PPCAsmPrinter.cpp revision 7e097e463314baa3c964a977408aa51ecabe7796 
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/Target/MRegisterInfo.h"
37#include "llvm/Target/TargetInstrInfo.h"
38#include "llvm/Target/TargetOptions.h"
39#include "llvm/ADT/Statistic.h"
40#include "llvm/ADT/StringExtras.h"
41#include <iostream>
42#include <set>
43using namespace llvm;
44
45namespace {
46  Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
47
48  class PPCAsmPrinter : public AsmPrinter {
49  public:
50    std::set<std::string> FnStubs, GVStubs;
51
52    PPCAsmPrinter(std::ostream &O, TargetMachine &TM)
53      : AsmPrinter(O, TM) {}
54
55    virtual const char *getPassName() const {
56      return "PowerPC Assembly Printer";
57    }
58
59    PPCTargetMachine &getTM() {
60      return static_cast<PPCTargetMachine&>(TM);
61    }
62
63    unsigned enumRegToMachineReg(unsigned enumReg) {
64      switch (enumReg) {
65      default: assert(0 && "Unhandled register!"); break;
66      case PPC::CR0:  return  0;
67      case PPC::CR1:  return  1;
68      case PPC::CR2:  return  2;
69      case PPC::CR3:  return  3;
70      case PPC::CR4:  return  4;
71      case PPC::CR5:  return  5;
72      case PPC::CR6:  return  6;
73      case PPC::CR7:  return  7;
74      }
75      abort();
76    }
77
78    /// printInstruction - This method is automatically generated by tablegen
79    /// from the instruction set description.  This method returns true if the
80    /// machine instruction was sufficiently described to print it, otherwise it
81    /// returns false.
82    bool printInstruction(const MachineInstr *MI);
83
84    void printMachineInstruction(const MachineInstr *MI);
85    void printOp(const MachineOperand &MO);
86
87    void printOperand(const MachineInstr *MI, unsigned OpNo) {
88      const MachineOperand &MO = MI->getOperand(OpNo);
89      if (MO.isRegister()) {
90        assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
91        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
92      } else if (MO.isImmediate()) {
93        O << MO.getImmedValue();
94      } else {
95        printOp(MO);
96      }
97    }
98
99    bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
100                         unsigned AsmVariant, const char *ExtraCode);
101    bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
102                               unsigned AsmVariant, const char *ExtraCode);
103
104
105    void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
106      char value = MI->getOperand(OpNo).getImmedValue();
107      value = (value << (32-5)) >> (32-5);
108      O << (int)value;
109    }
110    void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
111      unsigned char value = MI->getOperand(OpNo).getImmedValue();
112      assert(value <= 31 && "Invalid u5imm argument!");
113      O << (unsigned int)value;
114    }
115    void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
116      unsigned char value = MI->getOperand(OpNo).getImmedValue();
117      assert(value <= 63 && "Invalid u6imm argument!");
118      O << (unsigned int)value;
119    }
120    void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
121      O << (short)MI->getOperand(OpNo).getImmedValue();
122    }
123    void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
124      O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
125    }
126    void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
127      O << (short)MI->getOperand(OpNo).getImmedValue()*4;
128    }
129    void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
130      // Branches can take an immediate operand.  This is used by the branch
131      // selection pass to print $+8, an eight byte displacement from the PC.
132      if (MI->getOperand(OpNo).isImmediate()) {
133        O << "$+" << MI->getOperand(OpNo).getImmedValue();
134      } else {
135        printOp(MI->getOperand(OpNo));
136      }
137    }
138    void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
139      const MachineOperand &MO = MI->getOperand(OpNo);
140      if (TM.getRelocationModel() != Reloc::Static) {
141        if (MO.getType() == MachineOperand::MO_GlobalAddress) {
142          GlobalValue *GV = MO.getGlobal();
143          if (((GV->isExternal() || GV->hasWeakLinkage() ||
144                GV->hasLinkOnceLinkage()))) {
145            // Dynamically-resolved functions need a stub for the function.
