1 //===- AArch64AsmPrinter.cpp - AArch64 LLVM assembly writer ---------------===//
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 the AArch64 assembly language.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "AArch64.h"
15 #include "AArch64MCInstLower.h"
16 #include "AArch64MachineFunctionInfo.h"
17 #include "AArch64RegisterInfo.h"
18 #include "AArch64Subtarget.h"
19 #include "AArch64TargetObjectFile.h"
20 #include "MCTargetDesc/AArch64AddressingModes.h"
21 #include "MCTargetDesc/AArch64InstPrinter.h"
22 #include "MCTargetDesc/AArch64MCExpr.h"
23 #include "MCTargetDesc/AArch64MCTargetDesc.h"
24 #include "MCTargetDesc/AArch64TargetStreamer.h"
25 #include "TargetInfo/AArch64TargetInfo.h"
26 #include "Utils/AArch64BaseInfo.h"
27 #include "llvm/ADT/SmallString.h"
28 #include "llvm/ADT/SmallVector.h"
29 #include "llvm/ADT/StringRef.h"
30 #include "llvm/ADT/Triple.h"
31 #include "llvm/ADT/Twine.h"
32 #include "llvm/BinaryFormat/COFF.h"
33 #include "llvm/BinaryFormat/ELF.h"
34 #include "llvm/CodeGen/AsmPrinter.h"
35 #include "llvm/CodeGen/FaultMaps.h"
36 #include "llvm/CodeGen/MachineBasicBlock.h"
37 #include "llvm/CodeGen/MachineFunction.h"
38 #include "llvm/CodeGen/MachineInstr.h"
39 #include "llvm/CodeGen/MachineJumpTableInfo.h"
40 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
41 #include "llvm/CodeGen/MachineOperand.h"
42 #include "llvm/CodeGen/StackMaps.h"
43 #include "llvm/CodeGen/TargetRegisterInfo.h"
44 #include "llvm/IR/DataLayout.h"
45 #include "llvm/IR/DebugInfoMetadata.h"
46 #include "llvm/MC/MCAsmInfo.h"
47 #include "llvm/MC/MCContext.h"
48 #include "llvm/MC/MCInst.h"
49 #include "llvm/MC/MCInstBuilder.h"
50 #include "llvm/MC/MCSectionELF.h"
51 #include "llvm/MC/MCStreamer.h"
52 #include "llvm/MC/MCSymbol.h"
53 #include "llvm/MC/TargetRegistry.h"
54 #include "llvm/Support/Casting.h"
55 #include "llvm/Support/ErrorHandling.h"
56 #include "llvm/Support/raw_ostream.h"
57 #include "llvm/Target/TargetMachine.h"
58 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
59 #include <algorithm>
60 #include <cassert>
61 #include <cstdint>
62 #include <map>
63 #include <memory>
64 
65 using namespace llvm;
66 
67 #define DEBUG_TYPE "asm-printer"
68 
69 namespace {
70 
71 class AArch64AsmPrinter : public AsmPrinter {
72   AArch64MCInstLower MCInstLowering;
73   FaultMaps FM;
74   const AArch64Subtarget *STI;
75   bool ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags = false;
76 
77 public:
78   AArch64AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer)
79       : AsmPrinter(TM, std::move(Streamer)), MCInstLowering(OutContext, *this),
80         FM(*this) {}
81 
82   StringRef getPassName() const override { return "AArch64 Assembly Printer"; }
83 
84   /// Wrapper for MCInstLowering.lowerOperand() for the
85   /// tblgen'erated pseudo lowering.
86   bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp) const {
87     return MCInstLowering.lowerOperand(MO, MCOp);
88   }
89 
90   void emitStartOfAsmFile(Module &M) override;
91   void emitJumpTableInfo() override;
92 
93   void emitFunctionEntryLabel() override;
94 
95   void LowerJumpTableDest(MCStreamer &OutStreamer, const MachineInstr &MI);
96 
97   void LowerMOPS(MCStreamer &OutStreamer, const MachineInstr &MI);
98 
99   void LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM,
100                      const MachineInstr &MI);
101   void LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM,
102                        const MachineInstr &MI);
103   void LowerSTATEPOINT(MCStreamer &OutStreamer, StackMaps &SM,
104                        const MachineInstr &MI);
105   void LowerFAULTING_OP(const MachineInstr &MI);
106 
107   void LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI);
108   void LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI);
109   void LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI);
110 
111   typedef std::tuple<unsigned, bool, uint32_t> HwasanMemaccessTuple;
112   std::map<HwasanMemaccessTuple, MCSymbol *> HwasanMemaccessSymbols;
113   void LowerKCFI_CHECK(const MachineInstr &MI);
114   void LowerHWASAN_CHECK_MEMACCESS(const MachineInstr &MI);
115   void emitHwasanMemaccessSymbols(Module &M);
116 
117   void emitSled(const MachineInstr &MI, SledKind Kind);
118 
119   /// tblgen'erated driver function for lowering simple MI->MC
120   /// pseudo instructions.
121   bool emitPseudoExpansionLowering(MCStreamer &OutStreamer,
122                                    const MachineInstr *MI);
123 
124   void emitInstruction(const MachineInstr *MI) override;
125 
126   void emitFunctionHeaderComment() override;
127 
128   void getAnalysisUsage(AnalysisUsage &AU) const override {
129     AsmPrinter::getAnalysisUsage(AU);
130     AU.setPreservesAll();
131   }
132 
133   bool runOnMachineFunction(MachineFunction &MF) override {
134     AArch64FI = MF.getInfo<AArch64FunctionInfo>();
135     STI = &MF.getSubtarget<AArch64Subtarget>();
136 
137     SetupMachineFunction(MF);
138 
139     if (STI->isTargetCOFF()) {
140       bool Internal = MF.getFunction().hasInternalLinkage();
141       COFF::SymbolStorageClass Scl = Internal ? COFF::IMAGE_SYM_CLASS_STATIC
142                                               : COFF::IMAGE_SYM_CLASS_EXTERNAL;
143       int Type =
144         COFF::IMAGE_SYM_DTYPE_FUNCTION << COFF::SCT_COMPLEX_TYPE_SHIFT;
145 
146       OutStreamer->beginCOFFSymbolDef(CurrentFnSym);
147       OutStreamer->emitCOFFSymbolStorageClass(Scl);
148       OutStreamer->emitCOFFSymbolType(Type);
149       OutStreamer->endCOFFSymbolDef();
150     }
151 
152     // Emit the rest of the function body.
153     emitFunctionBody();
154 
155     // Emit the XRay table for this function.
156     emitXRayTable();
157 
158     // We didn't modify anything.
159     return false;
160   }
161 
162 private:
163   void printOperand(const MachineInstr *MI, unsigned OpNum, raw_ostream &O);
164   bool printAsmMRegister(const MachineOperand &MO, char Mode, raw_ostream &O);
165   bool printAsmRegInClass(const MachineOperand &MO,
166                           const TargetRegisterClass *RC, unsigned AltName,
167                           raw_ostream &O);
168 
169   bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
170                        const char *ExtraCode, raw_ostream &O) override;
171   bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
172                              const char *ExtraCode, raw_ostream &O) override;
173 
174   void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
175 
176   void emitFunctionBodyEnd() override;
177 
178   MCSymbol *GetCPISymbol(unsigned CPID) const override;
179   void emitEndOfAsmFile(Module &M) override;
180 
181   AArch64FunctionInfo *AArch64FI = nullptr;
182 
183   /// Emit the LOHs contained in AArch64FI.
184   void emitLOHs();
185 
186   /// Emit instruction to set float register to zero.
187   void emitFMov0(const MachineInstr &MI);
188 
189   using MInstToMCSymbol = std::map<const MachineInstr *, MCSymbol *>;
190 
191   MInstToMCSymbol LOHInstToLabel;
192 
193   bool shouldEmitWeakSwiftAsyncExtendedFramePointerFlags() const override {
194     return ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags;
195   }
196 };
197 
198 } // end anonymous namespace
199 
200 void AArch64AsmPrinter::emitStartOfAsmFile(Module &M) {
201   const Triple &TT = TM.getTargetTriple();
202 
203   if (TT.isOSBinFormatCOFF()) {
204     // Emit an absolute @feat.00 symbol
205     MCSymbol *S = MMI->getContext().getOrCreateSymbol(StringRef("@feat.00"));
206     OutStreamer->beginCOFFSymbolDef(S);
207     OutStreamer->emitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_STATIC);
208     OutStreamer->emitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_NULL);
209     OutStreamer->endCOFFSymbolDef();
210     int64_t Feat00Value = 0;
211 
212     if (M.getModuleFlag("cfguard")) {
213       // Object is CFG-aware.
214       Feat00Value |= COFF::Feat00Flags::GuardCF;
215     }
216 
217     if (M.getModuleFlag("ehcontguard")) {
218       // Object also has EHCont.
219       Feat00Value |= COFF::Feat00Flags::GuardEHCont;
220     }
221 
222     if (M.getModuleFlag("ms-kernel")) {
223       // Object is compiled with /kernel.
