xref: /freebsd/contrib/llvm-project/llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
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/Twine.h"
31 #include "llvm/BinaryFormat/COFF.h"
32 #include "llvm/BinaryFormat/ELF.h"
33 #include "llvm/BinaryFormat/MachO.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/MCSectionMachO.h"
52 #include "llvm/MC/MCStreamer.h"
53 #include "llvm/MC/MCSymbol.h"
54 #include "llvm/MC/TargetRegistry.h"
55 #include "llvm/Support/Casting.h"
56 #include "llvm/Support/CommandLine.h"
57 #include "llvm/Support/ErrorHandling.h"
58 #include "llvm/Support/raw_ostream.h"
59 #include "llvm/Target/TargetMachine.h"
60 #include "llvm/TargetParser/Triple.h"
61 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
62 #include <algorithm>
63 #include <cassert>
64 #include <cstdint>
65 #include <map>
66 #include <memory>
67 
68 using namespace llvm;
69 
70 #define DEBUG_TYPE "asm-printer"
71 
72 namespace {
73 
74 class AArch64AsmPrinter : public AsmPrinter {
75   AArch64MCInstLower MCInstLowering;
76   FaultMaps FM;
77   const AArch64Subtarget *STI;
78   bool ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags = false;
79 
80 public:
81   AArch64AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer)
82       : AsmPrinter(TM, std::move(Streamer)), MCInstLowering(OutContext, *this),
83         FM(*this) {}
84 
85   StringRef getPassName() const override { return "AArch64 Assembly Printer"; }
86 
87   /// Wrapper for MCInstLowering.lowerOperand() for the
88   /// tblgen'erated pseudo lowering.
89   bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp) const {
90     return MCInstLowering.lowerOperand(MO, MCOp);
91   }
92 
93   void emitStartOfAsmFile(Module &M) override;
94   void emitJumpTableInfo() override;
95   std::tuple<const MCSymbol *, uint64_t, const MCSymbol *,
96              codeview::JumpTableEntrySize>
97   getCodeViewJumpTableInfo(int JTI, const MachineInstr *BranchInstr,
98                            const MCSymbol *BranchLabel) const override;
99 
100   void emitFunctionEntryLabel() override;
101 
102   void LowerJumpTableDest(MCStreamer &OutStreamer, const MachineInstr &MI);
103 
104   void LowerMOPS(MCStreamer &OutStreamer, const MachineInstr &MI);
105 
106   void LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM,
107                      const MachineInstr &MI);
108   void LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM,
109                        const MachineInstr &MI);
110   void LowerSTATEPOINT(MCStreamer &OutStreamer, StackMaps &SM,
111                        const MachineInstr &MI);
112   void LowerFAULTING_OP(const MachineInstr &MI);
113 
114   void LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI);
115   void LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI);
116   void LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI);
117   void LowerPATCHABLE_EVENT_CALL(const MachineInstr &MI, bool Typed);
118 
119   typedef std::tuple<unsigned, bool, uint32_t> HwasanMemaccessTuple;
120   std::map<HwasanMemaccessTuple, MCSymbol *> HwasanMemaccessSymbols;
121   void LowerKCFI_CHECK(const MachineInstr &MI);
122   void LowerHWASAN_CHECK_MEMACCESS(const MachineInstr &MI);
123   void emitHwasanMemaccessSymbols(Module &M);
124 
125   void emitSled(const MachineInstr &MI, SledKind Kind);
126 
127   /// tblgen'erated driver function for lowering simple MI->MC
128   /// pseudo instructions.
129   bool emitPseudoExpansionLowering(MCStreamer &OutStreamer,
130                                    const MachineInstr *MI);
131 
132   void emitInstruction(const MachineInstr *MI) override;
133 
134   void emitFunctionHeaderComment() override;
135 
136   void getAnalysisUsage(AnalysisUsage &AU) const override {
137     AsmPrinter::getAnalysisUsage(AU);
138     AU.setPreservesAll();
139   }
140 
141   bool runOnMachineFunction(MachineFunction &MF) override {
142     AArch64FI = MF.getInfo<AArch64FunctionInfo>();
143     STI = &MF.getSubtarget<AArch64Subtarget>();
144 
145     SetupMachineFunction(MF);
146 
147     if (STI->isTargetCOFF()) {
148       bool Local = MF.getFunction().hasLocalLinkage();
149       COFF::SymbolStorageClass Scl =
150           Local ? COFF::IMAGE_SYM_CLASS_STATIC : COFF::IMAGE_SYM_CLASS_EXTERNAL;
151       int Type =
152         COFF::IMAGE_SYM_DTYPE_FUNCTION << COFF::SCT_COMPLEX_TYPE_SHIFT;
153 
154       OutStreamer->beginCOFFSymbolDef(CurrentFnSym);
155       OutStreamer->emitCOFFSymbolStorageClass(Scl);
156       OutStreamer->emitCOFFSymbolType(Type);
157       OutStreamer->endCOFFSymbolDef();
158     }
159 
160     // Emit the rest of the function body.
161     emitFunctionBody();
162 
163     // Emit the XRay table for this function.
164     emitXRayTable();
165 
166     // We didn't modify anything.
167     return false;
168   }
169 
170 private:
171   void printOperand(const MachineInstr *MI, unsigned OpNum, raw_ostream &O);
172   bool printAsmMRegister(const MachineOperand &MO, char Mode, raw_ostream &O);
173   bool printAsmRegInClass(const MachineOperand &MO,
174                           const TargetRegisterClass *RC, unsigned AltName,
175                           raw_ostream &O);
176 
177   bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
178                        const char *ExtraCode, raw_ostream &O) override;
179   bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
180                              const char *ExtraCode, raw_ostream &O) override;
181 
182   void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
183 
184   void emitFunctionBodyEnd() override;
185 
186   MCSymbol *GetCPISymbol(unsigned CPID) const override;
187   void emitEndOfAsmFile(Module &M) override;
188 
189   AArch64FunctionInfo *AArch64FI = nullptr;
190 
191   /// Emit the LOHs contained in AArch64FI.
192   void emitLOHs();
193 
194   /// Emit instruction to set float register to zero.
195   void emitFMov0(const MachineInstr &MI);
196 
197   using MInstToMCSymbol = std::map<const MachineInstr *, MCSymbol *>;
198 
199   MInstToMCSymbol LOHInstToLabel;
200 
201   bool shouldEmitWeakSwiftAsyncExtendedFramePointerFlags() const override {
202     return ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags;
203   }
204 
205   const MCSubtargetInfo *getIFuncMCSubtargetInfo() const override {
206     assert(STI);
207     return STI;
208   }
209   void emitMachOIFuncStubBody(Module &M, const GlobalIFunc &GI,
210                               MCSymbol *LazyPointer) override;
211   void emitMachOIFuncStubHelperBody(Module &M, const GlobalIFunc &GI,
212                                     MCSymbol *LazyPointer) override;
213 };
214 
215 } // end anonymous namespace
216 
217 void AArch64AsmPrinter::emitStartOfAsmFile(Module &M) {
218   const Triple &TT = TM.getTargetTriple();
219 
220   if (TT.isOSBinFormatCOFF()) {
221     // Emit an absolute @feat.00 symbol
222     MCSymbol *S = MMI->getContext().getOrCreateSymbol(StringRef("@feat.00"));
223     OutStreamer->beginCOFFSymbolDef(S);
224     OutStreamer->emitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_STATIC);
225     OutStreamer->emitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_NULL);
226     OutStreamer->endCOFFSymbolDef();
227     int64_t Feat00Value = 0;
228 
229     if (M.getModuleFlag("cfguard")) {
230       // Object is CFG-aware.
231       Feat00Value |= COFF::Feat00Flags::GuardCF;
232     }
233 
234     if (M.getModuleFlag("ehcontguard")) {
235       // Object also has EHCont.
236       Feat00Value |= COFF::Feat00Flags::GuardEHCont;
237     }
238 
239     if (M.getModuleFlag("ms-kernel")) {
240       // Object is compiled with /kernel.
241       Feat00Value |= COFF::Feat00Flags::Kernel;
242     }
243 
244     OutStreamer->emitSymbolAttribute(S, MCSA_Global);
245     OutStreamer->emitAssignment(
246         S, MCConstantExpr::create(Feat00Value, MMI->getContext()));
247   }
248 
249   if (!TT.isOSBinFormatELF())
250     return;
251 
252   // Assemble feature flags that may require creation of a note section.
253   unsigned Flags = 0;
254   if (const auto *BTE = mdconst::extract_or_null<ConstantInt>(
255           M.getModuleFlag("branch-target-enforcement")))
256     if (BTE->getZExtValue())
257       Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
258 
259   if (const auto *Sign = mdconst::extract_or_null<ConstantInt>(
260           M.getModuleFlag("sign-return-address")))
261     if (Sign->getZExtValue())
262       Flags |= ELF::GNU_PROPERTY_AARCH64_FEATURE_1_PAC;
263 
264   if (Flags == 0)
265     return;
266 
267   // Emit a .note.gnu.property section with the flags.
268   auto *TS =
269       static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
270   TS->emitNoteSection(Flags);
271 }
272 
273 void AArch64AsmPrinter::emitFunctionHeaderComment() {
274   const AArch64FunctionInfo *FI = MF->getInfo<AArch64FunctionInfo>();
275   std::optional<std::string> OutlinerString = FI->getOutliningStyle();
276   if (OutlinerString != std::nullopt)
277     OutStreamer->getCommentOS() << ' ' << OutlinerString;
278 }
279 
280 void AArch64AsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI)
281 {
282   const Function &F = MF->getFunction();
283   if (F.hasFnAttribute("patchable-function-entry")) {
284     unsigned Num;
285     if (F.getFnAttribute("patchable-function-entry")
286             .getValueAsString()
287             .getAsInteger(10, Num))
288       return;
289     emitNops(Num);
290     return;
291   }
292 
293   emitSled(MI, SledKind::FUNCTION_ENTER);
294 }
295 
296 void AArch64AsmPrinter::LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI) {
297   emitSled(MI, SledKind::FUNCTION_EXIT);
298 }
299 
300 void AArch64AsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI) {
301   emitSled(MI, SledKind::TAIL_CALL);
302 }
303 
304 void AArch64AsmPrinter::emitSled(const MachineInstr &MI, SledKind Kind) {
305   static const int8_t NoopsInSledCount = 7;
306   // We want to emit the following pattern:
307   //
308   // .Lxray_sled_N:
309   //   ALIGN
310   //   B #32
311   //   ; 7 NOP instructions (28 bytes)
312   // .tmpN
313   //
314   // We need the 28 bytes (7 instructions) because at runtime, we'd be patching
315   // over the full 32 bytes (8 instructions) with the following pattern:
316   //
317   //   STP X0, X30, [SP, #-16]! ; push X0 and the link register to the stack
318   //   LDR W17, #12 ; W17 := function ID
319   //   LDR X16,#12 ; X16 := addr of __xray_FunctionEntry or __xray_FunctionExit
320   //   BLR X16 ; call the tracing trampoline
321   //   ;DATA: 32 bits of function ID
322   //   ;DATA: lower 32 bits of the address of the trampoline
323   //   ;DATA: higher 32 bits of the address of the trampoline
324   //   LDP X0, X30, [SP], #16 ; pop X0 and the link register from the stack
325   //
326   OutStreamer->emitCodeAlignment(Align(4), &getSubtargetInfo());
327   auto CurSled = OutContext.createTempSymbol("xray_sled_", true);
328   OutStreamer->emitLabel(CurSled);
329   auto Target = OutContext.createTempSymbol();
330 
331   // Emit "B #32" instruction, which jumps over the next 28 bytes.