146            std::string Name = Mang->getValueName(GV);
147            FnStubs.insert(Name);
148            O << "L" << Name << "$stub";
149            return;
150          }
151        }
152        if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
153          std::string Name(GlobalPrefix); Name += MO.getSymbolName();
154          FnStubs.insert(Name);
155          O << "L" << Name << "$stub";
156          return;
157        }
158      }
159
160      printOp(MI->getOperand(OpNo));
161    }
162    void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
163     O << (int)MI->getOperand(OpNo).getImmedValue()*4;
164    }
165    void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
166      O << "\"L" << getFunctionNumber() << "$pb\"\n";
167      O << "\"L" << getFunctionNumber() << "$pb\":";
168    }
169    void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
170      if (MI->getOperand(OpNo).isImmediate()) {
171        printS16ImmOperand(MI, OpNo);
172      } else {
173        O << "ha16(";
174        printOp(MI->getOperand(OpNo));
175        if (TM.getRelocationModel() == Reloc::PIC)
176          O << "-\"L" << getFunctionNumber() << "$pb\")";
177        else
178          O << ')';
179      }
180    }
181    void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
182      if (MI->getOperand(OpNo).isImmediate()) {
183        printS16ImmOperand(MI, OpNo);
184      } else {
185        O << "lo16(";
186        printOp(MI->getOperand(OpNo));
187        if (TM.getRelocationModel() == Reloc::PIC)
188          O << "-\"L" << getFunctionNumber() << "$pb\")";
189        else
190          O << ')';
191      }
192    }
193    void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
194      unsigned CCReg = MI->getOperand(OpNo).getReg();
195      unsigned RegNo = enumRegToMachineReg(CCReg);
196      O << (0x80 >> RegNo);
197    }
198    // The new addressing mode printers.
199    void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
200      printSymbolLo(MI, OpNo);
201      O << '(';
202      if (MI->getOperand(OpNo+1).isRegister() &&
203          MI->getOperand(OpNo+1).getReg() == PPC::R0)
204        O << "0";
205      else
206        printOperand(MI, OpNo+1);
207      O << ')';
208    }
209    void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) {
210      if (MI->getOperand(OpNo).isImmediate())
211        printS16X4ImmOperand(MI, OpNo);
212      else
213        printSymbolLo(MI, OpNo);
214      O << '(';
215      if (MI->getOperand(OpNo+1).isRegister() &&
216          MI->getOperand(OpNo+1).getReg() == PPC::R0)
217        O << "0";
218      else
219        printOperand(MI, OpNo+1);
220      O << ')';
221    }
222
223    void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
224      // When used as the base register, r0 reads constant zero rather than
225      // the value contained in the register.  For this reason, the darwin
226      // assembler requires that we print r0 as 0 (no r) when used as the base.
227      const MachineOperand &MO = MI->getOperand(OpNo);
228      if (MO.getReg() == PPC::R0)
229        O << '0';
230      else
231        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
232      O << ", ";
233      printOperand(MI, OpNo+1);
234    }
235
236    virtual bool runOnMachineFunction(MachineFunction &F) = 0;
237    virtual bool doFinalization(Module &M) = 0;
238
239  };
240
241  /// DarwinDwarfWriter - Dwarf debug info writer customized for Darwin/Mac OS X
242  ///
243  struct DarwinDwarfWriter : public DwarfWriter {
244    // Ctor.
245    DarwinDwarfWriter(std::ostream &o, AsmPrinter *ap)
246    : DwarfWriter(o, ap)
247    {
248      needsSet = true;
249      DwarfAbbrevSection = ".section __DWARF,__debug_abbrev";
250      DwarfInfoSection = ".section __DWARF,__debug_info";
251      DwarfLineSection = ".section __DWARF,__debug_line";
252      DwarfFrameSection = ".section __DWARF,__debug_frame";
253      DwarfPubNamesSection = ".section __DWARF,__debug_pubnames";
254      DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes";
255      DwarfStrSection = ".section __DWARF,__debug_str";
256      DwarfLocSection = ".section __DWARF,__debug_loc";
257      DwarfARangesSection = ".section __DWARF,__debug_aranges";
258      DwarfRangesSection = ".section __DWARF,__debug_ranges";
259      DwarfMacInfoSection = ".section __DWARF,__debug_macinfo";
260      TextSection = ".text";
261      DataSection = ".data";
262    }
263  };
264
265  /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
266  /// X
267  struct DarwinAsmPrinter : public PPCAsmPrinter {
268
269    DarwinDwarfWriter DW;
270
271    DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM)
272      : PPCAsmPrinter(O, TM), DW(O, this) {
273      bool isPPC64 = TM.getSubtargetImpl()->isPPC64();
274      CommentString = ";";
275      GlobalPrefix = "_";
276      PrivateGlobalPrefix = "L";     // Marker for constant pool idxs
277      ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
278      if (isPPC64)
