lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp

   1 //===-- X86ATTAsmPrinter.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 AT&T format assembly
  12 // language. This printer is the output mechanism used by `llc'.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #define DEBUG_TYPE "asm-printer"
  17 #include "X86ATTAsmPrinter.h"
  18 #include "X86.h"
  19 #include "X86COFF.h"
  20 #include "X86MachineFunctionInfo.h"
  21 #include "X86TargetMachine.h"
  22 #include "llvm/CallingConv.h"
  23 #include "llvm/DerivedTypes.h"
  24 #include "llvm/Module.h"
  25 #include "llvm/Type.h"
  26 #include "llvm/ADT/Statistic.h"
  27 #include "llvm/ADT/StringExtras.h"
  28 #include "llvm/Assembly/Writer.h"
  29 #include "llvm/MC/MCStreamer.h"
  30 #include "llvm/MC/MCSectionMachO.h"
  31 #include "llvm/CodeGen/MachineJumpTableInfo.h"
  32 #include "llvm/Support/CommandLine.h"
  33 #include "llvm/Support/ErrorHandling.h"
  34 #include "llvm/Support/FormattedStream.h"
  35 #include "llvm/Support/Mangler.h"
  36 #include "llvm/MC/MCAsmInfo.h"
  37 #include "llvm/Target/TargetLoweringObjectFile.h"
  38 #include "llvm/Target/TargetOptions.h"
  39 using namespace llvm;
  40
  41 STATISTIC(EmittedInsts, "Number of machine instrs printed");
  42
  43 static cl::opt<bool> NewAsmPrinter("experimental-asm-printer",
  44                                    cl::Hidden, cl::init(true));
  45
  46 //===----------------------------------------------------------------------===//
  47 // Primitive Helper Functions.
  48 //===----------------------------------------------------------------------===//
  49
  50 void X86ATTAsmPrinter::PrintPICBaseSymbol() const {
  51   // FIXME: the actual label generated doesn't matter here!  Just mangle in
  52   // something unique (the function number) with Private prefix.
  53   if (Subtarget->isTargetDarwin())
  54     O << "\"L" << getFunctionNumber() << "$pb\"";
  55   else {
  56     assert(Subtarget->isTargetELF() && "Don't know how to print PIC label!");
  57     O << ".Lllvm$" << getFunctionNumber() << ".$piclabel";
  58   }
  59 }
  60
  61 static X86MachineFunctionInfo calculateFunctionInfo(const Function *F,
  62                                                     const TargetData *TD) {
  63   X86MachineFunctionInfo Info;
  64   uint64_t Size = 0;
  65
  66   switch (F->getCallingConv()) {
  67   case CallingConv::X86_StdCall:
  68     Info.setDecorationStyle(StdCall);
  69     break;
  70   case CallingConv::X86_FastCall:
  71     Info.setDecorationStyle(FastCall);
  72     break;
  73   default:
  74     return Info;
  75   }
  76
  77   unsigned argNum = 1;
  78   for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
  79        AI != AE; ++AI, ++argNum) {
  80     const Type* Ty = AI->getType();
  81
  82     // 'Dereference' type in case of byval parameter attribute
  83     if (F->paramHasAttr(argNum, Attribute::ByVal))
  84       Ty = cast<PointerType>(Ty)->getElementType();
  85
  86     // Size should be aligned to DWORD boundary
  87     Size += ((TD->getTypeAllocSize(Ty) + 3)/4)*4;
  88   }
  89
  90   // We're not supporting tooooo huge arguments :)
  91   Info.setBytesToPopOnReturn((unsigned int)Size);
  92   return Info;
  93 }
  94
  95 /// DecorateCygMingName - Query FunctionInfoMap and use this information for
  96 /// various name decorations for Cygwin and MingW.
  97 void X86ATTAsmPrinter::DecorateCygMingName(std::string &Name,
  98                                            const GlobalValue *GV) {
  99   assert(Subtarget->isTargetCygMing() && "This is only for cygwin and mingw");
 100
 101   const Function *F = dyn_cast<Function>(GV);
 102   if (!F) return;
 103
 104   // Save function name for later type emission.
