lib/Target/X86/X86AsmPrinter.cpp

   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/Support/COFF.h"
  39 #include "llvm/Support/Debug.h"
  40 #include "llvm/Support/ErrorHandling.h"
  41 #include "llvm/Target/Mangler.h"
  42 #include "llvm/Target/TargetOptions.h"
  43 #include "llvm/Target/TargetRegistry.h"
  44 #include "llvm/ADT/SmallString.h"
  45 using namespace llvm;
  46
  47 //===----------------------------------------------------------------------===//
  48 // Primitive Helper Functions.
  49 //===----------------------------------------------------------------------===//
  50
  51 /// runOnMachineFunction - Emit the function body.
  52 ///
  53 bool 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.
  79 void 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   }
 203 }
 204
 205 /// print_pcrel_imm - This is used to print an immediate value that ends up
 206 /// being encoded as a pc-relative value.  These print slightly differently, for
 207 /// example, a $ is not emitted.
 208 void X86AsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo,
 209                                     raw_ostream &O) {
 210   const MachineOperand &MO = MI->getOperand(OpNo);
 211   switch (MO.getType()) {
 212   default: llvm_unreachable("Unknown pcrel immediate operand");
 213   case MachineOperand::MO_Register:
 214     // pc-relativeness was handled when computing the value in the reg.
 215     printOperand(MI, OpNo, O);
 216     return;
 217   case MachineOperand::MO_Immediate:
 218     O << MO.getImm();
 219     return;
 220   case MachineOperand::MO_MachineBasicBlock:
 221     O << *MO.getMBB()->getSymbol();
 222     return;
 223   case MachineOperand::MO_GlobalAddress:
 224   case MachineOperand::MO_ExternalSymbol:
 225     printSymbolOperand(MO, O);
 226     return;
 227   }
 228 }
 229
 230
 231 void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
 232                                  raw_ostream &O, const char *Modifier) {
 233   const MachineOperand &MO = MI->getOperand(OpNo);
 234   switch (MO.getType()) {
 235   default: llvm_unreachable("unknown operand type!");
 236   case MachineOperand::MO_Register: {
 237     O << '%';
 238     unsigned Reg = MO.getReg();
 239     if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
 240       EVT VT = (strcmp(Modifier+6,"64") == 0) ?
 241         MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
 242                     ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
 243       Reg = getX86SubSuperRegister(Reg, VT);
 244     }
 245     O << X86ATTInstPrinter::getRegisterName(Reg);
 246     return;
 247   }
 248
 249   case MachineOperand::MO_Immediate:
 250     O << '$' << MO.getImm();
 251     return;
 252
 253   case MachineOperand::MO_JumpTableIndex:
 254   case MachineOperand::MO_ConstantPoolIndex:
 255   case MachineOperand::MO_GlobalAddress:
 256   case MachineOperand::MO_ExternalSymbol: {
 257     O << '$';
 258     printSymbolOperand(MO, O);
 259     break;
 260   }
 261   }
 262 }
 263
 264 void X86AsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op,
 265                                raw_ostream &O) {
 266   unsigned char value = MI->getOperand(Op).getImm();
 267   assert(value <= 7 && "Invalid ssecc argument!");
 268   switch (value) {
 269   case 0: O << "eq"; break;
 270   case 1: O << "lt"; break;
 271   case 2: O << "le"; break;
 272   case 3: O << "unord"; break;
 273   case 4: O << "neq"; break;
 274   case 5: O << "nlt"; break;
 275   case 6: O << "nle"; break;
 276   case 7: O << "ord"; break;
 277   }
 278 }
 279
 280 void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
 281                                          raw_ostream &O, const char *Modifier) {
 282   const MachineOperand &BaseReg  = MI->getOperand(Op);
 283   const MachineOperand &IndexReg = MI->getOperand(Op+2);
 284   const MachineOperand &DispSpec = MI->getOperand(Op+3);
 285
 286   // If we really don't want to print out (rip), don't.