279        Data64bitsDirective = ".quad";       // we can't emit a 64-bit unit
280      else
281        Data64bitsDirective = 0;       // we can't emit a 64-bit unit
282      AlignmentIsInBytes = false;    // Alignment is by power of 2.
283      ConstantPoolSection = "\t.const\t";
284      // FIXME: Conditionalize jump table section based on PIC
285      JumpTableSection = ".const";
286      LCOMMDirective = "\t.lcomm\t";
287      StaticCtorsSection = ".mod_init_func";
288      StaticDtorsSection = ".mod_term_func";
289      InlineAsmStart = "# InlineAsm Start";
290      InlineAsmEnd = "# InlineAsm End";
291    }
292
293    virtual const char *getPassName() const {
294      return "Darwin PPC Assembly Printer";
295    }
296
297    bool runOnMachineFunction(MachineFunction &F);
298    bool doInitialization(Module &M);
299    bool doFinalization(Module &M);
300
301    void getAnalysisUsage(AnalysisUsage &AU) const {
302      AU.setPreservesAll();
303      AU.addRequired<MachineDebugInfo>();
304      PPCAsmPrinter::getAnalysisUsage(AU);
305    }
306
307  };
308
309  /// AIXAsmPrinter - PowerPC assembly printer, customized for AIX
310  ///
311  struct AIXAsmPrinter : public PPCAsmPrinter {
312    /// Map for labels corresponding to global variables
313    ///
314    std::map<const GlobalVariable*,std::string> GVToLabelMap;
315
316    AIXAsmPrinter(std::ostream &O, TargetMachine &TM)
317      : PPCAsmPrinter(O, TM) {
318      CommentString = "#";
319      GlobalPrefix = ".";
320      ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
321      Data64bitsDirective = 0;       // we can't emit a 64-bit unit
322      AlignmentIsInBytes = false;    // Alignment is by power of 2.
323      ConstantPoolSection = "\t.const\t";
324    }
325
326    virtual const char *getPassName() const {
327      return "AIX PPC Assembly Printer";
328    }
329
330    bool runOnMachineFunction(MachineFunction &F);
331    bool doInitialization(Module &M);
332    bool doFinalization(Module &M);
333  };
334} // end of anonymous namespace
335
336/// createDarwinAsmPrinterPass - Returns a pass that prints the PPC assembly
337/// code for a MachineFunction to the given output stream, in a format that the
338/// Darwin assembler can deal with.
339///
340FunctionPass *llvm::createDarwinAsmPrinter(std::ostream &o,
341                                           PPCTargetMachine &tm) {
342  return new DarwinAsmPrinter(o, tm);
343}
344
345/// createAIXAsmPrinterPass - Returns a pass that prints the PPC assembly code
346/// for a MachineFunction to the given output stream, in a format that the
347/// AIX 5L assembler can deal with.
348///
349FunctionPass *llvm::createAIXAsmPrinter(std::ostream &o, PPCTargetMachine &tm) {
350  return new AIXAsmPrinter(o, tm);
351}
352
353// Include the auto-generated portion of the assembly writer
354#include "PPCGenAsmWriter.inc"
355
356void PPCAsmPrinter::printOp(const MachineOperand &MO) {
357  switch (MO.getType()) {
358  case MachineOperand::MO_Immediate:
359    std::cerr << "printOp() does not handle immediate values\n";
360    abort();
361    return;
362
363  case MachineOperand::MO_MachineBasicBlock:
364    printBasicBlockLabel(MO.getMachineBasicBlock());
365    return;
366  case MachineOperand::MO_JumpTableIndex:
367    O << PrivateGlobalPrefix << "JTI" << getFunctionNumber()
368      << '_' << MO.getJumpTableIndex();
369    // FIXME: PIC relocation model
370    return;
371  case MachineOperand::MO_ConstantPoolIndex:
372    O << PrivateGlobalPrefix << "CPI" << getFunctionNumber()
373      << '_' << MO.getConstantPoolIndex();
374    return;
375  case MachineOperand::MO_ExternalSymbol:
376    // Computing the address of an external symbol, not calling it.