224       Feat00Value |= COFF::Feat00Flags::Kernel;
225     }
226 
227     OutStreamer->emitSymbolAttribute(S, MCSA_Global);
228     OutStreamer->emitAssignment(
229         S, MCConstantExpr::create(Feat00Value, MMI->getContext()));
230   }
231 
232   if (!TT.isOSBinFormatELF())
233     return;
234 
235   // Assemble feature flags that may require creation of a note section.
236   unsigned Flags = 0;
237   if (const auto *BTE = mdconst::extract_or_null<ConstantInt>(
238           M.getModuleFlag("branch-target-enforcement")))
239     if (BTE->getZExtValue())
240       Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
241 
242   if (const auto *Sign = mdconst::extract_or_null<ConstantInt>(
243           M.getModuleFlag("sign-return-address")))
244     if (Sign->getZExtValue())
245       Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_PAC;
246 
247   if (Flags == 0)
248     return;
249 
250   // Emit a .note.gnu.property section with the flags.
251   auto *TS =
252       static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
253   TS->emitNoteSection(Flags);
254 }
255 
256 void AArch64AsmPrinter::emitFunctionHeaderComment() {
257   const AArch64FunctionInfo *FI = MF->getInfo<AArch64FunctionInfo>();
258   std::optional<std::string> OutlinerString = FI->getOutliningStyle();
259   if (OutlinerString != std::nullopt)
260     OutStreamer->getCommentOS() << ' ' << OutlinerString;
261 }
262 
263 void AArch64AsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI)
264 {
265   const Function &F = MF->getFunction();
266   if (F.hasFnAttribute("patchable-function-entry")) {
267     unsigned Num;
268     if (F.getFnAttribute("patchable-function-entry")
269             .getValueAsString()
270             .getAsInteger(10, Num))
271       return;
272     emitNops(Num);
273     return;
274   }
275 
276   emitSled(MI, SledKind::FUNCTION_ENTER);
277 }
278 
279 void AArch64AsmPrinter::LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI) {
280   emitSled(MI, SledKind::FUNCTION_EXIT);
281 }
282 
283 void AArch64AsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI) {
284   emitSled(MI, SledKind::TAIL_CALL);
285 }
286 
287 void AArch64AsmPrinter::emitSled(const MachineInstr &MI, SledKind Kind) {
288   static const int8_t NoopsInSledCount = 7;
289   // We want to emit the following pattern:
290   //
291   // .Lxray_sled_N:
292   //   ALIGN
293   //   B #32
294   //   ; 7 NOP instructions (28 bytes)
295   // .tmpN
296   //
297   // We need the 28 bytes (7 instructions) because at runtime, we'd be patching
298   // over the full 32 bytes (8 instructions) with the following pattern:
299   //
300   //   STP X0, X30, [SP, #-16]! ; push X0 and the link register to the stack
301   //   LDR W0, #12 ; W0 := function ID
302   //   LDR X16,#12 ; X16 := addr of __xray_FunctionEntry or __xray_FunctionExit
303   //   BLR X16 ; call the tracing trampoline
304   //   ;DATA: 32 bits of function ID
305   //   ;DATA: lower 32 bits of the address of the trampoline
306   //   ;DATA: higher 32 bits of the address of the trampoline
307   //   LDP X0, X30, [SP], #16 ; pop X0 and the link register from the stack
308   //
309   OutStreamer->emitCodeAlignment(Align(4), &getSubtargetInfo());
310   auto CurSled = OutContext.createTempSymbol("xray_sled_", true);
311   OutStreamer->emitLabel(CurSled);
312   auto Target = OutContext.createTempSymbol();
313 
314   // Emit "B #32" instruction, which jumps over the next 28 bytes.
315   // The operand has to be the number of 4-byte instructions to jump over,
316   // including the current instruction.
317   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::B).addImm(8));
318 
319   for (int8_t I = 0; I < NoopsInSledCount; I++)
320     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
321 
322   OutStreamer->emitLabel(Target);
323   recordSled(CurSled, MI, Kind, 2);
324 }
325 
326 void AArch64AsmPrinter::LowerKCFI_CHECK(const MachineInstr &MI) {
327   Register AddrReg = MI.getOperand(0).getReg();
328   assert(std::next(MI.getIterator())->isCall() &&
329          "KCFI_CHECK not followed by a call instruction");
330   assert(std::next(MI.getIterator())->getOperand(0).getReg() == AddrReg &&
331          "KCFI_CHECK call target doesn't match call operand");
332 
333   // Default to using the intra-procedure-call temporary registers for
334   // comparing the hashes.
335   unsigned ScratchRegs[] = {AArch64::W16, AArch64::W17};
336   if (AddrReg == AArch64::XZR) {
337     // Checking XZR makes no sense. Instead of emitting a load, zero
338     // ScratchRegs[0] and use it for the ESR AddrIndex below.
339     AddrReg = getXRegFromWReg(ScratchRegs[0]);
340     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::ORRXrs)
341                                      .addReg(AddrReg)
342                                      .addReg(AArch64::XZR)
343                                      .addReg(AArch64::XZR)
344                                      .addImm(0));
345   } else {
346     // If one of the scratch registers is used for the call target (e.g.
347     // with AArch64::TCRETURNriBTI), we can clobber another caller-saved
348     // temporary register instead (in this case, AArch64::W9) as the check
349     // is immediately followed by the call instruction.
350     for (auto &Reg : ScratchRegs) {
351       if (Reg == getWRegFromXReg(AddrReg)) {
352         Reg = AArch64::W9;
353         break;
354       }
355     }
356     assert(ScratchRegs[0] != AddrReg && ScratchRegs[1] != AddrReg &&
357            "Invalid scratch registers for KCFI_CHECK");
358 
359     // Adjust the offset for patchable-function-prefix. This assumes that
360     // patchable-function-prefix is the same for all functions.
361     int64_t PrefixNops = 0;
362     (void)MI.getMF()
363         ->getFunction()
364         .getFnAttribute("patchable-function-prefix")
365         .getValueAsString()
366         .getAsInteger(10, PrefixNops);
367 
368     // Load the target function type hash.
369     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::LDURWi)
370                                      .addReg(ScratchRegs[0])
371                                      .addReg(AddrReg)
372                                      .addImm(-(PrefixNops * 4 + 4)));
373   }
374 
375   // Load the expected type hash.
376   const int64_t Type = MI.getOperand(1).getImm();
377   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::MOVKWi)
378                                    .addReg(ScratchRegs[1])
379                                    .addReg(ScratchRegs[1])
380                                    .addImm(Type & 0xFFFF)
381                                    .addImm(0));
382   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::MOVKWi)
383                                    .addReg(ScratchRegs[1])
384                                    .addReg(ScratchRegs[1])
385                                    .addImm((Type >> 16) & 0xFFFF)
386                                    .addImm(16));
387 
388   // Compare the hashes and trap if there's a mismatch.
389   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::SUBSWrs)
390                                    .addReg(AArch64::WZR)
391                                    .addReg(ScratchRegs[0])
392                                    .addReg(ScratchRegs[1])
393                                    .addImm(0));
394 
395   MCSymbol *Pass = OutContext.createTempSymbol();
396   EmitToStreamer(*OutStreamer,
397                  MCInstBuilder(AArch64::Bcc)
398                      .addImm(AArch64CC::EQ)
399                      .addExpr(MCSymbolRefExpr::create(Pass, OutContext)));
400 
401   // The base ESR is 0x8000 and the register information is encoded in bits
402   // 0-9 as follows:
403   // - 0-4: n, where the register Xn contains the target address
404   // - 5-9: m, where the register Wm contains the expected type hash
405   // Where n, m are in [0, 30].
406   unsigned TypeIndex = ScratchRegs[1] - AArch64::W0;
407   unsigned AddrIndex;
408   switch (AddrReg) {
409   default:
410     AddrIndex = AddrReg - AArch64::X0;
411     break;
412   case AArch64::FP:
413     AddrIndex = 29;
414     break;
415   case AArch64::LR:
416     AddrIndex = 30;
417     break;
418   }
419 
420   assert(AddrIndex < 31 && TypeIndex < 31);
421 
422   unsigned ESR = 0x8000 | ((TypeIndex & 31) << 5) | (AddrIndex & 31);
423   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::BRK).addImm(ESR));
424   OutStreamer->emitLabel(Pass);
425 }
426 
427 void AArch64AsmPrinter::LowerHWASAN_CHECK_MEMACCESS(const MachineInstr &MI) {
428   Register Reg = MI.getOperand(0).getReg();
429   bool IsShort =
430       MI.getOpcode() == AArch64::HWASAN_CHECK_MEMACCESS_SHORTGRANULES;
431   uint32_t AccessInfo = MI.getOperand(1).getImm();
432   MCSymbol *&Sym =
433       HwasanMemaccessSymbols[HwasanMemaccessTuple(Reg, IsShort, AccessInfo)];
434   if (!Sym) {
435     // FIXME: Make this work on non-ELF.
