X86AsmPrinter.cpp revision d4a19b6a72d19a6f90b676aac37118664b7b7a84 
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 "InstPrinter/X86ATTInstPrinter.h"
17#include "InstPrinter/X86IntelInstPrinter.h"
18#include "X86MCInstLower.h"
19#include "X86.h"
20#include "X86COFFMachineModuleInfo.h"
21#include "X86MachineFunctionInfo.h"
22#include "X86TargetMachine.h"
23#include "llvm/CallingConv.h"
24#include "llvm/DerivedTypes.h"
25#include "llvm/Module.h"
26#include "llvm/Type.h"
27#include "llvm/Analysis/DebugInfo.h"
28#include "llvm/Assembly/Writer.h"
29#include "llvm/MC/MCAsmInfo.h"
30#include "llvm/MC/MCContext.h"
31#include "llvm/MC/MCExpr.h"
32#include "llvm/MC/MCSectionMachO.h"
33#include "llvm/MC/MCStreamer.h"
34#include "llvm/MC/MCSymbol.h"
35#include "llvm/CodeGen/MachineJumpTableInfo.h"
36#include "llvm/CodeGen/MachineModuleInfoImpls.h"
37#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
38#include "llvm/Target/Mangler.h"
39#include "llvm/Target/TargetOptions.h"
40#include "llvm/Support/COFF.h"
41#include "llvm/Support/Debug.h"
42#include "llvm/Support/ErrorHandling.h"
43#include "llvm/Support/TargetRegistry.h"
44#include "llvm/ADT/SmallString.h"
45using namespace llvm;
46
47//===----------------------------------------------------------------------===//
48// Primitive Helper Functions.
49//===----------------------------------------------------------------------===//
50
51/// runOnMachineFunction - Emit the function body.
52///
53bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
54  SetupMachineFunction(MF);
55
56  if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
57    bool Intrn = MF.getFunction()->hasInternalLinkage();
58    OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
59    OutStreamer.EmitCOFFSymbolStorageClass(Intrn ? COFF::IMAGE_SYM_CLASS_STATIC
60                                              : COFF::IMAGE_SYM_CLASS_EXTERNAL);
61    OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
62                                               << COFF::SCT_COMPLEX_TYPE_SHIFT);
63    OutStreamer.EndCOFFSymbolDef();
64  }
65
66  // Have common code print out the function header with linkage info etc.
67  EmitFunctionHeader();
68
69  // Emit the rest of the function body.
70  EmitFunctionBody();
71
72  // We didn't modify anything.
73  return false;
74}
75
76/// printSymbolOperand - Print a raw symbol reference operand.  This handles
77/// jump tables, constant pools, global address and external symbols, all of
78/// which print to a label with various suffixes for relocation types etc.
79void X86AsmPrinter::printSymbolOperand(const MachineOperand &MO,
80                                       raw_ostream &O) {
81  switch (MO.getType()) {
82  default: llvm_unreachable("unknown symbol type!");
83  case MachineOperand::MO_JumpTableIndex:
84    O << *GetJTISymbol(MO.getIndex());
85    break;
86  case MachineOperand::MO_ConstantPoolIndex:
87    O << *GetCPISymbol(MO.getIndex());
88    printOffset(MO.getOffset(), O);
89    break;
90  case MachineOperand::MO_GlobalAddress: {
91    const GlobalValue *GV = MO.getGlobal();
92
93    MCSymbol *GVSym;
94    if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
95      GVSym = GetSymbolWithGlobalValueBase(GV, "$stub");
96    else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
97             MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
98             MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
99      GVSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
100    else
101      GVSym = Mang->getSymbol(GV);
102
103    // Handle dllimport linkage.
104    if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
105      GVSym = OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName());
106
107    if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
108        MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) {
109      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
110      MachineModuleInfoImpl::StubValueTy &StubSym =
111        MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym);
112      if (StubSym.getPointer() == 0)
113        StubSym = MachineModuleInfoImpl::
114          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
115    } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){
116      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
117      MachineModuleInfoImpl::StubValueTy &StubSym =
118        MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry(Sym);
119      if (StubSym.getPointer() == 0)
120        StubSym = MachineModuleInfoImpl::
121          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
122    } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
123      MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
124      MachineModuleInfoImpl::StubValueTy &StubSym =
125        MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
126      if (StubSym.getPointer() == 0)
127        StubSym = MachineModuleInfoImpl::
128          StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
129    }
130
131    // If the name begins with a dollar-sign, enclose it in parens.  We do this
132    // to avoid having it look like an integer immediate to the assembler.
