X86MCInstLower.cpp revision 218893
1//===-- X86MCInstLower.cpp - Convert X86 MachineInstr to an MCInst --------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains code to lower X86 MachineInstrs to their corresponding
11// MCInst records.
12//
13//===----------------------------------------------------------------------===//
14
15#include "InstPrinter/X86ATTInstPrinter.h"
16#include "X86MCInstLower.h"
17#include "X86AsmPrinter.h"
18#include "X86COFFMachineModuleInfo.h"
19#include "X86MCAsmInfo.h"
20#include "llvm/CodeGen/MachineModuleInfoImpls.h"
21#include "llvm/MC/MCContext.h"
22#include "llvm/MC/MCExpr.h"
23#include "llvm/MC/MCInst.h"
24#include "llvm/MC/MCStreamer.h"
25#include "llvm/MC/MCSymbol.h"
26#include "llvm/Target/Mangler.h"
27#include "llvm/Support/FormattedStream.h"
28#include "llvm/ADT/SmallString.h"
29#include "llvm/Type.h"
30using namespace llvm;
31
32X86MCInstLower::X86MCInstLower(Mangler *mang, const MachineFunction &mf,
33                               X86AsmPrinter &asmprinter)
34: Ctx(mf.getContext()), Mang(mang), MF(mf), TM(mf.getTarget()),
35  MAI(*TM.getMCAsmInfo()), AsmPrinter(asmprinter) {}
36
37MachineModuleInfoMachO &X86MCInstLower::getMachOMMI() const {
38  return MF.getMMI().getObjFileInfo<MachineModuleInfoMachO>();
39}
40
41
42/// GetSymbolFromOperand - Lower an MO_GlobalAddress or MO_ExternalSymbol
43/// operand to an MCSymbol.
44MCSymbol *X86MCInstLower::
45GetSymbolFromOperand(const MachineOperand &MO) const {
46  assert((MO.isGlobal() || MO.isSymbol()) && "Isn't a symbol reference");
47
48  SmallString<128> Name;
49
50  if (!MO.isGlobal()) {
51    assert(MO.isSymbol());
52    Name += MAI.getGlobalPrefix();
53    Name += MO.getSymbolName();
54  } else {
55    const GlobalValue *GV = MO.getGlobal();
56    bool isImplicitlyPrivate = false;
57    if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB ||
58        MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
59        MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
60        MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
61      isImplicitlyPrivate = true;
62
63    Mang->getNameWithPrefix(Name, GV, isImplicitlyPrivate);
64  }
65
66  // If the target flags on the operand changes the name of the symbol, do that
67  // before we return the symbol.
68  switch (MO.getTargetFlags()) {
69  default: break;
70  case X86II::MO_DLLIMPORT: {
71    // Handle dllimport linkage.
72    const char *Prefix = "__imp_";
73    Name.insert(Name.begin(), Prefix, Prefix+strlen(Prefix));
74    break;
75  }
76  case X86II::MO_DARWIN_NONLAZY:
77  case X86II::MO_DARWIN_NONLAZY_PIC_BASE: {
78    Name += "$non_lazy_ptr";
79    MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
80
81    MachineModuleInfoImpl::StubValueTy &StubSym =
82      getMachOMMI().getGVStubEntry(Sym);
83    if (StubSym.getPointer() == 0) {
84      assert(MO.isGlobal() && "Extern symbol not handled yet");
85      StubSym =
86        MachineModuleInfoImpl::
87        StubValueTy(Mang->getSymbol(MO.getGlobal()),
88                    !MO.getGlobal()->hasInternalLinkage());
89    }
90    return Sym;
91  }
92  case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: {
93    Name += "$non_lazy_ptr";
94    MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
95    MachineModuleInfoImpl::StubValueTy &StubSym =
96      getMachOMMI().getHiddenGVStubEntry(Sym);
97    if (StubSym.getPointer() == 0) {
98      assert(MO.isGlobal() && "Extern symbol not handled yet");
99      StubSym =
100        MachineModuleInfoImpl::
101        StubValueTy(Mang->getSymbol(MO.getGlobal()),
102                    !MO.getGlobal()->hasInternalLinkage());
103    }
104    return Sym;
105  }
106  case X86II::MO_DARWIN_STUB: {
107    Name += "$stub";
108    MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
109    MachineModuleInfoImpl::StubValueTy &StubSym =
110      getMachOMMI().getFnStubEntry(Sym);
111    if (StubSym.getPointer())
112      return Sym;
113
114    if (MO.isGlobal()) {
115      StubSym =
116        MachineModuleInfoImpl::
117        StubValueTy(Mang->getSymbol(MO.getGlobal()),
118                    !MO.getGlobal()->hasInternalLinkage());
119    } else {
120      Name.erase(Name.end()-5, Name.end());
121      StubSym =
122        MachineModuleInfoImpl::
123        StubValueTy(Ctx.GetOrCreateSymbol(Name.str()), false);
124    }
125    return Sym;
126  }
127  }
128
129  return Ctx.GetOrCreateSymbol(Name.str());
130}
131
132MCOperand X86MCInstLower::LowerSymbolOperand(const MachineOperand &MO,
133                                             MCSymbol *Sym) const {
134  // FIXME: We would like an efficient form for this, so we don't have to do a
135  // lot of extra uniquing.
