1//===-- X86AsmPrinter.cpp - Convert X86 LLVM code to AT&T assembly --------===//
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 a printer that converts from our internal representation
11// of machine-dependent LLVM code to X86 machine code.
12//
13//===----------------------------------------------------------------------===//
14
15#include "X86AsmPrinter.h"
16#include "X86MCInstLower.h"
17#include "X86.h"
18#include "X86COFFMachineModuleInfo.h"
19#include "X86MachineFunctionInfo.h"
20#include "X86TargetMachine.h"
21#include "InstPrinter/X86ATTInstPrinter.h"
22#include "llvm/CallingConv.h"
23#include "llvm/DebugInfo.h"
24#include "llvm/DerivedTypes.h"
25#include "llvm/Module.h"
26#include "llvm/Type.h"
27#include "llvm/Assembly/Writer.h"
28#include "llvm/MC/MCAsmInfo.h"
29#include "llvm/MC/MCContext.h"
30#include "llvm/MC/MCExpr.h"
31#include "llvm/MC/MCSectionMachO.h"
32#include "llvm/MC/MCStreamer.h"
33#include "llvm/MC/MCSymbol.h"
34#include "llvm/CodeGen/MachineJumpTableInfo.h"
35#include "llvm/CodeGen/MachineModuleInfoImpls.h"
36#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
37#include "llvm/Target/Mangler.h"
38#include "llvm/Target/TargetOptions.h"
39#include "llvm/Support/COFF.h"
40#include "llvm/Support/Debug.h"
41#include "llvm/Support/ErrorHandling.h"
42#include "llvm/Support/TargetRegistry.h"
43#include "llvm/ADT/SmallString.h"
44using namespace llvm;
45
46//===----------------------------------------------------------------------===//
47// Primitive Helper Functions.
48//===----------------------------------------------------------------------===//
49
50/// runOnMachineFunction - Emit the function body.
51///
52bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
53  SetupMachineFunction(MF);
54
55  if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
56    bool Intrn = MF.getFunction()->hasInternalLinkage();
57    OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
58    OutStreamer.EmitCOFFSymbolStorageClass(Intrn ? COFF::IMAGE_SYM_CLASS_STATIC
59                                              : COFF::IMAGE_SYM_CLASS_EXTERNAL);
60    OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
61                                               << COFF::SCT_COMPLEX_TYPE_SHIFT);
62    OutStreamer.EndCOFFSymbolDef();
63  }
64
65  // Have common code print out the function header with linkage info etc.
66  EmitFunctionHeader();
67
68  // Emit the rest of the function body.
69  EmitFunctionBody();
70
71  // We didn't modify anything.
72  return false;
73}
74
75/// printSymbolOperand - Print a raw symbol reference operand.  This handles
76/// jump tables, constant pools, global address and external symbols, all of
77/// which print to a label with various suffixes for relocation types etc.
78void X86AsmPrinter::printSymbolOperand(const MachineOperand &MO,
79                                       raw_ostream &O) {
80  switch (MO.getType()) {
81  default: llvm_unreachable("unknown symbol type!");
82  case MachineOperand::MO_JumpTableIndex:
83    O << *GetJTISymbol(MO.getIndex());
84    break;
85  case MachineOperand::MO_ConstantPoolIndex:
86    O << *GetCPISymbol(MO.getIndex());
87    printOffset(MO.getOffset(), O);
88    break;
89  case MachineOperand::MO_GlobalAddress: {
90    const GlobalValue *GV = MO.getGlobal();
91
92    MCSymbol *GVSym;
93    if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
94      GVSym = GetSymbolWithGlobalValueBase(GV, "$stub");
95    else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
96             MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
97             MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
98      GVSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
99    else
100      GVSym = Mang->getSymbol(GV);
101
102    // Handle dllimport linkage.
