xref: /freebsd/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp (revision ac175bd33a21b7f357cffe37117dc5afa6d7c5fb)
1 //===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly ------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains a printer that converts from our internal representation
10 // of machine-dependent LLVM code to PowerPC assembly language. This printer is
11 // the output mechanism used by `llc'.
12 //
13 // Documentation at http://developer.apple.com/documentation/DeveloperTools/
14 // Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "MCTargetDesc/PPCInstPrinter.h"
19 #include "MCTargetDesc/PPCMCExpr.h"
20 #include "MCTargetDesc/PPCMCTargetDesc.h"
21 #include "MCTargetDesc/PPCPredicates.h"
22 #include "PPC.h"
23 #include "PPCInstrInfo.h"
24 #include "PPCMachineFunctionInfo.h"
25 #include "PPCSubtarget.h"
26 #include "PPCTargetMachine.h"
27 #include "PPCTargetStreamer.h"
28 #include "TargetInfo/PowerPCTargetInfo.h"
29 #include "llvm/ADT/MapVector.h"
30 #include "llvm/ADT/SmallPtrSet.h"
31 #include "llvm/ADT/StringRef.h"
32 #include "llvm/ADT/Triple.h"
33 #include "llvm/ADT/Twine.h"
34 #include "llvm/BinaryFormat/ELF.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/GlobalVariable.h"
47 #include "llvm/IR/Module.h"
48 #include "llvm/MC/MCAsmInfo.h"
49 #include "llvm/MC/MCContext.h"
50 #include "llvm/MC/MCDirectives.h"
51 #include "llvm/MC/MCExpr.h"
52 #include "llvm/MC/MCInst.h"
53 #include "llvm/MC/MCInstBuilder.h"
54 #include "llvm/MC/MCSectionELF.h"
55 #include "llvm/MC/MCSectionXCOFF.h"
56 #include "llvm/MC/MCStreamer.h"
57 #include "llvm/MC/MCSymbol.h"
58 #include "llvm/MC/MCSymbolELF.h"
59 #include "llvm/MC/MCSymbolXCOFF.h"
60 #include "llvm/MC/SectionKind.h"
61 #include "llvm/MC/TargetRegistry.h"
62 #include "llvm/Support/Casting.h"
63 #include "llvm/Support/CodeGen.h"
64 #include "llvm/Support/Debug.h"
65 #include "llvm/Support/Error.h"
66 #include "llvm/Support/ErrorHandling.h"
67 #include "llvm/Support/Process.h"
68 #include "llvm/Support/raw_ostream.h"
69 #include "llvm/Target/TargetMachine.h"
70 #include "llvm/Transforms/Utils/ModuleUtils.h"
71 #include <algorithm>
72 #include <cassert>
73 #include <cstdint>
74 #include <memory>
75 #include <new>
76 
77 using namespace llvm;
78 using namespace llvm::XCOFF;
79 
80 #define DEBUG_TYPE "asmprinter"
81 
82 static cl::opt<bool> EnableSSPCanaryBitInTB(
83     "aix-ssp-tb-bit", cl::init(false),
84     cl::desc("Enable Passing SSP Canary info in Trackback on AIX"), cl::Hidden);
85 
86 // Specialize DenseMapInfo to allow
87 // std::pair<const MCSymbol *, MCSymbolRefExpr::VariantKind> in DenseMap.
88 // This specialization is needed here because that type is used as keys in the
89 // map representing TOC entries.
90 namespace llvm {
91 template <>
92 struct DenseMapInfo<std::pair<const MCSymbol *, MCSymbolRefExpr::VariantKind>> {
93   using TOCKey = std::pair<const MCSymbol *, MCSymbolRefExpr::VariantKind>;
94 
95   static inline TOCKey getEmptyKey() {
96     return {nullptr, MCSymbolRefExpr::VariantKind::VK_None};
97   }
98   static inline TOCKey getTombstoneKey() {
99     return {nullptr, MCSymbolRefExpr::VariantKind::VK_Invalid};
100   }
101   static unsigned getHashValue(const TOCKey &PairVal) {
102     return detail::combineHashValue(
103         DenseMapInfo<const MCSymbol *>::getHashValue(PairVal.first),
104         DenseMapInfo<int>::getHashValue(PairVal.second));
105   }
106   static bool isEqual(const TOCKey &A, const TOCKey &B) { return A == B; }
107 };
108 } // end namespace llvm
109 
110 namespace {
111 
112 enum {
113   // GNU attribute tags for PowerPC ABI
114   Tag_GNU_Power_ABI_FP = 4,
115   Tag_GNU_Power_ABI_Vector = 8,
116   Tag_GNU_Power_ABI_Struct_Return = 12,
117 
118   // GNU attribute values for PowerPC float ABI, as combination of two parts
119   Val_GNU_Power_ABI_NoFloat = 0b00,
120   Val_GNU_Power_ABI_HardFloat_DP = 0b01,
121   Val_GNU_Power_ABI_SoftFloat_DP = 0b10,
122   Val_GNU_Power_ABI_HardFloat_SP = 0b11,
123 
124   Val_GNU_Power_ABI_LDBL_IBM128 = 0b0100,
125   Val_GNU_Power_ABI_LDBL_64 = 0b1000,
126   Val_GNU_Power_ABI_LDBL_IEEE128 = 0b1100,
127 };
128 
129 class PPCAsmPrinter : public AsmPrinter {
130 protected:
131   // For TLS on AIX, we need to be able to identify TOC entries of specific
132   // VariantKind so we can add the right relocations when we generate the
133   // entries. So each entry is represented by a pair of MCSymbol and
134   // VariantKind. For example, we need to be able to identify the following
135   // entry as a TLSGD entry so we can add the @m relocation:
136   //   .tc .i[TC],i[TL]@m
137   // By default, VK_None is used for the VariantKind.
138   MapVector<std::pair<const MCSymbol *, MCSymbolRefExpr::VariantKind>,
139             MCSymbol *>
140       TOC;
141   const PPCSubtarget *Subtarget = nullptr;
142   StackMaps SM;
143 
144 public:
145   explicit PPCAsmPrinter(TargetMachine &TM,
146                          std::unique_ptr<MCStreamer> Streamer)
147       : AsmPrinter(TM, std::move(Streamer)), SM(*this) {}
148 
149   StringRef getPassName() const override { return "PowerPC Assembly Printer"; }
150 
151   MCSymbol *lookUpOrCreateTOCEntry(const MCSymbol *Sym,
152                                    MCSymbolRefExpr::VariantKind Kind =
153                                        MCSymbolRefExpr::VariantKind::VK_None);
154 
155   bool doInitialization(Module &M) override {
156     if (!TOC.empty())
157       TOC.clear();
158     return AsmPrinter::doInitialization(M);
159   }
160 
161   void emitInstruction(const MachineInstr *MI) override;
162 
163   /// This function is for PrintAsmOperand and PrintAsmMemoryOperand,
164   /// invoked by EmitMSInlineAsmStr and EmitGCCInlineAsmStr only.
165   /// The \p MI would be INLINEASM ONLY.
166   void printOperand(const MachineInstr *MI, unsigned OpNo, raw_ostream &O);
167 
168   void PrintSymbolOperand(const MachineOperand &MO, raw_ostream &O) override;
169   bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
170                        const char *ExtraCode, raw_ostream &O) override;
171   bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
172                              const char *ExtraCode, raw_ostream &O) override;
173 
174   void emitEndOfAsmFile(Module &M) override;
175 
176   void LowerSTACKMAP(StackMaps &SM, const MachineInstr &MI);
177   void LowerPATCHPOINT(StackMaps &SM, const MachineInstr &MI);
178   void EmitTlsCall(const MachineInstr *MI, MCSymbolRefExpr::VariantKind VK);
179   bool runOnMachineFunction(MachineFunction &MF) override {
180     Subtarget = &MF.getSubtarget<PPCSubtarget>();
181     bool Changed = AsmPrinter::runOnMachineFunction(MF);
182     emitXRayTable();
183     return Changed;
184   }
185 };
186 
187 /// PPCLinuxAsmPrinter - PowerPC assembly printer, customized for Linux
188 class PPCLinuxAsmPrinter : public PPCAsmPrinter {
189 public:
190   explicit PPCLinuxAsmPrinter(TargetMachine &TM,
191                               std::unique_ptr<MCStreamer> Streamer)
192       : PPCAsmPrinter(TM, std::move(Streamer)) {}
193 
194   StringRef getPassName() const override {
195     return "Linux PPC Assembly Printer";
196   }
197 
198   void emitGNUAttributes(Module &M);
199 
200   void emitStartOfAsmFile(Module &M) override;
201   void emitEndOfAsmFile(Module &) override;
202 
203   void emitFunctionEntryLabel() override;
204 
205   void emitFunctionBodyStart() override;
206   void emitFunctionBodyEnd() override;
207   void emitInstruction(const MachineInstr *MI) override;
208 };
209 
210 class PPCAIXAsmPrinter : public PPCAsmPrinter {
211 private:
212   /// Symbols lowered from ExternalSymbolSDNodes, we will need to emit extern
213   /// linkage for them in AIX.
214   SmallPtrSet<MCSymbol *, 8> ExtSymSDNodeSymbols;
215 
216   /// A format indicator and unique trailing identifier to form part of the
217   /// sinit/sterm function names.
218   std::string FormatIndicatorAndUniqueModId;
219 
220   // Record a list of GlobalAlias associated with a GlobalObject.
221   // This is used for AIX's extra-label-at-definition aliasing strategy.
222   DenseMap<const GlobalObject *, SmallVector<const GlobalAlias *, 1>>
223       GOAliasMap;
224 
225   uint16_t getNumberOfVRSaved();
226   void emitTracebackTable();
227 
228   SmallVector<const GlobalVariable *, 8> TOCDataGlobalVars;
229 
230   void emitGlobalVariableHelper(const GlobalVariable *);
231 
232 public:
233   PPCAIXAsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer)
234       : PPCAsmPrinter(TM, std::move(Streamer)) {
235     if (MAI->isLittleEndian())
236       report_fatal_error(
237           "cannot create AIX PPC Assembly Printer for a little-endian target");
238   }
239 
240   StringRef getPassName() const override { return "AIX PPC Assembly Printer"; }
241 
242   bool doInitialization(Module &M) override;
243 
244   void emitXXStructorList(const DataLayout &DL, const Constant *List,
245                           bool IsCtor) override;
246 
247   void SetupMachineFunction(MachineFunction &MF) override;
248 
249   void emitGlobalVariable(const GlobalVariable *GV) override;
250 
251   void emitFunctionDescriptor() override;
252 
253   void emitFunctionEntryLabel() override;
254 
255   void emitFunctionBodyEnd() override;
256 
257   void emitEndOfAsmFile(Module &) override;
258 
259   void emitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const override;
260 
261   void emitInstruction(const MachineInstr *MI) override;
262 
263   bool doFinalization(Module &M) override;
264 
265   void emitTTypeReference(const GlobalValue *GV, unsigned Encoding) override;
266 };
267 
268 } // end anonymous namespace
269 
270 void PPCAsmPrinter::PrintSymbolOperand(const MachineOperand &MO,
271                                        raw_ostream &O) {
272   // Computing the address of a global symbol, not calling it.
273   const GlobalValue *GV = MO.getGlobal();
274   getSymbol(GV)->print(O, MAI);
275   printOffset(MO.getOffset(), O);
276 }
277 
278 void PPCAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
279                                  raw_ostream &O) {
280   const DataLayout &DL = getDataLayout();
281   const MachineOperand &MO = MI->getOperand(OpNo);
282 
283   switch (MO.getType()) {
284   case MachineOperand::MO_Register: {
285     // The MI is INLINEASM ONLY and UseVSXReg is always false.
286     const char *RegName = PPCInstPrinter::getRegisterName(MO.getReg());
287 
288     // Linux assembler (Others?) does not take register mnemonics.
289     // FIXME - What about special registers used in mfspr/mtspr?
290     O << PPCRegisterInfo::stripRegisterPrefix(RegName);
291     return;
292   }
293   case MachineOperand::MO_Immediate:
294     O << MO.getImm();
295     return;
296 
297   case MachineOperand::MO_MachineBasicBlock:
298     MO.getMBB()->getSymbol()->print(O, MAI);
299     return;
300   case MachineOperand::MO_ConstantPoolIndex:
301     O << DL.getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
302       << MO.getIndex();
303     return;
304   case MachineOperand::MO_BlockAddress:
305     GetBlockAddressSymbol(MO.getBlockAddress())->print(O, MAI);
306     return;
307   case MachineOperand::MO_GlobalAddress: {
308     PrintSymbolOperand(MO, O);
309     return;
310   }
311 
312   default:
313     O << "<unknown operand type: " << (unsigned)MO.getType() << ">";
314     return;
315   }
316 }
317 
318 /// PrintAsmOperand - Print out an operand for an inline asm expression.
319 ///
320 bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
321                                     const char *ExtraCode, raw_ostream &O) {
322   // Does this asm operand have a single letter operand modifier?
323   if (ExtraCode && ExtraCode[0]) {
324     if (ExtraCode[1] != 0) return true; // Unknown modifier.
325 
326     switch (ExtraCode[0]) {
327     default:
328       // See if this is a generic print operand
329       return AsmPrinter::PrintAsmOperand(MI, OpNo, ExtraCode, O);
330     case 'L': // Write second word of DImode reference.
331       // Verify that this operand has two consecutive registers.
332       if (!MI->getOperand(OpNo).isReg() ||
333           OpNo+1 == MI->getNumOperands() ||
334           !MI->getOperand(OpNo+1).isReg())
335         return true;
336       ++OpNo;   // Return the high-part.
337       break;
338     case 'I':
339       // Write 'i' if an integer constant, otherwise nothing.  Used to print
340       // addi vs add, etc.
341       if (MI->getOperand(OpNo).isImm())
342         O << "i";
343       return false;
344     case 'x':
345       if(!MI->getOperand(OpNo).isReg())
346         return true;
347       // This operand uses VSX numbering.
348       // If the operand is a VMX register, convert it to a VSX register.
349       Register Reg = MI->getOperand(OpNo).getReg();
350       if (PPCInstrInfo::isVRRegister(Reg))
351         Reg = PPC::VSX32 + (Reg - PPC::V0);
352       else if (PPCInstrInfo::isVFRegister(Reg))
353         Reg = PPC::VSX32 + (Reg - PPC::VF0);
354       const char *RegName;
355       RegName = PPCInstPrinter::getRegisterName(Reg);
356       RegName = PPCRegisterInfo::stripRegisterPrefix(RegName);
357       O << RegName;
358       return false;
359     }
360   }
361 
362   printOperand(MI, OpNo, O);
363   return false;
364 }
365 
366 // At the moment, all inline asm memory operands are a single register.
367 // In any case, the output of this routine should always be just one
368 // assembler operand.
369 bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
370                                           const char *ExtraCode,
371                                           raw_ostream &O) {
372   if (ExtraCode && ExtraCode[0]) {
373     if (ExtraCode[1] != 0) return true; // Unknown modifier.
374 
375     switch (ExtraCode[0]) {
376     default: return true;  // Unknown modifier.
377     case 'L': // A memory reference to the upper word of a double word op.
378       O << getDataLayout().getPointerSize() << "(";
379       printOperand(MI, OpNo, O);
380       O << ")";
381       return false;
382     case 'y': // A memory reference for an X-form instruction
383       O << "0, ";
384       printOperand(MI, OpNo, O);
385       return false;
386     case 'I':
387       // Write 'i' if an integer constant, otherwise nothing.  Used to print
388       // addi vs add, etc.
389       if (MI->getOperand(OpNo).isImm())
390         O << "i";
391       return false;
392     case 'U': // Print 'u' for update form.
393     case 'X': // Print 'x' for indexed form.
394       // FIXME: Currently for PowerPC memory operands are always loaded
395       // into a register, so we never get an update or indexed form.
396       // This is bad even for offset forms, since even if we know we
397       // have a value in -16(r1), we will generate a load into r<n>
398       // and then load from 0(r<n>).  Until that issue is fixed,
399       // tolerate 'U' and 'X' but don't output anything.
