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 #include "InstPrinter/PPCInstPrinter.h"
20 #include "MCTargetDesc/PPCMCExpr.h"
21 #include "MCTargetDesc/PPCMCTargetDesc.h"
22 #include "MCTargetDesc/PPCPredicates.h"
23 #include "PPC.h"
24 #include "PPCInstrInfo.h"
25 #include "PPCMachineFunctionInfo.h"
26 #include "PPCSubtarget.h"
27 #include "PPCTargetMachine.h"
28 #include "PPCTargetStreamer.h"
29 #include "llvm/ADT/MapVector.h"
30 #include "llvm/ADT/StringRef.h"
31 #include "llvm/ADT/Triple.h"
32 #include "llvm/ADT/Twine.h"
33 #include "llvm/BinaryFormat/ELF.h"
34 #include "llvm/BinaryFormat/MachO.h"
35 #include "llvm/CodeGen/AsmPrinter.h"
36 #include "llvm/CodeGen/MachineBasicBlock.h"
37 #include "llvm/CodeGen/MachineFunction.h"
38 #include "llvm/CodeGen/MachineInstr.h"
39 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
40 #include "llvm/CodeGen/MachineOperand.h"
41 #include "llvm/CodeGen/MachineRegisterInfo.h"
42 #include "llvm/CodeGen/StackMaps.h"
43 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
44 #include "llvm/IR/DataLayout.h"
45 #include "llvm/IR/GlobalValue.h"
46 #include "llvm/IR/Module.h"
47 #include "llvm/MC/MCAsmInfo.h"
48 #include "llvm/MC/MCContext.h"
49 #include "llvm/MC/MCExpr.h"
50 #include "llvm/MC/MCInst.h"
51 #include "llvm/MC/MCInstBuilder.h"
52 #include "llvm/MC/MCSectionELF.h"
53 #include "llvm/MC/MCSectionMachO.h"
54 #include "llvm/MC/MCStreamer.h"
55 #include "llvm/MC/MCSymbol.h"
56 #include "llvm/MC/MCSymbolELF.h"
57 #include "llvm/MC/SectionKind.h"
58 #include "llvm/Support/Casting.h"
59 #include "llvm/Support/CodeGen.h"
60 #include "llvm/Support/Debug.h"
61 #include "llvm/Support/ErrorHandling.h"
62 #include "llvm/Support/TargetRegistry.h"
63 #include "llvm/Support/raw_ostream.h"
64 #include "llvm/Target/TargetMachine.h"
65 #include <algorithm>
66 #include <cassert>
67 #include <cstdint>
68 #include <memory>
69 #include <new>
70 
71 using namespace llvm;
72 
73 #define DEBUG_TYPE "asmprinter"
74 
75 namespace {
76 
77 class PPCAsmPrinter : public AsmPrinter {
78 protected:
79   MapVector<MCSymbol *, MCSymbol *> TOC;
80   const PPCSubtarget *Subtarget;
81   StackMaps SM;
82 
83 public:
84   explicit PPCAsmPrinter(TargetMachine &TM,
85                          std::unique_ptr<MCStreamer> Streamer)
86       : AsmPrinter(TM, std::move(Streamer)), SM(*this) {}
87 
88   StringRef getPassName() const override { return "PowerPC Assembly Printer"; }
89 
90   MCSymbol *lookUpOrCreateTOCEntry(MCSymbol *Sym);
91 
92   bool doInitialization(Module &M) override {
93     if (!TOC.empty())
94       TOC.clear();
95     return AsmPrinter::doInitialization(M);
96   }
97 
98     void EmitInstruction(const MachineInstr *MI) override;
99 
100     void printOperand(const MachineInstr *MI, unsigned OpNo, raw_ostream &O);
101 
102     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
103                          unsigned AsmVariant, const char *ExtraCode,
104                          raw_ostream &O) override;
105     bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
106                                unsigned AsmVariant, const char *ExtraCode,
107                                raw_ostream &O) override;
108 
109     void EmitEndOfAsmFile(Module &M) override;
110 
111     void LowerSTACKMAP(StackMaps &SM, const MachineInstr &MI);
112     void LowerPATCHPOINT(StackMaps &SM, const MachineInstr &MI);
113     void EmitTlsCall(const MachineInstr *MI, MCSymbolRefExpr::VariantKind VK);
114     bool runOnMachineFunction(MachineFunction &MF) override {
115       Subtarget = &MF.getSubtarget<PPCSubtarget>();
116       bool Changed = AsmPrinter::runOnMachineFunction(MF);
117       emitXRayTable();
118       return Changed;
119     }
120   };
121 
122   /// PPCLinuxAsmPrinter - PowerPC assembly printer, customized for Linux
123   class PPCLinuxAsmPrinter : public PPCAsmPrinter {
124   public:
125     explicit PPCLinuxAsmPrinter(TargetMachine &TM,
126                                 std::unique_ptr<MCStreamer> Streamer)
127         : PPCAsmPrinter(TM, std::move(Streamer)) {}
128 
129     StringRef getPassName() const override {
130       return "Linux PPC Assembly Printer";
131     }
132 
133     bool doFinalization(Module &M) override;
134     void EmitStartOfAsmFile(Module &M) override;
135 
136     void EmitFunctionEntryLabel() override;
137 
138     void EmitFunctionBodyStart() override;
139     void EmitFunctionBodyEnd() override;
140     void EmitInstruction(const MachineInstr *MI) override;
141   };
142 
143   /// PPCDarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac
144   /// OS X
145   class PPCDarwinAsmPrinter : public PPCAsmPrinter {
146   public:
147     explicit PPCDarwinAsmPrinter(TargetMachine &TM,
148                                  std::unique_ptr<MCStreamer> Streamer)
149         : PPCAsmPrinter(TM, std::move(Streamer)) {}
150 
151     StringRef getPassName() const override {
152       return "Darwin PPC Assembly Printer";
153     }
154 
155     bool doFinalization(Module &M) override;
156     void EmitStartOfAsmFile(Module &M) override;
157   };
158 
159 } // end anonymous namespace
160 
161 /// stripRegisterPrefix - This method strips the character prefix from a
162 /// register name so that only the number is left.  Used by for linux asm.
163 static const char *stripRegisterPrefix(const char *RegName) {
164   switch (RegName[0]) {
165     case 'r':
166     case 'f':
167     case 'q': // for QPX
168     case 'v':
169       if (RegName[1] == 's')
170         return RegName + 2;
171       return RegName + 1;
172     case 'c': if (RegName[1] == 'r') return RegName + 2;
173   }
174 
175   return RegName;
176 }
177 
178 void PPCAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
179                                  raw_ostream &O) {
180   const DataLayout &DL = getDataLayout();
181   const MachineOperand &MO = MI->getOperand(OpNo);
182 
183   switch (MO.getType()) {
184   case MachineOperand::MO_Register: {
185     unsigned Reg = MO.getReg();
186 
187     // There are VSX instructions that use VSX register numbering (vs0 - vs63)
188     // as well as those that use VMX register numbering (v0 - v31 which
189     // correspond to vs32 - vs63). If we have an instruction that uses VSX
190     // numbering, we need to convert the VMX registers to VSX registers.
191     // Namely, we print 32-63 when the instruction operates on one of the
192     // VMX registers.
193     // (Please synchronize with PPCInstPrinter::printOperand)
194     if (MI->getDesc().TSFlags & PPCII::UseVSXReg) {
195       if (PPCInstrInfo::isVRRegister(Reg))
196         Reg = PPC::VSX32 + (Reg - PPC::V0);
197       else if (PPCInstrInfo::isVFRegister(Reg))
198         Reg = PPC::VSX32 + (Reg - PPC::VF0);
199     }
200     const char *RegName = PPCInstPrinter::getRegisterName(Reg);
201 
202     // Linux assembler (Others?) does not take register mnemonics.
203     // FIXME - What about special registers used in mfspr/mtspr?
204     if (!Subtarget->isDarwin())
205       RegName = stripRegisterPrefix(RegName);
206     O << RegName;
207     return;
208   }
209   case MachineOperand::MO_Immediate:
210     O << MO.getImm();
211     return;
212 
213   case MachineOperand::MO_MachineBasicBlock:
214     MO.getMBB()->getSymbol()->print(O, MAI);
215     return;
216   case MachineOperand::MO_ConstantPoolIndex:
217     O << DL.getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
218       << MO.getIndex();
219     return;
220   case MachineOperand::MO_BlockAddress:
221     GetBlockAddressSymbol(MO.getBlockAddress())->print(O, MAI);
222     return;
223   case MachineOperand::MO_GlobalAddress: {
224     // Computing the address of a global symbol, not calling it.