 105   if (F->isDeclaration())
 106     CygMingStubs.insert(Name);
 107
 108   // We don't want to decorate non-stdcall or non-fastcall functions right now
 109   CallingConv::ID CC = F->getCallingConv();
 110   if (CC != CallingConv::X86_StdCall && CC != CallingConv::X86_FastCall)
 111     return;
 112
 113
 114   const X86MachineFunctionInfo *Info;
 115
 116   FMFInfoMap::const_iterator info_item = FunctionInfoMap.find(F);
 117   if (info_item == FunctionInfoMap.end()) {
 118     // Calculate apropriate function info and populate map
 119     FunctionInfoMap[F] = calculateFunctionInfo(F, TM.getTargetData());
 120     Info = &FunctionInfoMap[F];
 121   } else {
 122     Info = &info_item->second;
 123   }
 124
 125   const FunctionType *FT = F->getFunctionType();
 126   switch (Info->getDecorationStyle()) {
 127   case None:
 128     break;
 129   case StdCall:
 130     // "Pure" variadic functions do not receive @0 suffix.
 131     if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
 132         (FT->getNumParams() == 1 && F->hasStructRetAttr()))
 133       Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
 134     break;
 135   case FastCall:
 136     // "Pure" variadic functions do not receive @0 suffix.
 137     if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
 138         (FT->getNumParams() == 1 && F->hasStructRetAttr()))
 139       Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
 140
 141     if (Name[0] == '_') {
 142       Name[0] = '@';
 143     } else {
 144       Name = '@' + Name;
 145     }
 146     break;
 147   default:
 148     llvm_unreachable("Unsupported DecorationStyle");
 149   }
 150 }
 151
 152 void X86ATTAsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
 153   unsigned FnAlign = MF.getAlignment();
 154   const Function *F = MF.getFunction();
 155
 156   if (Subtarget->isTargetCygMing())
 157     DecorateCygMingName(CurrentFnName, F);
 158
 159   OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
 160   EmitAlignment(FnAlign, F);
 161
 162   switch (F->getLinkage()) {
 163   default: llvm_unreachable("Unknown linkage type!");
 164   case Function::InternalLinkage:  // Symbols default to internal.
 165   case Function::PrivateLinkage:
 166     break;
 167   case Function::DLLExportLinkage:
 168   case Function::ExternalLinkage:
 169     O << "\t.globl\t" << CurrentFnName << '\n';
 170     break;
 171   case Function::LinkerPrivateLinkage:
 172   case Function::LinkOnceAnyLinkage:
 173   case Function::LinkOnceODRLinkage:
 174   case Function::WeakAnyLinkage:
 175   case Function::WeakODRLinkage:
 176     if (Subtarget->isTargetDarwin()) {
 177       O << "\t.globl\t" << CurrentFnName << '\n';
 178       O << MAI->getWeakDefDirective() << CurrentFnName << '\n';
 179     } else if (Subtarget->isTargetCygMing()) {
 180       O << "\t.globl\t" << CurrentFnName << "\n"
 181            "\t.linkonce discard\n";
 182     } else {
 183       O << "\t.weak\t" << CurrentFnName << '\n';
 184     }
 185     break;
 186   }
 187
 188   printVisibility(CurrentFnName, F->getVisibility());
 189
 190   if (Subtarget->isTargetELF())
 191     O << "\t.type\t" << CurrentFnName << ",@function\n";
 192   else if (Subtarget->isTargetCygMing()) {
 193     O << "\t.def\t " << CurrentFnName
 194       << ";\t.scl\t" <<
 195       (F->hasInternalLinkage() ? COFF::C_STAT : COFF::C_EXT)
 196       << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
 197       << ";\t.endef\n";
 198   }
 199
 200   O << CurrentFnName << ':';
 201   if (VerboseAsm) {
 202     O.PadToColumn(MAI->getCommentColumn());
 203     O << MAI->getCommentString() << ' ';
 204     WriteAsOperand(O, F, /*PrintType=*/false, F->getParent());
 205   }
 206   O << '\n';
 207
 208   // Add some workaround for linkonce linkage on Cygwin\MinGW
 209   if (Subtarget->isTargetCygMing() &&
 210       (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
 211     O << "Lllvm$workaround$fake$stub$" << CurrentFnName << ":\n";
 212 }
 213
 214 /// runOnMachineFunction - This uses the printMachineInstruction()
 215 /// method to print assembly for each instruction.
 216 ///
 217 bool X86ATTAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
 218   const Function *F = MF.getFunction();
 219   this->MF = &MF;
 220   CallingConv::ID CC = F->getCallingConv();
 221
 222   SetupMachineFunction(MF);
 223   O << "\n\n";
 224
 225   // Populate function information map.  Actually, We don't want to populate
 226   // non-stdcall or non-fastcall functions' information right now.
 227   if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
 228     FunctionInfoMap[F] = *MF.getInfo<X86MachineFunctionInfo>();
 229
 230   // Print out constants referenced by the function
 231   EmitConstantPool(MF.getConstantPool());
 232
 233   if (F->hasDLLExportLinkage())
 234     DLLExportedFns.insert(Mang->getMangledName(F));
 235
 236   // Print the 'header' of function
 237   emitFunctionHeader(MF);
 238
 239   // Emit pre-function debug and/or EH information.
