Author: labath Date: Mon Apr 27 04:21:14 2015 New Revision: 235852 URL: http://llvm.org/viewvc/llvm-project?rev=235852&view=rev Log: Fix register read callback in linux-arm single stepping
The previous read callback always read the value of the register what caused problems when the emulator wrote some value into a register and then expected to read the same value back. This CL add a register value cache into the callbacks to return the correct value after a register write also. Test Plan: Stepping over BL/BLX instruction works on android-arm if the instruction set isn't change (other, unrelated patch will come for the case when we move to an other instruction set) Reviewers: omjavaid, sas, clayborg Reviewed By: clayborg Subscribers: labath, tberghammer, rengolin, aemerson, lldb-commits Differential Revision: http://reviews.llvm.org/D9187 From: Tamas Berghammer <tbergham...@google.com> Modified: lldb/trunk/source/Plugins/Process/Linux/NativeProcessLinux.cpp Modified: lldb/trunk/source/Plugins/Process/Linux/NativeProcessLinux.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Process/Linux/NativeProcessLinux.cpp?rev=235852&r1=235851&r2=235852&view=diff ============================================================================== --- lldb/trunk/source/Plugins/Process/Linux/NativeProcessLinux.cpp (original) +++ lldb/trunk/source/Plugins/Process/Linux/NativeProcessLinux.cpp Mon Apr 27 04:21:14 2015 @@ -2738,10 +2738,11 @@ struct EmulatorBaton { NativeProcessLinux* m_process; NativeRegisterContext* m_reg_context; - RegisterValue m_pc; - RegisterValue m_flags; - EmulatorBaton(NativeProcessLinux* process, NativeRegisterContext* reg_context) : + // eRegisterKindDWARF -> RegsiterValue + std::unordered_map<uint32_t, RegisterValue> m_register_values; + + EmulatorBaton(NativeProcessLinux* process, NativeRegisterContext* reg_context) : m_process(process), m_reg_context(reg_context) {} }; @@ -2770,6 +2771,13 @@ ReadRegisterCallback (EmulateInstruction { EmulatorBaton* emulator_baton = static_cast<EmulatorBaton*>(baton); + auto it = emulator_baton->m_register_values.find(reg_info->kinds[eRegisterKindDWARF]); + if (it != emulator_baton->m_register_values.end()) + { + reg_value = it->second; + return true; + } + // The emulator only fill in the dwarf regsiter numbers (and in some case // the generic register numbers). Get the full register info from the // register context based on the dwarf register numbers. @@ -2777,7 +2785,12 @@ ReadRegisterCallback (EmulateInstruction eRegisterKindDWARF, reg_info->kinds[eRegisterKindDWARF]); Error error = emulator_baton->m_reg_context->ReadRegister(full_reg_info, reg_value); - return error.Success(); + if (error.Success()) + { + emulator_baton->m_register_values[reg_info->kinds[eRegisterKindDWARF]] = reg_value; + return true; + } + return false; } static bool @@ -2788,17 +2801,7 @@ WriteRegisterCallback (EmulateInstructio const RegisterValue ®_value) { EmulatorBaton* emulator_baton = static_cast<EmulatorBaton*>(baton); - - switch (reg_info->kinds[eRegisterKindGeneric]) - { - case LLDB_REGNUM_GENERIC_PC: - emulator_baton->m_pc = reg_value; - break; - case LLDB_REGNUM_GENERIC_FLAGS: - emulator_baton->m_flags = reg_value; - break; - } - + emulator_baton->m_register_values[reg_info->kinds[eRegisterKindDWARF]] = reg_value; return true; } @@ -2843,17 +2846,27 @@ NativeProcessLinux::SetupSoftwareSingleS if (!emulator_ap->ReadInstruction()) return Error("Read instruction failed!"); + bool emulation_result = emulator_ap->EvaluateInstruction(eEmulateInstructionOptionAutoAdvancePC); + + const RegisterInfo* reg_info_pc = register_context_sp->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC); + const RegisterInfo* reg_info_flags = register_context_sp->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FLAGS); + + auto pc_it = baton.m_register_values.find(reg_info_pc->kinds[eRegisterKindDWARF]); + auto flags_it = baton.m_register_values.find(reg_info_flags->kinds[eRegisterKindDWARF]); + lldb::addr_t next_pc; lldb::addr_t next_flags; - if (emulator_ap->EvaluateInstruction(eEmulateInstructionOptionAutoAdvancePC)) + if (emulation_result) { - next_pc = baton.m_pc.GetAsUInt64(); - if (baton.m_flags.GetType() != RegisterValue::eTypeInvalid) - next_flags = baton.m_flags.GetAsUInt32(); + assert(pc_it != baton.m_register_values.end() && "Emulation was successfull but PC wasn't updated"); + next_pc = pc_it->second.GetAsUInt64(); + + if (flags_it != baton.m_register_values.end()) + next_flags = flags_it->second.GetAsUInt64(); else next_flags = ReadFlags (register_context_sp.get()); } - else if (baton.m_pc.GetType() == RegisterValue::eTypeInvalid) + else if (pc_it == baton.m_register_values.end()) { // Emulate instruction failed and it haven't changed PC. Advance PC // with the size of the current opcode because the emulation of all @@ -2889,7 +2902,6 @@ NativeProcessLinux::SetupSoftwareSingleS error = SetSoftwareBreakpoint(next_pc, 0); } - if (error.Fail()) return error; _______________________________________________ lldb-commits mailing list lldb-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/lldb-commits
