PPCAsmPrinter.cpp revision 563321a2582851c653d0863e8e0bba3d483734f9 
1//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source 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 PowerPC assembly language. This printer is
12// the output mechanism used by `llc'.
13//
14// Documentation at http://developer.apple.com/documentation/DeveloperTools/
15// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
16//
17//===----------------------------------------------------------------------===//
18
19#define DEBUG_TYPE "asmprinter"
20#include "PPC.h"
21#include "PPCTargetMachine.h"
22#include "PPCSubtarget.h"
23#include "llvm/Constants.h"
24#include "llvm/DerivedTypes.h"
25#include "llvm/Module.h"
26#include "llvm/Assembly/Writer.h"
27#include "llvm/CodeGen/AsmPrinter.h"
28#include "llvm/CodeGen/DwarfWriter.h"
29#include "llvm/CodeGen/MachineDebugInfo.h"
30#include "llvm/CodeGen/MachineFunctionPass.h"
31#include "llvm/CodeGen/MachineInstr.h"
32#include "llvm/Support/Mangler.h"
33#include "llvm/Support/MathExtras.h"
34#include "llvm/Support/CommandLine.h"
35#include "llvm/Support/Debug.h"
36#include "llvm/Support/Compiler.h"
37#include "llvm/Target/TargetAsmInfo.h"
38#include "llvm/Target/MRegisterInfo.h"
39#include "llvm/Target/TargetInstrInfo.h"
40#include "llvm/Target/TargetOptions.h"
41#include "llvm/ADT/Statistic.h"
42#include "llvm/ADT/StringExtras.h"
43#include <iostream>
44#include <set>
45using namespace llvm;
46
47namespace {
48  Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
49
50  struct VISIBILITY_HIDDEN PPCAsmPrinter : public AsmPrinter {
51    std::set<std::string> FnStubs, GVStubs;
52
53    PPCAsmPrinter(std::ostream &O, TargetMachine &TM, TargetAsmInfo *T)
54      : AsmPrinter(O, TM, T) {}
55
56    virtual const char *getPassName() const {
57      return "PowerPC Assembly Printer";
58    }
59
60    PPCTargetMachine &getTM() {
61      return static_cast<PPCTargetMachine&>(TM);
62    }
63
64    unsigned enumRegToMachineReg(unsigned enumReg) {
65      switch (enumReg) {
66      default: assert(0 && "Unhandled register!"); break;
67      case PPC::CR0:  return  0;
68      case PPC::CR1:  return  1;
69      case PPC::CR2:  return  2;
70      case PPC::CR3:  return  3;
71      case PPC::CR4:  return  4;
72      case PPC::CR5:  return  5;
73      case PPC::CR6:  return  6;
74      case PPC::CR7:  return  7;
75      }
76      abort();
77    }
78
79    /// printInstruction - This method is automatically generated by tablegen
80    /// from the instruction set description.  This method returns true if the
81    /// machine instruction was sufficiently described to print it, otherwise it
82    /// returns false.
83    bool printInstruction(const MachineInstr *MI);
84
85    void printMachineInstruction(const MachineInstr *MI);
86    void printOp(const MachineOperand &MO);
87
88    void printOperand(const MachineInstr *MI, unsigned OpNo) {
89      const MachineOperand &MO = MI->getOperand(OpNo);
90      if (MO.isRegister()) {
91        assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
92        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
93      } else if (MO.isImmediate()) {
94        O << MO.getImmedValue();
95      } else {
96        printOp(MO);
97      }
98    }
99
100    bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
101                         unsigned AsmVariant, const char *ExtraCode);
102    bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
103                               unsigned AsmVariant, const char *ExtraCode);
104
105
106    void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
107      char value = MI->getOperand(OpNo).getImmedValue();
108      value = (value << (32-5)) >> (32-5);
109      O << (int)value;
110    }
111    void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
112      unsigned char value = MI->getOperand(OpNo).getImmedValue();
113      assert(value <= 31 && "Invalid u5imm argument!");
114      O << (unsigned int)value;
115    }
116    void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
117      unsigned char value = MI->getOperand(OpNo).getImmedValue();
118      assert(value <= 63 && "Invalid u6imm argument!");
119      O << (unsigned int)value;
120    }
121    void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
122      O << (short)MI->getOperand(OpNo).getImmedValue();
123    }
124    void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
125      O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
126    }
127    void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
128      O << (short)(MI->getOperand(OpNo).getImmedValue()*4);
129    }
130    void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
131      // Branches can take an immediate operand.  This is used by the branch
132      // selection pass to print $+8, an eight byte displacement from the PC.