332   // The operand has to be the number of 4-byte instructions to jump over,
333   // including the current instruction.
334   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::B).addImm(8));
335 
336   for (int8_t I = 0; I < NoopsInSledCount; I++)
337     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
338 
339   OutStreamer->emitLabel(Target);
340   recordSled(CurSled, MI, Kind, 2);
341 }
342 
343 // Emit the following code for Intrinsic::{xray_customevent,xray_typedevent}
344 // (built-in functions __xray_customevent/__xray_typedevent).
345 //
346 // .Lxray_event_sled_N:
347 //   b 1f
348 //   save x0 and x1 (and also x2 for TYPED_EVENT_CALL)
349 //   set up x0 and x1 (and also x2 for TYPED_EVENT_CALL)
350 //   bl __xray_CustomEvent or __xray_TypedEvent
351 //   restore x0 and x1 (and also x2 for TYPED_EVENT_CALL)
352 // 1:
353 //
354 // There are 6 instructions for EVENT_CALL and 9 for TYPED_EVENT_CALL.
355 //
356 // Then record a sled of kind CUSTOM_EVENT or TYPED_EVENT.
357 // After patching, b .+N will become a nop.
358 void AArch64AsmPrinter::LowerPATCHABLE_EVENT_CALL(const MachineInstr &MI,
359                                                   bool Typed) {
360   auto &O = *OutStreamer;
361   MCSymbol *CurSled = OutContext.createTempSymbol("xray_sled_", true);
362   O.emitLabel(CurSled);
363   MCInst MovX0Op0 = MCInstBuilder(AArch64::ORRXrs)
364                         .addReg(AArch64::X0)
365                         .addReg(AArch64::XZR)
366                         .addReg(MI.getOperand(0).getReg())
367                         .addImm(0);
368   MCInst MovX1Op1 = MCInstBuilder(AArch64::ORRXrs)
369                         .addReg(AArch64::X1)
370                         .addReg(AArch64::XZR)
371                         .addReg(MI.getOperand(1).getReg())
372                         .addImm(0);
373   bool MachO = TM.getTargetTriple().isOSBinFormatMachO();
374   auto *Sym = MCSymbolRefExpr::create(
375       OutContext.getOrCreateSymbol(
376           Twine(MachO ? "_" : "") +
377           (Typed ? "__xray_TypedEvent" : "__xray_CustomEvent")),
378       OutContext);
379   if (Typed) {
380     O.AddComment("Begin XRay typed event");
381     EmitToStreamer(O, MCInstBuilder(AArch64::B).addImm(9));
382     EmitToStreamer(O, MCInstBuilder(AArch64::STPXpre)
383                           .addReg(AArch64::SP)
384                           .addReg(AArch64::X0)
385                           .addReg(AArch64::X1)
386                           .addReg(AArch64::SP)
387                           .addImm(-4));
388     EmitToStreamer(O, MCInstBuilder(AArch64::STRXui)
389                           .addReg(AArch64::X2)
390                           .addReg(AArch64::SP)
391                           .addImm(2));
392     EmitToStreamer(O, MovX0Op0);
393     EmitToStreamer(O, MovX1Op1);
394     EmitToStreamer(O, MCInstBuilder(AArch64::ORRXrs)
395                           .addReg(AArch64::X2)
396                           .addReg(AArch64::XZR)
397                           .addReg(MI.getOperand(2).getReg())
398                           .addImm(0));
399     EmitToStreamer(O, MCInstBuilder(AArch64::BL).addExpr(Sym));
400     EmitToStreamer(O, MCInstBuilder(AArch64::LDRXui)
401                           .addReg(AArch64::X2)
402                           .addReg(AArch64::SP)
403                           .addImm(2));
404     O.AddComment("End XRay typed event");
405     EmitToStreamer(O, MCInstBuilder(AArch64::LDPXpost)
406                           .addReg(AArch64::SP)
407                           .addReg(AArch64::X0)
408                           .addReg(AArch64::X1)
409                           .addReg(AArch64::SP)
410                           .addImm(4));
411 
412     recordSled(CurSled, MI, SledKind::TYPED_EVENT, 2);
413   } else {
414     O.AddComment("Begin XRay custom event");
415     EmitToStreamer(O, MCInstBuilder(AArch64::B).addImm(6));
416     EmitToStreamer(O, MCInstBuilder(AArch64::STPXpre)
417                           .addReg(AArch64::SP)
418                           .addReg(AArch64::X0)
419                           .addReg(AArch64::X1)
420                           .addReg(AArch64::SP)
421                           .addImm(-2));
422     EmitToStreamer(O, MovX0Op0);
423     EmitToStreamer(O, MovX1Op1);
424     EmitToStreamer(O, MCInstBuilder(AArch64::BL).addExpr(Sym));
425     O.AddComment("End XRay custom event");
426     EmitToStreamer(O, MCInstBuilder(AArch64::LDPXpost)
427                           .addReg(AArch64::SP)
428                           .addReg(AArch64::X0)
429                           .addReg(AArch64::X1)
430                           .addReg(AArch64::SP)
431                           .addImm(2));
432 
433     recordSled(CurSled, MI, SledKind::CUSTOM_EVENT, 2);
434   }
435 }
436 
437 void AArch64AsmPrinter::LowerKCFI_CHECK(const MachineInstr &MI) {
438   Register AddrReg = MI.getOperand(0).getReg();
439   assert(std::next(MI.getIterator())->isCall() &&
440          "KCFI_CHECK not followed by a call instruction");
441   assert(std::next(MI.getIterator())->getOperand(0).getReg() == AddrReg &&
442          "KCFI_CHECK call target doesn't match call operand");
443 
444   // Default to using the intra-procedure-call temporary registers for
445   // comparing the hashes.
446   unsigned ScratchRegs[] = {AArch64::W16, AArch64::W17};
447   if (AddrReg == AArch64::XZR) {
448     // Checking XZR makes no sense. Instead of emitting a load, zero
449     // ScratchRegs[0] and use it for the ESR AddrIndex below.
450     AddrReg = getXRegFromWReg(ScratchRegs[0]);
451     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::ORRXrs)
452                                      .addReg(AddrReg)
453                                      .addReg(AArch64::XZR)
454                                      .addReg(AArch64::XZR)
455                                      .addImm(0));
456   } else {
457     // If one of the scratch registers is used for the call target (e.g.
458     // with AArch64::TCRETURNriBTI), we can clobber another caller-saved
459     // temporary register instead (in this case, AArch64::W9) as the check
460     // is immediately followed by the call instruction.
461     for (auto &Reg : ScratchRegs) {
462       if (Reg == getWRegFromXReg(AddrReg)) {
463         Reg = AArch64::W9;
464         break;
465       }
466     }
467     assert(ScratchRegs[0] != AddrReg && ScratchRegs[1] != AddrReg &&
468            "Invalid scratch registers for KCFI_CHECK");
469 
470     // Adjust the offset for patchable-function-prefix. This assumes that
471     // patchable-function-prefix is the same for all functions.
472     int64_t PrefixNops = 0;
473     (void)MI.getMF()
474         ->getFunction()
475         .getFnAttribute("patchable-function-prefix")
476         .getValueAsString()
477         .getAsInteger(10, PrefixNops);
478 
479     // Load the target function type hash.
480     EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::LDURWi)
481                                      .addReg(ScratchRegs[0])
482                                      .addReg(AddrReg)
483                                      .addImm(-(PrefixNops * 4 + 4)));
484   }
485 
486   // Load the expected type hash.
487   const int64_t Type = MI.getOperand(1).getImm();
488   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::MOVKWi)
489                                    .addReg(ScratchRegs[1])
490                                    .addReg(ScratchRegs[1])
491                                    .addImm(Type & 0xFFFF)
492                                    .addImm(0));
493   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::MOVKWi)
494                                    .addReg(ScratchRegs[1])
495                                    .addReg(ScratchRegs[1])
496                                    .addImm((Type >> 16) & 0xFFFF)
497                                    .addImm(16));
498 
499   // Compare the hashes and trap if there's a mismatch.
500   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::SUBSWrs)
501                                    .addReg(AArch64::WZR)
502                                    .addReg(ScratchRegs[0])
503                                    .addReg(ScratchRegs[1])
504                                    .addImm(0));
505 
506   MCSymbol *Pass = OutContext.createTempSymbol();
507   EmitToStreamer(*OutStreamer,
508                  MCInstBuilder(AArch64::Bcc)
509                      .addImm(AArch64CC::EQ)
510                      .addExpr(MCSymbolRefExpr::create(Pass, OutContext)));
511 
512   // The base ESR is 0x8000 and the register information is encoded in bits
513   // 0-9 as follows:
514   // - 0-4: n, where the register Xn contains the target address
515   // - 5-9: m, where the register Wm contains the expected type hash
516   // Where n, m are in [0, 30].
517   unsigned TypeIndex = ScratchRegs[1] - AArch64::W0;
518   unsigned AddrIndex;
519   switch (AddrReg) {
520   default:
521     AddrIndex = AddrReg - AArch64::X0;
522     break;
523   case AArch64::FP:
524     AddrIndex = 29;
525     break;
526   case AArch64::LR:
527     AddrIndex = 30;
528     break;
529   }
530 
531   assert(AddrIndex < 31 && TypeIndex < 31);
532 
533   unsigned ESR = 0x8000 | ((TypeIndex & 31) << 5) | (AddrIndex & 31);
534   EmitToStreamer(*OutStreamer, MCInstBuilder(AArch64::BRK).addImm(ESR));
535   OutStreamer->emitLabel(Pass);
536 }
537 
538 void AArch64AsmPrinter::LowerHWASAN_CHECK_MEMACCESS(const MachineInstr &MI) {
539   Register Reg = MI.getOperand(0).getReg();
540   bool IsShort =
541       MI.getOpcode() == AArch64::HWASAN_CHECK_MEMACCESS_SHORTGRANULES;
542   uint32_t AccessInfo = MI.getOperand(1).getImm();
543   MCSymbol *&Sym =
544       HwasanMemaccessSymbols[HwasanMemaccessTuple(Reg, IsShort, AccessInfo)];
545   if (!Sym) {
546     // FIXME: Make this work on non-ELF.
