Index: llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp =================================================================== --- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp +++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp @@ -5467,14 +5467,14 @@ CanAcceptPredicationCode = true; } -// \brief Some Thumb1 instructions have two operand forms that are not +// \brief Some Thumb instructions have two operand forms that are not // available as three operand, convert to two operand form if possible. // // FIXME: We would really like to be able to tablegen'erate this. void ARMAsmParser::tryConvertingToTwoOperandForm(StringRef Mnemonic, bool CarrySetting, OperandVector &Operands) { - if (Operands.size() != 6 || !isThumbOne()) + if (Operands.size() != 6) return; ARMOperand &Op3 = static_cast(*Operands[3]); @@ -5482,7 +5482,17 @@ if (!Op3.isReg() || !Op4.isReg()) return; + // For most Thumb2 cases we just generate the 3 operand form and reduce + // it in processInstruction(), but for ADD involving PC the the 3 operand + // form won't accept PC so we do the transformation here. ARMOperand &Op5 = static_cast(*Operands[5]); + if (isThumbTwo()) { + if (Mnemonic != "add" || + !(Op3.getReg() == ARM::PC || Op4.getReg() == ARM::PC || + (Op5.isReg() && Op5.getReg() == ARM::PC))) + return; + } else if (!isThumbOne()) + return; if (!(Mnemonic == "add" || Mnemonic == "sub" || Mnemonic == "and" || Mnemonic == "eor" || Mnemonic == "lsl" || Mnemonic == "lsr" || Index: llvm/trunk/test/MC/ARM/thumb2-narrow-dp.ll =================================================================== --- llvm/trunk/test/MC/ARM/thumb2-narrow-dp.ll +++ llvm/trunk/test/MC/ARM/thumb2-narrow-dp.ll @@ -65,6 +65,10 @@ ADD r3, r3, r1 // T2 // CHECK: add r3, r1 @ encoding: [0x0b,0x44] + ADD r4, r4, pc // T2 +// CHECK: add r4, pc @ encoding: [0x7c,0x44] + ADD pc, pc, r2 // T2 +// CHECK: add pc, r2 @ encoding: [0x97,0x44] // ADD (SP plus immediate) A8.8.9 ADD sp, sp, #20 // T2