436     if (!TM.getTargetTriple().isOSBinFormatELF())
437       report_fatal_error("llvm.hwasan.check.memaccess only supported on ELF");
438 
439     std::string SymName = "__hwasan_check_x" + utostr(Reg - AArch64::X0) + "_" +
440                           utostr(AccessInfo);
441     if (IsShort)
442       SymName += "_short_v2";
443     Sym = OutContext.getOrCreateSymbol(SymName);
444   }
445 
446   EmitToStreamer(*OutStreamer,
447                  MCInstBuilder(AArch64::BL)
448                      .addExpr(MCSymbolRefExpr::create(Sym, OutContext)));
449 }
450 
451 void AArch64AsmPrinter::emitHwasanMemaccessSymbols(Module &M) {
452   if (HwasanMemaccessSymbols.empty())
453     return;
454 
455   const Triple &TT = TM.getTargetTriple();
456   assert(TT.isOSBinFormatELF());
457   std::unique_ptr<MCSubtargetInfo> STI(
458       TM.getTarget().createMCSubtargetInfo(TT.str(), "", ""));
459   assert(STI && "Unable to create subtarget info");
460 
461   MCSymbol *HwasanTagMismatchV1Sym =
462       OutContext.getOrCreateSymbol("__hwasan_tag_mismatch");
463   MCSymbol *HwasanTagMismatchV2Sym =
464       OutContext.getOrCreateSymbol("__hwasan_tag_mismatch_v2");
465 
466   const MCSymbolRefExpr *HwasanTagMismatchV1Ref =
467       MCSymbolRefExpr::create(HwasanTagMismatchV1Sym, OutContext);
468   const MCSymbolRefExpr *HwasanTagMismatchV2Ref =
469       MCSymbolRefExpr::create(HwasanTagMismatchV2Sym, OutContext);
470 
471   for (auto &P : HwasanMemaccessSymbols) {
472     unsigned Reg = std::get<0>(P.first);
473     bool IsShort = std::get<1>(P.first);
474     uint32_t AccessInfo = std::get<2>(P.first);
475     const MCSymbolRefExpr *HwasanTagMismatchRef =
476         IsShort ? HwasanTagMismatchV2Ref : HwasanTagMismatchV1Ref;
477     MCSymbol *Sym = P.second;
478 
479     bool HasMatchAllTag =
480         (AccessInfo >> HWASanAccessInfo::HasMatchAllShift) & 1;
481     uint8_t MatchAllTag =
482         (AccessInfo >> HWASanAccessInfo::MatchAllShift) & 0xff;
483     unsigned Size =
484         1 << ((AccessInfo >> HWASanAccessInfo::AccessSizeShift) & 0xf);
485     bool CompileKernel =
486         (AccessInfo >> HWASanAccessInfo::CompileKernelShift) & 1;
487 
488     OutStreamer->switchSection(OutContext.getELFSection(
489         ".text.hot", ELF::SHT_PROGBITS,
490         ELF::SHF_EXECINSTR | ELF::SHF_ALLOC | ELF::SHF_GROUP, 0, Sym->getName(),
491         /*IsComdat=*/true));
492 
493     OutStreamer->emitSymbolAttribute(Sym, MCSA_ELF_TypeFunction);
494     OutStreamer->emitSymbolAttribute(Sym, MCSA_Weak);
495     OutStreamer->emitSymbolAttribute(Sym, MCSA_Hidden);
496     OutStreamer->emitLabel(Sym);
497 
498     OutStreamer->emitInstruction(MCInstBuilder(AArch64::SBFMXri)
499                                      .addReg(AArch64::X16)
500                                      .addReg(Reg)
501                                      .addImm(4)
502                                      .addImm(55),
503                                  *STI);
504     OutStreamer->emitInstruction(
505         MCInstBuilder(AArch64::LDRBBroX)
506             .addReg(AArch64::W16)
507             .addReg(IsShort ? AArch64::X20 : AArch64::X9)
508             .addReg(AArch64::X16)
509             .addImm(0)
510             .addImm(0),
511         *STI);
512     OutStreamer->emitInstruction(
513         MCInstBuilder(AArch64::SUBSXrs)
514             .addReg(AArch64::XZR)
515             .addReg(AArch64::X16)
516             .addReg(Reg)
517             .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSR, 56)),
518         *STI);
519     MCSymbol *HandleMismatchOrPartialSym = OutContext.createTempSymbol();
520     OutStreamer->emitInstruction(
521         MCInstBuilder(AArch64::Bcc)
522             .addImm(AArch64CC::NE)
523             .addExpr(MCSymbolRefExpr::create(HandleMismatchOrPartialSym,
524                                              OutContext)),
525         *STI);
526     MCSymbol *ReturnSym = OutContext.createTempSymbol();
527     OutStreamer->emitLabel(ReturnSym);
528     OutStreamer->emitInstruction(
529         MCInstBuilder(AArch64::RET).addReg(AArch64::LR), *STI);
530     OutStreamer->emitLabel(HandleMismatchOrPartialSym);
531 
532     if (HasMatchAllTag) {
533       OutStreamer->emitInstruction(MCInstBuilder(AArch64::UBFMXri)
534                                        .addReg(AArch64::X16)
535                                        .addReg(Reg)
536                                        .addImm(56)
537                                        .addImm(63),
538                                    *STI);
539       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSXri)
540                                        .addReg(AArch64::XZR)
541                                        .addReg(AArch64::X16)
542                                        .addImm(MatchAllTag)
543                                        .addImm(0),
544                                    *STI);
545       OutStreamer->emitInstruction(
546           MCInstBuilder(AArch64::Bcc)
547               .addImm(AArch64CC::EQ)
548               .addExpr(MCSymbolRefExpr::create(ReturnSym, OutContext)),
549           *STI);
550     }
551 
552     if (IsShort) {
553       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSWri)
554                                        .addReg(AArch64::WZR)
555                                        .addReg(AArch64::W16)
556                                        .addImm(15)
557                                        .addImm(0),
558                                    *STI);
559       MCSymbol *HandleMismatchSym = OutContext.createTempSymbol();
560       OutStreamer->emitInstruction(
561           MCInstBuilder(AArch64::Bcc)
562               .addImm(AArch64CC::HI)
563               .addExpr(MCSymbolRefExpr::create(HandleMismatchSym, OutContext)),
564           *STI);
565 
566       OutStreamer->emitInstruction(
567           MCInstBuilder(AArch64::ANDXri)
568               .addReg(AArch64::X17)
569               .addReg(Reg)
570               .addImm(AArch64_AM::encodeLogicalImmediate(0xf, 64)),
571           *STI);
572       if (Size != 1)
573         OutStreamer->emitInstruction(MCInstBuilder(AArch64::ADDXri)
574                                          .addReg(AArch64::X17)
575                                          .addReg(AArch64::X17)
576                                          .addImm(Size - 1)
577                                          .addImm(0),
578                                      *STI);
579       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSWrs)
580                                        .addReg(AArch64::WZR)
581                                        .addReg(AArch64::W16)
582                                        .addReg(AArch64::W17)
583                                        .addImm(0),
584                                    *STI);
585       OutStreamer->emitInstruction(
586           MCInstBuilder(AArch64::Bcc)
587               .addImm(AArch64CC::LS)
588               .addExpr(MCSymbolRefExpr::create(HandleMismatchSym, OutContext)),
589           *STI);
590 
591       OutStreamer->emitInstruction(
592           MCInstBuilder(AArch64::ORRXri)
593               .addReg(AArch64::X16)
594               .addReg(Reg)
595               .addImm(AArch64_AM::encodeLogicalImmediate(0xf, 64)),
596           *STI);
597       OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDRBBui)
598                                        .addReg(AArch64::W16)
599                                        .addReg(AArch64::X16)
600                                        .addImm(0),
601                                    *STI);
602       OutStreamer->emitInstruction(
603           MCInstBuilder(AArch64::SUBSXrs)
604               .addReg(AArch64::XZR)
605               .addReg(AArch64::X16)
606               .addReg(Reg)
607               .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSR, 56)),
608           *STI);
609       OutStreamer->emitInstruction(
610           MCInstBuilder(AArch64::Bcc)
611               .addImm(AArch64CC::EQ)
612               .addExpr(MCSymbolRefExpr::create(ReturnSym, OutContext)),
613           *STI);
614 
615       OutStreamer->emitLabel(HandleMismatchSym);
616     }
617 
618     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXpre)
619                                      .addReg(AArch64::SP)
620                                      .addReg(AArch64::X0)
621                                      .addReg(AArch64::X1)
622                                      .addReg(AArch64::SP)
623                                      .addImm(-32),
624                                  *STI);
625     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXi)
626                                      .addReg(AArch64::FP)
627                                      .addReg(AArch64::LR)
628                                      .addReg(AArch64::SP)
629                                      .addImm(29),
630                                  *STI);
631 
632     if (Reg != AArch64::X0)
633       OutStreamer->emitInstruction(MCInstBuilder(AArch64::ORRXrs)
634                                        .addReg(AArch64::X0)
635                                        .addReg(AArch64::XZR)
636                                        .addReg(Reg)
637                                        .addImm(0),
638                                    *STI);
639     OutStreamer->emitInstruction(
640         MCInstBuilder(AArch64::MOVZXi)
641             .addReg(AArch64::X1)
642             .addImm(AccessInfo & HWASanAccessInfo::RuntimeMask)
643             .addImm(0),
644         *STI);
645 
646     if (CompileKernel) {
647       // The Linux kernel's dynamic loader doesn't support GOT relative
648       // relocations, but it doesn't support late binding either, so just call
649       // the function directly.
