PPCAsmPrinter.cpp revision 2ead458ae8423d6ecaec7cbd45e1e2c71ce9e618
1//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC 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 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 "PPCPredicates.h"
22#include "PPCTargetMachine.h"
23#include "PPCSubtarget.h"
24#include "llvm/Analysis/DebugInfo.h"
25#include "llvm/Constants.h"
26#include "llvm/DerivedTypes.h"
27#include "llvm/Module.h"
28#include "llvm/Assembly/Writer.h"
29#include "llvm/CodeGen/AsmPrinter.h"
30#include "llvm/CodeGen/MachineFunctionPass.h"
31#include "llvm/CodeGen/MachineInstr.h"
32#include "llvm/CodeGen/MachineInstrBuilder.h"
33#include "llvm/CodeGen/MachineModuleInfoImpls.h"
34#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
35#include "llvm/MC/MCAsmInfo.h"
36#include "llvm/MC/MCContext.h"
37#include "llvm/MC/MCExpr.h"
38#include "llvm/MC/MCInst.h"
39#include "llvm/MC/MCSectionMachO.h"
40#include "llvm/MC/MCStreamer.h"
41#include "llvm/MC/MCSymbol.h"
42#include "llvm/Target/Mangler.h"
43#include "llvm/Target/TargetRegisterInfo.h"
44#include "llvm/Target/TargetInstrInfo.h"
45#include "llvm/Target/TargetOptions.h"
46#include "llvm/Target/TargetRegistry.h"
47#include "llvm/Support/CommandLine.h"
48#include "llvm/Support/Debug.h"
49#include "llvm/Support/MathExtras.h"
50#include "llvm/Support/ErrorHandling.h"
51#include "llvm/Support/raw_ostream.h"
52#include "llvm/ADT/StringExtras.h"
53#include "llvm/ADT/StringSet.h"
54#include "llvm/ADT/SmallString.h"
55#include "InstPrinter/PPCInstPrinter.h"
56using namespace llvm;
57
58// This option tells the asmprinter to use the new (experimental) MCInstPrinter
59// path.
60static cl::opt<bool> UseInstPrinter("enable-ppc-inst-printer",
61                                    cl::ReallyHidden
62                                    //, cl::init(true)
63                                    );
64
65namespace {
66  class PPCAsmPrinter : public AsmPrinter {
67  protected:
68    DenseMap<MCSymbol*, MCSymbol*> TOC;
69    const PPCSubtarget &Subtarget;
70    uint64_t LabelID;
71  public:
72    explicit PPCAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
73      : AsmPrinter(TM, Streamer),
74        Subtarget(TM.getSubtarget<PPCSubtarget>()), LabelID(0) {}
75
76    virtual const char *getPassName() const {
77      return "PowerPC Assembly Printer";
78    }
79
80    unsigned enumRegToMachineReg(unsigned enumReg) {
81      switch (enumReg) {
82      default: llvm_unreachable("Unhandled register!");
83      case PPC::CR0:  return  0;
84      case PPC::CR1:  return  1;
85      case PPC::CR2:  return  2;
86      case PPC::CR3:  return  3;
87      case PPC::CR4:  return  4;
88      case PPC::CR5:  return  5;
89      case PPC::CR6:  return  6;
90      case PPC::CR7:  return  7;
91      }
92      llvm_unreachable(0);
93    }
94
95    /// printInstruction - This method is automatically generated by tablegen
96    /// from the instruction set description.  This method returns true if the
97    /// machine instruction was sufficiently described to print it, otherwise it
98    /// returns false.
99    void printInstruction(const MachineInstr *MI, raw_ostream &O);
100    static const char *getRegisterName(unsigned RegNo);
101
102
103    virtual void EmitInstruction(const MachineInstr *MI);
104    void printOp(const MachineOperand &MO, raw_ostream &O);
105
106    /// stripRegisterPrefix - This method strips the character prefix from a
107    /// register name so that only the number is left.  Used by for linux asm.
108    const char *stripRegisterPrefix(const char *RegName) {
109      switch (RegName[0]) {
110      case 'r':
111      case 'f':
112      case 'v': return RegName + 1;
113      case 'c': if (RegName[1] == 'r') return RegName + 2;
114      }
115
116      return RegName;
117    }
118
119    /// printRegister - Print register according to target requirements.
120    ///
121    void printRegister(const MachineOperand &MO, bool R0AsZero, raw_ostream &O){
122      unsigned RegNo = MO.getReg();
123      assert(TargetRegisterInfo::isPhysicalRegister(RegNo) && "Not physreg??");
124
125      // If we should use 0 for R0.
126      if (R0AsZero && RegNo == PPC::R0) {
127        O << "0";
128        return;
129      }
130
131      const char *RegName = getRegisterName(RegNo);
132      // Linux assembler (Others?) does not take register mnemonics.