133      if (MI->getOperand(OpNo).isImmediate()) {
134        O << "$+" << MI->getOperand(OpNo).getImmedValue()*4;
135      } else {
136        printOp(MI->getOperand(OpNo));
137      }
138    }
139    void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
140      const MachineOperand &MO = MI->getOperand(OpNo);
141      if (TM.getRelocationModel() != Reloc::Static) {
142        if (MO.getType() == MachineOperand::MO_GlobalAddress) {
143          GlobalValue *GV = MO.getGlobal();
144          if (((GV->isExternal() || GV->hasWeakLinkage() ||
145                GV->hasLinkOnceLinkage()))) {
146            // Dynamically-resolved functions need a stub for the function.
147            std::string Name = Mang->getValueName(GV);
148            FnStubs.insert(Name);
149            O << "L" << Name << "$stub";
150            return;
151          }
152        }
153        if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
154          std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
155          FnStubs.insert(Name);
156          O << "L" << Name << "$stub";
157          return;
158        }
159      }
160
161      printOp(MI->getOperand(OpNo));
162    }
163    void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
164     O << (int)MI->getOperand(OpNo).getImmedValue()*4;
165    }
166    void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
167      O << "\"L" << getFunctionNumber() << "$pb\"\n";
168      O << "\"L" << getFunctionNumber() << "$pb\":";
169    }
170    void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
171      if (MI->getOperand(OpNo).isImmediate()) {
172        printS16ImmOperand(MI, OpNo);
173      } else {
174        O << "ha16(";
175        printOp(MI->getOperand(OpNo));
176        if (TM.getRelocationModel() == Reloc::PIC_)
177          O << "-\"L" << getFunctionNumber() << "$pb\")";
178        else
179          O << ')';
180      }
181    }
182    void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
183      if (MI->getOperand(OpNo).isImmediate()) {
184        printS16ImmOperand(MI, OpNo);
185      } else {
186        O << "lo16(";
187        printOp(MI->getOperand(OpNo));
188        if (TM.getRelocationModel() == Reloc::PIC_)
189          O << "-\"L" << getFunctionNumber() << "$pb\")";
190        else
191          O << ')';
192      }
193    }
194    void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
195      unsigned CCReg = MI->getOperand(OpNo).getReg();
196      unsigned RegNo = enumRegToMachineReg(CCReg);
197      O << (0x80 >> RegNo);
198    }
199    // The new addressing mode printers.
200    void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
201      printSymbolLo(MI, OpNo);
202      O << '(';
203      if (MI->getOperand(OpNo+1).isRegister() &&
204          MI->getOperand(OpNo+1).getReg() == PPC::R0)
205        O << "0";
206      else
207        printOperand(MI, OpNo+1);
208      O << ')';
209    }
210    void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) {
211      if (MI->getOperand(OpNo).isImmediate())
212        printS16X4ImmOperand(MI, OpNo);
213      else
214        printSymbolLo(MI, OpNo);
215      O << '(';
216      if (MI->getOperand(OpNo+1).isRegister() &&
217          MI->getOperand(OpNo+1).getReg() == PPC::R0)
218        O << "0";
219      else
220        printOperand(MI, OpNo+1);
221      O << ')';
222    }
223
224    void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
225      // When used as the base register, r0 reads constant zero rather than
226      // the value contained in the register.  For this reason, the darwin
227      // assembler requires that we print r0 as 0 (no r) when used as the base.