 287   bool HasBaseReg = BaseReg.getReg() != 0;
 288   if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
 289       BaseReg.getReg() == X86::RIP)
 290     HasBaseReg = false;
 291
 292   // HasParenPart - True if we will print out the () part of the mem ref.
 293   bool HasParenPart = IndexReg.getReg() || HasBaseReg;
 294
 295   if (DispSpec.isImm()) {
 296     int DispVal = DispSpec.getImm();
 297     if (DispVal || !HasParenPart)
 298       O << DispVal;
 299   } else {
 300     assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
 301            DispSpec.isJTI() || DispSpec.isSymbol());
 302     printSymbolOperand(MI->getOperand(Op+3), O);
 303   }
 304
 305   if (Modifier && strcmp(Modifier, "H") == 0)
 306     O << "+8";
 307
 308   if (HasParenPart) {
 309     assert(IndexReg.getReg() != X86::ESP &&
 310            "X86 doesn't allow scaling by ESP");
 311
 312     O << '(';
 313     if (HasBaseReg)
 314       printOperand(MI, Op, O, Modifier);
 315
 316     if (IndexReg.getReg()) {
 317       O << ',';
 318       printOperand(MI, Op+2, O, Modifier);
 319       unsigned ScaleVal = MI->getOperand(Op+1).getImm();
 320       if (ScaleVal != 1)
 321         O << ',' << ScaleVal;
 322     }
 323     O << ')';
 324   }
 325 }
 326
 327 void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
 328                                       raw_ostream &O, const char *Modifier) {
 329   assert(isMem(MI, Op) && "Invalid memory reference!");
 330   const MachineOperand &Segment = MI->getOperand(Op+4);
 331   if (Segment.getReg()) {
 332     printOperand(MI, Op+4, O, Modifier);
 333     O << ':';
 334   }
 335   printLeaMemReference(MI, Op, O, Modifier);
 336 }
 337
 338 void X86AsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op,
 339                                   raw_ostream &O) {
 340   O << *MF->getPICBaseSymbol() << '\n';
 341   O << *MF->getPICBaseSymbol() << ':';
 342 }
 343
 344 bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
 345                                       raw_ostream &O) {
 346   unsigned Reg = MO.getReg();
 347   switch (Mode) {
 348   default: return true;  // Unknown mode.
 349   case 'b': // Print QImode register
 350     Reg = getX86SubSuperRegister(Reg, MVT::i8);
 351     break;
 352   case 'h': // Print QImode high register
 353     Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
 354     break;
 355   case 'w': // Print HImode register
 356     Reg = getX86SubSuperRegister(Reg, MVT::i16);
 357     break;
 358   case 'k': // Print SImode register
 359     Reg = getX86SubSuperRegister(Reg, MVT::i32);
 360     break;
 361   case 'q': // Print DImode register
 362     Reg = getX86SubSuperRegister(Reg, MVT::i64);
 363     break;
 364   }
 365
 366   O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
 367   return false;
 368 }
 369
 370 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 371 ///
 372 bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 373                                     unsigned AsmVariant,
 374                                     const char *ExtraCode, raw_ostream &O) {
 375   // Does this asm operand have a single letter operand modifier?
 376   if (ExtraCode && ExtraCode[0]) {
 377     if (ExtraCode[1] != 0) return true; // Unknown modifier.
 378
 379     const MachineOperand &MO = MI->getOperand(OpNo);
 380
 381     switch (ExtraCode[0]) {
 382     default: return true;  // Unknown modifier.
 383     case 'a': // This is an address.  Currently only 'i' and 'r' are expected.