133    if (GVSym->getName()[0] != '$')
134      O << *GVSym;
135    else
136      O << '(' << *GVSym << ')';
137    printOffset(MO.getOffset(), O);
138    break;
139  }
140  case MachineOperand::MO_ExternalSymbol: {
141    const MCSymbol *SymToPrint;
142    if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
143      SmallString<128> TempNameStr;
144      TempNameStr += StringRef(MO.getSymbolName());
145      TempNameStr += StringRef("$stub");
146
147      MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
148      MachineModuleInfoImpl::StubValueTy &StubSym =
149        MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
150      if (StubSym.getPointer() == 0) {
151        TempNameStr.erase(TempNameStr.end()-5, TempNameStr.end());
152        StubSym = MachineModuleInfoImpl::
153          StubValueTy(OutContext.GetOrCreateSymbol(TempNameStr.str()),
154                      true);
155      }
156      SymToPrint = StubSym.getPointer();
157    } else {
158      SymToPrint = GetExternalSymbolSymbol(MO.getSymbolName());
159    }
160
161    // If the name begins with a dollar-sign, enclose it in parens.  We do this
162    // to avoid having it look like an integer immediate to the assembler.
163    if (SymToPrint->getName()[0] != '$')
164      O << *SymToPrint;
165    else
166      O << '(' << *SymToPrint << '(';
167    break;
168  }
169  }
170
171  switch (MO.getTargetFlags()) {
172  default:
173    llvm_unreachable("Unknown target flag on GV operand");
174  case X86II::MO_NO_FLAG:    // No flag.
175    break;
176  case X86II::MO_DARWIN_NONLAZY:
177  case X86II::MO_DLLIMPORT:
178  case X86II::MO_DARWIN_STUB:
179    // These affect the name of the symbol, not any suffix.
180    break;
181  case X86II::MO_GOT_ABSOLUTE_ADDRESS:
182    O << " + [.-" << *MF->getPICBaseSymbol() << ']';
183    break;
184  case X86II::MO_PIC_BASE_OFFSET:
185  case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
186  case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
187    O << '-' << *MF->getPICBaseSymbol();
188    break;
189  case X86II::MO_TLSGD:     O << "@TLSGD";     break;
190  case X86II::MO_GOTTPOFF:  O << "@GOTTPOFF";  break;
191  case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
192  case X86II::MO_TPOFF:     O << "@TPOFF";     break;
193  case X86II::MO_NTPOFF:    O << "@NTPOFF";    break;
194  case X86II::MO_GOTPCREL:  O << "@GOTPCREL";  break;
195  case X86II::MO_GOT:       O << "@GOT";       break;
196  case X86II::MO_GOTOFF:    O << "@GOTOFF";    break;
197  case X86II::MO_PLT:       O << "@PLT";       break;
198  case X86II::MO_TLVP:      O << "@TLVP";      break;
199  case X86II::MO_TLVP_PIC_BASE:
200    O << "@TLVP" << '-' << *MF->getPICBaseSymbol();
201    break;
202  case X86II::MO_SECREL:      O << "@SECREL";      break;
203  }
204}
205
206/// print_pcrel_imm - This is used to print an immediate value that ends up
207/// being encoded as a pc-relative value.  These print slightly differently, for
208/// example, a $ is not emitted.
209void X86AsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo,
210                                    raw_ostream &O) {
211  const MachineOperand &MO = MI->getOperand(OpNo);
212  switch (MO.getType()) {
213  default: llvm_unreachable("Unknown pcrel immediate operand");
214  case MachineOperand::MO_Register:
215    // pc-relativeness was handled when computing the value in the reg.
