PPCAsmPrinter.cpp revision b2efb853f00d45b1c8d57f92acd0028fbdeffda6 
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/ADT/Statistic.h"
39#include "llvm/ADT/StringExtras.h"
40#include <set>
41using namespace llvm;
42
43namespace {
44  Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
45
46  class PPCAsmPrinter : public AsmPrinter {
47  public:
48    std::set<std::string> FnStubs, GVStubs;
49
50    PPCAsmPrinter(std::ostream &O, TargetMachine &TM)
51      : AsmPrinter(O, TM) {}
52
53    virtual const char *getPassName() const {
54      return "PowerPC Assembly Printer";
55    }
56
57    PPCTargetMachine &getTM() {
58      return static_cast<PPCTargetMachine&>(TM);
59    }
60
61    unsigned enumRegToMachineReg(unsigned enumReg) {
62      switch (enumReg) {
63      default: assert(0 && "Unhandled register!"); break;
64      case PPC::CR0:  return  0;
65      case PPC::CR1:  return  1;
66      case PPC::CR2:  return  2;
67      case PPC::CR3:  return  3;
68      case PPC::CR4:  return  4;
69      case PPC::CR5:  return  5;
70      case PPC::CR6:  return  6;
71      case PPC::CR7:  return  7;
72      }
73      abort();
74    }
75
76    /// printInstruction - This method is automatically generated by tablegen
77    /// from the instruction set description.  This method returns true if the
78    /// machine instruction was sufficiently described to print it, otherwise it
79    /// returns false.
80    bool printInstruction(const MachineInstr *MI);
81
82    void printMachineInstruction(const MachineInstr *MI);
83    void printOp(const MachineOperand &MO);
84
85    void printOperand(const MachineInstr *MI, unsigned OpNo){
86      const MachineOperand &MO = MI->getOperand(OpNo);
87      if (MO.getType() == MachineOperand::MO_MachineRegister) {
88        assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
89        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
90      } else if (MO.isImmediate()) {
91        O << MO.getImmedValue();
92      } else {
93        printOp(MO);
94      }
95    }
96
97    void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
98      unsigned char value = MI->getOperand(OpNo).getImmedValue();
99      assert(value <= 31 && "Invalid u5imm argument!");
100      O << (unsigned int)value;
101    }
102    void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
103      unsigned char value = MI->getOperand(OpNo).getImmedValue();
104      assert(value <= 63 && "Invalid u6imm argument!");
105      O << (unsigned int)value;
106    }
107    void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
108      O << (short)MI->getOperand(OpNo).getImmedValue();
109    }
110    void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
111      O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
112    }
113    void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
114      O << (short)MI->getOperand(OpNo).getImmedValue()*4;
115    }
116    void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
117      // Branches can take an immediate operand.  This is used by the branch
118      // selection pass to print $+8, an eight byte displacement from the PC.
119      if (MI->getOperand(OpNo).isImmediate()) {
120        O << "$+" << MI->getOperand(OpNo).getImmedValue();
121      } else {
122        printOp(MI->getOperand(OpNo));
123      }
124    }
125    void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
126      const MachineOperand &MO = MI->getOperand(OpNo);
127      if (!PPCGenerateStaticCode) {
128        if (MO.getType() == MachineOperand::MO_GlobalAddress) {
129          GlobalValue *GV = MO.getGlobal();
130          if (((GV->isExternal() || GV->hasWeakLinkage() ||
131                GV->hasLinkOnceLinkage()))) {
132            // Dynamically-resolved functions need a stub for the function.