 240   if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
 241     DW->BeginFunction(&MF);
 242
 243   // Print out code for the function.
 244   bool hasAnyRealCode = false;
 245   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
 246        I != E; ++I) {
 247     // Print a label for the basic block.
 248     if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
 249       // This is an entry block or a block that's only reachable via a
 250       // fallthrough edge. In non-VerboseAsm mode, don't print the label.
 251     } else {
 252       printBasicBlockLabel(I, true, true, VerboseAsm);
 253       O << '\n';
 254     }
 255     for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
 256          II != IE; ++II) {
 257       // Print the assembly for the instruction.
 258       if (!II->isLabel())
 259         hasAnyRealCode = true;
 260       printMachineInstruction(II);
 261     }
 262   }
 263
 264   if (Subtarget->isTargetDarwin() && !hasAnyRealCode) {
 265     // If the function is empty, then we need to emit *something*. Otherwise,
 266     // the function's label might be associated with something that it wasn't
 267     // meant to be associated with. We emit a noop in this situation.
 268     // We are assuming inline asms are code.
 269     O << "\tnop\n";
 270   }
 271
 272   if (MAI->hasDotTypeDotSizeDirective())
 273     O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
 274
 275   // Emit post-function debug information.
 276   if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
 277     DW->EndFunction(&MF);
 278
 279   // Print out jump tables referenced by the function.
 280   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
 281
 282   // We didn't modify anything.
 283   return false;
 284 }
 285
 286 /// printSymbolOperand - Print a raw symbol reference operand.  This handles
 287 /// jump tables, constant pools, global address and external symbols, all of
 288 /// which print to a label with various suffixes for relocation types etc.
 289 void X86ATTAsmPrinter::printSymbolOperand(const MachineOperand &MO) {
 290   switch (MO.getType()) {
 291   default: llvm_unreachable("unknown symbol type!");
 292   case MachineOperand::MO_JumpTableIndex:
 293     O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << '_'
 294       << MO.getIndex();
 295     break;
 296   case MachineOperand::MO_ConstantPoolIndex:
 297     O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
 298       << MO.getIndex();
 299     printOffset(MO.getOffset());
 300     break;
 301   case MachineOperand::MO_GlobalAddress: {
 302     const GlobalValue *GV = MO.getGlobal();
 303
 304     const char *Suffix = "";
 305     if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
 306       Suffix = "$stub";
 307     else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
 308              MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
 309              MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
 310       Suffix = "$non_lazy_ptr";
 311
 312     std::string Name = Mang->getMangledName(GV, Suffix, Suffix[0] != '\0');
 313     if (Subtarget->isTargetCygMing())
 314       DecorateCygMingName(Name, GV);
 315
 316     // Handle dllimport linkage.
 317     if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
 318       Name = "__imp_" + Name;
 319
 320     if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
 321         MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE)
 322       GVStubs[Name] = Mang->getMangledName(GV);
 323     else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
 324       HiddenGVStubs[Name] = Mang->getMangledName(GV);
 325     else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
 326       FnStubs[Name] = Mang->getMangledName(GV);
 327
 328     // If the name begins with a dollar-sign, enclose it in parens.  We do this
 329     // to avoid having it look like an integer immediate to the assembler.
 330     if (Name[0] == '$')
 331       O << '(' << Name << ')';
 332     else
 333       O << Name;
 334
 335     printOffset(MO.getOffset());
 336     break;
 337   }
 338   case MachineOperand::MO_ExternalSymbol: {
 339     std::string Name = Mang->makeNameProper(MO.getSymbolName());
 340     if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
 341       FnStubs[Name+"$stub"] = Name;
 342       Name += "$stub";
 343     }
 344
 345     // If the name begins with a dollar-sign, enclose it in parens.  We do this
 346     // to avoid having it look like an integer immediate to the assembler.
 347     if (Name[0] == '$')
 348       O << '(' << Name << ')';
 349     else
 350       O << Name;
 351     break;
 352   }
 353   }
 354
 355   switch (MO.getTargetFlags()) {
 356   default:
 357     llvm_unreachable("Unknown target flag on GV operand");
 358   case X86II::MO_NO_FLAG:    // No flag.
 359     break;
 360   case X86II::MO_DARWIN_NONLAZY:
 361   case X86II::MO_DLLIMPORT:
 362   case X86II::MO_DARWIN_STUB:
 363     // These affect the name of the symbol, not any suffix.