400       assert(MI->getOperand(OpNo).isReg());
401       return false;
402     }
403   }
404 
405   assert(MI->getOperand(OpNo).isReg());
406   O << "0(";
407   printOperand(MI, OpNo, O);
408   O << ")";
409   return false;
410 }
411 
412 /// lookUpOrCreateTOCEntry -- Given a symbol, look up whether a TOC entry
413 /// exists for it.  If not, create one.  Then return a symbol that references
414 /// the TOC entry.
415 MCSymbol *
416 PPCAsmPrinter::lookUpOrCreateTOCEntry(const MCSymbol *Sym,
417                                       MCSymbolRefExpr::VariantKind Kind) {
418   MCSymbol *&TOCEntry = TOC[{Sym, Kind}];
419   if (!TOCEntry)
420     TOCEntry = createTempSymbol("C");
421   return TOCEntry;
422 }
423 
424 void PPCAsmPrinter::emitEndOfAsmFile(Module &M) {
425   emitStackMaps(SM);
426 }
427 
428 void PPCAsmPrinter::LowerSTACKMAP(StackMaps &SM, const MachineInstr &MI) {
429   unsigned NumNOPBytes = MI.getOperand(1).getImm();
430 
431   auto &Ctx = OutStreamer->getContext();
432   MCSymbol *MILabel = Ctx.createTempSymbol();
433   OutStreamer->emitLabel(MILabel);
434 
435   SM.recordStackMap(*MILabel, MI);
436   assert(NumNOPBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
437 
438   // Scan ahead to trim the shadow.
439   const MachineBasicBlock &MBB = *MI.getParent();
440   MachineBasicBlock::const_iterator MII(MI);
441   ++MII;
442   while (NumNOPBytes > 0) {
443     if (MII == MBB.end() || MII->isCall() ||
444         MII->getOpcode() == PPC::DBG_VALUE ||
445         MII->getOpcode() == TargetOpcode::PATCHPOINT ||
446         MII->getOpcode() == TargetOpcode::STACKMAP)
447       break;
448     ++MII;
449     NumNOPBytes -= 4;
450   }
451 
452   // Emit nops.
453   for (unsigned i = 0; i < NumNOPBytes; i += 4)
454     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
455 }
456 
457 // Lower a patchpoint of the form:
458 // [<def>], <id>, <numBytes>, <target>, <numArgs>
459 void PPCAsmPrinter::LowerPATCHPOINT(StackMaps &SM, const MachineInstr &MI) {
460   auto &Ctx = OutStreamer->getContext();
461   MCSymbol *MILabel = Ctx.createTempSymbol();
462   OutStreamer->emitLabel(MILabel);
463 
464   SM.recordPatchPoint(*MILabel, MI);
465   PatchPointOpers Opers(&MI);
466 
467   unsigned EncodedBytes = 0;
468   const MachineOperand &CalleeMO = Opers.getCallTarget();
469 
470   if (CalleeMO.isImm()) {
471     int64_t CallTarget = CalleeMO.getImm();
472     if (CallTarget) {
473       assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget &&
474              "High 16 bits of call target should be zero.");
475       Register ScratchReg = MI.getOperand(Opers.getNextScratchIdx()).getReg();
476       EncodedBytes = 0;
477       // Materialize the jump address:
478       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LI8)
479                                       .addReg(ScratchReg)
480                                       .addImm((CallTarget >> 32) & 0xFFFF));
481       ++EncodedBytes;
482       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::RLDIC)
483                                       .addReg(ScratchReg)
484                                       .addReg(ScratchReg)
485                                       .addImm(32).addImm(16));
486       ++EncodedBytes;
487       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ORIS8)
488                                       .addReg(ScratchReg)
489                                       .addReg(ScratchReg)
490                                       .addImm((CallTarget >> 16) & 0xFFFF));
491       ++EncodedBytes;
492       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ORI8)
493                                       .addReg(ScratchReg)
494                                       .addReg(ScratchReg)
495                                       .addImm(CallTarget & 0xFFFF));
496 
497       // Save the current TOC pointer before the remote call.
498       int TOCSaveOffset = Subtarget->getFrameLowering()->getTOCSaveOffset();
499       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::STD)
500                                       .addReg(PPC::X2)
501                                       .addImm(TOCSaveOffset)
502                                       .addReg(PPC::X1));
503       ++EncodedBytes;
504 
505       // If we're on ELFv1, then we need to load the actual function pointer
506       // from the function descriptor.
507       if (!Subtarget->isELFv2ABI()) {
508         // Load the new TOC pointer and the function address, but not r11
509         // (needing this is rare, and loading it here would prevent passing it
510         // via a 'nest' parameter.
511         EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
512                                         .addReg(PPC::X2)
513                                         .addImm(8)
514                                         .addReg(ScratchReg));
515         ++EncodedBytes;
516         EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
517                                         .addReg(ScratchReg)
518                                         .addImm(0)
519                                         .addReg(ScratchReg));
520         ++EncodedBytes;
521       }
522 
523       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTCTR8)
524                                       .addReg(ScratchReg));
525       ++EncodedBytes;
526       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BCTRL8));
527       ++EncodedBytes;
528 
529       // Restore the TOC pointer after the call.
530       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
531                                       .addReg(PPC::X2)
532                                       .addImm(TOCSaveOffset)
533                                       .addReg(PPC::X1));
534       ++EncodedBytes;
535     }
536   } else if (CalleeMO.isGlobal()) {
537     const GlobalValue *GValue = CalleeMO.getGlobal();
538     MCSymbol *MOSymbol = getSymbol(GValue);
539     const MCExpr *SymVar = MCSymbolRefExpr::create(MOSymbol, OutContext);
540 
541     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL8_NOP)
542                                     .addExpr(SymVar));
543     EncodedBytes += 2;
544   }
545 
546   // Each instruction is 4 bytes.
547   EncodedBytes *= 4;
548 
549   // Emit padding.
550   unsigned NumBytes = Opers.getNumPatchBytes();
551   assert(NumBytes >= EncodedBytes &&
552          "Patchpoint can't request size less than the length of a call.");
553   assert((NumBytes - EncodedBytes) % 4 == 0 &&
554          "Invalid number of NOP bytes requested!");
555   for (unsigned i = EncodedBytes; i < NumBytes; i += 4)
556     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
557 }
558 
559 /// This helper function creates the TlsGetAddr MCSymbol for AIX. We will
560 /// create the csect and use the qual-name symbol instead of creating just the
561 /// external symbol.
562 static MCSymbol *createMCSymbolForTlsGetAddr(MCContext &Ctx) {
563   return Ctx
564       .getXCOFFSection(".__tls_get_addr", SectionKind::getText(),
565                        XCOFF::CsectProperties(XCOFF::XMC_PR, XCOFF::XTY_ER))
566       ->getQualNameSymbol();
567 }
568 
569 /// EmitTlsCall -- Given a GETtls[ld]ADDR[32] instruction, print a
570 /// call to __tls_get_addr to the current output stream.
571 void PPCAsmPrinter::EmitTlsCall(const MachineInstr *MI,
572                                 MCSymbolRefExpr::VariantKind VK) {
573   MCSymbolRefExpr::VariantKind Kind = MCSymbolRefExpr::VK_None;
574   unsigned Opcode = PPC::BL8_NOP_TLS;
575 
576   assert(MI->getNumOperands() >= 3 && "Expecting at least 3 operands from MI");
577   if (MI->getOperand(2).getTargetFlags() == PPCII::MO_GOT_TLSGD_PCREL_FLAG ||
578       MI->getOperand(2).getTargetFlags() == PPCII::MO_GOT_TLSLD_PCREL_FLAG) {
579     Kind = MCSymbolRefExpr::VK_PPC_NOTOC;
580     Opcode = PPC::BL8_NOTOC_TLS;
581   }
582   const Module *M = MF->getFunction().getParent();
583 
584   assert(MI->getOperand(0).isReg() &&
585          ((Subtarget->isPPC64() && MI->getOperand(0).getReg() == PPC::X3) ||
586           (!Subtarget->isPPC64() && MI->getOperand(0).getReg() == PPC::R3)) &&
587          "GETtls[ld]ADDR[32] must define GPR3");
588   assert(MI->getOperand(1).isReg() &&
589          ((Subtarget->isPPC64() && MI->getOperand(1).getReg() == PPC::X3) ||
590           (!Subtarget->isPPC64() && MI->getOperand(1).getReg() == PPC::R3)) &&
591          "GETtls[ld]ADDR[32] must read GPR3");
592 
593   if (Subtarget->isAIXABI()) {
594     // On AIX, the variable offset should already be in R4 and the region handle
595     // should already be in R3.
596     // For TLSGD, which currently is the only supported access model, we only
597     // need to generate an absolute branch to .__tls_get_addr.
598     Register VarOffsetReg = Subtarget->isPPC64() ? PPC::X4 : PPC::R4;
599     (void)VarOffsetReg;
600     assert(MI->getOperand(2).isReg() &&
601            MI->getOperand(2).getReg() == VarOffsetReg &&
602            "GETtls[ld]ADDR[32] must read GPR4");
603     MCSymbol *TlsGetAddr = createMCSymbolForTlsGetAddr(OutContext);
604     const MCExpr *TlsRef = MCSymbolRefExpr::create(
605         TlsGetAddr, MCSymbolRefExpr::VK_None, OutContext);
606     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BLA).addExpr(TlsRef));
607     return;
608   }
609 
610   MCSymbol *TlsGetAddr = OutContext.getOrCreateSymbol("__tls_get_addr");
611 
612   if (Subtarget->is32BitELFABI() && isPositionIndependent())
613     Kind = MCSymbolRefExpr::VK_PLT;
614 
615   const MCExpr *TlsRef =
616     MCSymbolRefExpr::create(TlsGetAddr, Kind, OutContext);
617 
618   // Add 32768 offset to the symbol so we follow up the latest GOT/PLT ABI.
619   if (Kind == MCSymbolRefExpr::VK_PLT && Subtarget->isSecurePlt() &&
620       M->getPICLevel() == PICLevel::BigPIC)
621     TlsRef = MCBinaryExpr::createAdd(
622         TlsRef, MCConstantExpr::create(32768, OutContext), OutContext);
623   const MachineOperand &MO = MI->getOperand(2);
624   const GlobalValue *GValue = MO.getGlobal();
625   MCSymbol *MOSymbol = getSymbol(GValue);
626   const MCExpr *SymVar = MCSymbolRefExpr::create(MOSymbol, VK, OutContext);
627   EmitToStreamer(*OutStreamer,
628                  MCInstBuilder(Subtarget->isPPC64() ? Opcode
629                                                     : (unsigned)PPC::BL_TLS)
630                      .addExpr(TlsRef)
631                      .addExpr(SymVar));
632 }
633 
634 /// Map a machine operand for a TOC pseudo-machine instruction to its
635 /// corresponding MCSymbol.
636 static MCSymbol *getMCSymbolForTOCPseudoMO(const MachineOperand &MO,
637                                            AsmPrinter &AP) {
638   switch (MO.getType()) {
639   case MachineOperand::MO_GlobalAddress:
640     return AP.getSymbol(MO.getGlobal());
641   case MachineOperand::MO_ConstantPoolIndex:
642     return AP.GetCPISymbol(MO.getIndex());
643   case MachineOperand::MO_JumpTableIndex:
644     return AP.GetJTISymbol(MO.getIndex());
645   case MachineOperand::MO_BlockAddress:
646     return AP.GetBlockAddressSymbol(MO.getBlockAddress());
647   default:
648     llvm_unreachable("Unexpected operand type to get symbol.");
649   }
650 }
651 
652 /// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
653 /// the current output stream.
654 ///
655 void PPCAsmPrinter::emitInstruction(const MachineInstr *MI) {
656   MCInst TmpInst;
657   const bool IsPPC64 = Subtarget->isPPC64();
658   const bool IsAIX = Subtarget->isAIXABI();
659   const Module *M = MF->getFunction().getParent();
660   PICLevel::Level PL = M->getPICLevel();
661 
662 #ifndef NDEBUG
663   // Validate that SPE and FPU are mutually exclusive in codegen
664   if (!MI->isInlineAsm()) {
665     for (const MachineOperand &MO: MI->operands()) {
666       if (MO.isReg()) {
667         Register Reg = MO.getReg();
668         if (Subtarget->hasSPE()) {
669           if (PPC::F4RCRegClass.contains(Reg) ||
670               PPC::F8RCRegClass.contains(Reg) ||
671               PPC::VFRCRegClass.contains(Reg) ||
672               PPC::VRRCRegClass.contains(Reg) ||
673               PPC::VSFRCRegClass.contains(Reg) ||
674               PPC::VSSRCRegClass.contains(Reg)
675               )
676             llvm_unreachable("SPE targets cannot have FPRegs!");
677         } else {
678           if (PPC::SPERCRegClass.contains(Reg))
679             llvm_unreachable("SPE register found in FPU-targeted code!");
680         }
681       }
682     }
683   }
684 #endif
685 
686   auto getTOCRelocAdjustedExprForXCOFF = [this](const MCExpr *Expr,
687                                                 ptrdiff_t OriginalOffset) {
688     // Apply an offset to the TOC-based expression such that the adjusted
689     // notional offset from the TOC base (to be encoded into the instruction's D
690     // or DS field) is the signed 16-bit truncation of the original notional
691     // offset from the TOC base.
692     // This is consistent with the treatment used both by XL C/C++ and
693     // by AIX ld -r.
694     ptrdiff_t Adjustment =
695         OriginalOffset - llvm::SignExtend32<16>(OriginalOffset);
696     return MCBinaryExpr::createAdd(
697         Expr, MCConstantExpr::create(-Adjustment, OutContext), OutContext);
698   };
699 
700   auto getTOCEntryLoadingExprForXCOFF =
701       [IsPPC64, getTOCRelocAdjustedExprForXCOFF,
702        this](const MCSymbol *MOSymbol, const MCExpr *Expr,
703              MCSymbolRefExpr::VariantKind VK =
704                  MCSymbolRefExpr::VariantKind::VK_None) -> const MCExpr * {
705     const unsigned EntryByteSize = IsPPC64 ? 8 : 4;
706     const auto TOCEntryIter = TOC.find({MOSymbol, VK});
707     assert(TOCEntryIter != TOC.end() &&
708            "Could not find the TOC entry for this symbol.");
709     const ptrdiff_t EntryDistanceFromTOCBase =
710         (TOCEntryIter - TOC.begin()) * EntryByteSize;
711     constexpr int16_t PositiveTOCRange = INT16_MAX;
712 
713     if (EntryDistanceFromTOCBase > PositiveTOCRange)
714       return getTOCRelocAdjustedExprForXCOFF(Expr, EntryDistanceFromTOCBase);
715 
716     return Expr;
717   };
718   auto GetVKForMO = [&](const MachineOperand &MO) {
719     // For GD TLS access on AIX, we have two TOC entries for the symbol (one for
720     // the variable offset and the other for the region handle). They are
721     // differentiated by MO_TLSGD_FLAG and MO_TLSGDM_FLAG.
722     if (MO.getTargetFlags() & PPCII::MO_TLSGDM_FLAG)
723       return MCSymbolRefExpr::VariantKind::VK_PPC_AIX_TLSGDM;
724     if (MO.getTargetFlags() & PPCII::MO_TLSGD_FLAG)
725       return MCSymbolRefExpr::VariantKind::VK_PPC_AIX_TLSGD;
726     return MCSymbolRefExpr::VariantKind::VK_None;
727   };
728 
729   // Lower multi-instruction pseudo operations.
730   switch (MI->getOpcode()) {
731   default: break;
732   case TargetOpcode::DBG_VALUE:
733     llvm_unreachable("Should be handled target independently");
734   case TargetOpcode::STACKMAP:
735     return LowerSTACKMAP(SM, *MI);
736   case TargetOpcode::PATCHPOINT:
737     return LowerPATCHPOINT(SM, *MI);
738 
739   case PPC::MoveGOTtoLR: {
740     // Transform %lr = MoveGOTtoLR
741     // Into this: bl _GLOBAL_OFFSET_TABLE_@local-4
742     // _GLOBAL_OFFSET_TABLE_@local-4 (instruction preceding
743     // _GLOBAL_OFFSET_TABLE_) has exactly one instruction:
744     //      blrl
745     // This will return the pointer to _GLOBAL_OFFSET_TABLE_@local
746     MCSymbol *GOTSymbol =
747       OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
748     const MCExpr *OffsExpr =
749       MCBinaryExpr::createSub(MCSymbolRefExpr::create(GOTSymbol,
750                                                       MCSymbolRefExpr::VK_PPC_LOCAL,
751                                                       OutContext),
752                               MCConstantExpr::create(4, OutContext),
753                               OutContext);
754 
755     // Emit the 'bl'.