133            std::string Name = Mang->getValueName(GV);
134            FnStubs.insert(Name);
135            O << "L" << Name << "$stub";
136            return;
137          }
138        }
139        if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
140          std::string Name(GlobalPrefix); Name += MO.getSymbolName();
141          FnStubs.insert(Name);
142          O << "L" << Name << "$stub";
143          return;
144        }
145      }
146
147      printOp(MI->getOperand(OpNo));
148    }
149    void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
150     O << (int)MI->getOperand(OpNo).getImmedValue()*4;
151    }
152    void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
153      O << "\"L" << getFunctionNumber() << "$pb\"\n";
154      O << "\"L" << getFunctionNumber() << "$pb\":";
155    }
156    void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
157      if (MI->getOperand(OpNo).isImmediate()) {
158        printS16ImmOperand(MI, OpNo);
159      } else {
160        O << "ha16(";
161        printOp(MI->getOperand(OpNo));
162        if (PICEnabled)
163          O << "-\"L" << getFunctionNumber() << "$pb\")";
164        else
165          O << ')';
166      }
167    }
168    void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
169      if (MI->getOperand(OpNo).isImmediate()) {
170        printS16ImmOperand(MI, OpNo);
171      } else {
172        O << "lo16(";
173        printOp(MI->getOperand(OpNo));
174        if (PICEnabled)
175          O << "-\"L" << getFunctionNumber() << "$pb\")";
176        else
177          O << ')';
178      }
179    }
180    void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
181      unsigned CCReg = MI->getOperand(OpNo).getReg();
182      unsigned RegNo = enumRegToMachineReg(CCReg);
183      O << (0x80 >> RegNo);
184    }
185    // The new addressing mode printers, currently empty
186    void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
187      printSymbolLo(MI, OpNo);
188      O << '(';
189      printOperand(MI, OpNo+1);
190      O << ')';
191    }
192    void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
193      // When used as the base register, r0 reads constant zero rather than
194      // the value contained in the register.  For this reason, the darwin
195      // assembler requires that we print r0 as 0 (no r) when used as the base.
196      const MachineOperand &MO = MI->getOperand(OpNo);
197      if (MO.getReg() == PPC::R0)
198        O << '0';
199      else
200        O << TM.getRegisterInfo()->get(MO.getReg()).Name;
201      O << ", ";
202      printOperand(MI, OpNo+1);
203    }
204
205    virtual bool runOnMachineFunction(MachineFunction &F) = 0;
206    virtual bool doFinalization(Module &M) = 0;
207
208  };
209
210  /// DarwinDwarfWriter - Dwarf debug info writer customized for Darwin/Mac OS X
211  ///
212  struct DarwinDwarfWriter : public DwarfWriter {
213    // Ctor.
214    DarwinDwarfWriter(std::ostream &o, AsmPrinter *ap)
215    : DwarfWriter(o, ap)
216    {
217      needsSet = true;
218      DwarfAbbrevSection = ".section __DWARFA,__debug_abbrev,regular,debug";
219      DwarfInfoSection = ".section __DWARFA,__debug_info,regular,debug";
220      DwarfLineSection = ".section __DWARFA,__debug_line,regular,debug";
221    }
222  };
223
224  /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
225  /// X
226  ///
227  struct DarwinAsmPrinter : public PPCAsmPrinter {
228
229    DarwinDwarfWriter DW;
230
231    DarwinAsmPrinter(std::ostream &O, TargetMachine &TM)
232      : PPCAsmPrinter(O, TM), DW(O, this)
233      {
234      CommentString = ";";
235      GlobalPrefix = "_";
236      PrivateGlobalPrefix = "L";     // Marker for constant pool idxs
237      ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
238      Data64bitsDirective = 0;       // we can't emit a 64-bit unit
239      AlignmentIsInBytes = false;    // Alignment is by power of 2.
240      ConstantPoolSection = "\t.const\t";
241      LCOMMDirective = "\t.lcomm\t";
242      StaticCtorsSection = ".mod_init_func";
243      StaticDtorsSection = ".mod_term_func";
244    }
245
246    virtual const char *getPassName() const {
247      return "Darwin PPC Assembly Printer";
248    }
249
250    bool runOnMachineFunction(MachineFunction &F);
251    bool doInitialization(Module &M);
252    bool doFinalization(Module &M);
253
254    void getAnalysisUsage(AnalysisUsage &AU) const {
255      AU.addRequired<MachineDebugInfo>();
256    }
257
258  };
259
260  /// AIXAsmPrinter - PowerPC assembly printer, customized for AIX
261  ///
262  struct AIXAsmPrinter : public PPCAsmPrinter {
263    /// Map for labels corresponding to global variables
264    ///
265    std::map<const GlobalVariable*,std::string> GVToLabelMap;