136  const MCExpr *Expr = 0;
137  MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
138
139  switch (MO.getTargetFlags()) {
140  default: llvm_unreachable("Unknown target flag on GV operand");
141  case X86II::MO_NO_FLAG:    // No flag.
142  // These affect the name of the symbol, not any suffix.
143  case X86II::MO_DARWIN_NONLAZY:
144  case X86II::MO_DLLIMPORT:
145  case X86II::MO_DARWIN_STUB:
146    break;
147
148  case X86II::MO_TLVP:      RefKind = MCSymbolRefExpr::VK_TLVP; break;
149  case X86II::MO_TLVP_PIC_BASE:
150    Expr = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_TLVP, Ctx);
151    // Subtract the pic base.
152    Expr = MCBinaryExpr::CreateSub(Expr,
153                                  MCSymbolRefExpr::Create(MF.getPICBaseSymbol(),
154                                                           Ctx),
155                                   Ctx);
156    break;
157  case X86II::MO_TLSGD:     RefKind = MCSymbolRefExpr::VK_TLSGD; break;
158  case X86II::MO_GOTTPOFF:  RefKind = MCSymbolRefExpr::VK_GOTTPOFF; break;
159  case X86II::MO_INDNTPOFF: RefKind = MCSymbolRefExpr::VK_INDNTPOFF; break;
160  case X86II::MO_TPOFF:     RefKind = MCSymbolRefExpr::VK_TPOFF; break;
161  case X86II::MO_NTPOFF:    RefKind = MCSymbolRefExpr::VK_NTPOFF; break;
162  case X86II::MO_GOTPCREL:  RefKind = MCSymbolRefExpr::VK_GOTPCREL; break;
163  case X86II::MO_GOT:       RefKind = MCSymbolRefExpr::VK_GOT; break;
164  case X86II::MO_GOTOFF:    RefKind = MCSymbolRefExpr::VK_GOTOFF; break;
165  case X86II::MO_PLT:       RefKind = MCSymbolRefExpr::VK_PLT; break;
166  case X86II::MO_PIC_BASE_OFFSET:
167  case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
168  case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
169    Expr = MCSymbolRefExpr::Create(Sym, Ctx);
170    // Subtract the pic base.
171    Expr = MCBinaryExpr::CreateSub(Expr,
172                            MCSymbolRefExpr::Create(MF.getPICBaseSymbol(), Ctx),
173                                   Ctx);
174    if (MO.isJTI() && MAI.hasSetDirective()) {
175      // If .set directive is supported, use it to reduce the number of
176      // relocations the assembler will generate for differences between
177      // local labels. This is only safe when the symbols are in the same
178      // section so we are restricting it to jumptable references.
179      MCSymbol *Label = Ctx.CreateTempSymbol();
180      AsmPrinter.OutStreamer.EmitAssignment(Label, Expr);
181      Expr = MCSymbolRefExpr::Create(Label, Ctx);
182    }
183    break;
184  }
185
186  if (Expr == 0)
187    Expr = MCSymbolRefExpr::Create(Sym, RefKind, Ctx);
188
189  if (!MO.isJTI() && MO.getOffset())
190    Expr = MCBinaryExpr::CreateAdd(Expr,
191                                   MCConstantExpr::Create(MO.getOffset(), Ctx),
192                                   Ctx);
193  return MCOperand::CreateExpr(Expr);
194}
195
196
197
198static void lower_subreg32(MCInst *MI, unsigned OpNo) {
199  // Convert registers in the addr mode according to subreg32.
200  unsigned Reg = MI->getOperand(OpNo).getReg();
201  if (Reg != 0)
202    MI->getOperand(OpNo).setReg(getX86SubSuperRegister(Reg, MVT::i32));
203}
204
205static void lower_lea64_32mem(MCInst *MI, unsigned OpNo) {
206  // Convert registers in the addr mode according to subreg64.