133      // FIXME - What about special registers used in mfspr/mtspr?
134      if (!Subtarget.isDarwin()) RegName = stripRegisterPrefix(RegName);
135      O << RegName;
136    }
137
138    void printOperand(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
139      const MachineOperand &MO = MI->getOperand(OpNo);
140      if (MO.isReg()) {
141        printRegister(MO, false, O);
142      } else if (MO.isImm()) {
143        O << MO.getImm();
144      } else {
145        printOp(MO, O);
146      }
147    }
148
149    bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
150                         unsigned AsmVariant, const char *ExtraCode,
151                         raw_ostream &O);
152    bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
153                               unsigned AsmVariant, const char *ExtraCode,
154                               raw_ostream &O);
155
156
157    void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo,
158                           raw_ostream &O) {
159      char value = MI->getOperand(OpNo).getImm();
160      value = (value << (32-5)) >> (32-5);
161      O << (int)value;
162    }
163    void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo,
164                           raw_ostream &O) {
165      unsigned char value = MI->getOperand(OpNo).getImm();
166      assert(value <= 31 && "Invalid u5imm argument!");
167      O << (unsigned int)value;
168    }
169    void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo,
170                           raw_ostream &O) {
171      unsigned char value = MI->getOperand(OpNo).getImm();
172      assert(value <= 63 && "Invalid u6imm argument!");
173      O << (unsigned int)value;
174    }
175    void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo,
176                            raw_ostream &O) {
177      O << (short)MI->getOperand(OpNo).getImm();
178    }
179    void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo,
180                            raw_ostream &O) {
181      O << (unsigned short)MI->getOperand(OpNo).getImm();
182    }
183    void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo,
184                              raw_ostream &O) {
185      if (MI->getOperand(OpNo).isImm()) {
186        O << (short)(MI->getOperand(OpNo).getImm()*4);
187      } else {
188        O << "lo16(";
189        printOp(MI->getOperand(OpNo), O);
190        if (TM.getRelocationModel() == Reloc::PIC_)
191          O << "-\"L" << getFunctionNumber() << "$pb\")";
192        else
193          O << ')';
194      }
195    }
196    void printBranchOperand(const MachineInstr *MI, unsigned OpNo,
197                            raw_ostream &O) {
198      // Branches can take an immediate operand.  This is used by the branch
199      // selection pass to print $+8, an eight byte displacement from the PC.
200      if (MI->getOperand(OpNo).isImm()) {
201        O << "$+" << MI->getOperand(OpNo).getImm()*4;
202      } else {
203        printOp(MI->getOperand(OpNo), O);
204      }
205    }
206    void printCallOperand(const MachineInstr *MI, unsigned OpNo,
207                          raw_ostream &O) {
208      const MachineOperand &MO = MI->getOperand(OpNo);
209      if (TM.getRelocationModel() != Reloc::Static) {
210        if (MO.isGlobal()) {
211          const GlobalValue *GV = MO.getGlobal();
212          if (GV->isDeclaration() || GV->isWeakForLinker()) {
213            // Dynamically-resolved functions need a stub for the function.
214            MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
215            MachineModuleInfoImpl::StubValueTy &StubSym =
216              MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
217            if (StubSym.getPointer() == 0)
218              StubSym = MachineModuleInfoImpl::
219                StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
220            O << *Sym;
221            return;
222          }
223        }
224        if (MO.isSymbol()) {
225          SmallString<128> TempNameStr;
226          TempNameStr += StringRef(MO.getSymbolName());
227          TempNameStr += StringRef("$stub");
228
229          MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
230          MachineModuleInfoImpl::StubValueTy &StubSym =
231            MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
232          if (StubSym.getPointer() == 0)
233            StubSym = MachineModuleInfoImpl::
234              StubValueTy(GetExternalSymbolSymbol(MO.getSymbolName()), true);
235          O << *Sym;
236          return;
237        }
238      }
239
240      printOp(MI->getOperand(OpNo), O);
241    }
242    void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo,
243                             raw_ostream &O) {
244     O << (int)MI->getOperand(OpNo).getImm()*4;
245    }
246    void printPICLabel(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
247      O << "\"L" << getFunctionNumber() << "$pb\"\n";
248      O << "\"L" << getFunctionNumber() << "$pb\":";
249    }
250    void printSymbolHi(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
251      if (MI->getOperand(OpNo).isImm()) {
252        printS16ImmOperand(MI, OpNo, O);
253      } else {
254        if (Subtarget.isDarwin()) O << "ha16(";
255        printOp(MI->getOperand(OpNo), O);
256        if (TM.getRelocationModel() == Reloc::PIC_)
257          O << "-\"L" << getFunctionNumber() << "$pb\"";
258        if (Subtarget.isDarwin())
259          O << ')';
260        else
261          O << "@ha";
262      }
263    }
264    void printSymbolLo(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
265      if (MI->getOperand(OpNo).isImm()) {
266        printS16ImmOperand(MI, OpNo, O);
267      } else {
268        if (Subtarget.isDarwin()) O << "lo16(";
269        printOp(MI->getOperand(OpNo), O);
270        if (TM.getRelocationModel() == Reloc::PIC_)
271          O << "-\"L" << getFunctionNumber() << "$pb\"";
272        if (Subtarget.isDarwin())
273          O << ')';
274        else
275          O << "@l";
276      }
277    }
278    void printcrbitm(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
279      unsigned CCReg = MI->getOperand(OpNo).getReg();
280      unsigned RegNo = enumRegToMachineReg(CCReg);
281      O << (0x80 >> RegNo);
282    }
283    // The new addressing mode printers.