756     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL).addExpr(OffsExpr));
757     return;
758   }
759   case PPC::MovePCtoLR:
760   case PPC::MovePCtoLR8: {
761     // Transform %lr = MovePCtoLR
762     // Into this, where the label is the PIC base:
763     //     bl L1$pb
764     // L1$pb:
765     MCSymbol *PICBase = MF->getPICBaseSymbol();
766 
767     // Emit the 'bl'.
768     EmitToStreamer(*OutStreamer,
769                    MCInstBuilder(PPC::BL)
770                        // FIXME: We would like an efficient form for this, so we
771                        // don't have to do a lot of extra uniquing.
772                        .addExpr(MCSymbolRefExpr::create(PICBase, OutContext)));
773 
774     // Emit the label.
775     OutStreamer->emitLabel(PICBase);
776     return;
777   }
778   case PPC::UpdateGBR: {
779     // Transform %rd = UpdateGBR(%rt, %ri)
780     // Into: lwz %rt, .L0$poff - .L0$pb(%ri)
781     //       add %rd, %rt, %ri
782     // or into (if secure plt mode is on):
783     //       addis r30, r30, {.LTOC,_GLOBAL_OFFSET_TABLE} - .L0$pb@ha
784     //       addi r30, r30, {.LTOC,_GLOBAL_OFFSET_TABLE} - .L0$pb@l
785     // Get the offset from the GOT Base Register to the GOT
786     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
787     if (Subtarget->isSecurePlt() && isPositionIndependent() ) {
788       unsigned PICR = TmpInst.getOperand(0).getReg();
789       MCSymbol *BaseSymbol = OutContext.getOrCreateSymbol(
790           M->getPICLevel() == PICLevel::SmallPIC ? "_GLOBAL_OFFSET_TABLE_"
791                                                  : ".LTOC");
792       const MCExpr *PB =
793           MCSymbolRefExpr::create(MF->getPICBaseSymbol(), OutContext);
794 
795       const MCExpr *DeltaExpr = MCBinaryExpr::createSub(
796           MCSymbolRefExpr::create(BaseSymbol, OutContext), PB, OutContext);
797 
798       const MCExpr *DeltaHi = PPCMCExpr::createHa(DeltaExpr, OutContext);
799       EmitToStreamer(
800           *OutStreamer,
801           MCInstBuilder(PPC::ADDIS).addReg(PICR).addReg(PICR).addExpr(DeltaHi));
802 
803       const MCExpr *DeltaLo = PPCMCExpr::createLo(DeltaExpr, OutContext);
804       EmitToStreamer(
805           *OutStreamer,
806           MCInstBuilder(PPC::ADDI).addReg(PICR).addReg(PICR).addExpr(DeltaLo));
807       return;
808     } else {
809       MCSymbol *PICOffset =
810         MF->getInfo<PPCFunctionInfo>()->getPICOffsetSymbol(*MF);
811       TmpInst.setOpcode(PPC::LWZ);
812       const MCExpr *Exp =
813         MCSymbolRefExpr::create(PICOffset, MCSymbolRefExpr::VK_None, OutContext);
814       const MCExpr *PB =
815         MCSymbolRefExpr::create(MF->getPICBaseSymbol(),
816                                 MCSymbolRefExpr::VK_None,
817                                 OutContext);
818       const MCOperand TR = TmpInst.getOperand(1);
819       const MCOperand PICR = TmpInst.getOperand(0);
820 
821       // Step 1: lwz %rt, .L$poff - .L$pb(%ri)
822       TmpInst.getOperand(1) =
823           MCOperand::createExpr(MCBinaryExpr::createSub(Exp, PB, OutContext));
824       TmpInst.getOperand(0) = TR;
825       TmpInst.getOperand(2) = PICR;
826       EmitToStreamer(*OutStreamer, TmpInst);
827 
828       TmpInst.setOpcode(PPC::ADD4);
829       TmpInst.getOperand(0) = PICR;
830       TmpInst.getOperand(1) = TR;
831       TmpInst.getOperand(2) = PICR;
832       EmitToStreamer(*OutStreamer, TmpInst);
833       return;
834     }
835   }
836   case PPC::LWZtoc: {
837     // Transform %rN = LWZtoc @op1, %r2
838     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
839 
840     // Change the opcode to LWZ.
841     TmpInst.setOpcode(PPC::LWZ);
842 
843     const MachineOperand &MO = MI->getOperand(1);
844     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress()) &&
845            "Invalid operand for LWZtoc.");
846 
847     // Map the operand to its corresponding MCSymbol.
848     const MCSymbol *const MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
849 
850     // Create a reference to the GOT entry for the symbol. The GOT entry will be
851     // synthesized later.
852     if (PL == PICLevel::SmallPIC && !IsAIX) {
853       const MCExpr *Exp =
854         MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_GOT,
855                                 OutContext);
856       TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
857       EmitToStreamer(*OutStreamer, TmpInst);
858       return;
859     }
860 
861     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
862 
863     // Otherwise, use the TOC. 'TOCEntry' is a label used to reference the
864     // storage allocated in the TOC which contains the address of
865     // 'MOSymbol'. Said TOC entry will be synthesized later.
866     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol, VK);
867     const MCExpr *Exp =
868         MCSymbolRefExpr::create(TOCEntry, MCSymbolRefExpr::VK_None, OutContext);
869 
870     // AIX uses the label directly as the lwz displacement operand for
871     // references into the toc section. The displacement value will be generated
872     // relative to the toc-base.
873     if (IsAIX) {
874       assert(
875           TM.getCodeModel() == CodeModel::Small &&
876           "This pseudo should only be selected for 32-bit small code model.");
877       Exp = getTOCEntryLoadingExprForXCOFF(MOSymbol, Exp, VK);
878       TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
879 
880       // Print MO for better readability
881       if (isVerbose())
882         OutStreamer->GetCommentOS() << MO << '\n';
883       EmitToStreamer(*OutStreamer, TmpInst);
884       return;
885     }
886 
887     // Create an explicit subtract expression between the local symbol and
888     // '.LTOC' to manifest the toc-relative offset.
889     const MCExpr *PB = MCSymbolRefExpr::create(
890         OutContext.getOrCreateSymbol(Twine(".LTOC")), OutContext);
891     Exp = MCBinaryExpr::createSub(Exp, PB, OutContext);
892     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
893     EmitToStreamer(*OutStreamer, TmpInst);
894     return;
895   }
896   case PPC::ADDItoc:
897   case PPC::ADDItoc8: {
898     assert(IsAIX && TM.getCodeModel() == CodeModel::Small &&
899            "PseudoOp only valid for small code model AIX");
900 
901     // Transform %rN = ADDItoc/8 @op1, %r2.
902     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
903 
904     // Change the opcode to load address.
905     TmpInst.setOpcode((!IsPPC64) ? (PPC::LA) : (PPC::LA8));
906 
907     const MachineOperand &MO = MI->getOperand(1);
908     assert(MO.isGlobal() && "Invalid operand for ADDItoc[8].");
909 
910     // Map the operand to its corresponding MCSymbol.
911     const MCSymbol *const MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
912 
913     const MCExpr *Exp =
914         MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_None, OutContext);
915 
916     TmpInst.getOperand(1) = TmpInst.getOperand(2);
917     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
918     EmitToStreamer(*OutStreamer, TmpInst);
919     return;
920   }
921   case PPC::LDtocJTI:
922   case PPC::LDtocCPT:
923   case PPC::LDtocBA:
924   case PPC::LDtoc: {
925     // Transform %x3 = LDtoc @min1, %x2
926     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
927 
928     // Change the opcode to LD.
929     TmpInst.setOpcode(PPC::LD);
930 
931     const MachineOperand &MO = MI->getOperand(1);
932     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress()) &&
933            "Invalid operand!");
934 
935     // Map the operand to its corresponding MCSymbol.
936     const MCSymbol *const MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
937 
938     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
939 
940     // Map the machine operand to its corresponding MCSymbol, then map the
941     // global address operand to be a reference to the TOC entry we will
942     // synthesize later.
943     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol, VK);
944 
945     MCSymbolRefExpr::VariantKind VKExpr =
946         IsAIX ? MCSymbolRefExpr::VK_None : MCSymbolRefExpr::VK_PPC_TOC;
947     const MCExpr *Exp = MCSymbolRefExpr::create(TOCEntry, VKExpr, OutContext);
948     TmpInst.getOperand(1) = MCOperand::createExpr(
949         IsAIX ? getTOCEntryLoadingExprForXCOFF(MOSymbol, Exp, VK) : Exp);
950 
951     // Print MO for better readability
952     if (isVerbose() && IsAIX)
953       OutStreamer->GetCommentOS() << MO << '\n';
954     EmitToStreamer(*OutStreamer, TmpInst);
955     return;
956   }
957   case PPC::ADDIStocHA: {
958     assert((IsAIX && !IsPPC64 && TM.getCodeModel() == CodeModel::Large) &&
959            "This pseudo should only be selected for 32-bit large code model on"
960            " AIX.");
961 
962     // Transform %rd = ADDIStocHA %rA, @sym(%r2)
963     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
964 
965     // Change the opcode to ADDIS.
966     TmpInst.setOpcode(PPC::ADDIS);
967 
968     const MachineOperand &MO = MI->getOperand(2);
969     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress()) &&
970            "Invalid operand for ADDIStocHA.");
971 
972     // Map the machine operand to its corresponding MCSymbol.
973     MCSymbol *MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
974 
975     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
976 
977     // Always use TOC on AIX. Map the global address operand to be a reference
978     // to the TOC entry we will synthesize later. 'TOCEntry' is a label used to
979     // reference the storage allocated in the TOC which contains the address of
980     // 'MOSymbol'.
981     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol, VK);
982     const MCExpr *Exp = MCSymbolRefExpr::create(TOCEntry,
983                                                 MCSymbolRefExpr::VK_PPC_U,
984                                                 OutContext);
985     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
986     EmitToStreamer(*OutStreamer, TmpInst);
987     return;
988   }
989   case PPC::LWZtocL: {
990     assert(IsAIX && !IsPPC64 && TM.getCodeModel() == CodeModel::Large &&
991            "This pseudo should only be selected for 32-bit large code model on"
992            " AIX.");
993 
994     // Transform %rd = LWZtocL @sym, %rs.
995     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
996 
997     // Change the opcode to lwz.
998     TmpInst.setOpcode(PPC::LWZ);
999 
1000     const MachineOperand &MO = MI->getOperand(1);
1001     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress()) &&
1002            "Invalid operand for LWZtocL.");
1003 
1004     // Map the machine operand to its corresponding MCSymbol.
1005     MCSymbol *MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
1006 
1007     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
1008 
1009     // Always use TOC on AIX. Map the global address operand to be a reference
1010     // to the TOC entry we will synthesize later. 'TOCEntry' is a label used to
1011     // reference the storage allocated in the TOC which contains the address of
1012     // 'MOSymbol'.
1013     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol, VK);
1014     const MCExpr *Exp = MCSymbolRefExpr::create(TOCEntry,
1015                                                 MCSymbolRefExpr::VK_PPC_L,
1016                                                 OutContext);
1017     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
1018     EmitToStreamer(*OutStreamer, TmpInst);
1019     return;
1020   }
1021   case PPC::ADDIStocHA8: {
1022     // Transform %xd = ADDIStocHA8 %x2, @sym
1023     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
1024 
1025     // Change the opcode to ADDIS8. If the global address is the address of
1026     // an external symbol, is a jump table address, is a block address, or is a
1027     // constant pool index with large code model enabled, then generate a TOC
1028     // entry and reference that. Otherwise, reference the symbol directly.
1029     TmpInst.setOpcode(PPC::ADDIS8);
1030 
1031     const MachineOperand &MO = MI->getOperand(2);
1032     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isBlockAddress()) &&
1033            "Invalid operand for ADDIStocHA8!");
1034 
1035     const MCSymbol *MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
1036 
1037     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
1038 
1039     const bool GlobalToc =
1040         MO.isGlobal() && Subtarget->isGVIndirectSymbol(MO.getGlobal());
1041     if (GlobalToc || MO.isJTI() || MO.isBlockAddress() ||
1042         (MO.isCPI() && TM.getCodeModel() == CodeModel::Large))
1043       MOSymbol = lookUpOrCreateTOCEntry(MOSymbol, VK);
1044 
1045     VK = IsAIX ? MCSymbolRefExpr::VK_PPC_U : MCSymbolRefExpr::VK_PPC_TOC_HA;
1046 
1047     const MCExpr *Exp =
1048         MCSymbolRefExpr::create(MOSymbol, VK, OutContext);
1049 
1050     if (!MO.isJTI() && MO.getOffset())
1051       Exp = MCBinaryExpr::createAdd(Exp,
1052                                     MCConstantExpr::create(MO.getOffset(),
1053                                                            OutContext),
1054                                     OutContext);
1055 
1056     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
1057     EmitToStreamer(*OutStreamer, TmpInst);
1058     return;
1059   }
1060   case PPC::LDtocL: {
1061     // Transform %xd = LDtocL @sym, %xs
1062     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
1063 
1064     // Change the opcode to LD. If the global address is the address of
1065     // an external symbol, is a jump table address, is a block address, or is
1066     // a constant pool index with large code model enabled, then generate a
1067     // TOC entry and reference that. Otherwise, reference the symbol directly.
1068     TmpInst.setOpcode(PPC::LD);
1069 
1070     const MachineOperand &MO = MI->getOperand(1);
1071     assert((MO.isGlobal() || MO.isCPI() || MO.isJTI() ||
1072             MO.isBlockAddress()) &&
1073            "Invalid operand for LDtocL!");
1074 
1075     LLVM_DEBUG(assert(
1076         (!MO.isGlobal() || Subtarget->isGVIndirectSymbol(MO.getGlobal())) &&
1077         "LDtocL used on symbol that could be accessed directly is "
1078         "invalid. Must match ADDIStocHA8."));
1079 
1080     const MCSymbol *MOSymbol = getMCSymbolForTOCPseudoMO(MO, *this);
1081 
1082     MCSymbolRefExpr::VariantKind VK = GetVKForMO(MO);
1083 
1084     if (!MO.isCPI() || TM.getCodeModel() == CodeModel::Large)
1085       MOSymbol = lookUpOrCreateTOCEntry(MOSymbol, VK);
1086 
1087     VK = IsAIX ? MCSymbolRefExpr::VK_PPC_L : MCSymbolRefExpr::VK_PPC_TOC_LO;
1088     const MCExpr *Exp =
1089         MCSymbolRefExpr::create(MOSymbol, VK, OutContext);
1090     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
1091     EmitToStreamer(*OutStreamer, TmpInst);
1092     return;
1093   }
1094   case PPC::ADDItocL: {
1095     // Transform %xd = ADDItocL %xs, @sym
1096     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
1097 
1098     // Change the opcode to ADDI8. If the global address is external, then
1099     // generate a TOC entry and reference that. Otherwise, reference the
1100     // symbol directly.