207  for (unsigned i = 0; i != 4; ++i) {
208    if (!MI->getOperand(OpNo+i).isReg()) continue;
209
210    unsigned Reg = MI->getOperand(OpNo+i).getReg();
211    if (Reg == 0) continue;
212
213    MI->getOperand(OpNo+i).setReg(getX86SubSuperRegister(Reg, MVT::i64));
214  }
215}
216
217/// LowerSubReg32_Op0 - Things like MOVZX16rr8 -> MOVZX32rr8.
218static void LowerSubReg32_Op0(MCInst &OutMI, unsigned NewOpc) {
219  OutMI.setOpcode(NewOpc);
220  lower_subreg32(&OutMI, 0);
221}
222/// LowerUnaryToTwoAddr - R = setb   -> R = sbb R, R
223static void LowerUnaryToTwoAddr(MCInst &OutMI, unsigned NewOpc) {
224  OutMI.setOpcode(NewOpc);
225  OutMI.addOperand(OutMI.getOperand(0));
226  OutMI.addOperand(OutMI.getOperand(0));
227}
228
229/// \brief Simplify FOO $imm, %{al,ax,eax,rax} to FOO $imm, for instruction with
230/// a short fixed-register form.
231static void SimplifyShortImmForm(MCInst &Inst, unsigned Opcode) {
232  unsigned ImmOp = Inst.getNumOperands() - 1;
233  assert(Inst.getOperand(0).isReg() && Inst.getOperand(ImmOp).isImm() &&
234         ((Inst.getNumOperands() == 3 && Inst.getOperand(1).isReg() &&
235           Inst.getOperand(0).getReg() == Inst.getOperand(1).getReg()) ||
236          Inst.getNumOperands() == 2) && "Unexpected instruction!");
237
238  // Check whether the destination register can be fixed.
239  unsigned Reg = Inst.getOperand(0).getReg();
240  if (Reg != X86::AL && Reg != X86::AX && Reg != X86::EAX && Reg != X86::RAX)
241    return;
242
243  // If so, rewrite the instruction.
244  MCOperand Saved = Inst.getOperand(ImmOp);
245  Inst = MCInst();
246  Inst.setOpcode(Opcode);
247  Inst.addOperand(Saved);
248}
249
250/// \brief Simplify things like MOV32rm to MOV32o32a.
251static void SimplifyShortMoveForm(X86AsmPrinter &Printer, MCInst &Inst,
252                                  unsigned Opcode) {
253  // Don't make these simplifications in 64-bit mode; other assemblers don't
254  // perform them because they make the code larger.
255  if (Printer.getSubtarget().is64Bit())
256    return;
257
258  bool IsStore = Inst.getOperand(0).isReg() && Inst.getOperand(1).isReg();
259  unsigned AddrBase = IsStore;
260  unsigned RegOp = IsStore ? 0 : 5;
261  unsigned AddrOp = AddrBase + 3;
262  assert(Inst.getNumOperands() == 6 && Inst.getOperand(RegOp).isReg() &&
263         Inst.getOperand(AddrBase + 0).isReg() && // base
264         Inst.getOperand(AddrBase + 1).isImm() && // scale
265         Inst.getOperand(AddrBase + 2).isReg() && // index register
266         (Inst.getOperand(AddrOp).isExpr() ||     // address
267          Inst.getOperand(AddrOp).isImm())&&
268         Inst.getOperand(AddrBase + 4).isReg() && // segment
269         "Unexpected instruction!");
270
271  // Check whether the destination register can be fixed.
272  unsigned Reg = Inst.getOperand(RegOp).getReg();
273  if (Reg != X86::AL && Reg != X86::AX && Reg != X86::EAX && Reg != X86::RAX)
274    return;
275
276  // Check whether this is an absolute address.
277  // FIXME: We know TLVP symbol refs aren't, but there should be a better way
278  // to do this here.
279  bool Absolute = true;
280  if (Inst.getOperand(AddrOp).isExpr()) {
281    const MCExpr *MCE = Inst.getOperand(AddrOp).getExpr();
282    if (const MCSymbolRefExpr *SRE = dyn_cast<MCSymbolRefExpr>(MCE))
283      if (SRE->getKind() == MCSymbolRefExpr::VK_TLVP)
284        Absolute = false;
285  }
286
287  if (Absolute &&
288      (Inst.getOperand(AddrBase + 0).getReg() != 0 ||
289       Inst.getOperand(AddrBase + 2).getReg() != 0 ||
290       Inst.getOperand(AddrBase + 4).getReg() != 0 ||
291       Inst.getOperand(AddrBase + 1).getImm() != 1))
292    return;
293
294  // If so, rewrite the instruction.