228      const MachineOperand &MO = MI->getOperand(OpNo);
229      if (MO.getReg() == PPC::R0)
230        O << '0';
231      else
232        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
233      O << ", ";
234      printOperand(MI, OpNo+1);
235    }
236
237    virtual bool runOnMachineFunction(MachineFunction &F) = 0;
238    virtual bool doFinalization(Module &M) = 0;
239
240  };
241
242  struct VISIBILITY_HIDDEN DarwinTargetAsmInfo : public TargetAsmInfo {
243    DarwinTargetAsmInfo(PPCTargetMachine &TM) {
244      bool isPPC64 = TM.getSubtargetImpl()->isPPC64();
245
246      CommentString = ";";
247      GlobalPrefix = "_";
248      PrivateGlobalPrefix = "L";
249      ZeroDirective = "\t.space\t";
250      SetDirective = "\t.set";
251      Data64bitsDirective = isPPC64 ? ".quad\t" : 0;
252      AlignmentIsInBytes = false;
253      ConstantPoolSection = "\t.const\t";
254      JumpTableDataSection = ".const";
255      JumpTableTextSection = "\t.text";
256      LCOMMDirective = "\t.lcomm\t";
257      StaticCtorsSection = ".mod_init_func";
258      StaticDtorsSection = ".mod_term_func";
259      InlineAsmStart = "# InlineAsm Start";
260      InlineAsmEnd = "# InlineAsm End";
261
262      NeedsSet = true;
263      AddressSize = isPPC64 ? 8 : 4;
264      DwarfAbbrevSection = ".section __DWARF,__debug_abbrev";
265      DwarfInfoSection = ".section __DWARF,__debug_info";
266      DwarfLineSection = ".section __DWARF,__debug_line";
267      DwarfFrameSection = ".section __DWARF,__debug_frame";
268      DwarfPubNamesSection = ".section __DWARF,__debug_pubnames";
269      DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes";
270      DwarfStrSection = ".section __DWARF,__debug_str";
271      DwarfLocSection = ".section __DWARF,__debug_loc";
272      DwarfARangesSection = ".section __DWARF,__debug_aranges";
273      DwarfRangesSection = ".section __DWARF,__debug_ranges";
274      DwarfMacInfoSection = ".section __DWARF,__debug_macinfo";
275    }
276  };
277
278  /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
279  /// X
280  struct VISIBILITY_HIDDEN DarwinAsmPrinter : public PPCAsmPrinter {
281
282    DwarfWriter DW;
283
284    DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM, TargetAsmInfo *T)
285      : PPCAsmPrinter(O, TM, T), DW(O, this, T) {
286      bool isPPC64 = TM.getSubtargetImpl()->isPPC64();
287    }
288
289    virtual const char *getPassName() const {
290      return "Darwin PPC Assembly Printer";
291    }
292
293    bool runOnMachineFunction(MachineFunction &F);
294    bool doInitialization(Module &M);
295    bool doFinalization(Module &M);
296
297    void getAnalysisUsage(AnalysisUsage &AU) const {
298      AU.setPreservesAll();
299      AU.addRequired<MachineDebugInfo>();
300      PPCAsmPrinter::getAnalysisUsage(AU);
301    }
302
303  };
304} // end of anonymous namespace
305
306/// createDarwinCodePrinterPass - Returns a pass that prints the PPC assembly
307/// code for a MachineFunction to the given output stream, in a format that the
308/// Darwin assembler can deal with.
309///
310FunctionPass *llvm::createDarwinCodePrinterPass(std::ostream &o,
311                                                PPCTargetMachine &tm) {
312  TargetAsmInfo *TAI = new DarwinTargetAsmInfo(tm);
313  return new DarwinAsmPrinter(o, tm, TAI);
314}
315
316// Include the auto-generated portion of the assembly writer
317#include "PPCGenAsmWriter.inc"
318
319void PPCAsmPrinter::printOp(const MachineOperand &MO) {
320  switch (MO.getType()) {
321  case MachineOperand::MO_Immediate:
322    std::cerr << "printOp() does not handle immediate values\n";
323    abort();
324    return;
325
326  case MachineOperand::MO_MachineBasicBlock:
327    printBasicBlockLabel(MO.getMachineBasicBlock());
328    return;
329  case MachineOperand::MO_JumpTableIndex:
330    O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
331      << '_' << MO.getJumpTableIndex();
332    // FIXME: PIC relocation model
333    return;
334  case MachineOperand::MO_ConstantPoolIndex:
335    O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
336      << '_' << MO.getConstantPoolIndex();
337    return;
338  case MachineOperand::MO_ExternalSymbol:
339    // Computing the address of an external symbol, not calling it.