216    printOperand(MI, OpNo, O);
217    return;
218  case MachineOperand::MO_Immediate:
219    O << MO.getImm();
220    return;
221  case MachineOperand::MO_MachineBasicBlock:
222    O << *MO.getMBB()->getSymbol();
223    return;
224  case MachineOperand::MO_GlobalAddress:
225  case MachineOperand::MO_ExternalSymbol:
226    printSymbolOperand(MO, O);
227    return;
228  }
229}
230
231
232void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
233                                 raw_ostream &O, const char *Modifier) {
234  const MachineOperand &MO = MI->getOperand(OpNo);
235  switch (MO.getType()) {
236  default: llvm_unreachable("unknown operand type!");
237  case MachineOperand::MO_Register: {
238    O << '%';
239    unsigned Reg = MO.getReg();
240    if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
241      EVT VT = (strcmp(Modifier+6,"64") == 0) ?
242        MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
243                    ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
244      Reg = getX86SubSuperRegister(Reg, VT);
245    }
246    O << X86ATTInstPrinter::getRegisterName(Reg);
247    return;
248  }
249
250  case MachineOperand::MO_Immediate:
251    O << '$' << MO.getImm();
252    return;
253
254  case MachineOperand::MO_JumpTableIndex:
255  case MachineOperand::MO_ConstantPoolIndex:
256  case MachineOperand::MO_GlobalAddress:
257  case MachineOperand::MO_ExternalSymbol: {
258    O << '$';
259    printSymbolOperand(MO, O);
260    break;
261  }
262  }
263}
264
265void X86AsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op,
266                               raw_ostream &O) {
267  unsigned char value = MI->getOperand(Op).getImm();
268  assert(value <= 7 && "Invalid ssecc argument!");
269  switch (value) {
270  case    0: O << "eq"; break;
271  case    1: O << "lt"; break;
272  case    2: O << "le"; break;
273  case    3: O << "unord"; break;
274  case    4: O << "neq"; break;
275  case    5: O << "nlt"; break;
276  case    6: O << "nle"; break;
277  case    7: O << "ord"; break;
278  case    8: O << "eq_uq"; break;
279  case    9: O << "nge"; break;
280  case  0xa: O << "ngt"; break;
281  case  0xb: O << "false"; break;
282  case  0xc: O << "neq_oq"; break;
283  case  0xd: O << "ge"; break;
284  case  0xe: O << "gt"; break;
285  case  0xf: O << "true"; break;
286  case 0x10: O << "eq_os"; break;
287  case 0x11: O << "lt_oq"; break;
288  case 0x12: O << "le_oq"; break;
289  case 0x13: O << "unord_s"; break;
290  case 0x14: O << "neq_us"; break;
291  case 0x15: O << "nlt_uq"; break;
292  case 0x16: O << "nle_uq"; break;
293  case 0x17: O << "ord_s"; break;
294  case 0x18: O << "eq_us"; break;
295  case 0x19: O << "nge_uq"; break;
296  case 0x1a: O << "ngt_uq"; break;
297  case 0x1b: O << "false_os"; break;
298  case 0x1c: O << "neq_os"; break;
299  case 0x1d: O << "ge_oq"; break;
300  case 0x1e: O << "gt_oq"; break;
301  case 0x1f: O << "true_us"; break;
302  }
303}
304
305void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
306                                         raw_ostream &O, const char *Modifier) {
307  const MachineOperand &BaseReg  = MI->getOperand(Op);
308  const MachineOperand &IndexReg = MI->getOperand(Op+2);
309  const MachineOperand &DispSpec = MI->getOperand(Op+3);
310
311  // If we really don't want to print out (rip), don't.
312  bool HasBaseReg = BaseReg.getReg() != 0;
313  if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
314      BaseReg.getReg() == X86::RIP)
315    HasBaseReg = false;
316
317  // HasParenPart - True if we will print out the () part of the mem ref.