295  MCOperand Saved = Inst.getOperand(AddrOp);
296  Inst = MCInst();
297  Inst.setOpcode(Opcode);
298  Inst.addOperand(Saved);
299}
300
301void X86MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
302  OutMI.setOpcode(MI->getOpcode());
303
304  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
305    const MachineOperand &MO = MI->getOperand(i);
306
307    MCOperand MCOp;
308    switch (MO.getType()) {
309    default:
310      MI->dump();
311      llvm_unreachable("unknown operand type");
312    case MachineOperand::MO_Register:
313      // Ignore all implicit register operands.
314      if (MO.isImplicit()) continue;
315      MCOp = MCOperand::CreateReg(MO.getReg());
316      break;
317    case MachineOperand::MO_Immediate:
318      MCOp = MCOperand::CreateImm(MO.getImm());
319      break;
320    case MachineOperand::MO_MachineBasicBlock:
321      MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
322                       MO.getMBB()->getSymbol(), Ctx));
323      break;
324    case MachineOperand::MO_GlobalAddress:
325    case MachineOperand::MO_ExternalSymbol:
326      MCOp = LowerSymbolOperand(MO, GetSymbolFromOperand(MO));
327      break;
328    case MachineOperand::MO_JumpTableIndex:
329      MCOp = LowerSymbolOperand(MO, AsmPrinter.GetJTISymbol(MO.getIndex()));
330      break;
331    case MachineOperand::MO_ConstantPoolIndex:
332      MCOp = LowerSymbolOperand(MO, AsmPrinter.GetCPISymbol(MO.getIndex()));
333      break;
334    case MachineOperand::MO_BlockAddress:
335      MCOp = LowerSymbolOperand(MO,
336                     AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress()));
337      break;
338    }
339
340    OutMI.addOperand(MCOp);
341  }
342
343  // Handle a few special cases to eliminate operand modifiers.
344ReSimplify:
345  switch (OutMI.getOpcode()) {
346  case X86::LEA64_32r: // Handle 'subreg rewriting' for the lea64_32mem operand.
347    lower_lea64_32mem(&OutMI, 1);
348    // FALL THROUGH.
349  case X86::LEA64r:
350  case X86::LEA16r:
351  case X86::LEA32r:
352    // LEA should have a segment register, but it must be empty.
353    assert(OutMI.getNumOperands() == 1+X86::AddrNumOperands &&
354           "Unexpected # of LEA operands");
355    assert(OutMI.getOperand(1+X86::AddrSegmentReg).getReg() == 0 &&
356           "LEA has segment specified!");
357    break;
358  case X86::MOVZX16rr8:   LowerSubReg32_Op0(OutMI, X86::MOVZX32rr8); break;
359  case X86::MOVZX16rm8:   LowerSubReg32_Op0(OutMI, X86::MOVZX32rm8); break;
360  case X86::MOVSX16rr8:   LowerSubReg32_Op0(OutMI, X86::MOVSX32rr8); break;
361  case X86::MOVSX16rm8:   LowerSubReg32_Op0(OutMI, X86::MOVSX32rm8); break;
362  case X86::MOVZX64rr32:  LowerSubReg32_Op0(OutMI, X86::MOV32rr); break;
363  case X86::MOVZX64rm32:  LowerSubReg32_Op0(OutMI, X86::MOV32rm); break;
364  case X86::MOV64ri64i32: LowerSubReg32_Op0(OutMI, X86::MOV32ri); break;
365  case X86::MOVZX64rr8:   LowerSubReg32_Op0(OutMI, X86::MOVZX32rr8); break;
366  case X86::MOVZX64rm8:   LowerSubReg32_Op0(OutMI, X86::MOVZX32rm8); break;
367  case X86::MOVZX64rr16:  LowerSubReg32_Op0(OutMI, X86::MOVZX32rr16); break;
368  case X86::MOVZX64rm16:  LowerSubReg32_Op0(OutMI, X86::MOVZX32rm16); break;
369  case X86::SETB_C8r:     LowerUnaryToTwoAddr(OutMI, X86::SBB8rr); break;
370  case X86::SETB_C16r:    LowerUnaryToTwoAddr(OutMI, X86::SBB16rr); break;
371  case X86::SETB_C32r:    LowerUnaryToTwoAddr(OutMI, X86::SBB32rr); break;
372  case X86::SETB_C64r:    LowerUnaryToTwoAddr(OutMI, X86::SBB64rr); break;
373  case X86::MOV8r0:       LowerUnaryToTwoAddr(OutMI, X86::XOR8rr); break;
374  case X86::MOV32r0:      LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); break;
375  case X86::FsFLD0SS:      LowerUnaryToTwoAddr(OutMI, X86::PXORrr); break;