 364     break;
 365   case X86II::MO_GOT_ABSOLUTE_ADDRESS:
 366     O << " + [.-";
 367     PrintPICBaseSymbol();
 368     O << ']';
 369     break;
 370   case X86II::MO_PIC_BASE_OFFSET:
 371   case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
 372   case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
 373     O << '-';
 374     PrintPICBaseSymbol();
 375     break;
 376   case X86II::MO_TLSGD:     O << "@TLSGD";     break;
 377   case X86II::MO_GOTTPOFF:  O << "@GOTTPOFF";  break;
 378   case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
 379   case X86II::MO_TPOFF:     O << "@TPOFF";     break;
 380   case X86II::MO_NTPOFF:    O << "@NTPOFF";    break;
 381   case X86II::MO_GOTPCREL:  O << "@GOTPCREL";  break;
 382   case X86II::MO_GOT:       O << "@GOT";       break;
 383   case X86II::MO_GOTOFF:    O << "@GOTOFF";    break;
 384   case X86II::MO_PLT:       O << "@PLT";       break;
 385   }
 386 }
 387
 388 /// print_pcrel_imm - This is used to print an immediate value that ends up
 389 /// being encoded as a pc-relative value.  These print slightly differently, for
 390 /// example, a $ is not emitted.
 391 void X86ATTAsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo) {
 392   const MachineOperand &MO = MI->getOperand(OpNo);
 393   switch (MO.getType()) {
 394   default: llvm_unreachable("Unknown pcrel immediate operand");
 395   case MachineOperand::MO_Immediate:
 396     O << MO.getImm();
 397     return;
 398   case MachineOperand::MO_MachineBasicBlock:
 399     printBasicBlockLabel(MO.getMBB(), false, false, false);
 400     return;
 401   case MachineOperand::MO_GlobalAddress:
 402   case MachineOperand::MO_ExternalSymbol:
 403     printSymbolOperand(MO);
 404     return;
 405   }
 406 }
 407
 408
 409
 410 void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
 411                                     const char *Modifier) {
 412   const MachineOperand &MO = MI->getOperand(OpNo);
 413   switch (MO.getType()) {
 414   default: llvm_unreachable("unknown operand type!");
 415   case MachineOperand::MO_Register: {
 416     assert(TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
 417            "Virtual registers should not make it this far!");
 418     O << '%';
 419     unsigned Reg = MO.getReg();
 420     if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
 421       EVT VT = (strcmp(Modifier+6,"64") == 0) ?
 422         MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
 423                     ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
 424       Reg = getX86SubSuperRegister(Reg, VT);
 425     }
 426     O << TRI->getAsmName(Reg);
 427     return;
 428   }
 429
 430   case MachineOperand::MO_Immediate:
 431     O << '$' << MO.getImm();
 432     return;
 433
 434   case MachineOperand::MO_JumpTableIndex:
 435   case MachineOperand::MO_ConstantPoolIndex:
 436   case MachineOperand::MO_GlobalAddress:
 437   case MachineOperand::MO_ExternalSymbol: {
 438     O << '$';
 439     printSymbolOperand(MO);
 440     break;
 441   }
 442   }
 443 }
 444
 445 void X86ATTAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
 446   unsigned char value = MI->getOperand(Op).getImm();
 447   assert(value <= 7 && "Invalid ssecc argument!");
 448   switch (value) {
 449   case 0: O << "eq"; break;
 450   case 1: O << "lt"; break;
 451   case 2: O << "le"; break;
 452   case 3: O << "unord"; break;
 453   case 4: O << "neq"; break;
 454   case 5: O << "nlt"; break;
 455   case 6: O << "nle"; break;
 456   case 7: O << "ord"; break;
 457   }
 458 }
 459
 460 void X86ATTAsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
 461                                             const char *Modifier) {
 462   const MachineOperand &BaseReg  = MI->getOperand(Op);
 463   const MachineOperand &IndexReg = MI->getOperand(Op+2);
 464   const MachineOperand &DispSpec = MI->getOperand(Op+3);
 465
 466   // If we really don't want to print out (rip), don't.
 467   bool HasBaseReg = BaseReg.getReg() != 0;
 468   if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
 469       BaseReg.getReg() == X86::RIP)
 470     HasBaseReg = false;
 471
 472   // HasParenPart - True if we will print out the () part of the mem ref.
