LLVM 19.0.0git
AArch64MCInstLower.cpp
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1//==-- AArch64MCInstLower.cpp - Convert AArch64 MachineInstr to an MCInst --==//
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 code to lower AArch64 MachineInstrs to their corresponding
10// MCInst records.
11//
12//===----------------------------------------------------------------------===//
13
14#include "AArch64MCInstLower.h"
21#include "llvm/IR/Mangler.h"
22#include "llvm/MC/MCContext.h"
23#include "llvm/MC/MCExpr.h"
24#include "llvm/MC/MCInst.h"
25#include "llvm/MC/MCStreamer.h"
26#include "llvm/Object/COFF.h"
31using namespace llvm;
32using namespace llvm::object;
33
35
37 : Ctx(ctx), Printer(printer) {}
38
42}
43
45 unsigned TargetFlags) const {
46 const Triple &TheTriple = Printer.TM.getTargetTriple();
47 if (!TheTriple.isOSBinFormatCOFF())
48 return Printer.getSymbolPreferLocal(*GV);
49
50 assert(TheTriple.isOSWindows() &&
51 "Windows is the only supported COFF target");
52
53 bool IsIndirect =
55 if (!IsIndirect) {
56 // For ARM64EC, symbol lookup in the MSVC linker has limited awareness
57 // of ARM64EC mangling ("#"/"$$h"). So object files need to refer to both
58 // the mangled and unmangled names of ARM64EC symbols, even if they aren't
59 // actually used by any relocations. Emit the necessary references here.
60 if (!TheTriple.isWindowsArm64EC() || !isa<Function>(GV) ||
61 !GV->hasExternalLinkage())
62 return Printer.getSymbol(GV);
63
64 StringRef Name = Printer.getSymbol(GV)->getName();
65 // Don't mangle ARM64EC runtime functions.
66 static constexpr StringLiteral ExcludedFns[] = {
67 "__os_arm64x_check_icall_cfg", "__os_arm64x_dispatch_call_no_redirect",
68 "__os_arm64x_check_icall"};
69 if (is_contained(ExcludedFns, Name))
70 return Printer.getSymbol(GV);
71
72 if (std::optional<std::string> MangledName =
74 MCSymbol *MangledSym = Ctx.getOrCreateSymbol(MangledName.value());
75 if (!cast<Function>(GV)->hasMetadata("arm64ec_hasguestexit")) {
76 Printer.OutStreamer->emitSymbolAttribute(Printer.getSymbol(GV),
78 Printer.OutStreamer->emitAssignment(
79 Printer.getSymbol(GV),
81 Ctx));
82 Printer.OutStreamer->emitSymbolAttribute(MangledSym, MCSA_WeakAntiDep);
83 Printer.OutStreamer->emitAssignment(
84 MangledSym,
87 }
88
89 if (TargetFlags & AArch64II::MO_ARM64EC_CALLMANGLE)
90 return MangledSym;
91 }
92
93 return Printer.getSymbol(GV);
94 }
95
97
98 if ((TargetFlags & AArch64II::MO_DLLIMPORT) &&
99 TheTriple.isWindowsArm64EC() &&
100 !(TargetFlags & AArch64II::MO_ARM64EC_CALLMANGLE) &&
101 isa<Function>(GV)) {
102 // __imp_aux is specific to arm64EC; it represents the actual address of
103 // an imported function without any thunks.
104 //
105 // If we see a reference to an "aux" symbol, also emit a reference to the
106 // corresponding non-aux symbol. Otherwise, the Microsoft linker behaves
107 // strangely when linking against x64 import libararies.
108 //
109 // emitSymbolAttribute() doesn't have any real effect here; it just
110 // ensures the symbol name appears in the assembly without any
111 // side-effects. It might make sense to design a cleaner way to express
112 // this.
113 Name = "__imp_";
114 Printer.TM.getNameWithPrefix(Name, GV,
115 Printer.getObjFileLowering().getMangler());
116 MCSymbol *ExtraSym = Ctx.getOrCreateSymbol(Name);
117 Printer.OutStreamer->emitSymbolAttribute(ExtraSym, MCSA_Global);
118
119 Name = "__imp_aux_";
120 } else if (TargetFlags & AArch64II::MO_DLLIMPORT) {
121 Name = "__imp_";
122 } else if (TargetFlags & AArch64II::MO_COFFSTUB) {
123 Name = ".refptr.";
124 }
125 Printer.TM.getNameWithPrefix(Name, GV,
126 Printer.getObjFileLowering().getMangler());
127
128 MCSymbol *MCSym = Ctx.getOrCreateSymbol(Name);
129
130 if (TargetFlags & AArch64II::MO_COFFSTUB) {
131 MachineModuleInfoCOFF &MMICOFF =
134 MMICOFF.getGVStubEntry(MCSym);
135
136 if (!StubSym.getPointer())
137 StubSym = MachineModuleInfoImpl::StubValueTy(Printer.getSymbol(GV), true);
138 }
139
140 return MCSym;
141}
142
143MCSymbol *
145 return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
146}
147
149 MCSymbol *Sym) const {
150 // FIXME: We would like an efficient form for this, so we don't have to do a
151 // lot of extra uniquing.