1101     TmpInst.setOpcode(PPC::ADDI8);
1102 
1103     const MachineOperand &MO = MI->getOperand(2);
1104     assert((MO.isGlobal() || MO.isCPI()) && "Invalid operand for ADDItocL.");
1105 
1106     LLVM_DEBUG(assert(
1107         !(MO.isGlobal() && Subtarget->isGVIndirectSymbol(MO.getGlobal())) &&
1108         "Interposable definitions must use indirect access."));
1109 
1110     const MCExpr *Exp =
1111         MCSymbolRefExpr::create(getMCSymbolForTOCPseudoMO(MO, *this),
1112                                 MCSymbolRefExpr::VK_PPC_TOC_LO, OutContext);
1113     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
1114     EmitToStreamer(*OutStreamer, TmpInst);
1115     return;
1116   }
1117   case PPC::ADDISgotTprelHA: {
1118     // Transform: %xd = ADDISgotTprelHA %x2, @sym
1119     // Into:      %xd = ADDIS8 %x2, sym@got@tlsgd@ha
1120     assert(IsPPC64 && "Not supported for 32-bit PowerPC");
1121     const MachineOperand &MO = MI->getOperand(2);
1122     const GlobalValue *GValue = MO.getGlobal();
1123     MCSymbol *MOSymbol = getSymbol(GValue);
1124     const MCExpr *SymGotTprel =
1125         MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA,
1126                                 OutContext);
1127     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
1128                                  .addReg(MI->getOperand(0).getReg())
1129                                  .addReg(MI->getOperand(1).getReg())
1130                                  .addExpr(SymGotTprel));
1131     return;
1132   }
1133   case PPC::LDgotTprelL:
1134   case PPC::LDgotTprelL32: {
1135     // Transform %xd = LDgotTprelL @sym, %xs
1136     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
1137 
1138     // Change the opcode to LD.
1139     TmpInst.setOpcode(IsPPC64 ? PPC::LD : PPC::LWZ);
1140     const MachineOperand &MO = MI->getOperand(1);
1141     const GlobalValue *GValue = MO.getGlobal();
1142     MCSymbol *MOSymbol = getSymbol(GValue);
1143     const MCExpr *Exp = MCSymbolRefExpr::create(
1144         MOSymbol, IsPPC64 ? MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO
1145                           : MCSymbolRefExpr::VK_PPC_GOT_TPREL,
1146         OutContext);
1147     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
1148     EmitToStreamer(*OutStreamer, TmpInst);
1149     return;
1150   }
1151 
1152   case PPC::PPC32PICGOT: {
1153     MCSymbol *GOTSymbol = OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
1154     MCSymbol *GOTRef = OutContext.createTempSymbol();
1155     MCSymbol *NextInstr = OutContext.createTempSymbol();
1156 
1157     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::BL)
1158       // FIXME: We would like an efficient form for this, so we don't have to do
1159       // a lot of extra uniquing.
1160       .addExpr(MCSymbolRefExpr::create(NextInstr, OutContext)));
1161     const MCExpr *OffsExpr =
1162       MCBinaryExpr::createSub(MCSymbolRefExpr::create(GOTSymbol, OutContext),
1163                                 MCSymbolRefExpr::create(GOTRef, OutContext),
1164         OutContext);
1165     OutStreamer->emitLabel(GOTRef);
1166     OutStreamer->emitValue(OffsExpr, 4);
1167     OutStreamer->emitLabel(NextInstr);
1168     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR)
1169                                  .addReg(MI->getOperand(0).getReg()));
1170     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LWZ)
1171                                  .addReg(MI->getOperand(1).getReg())
1172                                  .addImm(0)
1173                                  .addReg(MI->getOperand(0).getReg()));
1174     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADD4)
1175                                  .addReg(MI->getOperand(0).getReg())
1176                                  .addReg(MI->getOperand(1).getReg())
1177                                  .addReg(MI->getOperand(0).getReg()));
1178     return;
1179   }
1180   case PPC::PPC32GOT: {
1181     MCSymbol *GOTSymbol =
1182         OutContext.getOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
1183     const MCExpr *SymGotTlsL = MCSymbolRefExpr::create(
1184         GOTSymbol, MCSymbolRefExpr::VK_PPC_LO, OutContext);
1185     const MCExpr *SymGotTlsHA = MCSymbolRefExpr::create(
1186         GOTSymbol, MCSymbolRefExpr::VK_PPC_HA, OutContext);
1187     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LI)
1188                                  .addReg(MI->getOperand(0).getReg())
1189                                  .addExpr(SymGotTlsL));
1190     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS)
1191                                  .addReg(MI->getOperand(0).getReg())
1192                                  .addReg(MI->getOperand(0).getReg())
1193                                  .addExpr(SymGotTlsHA));
1194     return;
1195   }
1196   case PPC::ADDIStlsgdHA: {
1197     // Transform: %xd = ADDIStlsgdHA %x2, @sym
1198     // Into:      %xd = ADDIS8 %x2, sym@got@tlsgd@ha
1199     assert(IsPPC64 && "Not supported for 32-bit PowerPC");
1200     const MachineOperand &MO = MI->getOperand(2);
1201     const GlobalValue *GValue = MO.getGlobal();
1202     MCSymbol *MOSymbol = getSymbol(GValue);
1203     const MCExpr *SymGotTlsGD =
1204       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA,
1205                               OutContext);
1206     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
1207                                  .addReg(MI->getOperand(0).getReg())
1208                                  .addReg(MI->getOperand(1).getReg())
1209                                  .addExpr(SymGotTlsGD));
1210     return;
1211   }
1212   case PPC::ADDItlsgdL:
1213     // Transform: %xd = ADDItlsgdL %xs, @sym
1214     // Into:      %xd = ADDI8 %xs, sym@got@tlsgd@l
1215   case PPC::ADDItlsgdL32: {
1216     // Transform: %rd = ADDItlsgdL32 %rs, @sym
1217     // Into:      %rd = ADDI %rs, sym@got@tlsgd
1218     const MachineOperand &MO = MI->getOperand(2);
1219     const GlobalValue *GValue = MO.getGlobal();
1220     MCSymbol *MOSymbol = getSymbol(GValue);
1221     const MCExpr *SymGotTlsGD = MCSymbolRefExpr::create(
1222         MOSymbol, IsPPC64 ? MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO
1223                           : MCSymbolRefExpr::VK_PPC_GOT_TLSGD,
1224         OutContext);
1225     EmitToStreamer(*OutStreamer,
1226                    MCInstBuilder(IsPPC64 ? PPC::ADDI8 : PPC::ADDI)
1227                    .addReg(MI->getOperand(0).getReg())
1228                    .addReg(MI->getOperand(1).getReg())
1229                    .addExpr(SymGotTlsGD));
1230     return;
1231   }
1232   case PPC::GETtlsADDR:
1233     // Transform: %x3 = GETtlsADDR %x3, @sym
1234     // Into: BL8_NOP_TLS __tls_get_addr(sym at tlsgd)
1235   case PPC::GETtlsADDRPCREL:
1236   case PPC::GETtlsADDR32AIX:
1237   case PPC::GETtlsADDR64AIX:
1238     // Transform: %r3 = GETtlsADDRNNAIX %r3, %r4 (for NN == 32/64).
1239     // Into: BLA .__tls_get_addr()
1240     // Unlike on Linux, there is no symbol or relocation needed for this call.
1241   case PPC::GETtlsADDR32: {
1242     // Transform: %r3 = GETtlsADDR32 %r3, @sym
1243     // Into: BL_TLS __tls_get_addr(sym at tlsgd)@PLT
1244     EmitTlsCall(MI, MCSymbolRefExpr::VK_PPC_TLSGD);
1245     return;
1246   }
1247   case PPC::ADDIStlsldHA: {
1248     // Transform: %xd = ADDIStlsldHA %x2, @sym
1249     // Into:      %xd = ADDIS8 %x2, sym@got@tlsld@ha
1250     assert(IsPPC64 && "Not supported for 32-bit PowerPC");
1251     const MachineOperand &MO = MI->getOperand(2);
1252     const GlobalValue *GValue = MO.getGlobal();
1253     MCSymbol *MOSymbol = getSymbol(GValue);
1254     const MCExpr *SymGotTlsLD =
1255       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA,
1256                               OutContext);
1257     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS8)
1258                                  .addReg(MI->getOperand(0).getReg())
1259                                  .addReg(MI->getOperand(1).getReg())
1260                                  .addExpr(SymGotTlsLD));
1261     return;
1262   }
1263   case PPC::ADDItlsldL:
1264     // Transform: %xd = ADDItlsldL %xs, @sym
1265     // Into:      %xd = ADDI8 %xs, sym@got@tlsld@l
1266   case PPC::ADDItlsldL32: {
1267     // Transform: %rd = ADDItlsldL32 %rs, @sym
1268     // Into:      %rd = ADDI %rs, sym@got@tlsld
1269     const MachineOperand &MO = MI->getOperand(2);
1270     const GlobalValue *GValue = MO.getGlobal();
1271     MCSymbol *MOSymbol = getSymbol(GValue);
1272     const MCExpr *SymGotTlsLD = MCSymbolRefExpr::create(
1273         MOSymbol, IsPPC64 ? MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO
1274                           : MCSymbolRefExpr::VK_PPC_GOT_TLSLD,
1275         OutContext);
1276     EmitToStreamer(*OutStreamer,
1277                    MCInstBuilder(IsPPC64 ? PPC::ADDI8 : PPC::ADDI)
1278                        .addReg(MI->getOperand(0).getReg())
1279                        .addReg(MI->getOperand(1).getReg())
1280                        .addExpr(SymGotTlsLD));
1281     return;
1282   }
1283   case PPC::GETtlsldADDR:
1284     // Transform: %x3 = GETtlsldADDR %x3, @sym
1285     // Into: BL8_NOP_TLS __tls_get_addr(sym at tlsld)
1286   case PPC::GETtlsldADDRPCREL:
1287   case PPC::GETtlsldADDR32: {
1288     // Transform: %r3 = GETtlsldADDR32 %r3, @sym
1289     // Into: BL_TLS __tls_get_addr(sym at tlsld)@PLT
1290     EmitTlsCall(MI, MCSymbolRefExpr::VK_PPC_TLSLD);
1291     return;
1292   }
1293   case PPC::ADDISdtprelHA:
1294     // Transform: %xd = ADDISdtprelHA %xs, @sym
1295     // Into:      %xd = ADDIS8 %xs, sym@dtprel@ha
1296   case PPC::ADDISdtprelHA32: {
1297     // Transform: %rd = ADDISdtprelHA32 %rs, @sym
1298     // Into:      %rd = ADDIS %rs, sym@dtprel@ha
1299     const MachineOperand &MO = MI->getOperand(2);
1300     const GlobalValue *GValue = MO.getGlobal();
1301     MCSymbol *MOSymbol = getSymbol(GValue);
1302     const MCExpr *SymDtprel =
1303       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_HA,
1304                               OutContext);
1305     EmitToStreamer(
1306         *OutStreamer,
1307         MCInstBuilder(IsPPC64 ? PPC::ADDIS8 : PPC::ADDIS)
1308             .addReg(MI->getOperand(0).getReg())
1309             .addReg(MI->getOperand(1).getReg())
1310             .addExpr(SymDtprel));
1311     return;
1312   }
1313   case PPC::PADDIdtprel: {
1314     // Transform: %rd = PADDIdtprel %rs, @sym
1315     // Into:      %rd = PADDI8 %rs, sym@dtprel
1316     const MachineOperand &MO = MI->getOperand(2);
1317     const GlobalValue *GValue = MO.getGlobal();
1318     MCSymbol *MOSymbol = getSymbol(GValue);
1319     const MCExpr *SymDtprel = MCSymbolRefExpr::create(
1320         MOSymbol, MCSymbolRefExpr::VK_DTPREL, OutContext);
1321     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::PADDI8)
1322                                      .addReg(MI->getOperand(0).getReg())
1323                                      .addReg(MI->getOperand(1).getReg())
1324                                      .addExpr(SymDtprel));
1325     return;
1326   }
1327 
1328   case PPC::ADDIdtprelL:
1329     // Transform: %xd = ADDIdtprelL %xs, @sym
1330     // Into:      %xd = ADDI8 %xs, sym@dtprel@l
1331   case PPC::ADDIdtprelL32: {
1332     // Transform: %rd = ADDIdtprelL32 %rs, @sym
1333     // Into:      %rd = ADDI %rs, sym@dtprel@l
1334     const MachineOperand &MO = MI->getOperand(2);
1335     const GlobalValue *GValue = MO.getGlobal();
1336     MCSymbol *MOSymbol = getSymbol(GValue);
1337     const MCExpr *SymDtprel =
1338       MCSymbolRefExpr::create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_LO,
1339                               OutContext);
1340     EmitToStreamer(*OutStreamer,
1341                    MCInstBuilder(IsPPC64 ? PPC::ADDI8 : PPC::ADDI)
1342                        .addReg(MI->getOperand(0).getReg())
1343                        .addReg(MI->getOperand(1).getReg())
1344                        .addExpr(SymDtprel));
1345     return;
1346   }
1347   case PPC::MFOCRF:
1348   case PPC::MFOCRF8:
1349     if (!Subtarget->hasMFOCRF()) {
1350       // Transform: %r3 = MFOCRF %cr7
1351       // Into:      %r3 = MFCR   ;; cr7
1352       unsigned NewOpcode =
1353         MI->getOpcode() == PPC::MFOCRF ? PPC::MFCR : PPC::MFCR8;
1354       OutStreamer->AddComment(PPCInstPrinter::
1355                               getRegisterName(MI->getOperand(1).getReg()));
1356       EmitToStreamer(*OutStreamer, MCInstBuilder(NewOpcode)
1357                                   .addReg(MI->getOperand(0).getReg()));
1358       return;
1359     }
1360     break;
1361   case PPC::MTOCRF:
1362   case PPC::MTOCRF8:
1363     if (!Subtarget->hasMFOCRF()) {
1364       // Transform: %cr7 = MTOCRF %r3
1365       // Into:      MTCRF mask, %r3 ;; cr7
1366       unsigned NewOpcode =
1367         MI->getOpcode() == PPC::MTOCRF ? PPC::MTCRF : PPC::MTCRF8;
1368       unsigned Mask = 0x80 >> OutContext.getRegisterInfo()
1369                               ->getEncodingValue(MI->getOperand(0).getReg());
1370       OutStreamer->AddComment(PPCInstPrinter::
1371                               getRegisterName(MI->getOperand(0).getReg()));
1372       EmitToStreamer(*OutStreamer, MCInstBuilder(NewOpcode)
1373                                      .addImm(Mask)
1374                                      .addReg(MI->getOperand(1).getReg()));
1375       return;
1376     }
1377     break;
1378   case PPC::LD:
1379   case PPC::STD:
1380   case PPC::LWA_32:
1381   case PPC::LWA: {
1382     // Verify alignment is legal, so we don't create relocations
1383     // that can't be supported.
1384     unsigned OpNum = (MI->getOpcode() == PPC::STD) ? 2 : 1;
1385     const MachineOperand &MO = MI->getOperand(OpNum);
1386     if (MO.isGlobal()) {
1387       const DataLayout &DL = MO.getGlobal()->getParent()->getDataLayout();
1388       if (MO.getGlobal()->getPointerAlignment(DL) < 4)
1389         llvm_unreachable("Global must be word-aligned for LD, STD, LWA!");
1390     }
1391     // Now process the instruction normally.
1392     break;
1393   }
1394   case PPC::PseudoEIEIO: {
1395     EmitToStreamer(
1396         *OutStreamer,
1397         MCInstBuilder(PPC::ORI).addReg(PPC::X2).addReg(PPC::X2).addImm(0));
1398     EmitToStreamer(
1399         *OutStreamer,
1400         MCInstBuilder(PPC::ORI).addReg(PPC::X2).addReg(PPC::X2).addImm(0));
1401     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::EnforceIEIO));
1402     return;
1403   }
1404   }
1405 
1406   LowerPPCMachineInstrToMCInst(MI, TmpInst, *this);
1407   EmitToStreamer(*OutStreamer, TmpInst);
1408 }
1409 
1410 void PPCLinuxAsmPrinter::emitGNUAttributes(Module &M) {
1411   // Emit float ABI into GNU attribute
1412   Metadata *MD = M.getModuleFlag("float-abi");
1413   MDString *FloatABI = dyn_cast_or_null<MDString>(MD);
1414   if (!FloatABI)
1415     return;
1416   StringRef flt = FloatABI->getString();
1417   // TODO: Support emitting soft-fp and hard double/single attributes.