284    void printMemRegImm(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
285      printSymbolLo(MI, OpNo, O);
286      O << '(';
287      if (MI->getOperand(OpNo+1).isReg() &&
288          MI->getOperand(OpNo+1).getReg() == PPC::R0)
289        O << "0";
290      else
291        printOperand(MI, OpNo+1, O);
292      O << ')';
293    }
294    void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo,
295                               raw_ostream &O) {
296      if (MI->getOperand(OpNo).isImm())
297        printS16X4ImmOperand(MI, OpNo, O);
298      else
299        printSymbolLo(MI, OpNo, O);
300      O << '(';
301      if (MI->getOperand(OpNo+1).isReg() &&
302          MI->getOperand(OpNo+1).getReg() == PPC::R0)
303        O << "0";
304      else
305        printOperand(MI, OpNo+1, O);
306      O << ')';
307    }
308
309    void printMemRegReg(const MachineInstr *MI, unsigned OpNo, raw_ostream &O) {
310      // When used as the base register, r0 reads constant zero rather than
311      // the value contained in the register.  For this reason, the darwin
312      // assembler requires that we print r0 as 0 (no r) when used as the base.
313      const MachineOperand &MO = MI->getOperand(OpNo);
314      printRegister(MO, true, O);
315      O << ", ";
316      printOperand(MI, OpNo+1, O);
317    }
318
319    void printTOCEntryLabel(const MachineInstr *MI, unsigned OpNo,
320                            raw_ostream &O) {
321      const MachineOperand &MO = MI->getOperand(OpNo);
322      assert(MO.isGlobal());
323      MCSymbol *Sym = Mang->getSymbol(MO.getGlobal());
324
325      // Map symbol -> label of TOC entry.
326      MCSymbol *&TOCEntry = TOC[Sym];
327      if (TOCEntry == 0)
328        TOCEntry = OutContext.
329          GetOrCreateSymbol(StringRef(MAI->getPrivateGlobalPrefix()) +
330                            "C" + Twine(LabelID++));
331
332      O << *TOCEntry << "@toc";
333    }
334
335    void printPredicateOperand(const MachineInstr *MI, unsigned OpNo,
336                               raw_ostream &O, const char *Modifier);
337
338    MachineLocation getDebugValueLocation(const MachineInstr *MI) const {
339
340      MachineLocation Location;
341      assert (MI->getNumOperands() == 4 && "Invalid no. of machine operands!");
342      // Frame address.  Currently handles register +- offset only.
343      if (MI->getOperand(0).isReg() && MI->getOperand(2).isImm())
344        Location.set(MI->getOperand(0).getReg(), MI->getOperand(2).getImm());
345      else {
346        DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
347      }
348      return Location;
349    }
350  };
351
352  /// PPCLinuxAsmPrinter - PowerPC assembly printer, customized for Linux
353  class PPCLinuxAsmPrinter : public PPCAsmPrinter {
354  public:
355    explicit PPCLinuxAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
356      : PPCAsmPrinter(TM, Streamer) {}
357
358    virtual const char *getPassName() const {
359      return "Linux PPC Assembly Printer";
360    }
361
362    bool doFinalization(Module &M);
363
364    virtual void EmitFunctionEntryLabel();
365  };
366
367  /// PPCDarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac
368  /// OS X
369  class PPCDarwinAsmPrinter : public PPCAsmPrinter {
370  public:
371    explicit PPCDarwinAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
372      : PPCAsmPrinter(TM, Streamer) {}
373
374    virtual const char *getPassName() const {
375      return "Darwin PPC Assembly Printer";
376    }
377
378    bool doFinalization(Module &M);
379    void EmitStartOfAsmFile(Module &M);
380
381    void EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs);
382  };
383} // end of anonymous namespace
384
385// Include the auto-generated portion of the assembly writer
386#include "PPCGenAsmWriter.inc"
387
388void PPCAsmPrinter::printOp(const MachineOperand &MO, raw_ostream &O) {
389  switch (MO.getType()) {
390  case MachineOperand::MO_Immediate:
391    llvm_unreachable("printOp() does not handle immediate values");
392
393  case MachineOperand::MO_MachineBasicBlock:
394    O << *MO.getMBB()->getSymbol();
395    return;
396  case MachineOperand::MO_JumpTableIndex:
397    O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
398      << '_' << MO.getIndex();
399    // FIXME: PIC relocation model
400    return;
401  case MachineOperand::MO_ConstantPoolIndex:
402    O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
403      << '_' << MO.getIndex();
404    return;
405  case MachineOperand::MO_BlockAddress:
406    O << *GetBlockAddressSymbol(MO.getBlockAddress());
407    return;
408  case MachineOperand::MO_ExternalSymbol: {
409    // Computing the address of an external symbol, not calling it.