376  case X86::FsFLD0SD:      LowerUnaryToTwoAddr(OutMI, X86::PXORrr); break;
377  case X86::VFsFLD0SS:     LowerUnaryToTwoAddr(OutMI, X86::VPXORrr); break;
378  case X86::VFsFLD0SD:     LowerUnaryToTwoAddr(OutMI, X86::VPXORrr); break;
379  case X86::V_SET0PS:      LowerUnaryToTwoAddr(OutMI, X86::XORPSrr); break;
380  case X86::V_SET0PD:      LowerUnaryToTwoAddr(OutMI, X86::XORPDrr); break;
381  case X86::V_SET0PI:      LowerUnaryToTwoAddr(OutMI, X86::PXORrr); break;
382  case X86::V_SETALLONES:  LowerUnaryToTwoAddr(OutMI, X86::PCMPEQDrr); break;
383  case X86::AVX_SET0PS:    LowerUnaryToTwoAddr(OutMI, X86::VXORPSrr); break;
384  case X86::AVX_SET0PSY:   LowerUnaryToTwoAddr(OutMI, X86::VXORPSYrr); break;
385  case X86::AVX_SET0PD:    LowerUnaryToTwoAddr(OutMI, X86::VXORPDrr); break;
386  case X86::AVX_SET0PDY:   LowerUnaryToTwoAddr(OutMI, X86::VXORPDYrr); break;
387  case X86::AVX_SET0PI:    LowerUnaryToTwoAddr(OutMI, X86::VPXORrr); break;
388
389  case X86::MOV16r0:
390    LowerSubReg32_Op0(OutMI, X86::MOV32r0);   // MOV16r0 -> MOV32r0
391    LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
392    break;
393  case X86::MOV64r0:
394    LowerSubReg32_Op0(OutMI, X86::MOV32r0);   // MOV64r0 -> MOV32r0
395    LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
396    break;
397
398  // TAILJMPr64, [WIN]CALL64r, [WIN]CALL64pcrel32 - These instructions have
399  // register inputs modeled as normal uses instead of implicit uses.  As such,
400  // truncate off all but the first operand (the callee).  FIXME: Change isel.
401  case X86::TAILJMPr64:
402  case X86::CALL64r:
403  case X86::CALL64pcrel32:
404  case X86::WINCALL64r:
405  case X86::WINCALL64pcrel32: {
406    unsigned Opcode = OutMI.getOpcode();
407    MCOperand Saved = OutMI.getOperand(0);
408    OutMI = MCInst();
409    OutMI.setOpcode(Opcode);
410    OutMI.addOperand(Saved);
411    break;
412  }
413
414  case X86::EH_RETURN:
415  case X86::EH_RETURN64: {
416    OutMI = MCInst();
417    OutMI.setOpcode(X86::RET);
418    break;
419  }
420
421  // TAILJMPd, TAILJMPd64 - Lower to the correct jump instructions.
422  case X86::TAILJMPr:
423  case X86::TAILJMPd:
424  case X86::TAILJMPd64: {
425    unsigned Opcode;
426    switch (OutMI.getOpcode()) {
427    default: assert(0 && "Invalid opcode");
428    case X86::TAILJMPr: Opcode = X86::JMP32r; break;
429    case X86::TAILJMPd:
430    case X86::TAILJMPd64: Opcode = X86::JMP_1; break;
431    }
432
433    MCOperand Saved = OutMI.getOperand(0);
434    OutMI = MCInst();
435    OutMI.setOpcode(Opcode);
436    OutMI.addOperand(Saved);
437    break;
438  }
439
440  // These are pseudo-ops for OR to help with the OR->ADD transformation.  We do
441  // this with an ugly goto in case the resultant OR uses EAX and needs the
442  // short form.
443  case X86::ADD16rr_DB:   OutMI.setOpcode(X86::OR16rr); goto ReSimplify;
444  case X86::ADD32rr_DB:   OutMI.setOpcode(X86::OR32rr); goto ReSimplify;
445  case X86::ADD64rr_DB:   OutMI.setOpcode(X86::OR64rr); goto ReSimplify;
446  case X86::ADD16ri_DB:   OutMI.setOpcode(X86::OR16ri); goto ReSimplify;
447  case X86::ADD32ri_DB:   OutMI.setOpcode(X86::OR32ri); goto ReSimplify;
448  case X86::ADD64ri32_DB: OutMI.setOpcode(X86::OR64ri32); goto ReSimplify;
449  case X86::ADD16ri8_DB:  OutMI.setOpcode(X86::OR16ri8); goto ReSimplify;
450  case X86::ADD32ri8_DB:  OutMI.setOpcode(X86::OR32ri8); goto ReSimplify;
451  case X86::ADD64ri8_DB:  OutMI.setOpcode(X86::OR64ri8); goto ReSimplify;
452
453  // The assembler backend wants to see branches in their small form and relax
454  // them to their large form.  The JIT can only handle the large form because
455  // it does not do relaxation.  For now, translate the large form to the
456  // small one here.
