diff --git a/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp b/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp index 4f9ae3ea69de..536b08460b95 100644 --- a/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp +++ b/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp @@ -1661,6 +1661,55 @@ EmulateInstructionARM::EmulateAddRdnRm (ARMEncoding encoding) return true; } +bool +EmulateInstructionARM::EmulateCmpRnImm (ARMEncoding encoding) +{ +#if 0 + // ARM pseudo code... + if ConditionPassed() then + EncodingSpecificOperations(); + (result, carry, overflow) = AddWithCarry(R[n], NOT(imm32), '1'); + APSR.N = result<31>; + APSR.Z = IsZeroBit(result); + APSR.C = carry; + APSR.V = overflow; +#endif + + bool success = false; + const uint32_t opcode = OpcodeAsUnsigned (&success); + if (!success) + return false; + + uint32_t Rn; // the first operand + uint32_t imm32; // the immediate value to be compared with + switch (encoding) { + case eEncodingT1: + Rn = Bits32(opcode, 10, 8); + imm32 = Bits32(opcode, 7, 0); + break; + default: + return false; + } + // Read the register value from the operand register Rn. + uint32_t reg_val = ReadRegisterUnsigned(eRegisterKindDWARF, dwarf_r0 + Rn, 0, &success); + if (!success) + return false; + + EmulateInstruction::Context context = { EmulateInstruction::eContextImmediate, 0, 0, 0}; + AddWithCarryResult res = AddWithCarry(reg_val, ~imm32, 1); + m_new_inst_cpsr = m_inst_cpsr; + SetBit32(m_new_inst_cpsr, CPSR_N, Bit32(res.result, CPSR_N)); + SetBit32(m_new_inst_cpsr, CPSR_Z, res.result == 0 ? 1 : 0); + SetBit32(m_new_inst_cpsr, CPSR_C, res.carry_out); + SetBit32(m_new_inst_cpsr, CPSR_V, res.overflow); + if (m_new_inst_cpsr != m_inst_cpsr) + { + if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FLAGS, m_new_inst_cpsr)) + return false; + } + return true; +} + // LDM loads multiple registers from consecutive memory locations, using an // address from a base register. Optionally the addres just above the highest of those locations // can be written back to the base register. @@ -2288,6 +2337,8 @@ EmulateInstructionARM::GetThumbOpcodeForInstruction (const uint32_t opcode) { 0xffffff00, 0x00004600, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateMovRdRm, "mov , "}, // move from low register to low register { 0xffffffc0, 0x00000000, ARMvAll, eEncodingT2, eSize16, &EmulateInstructionARM::EmulateMovRdRm, "movs , "}, + // compare a register with immediate + { 0xfffff800, 0x00002800, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateCmpRnImm, "cmp , #imm8"}, //---------------------------------------------------------------------- // Load instructions diff --git a/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.h b/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.h index 55e750b5a1b3..9e2c9b6c00ca 100644 --- a/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.h +++ b/lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.h @@ -271,6 +271,13 @@ protected: bool EmulateAddRdnRm (ARMEncoding encoding); + // MOV (register) + bool + EmulateMovRdRm (ARMEncoding encoding); + + bool + EmulateCmpRnImm (ARMEncoding encoding); + bool EmulateLDM (ARMEncoding encoding); @@ -283,10 +290,6 @@ protected: bool EmulateLDRRtRnImm (ARMEncoding encoding); - // MOV (register) - bool - EmulateMovRdRm (ARMEncoding encoding); - uint32_t m_arm_isa; Mode m_inst_mode; uint32_t m_inst_cpsr;