410    if (TM.getRelocationModel() == Reloc::Static) {
411      O << *GetExternalSymbolSymbol(MO.getSymbolName());
412      return;
413    }
414
415    MCSymbol *NLPSym =
416      OutContext.GetOrCreateSymbol(StringRef(MAI->getGlobalPrefix())+
417                                   MO.getSymbolName()+"$non_lazy_ptr");
418    MachineModuleInfoImpl::StubValueTy &StubSym =
419      MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(NLPSym);
420    if (StubSym.getPointer() == 0)
421      StubSym = MachineModuleInfoImpl::
422        StubValueTy(GetExternalSymbolSymbol(MO.getSymbolName()), true);
423
424    O << *NLPSym;
425    return;
426  }
427  case MachineOperand::MO_GlobalAddress: {
428    // Computing the address of a global symbol, not calling it.
429    const GlobalValue *GV = MO.getGlobal();
430    MCSymbol *SymToPrint;
431
432    // External or weakly linked global variables need non-lazily-resolved stubs
433    if (TM.getRelocationModel() != Reloc::Static &&
434        (GV->isDeclaration() || GV->isWeakForLinker())) {
435      if (!GV->hasHiddenVisibility()) {
436        SymToPrint = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
437        MachineModuleInfoImpl::StubValueTy &StubSym =
438          MMI->getObjFileInfo<MachineModuleInfoMachO>()
439            .getGVStubEntry(SymToPrint);
440        if (StubSym.getPointer() == 0)
441          StubSym = MachineModuleInfoImpl::
442            StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
443      } else if (GV->isDeclaration() || GV->hasCommonLinkage() ||
444                 GV->hasAvailableExternallyLinkage()) {
445        SymToPrint = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
446
447        MachineModuleInfoImpl::StubValueTy &StubSym =
448          MMI->getObjFileInfo<MachineModuleInfoMachO>().
449                    getHiddenGVStubEntry(SymToPrint);
450        if (StubSym.getPointer() == 0)
451          StubSym = MachineModuleInfoImpl::
452            StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
453      } else {
454        SymToPrint = Mang->getSymbol(GV);
455      }
456    } else {
457      SymToPrint = Mang->getSymbol(GV);
458    }
459
460    O << *SymToPrint;
461
462    printOffset(MO.getOffset(), O);
463    return;
464  }
465
466  default:
467    O << "<unknown operand type: " << MO.getType() << ">";
468    return;
469  }
470}
471
472/// PrintAsmOperand - Print out an operand for an inline asm expression.
473///
474bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
475                                    unsigned AsmVariant,
476                                    const char *ExtraCode, raw_ostream &O) {
477  // Does this asm operand have a single letter operand modifier?
478  if (ExtraCode && ExtraCode[0]) {
479    if (ExtraCode[1] != 0) return true; // Unknown modifier.
480
481    switch (ExtraCode[0]) {
482    default: return true;  // Unknown modifier.
483    case 'c': // Don't print "$" before a global var name or constant.
484      // PPC never has a prefix.
485      printOperand(MI, OpNo, O);
486      return false;
487    case 'L': // Write second word of DImode reference.
488      // Verify that this operand has two consecutive registers.
489      if (!MI->getOperand(OpNo).isReg() ||
490          OpNo+1 == MI->getNumOperands() ||
491          !MI->getOperand(OpNo+1).isReg())
492        return true;
493      ++OpNo;   // Return the high-part.
494      break;
495    case 'I':
496      // Write 'i' if an integer constant, otherwise nothing.  Used to print
497      // addi vs add, etc.
498      if (MI->getOperand(OpNo).isImm())
499        O << "i";
500      return false;
501    }
502  }
503
504  printOperand(MI, OpNo, O);
505  return false;
506}
507
508// At the moment, all inline asm memory operands are a single register.
509// In any case, the output of this routine should always be just one
510// assembler operand.