266
267    AIXAsmPrinter(std::ostream &O, TargetMachine &TM)
268      : PPCAsmPrinter(O, TM) {
269      CommentString = "#";
270      GlobalPrefix = ".";
271      ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
272      Data64bitsDirective = 0;       // we can't emit a 64-bit unit
273      AlignmentIsInBytes = false;    // Alignment is by power of 2.
274      ConstantPoolSection = "\t.const\t";
275    }
276
277    virtual const char *getPassName() const {
278      return "AIX PPC Assembly Printer";
279    }
280
281    bool runOnMachineFunction(MachineFunction &F);
282    bool doInitialization(Module &M);
283    bool doFinalization(Module &M);
284  };
285} // end of anonymous namespace
286
287/// createDarwinAsmPrinterPass - Returns a pass that prints the PPC assembly
288/// code for a MachineFunction to the given output stream, in a format that the
289/// Darwin assembler can deal with.
290///
291FunctionPass *llvm::createDarwinAsmPrinter(std::ostream &o, TargetMachine &tm) {
292  return new DarwinAsmPrinter(o, tm);
293}
294
295/// createAIXAsmPrinterPass - Returns a pass that prints the PPC assembly code
296/// for a MachineFunction to the given output stream, in a format that the
297/// AIX 5L assembler can deal with.
298///
299FunctionPass *llvm::createAIXAsmPrinter(std::ostream &o, TargetMachine &tm) {
300  return new AIXAsmPrinter(o, tm);
301}
302
303// Include the auto-generated portion of the assembly writer
304#include "PPCGenAsmWriter.inc"
305
306void PPCAsmPrinter::printOp(const MachineOperand &MO) {
307  const MRegisterInfo &RI = *TM.getRegisterInfo();
308  int new_symbol;
309
310  switch (MO.getType()) {
311  case MachineOperand::MO_VirtualRegister:
312    if (Value *V = MO.getVRegValueOrNull()) {
313      O << "<" << V->getName() << ">";
314      return;
315    }
316    // FALLTHROUGH
317  case MachineOperand::MO_MachineRegister:
318  case MachineOperand::MO_CCRegister:
319    O << RI.get(MO.getReg()).Name;
320    return;
321
322  case MachineOperand::MO_SignExtendedImmed:
323  case MachineOperand::MO_UnextendedImmed:
324    std::cerr << "printOp() does not handle immediate values\n";
325    abort();
326    return;
327
328  case MachineOperand::MO_PCRelativeDisp:
329    std::cerr << "Shouldn't use addPCDisp() when building PPC MachineInstrs";
330    abort();
331    return;
332
333  case MachineOperand::MO_MachineBasicBlock: {
334    MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
335    O << PrivateGlobalPrefix << "BB" << getFunctionNumber() << "_"
336      << MBBOp->getNumber() << "\t; " << MBBOp->getBasicBlock()->getName();
337    return;
338  }
339
340  case MachineOperand::MO_ConstantPoolIndex:
341    O << PrivateGlobalPrefix << "CPI" << getFunctionNumber()
342      << '_' << MO.getConstantPoolIndex();
343    return;
344  case MachineOperand::MO_ExternalSymbol:
345    // Computing the address of an external symbol, not calling it.
346    if (!PPCGenerateStaticCode) {
347      std::string Name(GlobalPrefix); Name += MO.getSymbolName();
348      GVStubs.insert(Name);
349      O << "L" << Name << "$non_lazy_ptr";
350      return;
351    }
352    O << GlobalPrefix << MO.getSymbolName();
353    return;
354  case MachineOperand::MO_GlobalAddress: {
355    // Computing the address of a global symbol, not calling it.
356    GlobalValue *GV = MO.getGlobal();
357    std::string Name = Mang->getValueName(GV);
358    int offset = MO.getOffset();
359
360    // External or weakly linked global variables need non-lazily-resolved stubs
361    if (!PPCGenerateStaticCode) {
362      if (((GV->isExternal() || GV->hasWeakLinkage() ||
363            GV->hasLinkOnceLinkage()))) {
364        GVStubs.insert(Name);
365        O << "L" << Name << "$non_lazy_ptr";
366        return;
367      }
368    }
369
370    O << Name;
371    return;
372  }
373
374  default:
375    O << "<unknown operand type: " << MO.getType() << ">";
376    return;
377  }
378}
379
380/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
381/// the current output stream.
382///
383void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
384  ++EmittedInsts;
385
386  // Check for slwi/srwi mnemonics.