547     if (!TM.getTargetTriple().isOSBinFormatELF())
548       report_fatal_error("llvm.hwasan.check.memaccess only supported on ELF");
549 
550     std::string SymName = "__hwasan_check_x" + utostr(Reg - AArch64::X0) + "_" +
551                           utostr(AccessInfo);
552     if (IsShort)
553       SymName += "_short_v2";
554     Sym = OutContext.getOrCreateSymbol(SymName);
555   }
556 
557   EmitToStreamer(*OutStreamer,
558                  MCInstBuilder(AArch64::BL)
559                      .addExpr(MCSymbolRefExpr::create(Sym, OutContext)));
560 }
561 
562 void AArch64AsmPrinter::emitHwasanMemaccessSymbols(Module &M) {
563   if (HwasanMemaccessSymbols.empty())
564     return;
565 
566   const Triple &TT = TM.getTargetTriple();
567   assert(TT.isOSBinFormatELF());
568   std::unique_ptr<MCSubtargetInfo> STI(
569       TM.getTarget().createMCSubtargetInfo(TT.str(), "", ""));
570   assert(STI && "Unable to create subtarget info");
571 
572   MCSymbol *HwasanTagMismatchV1Sym =
573       OutContext.getOrCreateSymbol("__hwasan_tag_mismatch");
574   MCSymbol *HwasanTagMismatchV2Sym =
575       OutContext.getOrCreateSymbol("__hwasan_tag_mismatch_v2");
576 
577   const MCSymbolRefExpr *HwasanTagMismatchV1Ref =
578       MCSymbolRefExpr::create(HwasanTagMismatchV1Sym, OutContext);
579   const MCSymbolRefExpr *HwasanTagMismatchV2Ref =
580       MCSymbolRefExpr::create(HwasanTagMismatchV2Sym, OutContext);
581 
582   for (auto &P : HwasanMemaccessSymbols) {
583     unsigned Reg = std::get<0>(P.first);
584     bool IsShort = std::get<1>(P.first);
585     uint32_t AccessInfo = std::get<2>(P.first);
586     const MCSymbolRefExpr *HwasanTagMismatchRef =
587         IsShort ? HwasanTagMismatchV2Ref : HwasanTagMismatchV1Ref;
588     MCSymbol *Sym = P.second;
589 
590     bool HasMatchAllTag =
591         (AccessInfo >> HWASanAccessInfo::HasMatchAllShift) & 1;
592     uint8_t MatchAllTag =
593         (AccessInfo >> HWASanAccessInfo::MatchAllShift) & 0xff;
594     unsigned Size =
595         1 << ((AccessInfo >> HWASanAccessInfo::AccessSizeShift) & 0xf);
596     bool CompileKernel =
597         (AccessInfo >> HWASanAccessInfo::CompileKernelShift) & 1;
598 
599     OutStreamer->switchSection(OutContext.getELFSection(
600         ".text.hot", ELF::SHT_PROGBITS,
601         ELF::SHF_EXECINSTR | ELF::SHF_ALLOC | ELF::SHF_GROUP, 0, Sym->getName(),
602         /*IsComdat=*/true));
603 
604     OutStreamer->emitSymbolAttribute(Sym, MCSA_ELF_TypeFunction);
605     OutStreamer->emitSymbolAttribute(Sym, MCSA_Weak);
606     OutStreamer->emitSymbolAttribute(Sym, MCSA_Hidden);
607     OutStreamer->emitLabel(Sym);
608 
609     OutStreamer->emitInstruction(MCInstBuilder(AArch64::SBFMXri)
610                                      .addReg(AArch64::X16)
611                                      .addReg(Reg)
612                                      .addImm(4)
613                                      .addImm(55),
614                                  *STI);
615     OutStreamer->emitInstruction(
616         MCInstBuilder(AArch64::LDRBBroX)
617             .addReg(AArch64::W16)
618             .addReg(IsShort ? AArch64::X20 : AArch64::X9)
619             .addReg(AArch64::X16)
620             .addImm(0)
621             .addImm(0),
622         *STI);
623     OutStreamer->emitInstruction(
624         MCInstBuilder(AArch64::SUBSXrs)
625             .addReg(AArch64::XZR)
626             .addReg(AArch64::X16)
627             .addReg(Reg)
628             .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSR, 56)),
629         *STI);
630     MCSymbol *HandleMismatchOrPartialSym = OutContext.createTempSymbol();
631     OutStreamer->emitInstruction(
632         MCInstBuilder(AArch64::Bcc)
633             .addImm(AArch64CC::NE)
634             .addExpr(MCSymbolRefExpr::create(HandleMismatchOrPartialSym,
635                                              OutContext)),
636         *STI);
637     MCSymbol *ReturnSym = OutContext.createTempSymbol();
638     OutStreamer->emitLabel(ReturnSym);
639     OutStreamer->emitInstruction(
640         MCInstBuilder(AArch64::RET).addReg(AArch64::LR), *STI);
641     OutStreamer->emitLabel(HandleMismatchOrPartialSym);
642 
643     if (HasMatchAllTag) {
644       OutStreamer->emitInstruction(MCInstBuilder(AArch64::UBFMXri)
645                                        .addReg(AArch64::X17)
646                                        .addReg(Reg)
647                                        .addImm(56)
648                                        .addImm(63),
649                                    *STI);
650       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSXri)
651                                        .addReg(AArch64::XZR)
652                                        .addReg(AArch64::X17)
653                                        .addImm(MatchAllTag)
654                                        .addImm(0),
655                                    *STI);
656       OutStreamer->emitInstruction(
657           MCInstBuilder(AArch64::Bcc)
658               .addImm(AArch64CC::EQ)
659               .addExpr(MCSymbolRefExpr::create(ReturnSym, OutContext)),
660           *STI);
661     }
662 
663     if (IsShort) {
664       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSWri)
665                                        .addReg(AArch64::WZR)
666                                        .addReg(AArch64::W16)
667                                        .addImm(15)
668                                        .addImm(0),
669                                    *STI);
670       MCSymbol *HandleMismatchSym = OutContext.createTempSymbol();
671       OutStreamer->emitInstruction(
672           MCInstBuilder(AArch64::Bcc)
673               .addImm(AArch64CC::HI)
674               .addExpr(MCSymbolRefExpr::create(HandleMismatchSym, OutContext)),
675           *STI);
676 
677       OutStreamer->emitInstruction(
678           MCInstBuilder(AArch64::ANDXri)
679               .addReg(AArch64::X17)
680               .addReg(Reg)
681               .addImm(AArch64_AM::encodeLogicalImmediate(0xf, 64)),
682           *STI);
683       if (Size != 1)
684         OutStreamer->emitInstruction(MCInstBuilder(AArch64::ADDXri)
685                                          .addReg(AArch64::X17)
686                                          .addReg(AArch64::X17)
687                                          .addImm(Size - 1)
688                                          .addImm(0),
689                                      *STI);
690       OutStreamer->emitInstruction(MCInstBuilder(AArch64::SUBSWrs)
691                                        .addReg(AArch64::WZR)
692                                        .addReg(AArch64::W16)
693                                        .addReg(AArch64::W17)
694                                        .addImm(0),
695                                    *STI);
696       OutStreamer->emitInstruction(
697           MCInstBuilder(AArch64::Bcc)
698               .addImm(AArch64CC::LS)
699               .addExpr(MCSymbolRefExpr::create(HandleMismatchSym, OutContext)),
700           *STI);
701 
702       OutStreamer->emitInstruction(
703           MCInstBuilder(AArch64::ORRXri)
704               .addReg(AArch64::X16)
705               .addReg(Reg)
706               .addImm(AArch64_AM::encodeLogicalImmediate(0xf, 64)),
707           *STI);
708       OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDRBBui)
709                                        .addReg(AArch64::W16)
710                                        .addReg(AArch64::X16)
711                                        .addImm(0),
712                                    *STI);
713       OutStreamer->emitInstruction(
714           MCInstBuilder(AArch64::SUBSXrs)
715               .addReg(AArch64::XZR)
716               .addReg(AArch64::X16)
717               .addReg(Reg)
718               .addImm(AArch64_AM::getShifterImm(AArch64_AM::LSR, 56)),
719           *STI);
720       OutStreamer->emitInstruction(
721           MCInstBuilder(AArch64::Bcc)
722               .addImm(AArch64CC::EQ)
723               .addExpr(MCSymbolRefExpr::create(ReturnSym, OutContext)),
724           *STI);
725 
726       OutStreamer->emitLabel(HandleMismatchSym);
727     }
728 
729     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXpre)
730                                      .addReg(AArch64::SP)
731                                      .addReg(AArch64::X0)
732                                      .addReg(AArch64::X1)
733                                      .addReg(AArch64::SP)
734                                      .addImm(-32),
735                                  *STI);
736     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXi)
737                                      .addReg(AArch64::FP)
738                                      .addReg(AArch64::LR)
739                                      .addReg(AArch64::SP)
740                                      .addImm(29),
741                                  *STI);
742 
743     if (Reg != AArch64::X0)
744       OutStreamer->emitInstruction(MCInstBuilder(AArch64::ORRXrs)
745                                        .addReg(AArch64::X0)
746                                        .addReg(AArch64::XZR)
747                                        .addReg(Reg)
748                                        .addImm(0),
749                                    *STI);
750     OutStreamer->emitInstruction(
751         MCInstBuilder(AArch64::MOVZXi)
752             .addReg(AArch64::X1)
753             .addImm(AccessInfo & HWASanAccessInfo::RuntimeMask)
754             .addImm(0),
755         *STI);
756 
757     if (CompileKernel) {
758       // The Linux kernel's dynamic loader doesn't support GOT relative
759       // relocations, but it doesn't support late binding either, so just call
760       // the function directly.
761       OutStreamer->emitInstruction(
762           MCInstBuilder(AArch64::B).addExpr(HwasanTagMismatchRef), *STI);
763     } else {
764       // Intentionally load the GOT entry and branch to it, rather than possibly
765       // late binding the function, which may clobber the registers before we
766       // have a chance to save them.
767       OutStreamer->emitInstruction(
768           MCInstBuilder(AArch64::ADRP)
769               .addReg(AArch64::X16)
770               .addExpr(AArch64MCExpr::create(
771                   HwasanTagMismatchRef, AArch64MCExpr::VariantKind::VK_GOT_PAGE,
772                   OutContext)),
773           *STI);
774       OutStreamer->emitInstruction(
775           MCInstBuilder(AArch64::LDRXui)
776               .addReg(AArch64::X16)
777               .addReg(AArch64::X16)
778               .addExpr(AArch64MCExpr::create(
779                   HwasanTagMismatchRef, AArch64MCExpr::VariantKind::VK_GOT_LO12,
780                   OutContext)),
781           *STI);
782       OutStreamer->emitInstruction(
783           MCInstBuilder(AArch64::BR).addReg(AArch64::X16), *STI);
784     }
785   }
786 }
787 
788 void AArch64AsmPrinter::emitEndOfAsmFile(Module &M) {
789   emitHwasanMemaccessSymbols(M);
790 
791   const Triple &TT = TM.getTargetTriple();
792   if (TT.isOSBinFormatMachO()) {
793     // Funny Darwin hack: This flag tells the linker that no global symbols
794     // contain code that falls through to other global symbols (e.g. the obvious
795     // implementation of multiple entry points).  If this doesn't occur, the
796     // linker can safely perform dead code stripping.  Since LLVM never
797     // generates code that does this, it is always safe to set.
798     OutStreamer->emitAssemblerFlag(MCAF_SubsectionsViaSymbols);
799   }
800 
801   // Emit stack and fault map information.