511
512bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
513                                          unsigned AsmVariant,
514                                          const char *ExtraCode,
515                                          raw_ostream &O) {
516  if (ExtraCode && ExtraCode[0])
517    return true; // Unknown modifier.
518  assert (MI->getOperand(OpNo).isReg());
519  O << "0(";
520  printOperand(MI, OpNo, O);
521  O << ")";
522  return false;
523}
524
525void PPCAsmPrinter::printPredicateOperand(const MachineInstr *MI, unsigned OpNo,
526                                          raw_ostream &O, const char *Modifier){
527  assert(Modifier && "Must specify 'cc' or 'reg' as predicate op modifier!");
528  unsigned Code = MI->getOperand(OpNo).getImm();
529  if (!strcmp(Modifier, "cc")) {
530    switch ((PPC::Predicate)Code) {
531    case PPC::PRED_ALWAYS: return; // Don't print anything for always.
532    case PPC::PRED_LT: O << "lt"; return;
533    case PPC::PRED_LE: O << "le"; return;
534    case PPC::PRED_EQ: O << "eq"; return;
535    case PPC::PRED_GE: O << "ge"; return;
536    case PPC::PRED_GT: O << "gt"; return;
537    case PPC::PRED_NE: O << "ne"; return;
538    case PPC::PRED_UN: O << "un"; return;
539    case PPC::PRED_NU: O << "nu"; return;
540    }
541
542  } else {
543    assert(!strcmp(Modifier, "reg") &&
544           "Need to specify 'cc' or 'reg' as predicate op modifier!");
545    // Don't print the register for 'always'.
546    if (Code == PPC::PRED_ALWAYS) return;
547    printOperand(MI, OpNo+1, O);
548  }
549}
550
551
552/// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
553/// the current output stream.
554///
555void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
556  if (UseInstPrinter) {
557    MCInst TmpInst;
558
559    // Lower multi-instruction pseudo operations.
560    switch (MI->getOpcode()) {
561    default: break;
562
563    case PPC::MFCRpseud:
564      // Transform: %R3 = MFCRpseud %CR7
565      // Into:      %R3 = MFCR      ;; cr7
566      OutStreamer.AddComment(getRegisterName(MI->getOperand(1).getReg()));
567      TmpInst.setOpcode(PPC::MFCR);
568      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
569      OutStreamer.EmitInstruction(TmpInst);
570      return;
571    }
572
573    LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
574    OutStreamer.EmitInstruction(TmpInst);
575    return;
576  }
577
578
579  SmallString<128> Str;
580  raw_svector_ostream O(Str);
581
582  if (MI->getOpcode() == TargetOpcode::DBG_VALUE) {
583    unsigned NOps = MI->getNumOperands();
584    assert(NOps==4);
585    O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
586    // cast away const; DIetc do not take const operands for some reason.
587    DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
588    O << V.getName();
589    O << " <- ";
590    // Frame address.  Currently handles register +- offset only.
591    assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm());
592    O << '['; printOperand(MI, 0, O); O << '+'; printOperand(MI, 1, O);
593    O << ']';
594    O << "+";
595    printOperand(MI, NOps-2, O);
596    OutStreamer.EmitRawText(O.str());
597    return;
598  }
599  // Check for slwi/srwi mnemonics.
600  if (MI->getOpcode() == PPC::RLWINM) {
601    unsigned char SH = MI->getOperand(2).getImm();
602    unsigned char MB = MI->getOperand(3).getImm();
603    unsigned char ME = MI->getOperand(4).getImm();
604    bool useSubstituteMnemonic = false;
605    if (SH <= 31 && MB == 0 && ME == (31-SH)) {
606      O << "\tslwi "; useSubstituteMnemonic = true;
607    }
608    if (SH <= 31 && MB == (32-SH) && ME == 31) {
609      O << "\tsrwi "; useSubstituteMnemonic = true;
610      SH = 32-SH;
611    }
612    if (useSubstituteMnemonic) {
613      printOperand(MI, 0, O);
614      O << ", ";
615      printOperand(MI, 1, O);
616      O << ", " << (unsigned int)SH;
617      OutStreamer.EmitRawText(O.str());
618      return;
619    }
620  }
621
622  if ((MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) &&
623      MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
624    O << "\tmr ";
625    printOperand(MI, 0, O);
626    O << ", ";
627    printOperand(MI, 1, O);
628    OutStreamer.EmitRawText(O.str());
629    return;
630  }
631
632  if (MI->getOpcode() == PPC::RLDICR) {
633    unsigned char SH = MI->getOperand(2).getImm();
634    unsigned char ME = MI->getOperand(3).getImm();
635    // rldicr RA, RS, SH, 63-SH == sldi RA, RS, SH
636    if (63-SH == ME) {
637      O << "\tsldi ";
638      printOperand(MI, 0, O);
639      O << ", ";
640      printOperand(MI, 1, O);
641      O << ", " << (unsigned int)SH;
642      OutStreamer.EmitRawText(O.str());
643      return;
644    }
645  }
646
647  printInstruction(MI, O);
648  OutStreamer.EmitRawText(O.str());
649}
650
651void PPCLinuxAsmPrinter::EmitFunctionEntryLabel() {
652  if (!Subtarget.isPPC64())  // linux/ppc32 - Normal entry label.