340    if (TM.getRelocationModel() != Reloc::Static) {
341      std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
342      GVStubs.insert(Name);
343      O << "L" << Name << "$non_lazy_ptr";
344      return;
345    }
346    O << TAI->getGlobalPrefix() << MO.getSymbolName();
347    return;
348  case MachineOperand::MO_GlobalAddress: {
349    // Computing the address of a global symbol, not calling it.
350    GlobalValue *GV = MO.getGlobal();
351    std::string Name = Mang->getValueName(GV);
352    int offset = MO.getOffset();
353
354    // External or weakly linked global variables need non-lazily-resolved stubs
355    if (TM.getRelocationModel() != Reloc::Static) {
356      if (((GV->isExternal() || GV->hasWeakLinkage() ||
357            GV->hasLinkOnceLinkage()))) {
358        GVStubs.insert(Name);
359        O << "L" << Name << "$non_lazy_ptr";
360        return;
361      }
362    }
363
364    O << Name;
365    return;
366  }
367
368  default:
369    O << "<unknown operand type: " << MO.getType() << ">";
370    return;
371  }
372}
373
374/// PrintAsmOperand - Print out an operand for an inline asm expression.
375///
376bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
377                                    unsigned AsmVariant,
378                                    const char *ExtraCode) {
379  // Does this asm operand have a single letter operand modifier?
380  if (ExtraCode && ExtraCode[0]) {
381    if (ExtraCode[1] != 0) return true; // Unknown modifier.
382
383    switch (ExtraCode[0]) {
384    default: return true;  // Unknown modifier.
385    case 'L': // Write second word of DImode reference.
386      // Verify that this operand has two consecutive registers.
387      if (!MI->getOperand(OpNo).isRegister() ||
388          OpNo+1 == MI->getNumOperands() ||
389          !MI->getOperand(OpNo+1).isRegister())
390        return true;
391      ++OpNo;   // Return the high-part.
392      break;
393    }
394  }
395
396  printOperand(MI, OpNo);
397  return false;
398}
399
400bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
401                                          unsigned AsmVariant,
402                                          const char *ExtraCode) {
403  if (ExtraCode && ExtraCode[0])
404    return true; // Unknown modifier.
405  printMemRegReg(MI, OpNo);
406  return false;
407}
408
409/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
410/// the current output stream.
411///
412void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
413  ++EmittedInsts;
414
415  // Check for slwi/srwi mnemonics.
416  if (MI->getOpcode() == PPC::RLWINM) {
417    bool FoundMnemonic = false;
418    unsigned char SH = MI->getOperand(2).getImmedValue();
419    unsigned char MB = MI->getOperand(3).getImmedValue();
420    unsigned char ME = MI->getOperand(4).getImmedValue();
421    if (SH <= 31 && MB == 0 && ME == (31-SH)) {
422      O << "slwi "; FoundMnemonic = true;
423    }
424    if (SH <= 31 && MB == (32-SH) && ME == 31) {
425      O << "srwi "; FoundMnemonic = true;
426      SH = 32-SH;
427    }
428    if (FoundMnemonic) {
429      printOperand(MI, 0);
430      O << ", ";
431      printOperand(MI, 1);
432      O << ", " << (unsigned int)SH << "\n";
433      return;
434    }
435  } else if (MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) {
436    if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
437      O << "mr ";
438      printOperand(MI, 0);
439      O << ", ";
440      printOperand(MI, 1);
441      O << "\n";
442      return;
443    }
444  }
445
446  if (printInstruction(MI))
447    return; // Printer was automatically generated
448
449  assert(0 && "Unhandled instruction in asm writer!");
450  abort();
451  return;
452}
453
454/// runOnMachineFunction - This uses the printMachineInstruction()
455/// method to print assembly for each instruction.