103    if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
104      GVSym = OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName());
105
106    if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
107        MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) {
108      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
109      MachineModuleInfoImpl::StubValueTy &StubSym =
110        MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym);
111      if (StubSym.getPointer() == 0)
112        StubSym = MachineModuleInfoImpl::
113          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
114    } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){
115      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
116      MachineModuleInfoImpl::StubValueTy &StubSym =
117        MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry(Sym);
118      if (StubSym.getPointer() == 0)
119        StubSym = MachineModuleInfoImpl::
120          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
121    } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
122      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
123      MachineModuleInfoImpl::StubValueTy &StubSym =
124        MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
125      if (StubSym.getPointer() == 0)
126        StubSym = MachineModuleInfoImpl::
127          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
128    }
129
130    // If the name begins with a dollar-sign, enclose it in parens.  We do this
131    // to avoid having it look like an integer immediate to the assembler.
132    if (GVSym->getName()[0] != '$')
133      O << *GVSym;
134    else
135      O << '(' << *GVSym << ')';
136    printOffset(MO.getOffset(), O);
137    break;
138  }
139  case MachineOperand::MO_ExternalSymbol: {
140    const MCSymbol *SymToPrint;
141    if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
142      SmallString<128> TempNameStr;
143      TempNameStr += StringRef(MO.getSymbolName());
144      TempNameStr += StringRef("$stub");
145
146      MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
147      MachineModuleInfoImpl::StubValueTy &StubSym =
148        MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
149      if (StubSym.getPointer() == 0) {
150        TempNameStr.erase(TempNameStr.end()-5, TempNameStr.end());
151        StubSym = MachineModuleInfoImpl::
152          StubValueTy(OutContext.GetOrCreateSymbol(TempNameStr.str()),
153                      true);
154      }
155      SymToPrint = StubSym.getPointer();
156    } else {
157      SymToPrint = GetExternalSymbolSymbol(MO.getSymbolName());
158    }
159
160    // If the name begins with a dollar-sign, enclose it in parens.  We do this
161    // to avoid having it look like an integer immediate to the assembler.
162    if (SymToPrint->getName()[0] != '$')
163      O << *SymToPrint;
164    else
165      O << '(' << *SymToPrint << '(';
166    break;
167  }
168  }
169
170  switch (MO.getTargetFlags()) {
171  default:
172    llvm_unreachable("Unknown target flag on GV operand");
173  case X86II::MO_NO_FLAG:    // No flag.
174    break;
175  case X86II::MO_DARWIN_NONLAZY:
176  case X86II::MO_DLLIMPORT:
177  case X86II::MO_DARWIN_STUB:
178    // These affect the name of the symbol, not any suffix.
179    break;
180  case X86II::MO_GOT_ABSOLUTE_ADDRESS:
181    O << " + [.-" << *MF->getPICBaseSymbol() << ']';
182    break;
183  case X86II::MO_PIC_BASE_OFFSET:
184  case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
185  case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
186    O << '-' << *MF->getPICBaseSymbol();
187    break;
188  case X86II::MO_TLSGD:     O << "@TLSGD";     break;
189  case X86II::MO_TLSLD:     O << "@TLSLD";     break;
190  case X86II::MO_TLSLDM:    O << "@TLSLDM";    break;
191  case X86II::MO_GOTTPOFF:  O << "@GOTTPOFF";  break;
192  case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
193  case X86II::MO_TPOFF:     O << "@TPOFF";     break;
194  case X86II::MO_DTPOFF:    O << "@DTPOFF";    break;
195  case X86II::MO_NTPOFF:    O << "@NTPOFF";    break;
196  case X86II::MO_GOTNTPOFF: O << "@GOTNTPOFF"; break;
197  case X86II::MO_GOTPCREL:  O << "@GOTPCREL";  break;
198  case X86II::MO_GOT:       O << "@GOT";       break;
199  case X86II::MO_GOTOFF:    O << "@GOTOFF";    break;
200  case X86II::MO_PLT:       O << "@PLT";       break;
201  case X86II::MO_TLVP:      O << "@TLVP";      break;
202  case X86II::MO_TLVP_PIC_BASE:
203    O << "@TLVP" << '-' << *MF->getPICBaseSymbol();
204    break;
205  case X86II::MO_SECREL:      O << "@SECREL";      break;
206  }
207}
208
209/// printPCRelImm - This is used to print an immediate value that ends up
210/// being encoded as a pc-relative value.  These print slightly differently, for
211/// example, a $ is not emitted.