802   FM.serializeToFaultMapSection();
803 
804 }
805 
806 void AArch64AsmPrinter::emitLOHs() {
807   SmallVector<MCSymbol *, 3> MCArgs;
808 
809   for (const auto &D : AArch64FI->getLOHContainer()) {
810     for (const MachineInstr *MI : D.getArgs()) {
811       MInstToMCSymbol::iterator LabelIt = LOHInstToLabel.find(MI);
812       assert(LabelIt != LOHInstToLabel.end() &&
813              "Label hasn't been inserted for LOH related instruction");
814       MCArgs.push_back(LabelIt->second);
815     }
816     OutStreamer->emitLOHDirective(D.getKind(), MCArgs);
817     MCArgs.clear();
818   }
819 }
820 
821 void AArch64AsmPrinter::emitFunctionBodyEnd() {
822   if (!AArch64FI->getLOHRelated().empty())
823     emitLOHs();
824 }
825 
826 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
827 MCSymbol *AArch64AsmPrinter::GetCPISymbol(unsigned CPID) const {
828   // Darwin uses a linker-private symbol name for constant-pools (to
829   // avoid addends on the relocation?), ELF has no such concept and
830   // uses a normal private symbol.
831   if (!getDataLayout().getLinkerPrivateGlobalPrefix().empty())
832     return OutContext.getOrCreateSymbol(
833         Twine(getDataLayout().getLinkerPrivateGlobalPrefix()) + "CPI" +
834         Twine(getFunctionNumber()) + "_" + Twine(CPID));
835 
836   return AsmPrinter::GetCPISymbol(CPID);
837 }
838 
839 void AArch64AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNum,
840                                      raw_ostream &O) {
841   const MachineOperand &MO = MI->getOperand(OpNum);
842   switch (MO.getType()) {
843   default:
844     llvm_unreachable("<unknown operand type>");
845   case MachineOperand::MO_Register: {
846     Register Reg = MO.getReg();
847     assert(Reg.isPhysical());
848     assert(!MO.getSubReg() && "Subregs should be eliminated!");
849     O << AArch64InstPrinter::getRegisterName(Reg);
850     break;
851   }
852   case MachineOperand::MO_Immediate: {
853     O << MO.getImm();
854     break;
855   }
856   case MachineOperand::MO_GlobalAddress: {
857     PrintSymbolOperand(MO, O);
858     break;
859   }
860   case MachineOperand::MO_BlockAddress: {
861     MCSymbol *Sym = GetBlockAddressSymbol(MO.getBlockAddress());
862     Sym->print(O, MAI);
863     break;
864   }
865   }
866 }
867 
868 bool AArch64AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
869                                           raw_ostream &O) {
870   Register Reg = MO.getReg();
871   switch (Mode) {
872   default:
873     return true; // Unknown mode.
874   case 'w':
875     Reg = getWRegFromXReg(Reg);
876     break;
877   case 'x':
878     Reg = getXRegFromWReg(Reg);
879     break;
880   case 't':
881     Reg = getXRegFromXRegTuple(Reg);
882     break;
883   }
884 
885   O << AArch64InstPrinter::getRegisterName(Reg);
886   return false;
887 }
888 
889 // Prints the register in MO using class RC using the offset in the
890 // new register class. This should not be used for cross class
891 // printing.
892 bool AArch64AsmPrinter::printAsmRegInClass(const MachineOperand &MO,
893                                            const TargetRegisterClass *RC,
894                                            unsigned AltName, raw_ostream &O) {
895   assert(MO.isReg() && "Should only get here with a register!");
896   const TargetRegisterInfo *RI = STI->getRegisterInfo();
897   Register Reg = MO.getReg();
898   unsigned RegToPrint = RC->getRegister(RI->getEncodingValue(Reg));
899   if (!RI->regsOverlap(RegToPrint, Reg))
900     return true;
901   O << AArch64InstPrinter::getRegisterName(RegToPrint, AltName);
902   return false;
903 }
904 
905 bool AArch64AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
906                                         const char *ExtraCode, raw_ostream &O) {
907   const MachineOperand &MO = MI->getOperand(OpNum);
908 
909   // First try the generic code, which knows about modifiers like 'c' and 'n'.
910   if (!AsmPrinter::PrintAsmOperand(MI, OpNum, ExtraCode, O))
911     return false;
912 
913   // Does this asm operand have a single letter operand modifier?
914   if (ExtraCode && ExtraCode[0]) {
915     if (ExtraCode[1] != 0)
916       return true; // Unknown modifier.
917 
918     switch (ExtraCode[0]) {
919     default:
920       return true; // Unknown modifier.
921     case 'w':      // Print W register
922     case 'x':      // Print X register
923       if (MO.isReg())
924         return printAsmMRegister(MO, ExtraCode[0], O);
925       if (MO.isImm() && MO.getImm() == 0) {
926         unsigned Reg = ExtraCode[0] == 'w' ? AArch64::WZR : AArch64::XZR;
927         O << AArch64InstPrinter::getRegisterName(Reg);
928         return false;
929       }
930       printOperand(MI, OpNum, O);
931       return false;
932     case 'b': // Print B register.
933     case 'h': // Print H register.
934     case 's': // Print S register.
935     case 'd': // Print D register.
936     case 'q': // Print Q register.
937     case 'z': // Print Z register.
938       if (MO.isReg()) {
939         const TargetRegisterClass *RC;
940         switch (ExtraCode[0]) {
941         case 'b':
942           RC = &AArch64::FPR8RegClass;
943           break;
944         case 'h':
945           RC = &AArch64::FPR16RegClass;
946           break;
947         case 's':
948           RC = &AArch64::FPR32RegClass;
949           break;
950         case 'd':
951           RC = &AArch64::FPR64RegClass;
952           break;
953         case 'q':
954           RC = &AArch64::FPR128RegClass;
955           break;
956         case 'z':
957           RC = &AArch64::ZPRRegClass;
958           break;
959         default:
960           return true;
961         }
962         return printAsmRegInClass(MO, RC, AArch64::NoRegAltName, O);
963       }
964       printOperand(MI, OpNum, O);
965       return false;
966     }
967   }
968 
969   // According to ARM, we should emit x and v registers unless we have a
970   // modifier.
971   if (MO.isReg()) {
972     Register Reg = MO.getReg();
973 
974     // If this is a w or x register, print an x register.
975     if (AArch64::GPR32allRegClass.contains(Reg) ||
976         AArch64::GPR64allRegClass.contains(Reg))
977       return printAsmMRegister(MO, 'x', O);
978 
979     // If this is an x register tuple, print an x register.
980     if (AArch64::GPR64x8ClassRegClass.contains(Reg))
981       return printAsmMRegister(MO, 't', O);
982 
983     unsigned AltName = AArch64::NoRegAltName;
984     const TargetRegisterClass *RegClass;
985     if (AArch64::ZPRRegClass.contains(Reg)) {
986       RegClass = &AArch64::ZPRRegClass;
987     } else if (AArch64::PPRRegClass.contains(Reg)) {
988       RegClass = &AArch64::PPRRegClass;
989     } else if (AArch64::PNRRegClass.contains(Reg)) {
990       RegClass = &AArch64::PNRRegClass;
991     } else {
992       RegClass = &AArch64::FPR128RegClass;
993       AltName = AArch64::vreg;
994     }
995 
996     // If this is a b, h, s, d, or q register, print it as a v register.
997     return printAsmRegInClass(MO, RegClass, AltName, O);
998   }
999 
1000   printOperand(MI, OpNum, O);
1001   return false;
1002 }
1003 
1004 bool AArch64AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
1005                                               unsigned OpNum,
1006                                               const char *ExtraCode,
1007                                               raw_ostream &O) {
1008   if (ExtraCode && ExtraCode[0] && ExtraCode[0] != 'a')
1009     return true; // Unknown modifier.
1010 
1011   const MachineOperand &MO = MI->getOperand(OpNum);
1012   assert(MO.isReg() && "unexpected inline asm memory operand");
1013   O << "[" << AArch64InstPrinter::getRegisterName(MO.getReg()) << "]";
1014   return false;
1015 }
1016 
1017 void AArch64AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
1018                                                raw_ostream &OS) {
1019   unsigned NOps = MI->getNumOperands();
1020   assert(NOps == 4);
1021   OS << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
1022   // cast away const; DIetc do not take const operands for some reason.
1023   OS << MI->getDebugVariable()->getName();
1024   OS << " <- ";
1025   // Frame address.  Currently handles register +- offset only.
1026   assert(MI->isIndirectDebugValue());
1027   OS << '[';
1028   for (unsigned I = 0, E = std::distance(MI->debug_operands().begin(),
1029                                          MI->debug_operands().end());
1030        I < E; ++I) {
1031     if (I != 0)
1032       OS << ", ";
1033     printOperand(MI, I, OS);
1034   }
1035   OS << ']';
1036   OS << "+";
1037   printOperand(MI, NOps - 2, OS);
1038 }
1039 
1040 void AArch64AsmPrinter::emitJumpTableInfo() {
1041   const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1042   if (!MJTI) return;
1043 
1044   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1045   if (JT.empty()) return;
1046 
1047   const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1048   MCSection *ReadOnlySec = TLOF.getSectionForJumpTable(MF->getFunction(), TM);
1049   OutStreamer->switchSection(ReadOnlySec);
1050 
1051   auto AFI = MF->getInfo<AArch64FunctionInfo>();
1052   for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1053     const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1054 
1055     // If this jump table was deleted, ignore it.