456///
457bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
458  DW.SetDebugInfo(&getAnalysis<MachineDebugInfo>());
459
460  SetupMachineFunction(MF);
461  O << "\n\n";
462
463  // Print out constants referenced by the function
464  EmitConstantPool(MF.getConstantPool());
465
466  // Print out jump tables referenced by the function
467  EmitJumpTableInfo(MF.getJumpTableInfo());
468
469  // Print out labels for the function.
470  const Function *F = MF.getFunction();
471  switch (F->getLinkage()) {
472  default: assert(0 && "Unknown linkage type!");
473  case Function::InternalLinkage:  // Symbols default to internal.
474    SwitchToTextSection("\t.text", F);
475    break;
476  case Function::ExternalLinkage:
477    SwitchToTextSection("\t.text", F);
478    O << "\t.globl\t" << CurrentFnName << "\n";
479    break;
480  case Function::WeakLinkage:
481  case Function::LinkOnceLinkage:
482    SwitchToTextSection(
483                ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", F);
484    O << "\t.globl\t" << CurrentFnName << "\n";
485    O << "\t.weak_definition\t" << CurrentFnName << "\n";
486    break;
487  }
488  EmitAlignment(4, F);
489  O << CurrentFnName << ":\n";
490
491  // Emit pre-function debug information.
492  DW.BeginFunction(&MF);
493
494  // Print out code for the function.
495  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
496       I != E; ++I) {
497    // Print a label for the basic block.
498    if (I != MF.begin()) {
499      printBasicBlockLabel(I, true);
500      O << '\n';
501    }
502    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
503         II != E; ++II) {
504      // Print the assembly for the instruction.
505      O << "\t";
506      printMachineInstruction(II);
507    }
508  }
509
510  // Emit post-function debug information.
511  DW.EndFunction();
512
513  // We didn't modify anything.
514  return false;
515}
516
517
518bool DarwinAsmPrinter::doInitialization(Module &M) {
519  if (TM.getSubtarget<PPCSubtarget>().isGigaProcessor())
520    O << "\t.machine ppc970\n";
521  AsmPrinter::doInitialization(M);
522
523  // Darwin wants symbols to be quoted if they have complex names.
524  Mang->setUseQuotes(true);
525
526  // Emit initial debug information.
527  DW.BeginModule(&M);
528  return false;
529}
530
531bool DarwinAsmPrinter::doFinalization(Module &M) {
532  const TargetData *TD = TM.getTargetData();
533
534  // Print out module-level global variables here.
535  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
536       I != E; ++I) {
537    if (!I->hasInitializer()) continue;   // External global require no code
538
539    // Check to see if this is a special global used by LLVM, if so, emit it.
540    if (EmitSpecialLLVMGlobal(I))
541      continue;
542
543    std::string name = Mang->getValueName(I);
544    Constant *C = I->getInitializer();
545    unsigned Size = TD->getTypeSize(C->getType());
546    unsigned Align = getPreferredAlignmentLog(I);
547
548    if (C->isNullValue() && /* FIXME: Verify correct */
549        (I->hasInternalLinkage() || I->hasWeakLinkage() ||
550         I->hasLinkOnceLinkage() ||
551         (I->hasExternalLinkage() && !I->hasSection()))) {
552      if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
553      if (I->hasExternalLinkage()) {
554        O << "\t.globl " << name << '\n';
555        O << "\t.zerofill __DATA, __common, " << name << ", "
556          << Size << ", " << Align;
557      } else if (I->hasInternalLinkage()) {
558        SwitchToDataSection("\t.data", I);
559        O << TAI->getLCOMMDirective() << name << "," << Size << "," << Align;
560      } else {
561        SwitchToDataSection("\t.data", I);
562        O << ".comm " << name << "," << Size;
563      }
564      O << "\t\t; '" << I->getName() << "'\n";
565    } else {
566      switch (I->getLinkage()) {
567      case GlobalValue::LinkOnceLinkage:
568      case GlobalValue::WeakLinkage:
569        O << "\t.globl " << name << '\n'
570          << "\t.weak_definition " << name << '\n';
571        SwitchToDataSection(".section __DATA,__datacoal_nt,coalesced", I);
572        break;
573      case GlobalValue::AppendingLinkage:
574        // FIXME: appending linkage variables should go into a section of
575        // their name or something.  For now, just emit them as external.