653    return AsmPrinter::EmitFunctionEntryLabel();
654
655  // Emit an official procedure descriptor.
656  // FIXME 64-bit SVR4: Use MCSection here!
657  OutStreamer.EmitRawText(StringRef("\t.section\t\".opd\",\"aw\""));
658  OutStreamer.EmitRawText(StringRef("\t.align 3"));
659  OutStreamer.EmitLabel(CurrentFnSym);
660  OutStreamer.EmitRawText("\t.quad .L." + Twine(CurrentFnSym->getName()) +
661                          ",.TOC.@tocbase");
662  OutStreamer.EmitRawText(StringRef("\t.previous"));
663  OutStreamer.EmitRawText(".L." + Twine(CurrentFnSym->getName()) + ":");
664}
665
666
667bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
668  const TargetData *TD = TM.getTargetData();
669
670  bool isPPC64 = TD->getPointerSizeInBits() == 64;
671
672  if (isPPC64 && !TOC.empty()) {
673    // FIXME 64-bit SVR4: Use MCSection here?
674    OutStreamer.EmitRawText(StringRef("\t.section\t\".toc\",\"aw\""));
675
676    // FIXME: This is nondeterminstic!
677    for (DenseMap<MCSymbol*, MCSymbol*>::iterator I = TOC.begin(),
678         E = TOC.end(); I != E; ++I) {
679      OutStreamer.EmitLabel(I->second);
680      OutStreamer.EmitRawText("\t.tc " + Twine(I->first->getName()) +
681                              "[TC]," + I->first->getName());
682    }
683  }
684
685  return AsmPrinter::doFinalization(M);
686}
687
688void PPCDarwinAsmPrinter::EmitStartOfAsmFile(Module &M) {
689  static const char *const CPUDirectives[] = {
690    "",
691    "ppc",
692    "ppc601",
693    "ppc602",
694    "ppc603",
695    "ppc7400",
696    "ppc750",
697    "ppc970",
698    "ppc64"
699  };
700
701  unsigned Directive = Subtarget.getDarwinDirective();
702  if (Subtarget.isGigaProcessor() && Directive < PPC::DIR_970)
703    Directive = PPC::DIR_970;
704  if (Subtarget.hasAltivec() && Directive < PPC::DIR_7400)
705    Directive = PPC::DIR_7400;
706  if (Subtarget.isPPC64() && Directive < PPC::DIR_970)
707    Directive = PPC::DIR_64;
708  assert(Directive <= PPC::DIR_64 && "Directive out of range.");
709  OutStreamer.EmitRawText("\t.machine " + Twine(CPUDirectives[Directive]));
710
711  // Prime text sections so they are adjacent.  This reduces the likelihood a
712  // large data or debug section causes a branch to exceed 16M limit.
713  const TargetLoweringObjectFileMachO &TLOFMacho =
714    static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
715  OutStreamer.SwitchSection(TLOFMacho.getTextCoalSection());
716  if (TM.getRelocationModel() == Reloc::PIC_) {
717    OutStreamer.SwitchSection(
718           OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
719                                      MCSectionMachO::S_SYMBOL_STUBS |
720                                      MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
721                                      32, SectionKind::getText()));
722  } else if (TM.getRelocationModel() == Reloc::DynamicNoPIC) {
723    OutStreamer.SwitchSection(
724           OutContext.getMachOSection("__TEXT","__symbol_stub1",
725                                      MCSectionMachO::S_SYMBOL_STUBS |
726                                      MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
727                                      16, SectionKind::getText()));
728  }
729  OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
730}
731
732static MCSymbol *GetLazyPtr(MCSymbol *Sym, MCContext &Ctx) {
733  // Remove $stub suffix, add $lazy_ptr.
734  SmallString<128> TmpStr(Sym->getName().begin(), Sym->getName().end()-5);
735  TmpStr += "$lazy_ptr";
736  return Ctx.GetOrCreateSymbol(TmpStr.str());
737}
738
739static MCSymbol *GetAnonSym(MCSymbol *Sym, MCContext &Ctx) {
740  // Add $tmp suffix to $stub, yielding $stub$tmp.