650       OutStreamer->emitInstruction(
651           MCInstBuilder(AArch64::B).addExpr(HwasanTagMismatchRef), *STI);
652     } else {
653       // Intentionally load the GOT entry and branch to it, rather than possibly
654       // late binding the function, which may clobber the registers before we
655       // have a chance to save them.
656       OutStreamer->emitInstruction(
657           MCInstBuilder(AArch64::ADRP)
658               .addReg(AArch64::X16)
659               .addExpr(AArch64MCExpr::create(
660                   HwasanTagMismatchRef, AArch64MCExpr::VariantKind::VK_GOT_PAGE,
661                   OutContext)),
662           *STI);
663       OutStreamer->emitInstruction(
664           MCInstBuilder(AArch64::LDRXui)
665               .addReg(AArch64::X16)
666               .addReg(AArch64::X16)
667               .addExpr(AArch64MCExpr::create(
668                   HwasanTagMismatchRef, AArch64MCExpr::VariantKind::VK_GOT_LO12,
669                   OutContext)),
670           *STI);
671       OutStreamer->emitInstruction(
672           MCInstBuilder(AArch64::BR).addReg(AArch64::X16), *STI);
673     }
674   }
675 }
676 
677 void AArch64AsmPrinter::emitEndOfAsmFile(Module &M) {
678   emitHwasanMemaccessSymbols(M);
679 
680   const Triple &TT = TM.getTargetTriple();
681   if (TT.isOSBinFormatMachO()) {
682     // Funny Darwin hack: This flag tells the linker that no global symbols
683     // contain code that falls through to other global symbols (e.g. the obvious
684     // implementation of multiple entry points).  If this doesn't occur, the
685     // linker can safely perform dead code stripping.  Since LLVM never
686     // generates code that does this, it is always safe to set.
687     OutStreamer->emitAssemblerFlag(MCAF_SubsectionsViaSymbols);
688   }
689 
690   // Emit stack and fault map information.
691   FM.serializeToFaultMapSection();
692 
693 }
694 
695 void AArch64AsmPrinter::emitLOHs() {
696   SmallVector<MCSymbol *, 3> MCArgs;
697 
698   for (const auto &D : AArch64FI->getLOHContainer()) {
699     for (const MachineInstr *MI : D.getArgs()) {
700       MInstToMCSymbol::iterator LabelIt = LOHInstToLabel.find(MI);
701       assert(LabelIt != LOHInstToLabel.end() &&
702              "Label hasn't been inserted for LOH related instruction");
703       MCArgs.push_back(LabelIt->second);
704     }
705     OutStreamer->emitLOHDirective(D.getKind(), MCArgs);
706     MCArgs.clear();
707   }
708 }
709 
710 void AArch64AsmPrinter::emitFunctionBodyEnd() {
711   if (!AArch64FI->getLOHRelated().empty())
712     emitLOHs();
713 }
714 
715 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
716 MCSymbol *AArch64AsmPrinter::GetCPISymbol(unsigned CPID) const {
717   // Darwin uses a linker-private symbol name for constant-pools (to
718   // avoid addends on the relocation?), ELF has no such concept and
719   // uses a normal private symbol.
720   if (!getDataLayout().getLinkerPrivateGlobalPrefix().empty())
721     return OutContext.getOrCreateSymbol(
722         Twine(getDataLayout().getLinkerPrivateGlobalPrefix()) + "CPI" +
723         Twine(getFunctionNumber()) + "_" + Twine(CPID));
724 
725   return AsmPrinter::GetCPISymbol(CPID);
726 }
727 
728 void AArch64AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNum,
729                                      raw_ostream &O) {
730   const MachineOperand &MO = MI->getOperand(OpNum);
731   switch (MO.getType()) {
732   default:
733     llvm_unreachable("<unknown operand type>");
734   case MachineOperand::MO_Register: {
735     Register Reg = MO.getReg();
736     assert(Reg.isPhysical());
737     assert(!MO.getSubReg() && "Subregs should be eliminated!");
738     O << AArch64InstPrinter::getRegisterName(Reg);
739     break;
740   }
741   case MachineOperand::MO_Immediate: {
742     O << MO.getImm();
743     break;
744   }
745   case MachineOperand::MO_GlobalAddress: {
746     PrintSymbolOperand(MO, O);
747     break;
748   }
749   case MachineOperand::MO_BlockAddress: {
750     MCSymbol *Sym = GetBlockAddressSymbol(MO.getBlockAddress());
751     Sym->print(O, MAI);
752     break;
753   }
754   }
755 }
756 
757 bool AArch64AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
758                                           raw_ostream &O) {
759   Register Reg = MO.getReg();
760   switch (Mode) {
761   default:
762     return true; // Unknown mode.
763   case 'w':
764     Reg = getWRegFromXReg(Reg);
765     break;
766   case 'x':
767     Reg = getXRegFromWReg(Reg);
768     break;
769   case 't':
770     Reg = getXRegFromXRegTuple(Reg);
771     break;
772   }
773 
774   O << AArch64InstPrinter::getRegisterName(Reg);
775   return false;
776 }
777 
778 // Prints the register in MO using class RC using the offset in the
779 // new register class. This should not be used for cross class
780 // printing.
781 bool AArch64AsmPrinter::printAsmRegInClass(const MachineOperand &MO,
782                                            const TargetRegisterClass *RC,
783                                            unsigned AltName, raw_ostream &O) {
784   assert(MO.isReg() && "Should only get here with a register!");
785   const TargetRegisterInfo *RI = STI->getRegisterInfo();
786   Register Reg = MO.getReg();
787   unsigned RegToPrint = RC->getRegister(RI->getEncodingValue(Reg));
788   if (!RI->regsOverlap(RegToPrint, Reg))
789     return true;
790   O << AArch64InstPrinter::getRegisterName(RegToPrint, AltName);
791   return false;
792 }
793 
794 bool AArch64AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
795                                         const char *ExtraCode, raw_ostream &O) {
796   const MachineOperand &MO = MI->getOperand(OpNum);
797 
798   // First try the generic code, which knows about modifiers like 'c' and 'n'.
799   if (!AsmPrinter::PrintAsmOperand(MI, OpNum, ExtraCode, O))
800     return false;
801 
802   // Does this asm operand have a single letter operand modifier?
803   if (ExtraCode && ExtraCode[0]) {
804     if (ExtraCode[1] != 0)
805       return true; // Unknown modifier.
806 
807     switch (ExtraCode[0]) {
808     default:
809       return true; // Unknown modifier.
810     case 'w':      // Print W register
811     case 'x':      // Print X register
812       if (MO.isReg())
813         return printAsmMRegister(MO, ExtraCode[0], O);
814       if (MO.isImm() && MO.getImm() == 0) {
815         unsigned Reg = ExtraCode[0] == 'w' ? AArch64::WZR : AArch64::XZR;
816         O << AArch64InstPrinter::getRegisterName(Reg);
817         return false;
818       }
819       printOperand(MI, OpNum, O);
820       return false;
821     case 'b': // Print B register.
822     case 'h': // Print H register.
823     case 's': // Print S register.
824     case 'd': // Print D register.
825     case 'q': // Print Q register.
826     case 'z': // Print Z register.
827       if (MO.isReg()) {
828         const TargetRegisterClass *RC;
829         switch (ExtraCode[0]) {
830         case 'b':
831           RC = &AArch64::FPR8RegClass;
832           break;
833         case 'h':
834           RC = &AArch64::FPR16RegClass;
835           break;
836         case 's':
837           RC = &AArch64::FPR32RegClass;
838           break;
839         case 'd':
840           RC = &AArch64::FPR64RegClass;
841           break;
842         case 'q':
843           RC = &AArch64::FPR128RegClass;
844           break;
845         case 'z':
846           RC = &AArch64::ZPRRegClass;
847           break;
848         default:
849           return true;
850         }
851         return printAsmRegInClass(MO, RC, AArch64::NoRegAltName, O);
852       }
853       printOperand(MI, OpNum, O);
854       return false;
855     }
856   }
857 
858   // According to ARM, we should emit x and v registers unless we have a
859   // modifier.
860   if (MO.isReg()) {
861     Register Reg = MO.getReg();
862 
863     // If this is a w or x register, print an x register.
864     if (AArch64::GPR32allRegClass.contains(Reg) ||
865         AArch64::GPR64allRegClass.contains(Reg))
866       return printAsmMRegister(MO, 'x', O);
867 
868     // If this is an x register tuple, print an x register.
869     if (AArch64::GPR64x8ClassRegClass.contains(Reg))
870       return printAsmMRegister(MO, 't', O);
871 
872     unsigned AltName = AArch64::NoRegAltName;
873     const TargetRegisterClass *RegClass;
874     if (AArch64::ZPRRegClass.contains(Reg)) {
875       RegClass = &AArch64::ZPRRegClass;
876     } else if (AArch64::PPRRegClass.contains(Reg)) {
877       RegClass = &AArch64::PPRRegClass;
878     } else {
879       RegClass = &AArch64::FPR128RegClass;
880       AltName = AArch64::vreg;
881     }
882 
883     // If this is a b, h, s, d, or q register, print it as a v register.
884     return printAsmRegInClass(MO, RegClass, AltName, O);
885   }
886 
887   printOperand(MI, OpNum, O);
888   return false;
889 }
890 
891 bool AArch64AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
892                                               unsigned OpNum,
893                                               const char *ExtraCode,
894                                               raw_ostream &O) {
895   if (ExtraCode && ExtraCode[0] && ExtraCode[0] != 'a')
896     return true; // Unknown modifier.