1418   if (flt == "doubledouble")
1419     OutStreamer->emitGNUAttribute(Tag_GNU_Power_ABI_FP,
1420                                   Val_GNU_Power_ABI_HardFloat_DP |
1421                                       Val_GNU_Power_ABI_LDBL_IBM128);
1422   else if (flt == "ieeequad")
1423     OutStreamer->emitGNUAttribute(Tag_GNU_Power_ABI_FP,
1424                                   Val_GNU_Power_ABI_HardFloat_DP |
1425                                       Val_GNU_Power_ABI_LDBL_IEEE128);
1426   else if (flt == "ieeedouble")
1427     OutStreamer->emitGNUAttribute(Tag_GNU_Power_ABI_FP,
1428                                   Val_GNU_Power_ABI_HardFloat_DP |
1429                                       Val_GNU_Power_ABI_LDBL_64);
1430 }
1431 
1432 void PPCLinuxAsmPrinter::emitInstruction(const MachineInstr *MI) {
1433   if (!Subtarget->isPPC64())
1434     return PPCAsmPrinter::emitInstruction(MI);
1435 
1436   switch (MI->getOpcode()) {
1437   default:
1438     return PPCAsmPrinter::emitInstruction(MI);
1439   case TargetOpcode::PATCHABLE_FUNCTION_ENTER: {
1440     // .begin:
1441     //   b .end # lis 0, FuncId[16..32]
1442     //   nop    # li  0, FuncId[0..15]
1443     //   std 0, -8(1)
1444     //   mflr 0
1445     //   bl __xray_FunctionEntry
1446     //   mtlr 0
1447     // .end:
1448     //
1449     // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1450     // of instructions change.
1451     MCSymbol *BeginOfSled = OutContext.createTempSymbol();
1452     MCSymbol *EndOfSled = OutContext.createTempSymbol();
1453     OutStreamer->emitLabel(BeginOfSled);
1454     EmitToStreamer(*OutStreamer,
1455                    MCInstBuilder(PPC::B).addExpr(
1456                        MCSymbolRefExpr::create(EndOfSled, OutContext)));
1457     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
1458     EmitToStreamer(
1459         *OutStreamer,
1460         MCInstBuilder(PPC::STD).addReg(PPC::X0).addImm(-8).addReg(PPC::X1));
1461     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR8).addReg(PPC::X0));
1462     EmitToStreamer(*OutStreamer,
1463                    MCInstBuilder(PPC::BL8_NOP)
1464                        .addExpr(MCSymbolRefExpr::create(
1465                            OutContext.getOrCreateSymbol("__xray_FunctionEntry"),
1466                            OutContext)));
1467     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTLR8).addReg(PPC::X0));
1468     OutStreamer->emitLabel(EndOfSled);
1469     recordSled(BeginOfSled, *MI, SledKind::FUNCTION_ENTER, 2);
1470     break;
1471   }
1472   case TargetOpcode::PATCHABLE_RET: {
1473     unsigned RetOpcode = MI->getOperand(0).getImm();
1474     MCInst RetInst;
1475     RetInst.setOpcode(RetOpcode);
1476     for (const auto &MO : llvm::drop_begin(MI->operands())) {
1477       MCOperand MCOp;
1478       if (LowerPPCMachineOperandToMCOperand(MO, MCOp, *this))
1479         RetInst.addOperand(MCOp);
1480     }
1481 
1482     bool IsConditional;
1483     if (RetOpcode == PPC::BCCLR) {
1484       IsConditional = true;
1485     } else if (RetOpcode == PPC::TCRETURNdi8 || RetOpcode == PPC::TCRETURNri8 ||
1486                RetOpcode == PPC::TCRETURNai8) {
1487       break;
1488     } else if (RetOpcode == PPC::BLR8 || RetOpcode == PPC::TAILB8) {
1489       IsConditional = false;
1490     } else {
1491       EmitToStreamer(*OutStreamer, RetInst);
1492       break;
1493     }
1494 
1495     MCSymbol *FallthroughLabel;
1496     if (IsConditional) {
1497       // Before:
1498       //   bgtlr cr0
1499       //
1500       // After:
1501       //   ble cr0, .end
1502       // .p2align 3
1503       // .begin:
1504       //   blr    # lis 0, FuncId[16..32]
1505       //   nop    # li  0, FuncId[0..15]
1506       //   std 0, -8(1)
1507       //   mflr 0
1508       //   bl __xray_FunctionExit
1509       //   mtlr 0
1510       //   blr
1511       // .end:
1512       //
1513       // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1514       // of instructions change.
1515       FallthroughLabel = OutContext.createTempSymbol();
1516       EmitToStreamer(
1517           *OutStreamer,
1518           MCInstBuilder(PPC::BCC)
1519               .addImm(PPC::InvertPredicate(
1520                   static_cast<PPC::Predicate>(MI->getOperand(1).getImm())))
1521               .addReg(MI->getOperand(2).getReg())
1522               .addExpr(MCSymbolRefExpr::create(FallthroughLabel, OutContext)));
1523       RetInst = MCInst();
1524       RetInst.setOpcode(PPC::BLR8);
1525     }
1526     // .p2align 3
1527     // .begin:
1528     //   b(lr)? # lis 0, FuncId[16..32]
1529     //   nop    # li  0, FuncId[0..15]
1530     //   std 0, -8(1)
1531     //   mflr 0
1532     //   bl __xray_FunctionExit
1533     //   mtlr 0
1534     //   b(lr)?
1535     //
1536     // Update compiler-rt/lib/xray/xray_powerpc64.cc accordingly when number
1537     // of instructions change.
1538     OutStreamer->emitCodeAlignment(8, &getSubtargetInfo());
1539     MCSymbol *BeginOfSled = OutContext.createTempSymbol();
1540     OutStreamer->emitLabel(BeginOfSled);
1541     EmitToStreamer(*OutStreamer, RetInst);
1542     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::NOP));
1543     EmitToStreamer(
1544         *OutStreamer,
1545         MCInstBuilder(PPC::STD).addReg(PPC::X0).addImm(-8).addReg(PPC::X1));
1546     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MFLR8).addReg(PPC::X0));
1547     EmitToStreamer(*OutStreamer,
1548                    MCInstBuilder(PPC::BL8_NOP)
1549                        .addExpr(MCSymbolRefExpr::create(
1550                            OutContext.getOrCreateSymbol("__xray_FunctionExit"),
1551                            OutContext)));
1552     EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::MTLR8).addReg(PPC::X0));
1553     EmitToStreamer(*OutStreamer, RetInst);
1554     if (IsConditional)
1555       OutStreamer->emitLabel(FallthroughLabel);
1556     recordSled(BeginOfSled, *MI, SledKind::FUNCTION_EXIT, 2);
1557     break;
1558   }
1559   case TargetOpcode::PATCHABLE_FUNCTION_EXIT:
1560     llvm_unreachable("PATCHABLE_FUNCTION_EXIT should never be emitted");
1561   case TargetOpcode::PATCHABLE_TAIL_CALL:
1562     // TODO: Define a trampoline `__xray_FunctionTailExit` and differentiate a
1563     // normal function exit from a tail exit.
1564     llvm_unreachable("Tail call is handled in the normal case. See comments "
1565                      "around this assert.");
1566   }
1567 }
1568 
1569 void PPCLinuxAsmPrinter::emitStartOfAsmFile(Module &M) {
1570   if (static_cast<const PPCTargetMachine &>(TM).isELFv2ABI()) {
1571     PPCTargetStreamer *TS =
1572       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1573 
1574     if (TS)
1575       TS->emitAbiVersion(2);
1576   }
1577 
1578   if (static_cast<const PPCTargetMachine &>(TM).isPPC64() ||
1579       !isPositionIndependent())
1580     return AsmPrinter::emitStartOfAsmFile(M);
1581 
1582   if (M.getPICLevel() == PICLevel::SmallPIC)
1583     return AsmPrinter::emitStartOfAsmFile(M);
1584 
1585   OutStreamer->SwitchSection(OutContext.getELFSection(
1586       ".got2", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC));
1587 
1588   MCSymbol *TOCSym = OutContext.getOrCreateSymbol(Twine(".LTOC"));
1589   MCSymbol *CurrentPos = OutContext.createTempSymbol();
1590 
1591   OutStreamer->emitLabel(CurrentPos);
1592 
1593   // The GOT pointer points to the middle of the GOT, in order to reference the
1594   // entire 64kB range.  0x8000 is the midpoint.
1595   const MCExpr *tocExpr =
1596     MCBinaryExpr::createAdd(MCSymbolRefExpr::create(CurrentPos, OutContext),
1597                             MCConstantExpr::create(0x8000, OutContext),
1598                             OutContext);
1599 
1600   OutStreamer->emitAssignment(TOCSym, tocExpr);
1601 
1602   OutStreamer->SwitchSection(getObjFileLowering().getTextSection());
1603 }
1604 
1605 void PPCLinuxAsmPrinter::emitFunctionEntryLabel() {
1606   // linux/ppc32 - Normal entry label.
1607   if (!Subtarget->isPPC64() &&
1608       (!isPositionIndependent() ||
1609        MF->getFunction().getParent()->getPICLevel() == PICLevel::SmallPIC))
1610     return AsmPrinter::emitFunctionEntryLabel();
1611 
1612   if (!Subtarget->isPPC64()) {
1613     const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1614     if (PPCFI->usesPICBase() && !Subtarget->isSecurePlt()) {
1615       MCSymbol *RelocSymbol = PPCFI->getPICOffsetSymbol(*MF);
1616       MCSymbol *PICBase = MF->getPICBaseSymbol();
1617       OutStreamer->emitLabel(RelocSymbol);
1618 
1619       const MCExpr *OffsExpr =
1620         MCBinaryExpr::createSub(
1621           MCSymbolRefExpr::create(OutContext.getOrCreateSymbol(Twine(".LTOC")),
1622                                                                OutContext),
1623                                   MCSymbolRefExpr::create(PICBase, OutContext),
1624           OutContext);
1625       OutStreamer->emitValue(OffsExpr, 4);
1626       OutStreamer->emitLabel(CurrentFnSym);
1627       return;
1628     } else
1629       return AsmPrinter::emitFunctionEntryLabel();
1630   }
1631 
1632   // ELFv2 ABI - Normal entry label.
1633   if (Subtarget->isELFv2ABI()) {
1634     // In the Large code model, we allow arbitrary displacements between
1635     // the text section and its associated TOC section.  We place the
1636     // full 8-byte offset to the TOC in memory immediately preceding
1637     // the function global entry point.
1638     if (TM.getCodeModel() == CodeModel::Large
1639         && !MF->getRegInfo().use_empty(PPC::X2)) {
1640       const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1641 
1642       MCSymbol *TOCSymbol = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1643       MCSymbol *GlobalEPSymbol = PPCFI->getGlobalEPSymbol(*MF);
1644       const MCExpr *TOCDeltaExpr =
1645         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCSymbol, OutContext),
1646                                 MCSymbolRefExpr::create(GlobalEPSymbol,
1647                                                         OutContext),
1648                                 OutContext);
1649 
1650       OutStreamer->emitLabel(PPCFI->getTOCOffsetSymbol(*MF));
1651       OutStreamer->emitValue(TOCDeltaExpr, 8);
1652     }
1653     return AsmPrinter::emitFunctionEntryLabel();
1654   }
1655 
1656   // Emit an official procedure descriptor.
1657   MCSectionSubPair Current = OutStreamer->getCurrentSection();
1658   MCSectionELF *Section = OutStreamer->getContext().getELFSection(
1659       ".opd", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
1660   OutStreamer->SwitchSection(Section);
1661   OutStreamer->emitLabel(CurrentFnSym);
1662   OutStreamer->emitValueToAlignment(8);
1663   MCSymbol *Symbol1 = CurrentFnSymForSize;
1664   // Generates a R_PPC64_ADDR64 (from FK_DATA_8) relocation for the function
1665   // entry point.
1666   OutStreamer->emitValue(MCSymbolRefExpr::create(Symbol1, OutContext),
1667                          8 /*size*/);
1668   MCSymbol *Symbol2 = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1669   // Generates a R_PPC64_TOC relocation for TOC base insertion.
1670   OutStreamer->emitValue(
1671     MCSymbolRefExpr::create(Symbol2, MCSymbolRefExpr::VK_PPC_TOCBASE, OutContext),
1672     8/*size*/);
1673   // Emit a null environment pointer.
1674   OutStreamer->emitIntValue(0, 8 /* size */);
1675   OutStreamer->SwitchSection(Current.first, Current.second);
1676 }
1677 
1678 void PPCLinuxAsmPrinter::emitEndOfAsmFile(Module &M) {
1679   const DataLayout &DL = getDataLayout();
1680 
1681   bool isPPC64 = DL.getPointerSizeInBits() == 64;
1682 
1683   PPCTargetStreamer *TS =
1684       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1685 
1686   emitGNUAttributes(M);
1687 
1688   if (!TOC.empty()) {
1689     const char *Name = isPPC64 ? ".toc" : ".got2";
1690     MCSectionELF *Section = OutContext.getELFSection(
1691         Name, ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
1692     OutStreamer->SwitchSection(Section);
1693     if (!isPPC64)
1694       OutStreamer->emitValueToAlignment(4);
1695 
1696     for (const auto &TOCMapPair : TOC) {
1697       const MCSymbol *const TOCEntryTarget = TOCMapPair.first.first;
1698       MCSymbol *const TOCEntryLabel = TOCMapPair.second;
1699 
1700       OutStreamer->emitLabel(TOCEntryLabel);
1701       if (isPPC64 && TS != nullptr)
1702         TS->emitTCEntry(*TOCEntryTarget, TOCMapPair.first.second);
1703       else
1704         OutStreamer->emitSymbolValue(TOCEntryTarget, 4);
1705     }
1706   }
1707 
1708   PPCAsmPrinter::emitEndOfAsmFile(M);
1709 }
1710 
1711 /// EmitFunctionBodyStart - Emit a global entry point prefix for ELFv2.
1712 void PPCLinuxAsmPrinter::emitFunctionBodyStart() {
1713   // In the ELFv2 ABI, in functions that use the TOC register, we need to
1714   // provide two entry points.  The ABI guarantees that when calling the
1715   // local entry point, r2 is set up by the caller to contain the TOC base
1716   // for this function, and when calling the global entry point, r12 is set
1717   // up by the caller to hold the address of the global entry point.  We
1718   // thus emit a prefix sequence along the following lines:
1719   //
1720   // func:
1721   // .Lfunc_gepNN:
1722   //         # global entry point
1723   //         addis r2,r12,(.TOC.-.Lfunc_gepNN)@ha
1724   //         addi  r2,r2,(.TOC.-.Lfunc_gepNN)@l
1725   // .Lfunc_lepNN:
1726   //         .localentry func, .Lfunc_lepNN-.Lfunc_gepNN
1727   //         # local entry point, followed by function body
1728   //
1729   // For the Large code model, we create
1730   //
1731   // .Lfunc_tocNN:
1732   //         .quad .TOC.-.Lfunc_gepNN      # done by EmitFunctionEntryLabel
1733   // func:
1734   // .Lfunc_gepNN:
1735   //         # global entry point
1736   //         ld    r2,.Lfunc_tocNN-.Lfunc_gepNN(r12)
1737   //         add   r2,r2,r12
1738   // .Lfunc_lepNN:
1739   //         .localentry func, .Lfunc_lepNN-.Lfunc_gepNN
1740   //         # local entry point, followed by function body
1741   //
1742   // This ensures we have r2 set up correctly while executing the function
1743   // body, no matter which entry point is called.
1744   const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
1745   const bool UsesX2OrR2 = !MF->getRegInfo().use_empty(PPC::X2) ||
1746                           !MF->getRegInfo().use_empty(PPC::R2);
1747   const bool PCrelGEPRequired = Subtarget->isUsingPCRelativeCalls() &&
1748                                 UsesX2OrR2 && PPCFI->usesTOCBasePtr();
1749   const bool NonPCrelGEPRequired = !Subtarget->isUsingPCRelativeCalls() &&
1750                                    Subtarget->isELFv2ABI() && UsesX2OrR2;
1751 
1752   // Only do all that if the function uses R2 as the TOC pointer
1753   // in the first place. We don't need the global entry point if the
1754   // function uses R2 as an allocatable register.
1755   if (NonPCrelGEPRequired || PCrelGEPRequired) {
1756     // Note: The logic here must be synchronized with the code in the
1757     // branch-selection pass which sets the offset of the first block in the
1758     // function. This matters because it affects the alignment.
