction moves the value from rbp into rsp and pops + // a value off the stack into rbp (restoring the caller's rbp value). + // It is the opposite of ENTER, or 'push rbp, mov rsp rbp'. + else if (leave_pattern_p ()) + { + // We're going to copy the value in rbp into rsp, so re-set the sp offset + // based on the CFAValue. Also, adjust it to recognize that we're popping + // the saved rbp value off the stack. + current_sp_bytes_offset_from_cfa = row->GetCFAValue().GetOffset(); + current_sp_bytes_offset_from_cfa -= m_wordsize; + row->GetCFAValue().SetOffset (current_sp_bytes_offset_from_cfa); + + // rbp is restored to the caller's value + saved_registers[m_machine_fp_regnum] = false; + row->RemoveRegisterInfo (m_lldb_fp_regnum); + + // cfa is now in terms of rsp again. + row->GetCFAValue().SetIsRegisterPlusOffset (m_lldb_sp_regnum, row->GetCFAValue().GetOffset()); + row->GetCFAValue().SetOffset (current_sp_bytes_offset_from_cfa); + + in_epilogue = true; + row_updated = true; + } + else if (mov_reg_to_local_stack_frame_p (machine_regno, stack_offset) && nonvolatile_reg_p (machine_regno) && machine_regno_to_lldb_regno (machine_regno, lldb_regno) @@ -1137,15 +1168,15 @@ AssemblyParse_x86::augment_unwind_plan_from_call_site (AddressRange& func, Unwin // The only case we care about is epilogue: // [0x5d] pop %rbp/%ebp // => [0xc3] ret - if (pop_rbp_pattern_p ()) + if (pop_rbp_pattern_p () || leave_pattern_p ()) { if (target->ReadMemory (m_cur_insn, prefer_file_cache, m_cur_insn_bytes, 1, error) != static_cast<size_t>(-1) && ret_pattern_p ()) { row->SetOffset (offset); - row->GetCFAValue().SetIsRegisterPlusOffset ( - first_row->GetCFAValue().GetRegisterNumber(), m_wordsize); + row->GetCFAValue().SetIsRegisterPlusOffset (first_row->GetCFAValue().GetRegisterNumber(), + m_wordsize); UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); unwind_plan.InsertRow (new_row); |