 473   bool HasParenPart = IndexReg.getReg() || HasBaseReg;
 474
 475   if (DispSpec.isImm()) {
 476     int DispVal = DispSpec.getImm();
 477     if (DispVal || !HasParenPart)
 478       O << DispVal;
 479   } else {
 480     assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
 481            DispSpec.isJTI() || DispSpec.isSymbol());
 482     printSymbolOperand(MI->getOperand(Op+3));
 483   }
 484
 485   if (HasParenPart) {
 486     assert(IndexReg.getReg() != X86::ESP &&
 487            "X86 doesn't allow scaling by ESP");
 488
 489     O << '(';
 490     if (HasBaseReg)
 491       printOperand(MI, Op, Modifier);
 492
 493     if (IndexReg.getReg()) {
 494       O << ',';
 495       printOperand(MI, Op+2, Modifier);
 496       unsigned ScaleVal = MI->getOperand(Op+1).getImm();
 497       if (ScaleVal != 1)
 498         O << ',' << ScaleVal;
 499     }
 500     O << ')';
 501   }
 502 }
 503
 504 void X86ATTAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
 505                                          const char *Modifier) {
 506   assert(isMem(MI, Op) && "Invalid memory reference!");
 507   const MachineOperand &Segment = MI->getOperand(Op+4);
 508   if (Segment.getReg()) {
 509     printOperand(MI, Op+4, Modifier);
 510     O << ':';
 511   }
 512   printLeaMemReference(MI, Op, Modifier);
 513 }
 514
 515 void X86ATTAsmPrinter::printPICJumpTableSetLabel(unsigned uid,
 516                                            const MachineBasicBlock *MBB) const {
 517   if (!MAI->getSetDirective())
 518     return;
 519
 520   // We don't need .set machinery if we have GOT-style relocations
 521   if (Subtarget->isPICStyleGOT())
 522     return;
 523
 524   O << MAI->getSetDirective() << ' ' << MAI->getPrivateGlobalPrefix()
 525     << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
 526   printBasicBlockLabel(MBB, false, false, false);
 527   if (Subtarget->isPICStyleRIPRel())
 528     O << '-' << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
 529       << '_' << uid << '\n';
 530   else {
 531     O << '-';
 532     PrintPICBaseSymbol();
 533     O << '\n';
 534   }
 535 }
 536
 537
 538 void X86ATTAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
 539   PrintPICBaseSymbol();
 540   O << '\n';
 541   PrintPICBaseSymbol();
 542   O << ':';
 543 }
 544
 545
 546 void X86ATTAsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
 547                                               const MachineBasicBlock *MBB,
 548                                               unsigned uid) const {
 549   const char *JTEntryDirective = MJTI->getEntrySize() == 4 ?
 550     MAI->getData32bitsDirective() : MAI->getData64bitsDirective();
 551
 552   O << JTEntryDirective << ' ';
 553
 554   if (Subtarget->isPICStyleRIPRel() || Subtarget->isPICStyleStubPIC()) {
 555     O << MAI->getPrivateGlobalPrefix() << getFunctionNumber()
 556       << '_' << uid << "_set_" << MBB->getNumber();
 557   } else if (Subtarget->isPICStyleGOT()) {
 558     printBasicBlockLabel(MBB, false, false, false);
 559     O << "@GOTOFF";
 560   } else
 561     printBasicBlockLabel(MBB, false, false, false);
 562 }
 563
 564 bool X86ATTAsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode) {
 565   unsigned Reg = MO.getReg();
 566   switch (Mode) {
 567   default: return true;  // Unknown mode.
 568   case 'b': // Print QImode register
 569     Reg = getX86SubSuperRegister(Reg, MVT::i8);
 570     break;
 571   case 'h': // Print QImode high register
 572     Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
 573     break;
 574   case 'w': // Print HImode register
 575     Reg = getX86SubSuperRegister(Reg, MVT::i16);
 576     break;
 577   case 'k': // Print SImode register
 578     Reg = getX86SubSuperRegister(Reg, MVT::i32);
 579     break;
 580   case 'q': // Print DImode register
 581     Reg = getX86SubSuperRegister(Reg, MVT::i64);
 582     break;
 583   }
 584
 585   O << '%'<< TRI->getAsmName(Reg);
 586   return false;
 587 }
 588
 589 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 590 ///
 591 bool X86ATTAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 592                                        unsigned AsmVariant,
 593                                        const char *ExtraCode) {
 594   // Does this asm operand have a single letter operand modifier?
 595   if (ExtraCode && ExtraCode[0]) {
 596     if (ExtraCode[1] != 0) return true; // Unknown modifier.
 597
 598     const MachineOperand &MO = MI->getOperand(OpNo);
 599
 600     switch (ExtraCode[0]) {
 601     default: return true;  // Unknown modifier.
 602     case 'a': // This is an address.  Currently only 'i' and 'r' are expected.