 384       if (MO.isImm()) {
 385         O << MO.getImm();
 386         return false;
 387       }
 388       if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
 389         printSymbolOperand(MO, O);
 390         if (Subtarget->isPICStyleRIPRel())
 391           O << "(%rip)";
 392         return false;
 393       }
 394       if (MO.isReg()) {
 395         O << '(';
 396         printOperand(MI, OpNo, O);
 397         O << ')';
 398         return false;
 399       }
 400       return true;
 401
 402     case 'c': // Don't print "$" before a global var name or constant.
 403       if (MO.isImm())
 404         O << MO.getImm();
 405       else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
 406         printSymbolOperand(MO, O);
 407       else
 408         printOperand(MI, OpNo, O);
 409       return false;
 410
 411     case 'A': // Print '*' before a register (it must be a register)
 412       if (MO.isReg()) {
 413         O << '*';
 414         printOperand(MI, OpNo, O);
 415         return false;
 416       }
 417       return true;
 418
 419     case 'b': // Print QImode register
 420     case 'h': // Print QImode high register
 421     case 'w': // Print HImode register
 422     case 'k': // Print SImode register
 423     case 'q': // Print DImode register
 424       if (MO.isReg())
 425         return printAsmMRegister(MO, ExtraCode[0], O);
 426       printOperand(MI, OpNo, O);
 427       return false;
 428
 429     case 'P': // This is the operand of a call, treat specially.
 430       print_pcrel_imm(MI, OpNo, O);
 431       return false;
 432
 433     case 'n':  // Negate the immediate or print a '-' before the operand.
 434       // Note: this is a temporary solution. It should be handled target
 435       // independently as part of the 'MC' work.
 436       if (MO.isImm()) {
 437         O << -MO.getImm();
 438         return false;
 439       }
 440       O << '-';
 441     }
 442   }
 443
 444   printOperand(MI, OpNo, O);
 445   return false;
 446 }
 447
 448 bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 449                                           unsigned OpNo, unsigned AsmVariant,
 450                                           const char *ExtraCode,
 451                                           raw_ostream &O) {
 452   if (ExtraCode && ExtraCode[0]) {
 453     if (ExtraCode[1] != 0) return true; // Unknown modifier.
 454
 455     switch (ExtraCode[0]) {
 456     default: return true;  // Unknown modifier.
 457     case 'b': // Print QImode register
 458     case 'h': // Print QImode high register
 459     case 'w': // Print HImode register
 460     case 'k': // Print SImode register
 461     case 'q': // Print SImode register
 462       // These only apply to registers, ignore on mem.
 463       break;
 464     case 'H':
 465       printMemReference(MI, OpNo, O, "H");
 466       return false;
 467     case 'P': // Don't print @PLT, but do print as memory.
 468       printMemReference(MI, OpNo, O, "no-rip");
 469       return false;
 470     }
 471   }
 472   printMemReference(MI, OpNo, O);
 473   return false;
 474 }
 475
 476 void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
 477   if (Subtarget->isTargetEnvMacho())
 478     OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
 479 }
 480
 481
 482 void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
 483   if (Subtarget->isTargetEnvMacho()) {
 484     // All darwin targets use mach-o.
 485     MachineModuleInfoMachO &MMIMacho =
 486       MMI->getObjFileInfo<MachineModuleInfoMachO>();
 487
 488     // Output stubs for dynamically-linked functions.
 489     MachineModuleInfoMachO::SymbolListTy Stubs;
 490
 491     Stubs = MMIMacho.GetFnStubList();
 492     if (!Stubs.empty()) {
 493       const MCSection *TheSection =
 494         OutContext.getMachOSection("__IMPORT", "__jump_table",
 495                                    MCSectionMachO::S_SYMBOL_STUBS |
 496                                    MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
 497                                    MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
 498                                    5, SectionKind::getMetadata());
 499       OutStreamer.SwitchSection(TheSection);
 500
 501       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
 502         // L_foo$stub:
 503         OutStreamer.EmitLabel(Stubs[i].first);
 504         //   .indirect_symbol _foo
 505         OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
 506                                         MCSA_IndirectSymbol);
 507         // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4 = -12.