377    if (TM.getRelocationModel() != Reloc::Static) {
378      std::string Name(GlobalPrefix); Name += MO.getSymbolName();
379      GVStubs.insert(Name);
380      O << "L" << Name << "$non_lazy_ptr";
381      return;
382    }
383    O << GlobalPrefix << MO.getSymbolName();
384    return;
385  case MachineOperand::MO_GlobalAddress: {
386    // Computing the address of a global symbol, not calling it.
387    GlobalValue *GV = MO.getGlobal();
388    std::string Name = Mang->getValueName(GV);
389    int offset = MO.getOffset();
390
391    // External or weakly linked global variables need non-lazily-resolved stubs
392    if (TM.getRelocationModel() != Reloc::Static) {
393      if (((GV->isExternal() || GV->hasWeakLinkage() ||
394            GV->hasLinkOnceLinkage()))) {
395        GVStubs.insert(Name);
396        O << "L" << Name << "$non_lazy_ptr";
397        return;
398      }
399    }
400
401    O << Name;
402    return;
403  }
404
405  default:
406    O << "<unknown operand type: " << MO.getType() << ">";
407    return;
408  }
409}
410
411/// PrintAsmOperand - Print out an operand for an inline asm expression.
412///
413bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
414                                    unsigned AsmVariant,
415                                    const char *ExtraCode) {
416  // Does this asm operand have a single letter operand modifier?
417  if (ExtraCode && ExtraCode[0]) {
418    if (ExtraCode[1] != 0) return true; // Unknown modifier.
419
420    switch (ExtraCode[0]) {
421    default: return true;  // Unknown modifier.
422    case 'L': // Write second word of DImode reference.
423      // Verify that this operand has two consecutive registers.
424      if (!MI->getOperand(OpNo).isRegister() ||
425          OpNo+1 == MI->getNumOperands() ||
426          !MI->getOperand(OpNo+1).isRegister())
427        return true;
428      ++OpNo;   // Return the high-part.
429      break;
430    }
431  }
432
433  printOperand(MI, OpNo);
434  return false;
435}
436
437bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
438                                          unsigned AsmVariant,
439                                          const char *ExtraCode) {
440  if (ExtraCode && ExtraCode[0])
441    return true; // Unknown modifier.
442  printMemRegReg(MI, OpNo);
443  return false;
444}
445
446/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
447/// the current output stream.
448///
449void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
450  ++EmittedInsts;
451
452  // Check for slwi/srwi mnemonics.
453  if (MI->getOpcode() == PPC::RLWINM) {
454    bool FoundMnemonic = false;
455    unsigned char SH = MI->getOperand(2).getImmedValue();
456    unsigned char MB = MI->getOperand(3).getImmedValue();
457    unsigned char ME = MI->getOperand(4).getImmedValue();
458    if (SH <= 31 && MB == 0 && ME == (31-SH)) {
459      O << "slwi "; FoundMnemonic = true;
460    }
461    if (SH <= 31 && MB == (32-SH) && ME == 31) {
462      O << "srwi "; FoundMnemonic = true;
463      SH = 32-SH;
464    }
465    if (FoundMnemonic) {
466      printOperand(MI, 0);
467      O << ", ";
468      printOperand(MI, 1);
469      O << ", " << (unsigned int)SH << "\n";
470      return;
471    }
472  } else if (MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) {
473    if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
474      O << "mr ";
475      printOperand(MI, 0);
476      O << ", ";
477      printOperand(MI, 1);
478      O << "\n";
479      return;
480    }
481  }
482
483  if (printInstruction(MI))
484    return; // Printer was automatically generated
485
486  assert(0 && "Unhandled instruction in asm writer!");
487  abort();
488  return;
489}
490
491/// runOnMachineFunction - This uses the printMachineInstruction()
492/// method to print assembly for each instruction.
