diff options
Diffstat (limited to 'llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp')
| -rw-r--r-- | llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp b/llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp index ae262abe6a8..ad9308321fd 100644 --- a/llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp +++ b/llvm/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp @@ -224,6 +224,26 @@ static void LowerUnaryToTwoAddr(MCInst &OutMI, unsigned NewOpc) { OutMI.addOperand(OutMI.getOperand(0)); } +/// \brief Simplify FOO $imm, %{al,ax,eax,rax} to FOO $imm, for instruction with +/// a short fixed-register form. +static void SimplifyShortImmForm(MCInst &Inst, unsigned Opcode) { + unsigned ImmOp = Inst.getNumOperands() - 1; + assert(Inst.getOperand(0).isReg() && Inst.getOperand(ImmOp).isImm() && + ((Inst.getNumOperands() == 3 && Inst.getOperand(1).isReg() && + Inst.getOperand(0).getReg() == Inst.getOperand(1).getReg()) || + Inst.getNumOperands() == 2) && "Unexpected instruction!"); + + // Check whether the destination register can be fixed. + unsigned Reg = Inst.getOperand(0).getReg(); + if (Reg != X86::AL && Reg != X86::AX && Reg != X86::EAX && Reg != X86::RAX) + return; + + // If so, rewrite the instruction. + MCInst New; + New.setOpcode(Opcode); + New.addOperand(Inst.getOperand(ImmOp)); + Inst = New; +} void X86MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const { OutMI.setOpcode(MI->getOpcode()); @@ -332,6 +352,54 @@ void X86MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const { case X86::JGE_4: OutMI.setOpcode(X86::JGE_1); break; case X86::JLE_4: OutMI.setOpcode(X86::JLE_1); break; case X86::JG_4: OutMI.setOpcode(X86::JG_1); break; + + // We don't currently select the correct instruction form for instructions + // which have a short %eax, etc. form. Handle this by custom lowering, for + // now. + // + // Note, we are currently not handling the following instructions: + // MOV8ao8, MOV8o8a + // MOV16ao16, MOV16o16a + // MOV32ao32, MOV32o32a + // MOV64ao64, MOV64ao8 + // MOV64o64a, MOV64o8a + // XCHG16ar, XCHG32ar, XCHG64ar + case X86::ADC8ri: SimplifyShortImmForm(OutMI, X86::ADC8i8); break; + case X86::ADC16ri: SimplifyShortImmForm(OutMI, X86::ADC16i16); break; + case X86::ADC32ri: SimplifyShortImmForm(OutMI, X86::ADC32i32); break; + case X86::ADC64ri32: SimplifyShortImmForm(OutMI, X86::ADC64i32); break; + case X86::ADD8ri: SimplifyShortImmForm(OutMI, X86::ADD8i8); break; + case X86::ADD16ri: SimplifyShortImmForm(OutMI, X86::ADD16i16); break; + case X86::ADD32ri: SimplifyShortImmForm(OutMI, X86::ADD32i32); break; + case X86::ADD64ri32: SimplifyShortImmForm(OutMI, X86::ADD64i32); break; + case X86::AND8ri: SimplifyShortImmForm(OutMI, X86::AND8i8); break; + case X86::AND16ri: SimplifyShortImmForm(OutMI, X86::AND16i16); break; + case X86::AND32ri: SimplifyShortImmForm(OutMI, X86::AND32i32); break; + case X86::AND64ri32: SimplifyShortImmForm(OutMI, X86::AND64i32); break; + case X86::CMP8ri: SimplifyShortImmForm(OutMI, X86::CMP8i8); break; + case X86::CMP16ri: SimplifyShortImmForm(OutMI, X86::CMP16i16); break; + case X86::CMP32ri: SimplifyShortImmForm(OutMI, X86::CMP32i32); break; + case X86::CMP64ri32: SimplifyShortImmForm(OutMI, X86::CMP64i32); break; + case X86::OR8ri: SimplifyShortImmForm(OutMI, X86::OR8i8); break; + case X86::OR16ri: SimplifyShortImmForm(OutMI, X86::OR16i16); break; + case X86::OR32ri: SimplifyShortImmForm(OutMI, X86::OR32i32); break; + case X86::OR64ri32: SimplifyShortImmForm(OutMI, X86::OR64i32); break; + case X86::SBB8ri: SimplifyShortImmForm(OutMI, X86::SBB8i8); break; + case X86::SBB16ri: SimplifyShortImmForm(OutMI, X86::SBB16i16); break; + case X86::SBB32ri: SimplifyShortImmForm(OutMI, X86::SBB32i32); break; + case X86::SBB64ri32: SimplifyShortImmForm(OutMI, X86::SBB64i32); break; + case X86::SUB8ri: SimplifyShortImmForm(OutMI, X86::SUB8i8); break; + case X86::SUB16ri: SimplifyShortImmForm(OutMI, X86::SUB16i16); break; + case X86::SUB32ri: SimplifyShortImmForm(OutMI, X86::SUB32i32); break; + case X86::SUB64ri32: SimplifyShortImmForm(OutMI, X86::SUB64i32); break; + case X86::TEST8ri: SimplifyShortImmForm(OutMI, X86::TEST8i8); break; + case X86::TEST16ri: SimplifyShortImmForm(OutMI, X86::TEST16i16); break; + case X86::TEST32ri: SimplifyShortImmForm(OutMI, X86::TEST32i32); break; + case X86::TEST64ri32: SimplifyShortImmForm(OutMI, X86::TEST64i32); break; + case X86::XOR8ri: SimplifyShortImmForm(OutMI, X86::XOR8i8); break; + case X86::XOR16ri: SimplifyShortImmForm(OutMI, X86::XOR16i16); break; + case X86::XOR32ri: SimplifyShortImmForm(OutMI, X86::XOR32i32); break; + case X86::XOR64ri32: SimplifyShortImmForm(OutMI, X86::XOR64i32); break; } } |