741  SmallString<128> TmpStr(Sym->getName().begin(), Sym->getName().end());
742  TmpStr += "$tmp";
743  return Ctx.GetOrCreateSymbol(TmpStr.str());
744}
745
746void PPCDarwinAsmPrinter::
747EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs) {
748  bool isPPC64 = TM.getTargetData()->getPointerSizeInBits() == 64;
749
750  const TargetLoweringObjectFileMachO &TLOFMacho =
751    static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
752
753  // .lazy_symbol_pointer
754  const MCSection *LSPSection = TLOFMacho.getLazySymbolPointerSection();
755
756  // Output stubs for dynamically-linked functions
757  if (TM.getRelocationModel() == Reloc::PIC_) {
758    const MCSection *StubSection =
759    OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
760                               MCSectionMachO::S_SYMBOL_STUBS |
761                               MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
762                               32, SectionKind::getText());
763    for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
764      OutStreamer.SwitchSection(StubSection);
765      EmitAlignment(4);
766
767      MCSymbol *Stub = Stubs[i].first;
768      MCSymbol *RawSym = Stubs[i].second.getPointer();
769      MCSymbol *LazyPtr = GetLazyPtr(Stub, OutContext);
770      MCSymbol *AnonSymbol = GetAnonSym(Stub, OutContext);
771
772      OutStreamer.EmitLabel(Stub);
773      OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
774      // FIXME: MCize this.
775      OutStreamer.EmitRawText(StringRef("\tmflr r0"));
776      OutStreamer.EmitRawText("\tbcl 20,31," + Twine(AnonSymbol->getName()));
777      OutStreamer.EmitLabel(AnonSymbol);
778      OutStreamer.EmitRawText(StringRef("\tmflr r11"));
779      OutStreamer.EmitRawText("\taddis r11,r11,ha16("+Twine(LazyPtr->getName())+
780                              "-" + AnonSymbol->getName() + ")");
781      OutStreamer.EmitRawText(StringRef("\tmtlr r0"));
782
783      if (isPPC64)
784        OutStreamer.EmitRawText("\tldu r12,lo16(" + Twine(LazyPtr->getName()) +
785                                "-" + AnonSymbol->getName() + ")(r11)");
786      else
787        OutStreamer.EmitRawText("\tlwzu r12,lo16(" + Twine(LazyPtr->getName()) +
788                                "-" + AnonSymbol->getName() + ")(r11)");
789      OutStreamer.EmitRawText(StringRef("\tmtctr r12"));
790      OutStreamer.EmitRawText(StringRef("\tbctr"));
791
792      OutStreamer.SwitchSection(LSPSection);
793      OutStreamer.EmitLabel(LazyPtr);
794      OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
795
796      if (isPPC64)
797        OutStreamer.EmitRawText(StringRef("\t.quad dyld_stub_binding_helper"));
798      else
799        OutStreamer.EmitRawText(StringRef("\t.long dyld_stub_binding_helper"));
800    }
801    OutStreamer.AddBlankLine();
802    return;
803  }
804
805  const MCSection *StubSection =
806    OutContext.getMachOSection("__TEXT","__symbol_stub1",
807                               MCSectionMachO::S_SYMBOL_STUBS |
808                               MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
809                               16, SectionKind::getText());
810  for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
811    MCSymbol *Stub = Stubs[i].first;
812    MCSymbol *RawSym = Stubs[i].second.getPointer();
813    MCSymbol *LazyPtr = GetLazyPtr(Stub, OutContext);
814
815    OutStreamer.SwitchSection(StubSection);
816    EmitAlignment(4);
817    OutStreamer.EmitLabel(Stub);
818    OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
819    OutStreamer.EmitRawText("\tlis r11,ha16(" + Twine(LazyPtr->getName()) +")");
820    if (isPPC64)
821      OutStreamer.EmitRawText("\tldu r12,lo16(" + Twine(LazyPtr->getName()) +
822                              ")(r11)");
823    else
824      OutStreamer.EmitRawText("\tlwzu r12,lo16(" + Twine(LazyPtr->getName()) +
825                              ")(r11)");
826    OutStreamer.EmitRawText(StringRef("\tmtctr r12"));
827    OutStreamer.EmitRawText(StringRef("\tbctr"));
828    OutStreamer.SwitchSection(LSPSection);
829    OutStreamer.EmitLabel(LazyPtr);
830    OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
831
832    if (isPPC64)
833      OutStreamer.EmitRawText(StringRef("\t.quad dyld_stub_binding_helper"));
834    else
835      OutStreamer.EmitRawText(StringRef("\t.long dyld_stub_binding_helper"));
836  }
837
838  OutStreamer.AddBlankLine();
839}
840
841
842bool PPCDarwinAsmPrinter::doFinalization(Module &M) {
843  bool isPPC64 = TM.getTargetData()->getPointerSizeInBits() == 64;
844
845  // Darwin/PPC always uses mach-o.