387  if (MI->getOpcode() == PPC::RLWINM) {
388    bool FoundMnemonic = false;
389    unsigned char SH = MI->getOperand(2).getImmedValue();
390    unsigned char MB = MI->getOperand(3).getImmedValue();
391    unsigned char ME = MI->getOperand(4).getImmedValue();
392    if (SH <= 31 && MB == 0 && ME == (31-SH)) {
393      O << "slwi "; FoundMnemonic = true;
394    }
395    if (SH <= 31 && MB == (32-SH) && ME == 31) {
396      O << "srwi "; FoundMnemonic = true;
397      SH = 32-SH;
398    }
399    if (FoundMnemonic) {
400      printOperand(MI, 0);
401      O << ", ";
402      printOperand(MI, 1);
403      O << ", " << (unsigned int)SH << "\n";
404      return;
405    }
406  }
407
408  if (printInstruction(MI))
409    return; // Printer was automatically generated
410
411  assert(0 && "Unhandled instruction in asm writer!");
412  abort();
413  return;
414}
415
416
417/// runOnMachineFunction - This uses the printMachineInstruction()
418/// method to print assembly for each instruction.
419///
420bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
421  SetupMachineFunction(MF);
422  O << "\n\n";
423
424  // Emit pre-function debug information.
425  DW.BeginFunction();
426
427  // Print out constants referenced by the function
428  EmitConstantPool(MF.getConstantPool());
429
430  // Print out labels for the function.
431  const Function *F = MF.getFunction();
432  switch (F->getLinkage()) {
433  default: assert(0 && "Unknown linkage type!");
434  case Function::InternalLinkage:  // Symbols default to internal.
435    SwitchSection(".text", F);
436    EmitAlignment(4, F);
437    break;
438  case Function::ExternalLinkage:
439    SwitchSection(".text", F);
440    EmitAlignment(4, F);
441    O << "\t.globl\t" << CurrentFnName << "\n";
442    break;
443  case Function::WeakLinkage:
444  case Function::LinkOnceLinkage:
445    SwitchSection(".section __TEXT,__textcoal_nt,coalesced,pure_instructions",
446                  F);
447    O << "\t.globl\t" << CurrentFnName << "\n";
448    O << "\t.weak_definition\t" << CurrentFnName << "\n";
449    break;
450  }
451  O << CurrentFnName << ":\n";
452
453  // Print out code for the function.
454  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
455       I != E; ++I) {
456    // Print a label for the basic block.
457    if (I != MF.begin()) {
458      O << PrivateGlobalPrefix << "BB" << getFunctionNumber() << '_'
459        << I->getNumber() << ":\t";
460      if (!I->getBasicBlock()->getName().empty())
461        O << CommentString << " " << I->getBasicBlock()->getName();
462      O << "\n";
463    }
464    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
465         II != E; ++II) {
466      // Print the assembly for the instruction.
467      O << "\t";
468      printMachineInstruction(II);
469    }
470  }
471
472  // Emit post-function debug information.
473  DW.EndFunction();
474
475  // We didn't modify anything.
476  return false;
477}
478
479
480bool DarwinAsmPrinter::doInitialization(Module &M) {
481  if (TM.getSubtarget<PPCSubtarget>().isGigaProcessor())
482    O << "\t.machine ppc970\n";
483  AsmPrinter::doInitialization(M);
484
485  // Darwin wants symbols to be quoted if they have complex names.
486  Mang->setUseQuotes(true);
487
488  // Emit initial debug information.
489  DW.SetDebugInfo(getAnalysisToUpdate<MachineDebugInfo>());
490  DW.BeginModule();
491  return false;
492}
493
494bool DarwinAsmPrinter::doFinalization(Module &M) {
495  const TargetData &TD = TM.getTargetData();
496
497  // Print out module-level global variables here.
498  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
499       I != E; ++I) {
500    if (!I->hasInitializer()) continue;   // External global require no code
501
502    // Check to see if this is a special global used by LLVM, if so, emit it.