897 
898   const MachineOperand &MO = MI->getOperand(OpNum);
899   assert(MO.isReg() && "unexpected inline asm memory operand");
900   O << "[" << AArch64InstPrinter::getRegisterName(MO.getReg()) << "]";
901   return false;
902 }
903 
904 void AArch64AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
905                                                raw_ostream &OS) {
906   unsigned NOps = MI->getNumOperands();
907   assert(NOps == 4);
908   OS << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
909   // cast away const; DIetc do not take const operands for some reason.
910   OS << MI->getDebugVariable()->getName();
911   OS << " <- ";
912   // Frame address.  Currently handles register +- offset only.
913   assert(MI->isIndirectDebugValue());
914   OS << '[';
915   for (unsigned I = 0, E = std::distance(MI->debug_operands().begin(),
916                                          MI->debug_operands().end());
917        I < E; ++I) {
918     if (I != 0)
919       OS << ", ";
920     printOperand(MI, I, OS);
921   }
922   OS << ']';
923   OS << "+";
924   printOperand(MI, NOps - 2, OS);
925 }
926 
927 void AArch64AsmPrinter::emitJumpTableInfo() {
928   const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
929   if (!MJTI) return;
930 
931   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
932   if (JT.empty()) return;
933 
934   const TargetLoweringObjectFile &TLOF = getObjFileLowering();
935   MCSection *ReadOnlySec = TLOF.getSectionForJumpTable(MF->getFunction(), TM);
936   OutStreamer->switchSection(ReadOnlySec);
937 
938   auto AFI = MF->getInfo<AArch64FunctionInfo>();
939   for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
940     const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
941 
942     // If this jump table was deleted, ignore it.
943     if (JTBBs.empty()) continue;
944 
945     unsigned Size = AFI->getJumpTableEntrySize(JTI);
946     emitAlignment(Align(Size));
947     OutStreamer->emitLabel(GetJTISymbol(JTI));
948 
949     const MCSymbol *BaseSym = AArch64FI->getJumpTableEntryPCRelSymbol(JTI);
950     const MCExpr *Base = MCSymbolRefExpr::create(BaseSym, OutContext);
951 
952     for (auto *JTBB : JTBBs) {
953       const MCExpr *Value =
954           MCSymbolRefExpr::create(JTBB->getSymbol(), OutContext);
955 
956       // Each entry is:
957       //     .byte/.hword (LBB - Lbase)>>2
958       // or plain:
959       //     .word LBB - Lbase
960       Value = MCBinaryExpr::createSub(Value, Base, OutContext);
961       if (Size != 4)
962         Value = MCBinaryExpr::createLShr(
963             Value, MCConstantExpr::create(2, OutContext), OutContext);
964 
965       OutStreamer->emitValue(Value, Size);
966     }
967   }
968 }
969 
970 void AArch64AsmPrinter::emitFunctionEntryLabel() {
971   if (MF->getFunction().getCallingConv() == CallingConv::AArch64_VectorCall ||
972       MF->getFunction().getCallingConv() ==
973           CallingConv::AArch64_SVE_VectorCall ||
974       MF->getInfo<AArch64FunctionInfo>()->isSVECC()) {
975     auto *TS =
976         static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
977     TS->emitDirectiveVariantPCS(CurrentFnSym);
978   }
979 
980   return AsmPrinter::emitFunctionEntryLabel();
981 }
982 
983 /// Small jump tables contain an unsigned byte or half, representing the offset
984 /// from the lowest-addressed possible destination to the desired basic
985 /// block. Since all instructions are 4-byte aligned, this is further compressed
986 /// by counting in instructions rather than bytes (i.e. divided by 4). So, to
987 /// materialize the correct destination we need:
988 ///
989 ///             adr xDest, .LBB0_0
990 ///             ldrb wScratch, [xTable, xEntry]   (with "lsl #1" for ldrh).
991 ///             add xDest, xDest, xScratch (with "lsl #2" for smaller entries)
992 void AArch64AsmPrinter::LowerJumpTableDest(llvm::MCStreamer &OutStreamer,
993                                            const llvm::MachineInstr &MI) {
994   Register DestReg = MI.getOperand(0).getReg();
995   Register ScratchReg = MI.getOperand(1).getReg();
996   Register ScratchRegW =
997       STI->getRegisterInfo()->getSubReg(ScratchReg, AArch64::sub_32);
998   Register TableReg = MI.getOperand(2).getReg();
999   Register EntryReg = MI.getOperand(3).getReg();
1000   int JTIdx = MI.getOperand(4).getIndex();
1001   int Size = AArch64FI->getJumpTableEntrySize(JTIdx);
1002 
1003   // This has to be first because the compression pass based its reachability
1004   // calculations on the start of the JumpTableDest instruction.
1005   auto Label =
1006       MF->getInfo<AArch64FunctionInfo>()->getJumpTableEntryPCRelSymbol(JTIdx);
1007 
1008   // If we don't already have a symbol to use as the base, use the ADR
1009   // instruction itself.
1010   if (!Label) {
1011     Label = MF->getContext().createTempSymbol();
1012     AArch64FI->setJumpTableEntryInfo(JTIdx, Size, Label);
1013     OutStreamer.emitLabel(Label);
1014   }
1015 
1016   auto LabelExpr = MCSymbolRefExpr::create(Label, MF->getContext());
1017   EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::ADR)
1018                                   .addReg(DestReg)
1019                                   .addExpr(LabelExpr));
1020 
1021   // Load the number of instruction-steps to offset from the label.
1022   unsigned LdrOpcode;
1023   switch (Size) {
1024   case 1: LdrOpcode = AArch64::LDRBBroX; break;
1025   case 2: LdrOpcode = AArch64::LDRHHroX; break;
1026   case 4: LdrOpcode = AArch64::LDRSWroX; break;
1027   default:
1028     llvm_unreachable("Unknown jump table size");
1029   }
1030 
1031   EmitToStreamer(OutStreamer, MCInstBuilder(LdrOpcode)
1032                                   .addReg(Size == 4 ? ScratchReg : ScratchRegW)
1033                                   .addReg(TableReg)
1034                                   .addReg(EntryReg)
1035                                   .addImm(0)
1036                                   .addImm(Size == 1 ? 0 : 1));
1037 
1038   // Add to the already materialized base label address, multiplying by 4 if
1039   // compressed.
1040   EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::ADDXrs)
1041                                   .addReg(DestReg)
1042                                   .addReg(DestReg)
1043                                   .addReg(ScratchReg)
1044                                   .addImm(Size == 4 ? 0 : 2));
1045 }
1046 
1047 void AArch64AsmPrinter::LowerMOPS(llvm::MCStreamer &OutStreamer,
1048                                   const llvm::MachineInstr &MI) {
1049   unsigned Opcode = MI.getOpcode();
1050   assert(STI->hasMOPS());
1051   assert(STI->hasMTE() || Opcode != AArch64::MOPSMemorySetTaggingPseudo);
1052 
1053   const auto Ops = [Opcode]() -> std::array<unsigned, 3> {
1054     if (Opcode == AArch64::MOPSMemoryCopyPseudo)
1055       return {AArch64::CPYFP, AArch64::CPYFM, AArch64::CPYFE};
1056     if (Opcode == AArch64::MOPSMemoryMovePseudo)
1057       return {AArch64::CPYP, AArch64::CPYM, AArch64::CPYE};
1058     if (Opcode == AArch64::MOPSMemorySetPseudo)
1059       return {AArch64::SETP, AArch64::SETM, AArch64::SETE};
1060     if (Opcode == AArch64::MOPSMemorySetTaggingPseudo)
1061       return {AArch64::SETGP, AArch64::SETGM, AArch64::MOPSSETGE};
1062     llvm_unreachable("Unhandled memory operation pseudo");
1063   }();
1064   const bool IsSet = Opcode == AArch64::MOPSMemorySetPseudo ||
1065                      Opcode == AArch64::MOPSMemorySetTaggingPseudo;
1066 
1067   for (auto Op : Ops) {
1068     int i = 0;
1069     auto MCIB = MCInstBuilder(Op);
1070     // Destination registers
1071     MCIB.addReg(MI.getOperand(i++).getReg());
1072     MCIB.addReg(MI.getOperand(i++).getReg());
1073     if (!IsSet)
1074       MCIB.addReg(MI.getOperand(i++).getReg());
1075     // Input registers
1076     MCIB.addReg(MI.getOperand(i++).getReg());
1077     MCIB.addReg(MI.getOperand(i++).getReg());
1078     MCIB.addReg(MI.getOperand(i++).getReg());
1079 
1080     EmitToStreamer(OutStreamer, MCIB);
1081   }
1082 }
1083 
1084 void AArch64AsmPrinter::LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM,
1085                                       const MachineInstr &MI) {
1086   unsigned NumNOPBytes = StackMapOpers(&MI).getNumPatchBytes();
1087 
1088   auto &Ctx = OutStreamer.getContext();
1089   MCSymbol *MILabel = Ctx.createTempSymbol();
1090   OutStreamer.emitLabel(MILabel);
1091 
1092   SM.recordStackMap(*MILabel, MI);
1093   assert(NumNOPBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
1094 
1095   // Scan ahead to trim the shadow.