493///
494bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
495  DW.SetDebugInfo(&getAnalysis<MachineDebugInfo>());
496
497  SetupMachineFunction(MF);
498  O << "\n\n";
499
500  // Print out constants referenced by the function
501  EmitConstantPool(MF.getConstantPool());
502
503  // Print out jump tables referenced by the function
504  EmitJumpTableInfo(MF.getJumpTableInfo());
505
506  // Print out labels for the function.
507  const Function *F = MF.getFunction();
508  switch (F->getLinkage()) {
509  default: assert(0 && "Unknown linkage type!");
510  case Function::InternalLinkage:  // Symbols default to internal.
511    SwitchToTextSection("\t.text", F);
512    break;
513  case Function::ExternalLinkage:
514    SwitchToTextSection("\t.text", F);
515    O << "\t.globl\t" << CurrentFnName << "\n";
516    break;
517  case Function::WeakLinkage:
518  case Function::LinkOnceLinkage:
519    SwitchToTextSection(
520                ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", F);
521    O << "\t.globl\t" << CurrentFnName << "\n";
522    O << "\t.weak_definition\t" << CurrentFnName << "\n";
523    break;
524  }
525  EmitAlignment(4, F);
526  O << CurrentFnName << ":\n";
527
528  // Emit pre-function debug information.
529  DW.BeginFunction(&MF);
530
531  // Print out code for the function.
532  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
533       I != E; ++I) {
534    // Print a label for the basic block.
535    if (I != MF.begin()) {
536      printBasicBlockLabel(I, true);
537      O << '\n';
538    }
539    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
540         II != E; ++II) {
541      // Print the assembly for the instruction.
542      O << "\t";
543      printMachineInstruction(II);
544    }
545  }
546
547  // Emit post-function debug information.
548  DW.EndFunction();
549
550  // We didn't modify anything.
551  return false;
552}
553
554
555bool DarwinAsmPrinter::doInitialization(Module &M) {
556  if (TM.getSubtarget<PPCSubtarget>().isGigaProcessor())
557    O << "\t.machine ppc970\n";
558  AsmPrinter::doInitialization(M);
559
560  // Darwin wants symbols to be quoted if they have complex names.
561  Mang->setUseQuotes(true);
562
563  // Emit initial debug information.
564  DW.BeginModule(&M);
565  return false;
566}
567
568bool DarwinAsmPrinter::doFinalization(Module &M) {
569  const TargetData *TD = TM.getTargetData();
570
571  // Print out module-level global variables here.
572  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
573       I != E; ++I) {
574    if (!I->hasInitializer()) continue;   // External global require no code
575
576    // Check to see if this is a special global used by LLVM, if so, emit it.
577    if (EmitSpecialLLVMGlobal(I))
578      continue;
579
580    std::string name = Mang->getValueName(I);
581    Constant *C = I->getInitializer();
582    unsigned Size = TD->getTypeSize(C->getType());
583    unsigned Align = getPreferredAlignmentLog(I);
584
585    if (C->isNullValue() && /* FIXME: Verify correct */
586        (I->hasInternalLinkage() || I->hasWeakLinkage() ||
587         I->hasLinkOnceLinkage() ||
588         (I->hasExternalLinkage() && !I->hasSection()))) {
589      if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
590      if (I->hasExternalLinkage()) {
591        O << "\t.globl " << name << '\n';
592        O << "\t.zerofill __DATA, __common, " << name << ", "
593          << Size << ", " << Align;
594      } else if (I->hasInternalLinkage()) {
595        SwitchToDataSection("\t.data", I);
596        O << LCOMMDirective << name << "," << Size << "," << Align;
597      } else {
598        SwitchToDataSection("\t.data", I);
599        O << ".comm " << name << "," << Size;
600      }
601      O << "\t\t; '" << I->getName() << "'\n";
602    } else {
603      switch (I->getLinkage()) {
604      case GlobalValue::LinkOnceLinkage:
605      case GlobalValue::WeakLinkage:
606        O << "\t.globl " << name << '\n'
607          << "\t.weak_definition " << name << '\n';
608        SwitchToDataSection(".section __DATA,__datacoal_nt,coalesced", I);
609        break;
610      case GlobalValue::AppendingLinkage:
611        // FIXME: appending linkage variables should go into a section of
612        // their name or something.  For now, just emit them as external.