 603       if (MO.isImm()) {
 604         O << MO.getImm();
 605         return false;
 606       }
 607       if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
 608         printSymbolOperand(MO);
 609         return false;
 610       }
 611       if (MO.isReg()) {
 612         O << '(';
 613         printOperand(MI, OpNo);
 614         O << ')';
 615         return false;
 616       }
 617       return true;
 618
 619     case 'c': // Don't print "$" before a global var name or constant.
 620       if (MO.isImm())
 621         O << MO.getImm();
 622       else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
 623         printSymbolOperand(MO);
 624       else
 625         printOperand(MI, OpNo);
 626       return false;
 627
 628     case 'A': // Print '*' before a register (it must be a register)
 629       if (MO.isReg()) {
 630         O << '*';
 631         printOperand(MI, OpNo);
 632         return false;
 633       }
 634       return true;
 635
 636     case 'b': // Print QImode register
 637     case 'h': // Print QImode high register
 638     case 'w': // Print HImode register
 639     case 'k': // Print SImode register
 640     case 'q': // Print DImode register
 641       if (MO.isReg())
 642         return printAsmMRegister(MO, ExtraCode[0]);
 643       printOperand(MI, OpNo);
 644       return false;
 645
 646     case 'P': // This is the operand of a call, treat specially.
 647       print_pcrel_imm(MI, OpNo);
 648       return false;
 649
 650     case 'n':  // Negate the immediate or print a '-' before the operand.
 651       // Note: this is a temporary solution. It should be handled target
 652       // independently as part of the 'MC' work.
 653       if (MO.isImm()) {
 654         O << -MO.getImm();
 655         return false;
 656       }
 657       O << '-';
 658     }
 659   }
 660
 661   printOperand(MI, OpNo);
 662   return false;
 663 }
 664
 665 bool X86ATTAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 666                                              unsigned OpNo,
 667                                              unsigned AsmVariant,
 668                                              const char *ExtraCode) {
 669   if (ExtraCode && ExtraCode[0]) {
 670     if (ExtraCode[1] != 0) return true; // Unknown modifier.
 671
 672     switch (ExtraCode[0]) {
 673     default: return true;  // Unknown modifier.
 674     case 'b': // Print QImode register
 675     case 'h': // Print QImode high register
 676     case 'w': // Print HImode register
 677     case 'k': // Print SImode register
 678     case 'q': // Print SImode register
 679       // These only apply to registers, ignore on mem.
 680       break;
 681     case 'P': // Don't print @PLT, but do print as memory.
 682       printMemReference(MI, OpNo, "no-rip");
 683       return false;
 684     }
 685   }
 686   printMemReference(MI, OpNo);
 687   return false;
 688 }
 689
 690
 691
 692 /// printMachineInstruction -- Print out a single X86 LLVM instruction MI in
 693 /// AT&T syntax to the current output stream.
 694 ///
 695 void X86ATTAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
 696   ++EmittedInsts;
 697
 698   // Call the autogenerated instruction printer routines.
 699   if (NewAsmPrinter)
 700     printInstructionThroughMCStreamer(MI);
 701   else
 702     printInstruction(MI);
 703 }
 704
 705 void X86ATTAsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
 706   const TargetData *TD = TM.getTargetData();
 707
 708   if (!GVar->hasInitializer())
 709     return;   // External global require no code
 710
 711   // Check to see if this is a special global used by LLVM, if so, emit it.
 712   if (EmitSpecialLLVMGlobal(GVar)) {
 713     if (Subtarget->isTargetDarwin() &&
 714         TM.getRelocationModel() == Reloc::Static) {
 715       if (GVar->getName() == "llvm.global_ctors")
 716         O << ".reference .constructors_used\n";
 717       else if (GVar->getName() == "llvm.global_dtors")
 718         O << ".reference .destructors_used\n";
 719     }
 720     return;
 721   }
 722
 723   std::string name = Mang->getMangledName(GVar);
 724   Constant *C = GVar->getInitializer();
 725   const Type *Type = C->getType();
 726   unsigned Size = TD->getTypeAllocSize(Type);
 727   unsigned Align = TD->getPreferredAlignmentLog(GVar);
 728
 729   printVisibility(name, GVar->getVisibility());
 730
 731   if (Subtarget->isTargetELF())
 732     O << "\t.type\t" << name << ",@object\n";
 733
 734
 735   SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GVar, TM);
 736   const MCSection *TheSection =
 737     getObjFileLowering().SectionForGlobal(GVar, GVKind, Mang, TM);
 738   OutStreamer.SwitchSection(TheSection);
 739
 740   // FIXME: get this stuff from section kind flags.