225     const GlobalValue *GV = MO.getGlobal();
226     MCSymbol *SymToPrint;
227 
228     // External or weakly linked global variables need non-lazily-resolved stubs
229     if (Subtarget->hasLazyResolverStub(GV)) {
230       SymToPrint = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
231       MachineModuleInfoImpl::StubValueTy &StubSym =
232           MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(
233               SymToPrint);
234       if (!StubSym.getPointer())
235         StubSym = MachineModuleInfoImpl::StubValueTy(getSymbol(GV),
236                                                      !GV->hasInternalLinkage());
237     } else {
238       SymToPrint = getSymbol(GV);
239     }
240 
241     SymToPrint->print(O, MAI);
242 
243     printOffset(MO.getOffset(), O);
244     return;
245   }
246 
247   default:
248     O << "<unknown operand type: " << (unsigned)MO.getType() << ">";
249     return;
250   }
251 }
252 
253 /// PrintAsmOperand - Print out an operand for an inline asm expression.
254 ///
255 bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
256                                     unsigned AsmVariant,
257                                     const char *ExtraCode, raw_ostream &O) {
258   // Does this asm operand have a single letter operand modifier?
259   if (ExtraCode && ExtraCode[0]) {
260     if (ExtraCode[1] != 0) return true; // Unknown modifier.
261 
262     switch (ExtraCode[0]) {
263     default:
264       // See if this is a generic print operand
265       return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
266     case 'c': // Don't print "$" before a global var name or constant.
267       break; // PPC never has a prefix.
268     case 'L': // Write second word of DImode reference.
269       // Verify that this operand has two consecutive registers.
270       if (!MI->getOperand(OpNo).isReg() ||
271           OpNo+1 == MI->getNumOperands() ||
272           !MI->getOperand(OpNo+1).isReg())
273         return true;
274       ++OpNo;   // Return the high-part.
275       break;
276     case 'I':
277       // Write 'i' if an integer constant, otherwise nothing.  Used to print
278       // addi vs add, etc.
279       if (MI->getOperand(OpNo).isImm())
280         O << "i";
281       return false;
282     }
283   }
284 
285   printOperand(MI, OpNo, O);
286   return false;
287 }
288 
289 // At the moment, all inline asm memory operands are a single register.
290 // In any case, the output of this routine should always be just one
291 // assembler operand.
292 
293 bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
294                                           unsigned AsmVariant,
295                                           const char *ExtraCode,
296                                           raw_ostream &O) {
297   if (ExtraCode && ExtraCode[0]) {
298     if (ExtraCode[1] != 0) return true; // Unknown modifier.
299 
300     switch (ExtraCode[0]) {
301     default: return true;  // Unknown modifier.
302     case 'y': // A memory reference for an X-form instruction
303       {
304         const char *RegName = "r0";
305         if (!Subtarget->isDarwin())
306           RegName = stripRegisterPrefix(RegName);
307         O << RegName << ", ";
308         printOperand(MI, OpNo, O);
309         return false;
310       }
311     case 'U': // Print 'u' for update form.
312     case 'X': // Print 'x' for indexed form.
313     {
314       // FIXME: Currently for PowerPC memory operands are always loaded
315       // into a register, so we never get an update or indexed form.
316       // This is bad even for offset forms, since even if we know we
317       // have a value in -16(r1), we will generate a load into r<n>
318       // and then load from 0(r<n>).  Until that issue is fixed,
319       // tolerate 'U' and 'X' but don't output anything.
320       assert(MI->getOperand(OpNo).isReg());
321       return false;
322     }
323     }
324   }
325 
326   assert(MI->getOperand(OpNo).isReg());
327   O << "0(";
328   printOperand(MI, OpNo, O);
329   O << ")";
330   return false;
331 }
332 
333 /// lookUpOrCreateTOCEntry -- Given a symbol, look up whether a TOC entry
334 /// exists for it.  If not, create one.  Then return a symbol that references
335 /// the TOC entry.
336 MCSymbol *PPCAsmPrinter::lookUpOrCreateTOCEntry(MCSymbol *Sym) {
337   MCSymbol *&TOCEntry = TOC[Sym];
338   if (!TOCEntry)
339     TOCEntry = createTempSymbol("C");
340   return TOCEntry;
341 }
342 
343 void PPCAsmPrinter::EmitEndOfAsmFile(Module &M) {
344   SM.serializeToStackMapSection();
345 }
346 
347 void PPCAsmPrinter::LowerSTACKMAP(StackMaps &SM, const MachineInstr &MI) {
348   unsigned NumNOPBytes = MI.getOperand(1).getImm();
349 
350   SM.recordStackMap(MI);
351   assert(NumNOPBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
352 
353   // Scan ahead to trim the shadow.
354   const MachineBasicBlock &MBB = *MI.getParent();
355   MachineBasicBlock::const_iterator MII(MI);
356   ++MII;
357   while (NumNOPBytes > 0) {
358     if (MII == MBB.end() || MII->isCall() ||
359         MII->getOpcode() == PPC::DBG_VALUE ||
360         MII->getOpcode() == TargetOpcode::PATCHPOINT ||
361         MII->getOpcode() == TargetOpcode::STACKMAP)
362       break;
363     ++MII;
364     NumNOPBytes -= 4;
365   }
366 
367   // Emit nops.
368   for (unsigned i = 0; i < NumNOPBytes; i += 4)
369     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
370 }
371 
372 // Lower a patchpoint of the form:
373 // [<def>], <id>, <numBytes>, <target>, <numArgs>
374 void PPCAsmPrinter::LowerPATCHPOINT(StackMaps &SM, const MachineInstr &MI) {
375   SM.recordPatchPoint(MI);
376   PatchPointOpers Opers(&MI);
377 
378   unsigned EncodedBytes = 0;
379   const MachineOperand &CalleeMO = Opers.getCallTarget();
380 
381   if (CalleeMO.isImm()) {
382     int64_t CallTarget = CalleeMO.getImm();
383     if (CallTarget) {
384       assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget &&
385              "High 16 bits of call target should be zero.");
386       unsigned ScratchReg = MI.getOperand(Opers.getNextScratchIdx()).getReg();
387       EncodedBytes = 0;
388       // Materialize the jump address:
389       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LI8)
390                                       .addReg(ScratchReg)
391                                       .addImm((CallTarget >> 32) & 0xFFFF));
392       ++EncodedBytes;
393       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::RLDIC)
394                                       .addReg(ScratchReg)
395                                       .addReg(ScratchReg)
396                                       .addImm(32).addImm(16));
397       ++EncodedBytes;
398       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ORIS8)
399                                       .addReg(ScratchReg)
400                                       .addReg(ScratchReg)
401                                       .addImm((CallTarget >> 16) & 0xFFFF));
402       ++EncodedBytes;
403       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ORI8)
404                                       .addReg(ScratchReg)
405                                       .addReg(ScratchReg)
406                                       .addImm(CallTarget & 0xFFFF));
407 
408       // Save the current TOC pointer before the remote call.
409       int TOCSaveOffset = Subtarget->getFrameLowering()->getTOCSaveOffset();
410       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::STD)
411                                       .addReg(PPC::X2)
412                                       .addImm(TOCSaveOffset)
413                                       .addReg(PPC::X1));
414       ++EncodedBytes;
415 
416       // If we're on ELFv1, then we need to load the actual function pointer
417       // from the function descriptor.
418       if (!Subtarget->isELFv2ABI()) {
419         // Load the new TOC pointer and the function address, but not r11
420         // (needing this is rare, and loading it here would prevent passing it
421         // via a 'nest' parameter.
422         EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
423                                         .addReg(PPC::X2)
424                                         .addImm(8)
425                                         .addReg(ScratchReg));
426         ++EncodedBytes;
427         EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
428                                         .addReg(ScratchReg)
429                                         .addImm(0)
430                                         .addReg(ScratchReg));
431         ++EncodedBytes;
432       }
433 
434       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTCTR8)
435                                       .addReg(ScratchReg));
436       ++EncodedBytes;
437       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BCTRL8));
438       ++EncodedBytes;
439 
440       // Restore the TOC pointer after the call.
441       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
442                                       .addReg(PPC::X2)
443                                       .addImm(TOCSaveOffset)
444                                       .addReg(PPC::X1));
445       ++EncodedBytes;
446     }
447   } else if (CalleeMO.isGlobal()) {
448     const GlobalValue *GValue = CalleeMO.getGlobal();
449     MCSymbol *MOSymbol = getSymbol(GValue);
450     const MCExpr *SymVar = MCSymbolRefExpr::create(MOSymbol, OutContext);
451 
452     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL8_NOP)
453                                     .addExpr(SymVar));
454     EncodedBytes += 2;
455   }
456 
457   // Each instruction is 4 bytes.
458   EncodedBytes *= 4;
459 
460   // Emit padding.
461   unsigned NumBytes = Opers.getNumPatchBytes();
462   assert(NumBytes >= EncodedBytes &&
463          "Patchpoint can't request size less than the length of a call.");
464   assert((NumBytes - EncodedBytes) % 4 == 0 &&
465          "Invalid number of NOP bytes requested!");
466   for (unsigned i = EncodedBytes; i < NumBytes; i += 4)
467     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
468 }
469 
470 /// EmitTlsCall -- Given a GETtls[ld]ADDR[32] instruction, print a
471 /// call to __tls_get_addr to the current output stream.