457  case X86::JMP_4: OutMI.setOpcode(X86::JMP_1); break;
458  case X86::JO_4:  OutMI.setOpcode(X86::JO_1); break;
459  case X86::JNO_4: OutMI.setOpcode(X86::JNO_1); break;
460  case X86::JB_4:  OutMI.setOpcode(X86::JB_1); break;
461  case X86::JAE_4: OutMI.setOpcode(X86::JAE_1); break;
462  case X86::JE_4:  OutMI.setOpcode(X86::JE_1); break;
463  case X86::JNE_4: OutMI.setOpcode(X86::JNE_1); break;
464  case X86::JBE_4: OutMI.setOpcode(X86::JBE_1); break;
465  case X86::JA_4:  OutMI.setOpcode(X86::JA_1); break;
466  case X86::JS_4:  OutMI.setOpcode(X86::JS_1); break;
467  case X86::JNS_4: OutMI.setOpcode(X86::JNS_1); break;
468  case X86::JP_4:  OutMI.setOpcode(X86::JP_1); break;
469  case X86::JNP_4: OutMI.setOpcode(X86::JNP_1); break;
470  case X86::JL_4:  OutMI.setOpcode(X86::JL_1); break;
471  case X86::JGE_4: OutMI.setOpcode(X86::JGE_1); break;
472  case X86::JLE_4: OutMI.setOpcode(X86::JLE_1); break;
473  case X86::JG_4:  OutMI.setOpcode(X86::JG_1); break;
474
475  // We don't currently select the correct instruction form for instructions
476  // which have a short %eax, etc. form. Handle this by custom lowering, for
477  // now.
478  //
479  // Note, we are currently not handling the following instructions:
480  // MOV64ao8, MOV64o8a
481  // XCHG16ar, XCHG32ar, XCHG64ar
482  case X86::MOV8mr_NOREX:
483  case X86::MOV8mr:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8ao8); break;
484  case X86::MOV8rm_NOREX:
485  case X86::MOV8rm:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8o8a); break;
486  case X86::MOV16mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16ao16); break;
487  case X86::MOV16rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16o16a); break;
488  case X86::MOV32mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32ao32); break;
489  case X86::MOV32rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32o32a); break;
490
491  case X86::ADC8ri:     SimplifyShortImmForm(OutMI, X86::ADC8i8);    break;
492  case X86::ADC16ri:    SimplifyShortImmForm(OutMI, X86::ADC16i16);  break;
493  case X86::ADC32ri:    SimplifyShortImmForm(OutMI, X86::ADC32i32);  break;
494  case X86::ADC64ri32:  SimplifyShortImmForm(OutMI, X86::ADC64i32);  break;
495  case X86::ADD8ri:     SimplifyShortImmForm(OutMI, X86::ADD8i8);    break;
496  case X86::ADD16ri:    SimplifyShortImmForm(OutMI, X86::ADD16i16);  break;
497  case X86::ADD32ri:    SimplifyShortImmForm(OutMI, X86::ADD32i32);  break;
498  case X86::ADD64ri32:  SimplifyShortImmForm(OutMI, X86::ADD64i32);  break;
499  case X86::AND8ri:     SimplifyShortImmForm(OutMI, X86::AND8i8);    break;
500  case X86::AND16ri:    SimplifyShortImmForm(OutMI, X86::AND16i16);  break;
501  case X86::AND32ri:    SimplifyShortImmForm(OutMI, X86::AND32i32);  break;
502  case X86::AND64ri32:  SimplifyShortImmForm(OutMI, X86::AND64i32);  break;
503  case X86::CMP8ri:     SimplifyShortImmForm(OutMI, X86::CMP8i8);    break;
504  case X86::CMP16ri:    SimplifyShortImmForm(OutMI, X86::CMP16i16);  break;
505  case X86::CMP32ri:    SimplifyShortImmForm(OutMI, X86::CMP32i32);  break;
506  case X86::CMP64ri32:  SimplifyShortImmForm(OutMI, X86::CMP64i32);  break;
507  case X86::OR8ri:      SimplifyShortImmForm(OutMI, X86::OR8i8);     break;
508  case X86::OR16ri:     SimplifyShortImmForm(OutMI, X86::OR16i16);   break;
509  case X86::OR32ri:     SimplifyShortImmForm(OutMI, X86::OR32i32);   break;
510  case X86::OR64ri32:   SimplifyShortImmForm(OutMI, X86::OR64i32);   break;
511  case X86::SBB8ri:     SimplifyShortImmForm(OutMI, X86::SBB8i8);    break;
512  case X86::SBB16ri:    SimplifyShortImmForm(OutMI, X86::SBB16i16);  break;
513  case X86::SBB32ri:    SimplifyShortImmForm(OutMI, X86::SBB32i32);  break;
514  case X86::SBB64ri32:  SimplifyShortImmForm(OutMI, X86::SBB64i32);  break;