212void X86AsmPrinter::printPCRelImm(const MachineInstr *MI, unsigned OpNo,
213                                    raw_ostream &O) {
214  const MachineOperand &MO = MI->getOperand(OpNo);
215  switch (MO.getType()) {
216  default: llvm_unreachable("Unknown pcrel immediate operand");
217  case MachineOperand::MO_Register:
218    // pc-relativeness was handled when computing the value in the reg.
219    printOperand(MI, OpNo, O);
220    return;
221  case MachineOperand::MO_Immediate:
222    O << MO.getImm();
223    return;
224  case MachineOperand::MO_MachineBasicBlock:
225    O << *MO.getMBB()->getSymbol();
226    return;
227  case MachineOperand::MO_GlobalAddress:
228  case MachineOperand::MO_ExternalSymbol:
229    printSymbolOperand(MO, O);
230    return;
231  }
232}
233
234
235void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
236                                 raw_ostream &O, const char *Modifier,
237                                 unsigned AsmVariant) {
238  const MachineOperand &MO = MI->getOperand(OpNo);
239  switch (MO.getType()) {
240  default: llvm_unreachable("unknown operand type!");
241  case MachineOperand::MO_Register: {
242    // FIXME: Enumerating AsmVariant, so we can remove magic number.
243    if (AsmVariant == 0) O << '%';
244    unsigned Reg = MO.getReg();
245    if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
246      MVT::SimpleValueType VT = (strcmp(Modifier+6,"64") == 0) ?
247        MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
248                    ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
249      Reg = getX86SubSuperRegister(Reg, VT);
250    }
251    O << X86ATTInstPrinter::getRegisterName(Reg);
252    return;
253  }
254
255  case MachineOperand::MO_Immediate:
256    O << '$' << MO.getImm();
257    return;
258
259  case MachineOperand::MO_JumpTableIndex:
260  case MachineOperand::MO_ConstantPoolIndex:
261  case MachineOperand::MO_GlobalAddress:
262  case MachineOperand::MO_ExternalSymbol: {
263    O << '$';
264    printSymbolOperand(MO, O);
265    break;
266  }
267  }
268}
269
270void X86AsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op,
271                               raw_ostream &O) {
272  unsigned char value = MI->getOperand(Op).getImm();
273  switch (value) {
274  default: llvm_unreachable("Invalid ssecc argument!");
275  case    0: O << "eq"; break;
276  case    1: O << "lt"; break;
277  case    2: O << "le"; break;
278  case    3: O << "unord"; break;
279  case    4: O << "neq"; break;
280  case    5: O << "nlt"; break;
281  case    6: O << "nle"; break;
282  case    7: O << "ord"; break;
283  case    8: O << "eq_uq"; break;
284  case    9: O << "nge"; break;
285  case  0xa: O << "ngt"; break;
286  case  0xb: O << "false"; break;
287  case  0xc: O << "neq_oq"; break;
288  case  0xd: O << "ge"; break;
289  case  0xe: O << "gt"; break;
290  case  0xf: O << "true"; break;
291  case 0x10: O << "eq_os"; break;
292  case 0x11: O << "lt_oq"; break;
293  case 0x12: O << "le_oq"; break;
294  case 0x13: O << "unord_s"; break;
295  case 0x14: O << "neq_us"; break;
296  case 0x15: O << "nlt_uq"; break;
297  case 0x16: O << "nle_uq"; break;
298  case 0x17: O << "ord_s"; break;
299  case 0x18: O << "eq_us"; break;
300  case 0x19: O << "nge_uq"; break;
301  case 0x1a: O << "ngt_uq"; break;
302  case 0x1b: O << "false_os"; break;
303  case 0x1c: O << "neq_os"; break;
304  case 0x1d: O << "ge_oq"; break;
305  case 0x1e: O << "gt_oq"; break;
306  case 0x1f: O << "true_us"; break;
307  }
308}
309
310void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
311                                         raw_ostream &O, const char *Modifier) {
312  const MachineOperand &BaseReg  = MI->getOperand(Op);
313  const MachineOperand &IndexReg = MI->getOperand(Op+2);
314  const MachineOperand &DispSpec = MI->getOperand(Op+3);
315
316  // If we really don't want to print out (rip), don't.