472 void PPCAsmPrinter::EmitTlsCall(const MachineInstr *MI,
473                                 MCSymbolRefExpr::VariantKind VK) {
474   StringRef Name = "__tls_get_addr";
475   MCSymbol *TlsGetAddr = OutContext.getOrCreateSymbol(Name);
476   MCSymbolRefExpr::VariantKind Kind = MCSymbolRefExpr::VK_None;
477 
478   assert(MI->getOperand(0).isReg() &&
479          ((Subtarget->isPPC64() && MI->getOperand(0).getReg() == PPC::X3) ||
480           (!Subtarget->isPPC64() && MI->getOperand(0).getReg() == PPC::R3)) &&
481          "GETtls[ld]ADDR[32] must define GPR3");
482   assert(MI->getOperand(1).isReg() &&
483          ((Subtarget->isPPC64() && MI->getOperand(1).getReg() == PPC::X3) ||
484           (!Subtarget->isPPC64() && MI->getOperand(1).getReg() == PPC::R3)) &&
485          "GETtls[ld]ADDR[32] must read GPR3");
486 
487   if (!Subtarget->isPPC64() && !Subtarget->isDarwin() &&
488       isPositionIndependent())
489     Kind = MCSymbolRefExpr::VK_PLT;
490   const MCSymbolRefExpr *TlsRef =
491     MCSymbolRefExpr::create(TlsGetAddr, Kind, OutContext);
492   const MachineOperand &MO = MI->getOperand(2);
493   const GlobalValue *GValue = MO.getGlobal();
494   MCSymbol *MOSymbol = getSymbol(GValue);
495   const MCExpr *SymVar = MCSymbolRefExpr::create(MOSymbol, VK, OutContext);
496   EmitToStreamer(*OutStreamer,
497                  MCInstBuilder(Subtarget->isPPC64() ?
498                                PPC::BL8_NOP_TLS : PPC::BL_TLS)
499                  .addExpr(TlsRef)
500                  .addExpr(SymVar));
501 }
502 
503 /// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
504 /// the current output stream.
505 ///
506 void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
507   MCInst TmpInst;
508   bool isPPC64 = Subtarget->isPPC64();
509   bool isDarwin = TM.getTargetTriple().isOSDarwin();
510   const Module *M = MF->getFunction().getParent();
511   PICLevel::Level PL = M->getPICLevel();
512 
513   // Lower multi-instruction pseudo operations.
514   switch (MI->getOpcode()) {
515   default: break;
516   case TargetOpcode::DBG_VALUE:
517     llvm_unreachable("Should be handled target independently");
518   case TargetOpcode::STACKMAP:
519     return LowerSTACKMAP(SM, *MI);
520   case TargetOpcode::PATCHPOINT:
521     return LowerPATCHPOINT(SM, *MI);
522 
523   case PPC::MoveGOTtoLR: {
524     // Transform %lr = MoveGOTtoLR
525     // Into this: bl _GLOBAL_OFFSET_TABLE_@local-4
526     // _GLOBAL_OFFSET_TABLE_@local-4 (instruction preceding
527     // _GLOBAL_OFFSET_TABLE_) has exactly one instruction:
528     //      blrl
529     // This will return the pointer to _GLOBAL_OFFSET_TABLE_@local
530     MCSymbol *GOTSymbol =
531       OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
532     const MCExpr *OffsExpr =
533       MCBinaryExpr::createSub(MCSymbolRefExpr::create(GOTSymbol,
534                                                       MCSymbolRefExpr::VK_PPC_LOCAL,
535                                                       OutContext),
536                               MCConstantExpr::create(4, OutContext),
537                               OutContext);
538 
539     // Emit the 'bl'.
540     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL).addExpr(OffsExpr));
541     return;
542   }
543   case PPC::MovePCtoLR:
544   case PPC::MovePCtoLR8: {
545     // Transform %lr = MovePCtoLR
546     // Into this, where the label is the PIC base:
547     //     bl L1$pb
548     // L1$pb:
549     MCSymbol *PICBase = MF->getPICBaseSymbol();
550 
551     // Emit the 'bl'.
552     EmitToStreamer(*OutStreamer,
553                    MCInstBuilder(PPC::BL)
554                        // FIXME: We would like an efficient form for this, so we
555                        // don't have to do a lot of extra uniquing.
556                        .addExpr(MCSymbolRefExpr::create(PICBase, OutContext)));
557 
558     // Emit the label.
559     OutStreamer->EmitLabel(PICBase);
560     return;
561   }
562   case PPC::UpdateGBR: {
563     // Transform %rd = UpdateGBR(%rt, %ri)
564     // Into: lwz %rt, .L0$poff - .L0$pb(%ri)
565     //       add %rd, %rt, %ri
566     // Get the offset from the GOT Base Register to the GOT
567     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
568     MCSymbol *PICOffset =
569       MF->getInfo<PPCFunctionInfo>()->getPICOffsetSymbol();
570     TmpInst.setOpcode(PPC::LWZ);
571     const MCExpr *Exp =
572       MCSymbolRefExpr::create(PICOffset, MCSymbolRefExpr::VK_None, OutContext);
573     const MCExpr *PB =
574       MCSymbolRefExpr::create(MF->getPICBaseSymbol(),
575                               MCSymbolRefExpr::VK_None,
576                               OutContext);
577     const MCOperand TR = TmpInst.getOperand(1);
578     const MCOperand PICR = TmpInst.getOperand(0);
579 
580     // Step 1: lwz %rt, .L$poff - .L$pb(%ri)
581     TmpInst.getOperand(1) =
582         MCOperand::createExpr(MCBinaryExpr::createSub(Exp, PB, OutContext));
583     TmpInst.getOperand(0) = TR;
584     TmpInst.getOperand(2) = PICR;
585     EmitToStreamer(*OutStreamer, TmpInst);
586 
587     TmpInst.setOpcode(PPC::ADD4);
588     TmpInst.getOperand(0) = PICR;
589     TmpInst.getOperand(1) = TR;
590     TmpInst.getOperand(2) = PICR;
591     EmitToStreamer(*OutStreamer, TmpInst);
592     return;
593   }
594   case PPC::LWZtoc: {
595     // Transform %r3 = LWZtoc @min1, %r2
596     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
597 
598     // Change the opcode to LWZ, and the global address operand to be a
599     // reference to the GOT entry we will synthesize later.
600     TmpInst.setOpcode(PPC::LWZ);
601     const MachineOperand &MO = MI->getOperand(1);
602 
603     // Map symbol -> label of TOC entry
604     assert(MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress());
605     MCSymbol *MOSymbol = nullptr;
606     if (MO.isGlobal())
607       MOSymbol = getSymbol(MO.getGlobal());
608     else if (MO.isCPI())
609       MOSymbol = GetCPISymbol(MO.getIndex());
610     else if (MO.isJTI())
611       MOSymbol = GetJTISymbol(MO.getIndex());
612     else if (MO.isBlockAddress())
613       MOSymbol = GetBlockAddressSymbol(MO.getBlockAddress());
614 
615     if (PL == PICLevel::SmallPIC) {
616       const MCExpr *Exp =
617         MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_GOT,
618                                 OutContext);
619       TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
620     } else {
621       MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol);
622 
623       const MCExpr *Exp =
624         MCSymbolRefExpr::create(TOCEntry, MCSymbolRefExpr::VK_None,
625                                 OutContext);
626       const MCExpr *PB =
627         MCSymbolRefExpr::create(OutContext.getOrCreateSymbol(Twine(".LTOC")),
628                                                              OutContext);
629       Exp = MCBinaryExpr::createSub(Exp, PB, OutContext);
630       TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
631     }
632     EmitToStreamer(*OutStreamer, TmpInst);
633     return;
634   }
635   case PPC::LDtocJTI:
636   case PPC::LDtocCPT:
637   case PPC::LDtocBA:
638   case PPC::LDtoc: {
639     // Transform %x3 = LDtoc @min1, %x2
640     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
641 
642     // Change the opcode to LD, and the global address operand to be a
643     // reference to the TOC entry we will synthesize later.