1096   const MachineBasicBlock &MBB = *MI.getParent();
1097   MachineBasicBlock::const_iterator MII(MI);
1098   ++MII;
1099   while (NumNOPBytes > 0) {
1100     if (MII == MBB.end() || MII->isCall() ||
1101         MII->getOpcode() == AArch64::DBG_VALUE ||
1102         MII->getOpcode() == TargetOpcode::PATCHPOINT ||
1103         MII->getOpcode() == TargetOpcode::STACKMAP)
1104       break;
1105     ++MII;
1106     NumNOPBytes -= 4;
1107   }
1108 
1109   // Emit nops.
1110   for (unsigned i = 0; i < NumNOPBytes; i += 4)
1111     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1112 }
1113 
1114 // Lower a patchpoint of the form:
1115 // [<def>], <id>, <numBytes>, <target>, <numArgs>
1116 void AArch64AsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM,
1117                                         const MachineInstr &MI) {
1118   auto &Ctx = OutStreamer.getContext();
1119   MCSymbol *MILabel = Ctx.createTempSymbol();
1120   OutStreamer.emitLabel(MILabel);
1121   SM.recordPatchPoint(*MILabel, MI);
1122 
1123   PatchPointOpers Opers(&MI);
1124 
1125   int64_t CallTarget = Opers.getCallTarget().getImm();
1126   unsigned EncodedBytes = 0;
1127   if (CallTarget) {
1128     assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget &&
1129            "High 16 bits of call target should be zero.");
1130     Register ScratchReg = MI.getOperand(Opers.getNextScratchIdx()).getReg();
1131     EncodedBytes = 16;
1132     // Materialize the jump address:
1133     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVZXi)
1134                                     .addReg(ScratchReg)
1135                                     .addImm((CallTarget >> 32) & 0xFFFF)
1136                                     .addImm(32));
1137     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKXi)
1138                                     .addReg(ScratchReg)
1139                                     .addReg(ScratchReg)
1140                                     .addImm((CallTarget >> 16) & 0xFFFF)
1141                                     .addImm(16));
1142     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKXi)
1143                                     .addReg(ScratchReg)
1144                                     .addReg(ScratchReg)
1145                                     .addImm(CallTarget & 0xFFFF)
1146                                     .addImm(0));
1147     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::BLR).addReg(ScratchReg));
1148   }
1149   // Emit padding.
1150   unsigned NumBytes = Opers.getNumPatchBytes();
1151   assert(NumBytes >= EncodedBytes &&
1152          "Patchpoint can't request size less than the length of a call.");
1153   assert((NumBytes - EncodedBytes) % 4 == 0 &&
1154          "Invalid number of NOP bytes requested!");
1155   for (unsigned i = EncodedBytes; i < NumBytes; i += 4)
1156     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1157 }
1158 
1159 void AArch64AsmPrinter::LowerSTATEPOINT(MCStreamer &OutStreamer, StackMaps &SM,
1160                                         const MachineInstr &MI) {
1161   StatepointOpers SOpers(&MI);
1162   if (unsigned PatchBytes = SOpers.getNumPatchBytes()) {
1163     assert(PatchBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
1164     for (unsigned i = 0; i < PatchBytes; i += 4)
1165       EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1166   } else {
1167     // Lower call target and choose correct opcode
1168     const MachineOperand &CallTarget = SOpers.getCallTarget();
1169     MCOperand CallTargetMCOp;
1170     unsigned CallOpcode;
1171     switch (CallTarget.getType()) {
1172     case MachineOperand::MO_GlobalAddress:
1173     case MachineOperand::MO_ExternalSymbol:
1174       MCInstLowering.lowerOperand(CallTarget, CallTargetMCOp);
1175       CallOpcode = AArch64::BL;
1176       break;
1177     case MachineOperand::MO_Immediate:
1178       CallTargetMCOp = MCOperand::createImm(CallTarget.getImm());
1179       CallOpcode = AArch64::BL;
1180       break;
1181     case MachineOperand::MO_Register:
1182       CallTargetMCOp = MCOperand::createReg(CallTarget.getReg());
1183       CallOpcode = AArch64::BLR;
1184       break;
1185     default:
1186       llvm_unreachable("Unsupported operand type in statepoint call target");
1187       break;
1188     }
1189 
1190     EmitToStreamer(OutStreamer,
1191                    MCInstBuilder(CallOpcode).addOperand(CallTargetMCOp));
1192   }
1193 
1194   auto &Ctx = OutStreamer.getContext();
1195   MCSymbol *MILabel = Ctx.createTempSymbol();
1196   OutStreamer.emitLabel(MILabel);
1197   SM.recordStatepoint(*MILabel, MI);
1198 }
1199 
1200 void AArch64AsmPrinter::LowerFAULTING_OP(const MachineInstr &FaultingMI) {
1201   // FAULTING_LOAD_OP <def>, <faltinf type>, <MBB handler>,
1202   //                  <opcode>, <operands>
1203 
1204   Register DefRegister = FaultingMI.getOperand(0).getReg();
1205   FaultMaps::FaultKind FK =
1206       static_cast<FaultMaps::FaultKind>(FaultingMI.getOperand(1).getImm());
1207   MCSymbol *HandlerLabel = FaultingMI.getOperand(2).getMBB()->getSymbol();
1208   unsigned Opcode = FaultingMI.getOperand(3).getImm();
1209   unsigned OperandsBeginIdx = 4;
1210 
1211   auto &Ctx = OutStreamer->getContext();
1212   MCSymbol *FaultingLabel = Ctx.createTempSymbol();
1213   OutStreamer->emitLabel(FaultingLabel);
1214 
1215   assert(FK < FaultMaps::FaultKindMax && "Invalid Faulting Kind!");
1216   FM.recordFaultingOp(FK, FaultingLabel, HandlerLabel);
1217 
1218   MCInst MI;
1219   MI.setOpcode(Opcode);
1220 
1221   if (DefRegister != (Register)0)
1222     MI.addOperand(MCOperand::createReg(DefRegister));
1223 
1224   for (const MachineOperand &MO :
1225        llvm::drop_begin(FaultingMI.operands(), OperandsBeginIdx)) {
1226     MCOperand Dest;
1227     lowerOperand(MO, Dest);
1228     MI.addOperand(Dest);
1229   }
1230 
1231   OutStreamer->AddComment("on-fault: " + HandlerLabel->getName());
1232   OutStreamer->emitInstruction(MI, getSubtargetInfo());
1233 }
1234 
1235 void AArch64AsmPrinter::emitFMov0(const MachineInstr &MI) {
1236   Register DestReg = MI.getOperand(0).getReg();
1237   if (STI->hasZeroCycleZeroingFP() && !STI->hasZeroCycleZeroingFPWorkaround() &&
1238       STI->hasNEON()) {
1239     // Convert H/S register to corresponding D register
1240     if (AArch64::H0 <= DestReg && DestReg <= AArch64::H31)
1241       DestReg = AArch64::D0 + (DestReg - AArch64::H0);
1242     else if (AArch64::S0 <= DestReg && DestReg <= AArch64::S31)
1243       DestReg = AArch64::D0 + (DestReg - AArch64::S0);
1244     else
1245       assert(AArch64::D0 <= DestReg && DestReg <= AArch64::D31);
1246 
1247     MCInst MOVI;
1248     MOVI.setOpcode(AArch64::MOVID);
1249     MOVI.addOperand(MCOperand::createReg(DestReg));
1250     MOVI.addOperand(MCOperand::createImm(0));
1251     EmitToStreamer(*OutStreamer, MOVI);
1252   } else {
1253     MCInst FMov;
1254     switch (MI.getOpcode()) {
1255     default: llvm_unreachable("Unexpected opcode");
1256     case AArch64::FMOVH0:
1257       FMov.setOpcode(AArch64::FMOVWHr);
1258       FMov.addOperand(MCOperand::createReg(DestReg));
1259       FMov.addOperand(MCOperand::createReg(AArch64::WZR));
1260       break;
1261     case AArch64::FMOVS0:
1262       FMov.setOpcode(AArch64::FMOVWSr);
1263       FMov.addOperand(MCOperand::createReg(DestReg));
1264       FMov.addOperand(MCOperand::createReg(AArch64::WZR));
1265       break;
1266     case AArch64::FMOVD0:
1267       FMov.setOpcode(AArch64::FMOVXDr);
1268       FMov.addOperand(MCOperand::createReg(DestReg));
1269       FMov.addOperand(MCOperand::createReg(AArch64::XZR));
1270       break;
1271     }
1272     EmitToStreamer(*OutStreamer, FMov);
1273   }
1274 }
1275 
1276 // Simple pseudo-instructions have their lowering (with expansion to real
1277 // instructions) auto-generated.
1278 #include "AArch64GenMCPseudoLowering.inc"
1279 
1280 void AArch64AsmPrinter::emitInstruction(const MachineInstr *MI) {
1281   AArch64_MC::verifyInstructionPredicates(MI->getOpcode(), STI->getFeatureBits());
1282 
1283   // Do any auto-generated pseudo lowerings.