317  bool HasBaseReg = BaseReg.getReg() != 0;
318  if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
319      BaseReg.getReg() == X86::RIP)
320    HasBaseReg = false;
321
322  // HasParenPart - True if we will print out the () part of the mem ref.
323  bool HasParenPart = IndexReg.getReg() || HasBaseReg;
324
325  if (DispSpec.isImm()) {
326    int DispVal = DispSpec.getImm();
327    if (DispVal || !HasParenPart)
328      O << DispVal;
329  } else {
330    assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
331           DispSpec.isJTI() || DispSpec.isSymbol());
332    printSymbolOperand(MI->getOperand(Op+3), O);
333  }
334
335  if (Modifier && strcmp(Modifier, "H") == 0)
336    O << "+8";
337
338  if (HasParenPart) {
339    assert(IndexReg.getReg() != X86::ESP &&
340           "X86 doesn't allow scaling by ESP");
341
342    O << '(';
343    if (HasBaseReg)
344      printOperand(MI, Op, O, Modifier);
345
346    if (IndexReg.getReg()) {
347      O << ',';
348      printOperand(MI, Op+2, O, Modifier);
349      unsigned ScaleVal = MI->getOperand(Op+1).getImm();
350      if (ScaleVal != 1)
351        O << ',' << ScaleVal;
352    }
353    O << ')';
354  }
355}
356
357void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
358                                      raw_ostream &O, const char *Modifier) {
359  assert(isMem(MI, Op) && "Invalid memory reference!");
360  const MachineOperand &Segment = MI->getOperand(Op+4);
361  if (Segment.getReg()) {
362    printOperand(MI, Op+4, O, Modifier);
363    O << ':';
364  }
365  printLeaMemReference(MI, Op, O, Modifier);
366}
367
368void X86AsmPrinter::printIntelMemReference(const MachineInstr *MI, unsigned Op,
369                                           raw_ostream &O, const char *Modifier,
370                                           unsigned AsmVariant){
371  const MachineOperand &BaseReg  = MI->getOperand(Op);
372  unsigned ScaleVal = MI->getOperand(Op+1).getImm();
373  const MachineOperand &IndexReg = MI->getOperand(Op+2);
374  const MachineOperand &DispSpec = MI->getOperand(Op+3);
375  const MachineOperand &SegReg   = MI->getOperand(Op+4);
376
377  // If this has a segment register, print it.
378  if (SegReg.getReg()) {
379    printOperand(MI, Op+4, O, Modifier, AsmVariant);
380    O << ':';
381  }
382
383  O << '[';
384
385  bool NeedPlus = false;
386  if (BaseReg.getReg()) {
387    printOperand(MI, Op, O, Modifier, AsmVariant);
388    NeedPlus = true;
389  }
390
391  if (IndexReg.getReg()) {
392    if (NeedPlus) O << " + ";
393    if (ScaleVal != 1)
394      O << ScaleVal << '*';
395    printOperand(MI, Op+2, O, Modifier, AsmVariant);
396    NeedPlus = true;
397  }
398
399  assert (DispSpec.isImm() && "Displacement is not an immediate!");
400  int64_t DispVal = DispSpec.getImm();
401  if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg())) {
402    if (NeedPlus) {
403      if (DispVal > 0)
404        O << " + ";
405      else {
406        O << " - ";
407        DispVal = -DispVal;
408      }
409    }
410    O << DispVal;
411  }
412  O << ']';
413}
414
415void X86AsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op,
416                                  raw_ostream &O) {
417  O << *MF->getPICBaseSymbol() << '\n';
418  O << *MF->getPICBaseSymbol() << ':';
419}
420
421bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
422                                      raw_ostream &O) {
423  unsigned Reg = MO.getReg();
424  switch (Mode) {
425  default: return true;  // Unknown mode.