644     TmpInst.setOpcode(PPC::LD);
645     const MachineOperand &MO = MI->getOperand(1);
646 
647     // Map symbol -> label of TOC entry
648     assert(MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress());
649     MCSymbol *MOSymbol = nullptr;
650     if (MO.isGlobal())
651       MOSymbol = getSymbol(MO.getGlobal());
652     else if (MO.isCPI())
653       MOSymbol = GetCPISymbol(MO.getIndex());
654     else if (MO.isJTI())
655       MOSymbol = GetJTISymbol(MO.getIndex());
656     else if (MO.isBlockAddress())
657       MOSymbol = GetBlockAddressSymbol(MO.getBlockAddress());
658 
659     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol);
660 
661     const MCExpr *Exp =
662       MCSymbolRefExpr::create(TOCEntry, MCSymbolRefExpr::VK_PPC_TOC,
663                               OutContext);
664     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
665     EmitToStreamer(*OutStreamer, TmpInst);
666     return;
667   }
668 
669   case PPC::ADDIStocHA: {
670     // Transform %xd = ADDIStocHA %x2, @sym
671     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
672 
673     // Change the opcode to ADDIS8.  If the global address is external, has
674     // common linkage, is a non-local function address, or is a jump table
675     // address, then generate a TOC entry and reference that.  Otherwise
676     // reference the symbol directly.
677     TmpInst.setOpcode(PPC::ADDIS8);
678     const MachineOperand &MO = MI->getOperand(2);
679     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() ||
680             MO.isBlockAddress()) &&
681            "Invalid operand for ADDIStocHA!");
682     MCSymbol *MOSymbol = nullptr;
683     bool GlobalToc = false;
684 
685     if (MO.isGlobal()) {
686       const GlobalValue *GV = MO.getGlobal();
687       MOSymbol = getSymbol(GV);
688       unsigned char GVFlags = Subtarget->classifyGlobalReference(GV);
689       GlobalToc = (GVFlags & PPCII::MO_NLP_FLAG);
690     } else if (MO.isCPI()) {
691       MOSymbol = GetCPISymbol(MO.getIndex());
692     } else if (MO.isJTI()) {
693       MOSymbol = GetJTISymbol(MO.getIndex());
694     } else if (MO.isBlockAddress()) {
695       MOSymbol = GetBlockAddressSymbol(MO.getBlockAddress());
696     }
697 
698     if (GlobalToc || MO.isJTI() || MO.isBlockAddress() ||
699         TM.getCodeModel() == CodeModel::Large)
700       MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
701 
702     const MCExpr *Exp =
703       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_HA,
704                               OutContext);
705 
706     if (!MO.isJTI() && MO.getOffset())
707       Exp = MCBinaryExpr::createAdd(Exp,
708                                     MCConstantExpr::create(MO.getOffset(),
709                                                            OutContext),
710                                     OutContext);
711 
712     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
713     EmitToStreamer(*OutStreamer, TmpInst);
714     return;
715   }
716   case PPC::LDtocL: {
717     // Transform %xd = LDtocL @sym, %xs
718     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
719 
720     // Change the opcode to LD.  If the global address is external, has
721     // common linkage, or is a jump table address, then reference the
722     // associated TOC entry.  Otherwise reference the symbol directly.
723     TmpInst.setOpcode(PPC::LD);
724     const MachineOperand &MO = MI->getOperand(1);
725     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() ||
726             MO.isBlockAddress()) &&
727            "Invalid operand for LDtocL!");
728     MCSymbol *MOSymbol = nullptr;
729 
730     if (MO.isJTI())
731       MOSymbol = lookUpOrCreateTOCEntry(GetJTISymbol(MO.getIndex()));
732     else if (MO.isBlockAddress()) {
733       MOSymbol = GetBlockAddressSymbol(MO.getBlockAddress());
734       MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
735     }
736     else if (MO.isCPI()) {
737       MOSymbol = GetCPISymbol(MO.getIndex());
738       if (TM.getCodeModel() == CodeModel::Large)
739         MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
740     }
741     else if (MO.isGlobal()) {
742       const GlobalValue *GV = MO.getGlobal();
743       MOSymbol = getSymbol(GV);
744       DEBUG(
745         unsigned char GVFlags = Subtarget->classifyGlobalReference(GV);
746         assert((GVFlags & PPCII::MO_NLP_FLAG) &&
747                "LDtocL used on symbol that could be accessed directly is "
748                "invalid. Must match ADDIStocHA."));
749       MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
750     }
751 
752     const MCExpr *Exp =
753       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_LO,
754                               OutContext);
755     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
756     EmitToStreamer(*OutStreamer, TmpInst);
757     return;
758   }
759   case PPC::ADDItocL: {
760     // Transform %xd = ADDItocL %xs, @sym
761     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
762 
763     // Change the opcode to ADDI8.  If the global address is external, then
764     // generate a TOC entry and reference that.  Otherwise reference the
765     // symbol directly.
766     TmpInst.setOpcode(PPC::ADDI8);
767     const MachineOperand &MO = MI->getOperand(2);
768     assert((MO.isGlobal() || MO.isCPI()) && "Invalid operand for ADDItocL");
769     MCSymbol *MOSymbol = nullptr;
770 
771     if (MO.isGlobal()) {
772       const GlobalValue *GV = MO.getGlobal();
773       DEBUG(
774         unsigned char GVFlags = Subtarget->classifyGlobalReference(GV);
775         assert (
776             !(GVFlags & PPCII::MO_NLP_FLAG) &&
777             "Interposable definitions must use indirect access."));
778       MOSymbol = getSymbol(GV);
779     } else if (MO.isCPI()) {
780       MOSymbol = GetCPISymbol(MO.getIndex());
781     }
782 
783     const MCExpr *Exp =
784       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_LO,
785                               OutContext);
786     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
787     EmitToStreamer(*OutStreamer, TmpInst);
788     return;
789   }
790   case PPC::ADDISgotTprelHA: {
791     // Transform: %xd = ADDISgotTprelHA %x2, @sym
792     // Into:      %xd = ADDIS8 %x2, sym@got@tlsgd@ha
793     assert(Subtarget->isPPC64() && "Not supported for 32-bit PowerPC");
794     const MachineOperand &MO = MI->getOperand(2);
795     const GlobalValue *GValue = MO.getGlobal();
796     MCSymbol *MOSymbol = getSymbol(GValue);
797     const MCExpr *SymGotTprel =
798       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA,
799                               OutContext);
800     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
801                                  .addReg(MI->getOperand(0).getReg())
802                                  .addReg(MI->getOperand(1).getReg())
803                                  .addExpr(SymGotTprel));
804     return;
805   }
806   case PPC::LDgotTprelL:
807   case PPC::LDgotTprelL32: {
808     // Transform %xd = LDgotTprelL @sym, %xs
809     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
810 
811     // Change the opcode to LD.
812     TmpInst.setOpcode(isPPC64 ? PPC::LD : PPC::LWZ);
813     const MachineOperand &MO = MI->getOperand(1);
814     const GlobalValue *GValue = MO.getGlobal();
815     MCSymbol *MOSymbol = getSymbol(GValue);
816     const MCExpr *Exp =
817       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO,
818                               OutContext);
819     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
820     EmitToStreamer(*OutStreamer, TmpInst);
821     return;
822   }
823 
824   case PPC::PPC32PICGOT: {
825     MCSymbol *GOTSymbol = OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
826     MCSymbol *GOTRef = OutContext.createTempSymbol();
827     MCSymbol *NextInstr = OutContext.createTempSymbol();
828 
829     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL)
830       // FIXME: We would like an efficient form for this, so we don't have to do
831       // a lot of extra uniquing.