613      case GlobalValue::ExternalLinkage:
614        // If external or appending, declare as a global symbol
615        O << "\t.globl " << name << "\n";
616        // FALL THROUGH
617      case GlobalValue::InternalLinkage:
618        SwitchToDataSection("\t.data", I);
619        break;
620      default:
621        std::cerr << "Unknown linkage type!";
622        abort();
623      }
624
625      EmitAlignment(Align, I);
626      O << name << ":\t\t\t\t; '" << I->getName() << "'\n";
627      EmitGlobalConstant(C);
628      O << '\n';
629    }
630  }
631
632  bool isPPC64 = TD->getPointerSizeInBits() == 64;
633
634  // Output stubs for dynamically-linked functions
635  if (TM.getRelocationModel() == Reloc::PIC) {
636    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
637         i != e; ++i) {
638      SwitchToTextSection(".section __TEXT,__picsymbolstub1,symbol_stubs,"
639                          "pure_instructions,32", 0);
640      EmitAlignment(4);
641      O << "L" << *i << "$stub:\n";
642      O << "\t.indirect_symbol " << *i << "\n";
643      O << "\tmflr r0\n";
644      O << "\tbcl 20,31,L0$" << *i << "\n";
645      O << "L0$" << *i << ":\n";
646      O << "\tmflr r11\n";
647      O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
648      O << "\tmtlr r0\n";
649      if (isPPC64)
650        O << "\tldu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
651      else
652        O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
653      O << "\tmtctr r12\n";
654      O << "\tbctr\n";
655      SwitchToDataSection(".lazy_symbol_pointer", 0);
656      O << "L" << *i << "$lazy_ptr:\n";
657      O << "\t.indirect_symbol " << *i << "\n";
658      if (isPPC64)
659        O << "\t.quad dyld_stub_binding_helper\n";
660      else
661        O << "\t.long dyld_stub_binding_helper\n";
662    }
663  } else {
664    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
665         i != e; ++i) {
666      SwitchToTextSection(".section __TEXT,__symbol_stub1,symbol_stubs,"
667                          "pure_instructions,16", 0);
668      EmitAlignment(4);
669      O << "L" << *i << "$stub:\n";
670      O << "\t.indirect_symbol " << *i << "\n";
671      O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
672      if (isPPC64)
673        O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
674      else
675        O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
676      O << "\tmtctr r12\n";
677      O << "\tbctr\n";
678      SwitchToDataSection(".lazy_symbol_pointer", 0);
679      O << "L" << *i << "$lazy_ptr:\n";
680      O << "\t.indirect_symbol " << *i << "\n";
681      if (isPPC64)
682        O << "\t.quad dyld_stub_binding_helper\n";
683      else
684        O << "\t.long dyld_stub_binding_helper\n";
685    }
686  }
687
688  O << "\n";
689
690  // Output stubs for external and common global variables.
691  if (GVStubs.begin() != GVStubs.end()) {
692    SwitchToDataSection(".non_lazy_symbol_pointer", 0);
693    for (std::set<std::string>::iterator I = GVStubs.begin(),
694         E = GVStubs.end(); I != E; ++I) {
695      O << "L" << *I << "$non_lazy_ptr:\n";
696      O << "\t.indirect_symbol " << *I << "\n";
697      O << "\t.long\t0\n";
698    }
699  }
700
701  // Emit initial debug information.
702  DW.EndModule();
703
704  // Funny Darwin hack: This flag tells the linker that no global symbols
705  // contain code that falls through to other global symbols (e.g. the obvious
706  // implementation of multiple entry points).  If this doesn't occur, the
707  // linker can safely perform dead code stripping.  Since LLVM never generates
708  // code that does this, it is always safe to set.