1056     if (JTBBs.empty()) continue;
1057 
1058     unsigned Size = AFI->getJumpTableEntrySize(JTI);
1059     emitAlignment(Align(Size));
1060     OutStreamer->emitLabel(GetJTISymbol(JTI));
1061 
1062     const MCSymbol *BaseSym = AArch64FI->getJumpTableEntryPCRelSymbol(JTI);
1063     const MCExpr *Base = MCSymbolRefExpr::create(BaseSym, OutContext);
1064 
1065     for (auto *JTBB : JTBBs) {
1066       const MCExpr *Value =
1067           MCSymbolRefExpr::create(JTBB->getSymbol(), OutContext);
1068 
1069       // Each entry is:
1070       //     .byte/.hword (LBB - Lbase)>>2
1071       // or plain:
1072       //     .word LBB - Lbase
1073       Value = MCBinaryExpr::createSub(Value, Base, OutContext);
1074       if (Size != 4)
1075         Value = MCBinaryExpr::createLShr(
1076             Value, MCConstantExpr::create(2, OutContext), OutContext);
1077 
1078       OutStreamer->emitValue(Value, Size);
1079     }
1080   }
1081 }
1082 
1083 std::tuple<const MCSymbol *, uint64_t, const MCSymbol *,
1084            codeview::JumpTableEntrySize>
1085 AArch64AsmPrinter::getCodeViewJumpTableInfo(int JTI,
1086                                             const MachineInstr *BranchInstr,
1087                                             const MCSymbol *BranchLabel) const {
1088   const auto AFI = MF->getInfo<AArch64FunctionInfo>();
1089   const auto Base = AArch64FI->getJumpTableEntryPCRelSymbol(JTI);
1090   codeview::JumpTableEntrySize EntrySize;
1091   switch (AFI->getJumpTableEntrySize(JTI)) {
1092   case 1:
1093     EntrySize = codeview::JumpTableEntrySize::UInt8ShiftLeft;
1094     break;
1095   case 2:
1096     EntrySize = codeview::JumpTableEntrySize::UInt16ShiftLeft;
1097     break;
1098   case 4:
1099     EntrySize = codeview::JumpTableEntrySize::Int32;
1100     break;
1101   default:
1102     llvm_unreachable("Unexpected jump table entry size");
1103   }
1104   return std::make_tuple(Base, 0, BranchLabel, EntrySize);
1105 }
1106 
1107 void AArch64AsmPrinter::emitFunctionEntryLabel() {
1108   if (MF->getFunction().getCallingConv() == CallingConv::AArch64_VectorCall ||
1109       MF->getFunction().getCallingConv() ==
1110           CallingConv::AArch64_SVE_VectorCall ||
1111       MF->getInfo<AArch64FunctionInfo>()->isSVECC()) {
1112     auto *TS =
1113         static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
1114     TS->emitDirectiveVariantPCS(CurrentFnSym);
1115   }
1116 
1117   return AsmPrinter::emitFunctionEntryLabel();
1118 }
1119 
1120 /// Small jump tables contain an unsigned byte or half, representing the offset
1121 /// from the lowest-addressed possible destination to the desired basic
1122 /// block. Since all instructions are 4-byte aligned, this is further compressed
1123 /// by counting in instructions rather than bytes (i.e. divided by 4). So, to
1124 /// materialize the correct destination we need:
1125 ///
1126 ///             adr xDest, .LBB0_0
1127 ///             ldrb wScratch, [xTable, xEntry]   (with "lsl #1" for ldrh).
1128 ///             add xDest, xDest, xScratch (with "lsl #2" for smaller entries)
1129 void AArch64AsmPrinter::LowerJumpTableDest(llvm::MCStreamer &OutStreamer,
1130                                            const llvm::MachineInstr &MI) {
1131   Register DestReg = MI.getOperand(0).getReg();
1132   Register ScratchReg = MI.getOperand(1).getReg();
1133   Register ScratchRegW =
1134       STI->getRegisterInfo()->getSubReg(ScratchReg, AArch64::sub_32);
1135   Register TableReg = MI.getOperand(2).getReg();
1136   Register EntryReg = MI.getOperand(3).getReg();
1137   int JTIdx = MI.getOperand(4).getIndex();
1138   int Size = AArch64FI->getJumpTableEntrySize(JTIdx);
1139 
1140   // This has to be first because the compression pass based its reachability
1141   // calculations on the start of the JumpTableDest instruction.
1142   auto Label =
1143       MF->getInfo<AArch64FunctionInfo>()->getJumpTableEntryPCRelSymbol(JTIdx);
1144 
1145   // If we don't already have a symbol to use as the base, use the ADR
1146   // instruction itself.
1147   if (!Label) {
1148     Label = MF->getContext().createTempSymbol();
1149     AArch64FI->setJumpTableEntryInfo(JTIdx, Size, Label);
1150     OutStreamer.emitLabel(Label);
1151   }
1152 
1153   auto LabelExpr = MCSymbolRefExpr::create(Label, MF->getContext());
1154   EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::ADR)
1155                                   .addReg(DestReg)
1156                                   .addExpr(LabelExpr));
1157 
1158   // Load the number of instruction-steps to offset from the label.
1159   unsigned LdrOpcode;
1160   switch (Size) {
1161   case 1: LdrOpcode = AArch64::LDRBBroX; break;
1162   case 2: LdrOpcode = AArch64::LDRHHroX; break;
1163   case 4: LdrOpcode = AArch64::LDRSWroX; break;
1164   default:
1165     llvm_unreachable("Unknown jump table size");
1166   }
1167 
1168   EmitToStreamer(OutStreamer, MCInstBuilder(LdrOpcode)
1169                                   .addReg(Size == 4 ? ScratchReg : ScratchRegW)
1170                                   .addReg(TableReg)
1171                                   .addReg(EntryReg)
1172                                   .addImm(0)
1173                                   .addImm(Size == 1 ? 0 : 1));
1174 
1175   // Add to the already materialized base label address, multiplying by 4 if
1176   // compressed.
1177   EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::ADDXrs)
1178                                   .addReg(DestReg)
1179                                   .addReg(DestReg)
1180                                   .addReg(ScratchReg)
1181                                   .addImm(Size == 4 ? 0 : 2));
1182 }
1183 
1184 void AArch64AsmPrinter::LowerMOPS(llvm::MCStreamer &OutStreamer,
1185                                   const llvm::MachineInstr &MI) {
1186   unsigned Opcode = MI.getOpcode();
1187   assert(STI->hasMOPS());
1188   assert(STI->hasMTE() || Opcode != AArch64::MOPSMemorySetTaggingPseudo);
1189 
1190   const auto Ops = [Opcode]() -> std::array<unsigned, 3> {
1191     if (Opcode == AArch64::MOPSMemoryCopyPseudo)
1192       return {AArch64::CPYFP, AArch64::CPYFM, AArch64::CPYFE};
1193     if (Opcode == AArch64::MOPSMemoryMovePseudo)
1194       return {AArch64::CPYP, AArch64::CPYM, AArch64::CPYE};
1195     if (Opcode == AArch64::MOPSMemorySetPseudo)
1196       return {AArch64::SETP, AArch64::SETM, AArch64::SETE};
1197     if (Opcode == AArch64::MOPSMemorySetTaggingPseudo)
1198       return {AArch64::SETGP, AArch64::SETGM, AArch64::MOPSSETGE};
1199     llvm_unreachable("Unhandled memory operation pseudo");
1200   }();
1201   const bool IsSet = Opcode == AArch64::MOPSMemorySetPseudo ||
1202                      Opcode == AArch64::MOPSMemorySetTaggingPseudo;
1203 
1204   for (auto Op : Ops) {
1205     int i = 0;
1206     auto MCIB = MCInstBuilder(Op);
1207     // Destination registers
1208     MCIB.addReg(MI.getOperand(i++).getReg());
1209     MCIB.addReg(MI.getOperand(i++).getReg());
1210     if (!IsSet)
1211       MCIB.addReg(MI.getOperand(i++).getReg());
1212     // Input registers
1213     MCIB.addReg(MI.getOperand(i++).getReg());
1214     MCIB.addReg(MI.getOperand(i++).getReg());
1215     MCIB.addReg(MI.getOperand(i++).getReg());
1216 
1217     EmitToStreamer(OutStreamer, MCIB);
1218   }
1219 }
1220 
1221 void AArch64AsmPrinter::LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM,
1222                                       const MachineInstr &MI) {
1223   unsigned NumNOPBytes = StackMapOpers(&MI).getNumPatchBytes();
1224 
1225   auto &Ctx = OutStreamer.getContext();
1226   MCSymbol *MILabel = Ctx.createTempSymbol();
1227   OutStreamer.emitLabel(MILabel);
1228 
1229   SM.recordStackMap(*MILabel, MI);
1230   assert(NumNOPBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
1231 
1232   // Scan ahead to trim the shadow.
1233   const MachineBasicBlock &MBB = *MI.getParent();
1234   MachineBasicBlock::const_iterator MII(MI);
1235   ++MII;
1236   while (NumNOPBytes > 0) {
1237     if (MII == MBB.end() || MII->isCall() ||
1238         MII->getOpcode() == AArch64::DBG_VALUE ||
1239         MII->getOpcode() == TargetOpcode::PATCHPOINT ||
1240         MII->getOpcode() == TargetOpcode::STACKMAP)
1241       break;
1242     ++MII;
1243     NumNOPBytes -= 4;
1244   }
1245 
1246   // Emit nops.
1247   for (unsigned i = 0; i < NumNOPBytes; i += 4)
1248     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1249 }
1250 
1251 // Lower a patchpoint of the form:
1252 // [<def>], <id>, <numBytes>, <target>, <numArgs>
1253 void AArch64AsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM,
1254                                         const MachineInstr &MI) {
1255   auto &Ctx = OutStreamer.getContext();
1256   MCSymbol *MILabel = Ctx.createTempSymbol();
1257   OutStreamer.emitLabel(MILabel);
1258   SM.recordPatchPoint(*MILabel, MI);
1259 
1260   PatchPointOpers Opers(&MI);
1261 
1262   int64_t CallTarget = Opers.getCallTarget().getImm();
1263   unsigned EncodedBytes = 0;
1264   if (CallTarget) {
1265     assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget &&
1266            "High 16 bits of call target should be zero.");
1267     Register ScratchReg = MI.getOperand(Opers.getNextScratchIdx()).getReg();
1268     EncodedBytes = 16;
1269     // Materialize the jump address:
1270     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVZXi)
1271                                     .addReg(ScratchReg)
1272                                     .addImm((CallTarget >> 32) & 0xFFFF)
1273                                     .addImm(32));
1274     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKXi)
1275                                     .addReg(ScratchReg)
1276                                     .addReg(ScratchReg)
1277                                     .addImm((CallTarget >> 16) & 0xFFFF)
1278                                     .addImm(16));
1279     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKXi)
1280                                     .addReg(ScratchReg)
1281                                     .addReg(ScratchReg)
1282                                     .addImm(CallTarget & 0xFFFF)
1283                                     .addImm(0));
1284     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::BLR).addReg(ScratchReg));
1285   }
1286   // Emit padding.