832       .addExpr(MCSymbolRefExpr::create(NextInstr, OutContext)));
833     const MCExpr *OffsExpr =
834       MCBinaryExpr::createSub(MCSymbolRefExpr::create(GOTSymbol, OutContext),
835                                 MCSymbolRefExpr::create(GOTRef, OutContext),
836         OutContext);
837     OutStreamer->EmitLabel(GOTRef);
838     OutStreamer->EmitValue(OffsExpr, 4);
839     OutStreamer->EmitLabel(NextInstr);
840     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR)
841                                  .addReg(MI->getOperand(0).getReg()));
842     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LWZ)
843                                  .addReg(MI->getOperand(1).getReg())
844                                  .addImm(0)
845                                  .addReg(MI->getOperand(0).getReg()));
846     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADD4)
847                                  .addReg(MI->getOperand(0).getReg())
848                                  .addReg(MI->getOperand(1).getReg())
849                                  .addReg(MI->getOperand(0).getReg()));
850     return;
851   }
852   case PPC::PPC32GOT: {
853     MCSymbol *GOTSymbol =
854         OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
855     const MCExpr *SymGotTlsL = MCSymbolRefExpr::create(
856         GOTSymbol, MCSymbolRefExpr::VK_PPC_LO, OutContext);
857     const MCExpr *SymGotTlsHA = MCSymbolRefExpr::create(
858         GOTSymbol, MCSymbolRefExpr::VK_PPC_HA, OutContext);
859     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LI)
860                                  .addReg(MI->getOperand(0).getReg())
861                                  .addExpr(SymGotTlsL));
862     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS)
863                                  .addReg(MI->getOperand(0).getReg())
864                                  .addReg(MI->getOperand(0).getReg())
865                                  .addExpr(SymGotTlsHA));
866     return;
867   }
868   case PPC::ADDIStlsgdHA: {
869     // Transform: %xd = ADDIStlsgdHA %x2, @sym
870     // Into:      %xd = ADDIS8 %x2, sym@got@tlsgd@ha
871     assert(Subtarget->isPPC64() && "Not supported for 32-bit PowerPC");
872     const MachineOperand &MO = MI->getOperand(2);
873     const GlobalValue *GValue = MO.getGlobal();
874     MCSymbol *MOSymbol = getSymbol(GValue);
875     const MCExpr *SymGotTlsGD =
876       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA,
877                               OutContext);
878     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
879                                  .addReg(MI->getOperand(0).getReg())
880                                  .addReg(MI->getOperand(1).getReg())
881                                  .addExpr(SymGotTlsGD));
882     return;
883   }
884   case PPC::ADDItlsgdL:
885     // Transform: %xd = ADDItlsgdL %xs, @sym
886     // Into:      %xd = ADDI8 %xs, sym@got@tlsgd@l
887   case PPC::ADDItlsgdL32: {
888     // Transform: %rd = ADDItlsgdL32 %rs, @sym
889     // Into:      %rd = ADDI %rs, sym@got@tlsgd
890     const MachineOperand &MO = MI->getOperand(2);
891     const GlobalValue *GValue = MO.getGlobal();
892     MCSymbol *MOSymbol = getSymbol(GValue);
893     const MCExpr *SymGotTlsGD = MCSymbolRefExpr::create(
894         MOSymbol, Subtarget->isPPC64() ? MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO
895                                        : MCSymbolRefExpr::VK_PPC_GOT_TLSGD,
896         OutContext);
897     EmitToStreamer(*OutStreamer,
898                    MCInstBuilder(Subtarget->isPPC64() ? PPC::ADDI8 : PPC::ADDI)
899                    .addReg(MI->getOperand(0).getReg())
900                    .addReg(MI->getOperand(1).getReg())
901                    .addExpr(SymGotTlsGD));
902     return;
903   }
904   case PPC::GETtlsADDR:
905     // Transform: %x3 = GETtlsADDR %x3, @sym
906     // Into: BL8_NOP_TLS __tls_get_addr(sym at tlsgd)
907   case PPC::GETtlsADDR32: {
908     // Transform: %r3 = GETtlsADDR32 %r3, @sym
909     // Into: BL_TLS __tls_get_addr(sym at tlsgd)@PLT
910     EmitTlsCall(MI, MCSymbolRefExpr::VK_PPC_TLSGD);
911     return;
912   }
913   case PPC::ADDIStlsldHA: {
914     // Transform: %xd = ADDIStlsldHA %x2, @sym
915     // Into:      %xd = ADDIS8 %x2, sym@got@tlsld@ha
916     assert(Subtarget->isPPC64() && "Not supported for 32-bit PowerPC");
917     const MachineOperand &MO = MI->getOperand(2);
918     const GlobalValue *GValue = MO.getGlobal();
919     MCSymbol *MOSymbol = getSymbol(GValue);
920     const MCExpr *SymGotTlsLD =
921       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA,
922                               OutContext);
923     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
924                                  .addReg(MI->getOperand(0).getReg())
925                                  .addReg(MI->getOperand(1).getReg())
926                                  .addExpr(SymGotTlsLD));
927     return;
928   }
929   case PPC::ADDItlsldL:
930     // Transform: %xd = ADDItlsldL %xs, @sym
931     // Into:      %xd = ADDI8 %xs, sym@got@tlsld@l
932   case PPC::ADDItlsldL32: {
933     // Transform: %rd = ADDItlsldL32 %rs, @sym
934     // Into:      %rd = ADDI %rs, sym@got@tlsld
935     const MachineOperand &MO = MI->getOperand(2);
936     const GlobalValue *GValue = MO.getGlobal();
937     MCSymbol *MOSymbol = getSymbol(GValue);
938     const MCExpr *SymGotTlsLD = MCSymbolRefExpr::create(
939         MOSymbol, Subtarget->isPPC64() ? MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO
940                                        : MCSymbolRefExpr::VK_PPC_GOT_TLSLD,
941         OutContext);
942     EmitToStreamer(*OutStreamer,
943                    MCInstBuilder(Subtarget->isPPC64() ? PPC::ADDI8 : PPC::ADDI)
944                        .addReg(MI->getOperand(0).getReg())
945                        .addReg(MI->getOperand(1).getReg())
946                        .addExpr(SymGotTlsLD));
947     return;
948   }
949   case PPC::GETtlsldADDR:
950     // Transform: %x3 = GETtlsldADDR %x3, @sym
951     // Into: BL8_NOP_TLS __tls_get_addr(sym at tlsld)
952   case PPC::GETtlsldADDR32: {
953     // Transform: %r3 = GETtlsldADDR32 %r3, @sym
954     // Into: BL_TLS __tls_get_addr(sym at tlsld)@PLT
955     EmitTlsCall(MI, MCSymbolRefExpr::VK_PPC_TLSLD);
956     return;
957   }
958   case PPC::ADDISdtprelHA:
959     // Transform: %xd = ADDISdtprelHA %xs, @sym
960     // Into:      %xd = ADDIS8 %xs, sym@dtprel@ha
961   case PPC::ADDISdtprelHA32: {
962     // Transform: %rd = ADDISdtprelHA32 %rs, @sym
963     // Into:      %rd = ADDIS %rs, sym@dtprel@ha
964     const MachineOperand &MO = MI->getOperand(2);
965     const GlobalValue *GValue = MO.getGlobal();
966     MCSymbol *MOSymbol = getSymbol(GValue);
967     const MCExpr *SymDtprel =
968       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_HA,
969                               OutContext);
970     EmitToStreamer(
971         *OutStreamer,
972         MCInstBuilder(Subtarget->isPPC64() ? PPC::ADDIS8 : PPC::ADDIS)
973             .addReg(MI->getOperand(0).getReg())
974             .addReg(MI->getOperand(1).getReg())
975             .addExpr(SymDtprel));
976     return;
977   }
978   case PPC::ADDIdtprelL:
979     // Transform: %xd = ADDIdtprelL %xs, @sym
980     // Into:      %xd = ADDI8 %xs, sym@dtprel@l
981   case PPC::ADDIdtprelL32: {
982     // Transform: %rd = ADDIdtprelL32 %rs, @sym
983     // Into:      %rd = ADDI %rs, sym@dtprel@l
984     const MachineOperand &MO = MI->getOperand(2);
985     const GlobalValue *GValue = MO.getGlobal();
986     MCSymbol *MOSymbol = getSymbol(GValue);
987     const MCExpr *SymDtprel =
988       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_LO,
989                               OutContext);
990     EmitToStreamer(*OutStreamer,
991                    MCInstBuilder(Subtarget->isPPC64() ? PPC::ADDI8 : PPC::ADDI)
992                        .addReg(MI->getOperand(0).getReg())
993                        .addReg(MI->getOperand(1).getReg())
994                        .addExpr(SymDtprel));
995     return;
996   }
997   case PPC::MFOCRF:
998   case PPC::MFOCRF8:
999     if (!Subtarget->hasMFOCRF()) {
1000       // Transform: %r3 = MFOCRF %cr7
1001       // Into:      %r3 = MFCR   ;; cr7
1002       unsigned NewOpcode =
1003         MI->getOpcode() == PPC::MFOCRF ? PPC::MFCR : PPC::MFCR8;
1004       OutStreamer->AddComment(PPCInstPrinter::
1005                               getRegisterName(MI->getOperand(1).getReg()));
1006       EmitToStreamer(*OutStreamer, MCInstBuilder(NewOpcode)
1007                                   .addReg(MI->getOperand(0).getReg()));
1008       return;
1009     }
1010     break;
1011   case PPC::MTOCRF:
1012   case PPC::MTOCRF8:
1013     if (!Subtarget->hasMFOCRF()) {
1014       // Transform: %cr7 = MTOCRF %r3
1015       // Into:      MTCRF mask, %r3 ;; cr7
1016       unsigned NewOpcode =
1017         MI->getOpcode() == PPC::MTOCRF ? PPC::MTCRF : PPC::MTCRF8;
1018       unsigned Mask = 0x80 >> OutContext.getRegisterInfo()
1019                               ->getEncodingValue(MI->getOperand(0).getReg());
1020       OutStreamer->AddComment(PPCInstPrinter::
1021                               getRegisterName(MI->getOperand(0).getReg()));
1022       EmitToStreamer(*OutStreamer, MCInstBuilder(NewOpcode)
1023                                      .addImm(Mask)
1024                                      .addReg(MI->getOperand(1).getReg()));
1025       return;
1026     }
1027     break;
1028   case PPC::LD:
1029   case PPC::STD:
1030   case PPC::LWA_32:
1031   case PPC::LWA: {
1032     // Verify alignment is legal, so we don't create relocations
1033     // that can't be supported.