1759     MCSymbol *GlobalEntryLabel = PPCFI->getGlobalEPSymbol(*MF);
1760     OutStreamer->emitLabel(GlobalEntryLabel);
1761     const MCSymbolRefExpr *GlobalEntryLabelExp =
1762       MCSymbolRefExpr::create(GlobalEntryLabel, OutContext);
1763 
1764     if (TM.getCodeModel() != CodeModel::Large) {
1765       MCSymbol *TOCSymbol = OutContext.getOrCreateSymbol(StringRef(".TOC."));
1766       const MCExpr *TOCDeltaExpr =
1767         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCSymbol, OutContext),
1768                                 GlobalEntryLabelExp, OutContext);
1769 
1770       const MCExpr *TOCDeltaHi = PPCMCExpr::createHa(TOCDeltaExpr, OutContext);
1771       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDIS)
1772                                    .addReg(PPC::X2)
1773                                    .addReg(PPC::X12)
1774                                    .addExpr(TOCDeltaHi));
1775 
1776       const MCExpr *TOCDeltaLo = PPCMCExpr::createLo(TOCDeltaExpr, OutContext);
1777       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADDI)
1778                                    .addReg(PPC::X2)
1779                                    .addReg(PPC::X2)
1780                                    .addExpr(TOCDeltaLo));
1781     } else {
1782       MCSymbol *TOCOffset = PPCFI->getTOCOffsetSymbol(*MF);
1783       const MCExpr *TOCOffsetDeltaExpr =
1784         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCOffset, OutContext),
1785                                 GlobalEntryLabelExp, OutContext);
1786 
1787       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::LD)
1788                                    .addReg(PPC::X2)
1789                                    .addExpr(TOCOffsetDeltaExpr)
1790                                    .addReg(PPC::X12));
1791       EmitToStreamer(*OutStreamer, MCInstBuilder(PPC::ADD8)
1792                                    .addReg(PPC::X2)
1793                                    .addReg(PPC::X2)
1794                                    .addReg(PPC::X12));
1795     }
1796 
1797     MCSymbol *LocalEntryLabel = PPCFI->getLocalEPSymbol(*MF);
1798     OutStreamer->emitLabel(LocalEntryLabel);
1799     const MCSymbolRefExpr *LocalEntryLabelExp =
1800        MCSymbolRefExpr::create(LocalEntryLabel, OutContext);
1801     const MCExpr *LocalOffsetExp =
1802       MCBinaryExpr::createSub(LocalEntryLabelExp,
1803                               GlobalEntryLabelExp, OutContext);
1804 
1805     PPCTargetStreamer *TS =
1806       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1807 
1808     if (TS)
1809       TS->emitLocalEntry(cast<MCSymbolELF>(CurrentFnSym), LocalOffsetExp);
1810   } else if (Subtarget->isUsingPCRelativeCalls()) {
1811     // When generating the entry point for a function we have a few scenarios
1812     // based on whether or not that function uses R2 and whether or not that
1813     // function makes calls (or is a leaf function).
1814     // 1) A leaf function that does not use R2 (or treats it as callee-saved
1815     //    and preserves it). In this case st_other=0 and both
1816     //    the local and global entry points for the function are the same.
1817     //    No special entry point code is required.
1818     // 2) A function uses the TOC pointer R2. This function may or may not have
1819     //    calls. In this case st_other=[2,6] and the global and local entry
1820     //    points are different. Code to correctly setup the TOC pointer in R2
1821     //    is put between the global and local entry points. This case is
1822     //    covered by the if statatement above.
1823     // 3) A function does not use the TOC pointer R2 but does have calls.
1824     //    In this case st_other=1 since we do not know whether or not any
1825     //    of the callees clobber R2. This case is dealt with in this else if
1826     //    block. Tail calls are considered calls and the st_other should also
1827     //    be set to 1 in that case as well.
1828     // 4) The function does not use the TOC pointer but R2 is used inside
1829     //    the function. In this case st_other=1 once again.
1830     // 5) This function uses inline asm. We mark R2 as reserved if the function
1831     //    has inline asm as we have to assume that it may be used.
1832     if (MF->getFrameInfo().hasCalls() || MF->getFrameInfo().hasTailCall() ||
1833         MF->hasInlineAsm() || (!PPCFI->usesTOCBasePtr() && UsesX2OrR2)) {
1834       PPCTargetStreamer *TS =
1835           static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
1836       if (TS)
1837         TS->emitLocalEntry(cast<MCSymbolELF>(CurrentFnSym),
1838                            MCConstantExpr::create(1, OutContext));
1839     }
1840   }
1841 }
1842 
1843 /// EmitFunctionBodyEnd - Print the traceback table before the .size
1844 /// directive.
1845 ///
1846 void PPCLinuxAsmPrinter::emitFunctionBodyEnd() {
1847   // Only the 64-bit target requires a traceback table.  For now,
1848   // we only emit the word of zeroes that GDB requires to find
1849   // the end of the function, and zeroes for the eight-byte
1850   // mandatory fields.
1851   // FIXME: We should fill in the eight-byte mandatory fields as described in
1852   // the PPC64 ELF ABI (this is a low-priority item because GDB does not
1853   // currently make use of these fields).
1854   if (Subtarget->isPPC64()) {
1855     OutStreamer->emitIntValue(0, 4/*size*/);
1856     OutStreamer->emitIntValue(0, 8/*size*/);
1857   }
1858 }
1859 
1860 void PPCAIXAsmPrinter::emitLinkage(const GlobalValue *GV,
1861                                    MCSymbol *GVSym) const {
1862 
1863   assert(MAI->hasVisibilityOnlyWithLinkage() &&
1864          "AIX's linkage directives take a visibility setting.");
1865 
1866   MCSymbolAttr LinkageAttr = MCSA_Invalid;
1867   switch (GV->getLinkage()) {
1868   case GlobalValue::ExternalLinkage:
1869     LinkageAttr = GV->isDeclaration() ? MCSA_Extern : MCSA_Global;
1870     break;
1871   case GlobalValue::LinkOnceAnyLinkage:
1872   case GlobalValue::LinkOnceODRLinkage:
1873   case GlobalValue::WeakAnyLinkage:
1874   case GlobalValue::WeakODRLinkage:
1875   case GlobalValue::ExternalWeakLinkage:
1876     LinkageAttr = MCSA_Weak;
1877     break;
1878   case GlobalValue::AvailableExternallyLinkage:
1879     LinkageAttr = MCSA_Extern;
1880     break;
1881   case GlobalValue::PrivateLinkage:
1882     return;
1883   case GlobalValue::InternalLinkage:
1884     assert(GV->getVisibility() == GlobalValue::DefaultVisibility &&
1885            "InternalLinkage should not have other visibility setting.");
1886     LinkageAttr = MCSA_LGlobal;
1887     break;
1888   case GlobalValue::AppendingLinkage:
1889     llvm_unreachable("Should never emit this");
1890   case GlobalValue::CommonLinkage:
1891     llvm_unreachable("CommonLinkage of XCOFF should not come to this path");
1892   }
1893 
1894   assert(LinkageAttr != MCSA_Invalid && "LinkageAttr should not MCSA_Invalid.");
1895 
1896   MCSymbolAttr VisibilityAttr = MCSA_Invalid;
1897   if (!TM.getIgnoreXCOFFVisibility()) {
1898     switch (GV->getVisibility()) {
1899 
1900     // TODO: "exported" and "internal" Visibility needs to go here.
1901     case GlobalValue::DefaultVisibility:
1902       break;
1903     case GlobalValue::HiddenVisibility:
1904       VisibilityAttr = MAI->getHiddenVisibilityAttr();
1905       break;
1906     case GlobalValue::ProtectedVisibility:
1907       VisibilityAttr = MAI->getProtectedVisibilityAttr();
1908       break;
1909     }
1910   }
1911 
1912   OutStreamer->emitXCOFFSymbolLinkageWithVisibility(GVSym, LinkageAttr,
1913                                                     VisibilityAttr);
1914 }
1915 
1916 void PPCAIXAsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1917   // Setup CurrentFnDescSym and its containing csect.
1918   MCSectionXCOFF *FnDescSec =
1919       cast<MCSectionXCOFF>(getObjFileLowering().getSectionForFunctionDescriptor(
1920           &MF.getFunction(), TM));
1921   FnDescSec->setAlignment(Align(Subtarget->isPPC64() ? 8 : 4));
1922 
1923   CurrentFnDescSym = FnDescSec->getQualNameSymbol();
1924 
1925   return AsmPrinter::SetupMachineFunction(MF);
1926 }
1927 
1928 uint16_t PPCAIXAsmPrinter::getNumberOfVRSaved() {
1929   // Calculate the number of VRs be saved.
1930   // Vector registers 20 through 31 are marked as reserved and cannot be used
1931   // in the default ABI.
1932   const PPCSubtarget &Subtarget = MF->getSubtarget<PPCSubtarget>();
1933   if (Subtarget.isAIXABI() && Subtarget.hasAltivec() &&
1934       TM.getAIXExtendedAltivecABI()) {
1935     const MachineRegisterInfo &MRI = MF->getRegInfo();
1936     for (unsigned Reg = PPC::V20; Reg <= PPC::V31; ++Reg)
1937       if (MRI.isPhysRegModified(Reg))
1938         // Number of VRs saved.
1939         return PPC::V31 - Reg + 1;
1940   }
1941   return 0;
1942 }
1943 
1944 void PPCAIXAsmPrinter::emitFunctionBodyEnd() {
1945 
1946   if (!TM.getXCOFFTracebackTable())
1947     return;
1948 
1949   emitTracebackTable();
1950 
1951   // If ShouldEmitEHBlock returns true, then the eh info table
1952   // will be emitted via `AIXException::endFunction`. Otherwise, we
1953   // need to emit a dumy eh info table when VRs are saved. We could not
1954   // consolidate these two places into one because there is no easy way
1955   // to access register information in `AIXException` class.
1956   if (!TargetLoweringObjectFileXCOFF::ShouldEmitEHBlock(MF) &&
1957       (getNumberOfVRSaved() > 0)) {
1958     // Emit dummy EH Info Table.
1959     OutStreamer->SwitchSection(getObjFileLowering().getCompactUnwindSection());
1960     MCSymbol *EHInfoLabel =
1961         TargetLoweringObjectFileXCOFF::getEHInfoTableSymbol(MF);
1962     OutStreamer->emitLabel(EHInfoLabel);
1963 
1964     // Version number.
1965     OutStreamer->emitInt32(0);
1966 
1967     const DataLayout &DL = MMI->getModule()->getDataLayout();
1968     const unsigned PointerSize = DL.getPointerSize();
1969     // Add necessary paddings in 64 bit mode.
1970     OutStreamer->emitValueToAlignment(PointerSize);
1971 
1972     OutStreamer->emitIntValue(0, PointerSize);
1973     OutStreamer->emitIntValue(0, PointerSize);
1974     OutStreamer->SwitchSection(MF->getSection());
1975   }
1976 }
1977 
1978 void PPCAIXAsmPrinter::emitTracebackTable() {
1979 
1980   // Create a symbol for the end of function.
1981   MCSymbol *FuncEnd = createTempSymbol(MF->getName());
1982   OutStreamer->emitLabel(FuncEnd);
1983 
1984   OutStreamer->AddComment("Traceback table begin");
1985   // Begin with a fullword of zero.
1986   OutStreamer->emitIntValueInHexWithPadding(0, 4 /*size*/);
1987 
1988   SmallString<128> CommentString;
1989   raw_svector_ostream CommentOS(CommentString);
1990 
1991   auto EmitComment = [&]() {
1992     OutStreamer->AddComment(CommentOS.str());
1993     CommentString.clear();
1994   };
1995 
1996   auto EmitCommentAndValue = [&](uint64_t Value, int Size) {
1997     EmitComment();
1998     OutStreamer->emitIntValueInHexWithPadding(Value, Size);
1999   };
2000 
2001   unsigned int Version = 0;
2002   CommentOS << "Version = " << Version;
2003   EmitCommentAndValue(Version, 1);
2004 
2005   // There is a lack of information in the IR to assist with determining the
2006   // source language. AIX exception handling mechanism would only search for
2007   // personality routine and LSDA area when such language supports exception
2008   // handling. So to be conservatively correct and allow runtime to do its job,
2009   // we need to set it to C++ for now.
2010   TracebackTable::LanguageID LanguageIdentifier =
2011       TracebackTable::CPlusPlus; // C++
2012 
2013   CommentOS << "Language = "
2014             << getNameForTracebackTableLanguageId(LanguageIdentifier);
2015   EmitCommentAndValue(LanguageIdentifier, 1);
2016 
2017   //  This is only populated for the third and fourth bytes.
2018   uint32_t FirstHalfOfMandatoryField = 0;
2019 
2020   // Emit the 3rd byte of the mandatory field.
2021 
2022   // We always set traceback offset bit to true.
2023   FirstHalfOfMandatoryField |= TracebackTable::HasTraceBackTableOffsetMask;
2024 
2025   const PPCFunctionInfo *FI = MF->getInfo<PPCFunctionInfo>();
2026   const MachineRegisterInfo &MRI = MF->getRegInfo();
2027 
2028   // Check the function uses floating-point processor instructions or not
2029   for (unsigned Reg = PPC::F0; Reg <= PPC::F31; ++Reg) {
2030     if (MRI.isPhysRegUsed(Reg, /* SkipRegMaskTest */ true)) {
2031       FirstHalfOfMandatoryField |= TracebackTable::IsFloatingPointPresentMask;
2032       break;
2033     }
2034   }
2035 
2036 #define GENBOOLCOMMENT(Prefix, V, Field)                                       \
2037   CommentOS << (Prefix) << ((V) & (TracebackTable::Field##Mask) ? "+" : "-")   \
2038             << #Field
2039 
2040 #define GENVALUECOMMENT(PrefixAndName, V, Field)                               \
2041   CommentOS << (PrefixAndName) << " = "                                        \
2042             << static_cast<unsigned>(((V) & (TracebackTable::Field##Mask)) >>  \
2043                                      (TracebackTable::Field##Shift))
2044 
2045   GENBOOLCOMMENT("", FirstHalfOfMandatoryField, IsGlobaLinkage);
2046   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsOutOfLineEpilogOrPrologue);
2047   EmitComment();
2048 
2049   GENBOOLCOMMENT("", FirstHalfOfMandatoryField, HasTraceBackTableOffset);
2050   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsInternalProcedure);
2051   EmitComment();
2052 
2053   GENBOOLCOMMENT("", FirstHalfOfMandatoryField, HasControlledStorage);
2054   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsTOCless);
2055   EmitComment();
2056 
2057   GENBOOLCOMMENT("", FirstHalfOfMandatoryField, IsFloatingPointPresent);
2058   EmitComment();
2059   GENBOOLCOMMENT("", FirstHalfOfMandatoryField,
2060                  IsFloatingPointOperationLogOrAbortEnabled);
2061   EmitComment();
2062 
2063   OutStreamer->emitIntValueInHexWithPadding(
2064       (FirstHalfOfMandatoryField & 0x0000ff00) >> 8, 1);
2065 
2066   // Set the 4th byte of the mandatory field.
2067   FirstHalfOfMandatoryField |= TracebackTable::IsFunctionNamePresentMask;
2068 
2069   const PPCRegisterInfo *RegInfo =
2070       static_cast<const PPCRegisterInfo *>(Subtarget->getRegisterInfo());
2071   Register FrameReg = RegInfo->getFrameRegister(*MF);
2072   if (FrameReg == (Subtarget->isPPC64() ? PPC::X31 : PPC::R31))
2073     FirstHalfOfMandatoryField |= TracebackTable::IsAllocaUsedMask;
2074 
2075   const SmallVectorImpl<Register> &MustSaveCRs = FI->getMustSaveCRs();
2076   if (!MustSaveCRs.empty())
2077     FirstHalfOfMandatoryField |= TracebackTable::IsCRSavedMask;
2078 
2079   if (FI->mustSaveLR())
2080     FirstHalfOfMandatoryField |= TracebackTable::IsLRSavedMask;
2081 
2082   GENBOOLCOMMENT("", FirstHalfOfMandatoryField, IsInterruptHandler);
2083   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsFunctionNamePresent);
2084   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsAllocaUsed);
2085   EmitComment();
2086   GENVALUECOMMENT("OnConditionDirective", FirstHalfOfMandatoryField,
2087                   OnConditionDirective);
2088   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsCRSaved);
2089   GENBOOLCOMMENT(", ", FirstHalfOfMandatoryField, IsLRSaved);
2090   EmitComment();
2091   OutStreamer->emitIntValueInHexWithPadding((FirstHalfOfMandatoryField & 0xff),
2092                                             1);
2093 
2094   // Set the 5th byte of mandatory field.