515  case X86::SUB8ri:     SimplifyShortImmForm(OutMI, X86::SUB8i8);    break;
516  case X86::SUB16ri:    SimplifyShortImmForm(OutMI, X86::SUB16i16);  break;
517  case X86::SUB32ri:    SimplifyShortImmForm(OutMI, X86::SUB32i32);  break;
518  case X86::SUB64ri32:  SimplifyShortImmForm(OutMI, X86::SUB64i32);  break;
519  case X86::TEST8ri:    SimplifyShortImmForm(OutMI, X86::TEST8i8);   break;
520  case X86::TEST16ri:   SimplifyShortImmForm(OutMI, X86::TEST16i16); break;
521  case X86::TEST32ri:   SimplifyShortImmForm(OutMI, X86::TEST32i32); break;
522  case X86::TEST64ri32: SimplifyShortImmForm(OutMI, X86::TEST64i32); break;
523  case X86::XOR8ri:     SimplifyShortImmForm(OutMI, X86::XOR8i8);    break;
524  case X86::XOR16ri:    SimplifyShortImmForm(OutMI, X86::XOR16i16);  break;
525  case X86::XOR32ri:    SimplifyShortImmForm(OutMI, X86::XOR32i32);  break;
526  case X86::XOR64ri32:  SimplifyShortImmForm(OutMI, X86::XOR64i32);  break;
527  }
528}
529
530static void LowerTlsAddr(MCStreamer &OutStreamer,
531                         X86MCInstLower &MCInstLowering,
532                         const MachineInstr &MI) {
533  bool is64Bits = MI.getOpcode() == X86::TLS_addr64;
534  MCContext &context = OutStreamer.getContext();
535
536  if (is64Bits) {
537    MCInst prefix;
538    prefix.setOpcode(X86::DATA16_PREFIX);
539    OutStreamer.EmitInstruction(prefix);
540  }
541  MCSymbol *sym = MCInstLowering.GetSymbolFromOperand(MI.getOperand(3));
542  const MCSymbolRefExpr *symRef =
543    MCSymbolRefExpr::Create(sym, MCSymbolRefExpr::VK_TLSGD, context);
544
545  MCInst LEA;
546  if (is64Bits) {
547    LEA.setOpcode(X86::LEA64r);
548    LEA.addOperand(MCOperand::CreateReg(X86::RDI)); // dest
549    LEA.addOperand(MCOperand::CreateReg(X86::RIP)); // base
550    LEA.addOperand(MCOperand::CreateImm(1));        // scale
551    LEA.addOperand(MCOperand::CreateReg(0));        // index
552    LEA.addOperand(MCOperand::CreateExpr(symRef));  // disp
553    LEA.addOperand(MCOperand::CreateReg(0));        // seg
554  } else {
555    LEA.setOpcode(X86::LEA32r);
556    LEA.addOperand(MCOperand::CreateReg(X86::EAX)); // dest
557    LEA.addOperand(MCOperand::CreateReg(0));        // base
558    LEA.addOperand(MCOperand::CreateImm(1));        // scale
559    LEA.addOperand(MCOperand::CreateReg(X86::EBX)); // index
560    LEA.addOperand(MCOperand::CreateExpr(symRef));  // disp
561    LEA.addOperand(MCOperand::CreateReg(0));        // seg
562  }
563  OutStreamer.EmitInstruction(LEA);
564
565  if (is64Bits) {
566    MCInst prefix;
567    prefix.setOpcode(X86::DATA16_PREFIX);
568    OutStreamer.EmitInstruction(prefix);
569    prefix.setOpcode(X86::DATA16_PREFIX);
570    OutStreamer.EmitInstruction(prefix);
571    prefix.setOpcode(X86::REX64_PREFIX);
572    OutStreamer.EmitInstruction(prefix);
573  }
574
575  MCInst call;
576  if (is64Bits)
577    call.setOpcode(X86::CALL64pcrel32);
578  else
579    call.setOpcode(X86::CALLpcrel32);
580  StringRef name = is64Bits ? "__tls_get_addr" : "___tls_get_addr";
581  MCSymbol *tlsGetAddr = context.GetOrCreateSymbol(name);
582  const MCSymbolRefExpr *tlsRef =
583    MCSymbolRefExpr::Create(tlsGetAddr,
584                            MCSymbolRefExpr::VK_PLT,
585                            context);
586
587  call.addOperand(MCOperand::CreateExpr(tlsRef));
588  OutStreamer.EmitInstruction(call);
589}
590
591void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
592  X86MCInstLower MCInstLowering(Mang, *MF, *this);
593  switch (MI->getOpcode()) {
594  case TargetOpcode::DBG_VALUE:
595    if (isVerbose() && OutStreamer.hasRawTextSupport()) {
596      std::string TmpStr;
597      raw_string_ostream OS(TmpStr);
598      PrintDebugValueComment(MI, OS);
599      OutStreamer.EmitRawText(StringRef(OS.str()));
600    }
601    return;
602
603  // Emit nothing here but a comment if we can.