576      case GlobalValue::ExternalLinkage:
577        // If external or appending, declare as a global symbol
578        O << "\t.globl " << name << "\n";
579        // FALL THROUGH
580      case GlobalValue::InternalLinkage:
581        SwitchToDataSection("\t.data", I);
582        break;
583      default:
584        std::cerr << "Unknown linkage type!";
585        abort();
586      }
587
588      EmitAlignment(Align, I);
589      O << name << ":\t\t\t\t; '" << I->getName() << "'\n";
590      EmitGlobalConstant(C);
591      O << '\n';
592    }
593  }
594
595  bool isPPC64 = TD->getPointerSizeInBits() == 64;
596
597  // Output stubs for dynamically-linked functions
598  if (TM.getRelocationModel() == Reloc::PIC_) {
599    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
600         i != e; ++i) {
601      SwitchToTextSection(".section __TEXT,__picsymbolstub1,symbol_stubs,"
602                          "pure_instructions,32", 0);
603      EmitAlignment(4);
604      O << "L" << *i << "$stub:\n";
605      O << "\t.indirect_symbol " << *i << "\n";
606      O << "\tmflr r0\n";
607      O << "\tbcl 20,31,L0$" << *i << "\n";
608      O << "L0$" << *i << ":\n";
609      O << "\tmflr r11\n";
610      O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
611      O << "\tmtlr r0\n";
612      if (isPPC64)
613        O << "\tldu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
614      else
615        O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
616      O << "\tmtctr r12\n";
617      O << "\tbctr\n";
618      SwitchToDataSection(".lazy_symbol_pointer", 0);
619      O << "L" << *i << "$lazy_ptr:\n";
620      O << "\t.indirect_symbol " << *i << "\n";
621      if (isPPC64)
622        O << "\t.quad dyld_stub_binding_helper\n";
623      else
624        O << "\t.long dyld_stub_binding_helper\n";
625    }
626  } else {
627    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
628         i != e; ++i) {
629      SwitchToTextSection(".section __TEXT,__symbol_stub1,symbol_stubs,"
630                          "pure_instructions,16", 0);
631      EmitAlignment(4);
632      O << "L" << *i << "$stub:\n";
633      O << "\t.indirect_symbol " << *i << "\n";
634      O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
635      if (isPPC64)
636        O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
637      else
638        O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
639      O << "\tmtctr r12\n";
640      O << "\tbctr\n";
641      SwitchToDataSection(".lazy_symbol_pointer", 0);
642      O << "L" << *i << "$lazy_ptr:\n";
643      O << "\t.indirect_symbol " << *i << "\n";
644      if (isPPC64)
645        O << "\t.quad dyld_stub_binding_helper\n";
646      else
647        O << "\t.long dyld_stub_binding_helper\n";
648    }
649  }
650
651  O << "\n";
652
653  // Output stubs for external and common global variables.
654  if (GVStubs.begin() != GVStubs.end()) {
655    SwitchToDataSection(".non_lazy_symbol_pointer", 0);
656    for (std::set<std::string>::iterator I = GVStubs.begin(),
657         E = GVStubs.end(); I != E; ++I) {
658      O << "L" << *I << "$non_lazy_ptr:\n";
659      O << "\t.indirect_symbol " << *I << "\n";
660      if (isPPC64)
661        O << "\t.quad\t0\n";
662      else
663        O << "\t.long\t0\n";
664
665    }
666  }
667
668  // Emit initial debug information.
669  DW.EndModule();
670
671  // Funny Darwin hack: This flag tells the linker that no global symbols
672  // contain code that falls through to other global symbols (e.g. the obvious
673  // implementation of multiple entry points).  If this doesn't occur, the
674  // linker can safely perform dead code stripping.  Since LLVM never generates
675  // code that does this, it is always safe to set.
676  O << "\t.subsections_via_symbols\n";
677
678  AsmPrinter::doFinalization(M);
679  return false; // success
680}
681
682