426  case 'b': // Print QImode register
427    Reg = getX86SubSuperRegister(Reg, MVT::i8);
428    break;
429  case 'h': // Print QImode high register
430    Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
431    break;
432  case 'w': // Print HImode register
433    Reg = getX86SubSuperRegister(Reg, MVT::i16);
434    break;
435  case 'k': // Print SImode register
436    Reg = getX86SubSuperRegister(Reg, MVT::i32);
437    break;
438  case 'q': // Print DImode register
439    Reg = getX86SubSuperRegister(Reg, MVT::i64);
440    break;
441  }
442
443  O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
444  return false;
445}
446
447/// PrintAsmOperand - Print out an operand for an inline asm expression.
448///
449bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
450                                    unsigned AsmVariant,
451                                    const char *ExtraCode, raw_ostream &O) {
452  // Does this asm operand have a single letter operand modifier?
453  if (ExtraCode && ExtraCode[0]) {
454    if (ExtraCode[1] != 0) return true; // Unknown modifier.
455
456    const MachineOperand &MO = MI->getOperand(OpNo);
457
458    switch (ExtraCode[0]) {
459    default:
460      // See if this is a generic print operand
461      return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
462    case 'a': // This is an address.  Currently only 'i' and 'r' are expected.
463      if (MO.isImm()) {
464        O << MO.getImm();
465        return false;
466      }
467      if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
468        printSymbolOperand(MO, O);
469        if (Subtarget->isPICStyleRIPRel())
470          O << "(%rip)";
471        return false;
472      }
473      if (MO.isReg()) {
474        O << '(';
475        printOperand(MI, OpNo, O);
476        O << ')';
477        return false;
478      }
479      return true;
480
481    case 'c': // Don't print "$" before a global var name or constant.
482      if (MO.isImm())
483        O << MO.getImm();
484      else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
485        printSymbolOperand(MO, O);
486      else
487        printOperand(MI, OpNo, O);
488      return false;
489
490    case 'A': // Print '*' before a register (it must be a register)
491      if (MO.isReg()) {
492        O << '*';
493        printOperand(MI, OpNo, O);
494        return false;
495      }
496      return true;
497
498    case 'b': // Print QImode register
499    case 'h': // Print QImode high register
500    case 'w': // Print HImode register
501    case 'k': // Print SImode register
502    case 'q': // Print DImode register
503      if (MO.isReg())
504        return printAsmMRegister(MO, ExtraCode[0], O);
505      printOperand(MI, OpNo, O);
506      return false;
507
508    case 'P': // This is the operand of a call, treat specially.
509      printPCRelImm(MI, OpNo, O);
510      return false;
511
512    case 'n':  // Negate the immediate or print a '-' before the operand.
513      // Note: this is a temporary solution. It should be handled target
514      // independently as part of the 'MC' work.
515      if (MO.isImm()) {
516        O << -MO.getImm();
517        return false;
518      }
519      O << '-';
520    }
521  }
522
523  printOperand(MI, OpNo, O, /*Modifier*/ 0, AsmVariant);
524  return false;
525}
526
527bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
528                                          unsigned OpNo, unsigned AsmVariant,
529                                          const char *ExtraCode,
530                                          raw_ostream &O) {
531  if (AsmVariant) {
532    printIntelMemReference(MI, OpNo, O);
533    return false;
534  }
535
536  if (ExtraCode && ExtraCode[0]) {
537    if (ExtraCode[1] != 0) return true; // Unknown modifier.
538
539    switch (ExtraCode[0]) {
540    default: return true;  // Unknown modifier.