1284   if (emitPseudoExpansionLowering(*OutStreamer, MI))
1285     return;
1286 
1287   if (MI->getOpcode() == AArch64::ADRP) {
1288     for (auto &Opd : MI->operands()) {
1289       if (Opd.isSymbol() && StringRef(Opd.getSymbolName()) ==
1290                                 "swift_async_extendedFramePointerFlags") {
1291         ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags = true;
1292       }
1293     }
1294   }
1295 
1296   if (AArch64FI->getLOHRelated().count(MI)) {
1297     // Generate a label for LOH related instruction
1298     MCSymbol *LOHLabel = createTempSymbol("loh");
1299     // Associate the instruction with the label
1300     LOHInstToLabel[MI] = LOHLabel;
1301     OutStreamer->emitLabel(LOHLabel);
1302   }
1303 
1304   AArch64TargetStreamer *TS =
1305     static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
1306   // Do any manual lowerings.
1307   switch (MI->getOpcode()) {
1308   default:
1309     break;
1310   case AArch64::HINT: {
1311     // CurrentPatchableFunctionEntrySym can be CurrentFnBegin only for
1312     // -fpatchable-function-entry=N,0. The entry MBB is guaranteed to be
1313     // non-empty. If MI is the initial BTI, place the
1314     // __patchable_function_entries label after BTI.
1315     if (CurrentPatchableFunctionEntrySym &&
1316         CurrentPatchableFunctionEntrySym == CurrentFnBegin &&
1317         MI == &MF->front().front()) {
1318       int64_t Imm = MI->getOperand(0).getImm();
1319       if ((Imm & 32) && (Imm & 6)) {
1320         MCInst Inst;
1321         MCInstLowering.Lower(MI, Inst);
1322         EmitToStreamer(*OutStreamer, Inst);
1323         CurrentPatchableFunctionEntrySym = createTempSymbol("patch");
1324         OutStreamer->emitLabel(CurrentPatchableFunctionEntrySym);
1325         return;
1326       }
1327     }
1328     break;
1329   }
1330     case AArch64::MOVMCSym: {
1331       Register DestReg = MI->getOperand(0).getReg();
1332       const MachineOperand &MO_Sym = MI->getOperand(1);
1333       MachineOperand Hi_MOSym(MO_Sym), Lo_MOSym(MO_Sym);
1334       MCOperand Hi_MCSym, Lo_MCSym;
1335 
1336       Hi_MOSym.setTargetFlags(AArch64II::MO_G1 | AArch64II::MO_S);
1337       Lo_MOSym.setTargetFlags(AArch64II::MO_G0 | AArch64II::MO_NC);
1338 
1339       MCInstLowering.lowerOperand(Hi_MOSym, Hi_MCSym);
1340       MCInstLowering.lowerOperand(Lo_MOSym, Lo_MCSym);
1341 
1342       MCInst MovZ;
1343       MovZ.setOpcode(AArch64::MOVZXi);
1344       MovZ.addOperand(MCOperand::createReg(DestReg));
1345       MovZ.addOperand(Hi_MCSym);
1346       MovZ.addOperand(MCOperand::createImm(16));
1347       EmitToStreamer(*OutStreamer, MovZ);
1348 
1349       MCInst MovK;
1350       MovK.setOpcode(AArch64::MOVKXi);
1351       MovK.addOperand(MCOperand::createReg(DestReg));
1352       MovK.addOperand(MCOperand::createReg(DestReg));
1353       MovK.addOperand(Lo_MCSym);
1354       MovK.addOperand(MCOperand::createImm(0));
1355       EmitToStreamer(*OutStreamer, MovK);
1356       return;
1357   }
1358   case AArch64::MOVIv2d_ns:
1359     // If the target has <rdar://problem/16473581>, lower this
1360     // instruction to movi.16b instead.
1361     if (STI->hasZeroCycleZeroingFPWorkaround() &&
1362         MI->getOperand(1).getImm() == 0) {
1363       MCInst TmpInst;
1364       TmpInst.setOpcode(AArch64::MOVIv16b_ns);
1365       TmpInst.addOperand(MCOperand::createReg(MI->getOperand(0).getReg()));
1366       TmpInst.addOperand(MCOperand::createImm(MI->getOperand(1).getImm()));
1367       EmitToStreamer(*OutStreamer, TmpInst);
1368       return;
1369     }
1370     break;
1371 
1372   case AArch64::DBG_VALUE:
1373   case AArch64::DBG_VALUE_LIST:
1374     if (isVerbose() && OutStreamer->hasRawTextSupport()) {
1375       SmallString<128> TmpStr;
1376       raw_svector_ostream OS(TmpStr);
1377       PrintDebugValueComment(MI, OS);
1378       OutStreamer->emitRawText(StringRef(OS.str()));
1379     }
1380     return;
1381 
1382   case AArch64::EMITBKEY: {
1383       ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
1384       if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1385           ExceptionHandlingType != ExceptionHandling::ARM)
1386         return;
1387 
1388       if (getFunctionCFISectionType(*MF) == CFISection::None)
1389         return;
1390 
1391       OutStreamer->emitCFIBKeyFrame();
1392       return;
1393   }
1394 
1395   case AArch64::EMITMTETAGGED: {
1396     ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
1397     if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1398         ExceptionHandlingType != ExceptionHandling::ARM)
1399       return;
1400 
1401     if (getFunctionCFISectionType(*MF) != CFISection::None)
1402       OutStreamer->emitCFIMTETaggedFrame();
1403     return;
1404   }
1405 
1406   // Tail calls use pseudo instructions so they have the proper code-gen
1407   // attributes (isCall, isReturn, etc.). We lower them to the real
1408   // instruction here.
1409   case AArch64::TCRETURNri:
1410   case AArch64::TCRETURNriBTI:
1411   case AArch64::TCRETURNriALL: {
1412     MCInst TmpInst;
1413     TmpInst.setOpcode(AArch64::BR);
1414     TmpInst.addOperand(MCOperand::createReg(MI->getOperand(0).getReg()));
1415     EmitToStreamer(*OutStreamer, TmpInst);
1416     return;
1417   }
1418   case AArch64::TCRETURNdi: {
1419     MCOperand Dest;
1420     MCInstLowering.lowerOperand(MI->getOperand(0), Dest);
1421     MCInst TmpInst;
1422     TmpInst.setOpcode(AArch64::B);
1423     TmpInst.addOperand(Dest);
1424     EmitToStreamer(*OutStreamer, TmpInst);
1425     return;
1426   }
1427   case AArch64::SpeculationBarrierISBDSBEndBB: {
1428     // Print DSB SYS + ISB
1429     MCInst TmpInstDSB;
1430     TmpInstDSB.setOpcode(AArch64::DSB);
1431     TmpInstDSB.addOperand(MCOperand::createImm(0xf));
1432     EmitToStreamer(*OutStreamer, TmpInstDSB);
1433     MCInst TmpInstISB;
1434     TmpInstISB.setOpcode(AArch64::ISB);
1435     TmpInstISB.addOperand(MCOperand::createImm(0xf));
1436     EmitToStreamer(*OutStreamer, TmpInstISB);
1437     return;
1438   }
1439   case AArch64::SpeculationBarrierSBEndBB: {
1440     // Print SB
1441     MCInst TmpInstSB;
1442     TmpInstSB.setOpcode(AArch64::SB);
1443     EmitToStreamer(*OutStreamer, TmpInstSB);
1444     return;
1445   }
1446   case AArch64::TLSDESC_CALLSEQ: {
1447     /// lower this to:
1448     ///    adrp  x0, :tlsdesc:var
1449     ///    ldr   x1, [x0, #:tlsdesc_lo12:var]
1450     ///    add   x0, x0, #:tlsdesc_lo12:var
1451     ///    .tlsdesccall var
1452     ///    blr   x1
1453     ///    (TPIDR_EL0 offset now in x0)
1454     const MachineOperand &MO_Sym = MI->getOperand(0);
1455     MachineOperand MO_TLSDESC_LO12(MO_Sym), MO_TLSDESC(MO_Sym);
1456     MCOperand Sym, SymTLSDescLo12, SymTLSDesc;
1457     MO_TLSDESC_LO12.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGEOFF);
1458     MO_TLSDESC.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGE);
1459     MCInstLowering.lowerOperand(MO_Sym, Sym);
1460     MCInstLowering.lowerOperand(MO_TLSDESC_LO12, SymTLSDescLo12);
1461     MCInstLowering.lowerOperand(MO_TLSDESC, SymTLSDesc);
1462 
1463     MCInst Adrp;
1464     Adrp.setOpcode(AArch64::ADRP);
1465     Adrp.addOperand(MCOperand::createReg(AArch64::X0));
1466     Adrp.addOperand(SymTLSDesc);
1467     EmitToStreamer(*OutStreamer, Adrp);
1468 
1469     MCInst Ldr;
1470     if (STI->isTargetILP32()) {
1471       Ldr.setOpcode(AArch64::LDRWui);
1472       Ldr.addOperand(MCOperand::createReg(AArch64::W1));
1473     } else {
1474       Ldr.setOpcode(AArch64::LDRXui);
1475       Ldr.addOperand(MCOperand::createReg(AArch64::X1));
1476     }
1477     Ldr.addOperand(MCOperand::createReg(AArch64::X0));
1478     Ldr.addOperand(SymTLSDescLo12);
1479     Ldr.addOperand(MCOperand::createImm(0));
1480     EmitToStreamer(*OutStreamer, Ldr);
1481 
1482     MCInst Add;
1483     if (STI->isTargetILP32()) {
1484       Add.setOpcode(AArch64::ADDWri);
1485       Add.addOperand(MCOperand::createReg(AArch64::W0));
1486       Add.addOperand(MCOperand::createReg(AArch64::W0));
1487     } else {
1488       Add.setOpcode(AArch64::ADDXri);
1489       Add.addOperand(MCOperand::createReg(AArch64::X0));
1490       Add.addOperand(MCOperand::createReg(AArch64::X0));
1491     }
1492     Add.addOperand(SymTLSDescLo12);
1493     Add.addOperand(MCOperand::createImm(AArch64_AM::getShiftValue(0)));
1494     EmitToStreamer(*OutStreamer, Add);
1495 
1496     // Emit a relocation-annotation. This expands to no code, but requests
1497     // the following instruction gets an R_AARCH64_TLSDESC_CALL.