709  O << "\t.subsections_via_symbols\n";
710
711  AsmPrinter::doFinalization(M);
712  return false; // success
713}
714
715/// runOnMachineFunction - This uses the printMachineInstruction()
716/// method to print assembly for each instruction.
717///
718bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
719  SetupMachineFunction(MF);
720
721  // Print out constants referenced by the function
722  EmitConstantPool(MF.getConstantPool());
723
724  // Print out header for the function.
725  O << "\t.csect .text[PR]\n"
726    << "\t.align 2\n"
727    << "\t.globl "  << CurrentFnName << '\n'
728    << "\t.globl ." << CurrentFnName << '\n'
729    << "\t.csect "  << CurrentFnName << "[DS],3\n"
730    << CurrentFnName << ":\n"
731    << "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
732    << "\t.csect .text[PR]\n"
733    << '.' << CurrentFnName << ":\n";
734
735  // Print out code for the function.
736  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
737       I != E; ++I) {
738    printBasicBlockLabel(I);
739    O << '\n';
740    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
741      II != E; ++II) {
742      // Print the assembly for the instruction.
743      O << "\t";
744      printMachineInstruction(II);
745    }
746  }
747
748  O << "LT.." << CurrentFnName << ":\n"
749    << "\t.long 0\n"
750    << "\t.byte 0,0,32,65,128,0,0,0\n"
751    << "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
752    << "\t.short 3\n"
753    << "\t.byte \"" << CurrentFnName << "\"\n"
754    << "\t.align 2\n";
755
756  // We didn't modify anything.
757  return false;
758}
759
760bool AIXAsmPrinter::doInitialization(Module &M) {
761  SwitchToDataSection("", 0);
762
763  O << "\t.machine \"ppc64\"\n"
764    << "\t.toc\n"
765    << "\t.csect .text[PR]\n";
766
767  // Print out module-level global variables
768  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
769       I != E; ++I) {
770    if (!I->hasInitializer())
771      continue;
772
773    std::string Name = I->getName();
774    Constant *C = I->getInitializer();
775    // N.B.: We are defaulting to writable strings
776    if (I->hasExternalLinkage()) {
777      O << "\t.globl " << Name << '\n'
778        << "\t.csect .data[RW],3\n";
779    } else {
780      O << "\t.csect _global.rw_c[RW],3\n";
781    }
782    O << Name << ":\n";
783    EmitGlobalConstant(C);
784  }
785
786  // Output labels for globals
787  if (M.global_begin() != M.global_end()) O << "\t.toc\n";
788  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
789       I != E; ++I) {
790    const GlobalVariable *GV = I;
791    // Do not output labels for unused variables
792    if (GV->isExternal() && GV->use_begin() == GV->use_end())
793      continue;
794
795    IncrementFunctionNumber();
796    std::string Name = GV->getName();
797    std::string Label = "LC.." + utostr(getFunctionNumber());
798    GVToLabelMap[GV] = Label;
799    O << Label << ":\n"
800      << "\t.tc " << Name << "[TC]," << Name;
801    if (GV->isExternal()) O << "[RW]";
802    O << '\n';
803   }
804
805  AsmPrinter::doInitialization(M);
806  return false; // success
807}
808
809bool AIXAsmPrinter::doFinalization(Module &M) {
810  const TargetData *TD = TM.getTargetData();
811  // Print out module-level global variables
812  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
813       I != E; ++I) {
814    if (I->hasInitializer() || I->hasExternalLinkage())
815      continue;
816
817    std::string Name = I->getName();
818    if (I->hasInternalLinkage()) {
819      O << "\t.lcomm " << Name << ",16,_global.bss_c";
820    } else {
821      O << "\t.comm " << Name << "," << TD->getTypeSize(I->getType())
822        << "," << Log2_32((unsigned)TD->getTypeAlignment(I->getType()));
823    }
824    O << "\t\t" << CommentString << " ";
825    WriteAsOperand(O, I, false, true, &M);
826    O << "\n";
827  }
828
829  O << "_section_.text:\n"
830    << "\t.csect .data[RW],3\n"
831    << "\t.llong _section_.text\n";
832  AsmPrinter::doFinalization(M);
833  return false; // success
834}
835