318  bool HasParenPart = IndexReg.getReg() || HasBaseReg;
319
320  if (DispSpec.isImm()) {
321    int DispVal = DispSpec.getImm();
322    if (DispVal || !HasParenPart)
323      O << DispVal;
324  } else {
325    assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
326           DispSpec.isJTI() || DispSpec.isSymbol());
327    printSymbolOperand(MI->getOperand(Op+3), O);
328  }
329
330  if (Modifier && strcmp(Modifier, "H") == 0)
331    O << "+8";
332
333  if (HasParenPart) {
334    assert(IndexReg.getReg() != X86::ESP &&
335           "X86 doesn't allow scaling by ESP");
336
337    O << '(';
338    if (HasBaseReg)
339      printOperand(MI, Op, O, Modifier);
340
341    if (IndexReg.getReg()) {
342      O << ',';
343      printOperand(MI, Op+2, O, Modifier);
344      unsigned ScaleVal = MI->getOperand(Op+1).getImm();
345      if (ScaleVal != 1)
346        O << ',' << ScaleVal;
347    }
348    O << ')';
349  }
350}
351
352void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
353                                      raw_ostream &O, const char *Modifier) {
354  assert(isMem(MI, Op) && "Invalid memory reference!");
355  const MachineOperand &Segment = MI->getOperand(Op+4);
356  if (Segment.getReg()) {
357    printOperand(MI, Op+4, O, Modifier);
358    O << ':';
359  }
360  printLeaMemReference(MI, Op, O, Modifier);
361}
362
363void X86AsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op,
364                                  raw_ostream &O) {
365  O << *MF->getPICBaseSymbol() << '\n';
366  O << *MF->getPICBaseSymbol() << ':';
367}
368
369bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
370                                      raw_ostream &O) {
371  unsigned Reg = MO.getReg();
372  switch (Mode) {
373  default: return true;  // Unknown mode.
374  case 'b': // Print QImode register
375    Reg = getX86SubSuperRegister(Reg, MVT::i8);
376    break;
377  case 'h': // Print QImode high register
378    Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
379    break;
380  case 'w': // Print HImode register
381    Reg = getX86SubSuperRegister(Reg, MVT::i16);
382    break;
383  case 'k': // Print SImode register
384    Reg = getX86SubSuperRegister(Reg, MVT::i32);
385    break;
386  case 'q': // Print DImode register
387    Reg = getX86SubSuperRegister(Reg, MVT::i64);
388    break;
389  }
390
391  O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
392  return false;
393}
394
395/// PrintAsmOperand - Print out an operand for an inline asm expression.
396///
397bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
398                                    unsigned AsmVariant,
399                                    const char *ExtraCode, raw_ostream &O) {
400  // Does this asm operand have a single letter operand modifier?
401  if (ExtraCode && ExtraCode[0]) {
402    if (ExtraCode[1] != 0) return true; // Unknown modifier.
403
404    const MachineOperand &MO = MI->getOperand(OpNo);
405
406    switch (ExtraCode[0]) {
407    default: return true;  // Unknown modifier.
408    case 'a': // This is an address.  Currently only 'i' and 'r' are expected.
409      if (MO.isImm()) {
410        O << MO.getImm();
411        return false;
412      }
413      if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
414        printSymbolOperand(MO, O);
415        if (Subtarget->isPICStyleRIPRel())
416          O << "(%rip)";
417        return false;
418      }
419      if (MO.isReg()) {
420        O << '(';
421        printOperand(MI, OpNo, O);
422        O << ')';
423        return false;
424      }
425      return true;
426
427    case 'c': // Don't print "$" before a global var name or constant.
428      if (MO.isImm())
429        O << MO.getImm();
430      else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
431        printSymbolOperand(MO, O);
432      else
433        printOperand(MI, OpNo, O);
434      return false;
435
436    case 'A': // Print '*' before a register (it must be a register)
437      if (MO.isReg()) {
438        O << '*';
439        printOperand(MI, OpNo, O);
440        return false;
441      }
442      return true;
443
444    case 'b': // Print QImode register
445    case 'h': // Print QImode high register
446    case 'w': // Print HImode register
447    case 'k': // Print SImode register
448    case 'q': // Print DImode register
449      if (MO.isReg())
450        return printAsmMRegister(MO, ExtraCode[0], O);
451      printOperand(MI, OpNo, O);
452      return false;
453
454    case 'P': // This is the operand of a call, treat specially.
455      print_pcrel_imm(MI, OpNo, O);
456      return false;
457
458    case 'n':  // Negate the immediate or print a '-' before the operand.
459      // Note: this is a temporary solution. It should be handled target
460      // independently as part of the 'MC' work.