 508         const char HltInsts[] = { -12, -12, -12, -12, -12 };
 509         OutStreamer.EmitBytes(StringRef(HltInsts, 5), 0/*addrspace*/);
 510       }
 511
 512       Stubs.clear();
 513       OutStreamer.AddBlankLine();
 514     }
 515
 516     // Output stubs for external and common global variables.
 517     Stubs = MMIMacho.GetGVStubList();
 518     if (!Stubs.empty()) {
 519       const MCSection *TheSection =
 520         OutContext.getMachOSection("__IMPORT", "__pointers",
 521                                    MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
 522                                    SectionKind::getMetadata());
 523       OutStreamer.SwitchSection(TheSection);
 524
 525       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
 526         // L_foo$non_lazy_ptr:
 527         OutStreamer.EmitLabel(Stubs[i].first);
 528         // .indirect_symbol _foo
 529         MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
 530         OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
 531                                         MCSA_IndirectSymbol);
 532         // .long 0
 533         if (MCSym.getInt())
 534           // External to current translation unit.
 535           OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
 536         else
 537           // Internal to current translation unit.
 538           //
 539           // When we place the LSDA into the TEXT section, the type info
 540           // pointers need to be indirect and pc-rel. We accomplish this by
 541           // using NLPs.  However, sometimes the types are local to the file. So
 542           // we need to fill in the value for the NLP in those cases.
 543           OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
 544                                                         OutContext),
 545                                 4/*size*/, 0/*addrspace*/);
 546       }
 547       Stubs.clear();
 548       OutStreamer.AddBlankLine();
 549     }
 550
 551     Stubs = MMIMacho.GetHiddenGVStubList();
 552     if (!Stubs.empty()) {
 553       OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
 554       EmitAlignment(2);
 555
 556       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
 557         // L_foo$non_lazy_ptr:
 558         OutStreamer.EmitLabel(Stubs[i].first);
 559         // .long _foo
 560         OutStreamer.EmitValue(MCSymbolRefExpr::
 561                               Create(Stubs[i].second.getPointer(),
 562                                      OutContext),
 563                               4/*size*/, 0/*addrspace*/);
 564       }
 565       Stubs.clear();
 566       OutStreamer.AddBlankLine();
 567     }
 568
 569     // Funny Darwin hack: This flag tells the linker that no global symbols
 570     // contain code that falls through to other global symbols (e.g. the obvious
 571     // implementation of multiple entry points).  If this doesn't occur, the
 572     // linker can safely perform dead code stripping.  Since LLVM never
 573     // generates code that does this, it is always safe to set.
 574     OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
 575   }
 576
 577   if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
 578       MMI->callsExternalVAFunctionWithFloatingPointArguments()) {
 579     StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
 580     MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
 581     OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
 582   }
 583
 584   if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
 585     X86COFFMachineModuleInfo &COFFMMI =
 586       MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
 587
 588     // Emit type information for external functions
 589     typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
 590     for (externals_iterator I = COFFMMI.externals_begin(),
 591                             E = COFFMMI.externals_end();
 592                             I != E; ++I) {
 593       OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
 594       OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
 595       OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
 596                                                << COFF::SCT_COMPLEX_TYPE_SHIFT);
 597       OutStreamer.EndCOFFSymbolDef();
 598     }
 599
 600     // Necessary for dllexport support
 601     std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
 602
 603     const TargetLoweringObjectFileCOFF &TLOFCOFF =
 604       static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());
 605
 606     for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
 607       if (I->hasDLLExportLinkage())
 608         DLLExportedFns.push_back(Mang->getSymbol(I));
 609
 610     for (Module::const_global_iterator I = M.global_begin(),
 611            E = M.global_end(); I != E; ++I)
 612       if (I->hasDLLExportLinkage())
 613         DLLExportedGlobals.push_back(Mang->getSymbol(I));
 614
 615     // Output linker support code for dllexported globals on windows.