2095   uint32_t SecondHalfOfMandatoryField = 0;
2096 
2097   // Always store back chain.
2098   SecondHalfOfMandatoryField |= TracebackTable::IsBackChainStoredMask;
2099 
2100   uint32_t FPRSaved = 0;
2101   for (unsigned Reg = PPC::F14; Reg <= PPC::F31; ++Reg) {
2102     if (MRI.isPhysRegModified(Reg)) {
2103       FPRSaved = PPC::F31 - Reg + 1;
2104       break;
2105     }
2106   }
2107   SecondHalfOfMandatoryField |= (FPRSaved << TracebackTable::FPRSavedShift) &
2108                                 TracebackTable::FPRSavedMask;
2109   GENBOOLCOMMENT("", SecondHalfOfMandatoryField, IsBackChainStored);
2110   GENBOOLCOMMENT(", ", SecondHalfOfMandatoryField, IsFixup);
2111   GENVALUECOMMENT(", NumOfFPRsSaved", SecondHalfOfMandatoryField, FPRSaved);
2112   EmitComment();
2113   OutStreamer->emitIntValueInHexWithPadding(
2114       (SecondHalfOfMandatoryField & 0xff000000) >> 24, 1);
2115 
2116   // Set the 6th byte of mandatory field.
2117 
2118   // Check whether has Vector Instruction,We only treat instructions uses vector
2119   // register as vector instructions.
2120   bool HasVectorInst = false;
2121   for (unsigned Reg = PPC::V0; Reg <= PPC::V31; ++Reg)
2122     if (MRI.isPhysRegUsed(Reg, /* SkipRegMaskTest */ true)) {
2123       // Has VMX instruction.
2124       HasVectorInst = true;
2125       break;
2126     }
2127 
2128   if (FI->hasVectorParms() || HasVectorInst)
2129     SecondHalfOfMandatoryField |= TracebackTable::HasVectorInfoMask;
2130 
2131   uint16_t NumOfVRSaved = getNumberOfVRSaved();
2132   bool ShouldEmitEHBlock =
2133       TargetLoweringObjectFileXCOFF::ShouldEmitEHBlock(MF) || NumOfVRSaved > 0;
2134 
2135   if (ShouldEmitEHBlock)
2136     SecondHalfOfMandatoryField |= TracebackTable::HasExtensionTableMask;
2137 
2138   uint32_t GPRSaved = 0;
2139 
2140   // X13 is reserved under 64-bit environment.
2141   unsigned GPRBegin = Subtarget->isPPC64() ? PPC::X14 : PPC::R13;
2142   unsigned GPREnd = Subtarget->isPPC64() ? PPC::X31 : PPC::R31;
2143 
2144   for (unsigned Reg = GPRBegin; Reg <= GPREnd; ++Reg) {
2145     if (MRI.isPhysRegModified(Reg)) {
2146       GPRSaved = GPREnd - Reg + 1;
2147       break;
2148     }
2149   }
2150 
2151   SecondHalfOfMandatoryField |= (GPRSaved << TracebackTable::GPRSavedShift) &
2152                                 TracebackTable::GPRSavedMask;
2153 
2154   GENBOOLCOMMENT("", SecondHalfOfMandatoryField, HasExtensionTable);
2155   GENBOOLCOMMENT(", ", SecondHalfOfMandatoryField, HasVectorInfo);
2156   GENVALUECOMMENT(", NumOfGPRsSaved", SecondHalfOfMandatoryField, GPRSaved);
2157   EmitComment();
2158   OutStreamer->emitIntValueInHexWithPadding(
2159       (SecondHalfOfMandatoryField & 0x00ff0000) >> 16, 1);
2160 
2161   // Set the 7th byte of mandatory field.
2162   uint32_t NumberOfFixedParms = FI->getFixedParmsNum();
2163   SecondHalfOfMandatoryField |=
2164       (NumberOfFixedParms << TracebackTable::NumberOfFixedParmsShift) &
2165       TracebackTable::NumberOfFixedParmsMask;
2166   GENVALUECOMMENT("NumberOfFixedParms", SecondHalfOfMandatoryField,
2167                   NumberOfFixedParms);
2168   EmitComment();
2169   OutStreamer->emitIntValueInHexWithPadding(
2170       (SecondHalfOfMandatoryField & 0x0000ff00) >> 8, 1);
2171 
2172   // Set the 8th byte of mandatory field.
2173 
2174   // Always set parameter on stack.
2175   SecondHalfOfMandatoryField |= TracebackTable::HasParmsOnStackMask;
2176 
2177   uint32_t NumberOfFPParms = FI->getFloatingPointParmsNum();
2178   SecondHalfOfMandatoryField |=
2179       (NumberOfFPParms << TracebackTable::NumberOfFloatingPointParmsShift) &
2180       TracebackTable::NumberOfFloatingPointParmsMask;
2181 
2182   GENVALUECOMMENT("NumberOfFPParms", SecondHalfOfMandatoryField,
2183                   NumberOfFloatingPointParms);
2184   GENBOOLCOMMENT(", ", SecondHalfOfMandatoryField, HasParmsOnStack);
2185   EmitComment();
2186   OutStreamer->emitIntValueInHexWithPadding(SecondHalfOfMandatoryField & 0xff,
2187                                             1);
2188 
2189   // Generate the optional fields of traceback table.
2190 
2191   // Parameter type.
2192   if (NumberOfFixedParms || NumberOfFPParms) {
2193     uint32_t ParmsTypeValue = FI->getParmsType();
2194 
2195     Expected<SmallString<32>> ParmsType =
2196         FI->hasVectorParms()
2197             ? XCOFF::parseParmsTypeWithVecInfo(
2198                   ParmsTypeValue, NumberOfFixedParms, NumberOfFPParms,
2199                   FI->getVectorParmsNum())
2200             : XCOFF::parseParmsType(ParmsTypeValue, NumberOfFixedParms,
2201                                     NumberOfFPParms);
2202 
2203     assert(ParmsType && toString(ParmsType.takeError()).c_str());
2204     if (ParmsType) {
2205       CommentOS << "Parameter type = " << ParmsType.get();
2206       EmitComment();
2207     }
2208     OutStreamer->emitIntValueInHexWithPadding(ParmsTypeValue,
2209                                               sizeof(ParmsTypeValue));
2210   }
2211   // Traceback table offset.
2212   OutStreamer->AddComment("Function size");
2213   if (FirstHalfOfMandatoryField & TracebackTable::HasTraceBackTableOffsetMask) {
2214     MCSymbol *FuncSectSym = getObjFileLowering().getFunctionEntryPointSymbol(
2215         &(MF->getFunction()), TM);
2216     OutStreamer->emitAbsoluteSymbolDiff(FuncEnd, FuncSectSym, 4);
2217   }
2218 
2219   // Since we unset the Int_Handler.
2220   if (FirstHalfOfMandatoryField & TracebackTable::IsInterruptHandlerMask)
2221     report_fatal_error("Hand_Mask not implement yet");
2222 
2223   if (FirstHalfOfMandatoryField & TracebackTable::HasControlledStorageMask)
2224     report_fatal_error("Ctl_Info not implement yet");
2225 
2226   if (FirstHalfOfMandatoryField & TracebackTable::IsFunctionNamePresentMask) {
2227     StringRef Name = MF->getName().substr(0, INT16_MAX);
2228     int16_t NameLength = Name.size();
2229     CommentOS << "Function name len = "
2230               << static_cast<unsigned int>(NameLength);
2231     EmitCommentAndValue(NameLength, 2);
2232     OutStreamer->AddComment("Function Name");
2233     OutStreamer->emitBytes(Name);
2234   }
2235 
2236   if (FirstHalfOfMandatoryField & TracebackTable::IsAllocaUsedMask) {
2237     uint8_t AllocReg = XCOFF::AllocRegNo;
2238     OutStreamer->AddComment("AllocaUsed");
2239     OutStreamer->emitIntValueInHex(AllocReg, sizeof(AllocReg));
2240   }
2241 
2242   if (SecondHalfOfMandatoryField & TracebackTable::HasVectorInfoMask) {
2243     uint16_t VRData = 0;
2244     if (NumOfVRSaved) {
2245       // Number of VRs saved.
2246       VRData |= (NumOfVRSaved << TracebackTable::NumberOfVRSavedShift) &
2247                 TracebackTable::NumberOfVRSavedMask;
2248       // This bit is supposed to set only when the special register
2249       // VRSAVE is saved on stack.
2250       // However, IBM XL compiler sets the bit when any vector registers
2251       // are saved on the stack. We will follow XL's behavior on AIX
2252       // so that we don't get surprise behavior change for C code.
2253       VRData |= TracebackTable::IsVRSavedOnStackMask;
2254     }
2255 
2256     // Set has_varargs.
2257     if (FI->getVarArgsFrameIndex())
2258       VRData |= TracebackTable::HasVarArgsMask;
2259 
2260     // Vector parameters number.
2261     unsigned VectorParmsNum = FI->getVectorParmsNum();
2262     VRData |= (VectorParmsNum << TracebackTable::NumberOfVectorParmsShift) &
2263               TracebackTable::NumberOfVectorParmsMask;
2264 
2265     if (HasVectorInst)
2266       VRData |= TracebackTable::HasVMXInstructionMask;
2267 
2268     GENVALUECOMMENT("NumOfVRsSaved", VRData, NumberOfVRSaved);
2269     GENBOOLCOMMENT(", ", VRData, IsVRSavedOnStack);
2270     GENBOOLCOMMENT(", ", VRData, HasVarArgs);
2271     EmitComment();
2272     OutStreamer->emitIntValueInHexWithPadding((VRData & 0xff00) >> 8, 1);
2273 
2274     GENVALUECOMMENT("NumOfVectorParams", VRData, NumberOfVectorParms);
2275     GENBOOLCOMMENT(", ", VRData, HasVMXInstruction);
2276     EmitComment();
2277     OutStreamer->emitIntValueInHexWithPadding(VRData & 0x00ff, 1);
2278 
2279     uint32_t VecParmTypeValue = FI->getVecExtParmsType();
2280 
2281     Expected<SmallString<32>> VecParmsType =
2282         XCOFF::parseVectorParmsType(VecParmTypeValue, VectorParmsNum);
2283     assert(VecParmsType && toString(VecParmsType.takeError()).c_str());
2284     if (VecParmsType) {
2285       CommentOS << "Vector Parameter type = " << VecParmsType.get();
2286       EmitComment();
2287     }
2288     OutStreamer->emitIntValueInHexWithPadding(VecParmTypeValue,
2289                                               sizeof(VecParmTypeValue));
2290     // Padding 2 bytes.
2291     CommentOS << "Padding";
2292     EmitCommentAndValue(0, 2);
2293   }
2294 
2295   uint8_t ExtensionTableFlag = 0;
2296   if (SecondHalfOfMandatoryField & TracebackTable::HasExtensionTableMask) {
2297     if (ShouldEmitEHBlock)
2298       ExtensionTableFlag |= ExtendedTBTableFlag::TB_EH_INFO;
2299     if (EnableSSPCanaryBitInTB &&
2300         TargetLoweringObjectFileXCOFF::ShouldSetSSPCanaryBitInTB(MF))
2301       ExtensionTableFlag |= ExtendedTBTableFlag::TB_SSP_CANARY;
2302 
2303     CommentOS << "ExtensionTableFlag = "
2304               << getExtendedTBTableFlagString(ExtensionTableFlag);
2305     EmitCommentAndValue(ExtensionTableFlag, sizeof(ExtensionTableFlag));
2306   }
2307 
2308   if (ExtensionTableFlag & ExtendedTBTableFlag::TB_EH_INFO) {
2309     auto &Ctx = OutStreamer->getContext();
2310     MCSymbol *EHInfoSym =
2311         TargetLoweringObjectFileXCOFF::getEHInfoTableSymbol(MF);
2312     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(EHInfoSym);
2313     const MCSymbol *TOCBaseSym =
2314         cast<MCSectionXCOFF>(getObjFileLowering().getTOCBaseSection())
2315             ->getQualNameSymbol();
2316     const MCExpr *Exp =
2317         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCEntry, Ctx),
2318                                 MCSymbolRefExpr::create(TOCBaseSym, Ctx), Ctx);
2319 
2320     const DataLayout &DL = getDataLayout();
2321     OutStreamer->emitValueToAlignment(4);
2322     OutStreamer->AddComment("EHInfo Table");
2323     OutStreamer->emitValue(Exp, DL.getPointerSize());
2324   }
2325 #undef GENBOOLCOMMENT
2326 #undef GENVALUECOMMENT
2327 }
2328 
2329 static bool isSpecialLLVMGlobalArrayToSkip(const GlobalVariable *GV) {
2330   return GV->hasAppendingLinkage() &&
2331          StringSwitch<bool>(GV->getName())
2332              // TODO: Linker could still eliminate the GV if we just skip
2333              // handling llvm.used array. Skipping them for now until we or the
2334              // AIX OS team come up with a good solution.
2335              .Case("llvm.used", true)
2336              // It's correct to just skip llvm.compiler.used array here.
2337              .Case("llvm.compiler.used", true)
2338              .Default(false);
2339 }
2340 
2341 static bool isSpecialLLVMGlobalArrayForStaticInit(const GlobalVariable *GV) {
2342   return StringSwitch<bool>(GV->getName())
2343       .Cases("llvm.global_ctors", "llvm.global_dtors", true)
2344       .Default(false);
2345 }
2346 
2347 void PPCAIXAsmPrinter::emitGlobalVariable(const GlobalVariable *GV) {
2348   // Special LLVM global arrays have been handled at the initialization.
2349   if (isSpecialLLVMGlobalArrayToSkip(GV) || isSpecialLLVMGlobalArrayForStaticInit(GV))
2350     return;
2351 
2352   // If the Global Variable has the toc-data attribute, it needs to be emitted
2353   // when we emit the .toc section.
2354   if (GV->hasAttribute("toc-data")) {
2355     TOCDataGlobalVars.push_back(GV);
2356     return;
2357   }
2358 
2359   emitGlobalVariableHelper(GV);
2360 }
2361 
2362 void PPCAIXAsmPrinter::emitGlobalVariableHelper(const GlobalVariable *GV) {
2363   assert(!GV->getName().startswith("llvm.") &&
2364          "Unhandled intrinsic global variable.");
2365 
2366   if (GV->hasComdat())
2367     report_fatal_error("COMDAT not yet supported by AIX.");
2368 
2369   MCSymbolXCOFF *GVSym = cast<MCSymbolXCOFF>(getSymbol(GV));
2370 
2371   if (GV->isDeclarationForLinker()) {
2372     emitLinkage(GV, GVSym);
2373     return;
2374   }
2375 
2376   SectionKind GVKind = getObjFileLowering().getKindForGlobal(GV, TM);
2377   if (!GVKind.isGlobalWriteableData() && !GVKind.isReadOnly() &&
2378       !GVKind.isThreadLocal()) // Checks for both ThreadData and ThreadBSS.
2379     report_fatal_error("Encountered a global variable kind that is "
2380                        "not supported yet.");
2381 
2382   // Print GV in verbose mode
2383   if (isVerbose()) {
2384     if (GV->hasInitializer()) {
2385       GV->printAsOperand(OutStreamer->GetCommentOS(),
2386                          /*PrintType=*/false, GV->getParent());
2387       OutStreamer->GetCommentOS() << '\n';
2388     }
2389   }
2390 
2391   MCSectionXCOFF *Csect = cast<MCSectionXCOFF>(
2392       getObjFileLowering().SectionForGlobal(GV, GVKind, TM));
2393 
2394   // Switch to the containing csect.
2395   OutStreamer->SwitchSection(Csect);
2396 
2397   const DataLayout &DL = GV->getParent()->getDataLayout();
2398 
2399   // Handle common and zero-initialized local symbols.