461      if (MO.isImm()) {
462        O << -MO.getImm();
463        return false;
464      }
465      O << '-';
466    }
467  }
468
469  printOperand(MI, OpNo, O);
470  return false;
471}
472
473bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
474                                          unsigned OpNo, unsigned AsmVariant,
475                                          const char *ExtraCode,
476                                          raw_ostream &O) {
477  if (ExtraCode && ExtraCode[0]) {
478    if (ExtraCode[1] != 0) return true; // Unknown modifier.
479
480    switch (ExtraCode[0]) {
481    default: return true;  // Unknown modifier.
482    case 'b': // Print QImode register
483    case 'h': // Print QImode high register
484    case 'w': // Print HImode register
485    case 'k': // Print SImode register
486    case 'q': // Print SImode register
487      // These only apply to registers, ignore on mem.
488      break;
489    case 'H':
490      printMemReference(MI, OpNo, O, "H");
491      return false;
492    case 'P': // Don't print @PLT, but do print as memory.
493      printMemReference(MI, OpNo, O, "no-rip");
494      return false;
495    }
496  }
497  printMemReference(MI, OpNo, O);
498  return false;
499}
500
501void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
502  if (Subtarget->isTargetEnvMacho())
503    OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
504}
505
506
507void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
508  if (Subtarget->isTargetEnvMacho()) {
509    // All darwin targets use mach-o.
510    MachineModuleInfoMachO &MMIMacho =
511      MMI->getObjFileInfo<MachineModuleInfoMachO>();
512
513    // Output stubs for dynamically-linked functions.
514    MachineModuleInfoMachO::SymbolListTy Stubs;
515
516    Stubs = MMIMacho.GetFnStubList();
517    if (!Stubs.empty()) {
518      const MCSection *TheSection =
519        OutContext.getMachOSection("__IMPORT", "__jump_table",
520                                   MCSectionMachO::S_SYMBOL_STUBS |
521                                   MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
522                                   MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
523                                   5, SectionKind::getMetadata());
524      OutStreamer.SwitchSection(TheSection);
525
526      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
527        // L_foo$stub:
528        OutStreamer.EmitLabel(Stubs[i].first);
529        //   .indirect_symbol _foo
530        OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
531                                        MCSA_IndirectSymbol);
532        // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
533        const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
534        OutStreamer.EmitBytes(StringRef(HltInsts, 5), 0/*addrspace*/);
535      }
536
537      Stubs.clear();
538      OutStreamer.AddBlankLine();
539    }
540
541    // Output stubs for external and common global variables.
542    Stubs = MMIMacho.GetGVStubList();
543    if (!Stubs.empty()) {
544      const MCSection *TheSection =
545        OutContext.getMachOSection("__IMPORT", "__pointers",
546                                   MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
547                                   SectionKind::getMetadata());
548      OutStreamer.SwitchSection(TheSection);
549
550      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
551        // L_foo$non_lazy_ptr:
552        OutStreamer.EmitLabel(Stubs[i].first);
553        // .indirect_symbol _foo
554        MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
555        OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
556                                        MCSA_IndirectSymbol);
557        // .long 0
558        if (MCSym.getInt())
559          // External to current translation unit.
560          OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
561        else
562          // Internal to current translation unit.
563          //
564          // When we place the LSDA into the TEXT section, the type info
565          // pointers need to be indirect and pc-rel. We accomplish this by
566          // using NLPs.  However, sometimes the types are local to the file. So
567          // we need to fill in the value for the NLP in those cases.
568          OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
569                                                        OutContext),
570                                4/*size*/, 0/*addrspace*/);
571      }
572      Stubs.clear();
573      OutStreamer.AddBlankLine();
574    }
575
576    Stubs = MMIMacho.GetHiddenGVStubList();
577    if (!Stubs.empty()) {
578      OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
579      EmitAlignment(2);
580
581      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
582        // L_foo$non_lazy_ptr:
583        OutStreamer.EmitLabel(Stubs[i].first);
584        // .long _foo
585        OutStreamer.EmitValue(MCSymbolRefExpr::
586                              Create(Stubs[i].second.getPointer(),
587                                     OutContext),
588                              4/*size*/, 0/*addrspace*/);
589      }
590      Stubs.clear();
591      OutStreamer.AddBlankLine();
592    }
593
594    // Funny Darwin hack: This flag tells the linker that no global symbols
595    // contain code that falls through to other global symbols (e.g. the obvious
596    // implementation of multiple entry points).  If this doesn't occur, the
597    // linker can safely perform dead code stripping.  Since LLVM never
598    // generates code that does this, it is always safe to set.