846  const TargetLoweringObjectFileMachO &TLOFMacho =
847    static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
848  MachineModuleInfoMachO &MMIMacho =
849    MMI->getObjFileInfo<MachineModuleInfoMachO>();
850
851  MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetFnStubList();
852  if (!Stubs.empty())
853    EmitFunctionStubs(Stubs);
854
855  if (MAI->doesSupportExceptionHandling() && MMI) {
856    // Add the (possibly multiple) personalities to the set of global values.
857    // Only referenced functions get into the Personalities list.
858    const std::vector<const Function*> &Personalities = MMI->getPersonalities();
859    for (std::vector<const Function*>::const_iterator I = Personalities.begin(),
860         E = Personalities.end(); I != E; ++I) {
861      if (*I) {
862        MCSymbol *NLPSym = GetSymbolWithGlobalValueBase(*I, "$non_lazy_ptr");
863        MachineModuleInfoImpl::StubValueTy &StubSym =
864          MMIMacho.getGVStubEntry(NLPSym);
865        StubSym = MachineModuleInfoImpl::StubValueTy(Mang->getSymbol(*I), true);
866      }
867    }
868  }
869
870  // Output stubs for dynamically-linked functions.
871  Stubs = MMIMacho.GetGVStubList();
872
873  // Output macho stubs for external and common global variables.
874  if (!Stubs.empty()) {
875    // Switch with ".non_lazy_symbol_pointer" directive.
876    OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection());
877    EmitAlignment(isPPC64 ? 3 : 2);
878
879    for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
880      // L_foo$stub:
881      OutStreamer.EmitLabel(Stubs[i].first);
882      //   .indirect_symbol _foo
883      MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
884      OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol);
885
886      if (MCSym.getInt())
887        // External to current translation unit.
888        OutStreamer.EmitIntValue(0, isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
889      else
890        // Internal to current translation unit.
891        //
892        // When we place the LSDA into the TEXT section, the type info pointers
893        // need to be indirect and pc-rel. We accomplish this by using NLPs.
894        // However, sometimes the types are local to the file. So we need to
895        // fill in the value for the NLP in those cases.
896        OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
897                                                      OutContext),
898                              isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
899    }
900
901    Stubs.clear();
902    OutStreamer.AddBlankLine();
903  }
904
905  Stubs = MMIMacho.GetHiddenGVStubList();
906  if (!Stubs.empty()) {
907    OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
908    EmitAlignment(isPPC64 ? 3 : 2);
909
910    for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
911      // L_foo$stub:
912      OutStreamer.EmitLabel(Stubs[i].first);
913      //   .long _foo
914      OutStreamer.EmitValue(MCSymbolRefExpr::
915                            Create(Stubs[i].second.getPointer(),
916                                   OutContext),
917                            isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
918    }
919
920    Stubs.clear();
921    OutStreamer.AddBlankLine();
922  }
923
924  // Funny Darwin hack: This flag tells the linker that no global symbols
925  // contain code that falls through to other global symbols (e.g. the obvious
926  // implementation of multiple entry points).  If this doesn't occur, the
927  // linker can safely perform dead code stripping.  Since LLVM never generates
928  // code that does this, it is always safe to set.
929  OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
930
931  return AsmPrinter::doFinalization(M);
932}
933
934/// createPPCAsmPrinterPass - Returns a pass that prints the PPC assembly code
935/// for a MachineFunction to the given output stream, in a format that the
936/// Darwin assembler can deal with.
937///
938static AsmPrinter *createPPCAsmPrinterPass(TargetMachine &tm,
939                                           MCStreamer &Streamer) {
940  const PPCSubtarget *Subtarget = &tm.getSubtarget<PPCSubtarget>();
941
942  if (Subtarget->isDarwin())
943    return new PPCDarwinAsmPrinter(tm, Streamer);
944  return new PPCLinuxAsmPrinter(tm, Streamer);
945}
946
947static MCInstPrinter *createPPCMCInstPrinter(const Target &T,
948                                             unsigned SyntaxVariant,
949                                             const MCAsmInfo &MAI) {
950  return new PPCInstPrinter(MAI, SyntaxVariant);
951}
952
953
954// Force static initialization.
955extern "C" void LLVMInitializePowerPCAsmPrinter() {
956  TargetRegistry::RegisterAsmPrinter(ThePPC32Target, createPPCAsmPrinterPass);
957  TargetRegistry::RegisterAsmPrinter(ThePPC64Target, createPPCAsmPrinterPass);
958
959  TargetRegistry::RegisterMCInstPrinter(ThePPC32Target, createPPCMCInstPrinter);
960  TargetRegistry::RegisterMCInstPrinter(ThePPC64Target, createPPCMCInstPrinter);
961}
962