503    if (I->hasAppendingLinkage() && EmitSpecialLLVMGlobal(I))
504      continue;
505
506    O << '\n';
507    std::string name = Mang->getValueName(I);
508    Constant *C = I->getInitializer();
509    unsigned Size = TD.getTypeSize(C->getType());
510    unsigned Align = TD.getTypeAlignmentShift(C->getType());
511
512    if (C->isNullValue() && /* FIXME: Verify correct */
513        (I->hasInternalLinkage() || I->hasWeakLinkage() ||
514         I->hasLinkOnceLinkage())) {
515      SwitchSection(".data", I);
516      if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
517      if (I->hasInternalLinkage())
518        O << LCOMMDirective << name << "," << Size << "," << Align;
519      else
520        O << ".comm " << name << "," << Size;
521      O << "\t\t; '" << I->getName() << "'\n";
522    } else {
523      switch (I->getLinkage()) {
524      case GlobalValue::LinkOnceLinkage:
525      case GlobalValue::WeakLinkage:
526        O << "\t.globl " << name << '\n'
527          << "\t.weak_definition " << name << '\n';
528        SwitchSection(".section __DATA,__datacoal_nt,coalesced", I);
529        break;
530      case GlobalValue::AppendingLinkage:
531        // FIXME: appending linkage variables should go into a section of
532        // their name or something.  For now, just emit them as external.
533      case GlobalValue::ExternalLinkage:
534        // If external or appending, declare as a global symbol
535        O << "\t.globl " << name << "\n";
536        // FALL THROUGH
537      case GlobalValue::InternalLinkage:
538        SwitchSection(".data", I);
539        break;
540      default:
541        std::cerr << "Unknown linkage type!";
542        abort();
543      }
544
545      EmitAlignment(Align, I);
546      O << name << ":\t\t\t\t; '" << I->getName() << "'\n";
547      EmitGlobalConstant(C);
548    }
549  }
550
551  // Output stubs for dynamically-linked functions
552  if (PICEnabled) {
553    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
554         i != e; ++i) {
555      SwitchSection(".section __TEXT,__picsymbolstub1,symbol_stubs,"
556                    "pure_instructions,32", 0);
557      EmitAlignment(2);
558      O << "L" << *i << "$stub:\n";
559      O << "\t.indirect_symbol " << *i << "\n";
560      O << "\tmflr r0\n";
561      O << "\tbcl 20,31,L0$" << *i << "\n";
562      O << "L0$" << *i << ":\n";
563      O << "\tmflr r11\n";
564      O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
565      O << "\tmtlr r0\n";
566      O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
567      O << "\tmtctr r12\n";
568      O << "\tbctr\n";
569      SwitchSection(".lazy_symbol_pointer", 0);
570      O << "L" << *i << "$lazy_ptr:\n";
571      O << "\t.indirect_symbol " << *i << "\n";
572      O << "\t.long dyld_stub_binding_helper\n";
573    }
574  } else {
575    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
576         i != e; ++i) {
577      SwitchSection(".section __TEXT,__symbol_stub1,symbol_stubs,"
578                    "pure_instructions,16", 0);
579      EmitAlignment(4);
580      O << "L" << *i << "$stub:\n";
581      O << "\t.indirect_symbol " << *i << "\n";
582      O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
583      O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
584      O << "\tmtctr r12\n";
585      O << "\tbctr\n";
586      SwitchSection(".lazy_symbol_pointer", 0);
587      O << "L" << *i << "$lazy_ptr:\n";
588      O << "\t.indirect_symbol " << *i << "\n";
589      O << "\t.long dyld_stub_binding_helper\n";
590    }
591  }
592
593  O << "\n";
594
595  // Output stubs for external and common global variables.
596  if (GVStubs.begin() != GVStubs.end()) {
597    SwitchSection(".non_lazy_symbol_pointer", 0);
598    for (std::set<std::string>::iterator I = GVStubs.begin(),
599         E = GVStubs.end(); I != E; ++I) {
600      O << "L" << *I << "$non_lazy_ptr:\n";
601      O << "\t.indirect_symbol " << *I << "\n";
602      O << "\t.long\t0\n";
603    }
604  }
605
606  // Funny Darwin hack: This flag tells the linker that no global symbols
607  // contain code that falls through to other global symbols (e.g. the obvious
608  // implementation of multiple entry points).  If this doesn't occur, the
609  // linker can safely perform dead code stripping.  Since LLVM never generates
610  // code that does this, it is always safe to set.
611  O << "\t.subsections_via_symbols\n";
612
613  // Emit initial debug information.