541    case 'b': // Print QImode register
542    case 'h': // Print QImode high register
543    case 'w': // Print HImode register
544    case 'k': // Print SImode register
545    case 'q': // Print SImode register
546      // These only apply to registers, ignore on mem.
547      break;
548    case 'H':
549      printMemReference(MI, OpNo, O, "H");
550      return false;
551    case 'P': // Don't print @PLT, but do print as memory.
552      printMemReference(MI, OpNo, O, "no-rip");
553      return false;
554    }
555  }
556  printMemReference(MI, OpNo, O);
557  return false;
558}
559
560void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
561  if (Subtarget->isTargetEnvMacho())
562    OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
563}
564
565
566void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
567  if (Subtarget->isTargetEnvMacho()) {
568    // All darwin targets use mach-o.
569    MachineModuleInfoMachO &MMIMacho =
570      MMI->getObjFileInfo<MachineModuleInfoMachO>();
571
572    // Output stubs for dynamically-linked functions.
573    MachineModuleInfoMachO::SymbolListTy Stubs;
574
575    Stubs = MMIMacho.GetFnStubList();
576    if (!Stubs.empty()) {
577      const MCSection *TheSection =
578        OutContext.getMachOSection("__IMPORT", "__jump_table",
579                                   MCSectionMachO::S_SYMBOL_STUBS |
580                                   MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
581                                   MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
582                                   5, SectionKind::getMetadata());
583      OutStreamer.SwitchSection(TheSection);
584
585      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
586        // L_foo$stub:
587        OutStreamer.EmitLabel(Stubs[i].first);
588        //   .indirect_symbol _foo
589        OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
590                                        MCSA_IndirectSymbol);
591        // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
592        const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
593        OutStreamer.EmitBytes(StringRef(HltInsts, 5), 0/*addrspace*/);
594      }
595
596      Stubs.clear();
597      OutStreamer.AddBlankLine();
598    }
599
600    // Output stubs for external and common global variables.
601    Stubs = MMIMacho.GetGVStubList();
602    if (!Stubs.empty()) {
603      const MCSection *TheSection =
604        OutContext.getMachOSection("__IMPORT", "__pointers",
605                                   MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
606                                   SectionKind::getMetadata());
607      OutStreamer.SwitchSection(TheSection);
608
609      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
610        // L_foo$non_lazy_ptr:
611        OutStreamer.EmitLabel(Stubs[i].first);
612        // .indirect_symbol _foo
613        MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
614        OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
615                                        MCSA_IndirectSymbol);
616        // .long 0
617        if (MCSym.getInt())
618          // External to current translation unit.
619          OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
620        else
621          // Internal to current translation unit.
622          //
623          // When we place the LSDA into the TEXT section, the type info
624          // pointers need to be indirect and pc-rel. We accomplish this by
625          // using NLPs.  However, sometimes the types are local to the file. So
626          // we need to fill in the value for the NLP in those cases.
627          OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
628                                                        OutContext),
629                                4/*size*/, 0/*addrspace*/);
630      }
631      Stubs.clear();
632      OutStreamer.AddBlankLine();
633    }
634
635    Stubs = MMIMacho.GetHiddenGVStubList();
636    if (!Stubs.empty()) {
637      OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
638      EmitAlignment(2);
639
640      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
641        // L_foo$non_lazy_ptr:
642        OutStreamer.EmitLabel(Stubs[i].first);
643        // .long _foo
644        OutStreamer.EmitValue(MCSymbolRefExpr::
645                              Create(Stubs[i].second.getPointer(),
646                                     OutContext),
647                              4/*size*/, 0/*addrspace*/);
648      }
649      Stubs.clear();
650      OutStreamer.AddBlankLine();
651    }
652
653    // Funny Darwin hack: This flag tells the linker that no global symbols
654    // contain code that falls through to other global symbols (e.g. the obvious
655    // implementation of multiple entry points).  If this doesn't occur, the
656    // linker can safely perform dead code stripping.  Since LLVM never
657    // generates code that does this, it is always safe to set.