1034     // FIXME:  This test is currently disabled for Darwin.  The test
1035     // suite shows a handful of test cases that fail this check for
1036     // Darwin.  Those need to be investigated before this sanity test
1037     // can be enabled for those subtargets.
1038     if (!Subtarget->isDarwin()) {
1039       unsigned OpNum = (MI->getOpcode() == PPC::STD) ? 2 : 1;
1040       const MachineOperand &MO = MI->getOperand(OpNum);
1041       if (MO.isGlobal() && MO.getGlobal()->getAlignment() < 4)
1042         llvm_unreachable("Global must be word-aligned for LD, STD, LWA!");
1043     }
1044     // Now process the instruction normally.
1045     break;
1046   }
1047   }
1048 
1049   LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, isDarwin);
1050   EmitToStreamer(*OutStreamer, TmpInst);
1051 }
1052 
1053 void PPCLinuxAsmPrinter::EmitInstruction(const MachineInstr *MI) {
1054   if (!Subtarget->isPPC64())
1055     return PPCAsmPrinter::EmitInstruction(MI);
1056 
1057   switch (MI->getOpcode()) {
1058   default:
1059     return PPCAsmPrinter::EmitInstruction(MI);
1060   case TargetOpcode::PATCHABLE_FUNCTION_ENTER: {
1061     // .begin:
1062     //   b .end # lis 0, FuncId[16..32]
1063     //   nop    # li  0, FuncId[0..15]
1064     //   std 0, -8(1)
1065     //   mflr 0
1066     //   bl __xray_FunctionEntry
1067     //   mtlr 0
1068     // .end:
1069     //
1070     // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1071     // of instructions change.
1072     MCSymbol *BeginOfSled = OutContext.createTempSymbol();
1073     MCSymbol *EndOfSled = OutContext.createTempSymbol();
1074     OutStreamer->EmitLabel(BeginOfSled);
1075     EmitToStreamer(*OutStreamer,
1076                    MCInstBuilder(PPC::B).addExpr(
1077                        MCSymbolRefExpr::create(EndOfSled, OutContext)));
1078     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
1079     EmitToStreamer(
1080         *OutStreamer,
1081         MCInstBuilder(PPC::STD).addReg(PPC::X0).addImm(-8).addReg(PPC::X1));
1082     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR8).addReg(PPC::X0));
1083     EmitToStreamer(*OutStreamer,
1084                    MCInstBuilder(PPC::BL8_NOP)
1085                        .addExpr(MCSymbolRefExpr::create(
1086                            OutContext.getOrCreateSymbol("__xray_FunctionEntry"),
1087                            OutContext)));
1088     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTLR8).addReg(PPC::X0));
1089     OutStreamer->EmitLabel(EndOfSled);
1090     recordSled(BeginOfSled, *MI, SledKind::FUNCTION_ENTER);
1091     break;
1092   }
1093   case TargetOpcode::PATCHABLE_RET: {
1094     unsigned RetOpcode = MI->getOperand(0).getImm();
1095     MCInst RetInst;
1096     RetInst.setOpcode(RetOpcode);
1097     for (const auto &MO :
1098          make_range(std::next(MI->operands_begin()), MI->operands_end())) {
1099       MCOperand MCOp;
1100       if (LowerPPCMachineOperandToMCOperand(MO, MCOp, *this, false))
1101         RetInst.addOperand(MCOp);
1102     }
1103 
1104     bool IsConditional;
1105     if (RetOpcode == PPC::BCCLR) {
1106       IsConditional = true;
1107     } else if (RetOpcode == PPC::TCRETURNdi8 || RetOpcode == PPC::TCRETURNri8 ||
1108                RetOpcode == PPC::TCRETURNai8) {
1109       break;
1110     } else if (RetOpcode == PPC::BLR8 || RetOpcode == PPC::TAILB8) {
1111       IsConditional = false;
1112     } else {
1113       EmitToStreamer(*OutStreamer, RetInst);
1114       break;
1115     }
1116 
1117     MCSymbol *FallthroughLabel;
1118     if (IsConditional) {
1119       // Before:
1120       //   bgtlr cr0
1121       //
1122       // After:
1123       //   ble cr0, .end
1124       // .p2align 3
1125       // .begin:
1126       //   blr    # lis 0, FuncId[16..32]
1127       //   nop    # li  0, FuncId[0..15]
1128       //   std 0, -8(1)
1129       //   mflr 0
1130       //   bl __xray_FunctionExit
1131       //   mtlr 0
1132       //   blr
1133       // .end:
1134       //
1135       // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1136       // of instructions change.
1137       FallthroughLabel = OutContext.createTempSymbol();
1138       EmitToStreamer(
1139           *OutStreamer,
1140           MCInstBuilder(PPC::BCC)
1141               .addImm(PPC::InvertPredicate(
1142                   static_cast<PPC::Predicate>(MI->getOperand(1).getImm())))
1143               .addReg(MI->getOperand(2).getReg())
1144               .addExpr(MCSymbolRefExpr::create(FallthroughLabel, OutContext)));
1145       RetInst = MCInst();
1146       RetInst.setOpcode(PPC::BLR8);
1147     }
1148     // .p2align 3
1149     // .begin:
1150     //   b(lr)? # lis 0, FuncId[16..32]
1151     //   nop    # li  0, FuncId[0..15]
1152     //   std 0, -8(1)
1153     //   mflr 0
1154     //   bl __xray_FunctionExit
1155     //   mtlr 0
1156     //   b(lr)?
1157     //
1158     // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1159     // of instructions change.
1160     OutStreamer->EmitCodeAlignment(8);
1161     MCSymbol *BeginOfSled = OutContext.createTempSymbol();
1162     OutStreamer->EmitLabel(BeginOfSled);
1163     EmitToStreamer(*OutStreamer, RetInst);
1164     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
1165     EmitToStreamer(
1166         *OutStreamer,
1167         MCInstBuilder(PPC::STD).addReg(PPC::X0).addImm(-8).addReg(PPC::X1));
1168     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR8).addReg(PPC::X0));
1169     EmitToStreamer(*OutStreamer,
1170                    MCInstBuilder(PPC::BL8_NOP)
1171                        .addExpr(MCSymbolRefExpr::create(
1172                            OutContext.getOrCreateSymbol("__xray_FunctionExit"),
1173                            OutContext)));
1174     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTLR8).addReg(PPC::X0));
1175     EmitToStreamer(*OutStreamer, RetInst);
1176     if (IsConditional)
1177       OutStreamer->EmitLabel(FallthroughLabel);
1178     recordSled(BeginOfSled, *MI, SledKind::FUNCTION_EXIT);
1179     break;
1180   }
1181   case TargetOpcode::PATCHABLE_FUNCTION_EXIT:
1182     llvm_unreachable("PATCHABLE_FUNCTION_EXIT should never be emitted");
1183   case TargetOpcode::PATCHABLE_TAIL_CALL:
1184     // TODO: Define a trampoline `__xray_FunctionTailExit` and differentiate a
1185     // normal function exit from a tail exit.
1186     llvm_unreachable("Tail call is handled in the normal case. See comments "
1187                      "around this assert.");
1188   }
1189 }
1190 
1191 void PPCLinuxAsmPrinter::EmitStartOfAsmFile(Module &M) {
1192   if (static_cast<const PPCTargetMachine &>(TM).isELFv2ABI()) {
1193     PPCTargetStreamer *TS =
1194       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1195 
1196     if (TS)
1197       TS->emitAbiVersion(2);
1198   }
1199 
1200   if (static_cast<const PPCTargetMachine &>(TM).isPPC64() ||
1201       !isPositionIndependent())
1202     return AsmPrinter::EmitStartOfAsmFile(M);
1203 
1204   if (M.getPICLevel() == PICLevel::SmallPIC)
1205     return AsmPrinter::EmitStartOfAsmFile(M);
1206 
1207   OutStreamer->SwitchSection(OutContext.getELFSection(
1208       ".got2", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC));
1209 
1210   MCSymbol *TOCSym = OutContext.getOrCreateSymbol(Twine(".LTOC"));
1211   MCSymbol *CurrentPos = OutContext.createTempSymbol();
1212 
1213   OutStreamer->EmitLabel(CurrentPos);
1214 
1215   // The GOT pointer points to the middle of the GOT, in order to reference the
1216   // entire 64kB range.  0x8000 is the midpoint.
1217   const MCExpr *tocExpr =
1218     MCBinaryExpr::createAdd(MCSymbolRefExpr::create(CurrentPos, OutContext),
1219                             MCConstantExpr::create(0x8000, OutContext),
1220                             OutContext);
1221 
1222   OutStreamer->EmitAssignment(TOCSym, tocExpr);
1223 
1224   OutStreamer->SwitchSection(getObjFileLowering().getTextSection());
1225 }
1226 
1227 void PPCLinuxAsmPrinter::EmitFunctionEntryLabel() {
1228   // linux/ppc32 - Normal entry label.