 741   if (C->isNullValue() && !GVar->hasSection() &&
 742       // Don't put things that should go in the cstring section into "comm".
 743       !TheSection->getKind().isMergeableCString()) {
 744     if (GVar->hasExternalLinkage()) {
 745       if (const char *Directive = MAI->getZeroFillDirective()) {
 746         O << "\t.globl " << name << '\n';
 747         O << Directive << "__DATA, __common, " << name << ", "
 748           << Size << ", " << Align << '\n';
 749         return;
 750       }
 751     }
 752
 753     if (!GVar->isThreadLocal() &&
 754         (GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
 755       if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
 756
 757       if (MAI->getLCOMMDirective() != NULL) {
 758         if (GVar->hasLocalLinkage()) {
 759           O << MAI->getLCOMMDirective() << name << ',' << Size;
 760           if (Subtarget->isTargetDarwin())
 761             O << ',' << Align;
 762         } else if (Subtarget->isTargetDarwin() && !GVar->hasCommonLinkage()) {
 763           O << "\t.globl " << name << '\n'
 764             << MAI->getWeakDefDirective() << name << '\n';
 765           EmitAlignment(Align, GVar);
 766           O << name << ":";
 767           if (VerboseAsm) {
 768             O.PadToColumn(MAI->getCommentColumn());
 769             O << MAI->getCommentString() << ' ';
 770             WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
 771           }
 772           O << '\n';
 773           EmitGlobalConstant(C);
 774           return;
 775         } else {
 776           O << MAI->getCOMMDirective()  << name << ',' << Size;
 777           if (MAI->getCOMMDirectiveTakesAlignment())
 778             O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
 779         }
 780       } else {
 781         if (!Subtarget->isTargetCygMing()) {
 782           if (GVar->hasLocalLinkage())
 783             O << "\t.local\t" << name << '\n';
 784         }
 785         O << MAI->getCOMMDirective()  << name << ',' << Size;
 786         if (MAI->getCOMMDirectiveTakesAlignment())
 787           O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
 788       }
 789       if (VerboseAsm) {
 790         O.PadToColumn(MAI->getCommentColumn());
 791         O << MAI->getCommentString() << ' ';
 792         WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
 793       }
 794       O << '\n';
 795       return;
 796     }
 797   }
 798
 799   switch (GVar->getLinkage()) {
 800   case GlobalValue::CommonLinkage:
 801   case GlobalValue::LinkOnceAnyLinkage:
 802   case GlobalValue::LinkOnceODRLinkage:
 803   case GlobalValue::WeakAnyLinkage:
 804   case GlobalValue::WeakODRLinkage:
 805   case GlobalValue::LinkerPrivateLinkage:
 806     if (Subtarget->isTargetDarwin()) {
 807       O << "\t.globl " << name << '\n'
 808         << MAI->getWeakDefDirective() << name << '\n';
 809     } else if (Subtarget->isTargetCygMing()) {
 810       O << "\t.globl\t" << name << "\n"
 811            "\t.linkonce same_size\n";
 812     } else {
 813       O << "\t.weak\t" << name << '\n';
 814     }
 815     break;
 816   case GlobalValue::DLLExportLinkage:
 817   case GlobalValue::AppendingLinkage:
 818     // FIXME: appending linkage variables should go into a section of
 819     // their name or something.  For now, just emit them as external.
 820   case GlobalValue::ExternalLinkage:
 821     // If external or appending, declare as a global symbol
 822     O << "\t.globl " << name << '\n';
 823     // FALL THROUGH
 824   case GlobalValue::PrivateLinkage:
 825   case GlobalValue::InternalLinkage:
 826      break;
 827   default:
 828     llvm_unreachable("Unknown linkage type!");
 829   }
 830
 831   EmitAlignment(Align, GVar);
 832   O << name << ":";
 833   if (VerboseAsm){
 834     O.PadToColumn(MAI->getCommentColumn());
 835     O << MAI->getCommentString() << ' ';
 836     WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
 837   }
 838   O << '\n';
 839
 840   EmitGlobalConstant(C);
 841
 842   if (MAI->hasDotTypeDotSizeDirective())
 843     O << "\t.size\t" << name << ", " << Size << '\n';
 844 }
 845
 846 bool X86ATTAsmPrinter::doFinalization(Module &M) {
 847   // Print out module-level global variables here.
 848   for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
 849        I != E; ++I) {
 850     if (I->hasDLLExportLinkage())
 851       DLLExportedGVs.insert(Mang->getMangledName(I));
 852   }
 853
 854   if (Subtarget->isTargetDarwin()) {
 855     // All darwin targets use mach-o.