1287   unsigned NumBytes = Opers.getNumPatchBytes();
1288   assert(NumBytes >= EncodedBytes &&
1289          "Patchpoint can't request size less than the length of a call.");
1290   assert((NumBytes - EncodedBytes) % 4 == 0 &&
1291          "Invalid number of NOP bytes requested!");
1292   for (unsigned i = EncodedBytes; i < NumBytes; i += 4)
1293     EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1294 }
1295 
1296 void AArch64AsmPrinter::LowerSTATEPOINT(MCStreamer &OutStreamer, StackMaps &SM,
1297                                         const MachineInstr &MI) {
1298   StatepointOpers SOpers(&MI);
1299   if (unsigned PatchBytes = SOpers.getNumPatchBytes()) {
1300     assert(PatchBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
1301     for (unsigned i = 0; i < PatchBytes; i += 4)
1302       EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0));
1303   } else {
1304     // Lower call target and choose correct opcode
1305     const MachineOperand &CallTarget = SOpers.getCallTarget();
1306     MCOperand CallTargetMCOp;
1307     unsigned CallOpcode;
1308     switch (CallTarget.getType()) {
1309     case MachineOperand::MO_GlobalAddress:
1310     case MachineOperand::MO_ExternalSymbol:
1311       MCInstLowering.lowerOperand(CallTarget, CallTargetMCOp);
1312       CallOpcode = AArch64::BL;
1313       break;
1314     case MachineOperand::MO_Immediate:
1315       CallTargetMCOp = MCOperand::createImm(CallTarget.getImm());
1316       CallOpcode = AArch64::BL;
1317       break;
1318     case MachineOperand::MO_Register:
1319       CallTargetMCOp = MCOperand::createReg(CallTarget.getReg());
1320       CallOpcode = AArch64::BLR;
1321       break;
1322     default:
1323       llvm_unreachable("Unsupported operand type in statepoint call target");
1324       break;
1325     }
1326 
1327     EmitToStreamer(OutStreamer,
1328                    MCInstBuilder(CallOpcode).addOperand(CallTargetMCOp));
1329   }
1330 
1331   auto &Ctx = OutStreamer.getContext();
1332   MCSymbol *MILabel = Ctx.createTempSymbol();
1333   OutStreamer.emitLabel(MILabel);
1334   SM.recordStatepoint(*MILabel, MI);
1335 }
1336 
1337 void AArch64AsmPrinter::LowerFAULTING_OP(const MachineInstr &FaultingMI) {
1338   // FAULTING_LOAD_OP <def>, <faltinf type>, <MBB handler>,
1339   //                  <opcode>, <operands>
1340 
1341   Register DefRegister = FaultingMI.getOperand(0).getReg();
1342   FaultMaps::FaultKind FK =
1343       static_cast<FaultMaps::FaultKind>(FaultingMI.getOperand(1).getImm());
1344   MCSymbol *HandlerLabel = FaultingMI.getOperand(2).getMBB()->getSymbol();
1345   unsigned Opcode = FaultingMI.getOperand(3).getImm();
1346   unsigned OperandsBeginIdx = 4;
1347 
1348   auto &Ctx = OutStreamer->getContext();
1349   MCSymbol *FaultingLabel = Ctx.createTempSymbol();
1350   OutStreamer->emitLabel(FaultingLabel);
1351 
1352   assert(FK < FaultMaps::FaultKindMax && "Invalid Faulting Kind!");
1353   FM.recordFaultingOp(FK, FaultingLabel, HandlerLabel);
1354 
1355   MCInst MI;
1356   MI.setOpcode(Opcode);
1357 
1358   if (DefRegister != (Register)0)
1359     MI.addOperand(MCOperand::createReg(DefRegister));
1360 
1361   for (const MachineOperand &MO :
1362        llvm::drop_begin(FaultingMI.operands(), OperandsBeginIdx)) {
1363     MCOperand Dest;
1364     lowerOperand(MO, Dest);
1365     MI.addOperand(Dest);
1366   }
1367 
1368   OutStreamer->AddComment("on-fault: " + HandlerLabel->getName());
1369   OutStreamer->emitInstruction(MI, getSubtargetInfo());
1370 }
1371 
1372 void AArch64AsmPrinter::emitFMov0(const MachineInstr &MI) {
1373   Register DestReg = MI.getOperand(0).getReg();
1374   if (STI->hasZeroCycleZeroingFP() && !STI->hasZeroCycleZeroingFPWorkaround() &&
1375       STI->isNeonAvailable()) {
1376     // Convert H/S register to corresponding D register
1377     if (AArch64::H0 <= DestReg && DestReg <= AArch64::H31)
1378       DestReg = AArch64::D0 + (DestReg - AArch64::H0);
1379     else if (AArch64::S0 <= DestReg && DestReg <= AArch64::S31)
1380       DestReg = AArch64::D0 + (DestReg - AArch64::S0);
1381     else
1382       assert(AArch64::D0 <= DestReg && DestReg <= AArch64::D31);
1383 
1384     MCInst MOVI;
1385     MOVI.setOpcode(AArch64::MOVID);
1386     MOVI.addOperand(MCOperand::createReg(DestReg));
1387     MOVI.addOperand(MCOperand::createImm(0));
1388     EmitToStreamer(*OutStreamer, MOVI);
1389   } else {
1390     MCInst FMov;
1391     switch (MI.getOpcode()) {
1392     default: llvm_unreachable("Unexpected opcode");
1393     case AArch64::FMOVH0:
1394       FMov.setOpcode(STI->hasFullFP16() ? AArch64::FMOVWHr : AArch64::FMOVWSr);
1395       if (!STI->hasFullFP16())
1396         DestReg = (AArch64::S0 + (DestReg - AArch64::H0));
1397       FMov.addOperand(MCOperand::createReg(DestReg));
1398       FMov.addOperand(MCOperand::createReg(AArch64::WZR));
1399       break;
1400     case AArch64::FMOVS0:
1401       FMov.setOpcode(AArch64::FMOVWSr);
1402       FMov.addOperand(MCOperand::createReg(DestReg));
1403       FMov.addOperand(MCOperand::createReg(AArch64::WZR));
1404       break;
1405     case AArch64::FMOVD0:
1406       FMov.setOpcode(AArch64::FMOVXDr);
1407       FMov.addOperand(MCOperand::createReg(DestReg));
1408       FMov.addOperand(MCOperand::createReg(AArch64::XZR));
1409       break;
1410     }
1411     EmitToStreamer(*OutStreamer, FMov);
1412   }
1413 }
1414 
1415 // Simple pseudo-instructions have their lowering (with expansion to real
1416 // instructions) auto-generated.
1417 #include "AArch64GenMCPseudoLowering.inc"
1418 
1419 void AArch64AsmPrinter::emitInstruction(const MachineInstr *MI) {
1420   AArch64_MC::verifyInstructionPredicates(MI->getOpcode(), STI->getFeatureBits());
1421 
1422   // Do any auto-generated pseudo lowerings.
1423   if (emitPseudoExpansionLowering(*OutStreamer, MI))
1424     return;
1425 
1426   if (MI->getOpcode() == AArch64::ADRP) {
1427     for (auto &Opd : MI->operands()) {
1428       if (Opd.isSymbol() && StringRef(Opd.getSymbolName()) ==
1429                                 "swift_async_extendedFramePointerFlags") {
1430         ShouldEmitWeakSwiftAsyncExtendedFramePointerFlags = true;
1431       }
1432     }
1433   }
1434 
1435   if (AArch64FI->getLOHRelated().count(MI)) {
1436     // Generate a label for LOH related instruction
1437     MCSymbol *LOHLabel = createTempSymbol("loh");
1438     // Associate the instruction with the label
1439     LOHInstToLabel[MI] = LOHLabel;
1440     OutStreamer->emitLabel(LOHLabel);
1441   }
1442 
1443   AArch64TargetStreamer *TS =
1444     static_cast<AArch64TargetStreamer *>(OutStreamer->getTargetStreamer());
1445   // Do any manual lowerings.
1446   switch (MI->getOpcode()) {
1447   default:
1448     break;
1449   case AArch64::HINT: {
1450     // CurrentPatchableFunctionEntrySym can be CurrentFnBegin only for
1451     // -fpatchable-function-entry=N,0. The entry MBB is guaranteed to be
1452     // non-empty. If MI is the initial BTI, place the
1453     // __patchable_function_entries label after BTI.
1454     if (CurrentPatchableFunctionEntrySym &&
1455         CurrentPatchableFunctionEntrySym == CurrentFnBegin &&
1456         MI == &MF->front().front()) {
1457       int64_t Imm = MI->getOperand(0).getImm();
1458       if ((Imm & 32) && (Imm & 6)) {
1459         MCInst Inst;
1460         MCInstLowering.Lower(MI, Inst);
1461         EmitToStreamer(*OutStreamer, Inst);
1462         CurrentPatchableFunctionEntrySym = createTempSymbol("patch");
1463         OutStreamer->emitLabel(CurrentPatchableFunctionEntrySym);
1464         return;
1465       }
1466     }
1467     break;
1468   }
1469     case AArch64::MOVMCSym: {
1470       Register DestReg = MI->getOperand(0).getReg();
1471       const MachineOperand &MO_Sym = MI->getOperand(1);
1472       MachineOperand Hi_MOSym(MO_Sym), Lo_MOSym(MO_Sym);
1473       MCOperand Hi_MCSym, Lo_MCSym;
1474 
1475       Hi_MOSym.setTargetFlags(AArch64II::MO_G1 | AArch64II::MO_S);
1476       Lo_MOSym.setTargetFlags(AArch64II::MO_G0 | AArch64II::MO_NC);
1477 
1478       MCInstLowering.lowerOperand(Hi_MOSym, Hi_MCSym);
1479       MCInstLowering.lowerOperand(Lo_MOSym, Lo_MCSym);
1480 
1481       MCInst MovZ;
1482       MovZ.setOpcode(AArch64::MOVZXi);
1483       MovZ.addOperand(MCOperand::createReg(DestReg));
1484       MovZ.addOperand(Hi_MCSym);
1485       MovZ.addOperand(MCOperand::createImm(16));
1486       EmitToStreamer(*OutStreamer, MovZ);
1487 
1488       MCInst MovK;
1489       MovK.setOpcode(AArch64::MOVKXi);
1490       MovK.addOperand(MCOperand::createReg(DestReg));
1491       MovK.addOperand(MCOperand::createReg(DestReg));
1492       MovK.addOperand(Lo_MCSym);
1493       MovK.addOperand(MCOperand::createImm(0));
1494       EmitToStreamer(*OutStreamer, MovK);
1495       return;
1496   }
1497   case AArch64::MOVIv2d_ns:
1498     // It is generally beneficial to rewrite "fmov s0, wzr" to "movi d0, #0".
1499     // as movi is more efficient across all cores. Newer cores can eliminate
1500     // fmovs early and there is no difference with movi, but this not true for
1501     // all implementations.
1502     //
1503     // The floating-point version doesn't quite work in rare cases on older
1504     // CPUs, so on those targets we lower this instruction to movi.16b instead.
1505     if (STI->hasZeroCycleZeroingFPWorkaround() &&
1506         MI->getOperand(1).getImm() == 0) {
1507       MCInst TmpInst;
1508       TmpInst.setOpcode(AArch64::MOVIv16b_ns);
1509       TmpInst.addOperand(MCOperand::createReg(MI->getOperand(0).getReg()));
1510       TmpInst.addOperand(MCOperand::createImm(MI->getOperand(1).getImm()));
1511       EmitToStreamer(*OutStreamer, TmpInst);
1512       return;
1513     }
1514     break;
1515 
1516   case AArch64::DBG_VALUE:
1517   case AArch64::DBG_VALUE_LIST:
1518     if (isVerbose() && OutStreamer->hasRawTextSupport()) {
1519       SmallString<128> TmpStr;
1520       raw_svector_ostream OS(TmpStr);
1521       PrintDebugValueComment(MI, OS);
1522       OutStreamer->emitRawText(StringRef(OS.str()));
1523     }
1524     return;
1525 
1526   case AArch64::EMITBKEY: {
1527       ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
1528       if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1529           ExceptionHandlingType != ExceptionHandling::ARM)
1530         return;
1531 
1532       if (getFunctionCFISectionType(*MF) == CFISection::None)
1533         return;
1534 
1535       OutStreamer->emitCFIBKeyFrame();
1536       return;
1537   }
1538 
1539   case AArch64::EMITMTETAGGED: {
1540     ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
1541     if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1542         ExceptionHandlingType != ExceptionHandling::ARM)
1543       return;
1544 
1545     if (getFunctionCFISectionType(*MF) != CFISection::None)
1546       OutStreamer->emitCFIMTETaggedFrame();
1547     return;
1548   }
1549 
1550   // Tail calls use pseudo instructions so they have the proper code-gen
1551   // attributes (isCall, isReturn, etc.). We lower them to the real
1552   // instruction here.