1229   if (!Subtarget->isPPC64() &&
1230       (!isPositionIndependent() ||
1231        MF->getFunction().getParent()->getPICLevel() == PICLevel::SmallPIC))
1232     return AsmPrinter::EmitFunctionEntryLabel();
1233 
1234   if (!Subtarget->isPPC64()) {
1235     const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1236     if (PPCFI->usesPICBase()) {
1237       MCSymbol *RelocSymbol = PPCFI->getPICOffsetSymbol();
1238       MCSymbol *PICBase = MF->getPICBaseSymbol();
1239       OutStreamer->EmitLabel(RelocSymbol);
1240 
1241       const MCExpr *OffsExpr =
1242         MCBinaryExpr::createSub(
1243           MCSymbolRefExpr::create(OutContext.getOrCreateSymbol(Twine(".LTOC")),
1244                                                                OutContext),
1245                                   MCSymbolRefExpr::create(PICBase, OutContext),
1246           OutContext);
1247       OutStreamer->EmitValue(OffsExpr, 4);
1248       OutStreamer->EmitLabel(CurrentFnSym);
1249       return;
1250     } else
1251       return AsmPrinter::EmitFunctionEntryLabel();
1252   }
1253 
1254   // ELFv2 ABI - Normal entry label.
1255   if (Subtarget->isELFv2ABI()) {
1256     // In the Large code model, we allow arbitrary displacements between
1257     // the text section and its associated TOC section.  We place the
1258     // full 8-byte offset to the TOC in memory immediatedly preceding
1259     // the function global entry point.
1260     if (TM.getCodeModel() == CodeModel::Large
1261         && !MF->getRegInfo().use_empty(PPC::X2)) {
1262       const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1263 
1264       MCSymbol *TOCSymbol = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1265       MCSymbol *GlobalEPSymbol = PPCFI->getGlobalEPSymbol();
1266       const MCExpr *TOCDeltaExpr =
1267         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCSymbol, OutContext),
1268                                 MCSymbolRefExpr::create(GlobalEPSymbol,
1269                                                         OutContext),
1270                                 OutContext);
1271 
1272       OutStreamer->EmitLabel(PPCFI->getTOCOffsetSymbol());
1273       OutStreamer->EmitValue(TOCDeltaExpr, 8);
1274     }
1275     return AsmPrinter::EmitFunctionEntryLabel();
1276   }
1277 
1278   // Emit an official procedure descriptor.
1279   MCSectionSubPair Current = OutStreamer->getCurrentSection();
1280   MCSectionELF *Section = OutStreamer->getContext().getELFSection(
1281       ".opd", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
1282   OutStreamer->SwitchSection(Section);
1283   OutStreamer->EmitLabel(CurrentFnSym);
1284   OutStreamer->EmitValueToAlignment(8);
1285   MCSymbol *Symbol1 = CurrentFnSymForSize;
1286   // Generates a R_PPC64_ADDR64 (from FK_DATA_8) relocation for the function
1287   // entry point.
1288   OutStreamer->EmitValue(MCSymbolRefExpr::create(Symbol1, OutContext),
1289                          8 /*size*/);
1290   MCSymbol *Symbol2 = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1291   // Generates a R_PPC64_TOC relocation for TOC base insertion.
1292   OutStreamer->EmitValue(
1293     MCSymbolRefExpr::create(Symbol2, MCSymbolRefExpr::VK_PPC_TOCBASE, OutContext),
1294     8/*size*/);
1295   // Emit a null environment pointer.
1296   OutStreamer->EmitIntValue(0, 8 /* size */);
1297   OutStreamer->SwitchSection(Current.first, Current.second);
1298 }
1299 
1300 bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
1301   const DataLayout &DL = getDataLayout();
1302 
1303   bool isPPC64 = DL.getPointerSizeInBits() == 64;
1304 
1305   PPCTargetStreamer &TS =
1306       static_cast<PPCTargetStreamer &>(*OutStreamer->getTargetStreamer());
1307 
1308   if (!TOC.empty()) {
1309     MCSectionELF *Section;
1310 
1311     if (isPPC64)
1312       Section = OutStreamer->getContext().getELFSection(
1313           ".toc", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
1314         else
1315           Section = OutStreamer->getContext().getELFSection(
1316               ".got2", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
1317     OutStreamer->SwitchSection(Section);
1318 
1319     for (MapVector<MCSymbol*, MCSymbol*>::iterator I = TOC.begin(),
1320          E = TOC.end(); I != E; ++I) {
1321       OutStreamer->EmitLabel(I->second);
1322       MCSymbol *S = I->first;
1323       if (isPPC64) {
1324         TS.emitTCEntry(*S);
1325       } else {
1326         OutStreamer->EmitValueToAlignment(4);
1327         OutStreamer->EmitSymbolValue(S, 4);
1328       }
1329     }
1330   }
1331 
1332   return AsmPrinter::doFinalization(M);
1333 }
1334 
1335 /// EmitFunctionBodyStart - Emit a global entry point prefix for ELFv2.
1336 void PPCLinuxAsmPrinter::EmitFunctionBodyStart() {
1337   // In the ELFv2 ABI, in functions that use the TOC register, we need to
1338   // provide two entry points.  The ABI guarantees that when calling the
1339   // local entry point, r2 is set up by the caller to contain the TOC base
1340   // for this function, and when calling the global entry point, r12 is set
1341   // up by the caller to hold the address of the global entry point.  We
1342   // thus emit a prefix sequence along the following lines:
1343   //
1344   // func:
1345   // .Lfunc_gepNN:
1346   //         # global entry point
1347   //         addis r2,r12,(.TOC.-.Lfunc_gepNN)@ha
1348   //         addi  r2,r2,(.TOC.-.Lfunc_gepNN)@l
1349   // .Lfunc_lepNN:
1350   //         .localentry func, .Lfunc_lepNN-.Lfunc_gepNN
1351   //         # local entry point, followed by function body
1352   //
1353   // For the Large code model, we create
1354   //
1355   // .Lfunc_tocNN:
1356   //         .quad .TOC.-.Lfunc_gepNN      # done by EmitFunctionEntryLabel
1357   // func:
1358   // .Lfunc_gepNN:
1359   //         # global entry point
1360   //         ld    r2,.Lfunc_tocNN-.Lfunc_gepNN(r12)
1361   //         add   r2,r2,r12
1362   // .Lfunc_lepNN:
1363   //         .localentry func, .Lfunc_lepNN-.Lfunc_gepNN
1364   //         # local entry point, followed by function body
1365   //
1366   // This ensures we have r2 set up correctly while executing the function
1367   // body, no matter which entry point is called.
1368   if (Subtarget->isELFv2ABI()
1369       // Only do all that if the function uses r2 in the first place.
1370       && !MF->getRegInfo().use_empty(PPC::X2)) {
1371     // Note: The logic here must be synchronized with the code in the
1372     // branch-selection pass which sets the offset of the first block in the
1373     // function. This matters because it affects the alignment.
1374     const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1375 
1376     MCSymbol *GlobalEntryLabel = PPCFI->getGlobalEPSymbol();
1377     OutStreamer->EmitLabel(GlobalEntryLabel);
1378     const MCSymbolRefExpr *GlobalEntryLabelExp =
1379       MCSymbolRefExpr::create(GlobalEntryLabel, OutContext);
1380 
1381     if (TM.getCodeModel() != CodeModel::Large) {
1382       MCSymbol *TOCSymbol = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1383       const MCExpr *TOCDeltaExpr =
1384         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCSymbol, OutContext),
1385                                 GlobalEntryLabelExp, OutContext);
1386 
1387       const MCExpr *TOCDeltaHi =
1388         PPCMCExpr::createHa(TOCDeltaExpr, false, OutContext);
1389       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS)
1390                                    .addReg(PPC::X2)
1391                                    .addReg(PPC::X12)
1392                                    .addExpr(TOCDeltaHi));
1393 
1394       const MCExpr *TOCDeltaLo =
1395         PPCMCExpr::createLo(TOCDeltaExpr, false, OutContext);
1396       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDI)
1397                                    .addReg(PPC::X2)
1398                                    .addReg(PPC::X2)
1399                                    .addExpr(TOCDeltaLo));
1400     } else {
1401       MCSymbol *TOCOffset = PPCFI->getTOCOffsetSymbol();
1402       const MCExpr *TOCOffsetDeltaExpr =
1403         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCOffset, OutContext),
1404                                 GlobalEntryLabelExp, OutContext);
1405 
1406       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
1407                                    .addReg(PPC::X2)
1408                                    .addExpr(TOCOffsetDeltaExpr)
1409                                    .addReg(PPC::X12));
1410       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADD8)
1411                                    .addReg(PPC::X2)
1412                                    .addReg(PPC::X2)
1413                                    .addReg(PPC::X12));
1414     }
1415 
1416     MCSymbol *LocalEntryLabel = PPCFI->getLocalEPSymbol();
1417     OutStreamer->EmitLabel(LocalEntryLabel);
1418     const MCSymbolRefExpr *LocalEntryLabelExp =
1419        MCSymbolRefExpr::create(LocalEntryLabel, OutContext);
1420     const MCExpr *LocalOffsetExp =
1421       MCBinaryExpr::createSub(LocalEntryLabelExp,
1422                               GlobalEntryLabelExp, OutContext);
1423 
1424     PPCTargetStreamer *TS =
1425       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1426 
1427     if (TS)
1428       TS->emitLocalEntry(cast<MCSymbolELF>(CurrentFnSym), LocalOffsetExp);
1429   }
1430 }
1431 
1432 /// EmitFunctionBodyEnd - Print the traceback table before the .size
1433 /// directive.