2400   if (GV->hasCommonLinkage() || GVKind.isBSSLocal() ||
2401       GVKind.isThreadBSSLocal()) {
2402     Align Alignment = GV->getAlign().getValueOr(DL.getPreferredAlign(GV));
2403     uint64_t Size = DL.getTypeAllocSize(GV->getValueType());
2404     GVSym->setStorageClass(
2405         TargetLoweringObjectFileXCOFF::getStorageClassForGlobal(GV));
2406 
2407     if (GVKind.isBSSLocal() || GVKind.isThreadBSSLocal())
2408       OutStreamer->emitXCOFFLocalCommonSymbol(
2409           OutContext.getOrCreateSymbol(GVSym->getSymbolTableName()), Size,
2410           GVSym, Alignment.value());
2411     else
2412       OutStreamer->emitCommonSymbol(GVSym, Size, Alignment.value());
2413     return;
2414   }
2415 
2416   MCSymbol *EmittedInitSym = GVSym;
2417   emitLinkage(GV, EmittedInitSym);
2418   emitAlignment(getGVAlignment(GV, DL), GV);
2419 
2420   // When -fdata-sections is enabled, every GlobalVariable will
2421   // be put into its own csect; therefore, label is not necessary here.
2422   if (!TM.getDataSections() || GV->hasSection()) {
2423     OutStreamer->emitLabel(EmittedInitSym);
2424   }
2425 
2426   // Emit aliasing label for global variable.
2427   llvm::for_each(GOAliasMap[GV], [this](const GlobalAlias *Alias) {
2428     OutStreamer->emitLabel(getSymbol(Alias));
2429   });
2430 
2431   emitGlobalConstant(GV->getParent()->getDataLayout(), GV->getInitializer());
2432 }
2433 
2434 void PPCAIXAsmPrinter::emitFunctionDescriptor() {
2435   const DataLayout &DL = getDataLayout();
2436   const unsigned PointerSize = DL.getPointerSizeInBits() == 64 ? 8 : 4;
2437 
2438   MCSectionSubPair Current = OutStreamer->getCurrentSection();
2439   // Emit function descriptor.
2440   OutStreamer->SwitchSection(
2441       cast<MCSymbolXCOFF>(CurrentFnDescSym)->getRepresentedCsect());
2442 
2443   // Emit aliasing label for function descriptor csect.
2444   llvm::for_each(GOAliasMap[&MF->getFunction()],
2445                  [this](const GlobalAlias *Alias) {
2446                    OutStreamer->emitLabel(getSymbol(Alias));
2447                  });
2448 
2449   // Emit function entry point address.
2450   OutStreamer->emitValue(MCSymbolRefExpr::create(CurrentFnSym, OutContext),
2451                          PointerSize);
2452   // Emit TOC base address.
2453   const MCSymbol *TOCBaseSym =
2454       cast<MCSectionXCOFF>(getObjFileLowering().getTOCBaseSection())
2455           ->getQualNameSymbol();
2456   OutStreamer->emitValue(MCSymbolRefExpr::create(TOCBaseSym, OutContext),
2457                          PointerSize);
2458   // Emit a null environment pointer.
2459   OutStreamer->emitIntValue(0, PointerSize);
2460 
2461   OutStreamer->SwitchSection(Current.first, Current.second);
2462 }
2463 
2464 void PPCAIXAsmPrinter::emitFunctionEntryLabel() {
2465   // It's not necessary to emit the label when we have individual
2466   // function in its own csect.
2467   if (!TM.getFunctionSections())
2468     PPCAsmPrinter::emitFunctionEntryLabel();
2469 
2470   // Emit aliasing label for function entry point label.
2471   llvm::for_each(
2472       GOAliasMap[&MF->getFunction()], [this](const GlobalAlias *Alias) {
2473         OutStreamer->emitLabel(
2474             getObjFileLowering().getFunctionEntryPointSymbol(Alias, TM));
2475       });
2476 }
2477 
2478 void PPCAIXAsmPrinter::emitEndOfAsmFile(Module &M) {
2479   // If there are no functions and there are no toc-data definitions in this
2480   // module, we will never need to reference the TOC base.
2481   if (M.empty() && TOCDataGlobalVars.empty())
2482     return;
2483 
2484   // Switch to section to emit TOC base.
2485   OutStreamer->SwitchSection(getObjFileLowering().getTOCBaseSection());
2486 
2487   PPCTargetStreamer *TS =
2488       static_cast<PPCTargetStreamer *>(OutStreamer->getTargetStreamer());
2489 
2490   for (auto &I : TOC) {
2491     MCSectionXCOFF *TCEntry;
2492     // Setup the csect for the current TC entry. If the variant kind is
2493     // VK_PPC_AIX_TLSGDM the entry represents the region handle, we create a
2494     // new symbol to prefix the name with a dot.
2495     if (I.first.second == MCSymbolRefExpr::VariantKind::VK_PPC_AIX_TLSGDM) {
2496       SmallString<128> Name;
2497       StringRef Prefix = ".";
2498       Name += Prefix;
2499       Name += I.first.first->getName();
2500       MCSymbol *S = OutContext.getOrCreateSymbol(Name);
2501       TCEntry = cast<MCSectionXCOFF>(
2502           getObjFileLowering().getSectionForTOCEntry(S, TM));
2503     } else {
2504       TCEntry = cast<MCSectionXCOFF>(
2505           getObjFileLowering().getSectionForTOCEntry(I.first.first, TM));
2506     }
2507     OutStreamer->SwitchSection(TCEntry);
2508 
2509     OutStreamer->emitLabel(I.second);
2510     if (TS != nullptr)
2511       TS->emitTCEntry(*I.first.first, I.first.second);
2512   }
2513 
2514   for (const auto *GV : TOCDataGlobalVars)
2515     emitGlobalVariableHelper(GV);
2516 }
2517 
2518 bool PPCAIXAsmPrinter::doInitialization(Module &M) {
2519   const bool Result = PPCAsmPrinter::doInitialization(M);
2520 
2521   auto setCsectAlignment = [this](const GlobalObject *GO) {
2522     // Declarations have 0 alignment which is set by default.
2523     if (GO->isDeclarationForLinker())
2524       return;
2525 
2526     SectionKind GOKind = getObjFileLowering().getKindForGlobal(GO, TM);
2527     MCSectionXCOFF *Csect = cast<MCSectionXCOFF>(
2528         getObjFileLowering().SectionForGlobal(GO, GOKind, TM));
2529 
2530     Align GOAlign = getGVAlignment(GO, GO->getParent()->getDataLayout());
2531     if (GOAlign > Csect->getAlignment())
2532       Csect->setAlignment(GOAlign);
2533   };
2534 
2535   // We need to know, up front, the alignment of csects for the assembly path,
2536   // because once a .csect directive gets emitted, we could not change the
2537   // alignment value on it.
2538   for (const auto &G : M.globals()) {
2539     if (isSpecialLLVMGlobalArrayToSkip(&G))
2540       continue;
2541 
2542     if (isSpecialLLVMGlobalArrayForStaticInit(&G)) {
2543       // Generate a format indicator and a unique module id to be a part of
2544       // the sinit and sterm function names.
2545       if (FormatIndicatorAndUniqueModId.empty()) {
2546         std::string UniqueModuleId = getUniqueModuleId(&M);
2547         if (UniqueModuleId != "")
2548           // TODO: Use source file full path to generate the unique module id
2549           // and add a format indicator as a part of function name in case we
2550           // will support more than one format.
2551           FormatIndicatorAndUniqueModId = "clang_" + UniqueModuleId.substr(1);
2552         else
2553           // Use the Pid and current time as the unique module id when we cannot
2554           // generate one based on a module's strong external symbols.
2555           // FIXME: Adjust the comment accordingly after we use source file full
2556           // path instead.
2557           FormatIndicatorAndUniqueModId =
2558               "clangPidTime_" + llvm::itostr(sys::Process::getProcessId()) +
2559               "_" + llvm::itostr(time(nullptr));
2560       }
2561 
2562       emitSpecialLLVMGlobal(&G);
2563       continue;
2564     }
2565 
2566     setCsectAlignment(&G);
2567   }
2568 
2569   for (const auto &F : M)
2570     setCsectAlignment(&F);
2571 
2572   // Construct an aliasing list for each GlobalObject.
2573   for (const auto &Alias : M.aliases()) {
2574     const GlobalObject *Base = Alias.getAliaseeObject();
2575     if (!Base)
2576       report_fatal_error(
2577           "alias without a base object is not yet supported on AIX");
2578     GOAliasMap[Base].push_back(&Alias);
2579   }
2580 
2581   return Result;
2582 }
2583 
2584 void PPCAIXAsmPrinter::emitInstruction(const MachineInstr *MI) {
2585   switch (MI->getOpcode()) {
2586   default:
2587     break;
2588   case PPC::GETtlsADDR64AIX:
2589   case PPC::GETtlsADDR32AIX: {
2590     // The reference to .__tls_get_addr is unknown to the assembler
2591     // so we need to emit an external symbol reference.
2592     MCSymbol *TlsGetAddr = createMCSymbolForTlsGetAddr(OutContext);
2593     ExtSymSDNodeSymbols.insert(TlsGetAddr);
2594     break;
2595   }
2596   case PPC::BL8:
2597   case PPC::BL:
2598   case PPC::BL8_NOP:
2599   case PPC::BL_NOP: {
2600     const MachineOperand &MO = MI->getOperand(0);
2601     if (MO.isSymbol()) {
2602       MCSymbolXCOFF *S =
2603           cast<MCSymbolXCOFF>(OutContext.getOrCreateSymbol(MO.getSymbolName()));
2604       ExtSymSDNodeSymbols.insert(S);
2605     }
2606   } break;
2607   case PPC::BL_TLS:
2608   case PPC::BL8_TLS:
2609   case PPC::BL8_TLS_:
2610   case PPC::BL8_NOP_TLS:
2611     report_fatal_error("TLS call not yet implemented");
2612   case PPC::TAILB:
2613   case PPC::TAILB8:
2614   case PPC::TAILBA:
2615   case PPC::TAILBA8:
2616   case PPC::TAILBCTR:
2617   case PPC::TAILBCTR8:
2618     if (MI->getOperand(0).isSymbol())
2619       report_fatal_error("Tail call for extern symbol not yet supported.");
2620     break;
2621   case PPC::DST:
2622   case PPC::DST64:
2623   case PPC::DSTT:
2624   case PPC::DSTT64:
2625   case PPC::DSTST:
2626   case PPC::DSTST64:
2627   case PPC::DSTSTT:
2628   case PPC::DSTSTT64:
2629     EmitToStreamer(
2630         *OutStreamer,
2631         MCInstBuilder(PPC::ORI).addReg(PPC::R0).addReg(PPC::R0).addImm(0));
2632     return;
2633   }
2634   return PPCAsmPrinter::emitInstruction(MI);
2635 }
2636 
2637 bool PPCAIXAsmPrinter::doFinalization(Module &M) {
2638   // Do streamer related finalization for DWARF.
2639   if (!MAI->usesDwarfFileAndLocDirectives() && MMI->hasDebugInfo())
2640     OutStreamer->doFinalizationAtSectionEnd(
2641         OutStreamer->getContext().getObjectFileInfo()->getTextSection());
2642 
2643   for (MCSymbol *Sym : ExtSymSDNodeSymbols)
2644     OutStreamer->emitSymbolAttribute(Sym, MCSA_Extern);
2645   return PPCAsmPrinter::doFinalization(M);
2646 }
2647 
2648 static unsigned mapToSinitPriority(int P) {
2649   if (P < 0 || P > 65535)
2650     report_fatal_error("invalid init priority");
2651 
2652   if (P <= 20)
2653     return P;
2654 
2655   if (P < 81)
2656     return 20 + (P - 20) * 16;
2657 
2658   if (P <= 1124)
2659     return 1004 + (P - 81);
2660 
2661   if (P < 64512)
2662     return 2047 + (P - 1124) * 33878;
2663 
2664   return 2147482625u + (P - 64512);
2665 }
2666 
2667 static std::string convertToSinitPriority(int Priority) {
2668   // This helper function converts clang init priority to values used in sinit
2669   // and sterm functions.
2670   //
2671   // The conversion strategies are:
2672   // We map the reserved clang/gnu priority range [0, 100] into the sinit/sterm
2673   // reserved priority range [0, 1023] by
2674   // - directly mapping the first 21 and the last 20 elements of the ranges
2675   // - linear interpolating the intermediate values with a step size of 16.
2676   //
2677   // We map the non reserved clang/gnu priority range of [101, 65535] into the
2678   // sinit/sterm priority range [1024, 2147483648] by:
2679   // - directly mapping the first and the last 1024 elements of the ranges
2680   // - linear interpolating the intermediate values with a step size of 33878.
2681   unsigned int P = mapToSinitPriority(Priority);
2682 
2683   std::string PrioritySuffix;
2684   llvm::raw_string_ostream os(PrioritySuffix);
2685   os << llvm::format_hex_no_prefix(P, 8);
2686   os.flush();
2687   return PrioritySuffix;
2688 }
2689 
2690 void PPCAIXAsmPrinter::emitXXStructorList(const DataLayout &DL,
2691                                           const Constant *List, bool IsCtor) {
2692   SmallVector<Structor, 8> Structors;
2693   preprocessXXStructorList(DL, List, Structors);
2694   if (Structors.empty())
2695     return;
2696 
2697   unsigned Index = 0;
2698   for (Structor &S : Structors) {
2699     if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(S.Func))
2700       S.Func = CE->getOperand(0);
2701 
2702     llvm::GlobalAlias::create(
2703         GlobalValue::ExternalLinkage,
2704         (IsCtor ? llvm::Twine("__sinit") : llvm::Twine("__sterm")) +
2705             llvm::Twine(convertToSinitPriority(S.Priority)) +
2706             llvm::Twine("_", FormatIndicatorAndUniqueModId) +
2707             llvm::Twine("_", llvm::utostr(Index++)),
2708         cast<Function>(S.Func));
2709   }
2710 }
2711 
2712 void PPCAIXAsmPrinter::emitTTypeReference(const GlobalValue *GV,
2713                                           unsigned Encoding) {
2714   if (GV) {
2715     MCSymbol *TypeInfoSym = TM.getSymbol(GV);
2716     MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(TypeInfoSym);
2717     const MCSymbol *TOCBaseSym =
2718         cast<MCSectionXCOFF>(getObjFileLowering().getTOCBaseSection())
2719             ->getQualNameSymbol();
2720     auto &Ctx = OutStreamer->getContext();
2721     const MCExpr *Exp =
2722         MCBinaryExpr::createSub(MCSymbolRefExpr::create(TOCEntry, Ctx),
2723                                 MCSymbolRefExpr::create(TOCBaseSym, Ctx), Ctx);
2724     OutStreamer->emitValue(Exp, GetSizeOfEncodedValue(Encoding));
2725   } else
2726     OutStreamer->emitIntValue(0, GetSizeOfEncodedValue(Encoding));
2727 }
2728 
2729 // Return a pass that prints the PPC assembly code for a MachineFunction to the
2730 // given output stream.
2731 static AsmPrinter *
2732 createPPCAsmPrinterPass(TargetMachine &tm,
2733                         std::unique_ptr<MCStreamer> &&Streamer) {
2734   if (tm.getTargetTriple().isOSAIX())
2735     return new PPCAIXAsmPrinter(tm, std::move(Streamer));
2736 
2737   return new PPCLinuxAsmPrinter(tm, std::move(Streamer));
2738 }
2739 
2740 // Force static initialization.
2741 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCAsmPrinter() {
2742   TargetRegistry::RegisterAsmPrinter(getThePPC32Target(),
2743                                      createPPCAsmPrinterPass);
2744   TargetRegistry::RegisterAsmPrinter(getThePPC32LETarget(),
2745                                      createPPCAsmPrinterPass);
2746   TargetRegistry::RegisterAsmPrinter(getThePPC64Target(),
2747                                      createPPCAsmPrinterPass);
2748   TargetRegistry::RegisterAsmPrinter(getThePPC64LETarget(),
2749                                      createPPCAsmPrinterPass);
2750 }
2751