 856     TargetLoweringObjectFileMachO &TLOFMacho =
 857       static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
 858
 859     // Add the (possibly multiple) personalities to the set of global value
 860     // stubs.  Only referenced functions get into the Personalities list.
 861     if (MAI->doesSupportExceptionHandling() && MMI && !Subtarget->is64Bit()) {
 862       const std::vector<Function*> &Personalities = MMI->getPersonalities();
 863       for (unsigned i = 0, e = Personalities.size(); i != e; ++i) {
 864         if (Personalities[i])
 865           GVStubs[Mang->getMangledName(Personalities[i], "$non_lazy_ptr",
 866                                        true /*private label*/)] =
 867             Mang->getMangledName(Personalities[i]);
 868       }
 869     }
 870
 871     // Output stubs for dynamically-linked functions
 872     if (!FnStubs.empty()) {
 873       const MCSection *TheSection =
 874         TLOFMacho.getMachOSection("__IMPORT", "__jump_table",
 875                                   MCSectionMachO::S_SYMBOL_STUBS |
 876                                   MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
 877                                   MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
 878                                   5, SectionKind::getMetadata());
 879       OutStreamer.SwitchSection(TheSection);
 880       for (StringMap<std::string>::iterator I = FnStubs.begin(),
 881            E = FnStubs.end(); I != E; ++I)
 882         O << I->getKeyData() << ":\n" << "\t.indirect_symbol " << I->second
 883           << "\n\thlt ; hlt ; hlt ; hlt ; hlt\n";
 884       O << '\n';
 885     }
 886
 887     // Output stubs for external and common global variables.
 888     if (!GVStubs.empty()) {
 889       const MCSection *TheSection =
 890         TLOFMacho.getMachOSection("__IMPORT", "__pointers",
 891                                   MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
 892                                   SectionKind::getMetadata());
 893       OutStreamer.SwitchSection(TheSection);
 894       for (StringMap<std::string>::iterator I = GVStubs.begin(),
 895            E = GVStubs.end(); I != E; ++I)
 896         O << I->getKeyData() << ":\n\t.indirect_symbol "
 897           << I->second << "\n\t.long\t0\n";
 898     }
 899
 900     if (!HiddenGVStubs.empty()) {
 901       OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
 902       EmitAlignment(2);
 903       for (StringMap<std::string>::iterator I = HiddenGVStubs.begin(),
 904            E = HiddenGVStubs.end(); I != E; ++I)
 905         O << I->getKeyData() << ":\n" << MAI->getData32bitsDirective()
 906           << I->second << '\n';
 907     }
 908
 909     // Funny Darwin hack: This flag tells the linker that no global symbols
 910     // contain code that falls through to other global symbols (e.g. the obvious
 911     // implementation of multiple entry points).  If this doesn't occur, the
 912     // linker can safely perform dead code stripping.  Since LLVM never
 913     // generates code that does this, it is always safe to set.
 914     O << "\t.subsections_via_symbols\n";
 915   } else if (Subtarget->isTargetCygMing()) {
 916     // Emit type information for external functions
 917     for (StringSet<>::iterator i = CygMingStubs.begin(), e = CygMingStubs.end();
 918          i != e; ++i) {
 919       O << "\t.def\t " << i->getKeyData()
 920         << ";\t.scl\t" << COFF::C_EXT
 921         << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
 922         << ";\t.endef\n";
 923     }
 924   }
 925
 926
 927   // Output linker support code for dllexported globals on windows.
 928   if (!DLLExportedGVs.empty() || !DLLExportedFns.empty()) {
 929     // dllexport symbols only exist on coff targets.
 930     TargetLoweringObjectFileCOFF &TLOFMacho =
 931       static_cast<TargetLoweringObjectFileCOFF&>(getObjFileLowering());
 932
 933     OutStreamer.SwitchSection(TLOFMacho.getCOFFSection(".section .drectve",true,
 934                                                  SectionKind::getMetadata()));
 935
 936     for (StringSet<>::iterator i = DLLExportedGVs.begin(),
 937          e = DLLExportedGVs.end(); i != e; ++i)
 938       O << "\t.ascii \" -export:" << i->getKeyData() << ",data\"\n";
 939
 940     for (StringSet<>::iterator i = DLLExportedFns.begin(),
 941          e = DLLExportedFns.end();
 942          i != e; ++i)
 943       O << "\t.ascii \" -export:" << i->getKeyData() << "\"\n";
 944   }
 945
 946   // Do common shutdown.
 947   return AsmPrinter::doFinalization(M);
 948 }
 949
 950 // Include the auto-generated portion of the assembly writer.
 951 #include "X86GenAsmWriter.inc"