1434 ///
1435 void PPCLinuxAsmPrinter::EmitFunctionBodyEnd() {
1436   // Only the 64-bit target requires a traceback table.  For now,
1437   // we only emit the word of zeroes that GDB requires to find
1438   // the end of the function, and zeroes for the eight-byte
1439   // mandatory fields.
1440   // FIXME: We should fill in the eight-byte mandatory fields as described in
1441   // the PPC64 ELF ABI (this is a low-priority item because GDB does not
1442   // currently make use of these fields).
1443   if (Subtarget->isPPC64()) {
1444     OutStreamer->EmitIntValue(0, 4/*size*/);
1445     OutStreamer->EmitIntValue(0, 8/*size*/);
1446   }
1447 }
1448 
1449 void PPCDarwinAsmPrinter::EmitStartOfAsmFile(Module &M) {
1450   static const char *const CPUDirectives[] = {
1451     "",
1452     "ppc",
1453     "ppc440",
1454     "ppc601",
1455     "ppc602",
1456     "ppc603",
1457     "ppc7400",
1458     "ppc750",
1459     "ppc970",
1460     "ppcA2",
1461     "ppce500mc",
1462     "ppce5500",
1463     "power3",
1464     "power4",
1465     "power5",
1466     "power5x",
1467     "power6",
1468     "power6x",
1469     "power7",
1470     // FIXME: why is power8 missing here?
1471     "ppc64",
1472     "ppc64le",
1473     "power9"
1474   };
1475 
1476   // Get the numerically largest directive.
1477   // FIXME: How should we merge darwin directives?
1478   unsigned Directive = PPC::DIR_NONE;
1479   for (const Function &F : M) {
1480     const PPCSubtarget &STI = TM.getSubtarget<PPCSubtarget>(F);
1481     unsigned FDir = STI.getDarwinDirective();
1482     Directive = Directive > FDir ? FDir : STI.getDarwinDirective();
1483     if (STI.hasMFOCRF() && Directive < PPC::DIR_970)
1484       Directive = PPC::DIR_970;
1485     if (STI.hasAltivec() && Directive < PPC::DIR_7400)
1486       Directive = PPC::DIR_7400;
1487     if (STI.isPPC64() && Directive < PPC::DIR_64)
1488       Directive = PPC::DIR_64;
1489   }
1490 
1491   assert(Directive <= PPC::DIR_64 && "Directive out of range.");
1492 
1493   assert(Directive < array_lengthof(CPUDirectives) &&
1494          "CPUDirectives[] might not be up-to-date!");
1495   PPCTargetStreamer &TStreamer =
1496       *static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1497   TStreamer.emitMachine(CPUDirectives[Directive]);
1498 
1499   // Prime text sections so they are adjacent.  This reduces the likelihood a
1500   // large data or debug section causes a branch to exceed 16M limit.
1501   const TargetLoweringObjectFileMachO &TLOFMacho =
1502       static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
1503   OutStreamer->SwitchSection(TLOFMacho.getTextCoalSection());
1504   if (TM.getRelocationModel() == Reloc::PIC_) {
1505     OutStreamer->SwitchSection(
1506            OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
1507                                       MachO::S_SYMBOL_STUBS |
1508                                       MachO::S_ATTR_PURE_INSTRUCTIONS,
1509                                       32, SectionKind::getText()));
1510   } else if (TM.getRelocationModel() == Reloc::DynamicNoPIC) {
1511     OutStreamer->SwitchSection(
1512            OutContext.getMachOSection("__TEXT","__symbol_stub1",
1513                                       MachO::S_SYMBOL_STUBS |
1514                                       MachO::S_ATTR_PURE_INSTRUCTIONS,
1515                                       16, SectionKind::getText()));
1516   }
1517   OutStreamer->SwitchSection(getObjFileLowering().getTextSection());
1518 }
1519 
1520 bool PPCDarwinAsmPrinter::doFinalization(Module &M) {
1521   bool isPPC64 = getDataLayout().getPointerSizeInBits() == 64;
1522 
1523   // Darwin/PPC always uses mach-o.
1524   const TargetLoweringObjectFileMachO &TLOFMacho =
1525       static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
1526   if (MMI) {
1527     MachineModuleInfoMachO &MMIMacho =
1528         MMI->getObjFileInfo<MachineModuleInfoMachO>();
1529 
1530     if (MAI->doesSupportExceptionHandling()) {
1531       // Add the (possibly multiple) personalities to the set of global values.
1532       // Only referenced functions get into the Personalities list.
1533       for (const Function *Personality : MMI->getPersonalities()) {
1534         if (Personality) {
1535           MCSymbol *NLPSym =
1536               getSymbolWithGlobalValueBase(Personality, "$non_lazy_ptr");
1537           MachineModuleInfoImpl::StubValueTy &StubSym =
1538               MMIMacho.getGVStubEntry(NLPSym);
1539           StubSym =
1540               MachineModuleInfoImpl::StubValueTy(getSymbol(Personality), true);
1541         }
1542       }
1543     }
1544 
1545     // Output stubs for dynamically-linked functions.
1546     MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetGVStubList();
1547 
1548     // Output macho stubs for external and common global variables.
1549     if (!Stubs.empty()) {
1550       // Switch with ".non_lazy_symbol_pointer" directive.
1551       OutStreamer->SwitchSection(TLOFMacho.getNonLazySymbolPointerSection());
1552       EmitAlignment(isPPC64 ? 3 : 2);
1553 
1554       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
1555         // L_foo$stub:
1556         OutStreamer->EmitLabel(Stubs[i].first);
1557         //   .indirect_symbol _foo
1558         MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
1559         OutStreamer->EmitSymbolAttribute(MCSym.getPointer(),
1560                                          MCSA_IndirectSymbol);
1561 
1562         if (MCSym.getInt())
1563           // External to current translation unit.
1564           OutStreamer->EmitIntValue(0, isPPC64 ? 8 : 4 /*size*/);
1565         else
1566           // Internal to current translation unit.
1567           //
1568           // When we place the LSDA into the TEXT section, the type info
1569           // pointers
1570           // need to be indirect and pc-rel. We accomplish this by using NLPs.
1571           // However, sometimes the types are local to the file. So we need to
1572           // fill in the value for the NLP in those cases.
1573           OutStreamer->EmitValue(
1574               MCSymbolRefExpr::create(MCSym.getPointer(), OutContext),
1575               isPPC64 ? 8 : 4 /*size*/);
1576       }
1577 
1578       Stubs.clear();
1579       OutStreamer->AddBlankLine();
1580     }
1581   }
1582 
1583   // Funny Darwin hack: This flag tells the linker that no global symbols
1584   // contain code that falls through to other global symbols (e.g. the obvious
1585   // implementation of multiple entry points).  If this doesn't occur, the
1586   // linker can safely perform dead code stripping.  Since LLVM never generates
1587   // code that does this, it is always safe to set.
1588   OutStreamer->EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
1589 
1590   return AsmPrinter::doFinalization(M);
1591 }
1592 
1593 /// createPPCAsmPrinterPass - Returns a pass that prints the PPC assembly code
1594 /// for a MachineFunction to the given output stream, in a format that the
1595 /// Darwin assembler can deal with.
1596 ///
1597 static AsmPrinter *
1598 createPPCAsmPrinterPass(TargetMachine &tm,
1599                         std::unique_ptr<MCStreamer> &&Streamer) {
1600   if (tm.getTargetTriple().isMacOSX())
1601     return new PPCDarwinAsmPrinter(tm, std::move(Streamer));
1602   return new PPCLinuxAsmPrinter(tm, std::move(Streamer));
1603 }
1604 
1605 // Force static initialization.
1606 extern "C" void LLVMInitializePowerPCAsmPrinter() {
1607   TargetRegistry::RegisterAsmPrinter(getThePPC32Target(),
1608                                      createPPCAsmPrinterPass);
1609   TargetRegistry::RegisterAsmPrinter(getThePPC64Target(),
1610                                      createPPCAsmPrinterPass);
1611   TargetRegistry::RegisterAsmPrinter(getThePPC64LETarget(),
1612                                      createPPCAsmPrinterPass);
1613 }
1614