658    OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
659  }
660
661  if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
662      MMI->usesVAFloatArgument()) {
663    StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
664    MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
665    OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
666  }
667
668  if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
669    X86COFFMachineModuleInfo &COFFMMI =
670      MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
671
672    // Emit type information for external functions
673    typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
674    for (externals_iterator I = COFFMMI.externals_begin(),
675                            E = COFFMMI.externals_end();
676                            I != E; ++I) {
677      OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
678      OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
679      OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
680                                               << COFF::SCT_COMPLEX_TYPE_SHIFT);
681      OutStreamer.EndCOFFSymbolDef();
682    }
683
684    // Necessary for dllexport support
685    std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
686
687    const TargetLoweringObjectFileCOFF &TLOFCOFF =
688      static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());
689
690    for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
691      if (I->hasDLLExportLinkage())
692        DLLExportedFns.push_back(Mang->getSymbol(I));
693
694    for (Module::const_global_iterator I = M.global_begin(),
695           E = M.global_end(); I != E; ++I)
696      if (I->hasDLLExportLinkage())
697        DLLExportedGlobals.push_back(Mang->getSymbol(I));
698
699    // Output linker support code for dllexported globals on windows.
700    if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
701      OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
702      SmallString<128> name;
703      for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
704        if (Subtarget->isTargetWindows())
705          name = " /EXPORT:";
706        else
707          name = " -export:";
708        name += DLLExportedGlobals[i]->getName();
709        if (Subtarget->isTargetWindows())
710          name += ",DATA";
711        else
712        name += ",data";
713        OutStreamer.EmitBytes(name, 0);
714      }
715
716      for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
717        if (Subtarget->isTargetWindows())
718          name = " /EXPORT:";
719        else
720          name = " -export:";
721        name += DLLExportedFns[i]->getName();
722        OutStreamer.EmitBytes(name, 0);
723      }
724    }
725  }
726
727  if (Subtarget->isTargetELF()) {
728    const TargetLoweringObjectFileELF &TLOFELF =
729      static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());
730
731    MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
732
733    // Output stubs for external and common global variables.
734    MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
735    if (!Stubs.empty()) {
736      OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
737      const TargetData *TD = TM.getTargetData();
738
739      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
740        OutStreamer.EmitLabel(Stubs[i].first);
741        OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
742                                    TD->getPointerSize(), 0);
743      }
744      Stubs.clear();
745    }
746  }
747}
748
749MachineLocation
750X86AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
751  MachineLocation Location;
752  assert (MI->getNumOperands() == 7 && "Invalid no. of machine operands!");
753  // Frame address.  Currently handles register +- offset only.
754
755  if (MI->getOperand(0).isReg() && MI->getOperand(3).isImm())
756    Location.set(MI->getOperand(0).getReg(), MI->getOperand(3).getImm());
757  else {
758    DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
759  }
760  return Location;
761}
762
763void X86AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
764                                           raw_ostream &O) {
765  // Only the target-dependent form of DBG_VALUE should get here.
766  // Referencing the offset and metadata as NOps-2 and NOps-1 is
767  // probably portable to other targets; frame pointer location is not.
768  unsigned NOps = MI->getNumOperands();
769  assert(NOps==7);
770  O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
771  // cast away const; DIetc do not take const operands for some reason.
772  DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
773  if (V.getContext().isSubprogram())
774    O << DISubprogram(V.getContext()).getDisplayName() << ":";
775  O << V.getName();
776  O << " <- ";
777  // Frame address.  Currently handles register +- offset only.
778  O << '[';
779  if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg())
780    printOperand(MI, 0, O);
781  else
782    O << "undef";
783  O << '+'; printOperand(MI, 3, O);
784  O << ']';
785  O << "+";
786  printOperand(MI, NOps-2, O);
787}
788
789
790
791//===----------------------------------------------------------------------===//
792// Target Registry Stuff
793//===----------------------------------------------------------------------===//
794
795// Force static initialization.
796extern "C" void LLVMInitializeX86AsmPrinter() {
797  RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
798  RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
799}
800