614  DW.EndModule();
615
616  AsmPrinter::doFinalization(M);
617  return false; // success
618}
619
620/// runOnMachineFunction - This uses the e()
621/// method to print assembly for each instruction.
622///
623bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
624  SetupMachineFunction(MF);
625
626  // Print out constants referenced by the function
627  EmitConstantPool(MF.getConstantPool());
628
629  // Print out header for the function.
630  O << "\t.csect .text[PR]\n"
631    << "\t.align 2\n"
632    << "\t.globl "  << CurrentFnName << '\n'
633    << "\t.globl ." << CurrentFnName << '\n'
634    << "\t.csect "  << CurrentFnName << "[DS],3\n"
635    << CurrentFnName << ":\n"
636    << "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
637    << "\t.csect .text[PR]\n"
638    << '.' << CurrentFnName << ":\n";
639
640  // Print out code for the function.
641  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
642       I != E; ++I) {
643    // Print a label for the basic block.
644    O << PrivateGlobalPrefix << "BB" << getFunctionNumber() << '_'
645      << I->getNumber()
646      << ":\t" << CommentString << I->getBasicBlock()->getName() << '\n';
647    for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
648      II != E; ++II) {
649      // Print the assembly for the instruction.
650      O << "\t";
651      printMachineInstruction(II);
652    }
653  }
654
655  O << "LT.." << CurrentFnName << ":\n"
656    << "\t.long 0\n"
657    << "\t.byte 0,0,32,65,128,0,0,0\n"
658    << "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
659    << "\t.short 3\n"
660    << "\t.byte \"" << CurrentFnName << "\"\n"
661    << "\t.align 2\n";
662
663  // We didn't modify anything.
664  return false;
665}
666
667bool AIXAsmPrinter::doInitialization(Module &M) {
668  SwitchSection("", 0);
669  const TargetData &TD = TM.getTargetData();
670
671  O << "\t.machine \"ppc64\"\n"
672    << "\t.toc\n"
673    << "\t.csect .text[PR]\n";
674
675  // Print out module-level global variables
676  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
677       I != E; ++I) {
678    if (!I->hasInitializer())
679      continue;
680
681    std::string Name = I->getName();
682    Constant *C = I->getInitializer();
683    // N.B.: We are defaulting to writable strings
684    if (I->hasExternalLinkage()) {
685      O << "\t.globl " << Name << '\n'
686        << "\t.csect .data[RW],3\n";
687    } else {
688      O << "\t.csect _global.rw_c[RW],3\n";
689    }
690    O << Name << ":\n";
691    EmitGlobalConstant(C);
692  }
693
694  // Output labels for globals
695  if (M.global_begin() != M.global_end()) O << "\t.toc\n";
696  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
697       I != E; ++I) {
698    const GlobalVariable *GV = I;
699    // Do not output labels for unused variables
700    if (GV->isExternal() && GV->use_begin() == GV->use_end())
701      continue;
702
703    IncrementFunctionNumber();
704    std::string Name = GV->getName();
705    std::string Label = "LC.." + utostr(getFunctionNumber());
706    GVToLabelMap[GV] = Label;
707    O << Label << ":\n"
708      << "\t.tc " << Name << "[TC]," << Name;
709    if (GV->isExternal()) O << "[RW]";
710    O << '\n';
711   }
712
713  AsmPrinter::doInitialization(M);
714  return false; // success
715}
716
717bool AIXAsmPrinter::doFinalization(Module &M) {
718  const TargetData &TD = TM.getTargetData();
719  // Print out module-level global variables
720  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
721       I != E; ++I) {
722    if (I->hasInitializer() || I->hasExternalLinkage())
723      continue;
724
725    std::string Name = I->getName();
726    if (I->hasInternalLinkage()) {
727      O << "\t.lcomm " << Name << ",16,_global.bss_c";
728    } else {
729      O << "\t.comm " << Name << "," << TD.getTypeSize(I->getType())
730        << "," << Log2_32((unsigned)TD.getTypeAlignment(I->getType()));
731    }
732    O << "\t\t" << CommentString << " ";
733    WriteAsOperand(O, I, false, true, &M);
734    O << "\n";
735  }
736
737  O << "_section_.text:\n"
738    << "\t.csect .data[RW],3\n"
739    << "\t.llong _section_.text\n";
740  AsmPrinter::doFinalization(M);
741  return false; // success
742}
743