599    OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
600  }
601
602  if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
603      MMI->callsExternalVAFunctionWithFloatingPointArguments()) {
604    StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
605    MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
606    OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
607  }
608
609  if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
610    X86COFFMachineModuleInfo &COFFMMI =
611      MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
612
613    // Emit type information for external functions
614    typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
615    for (externals_iterator I = COFFMMI.externals_begin(),
616                            E = COFFMMI.externals_end();
617                            I != E; ++I) {
618      OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
619      OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
620      OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
621                                               << COFF::SCT_COMPLEX_TYPE_SHIFT);
622      OutStreamer.EndCOFFSymbolDef();
623    }
624
625    // Necessary for dllexport support
626    std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
627
628    const TargetLoweringObjectFileCOFF &TLOFCOFF =
629      static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());
630
631    for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
632      if (I->hasDLLExportLinkage())
633        DLLExportedFns.push_back(Mang->getSymbol(I));
634
635    for (Module::const_global_iterator I = M.global_begin(),
636           E = M.global_end(); I != E; ++I)
637      if (I->hasDLLExportLinkage())
638        DLLExportedGlobals.push_back(Mang->getSymbol(I));
639
640    // Output linker support code for dllexported globals on windows.
641    if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
642      OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
643      SmallString<128> name;
644      for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
645        if (Subtarget->isTargetWindows())
646          name = " /EXPORT:";
647        else
648          name = " -export:";
649        name += DLLExportedGlobals[i]->getName();
650        if (Subtarget->isTargetWindows())
651          name += ",DATA";
652        else
653        name += ",data";
654        OutStreamer.EmitBytes(name, 0);
655      }
656
657      for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
658        if (Subtarget->isTargetWindows())
659          name = " /EXPORT:";
660        else
661          name = " -export:";
662        name += DLLExportedFns[i]->getName();
663        OutStreamer.EmitBytes(name, 0);
664      }
665    }
666  }
667
668  if (Subtarget->isTargetELF()) {
669    const TargetLoweringObjectFileELF &TLOFELF =
670      static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());
671
672    MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
673
674    // Output stubs for external and common global variables.
675    MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
676    if (!Stubs.empty()) {
677      OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
678      const TargetData *TD = TM.getTargetData();
679
680      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
681        OutStreamer.EmitLabel(Stubs[i].first);
682        OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
683                                    TD->getPointerSize(), 0);
684      }
685      Stubs.clear();
686    }
687  }
688}
689
690MachineLocation
691X86AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
692  MachineLocation Location;
693  assert (MI->getNumOperands() == 7 && "Invalid no. of machine operands!");
694  // Frame address.  Currently handles register +- offset only.
695
696  if (MI->getOperand(0).isReg() && MI->getOperand(3).isImm())
697    Location.set(MI->getOperand(0).getReg(), MI->getOperand(3).getImm());
698  else {
699    DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
700  }
701  return Location;
702}
703
704void X86AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
705                                           raw_ostream &O) {
706  // Only the target-dependent form of DBG_VALUE should get here.
707  // Referencing the offset and metadata as NOps-2 and NOps-1 is
708  // probably portable to other targets; frame pointer location is not.
709  unsigned NOps = MI->getNumOperands();
710  assert(NOps==7);
711  O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
712  // cast away const; DIetc do not take const operands for some reason.
713  DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
714  if (V.getContext().isSubprogram())
715    O << DISubprogram(V.getContext()).getDisplayName() << ":";
716  O << V.getName();
717  O << " <- ";
718  // Frame address.  Currently handles register +- offset only.
719  O << '[';
720  if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg())
721    printOperand(MI, 0, O);
722  else
723    O << "undef";
724  O << '+'; printOperand(MI, 3, O);
725  O << ']';
726  O << "+";
727  printOperand(MI, NOps-2, O);
728}
729
730
731
732//===----------------------------------------------------------------------===//
733// Target Registry Stuff
734//===----------------------------------------------------------------------===//
735
736// Force static initialization.
737extern "C" void LLVMInitializeX86AsmPrinter() {
738  RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
739  RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
740}
741