 616     if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
 617       OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
 618       SmallString<128> name;
 619       for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
 620         if (Subtarget->isTargetWindows())
 621           name = " /EXPORT:";
 622         else
 623           name = " -export:";
 624         name += DLLExportedGlobals[i]->getName();
 625         if (Subtarget->isTargetWindows())
 626           name += ",DATA";
 627         else
 628         name += ",data";
 629         OutStreamer.EmitBytes(name, 0);
 630       }
 631
 632       for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
 633         if (Subtarget->isTargetWindows())
 634           name = " /EXPORT:";
 635         else
 636           name = " -export:";
 637         name += DLLExportedFns[i]->getName();
 638         OutStreamer.EmitBytes(name, 0);
 639       }
 640     }
 641   }
 642
 643   if (Subtarget->isTargetELF()) {
 644     const TargetLoweringObjectFileELF &TLOFELF =
 645       static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());
 646
 647     MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
 648
 649     // Output stubs for external and common global variables.
 650     MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
 651     if (!Stubs.empty()) {
 652       OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
 653       const TargetData *TD = TM.getTargetData();
 654
 655       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
 656         OutStreamer.EmitLabel(Stubs[i].first);
 657         OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
 658                                     TD->getPointerSize(), 0);
 659       }
 660       Stubs.clear();
 661     }
 662   }
 663 }
 664
 665 MachineLocation
 666 X86AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
 667   MachineLocation Location;
 668   assert (MI->getNumOperands() == 7 && "Invalid no. of machine operands!");
 669   // Frame address.  Currently handles register +- offset only.
 670
 671   if (MI->getOperand(0).isReg() && MI->getOperand(3).isImm())
 672     Location.set(MI->getOperand(0).getReg(), MI->getOperand(3).getImm());
 673   else {
 674     DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
 675   }
 676   return Location;
 677 }
 678
 679 void X86AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
 680                                            raw_ostream &O) {
 681   // Only the target-dependent form of DBG_VALUE should get here.
 682   // Referencing the offset and metadata as NOps-2 and NOps-1 is
 683   // probably portable to other targets; frame pointer location is not.
 684   unsigned NOps = MI->getNumOperands();
 685   assert(NOps==7);
 686   O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
 687   // cast away const; DIetc do not take const operands for some reason.
 688   DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
 689   if (V.getContext().isSubprogram())
 690     O << DISubprogram(V.getContext()).getDisplayName() << ":";
 691   O << V.getName();
 692   O << " <- ";
 693   // Frame address.  Currently handles register +- offset only.
 694   O << '[';
 695   if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg())
 696     printOperand(MI, 0, O);
 697   else
 698     O << "undef";
 699   O << '+'; printOperand(MI, 3, O);
 700   O << ']';
 701   O << "+";
 702   printOperand(MI, NOps-2, O);
 703 }
 704
 705
 706
 707 //===----------------------------------------------------------------------===//
 708 // Target Registry Stuff
 709 //===----------------------------------------------------------------------===//
 710
 711 static MCInstPrinter *createX86MCInstPrinter(const Target &T,
 712                                              TargetMachine &TM,
 713                                              unsigned SyntaxVariant,
 714                                              const MCAsmInfo &MAI) {
 715   if (SyntaxVariant == 0)
 716     return new X86ATTInstPrinter(TM, MAI);
 717   if (SyntaxVariant == 1)
 718     return new X86IntelInstPrinter(TM, MAI);
 719   return 0;
 720 }
 721
 722 // Force static initialization.
 723 extern "C" void LLVMInitializeX86AsmPrinter() {
 724   RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
 725   RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
 726
 727   TargetRegistry::RegisterMCInstPrinter(TheX86_32Target,createX86MCInstPrinter);
 728   TargetRegistry::RegisterMCInstPrinter(TheX86_64Target,createX86MCInstPrinter);
 729 }