1553   case AArch64::TCRETURNri:
1554   case AArch64::TCRETURNriBTI:
1555   case AArch64::TCRETURNriALL: {
1556     MCInst TmpInst;
1557     TmpInst.setOpcode(AArch64::BR);
1558     TmpInst.addOperand(MCOperand::createReg(MI->getOperand(0).getReg()));
1559     EmitToStreamer(*OutStreamer, TmpInst);
1560     return;
1561   }
1562   case AArch64::TCRETURNdi: {
1563     MCOperand Dest;
1564     MCInstLowering.lowerOperand(MI->getOperand(0), Dest);
1565     MCInst TmpInst;
1566     TmpInst.setOpcode(AArch64::B);
1567     TmpInst.addOperand(Dest);
1568     EmitToStreamer(*OutStreamer, TmpInst);
1569     return;
1570   }
1571   case AArch64::SpeculationBarrierISBDSBEndBB: {
1572     // Print DSB SYS + ISB
1573     MCInst TmpInstDSB;
1574     TmpInstDSB.setOpcode(AArch64::DSB);
1575     TmpInstDSB.addOperand(MCOperand::createImm(0xf));
1576     EmitToStreamer(*OutStreamer, TmpInstDSB);
1577     MCInst TmpInstISB;
1578     TmpInstISB.setOpcode(AArch64::ISB);
1579     TmpInstISB.addOperand(MCOperand::createImm(0xf));
1580     EmitToStreamer(*OutStreamer, TmpInstISB);
1581     return;
1582   }
1583   case AArch64::SpeculationBarrierSBEndBB: {
1584     // Print SB
1585     MCInst TmpInstSB;
1586     TmpInstSB.setOpcode(AArch64::SB);
1587     EmitToStreamer(*OutStreamer, TmpInstSB);
1588     return;
1589   }
1590   case AArch64::TLSDESC_CALLSEQ: {
1591     /// lower this to:
1592     ///    adrp  x0, :tlsdesc:var
1593     ///    ldr   x1, [x0, #:tlsdesc_lo12:var]
1594     ///    add   x0, x0, #:tlsdesc_lo12:var
1595     ///    .tlsdesccall var
1596     ///    blr   x1
1597     ///    (TPIDR_EL0 offset now in x0)
1598     const MachineOperand &MO_Sym = MI->getOperand(0);
1599     MachineOperand MO_TLSDESC_LO12(MO_Sym), MO_TLSDESC(MO_Sym);
1600     MCOperand Sym, SymTLSDescLo12, SymTLSDesc;
1601     MO_TLSDESC_LO12.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGEOFF);
1602     MO_TLSDESC.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGE);
1603     MCInstLowering.lowerOperand(MO_Sym, Sym);
1604     MCInstLowering.lowerOperand(MO_TLSDESC_LO12, SymTLSDescLo12);
1605     MCInstLowering.lowerOperand(MO_TLSDESC, SymTLSDesc);
1606 
1607     MCInst Adrp;
1608     Adrp.setOpcode(AArch64::ADRP);
1609     Adrp.addOperand(MCOperand::createReg(AArch64::X0));
1610     Adrp.addOperand(SymTLSDesc);
1611     EmitToStreamer(*OutStreamer, Adrp);
1612 
1613     MCInst Ldr;
1614     if (STI->isTargetILP32()) {
1615       Ldr.setOpcode(AArch64::LDRWui);
1616       Ldr.addOperand(MCOperand::createReg(AArch64::W1));
1617     } else {
1618       Ldr.setOpcode(AArch64::LDRXui);
1619       Ldr.addOperand(MCOperand::createReg(AArch64::X1));
1620     }
1621     Ldr.addOperand(MCOperand::createReg(AArch64::X0));
1622     Ldr.addOperand(SymTLSDescLo12);
1623     Ldr.addOperand(MCOperand::createImm(0));
1624     EmitToStreamer(*OutStreamer, Ldr);
1625 
1626     MCInst Add;
1627     if (STI->isTargetILP32()) {
1628       Add.setOpcode(AArch64::ADDWri);
1629       Add.addOperand(MCOperand::createReg(AArch64::W0));
1630       Add.addOperand(MCOperand::createReg(AArch64::W0));
1631     } else {
1632       Add.setOpcode(AArch64::ADDXri);
1633       Add.addOperand(MCOperand::createReg(AArch64::X0));
1634       Add.addOperand(MCOperand::createReg(AArch64::X0));
1635     }
1636     Add.addOperand(SymTLSDescLo12);
1637     Add.addOperand(MCOperand::createImm(AArch64_AM::getShiftValue(0)));
1638     EmitToStreamer(*OutStreamer, Add);
1639 
1640     // Emit a relocation-annotation. This expands to no code, but requests
1641     // the following instruction gets an R_AARCH64_TLSDESC_CALL.
1642     MCInst TLSDescCall;
1643     TLSDescCall.setOpcode(AArch64::TLSDESCCALL);
1644     TLSDescCall.addOperand(Sym);
1645     EmitToStreamer(*OutStreamer, TLSDescCall);
1646 
1647     MCInst Blr;
1648     Blr.setOpcode(AArch64::BLR);
1649     Blr.addOperand(MCOperand::createReg(AArch64::X1));
1650     EmitToStreamer(*OutStreamer, Blr);
1651 
1652     return;
1653   }
1654 
1655   case AArch64::JumpTableDest32:
1656   case AArch64::JumpTableDest16:
1657   case AArch64::JumpTableDest8:
1658     LowerJumpTableDest(*OutStreamer, *MI);
1659     return;
1660 
1661   case AArch64::FMOVH0:
1662   case AArch64::FMOVS0:
1663   case AArch64::FMOVD0:
1664     emitFMov0(*MI);
1665     return;
1666 
1667   case AArch64::MOPSMemoryCopyPseudo:
1668   case AArch64::MOPSMemoryMovePseudo:
1669   case AArch64::MOPSMemorySetPseudo:
1670   case AArch64::MOPSMemorySetTaggingPseudo:
1671     LowerMOPS(*OutStreamer, *MI);
1672     return;
1673 
1674   case TargetOpcode::STACKMAP:
1675     return LowerSTACKMAP(*OutStreamer, SM, *MI);
1676 
1677   case TargetOpcode::PATCHPOINT:
1678     return LowerPATCHPOINT(*OutStreamer, SM, *MI);
1679 
1680   case TargetOpcode::STATEPOINT:
1681     return LowerSTATEPOINT(*OutStreamer, SM, *MI);
1682 
1683   case TargetOpcode::FAULTING_OP:
1684     return LowerFAULTING_OP(*MI);
1685 
1686   case TargetOpcode::PATCHABLE_FUNCTION_ENTER:
1687     LowerPATCHABLE_FUNCTION_ENTER(*MI);
1688     return;
1689 
1690   case TargetOpcode::PATCHABLE_FUNCTION_EXIT:
1691     LowerPATCHABLE_FUNCTION_EXIT(*MI);
1692     return;
1693 
1694   case TargetOpcode::PATCHABLE_TAIL_CALL:
1695     LowerPATCHABLE_TAIL_CALL(*MI);
1696     return;
1697   case TargetOpcode::PATCHABLE_EVENT_CALL:
1698     return LowerPATCHABLE_EVENT_CALL(*MI, false);
1699   case TargetOpcode::PATCHABLE_TYPED_EVENT_CALL:
1700     return LowerPATCHABLE_EVENT_CALL(*MI, true);
1701 
1702   case AArch64::KCFI_CHECK:
1703     LowerKCFI_CHECK(*MI);
1704     return;
1705 
1706   case AArch64::HWASAN_CHECK_MEMACCESS:
1707   case AArch64::HWASAN_CHECK_MEMACCESS_SHORTGRANULES:
1708     LowerHWASAN_CHECK_MEMACCESS(*MI);
1709     return;
1710 
1711   case AArch64::SEH_StackAlloc:
1712     TS->emitARM64WinCFIAllocStack(MI->getOperand(0).getImm());
1713     return;
1714 
1715   case AArch64::SEH_SaveFPLR:
1716     TS->emitARM64WinCFISaveFPLR(MI->getOperand(0).getImm());
1717     return;
1718 
1719   case AArch64::SEH_SaveFPLR_X:
1720     assert(MI->getOperand(0).getImm() < 0 &&
1721            "Pre increment SEH opcode must have a negative offset");
1722     TS->emitARM64WinCFISaveFPLRX(-MI->getOperand(0).getImm());
1723     return;
1724 
1725   case AArch64::SEH_SaveReg:
1726     TS->emitARM64WinCFISaveReg(MI->getOperand(0).getImm(),
1727                                MI->getOperand(1).getImm());
1728     return;
1729 
1730   case AArch64::SEH_SaveReg_X:
1731     assert(MI->getOperand(1).getImm() < 0 &&
1732            "Pre increment SEH opcode must have a negative offset");
1733     TS->emitARM64WinCFISaveRegX(MI->getOperand(0).getImm(),
1734                                 -MI->getOperand(1).getImm());
1735     return;
1736 
1737   case AArch64::SEH_SaveRegP:
1738     if (MI->getOperand(1).getImm() == 30 && MI->getOperand(0).getImm() >= 19 &&
1739         MI->getOperand(0).getImm() <= 28) {
1740       assert((MI->getOperand(0).getImm() - 19) % 2 == 0 &&
1741              "Register paired with LR must be odd");
1742       TS->emitARM64WinCFISaveLRPair(MI->getOperand(0).getImm(),
1743                                     MI->getOperand(2).getImm());
1744       return;
1745     }
1746     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1747             "Non-consecutive registers not allowed for save_regp");
1748     TS->emitARM64WinCFISaveRegP(MI->getOperand(0).getImm(),
1749                                 MI->getOperand(2).getImm());
1750     return;
1751 
1752   case AArch64::SEH_SaveRegP_X:
1753     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1754             "Non-consecutive registers not allowed for save_regp_x");
1755     assert(MI->getOperand(2).getImm() < 0 &&
1756            "Pre increment SEH opcode must have a negative offset");
1757     TS->emitARM64WinCFISaveRegPX(MI->getOperand(0).getImm(),
1758                                  -MI->getOperand(2).getImm());
1759     return;
1760 
1761   case AArch64::SEH_SaveFReg:
1762     TS->emitARM64WinCFISaveFReg(MI->getOperand(0).getImm(),
1763                                 MI->getOperand(1).getImm());
1764     return;
1765 
1766   case AArch64::SEH_SaveFReg_X:
1767     assert(MI->getOperand(1).getImm() < 0 &&
1768            "Pre increment SEH opcode must have a negative offset");
1769     TS->emitARM64WinCFISaveFRegX(MI->getOperand(0).getImm(),
1770                                  -MI->getOperand(1).getImm());
1771     return;
1772 
1773   case AArch64::SEH_SaveFRegP:
1774     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1775             "Non-consecutive registers not allowed for save_regp");
1776     TS->emitARM64WinCFISaveFRegP(MI->getOperand(0).getImm(),
1777                                  MI->getOperand(2).getImm());
1778     return;
1779 
1780   case AArch64::SEH_SaveFRegP_X:
1781     assert((MI->getOperand(1).getImm() - MI->getOperand(0).getImm() == 1) &&
1782             "Non-consecutive registers not allowed for save_regp_x");
1783     assert(MI->getOperand(2).getImm() < 0 &&
1784            "Pre increment SEH opcode must have a negative offset");
1785     TS->emitARM64WinCFISaveFRegPX(MI->getOperand(0).getImm(),
1786                                   -MI->getOperand(2).getImm());
1787     return;
1788 
1789   case AArch64::SEH_SetFP:
1790     TS->emitARM64WinCFISetFP();
1791     return;
1792 
1793   case AArch64::SEH_AddFP:
1794     TS->emitARM64WinCFIAddFP(MI->getOperand(0).getImm());
1795     return;
1796 
1797   case AArch64::SEH_Nop:
1798     TS->emitARM64WinCFINop();
1799     return;
1800 
1801   case AArch64::SEH_PrologEnd:
1802     TS->emitARM64WinCFIPrologEnd();
1803     return;
1804 
1805   case AArch64::SEH_EpilogStart:
1806     TS->emitARM64WinCFIEpilogStart();
1807     return;
1808 
1809   case AArch64::SEH_EpilogEnd:
1810     TS->emitARM64WinCFIEpilogEnd();
1811     return;
1812 
1813   case AArch64::SEH_PACSignLR:
1814     TS->emitARM64WinCFIPACSignLR();
1815     return;
1816   }
1817 
1818   // Finally, do the automated lowerings for everything else.
