/// X86MCInstLower - This class is used to lower an MachineInstr into an MCInst.
class X86MCInstLower {
MCContext &Ctx;
- Mangler *Mang;
const MachineFunction &MF;
const TargetMachine &TM;
const MCAsmInfo &MAI;
X86AsmPrinter &AsmPrinter;
public:
- X86MCInstLower(Mangler *mang, const MachineFunction &MF,
- X86AsmPrinter &asmprinter);
+ X86MCInstLower(const MachineFunction &MF, X86AsmPrinter &asmprinter);
void Lower(const MachineInstr *MI, MCInst &OutMI) const;
private:
MachineModuleInfoMachO &getMachOMMI() const;
+ Mangler *getMang() const {
+ return AsmPrinter.Mang;
+ }
};
} // end anonymous namespace
-X86MCInstLower::X86MCInstLower(Mangler *mang, const MachineFunction &mf,
+X86MCInstLower::X86MCInstLower(const MachineFunction &mf,
X86AsmPrinter &asmprinter)
-: Ctx(mf.getContext()), Mang(mang), MF(mf), TM(mf.getTarget()),
+: Ctx(mf.getContext()), MF(mf), TM(mf.getTarget()),
MAI(*TM.getMCAsmInfo()), AsmPrinter(asmprinter) {}
MachineModuleInfoMachO &X86MCInstLower::getMachOMMI() const {
MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
isImplicitlyPrivate = true;
- Mang->getNameWithPrefix(Name, GV, isImplicitlyPrivate);
+ getMang()->getNameWithPrefix(Name, GV, isImplicitlyPrivate);
} else if (MO.isSymbol()) {
Name += MAI.getGlobalPrefix();
Name += MO.getSymbolName();
assert(MO.isGlobal() && "Extern symbol not handled yet");
StubSym =
MachineModuleInfoImpl::
- StubValueTy(Mang->getSymbol(MO.getGlobal()),
+ StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
}
return Sym;
assert(MO.isGlobal() && "Extern symbol not handled yet");
StubSym =
MachineModuleInfoImpl::
- StubValueTy(Mang->getSymbol(MO.getGlobal()),
+ StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
}
return Sym;
if (MO.isGlobal()) {
StubSym =
MachineModuleInfoImpl::
- StubValueTy(Mang->getSymbol(MO.getGlobal()),
+ StubValueTy(AsmPrinter.getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
} else {
Name.erase(Name.end()-5, Name.end());
}
-
-static void lower_subreg32(MCInst *MI, unsigned OpNo) {
- // Convert registers in the addr mode according to subreg32.
- unsigned Reg = MI->getOperand(OpNo).getReg();
- if (Reg != 0)
- MI->getOperand(OpNo).setReg(getX86SubSuperRegister(Reg, MVT::i32));
-}
-
-static void lower_lea64_32mem(MCInst *MI, unsigned OpNo) {
- // Convert registers in the addr mode according to subreg64.
- for (unsigned i = 0; i != 4; ++i) {
- if (!MI->getOperand(OpNo+i).isReg()) continue;
-
- unsigned Reg = MI->getOperand(OpNo+i).getReg();
- // LEAs can use RIP-relative addressing, and RIP has no sub/super register.
- if (Reg == 0 || Reg == X86::RIP) continue;
-
- MI->getOperand(OpNo+i).setReg(getX86SubSuperRegister(Reg, MVT::i64));
- }
-}
-
-/// LowerSubReg32_Op0 - Things like MOVZX16rr8 -> MOVZX32rr8.
-static void LowerSubReg32_Op0(MCInst &OutMI, unsigned NewOpc) {
- OutMI.setOpcode(NewOpc);
- lower_subreg32(&OutMI, 0);
-}
/// LowerUnaryToTwoAddr - R = setb -> R = sbb R, R
static void LowerUnaryToTwoAddr(MCInst &OutMI, unsigned NewOpc) {
OutMI.setOpcode(NewOpc);
Inst.addOperand(Saved);
}
+/// \brief If a movsx instruction has a shorter encoding for the used register
+/// simplify the instruction to use it instead.