1498     MCInst TLSDescCall;
1499     TLSDescCall.setOpcode(AArch64::TLSDESCCALL);
1500     TLSDescCall.addOperand(Sym);
1501     EmitToStreamer(*OutStreamer, TLSDescCall);
1502 
1503     MCInst Blr;
1504     Blr.setOpcode(AArch64::BLR);
1505     Blr.addOperand(MCOperand::createReg(AArch64::X1));
1506     EmitToStreamer(*OutStreamer, Blr);
1507 
1508     return;
1509   }
1510 
1511   case AArch64::JumpTableDest32:
1512   case AArch64::JumpTableDest16:
1513   case AArch64::JumpTableDest8:
1514     LowerJumpTableDest(*OutStreamer, *MI);
1515     return;
1516 
1517   case AArch64::FMOVH0:
1518   case AArch64::FMOVS0:
1519   case AArch64::FMOVD0:
1520     emitFMov0(*MI);
1521     return;
1522 
1523   case AArch64::MOPSMemoryCopyPseudo:
1524   case AArch64::MOPSMemoryMovePseudo:
1525   case AArch64::MOPSMemorySetPseudo:
1526   case AArch64::MOPSMemorySetTaggingPseudo:
1527     LowerMOPS(*OutStreamer, *MI);
1528     return;
1529 
1530   case TargetOpcode::STACKMAP:
1531     return LowerSTACKMAP(*OutStreamer, SM, *MI);
1532 
1533   case TargetOpcode::PATCHPOINT:
1534     return LowerPATCHPOINT(*OutStreamer, SM, *MI);
1535 
1536   case TargetOpcode::STATEPOINT:
1537     return LowerSTATEPOINT(*OutStreamer, SM, *MI);
1538 
1539   case TargetOpcode::FAULTING_OP:
1540     return LowerFAULTING_OP(*MI);
1541 
1542   case TargetOpcode::PATCHABLE_FUNCTION_ENTER:
1543     LowerPATCHABLE_FUNCTION_ENTER(*MI);
1544     return;
1545 
1546   case TargetOpcode::PATCHABLE_FUNCTION_EXIT:
1547     LowerPATCHABLE_FUNCTION_EXIT(*MI);
1548     return;
1549 
1550   case TargetOpcode::PATCHABLE_TAIL_CALL:
1551     LowerPATCHABLE_TAIL_CALL(*MI);
1552     return;
1553 
1554   case AArch64::KCFI_CHECK:
1555     LowerKCFI_CHECK(*MI);
1556     return;
1557 
1558   case AArch64::HWASAN_CHECK_MEMACCESS:
1559   case AArch64::HWASAN_CHECK_MEMACCESS_SHORTGRANULES:
1560     LowerHWASAN_CHECK_MEMACCESS(*MI);
1561     return;
1562 
1563   case AArch64::SEH_StackAlloc:
1564     TS->emitARM64WinCFIAllocStack(MI->getOperand(0).getImm());
1565     return;
1566 
1567   case AArch64::SEH_SaveFPLR:
1568     TS->emitARM64WinCFISaveFPLR(MI->getOperand(0).getImm());
1569     return;
1570 
1571   case AArch64::SEH_SaveFPLR_X:
1572     assert(MI->getOperand(0).getImm() < 0 &&
1573            "Pre increment SEH opcode must have a negative offset");
1574     TS->emitARM64WinCFISaveFPLRX(-MI->getOperand(0).getImm());
1575     return;
1576 
1577   case AArch64::SEH_SaveReg:
1578     TS->emitARM64WinCFISaveReg(MI->getOperand(0).getImm(),
1579                                MI->getOperand(1).getImm());
1580     return;
1581 
1582   case AArch64::SEH_SaveReg_X:
1583     assert(MI->getOperand(1).getImm() < 0 &&
1584            "Pre increment SEH opcode must have a negative offset");
1585     TS->emitARM64WinCFISaveRegX(MI->getOperand(0).getImm(),
1586                                 -MI->getOperand(1).getImm());
1587     return;
1588 
1589   case AArch64::SEH_SaveRegP:
1590     if (MI->getOperand(1).getImm() == 30 && MI->getOperand(0).getImm() >= 19 &&
1591         MI->getOperand(0).getImm() <= 28) {
1592       assert((MI->getOperand(0).getImm() - 19) % 2 == 0 &&
1593              "Register paired with LR must be odd");
1594       TS->emitARM64WinCFISaveLRPair(MI->getOperand(0).getImm(),
1595                                     MI->getOperand(2).getImm());
1596       return;
1597     }
1598     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1599             "Non-consecutive registers not allowed for save_regp");
1600     TS->emitARM64WinCFISaveRegP(MI->getOperand(0).getImm(),
1601                                 MI->getOperand(2).getImm());
1602     return;
1603 
1604   case AArch64::SEH_SaveRegP_X:
1605     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1606             "Non-consecutive registers not allowed for save_regp_x");
1607     assert(MI->getOperand(2).getImm() < 0 &&
1608            "Pre increment SEH opcode must have a negative offset");
1609     TS->emitARM64WinCFISaveRegPX(MI->getOperand(0).getImm(),
1610                                  -MI->getOperand(2).getImm());
1611     return;
1612 
1613   case AArch64::SEH_SaveFReg:
1614     TS->emitARM64WinCFISaveFReg(MI->getOperand(0).getImm(),
1615                                 MI->getOperand(1).getImm());
1616     return;
1617 
1618   case AArch64::SEH_SaveFReg_X:
1619     assert(MI->getOperand(1).getImm() < 0 &&
1620            "Pre increment SEH opcode must have a negative offset");
1621     TS->emitARM64WinCFISaveFRegX(MI->getOperand(0).getImm(),
1622                                  -MI->getOperand(1).getImm());
1623     return;
1624 
1625   case AArch64::SEH_SaveFRegP:
1626     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1627             "Non-consecutive registers not allowed for save_regp");
1628     TS->emitARM64WinCFISaveFRegP(MI->getOperand(0).getImm(),
1629                                  MI->getOperand(2).getImm());
1630     return;
1631 
1632   case AArch64::SEH_SaveFRegP_X:
1633     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1634             "Non-consecutive registers not allowed for save_regp_x");
1635     assert(MI->getOperand(2).getImm() < 0 &&
1636            "Pre increment SEH opcode must have a negative offset");
1637     TS->emitARM64WinCFISaveFRegPX(MI->getOperand(0).getImm(),
1638                                   -MI->getOperand(2).getImm());
1639     return;
1640 
1641   case AArch64::SEH_SetFP:
1642     TS->emitARM64WinCFISetFP();
1643     return;
1644 
1645   case AArch64::SEH_AddFP:
1646     TS->emitARM64WinCFIAddFP(MI->getOperand(0).getImm());
1647     return;
1648 
1649   case AArch64::SEH_Nop:
1650     TS->emitARM64WinCFINop();
1651     return;
1652 
1653   case AArch64::SEH_PrologEnd:
1654     TS->emitARM64WinCFIPrologEnd();
1655     return;
1656 
1657   case AArch64::SEH_EpilogStart:
1658     TS->emitARM64WinCFIEpilogStart();
1659     return;
1660 
1661   case AArch64::SEH_EpilogEnd:
1662     TS->emitARM64WinCFIEpilogEnd();
1663     return;
1664 
1665   case AArch64::SEH_PACSignLR:
1666     TS->emitARM64WinCFIPACSignLR();
1667     return;
1668   }
1669 
1670   // Finally, do the automated lowerings for everything else.
1671   MCInst TmpInst;
1672   MCInstLowering.Lower(MI, TmpInst);
1673   EmitToStreamer(*OutStreamer, TmpInst);
1674 }
1675 
1676 // Force static initialization.
1677 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64AsmPrinter() {
1678   RegisterAsmPrinter<AArch64AsmPrinter> X(getTheAArch64leTarget());
1679   RegisterAsmPrinter<AArch64AsmPrinter> Y(getTheAArch64beTarget());
1680   RegisterAsmPrinter<AArch64AsmPrinter> Z(getTheARM64Target());
1681   RegisterAsmPrinter<AArch64AsmPrinter> W(getTheARM64_32Target());
1682   RegisterAsmPrinter<AArch64AsmPrinter> V(getTheAArch64_32Target());
1683 }
1684