604  case X86::Int_MemBarrier:
605    if (OutStreamer.hasRawTextSupport())
606      OutStreamer.EmitRawText(StringRef("\t#MEMBARRIER"));
607    return;
608
609
610  case X86::EH_RETURN:
611  case X86::EH_RETURN64: {
612    // Lower these as normal, but add some comments.
613    unsigned Reg = MI->getOperand(0).getReg();
614    OutStreamer.AddComment(StringRef("eh_return, addr: %") +
615                           X86ATTInstPrinter::getRegisterName(Reg));
616    break;
617  }
618  case X86::TAILJMPr:
619  case X86::TAILJMPd:
620  case X86::TAILJMPd64:
621    // Lower these as normal, but add some comments.
622    OutStreamer.AddComment("TAILCALL");
623    break;
624
625  case X86::TLS_addr32:
626  case X86::TLS_addr64:
627    return LowerTlsAddr(OutStreamer, MCInstLowering, *MI);
628
629  case X86::MOVPC32r: {
630    MCInst TmpInst;
631    // This is a pseudo op for a two instruction sequence with a label, which
632    // looks like:
633    //     call "L1$pb"
634    // "L1$pb":
635    //     popl %esi
636
637    // Emit the call.
638    MCSymbol *PICBase = MF->getPICBaseSymbol();
639    TmpInst.setOpcode(X86::CALLpcrel32);
640    // FIXME: We would like an efficient form for this, so we don't have to do a
641    // lot of extra uniquing.
642    TmpInst.addOperand(MCOperand::CreateExpr(MCSymbolRefExpr::Create(PICBase,
643                                                                 OutContext)));
644    OutStreamer.EmitInstruction(TmpInst);
645
646    // Emit the label.
647    OutStreamer.EmitLabel(PICBase);
648
649    // popl $reg
650    TmpInst.setOpcode(X86::POP32r);
651    TmpInst.getOperand(0) = MCOperand::CreateReg(MI->getOperand(0).getReg());
652    OutStreamer.EmitInstruction(TmpInst);
653    return;
654  }
655
656  case X86::ADD32ri: {
657    // Lower the MO_GOT_ABSOLUTE_ADDRESS form of ADD32ri.
658    if (MI->getOperand(2).getTargetFlags() != X86II::MO_GOT_ABSOLUTE_ADDRESS)
659      break;
660
661    // Okay, we have something like:
662    //  EAX = ADD32ri EAX, MO_GOT_ABSOLUTE_ADDRESS(@MYGLOBAL)
663
664    // For this, we want to print something like:
665    //   MYGLOBAL + (. - PICBASE)
666    // However, we can't generate a ".", so just emit a new label here and refer
667    // to it.
668    MCSymbol *DotSym = OutContext.CreateTempSymbol();
669    OutStreamer.EmitLabel(DotSym);
670
671    // Now that we have emitted the label, lower the complex operand expression.
672    MCSymbol *OpSym = MCInstLowering.GetSymbolFromOperand(MI->getOperand(2));
673
674    const MCExpr *DotExpr = MCSymbolRefExpr::Create(DotSym, OutContext);
675    const MCExpr *PICBase =
676      MCSymbolRefExpr::Create(MF->getPICBaseSymbol(), OutContext);
677    DotExpr = MCBinaryExpr::CreateSub(DotExpr, PICBase, OutContext);
678
679    DotExpr = MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(OpSym,OutContext),
680                                      DotExpr, OutContext);
681
682    MCInst TmpInst;
683    TmpInst.setOpcode(X86::ADD32ri);
684    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
685    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
686    TmpInst.addOperand(MCOperand::CreateExpr(DotExpr));
687    OutStreamer.EmitInstruction(TmpInst);
688    return;
689  }
690  }
691
692  MCInst TmpInst;
693  MCInstLowering.Lower(MI, TmpInst);
694  OutStreamer.EmitInstruction(TmpInst);
695}
696
697