+static void SimplifyMOVSX(MCInst &Inst) {
+ unsigned NewOpcode = 0;
+ unsigned Op0 = Inst.getOperand(0).getReg(), Op1 = Inst.getOperand(1).getReg();
+ switch (Inst.getOpcode()) {
+ default:
+ llvm_unreachable("Unexpected instruction!");
+ case X86::MOVSX16rr8: // movsbw %al, %ax --> cbtw
+ if (Op0 == X86::AX && Op1 == X86::AL)
+ NewOpcode = X86::CBW;
+ break;
+ case X86::MOVSX32rr16: // movswl %ax, %eax --> cwtl
+ if (Op0 == X86::EAX && Op1 == X86::AX)
+ NewOpcode = X86::CWDE;
+ break;
+ case X86::MOVSX64rr32: // movslq %eax, %rax --> cltq
+ if (Op0 == X86::RAX && Op1 == X86::EAX)
+ NewOpcode = X86::CDQE;
+ break;
+ }
+
+ if (NewOpcode != 0) {
+ Inst = MCInst();
+ Inst.setOpcode(NewOpcode);
+ }
+}
+
/// \brief Simplify things like MOV32rm to MOV32o32a.
static void SimplifyShortMoveForm(X86AsmPrinter &Printer, MCInst &Inst,
unsigned Opcode) {
// Handle a few special cases to eliminate operand modifiers.
ReSimplify:
switch (OutMI.getOpcode()) {
- case X86::LEA64_32r: // Handle 'subreg rewriting' for the lea64_32mem operand.
- lower_lea64_32mem(&OutMI, 1);
- // FALL THROUGH.
+ case X86::LEA64_32r:
case X86::LEA64r:
case X86::LEA16r:
case X86::LEA32r:
assert(OutMI.getOperand(1+X86::AddrSegmentReg).getReg() == 0 &&
"LEA has segment specified!");
break;
- case X86::MOVZX64rr32: LowerSubReg32_Op0(OutMI, X86::MOV32rr); break;
- case X86::MOVZX64rm32: LowerSubReg32_Op0(OutMI, X86::MOV32rm); break;
- case X86::MOV64ri64i32: LowerSubReg32_Op0(OutMI, X86::MOV32ri); break;
- case X86::MOVZX64rr8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rr8); break;
- case X86::MOVZX64rm8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rm8); break;
- case X86::MOVZX64rr16: LowerSubReg32_Op0(OutMI, X86::MOVZX32rr16); break;
- case X86::MOVZX64rm16: LowerSubReg32_Op0(OutMI, X86::MOVZX32rm16); break;
- case X86::MOV8r0: LowerUnaryToTwoAddr(OutMI, X86::XOR8rr); break;
case X86::MOV32r0: LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); break;
- case X86::MOV16r0:
- LowerSubReg32_Op0(OutMI, X86::MOV32r0); // MOV16r0 -> MOV32r0
- LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
- break;
- case X86::MOV64r0:
- LowerSubReg32_Op0(OutMI, X86::MOV32r0); // MOV64r0 -> MOV32r0
- LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
+ case X86::MOV32ri64:
+ OutMI.setOpcode(X86::MOV32ri);
break;
// Commute operands to get a smaller encoding by using VEX.R instead of VEX.B
case X86::XOR32ri: SimplifyShortImmForm(OutMI, X86::XOR32i32); break;
case X86::XOR64ri32: SimplifyShortImmForm(OutMI, X86::XOR64i32); break;
+ // Try to shrink some forms of movsx.
+ case X86::MOVSX16rr8:
+ case X86::MOVSX32rr16:
+ case X86::MOVSX64rr32:
+ SimplifyMOVSX(OutMI);
+ break;
+
case X86::MORESTACK_RET:
OutMI.setOpcode(X86::RET);
break;
}
void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
- X86MCInstLower MCInstLowering(Mang, *MF, *this);
+ X86MCInstLower MCInstLowering(*MF, *this);
switch (MI->getOpcode()) {
case TargetOpcode::DBG_VALUE:
- if (isVerbose() && OutStreamer.hasRawTextSupport()) {
- std::string TmpStr;
- raw_string_ostream OS(TmpStr);
- PrintDebugValueComment(MI, OS);
- OutStreamer.EmitRawText(StringRef(OS.str()));
- }
- return;
+ llvm_unreachable("Should be handled target independently");
// Emit nothing here but a comment if we can.
case X86::Int_MemBarrier:
projects / oota-llvm.git / blobdiff