1819   MCInst TmpInst;
1820   MCInstLowering.Lower(MI, TmpInst);
1821   EmitToStreamer(*OutStreamer, TmpInst);
1822 }
1823 
1824 void AArch64AsmPrinter::emitMachOIFuncStubBody(Module &M, const GlobalIFunc &GI,
1825                                                MCSymbol *LazyPointer) {
1826   // _ifunc:
1827   //   adrp    x16, lazy_pointer@GOTPAGE
1828   //   ldr     x16, [x16, lazy_pointer@GOTPAGEOFF]
1829   //   ldr     x16, [x16]
1830   //   br      x16
1831 
1832   {
1833     MCInst Adrp;
1834     Adrp.setOpcode(AArch64::ADRP);
1835     Adrp.addOperand(MCOperand::createReg(AArch64::X16));
1836     MCOperand SymPage;
1837     MCInstLowering.lowerOperand(
1838         MachineOperand::CreateMCSymbol(LazyPointer,
1839                                        AArch64II::MO_GOT | AArch64II::MO_PAGE),
1840         SymPage);
1841     Adrp.addOperand(SymPage);
1842     OutStreamer->emitInstruction(Adrp, *STI);
1843   }
1844 
1845   {
1846     MCInst Ldr;
1847     Ldr.setOpcode(AArch64::LDRXui);
1848     Ldr.addOperand(MCOperand::createReg(AArch64::X16));
1849     Ldr.addOperand(MCOperand::createReg(AArch64::X16));
1850     MCOperand SymPageOff;
1851     MCInstLowering.lowerOperand(
1852         MachineOperand::CreateMCSymbol(LazyPointer, AArch64II::MO_GOT |
1853                                                         AArch64II::MO_PAGEOFF),
1854         SymPageOff);
1855     Ldr.addOperand(SymPageOff);
1856     Ldr.addOperand(MCOperand::createImm(0));
1857     OutStreamer->emitInstruction(Ldr, *STI);
1858   }
1859 
1860   OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDRXui)
1861                                    .addReg(AArch64::X16)
1862                                    .addReg(AArch64::X16)
1863                                    .addImm(0),
1864                                *STI);
1865 
1866   OutStreamer->emitInstruction(MCInstBuilder(TM.getTargetTriple().isArm64e()
1867                                                  ? AArch64::BRAAZ
1868                                                  : AArch64::BR)
1869                                    .addReg(AArch64::X16),
1870                                *STI);
1871 }
1872 
1873 void AArch64AsmPrinter::emitMachOIFuncStubHelperBody(Module &M,
1874                                                      const GlobalIFunc &GI,
1875                                                      MCSymbol *LazyPointer) {
1876   // These stub helpers are only ever called once, so here we're optimizing for
1877   // minimum size by using the pre-indexed store variants, which saves a few
1878   // bytes of instructions to bump & restore sp.
1879 
1880   // _ifunc.stub_helper:
1881   //   stp	fp, lr, [sp, #-16]!
1882   //   mov	fp, sp
1883   //   stp	x1, x0, [sp, #-16]!
1884   //   stp	x3, x2, [sp, #-16]!
1885   //   stp	x5, x4, [sp, #-16]!
1886   //   stp	x7, x6, [sp, #-16]!
1887   //   stp	d1, d0, [sp, #-16]!
1888   //   stp	d3, d2, [sp, #-16]!
1889   //   stp	d5, d4, [sp, #-16]!
1890   //   stp	d7, d6, [sp, #-16]!
1891   //   bl	_resolver
1892   //   adrp	x16, lazy_pointer@GOTPAGE
1893   //   ldr	x16, [x16, lazy_pointer@GOTPAGEOFF]
1894   //   str	x0, [x16]
1895   //   mov	x16, x0
1896   //   ldp	d7, d6, [sp], #16
1897   //   ldp	d5, d4, [sp], #16
1898   //   ldp	d3, d2, [sp], #16
1899   //   ldp	d1, d0, [sp], #16
1900   //   ldp	x7, x6, [sp], #16
1901   //   ldp	x5, x4, [sp], #16
1902   //   ldp	x3, x2, [sp], #16
1903   //   ldp	x1, x0, [sp], #16
1904   //   ldp	fp, lr, [sp], #16
1905   //   br	x16
1906 
1907   OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXpre)
1908                                    .addReg(AArch64::SP)
1909                                    .addReg(AArch64::FP)
1910                                    .addReg(AArch64::LR)
1911                                    .addReg(AArch64::SP)
1912                                    .addImm(-2),
1913                                *STI);
1914 
1915   OutStreamer->emitInstruction(MCInstBuilder(AArch64::ADDXri)
1916                                    .addReg(AArch64::FP)
1917                                    .addReg(AArch64::SP)
1918                                    .addImm(0)
1919                                    .addImm(0),
1920                                *STI);
1921 
1922   for (int I = 0; I != 4; ++I)
1923     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPXpre)
1924                                      .addReg(AArch64::SP)
1925                                      .addReg(AArch64::X1 + 2 * I)
1926                                      .addReg(AArch64::X0 + 2 * I)
1927                                      .addReg(AArch64::SP)
1928                                      .addImm(-2),
1929                                  *STI);
1930 
1931   for (int I = 0; I != 4; ++I)
1932     OutStreamer->emitInstruction(MCInstBuilder(AArch64::STPDpre)
1933                                      .addReg(AArch64::SP)
1934                                      .addReg(AArch64::D1 + 2 * I)
1935                                      .addReg(AArch64::D0 + 2 * I)
1936                                      .addReg(AArch64::SP)
1937                                      .addImm(-2),
1938                                  *STI);
1939 
1940   OutStreamer->emitInstruction(
1941       MCInstBuilder(AArch64::BL)
1942           .addOperand(MCOperand::createExpr(lowerConstant(GI.getResolver()))),
1943       *STI);
1944 
1945   {
1946     MCInst Adrp;
1947     Adrp.setOpcode(AArch64::ADRP);
1948     Adrp.addOperand(MCOperand::createReg(AArch64::X16));
1949     MCOperand SymPage;
1950     MCInstLowering.lowerOperand(
1951         MachineOperand::CreateES(LazyPointer->getName().data() + 1,
1952                                  AArch64II::MO_GOT | AArch64II::MO_PAGE),
1953         SymPage);
1954     Adrp.addOperand(SymPage);
1955     OutStreamer->emitInstruction(Adrp, *STI);
1956   }
1957 
1958   {
1959     MCInst Ldr;
1960     Ldr.setOpcode(AArch64::LDRXui);
1961     Ldr.addOperand(MCOperand::createReg(AArch64::X16));
1962     Ldr.addOperand(MCOperand::createReg(AArch64::X16));
1963     MCOperand SymPageOff;
1964     MCInstLowering.lowerOperand(
1965         MachineOperand::CreateES(LazyPointer->getName().data() + 1,
1966                                  AArch64II::MO_GOT | AArch64II::MO_PAGEOFF),
1967         SymPageOff);
1968     Ldr.addOperand(SymPageOff);
1969     Ldr.addOperand(MCOperand::createImm(0));
1970     OutStreamer->emitInstruction(Ldr, *STI);
1971   }
1972 
1973   OutStreamer->emitInstruction(MCInstBuilder(AArch64::STRXui)
1974                                    .addReg(AArch64::X0)
1975                                    .addReg(AArch64::X16)
1976                                    .addImm(0),
1977                                *STI);
1978 
1979   OutStreamer->emitInstruction(MCInstBuilder(AArch64::ADDXri)
1980                                    .addReg(AArch64::X16)
1981                                    .addReg(AArch64::X0)
1982                                    .addImm(0)
1983                                    .addImm(0),
1984                                *STI);
1985 
1986   for (int I = 3; I != -1; --I)
1987     OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDPDpost)
1988                                      .addReg(AArch64::SP)
1989                                      .addReg(AArch64::D1 + 2 * I)
1990                                      .addReg(AArch64::D0 + 2 * I)
1991                                      .addReg(AArch64::SP)
1992                                      .addImm(2),
1993                                  *STI);
1994 
1995   for (int I = 3; I != -1; --I)
1996     OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDPXpost)
1997                                      .addReg(AArch64::SP)
1998                                      .addReg(AArch64::X1 + 2 * I)
1999                                      .addReg(AArch64::X0 + 2 * I)
2000                                      .addReg(AArch64::SP)
2001                                      .addImm(2),
2002                                  *STI);
2003 
2004   OutStreamer->emitInstruction(MCInstBuilder(AArch64::LDPXpost)
2005                                    .addReg(AArch64::SP)
2006                                    .addReg(AArch64::FP)
2007                                    .addReg(AArch64::LR)
2008                                    .addReg(AArch64::SP)
2009                                    .addImm(2),
2010                                *STI);
2011 
2012   OutStreamer->emitInstruction(MCInstBuilder(TM.getTargetTriple().isArm64e()
2013                                                  ? AArch64::BRAAZ
2014                                                  : AArch64::BR)
2015                                    .addReg(AArch64::X16),
2016                                *STI);
2017 }
2018 
2019 // Force static initialization.
2020 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64AsmPrinter() {
2021   RegisterAsmPrinter<AArch64AsmPrinter> X(getTheAArch64leTarget());
2022   RegisterAsmPrinter<AArch64AsmPrinter> Y(getTheAArch64beTarget());
2023   RegisterAsmPrinter<AArch64AsmPrinter> Z(getTheARM64Target());
2024   RegisterAsmPrinter<AArch64AsmPrinter> W(getTheARM64_32Target());
2025   RegisterAsmPrinter<AArch64AsmPrinter> V(getTheAArch64_32Target());
2026 }
2027