153 if ((MO.getTargetFlags() & AArch64II::MO_GOT) != 0) {
156 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
159 else
160 llvm_unreachable("Unexpected target flags with MO_GOT on GV operand");
161 } else if ((MO.getTargetFlags() & AArch64II::MO_TLS) != 0) {
164 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
167 else
168 llvm_unreachable("Unexpected target flags with MO_TLS on GV operand");
169 } else {
171 RefKind = MCSymbolRefExpr::VK_PAGE;
172 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
175 }
176 const MCExpr *Expr = MCSymbolRefExpr::create(Sym, RefKind, Ctx);
177 if (!MO.isJTI() && MO.getOffset())
179 Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
180 return MCOperand::createExpr(Expr);
181}
182
184 MCSymbol *Sym) const {
185 uint32_t RefFlags = 0;
186
188 RefFlags |= AArch64MCExpr::VK_GOT;
189 else if (MO.getTargetFlags() & AArch64II::MO_TLS) {
190 TLSModel::Model Model;
191 if (MO.isGlobal()) {
192 const GlobalValue *GV = MO.getGlobal();
193 Model = Printer.TM.getTLSModel(GV);
195 Model == TLSModel::LocalDynamic)
197
198 } else {
199 assert(MO.isSymbol() &&
200 StringRef(MO.getSymbolName()) == "_TLS_MODULE_BASE_" &&
201 "unexpected external TLS symbol");
202 // The general dynamic access sequence is used to get the
203 // address of _TLS_MODULE_BASE_.
205 }
206 switch (Model) {
208 RefFlags |= AArch64MCExpr::VK_GOTTPREL;
209 break;
211 RefFlags |= AArch64MCExpr::VK_TPREL;
212 break;
214 RefFlags |= AArch64MCExpr::VK_DTPREL;
215 break;
217 RefFlags |= AArch64MCExpr::VK_TLSDESC;
218 break;
219 }
220 } else if (MO.getTargetFlags() & AArch64II::MO_PREL) {
221 RefFlags |= AArch64MCExpr::VK_PREL;
222 } else {
223 // No modifier means this is a generic reference, classified as absolute for
224 // the cases where it matters (:abs_g0: etc).
225 RefFlags |= AArch64MCExpr::VK_ABS;
226 }
227
229 RefFlags |= AArch64MCExpr::VK_PAGE;
230 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
232 RefFlags |= AArch64MCExpr::VK_PAGEOFF;
234 RefFlags |= AArch64MCExpr::VK_G3;
236 RefFlags |= AArch64MCExpr::VK_G2;
238 RefFlags |= AArch64MCExpr::VK_G1;
240 RefFlags |= AArch64MCExpr::VK_G0;
242 RefFlags |= AArch64MCExpr::VK_HI12;
243
245 RefFlags |= AArch64MCExpr::VK_NC;
246
247 const MCExpr *Expr =
249 if (!MO.isJTI() && MO.getOffset())
251 Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
252
254 RefKind = static_cast<AArch64MCExpr::VariantKind>(RefFlags);
255 Expr = AArch64MCExpr::create(Expr, RefKind, Ctx);
256
257 return MCOperand::createExpr(Expr);
258}
259
261 MCSymbol *Sym) const {
262 uint32_t RefFlags = 0;
263
267 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
270
271 } else if (MO.getTargetFlags() & AArch64II::MO_S) {
272 RefFlags |= AArch64MCExpr::VK_SABS;
273 } else {
274 RefFlags |= AArch64MCExpr::VK_ABS;
275
277 RefFlags |= AArch64MCExpr::VK_PAGE;
278 else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
281 }
282
284 RefFlags |= AArch64MCExpr::VK_G3;
286 RefFlags |= AArch64MCExpr::VK_G2;
288 RefFlags |= AArch64MCExpr::VK_G1;
290 RefFlags |= AArch64MCExpr::VK_G0;
291
292 // FIXME: Currently we only set VK_NC for MO_G3/MO_G2/MO_G1/MO_G0. This is
293 // because setting VK_NC for others would mean setting their respective
294 // RefFlags correctly. We should do this in a separate patch.
295 if (MO.getTargetFlags() & AArch64II::MO_NC) {
296 auto MOFrag = (MO.getTargetFlags() & AArch64II::MO_FRAGMENT);
297 if (MOFrag == AArch64II::MO_G3 || MOFrag == AArch64II::MO_G2 ||
298 MOFrag == AArch64II::MO_G1 || MOFrag == AArch64II::MO_G0)
299 RefFlags |= AArch64MCExpr::VK_NC;
300 }
301
302 const MCExpr *Expr =
304 if (!MO.isJTI() && MO.getOffset())
306 Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
307
308 auto RefKind = static_cast<AArch64MCExpr::VariantKind>(RefFlags);
310 "Invalid relocation requested");
311 Expr = AArch64MCExpr::create(Expr, RefKind, Ctx);
312
313 return MCOperand::createExpr(Expr);
314}
315
317 MCSymbol *Sym) const {
318 if (Printer.TM.getTargetTriple().isOSBinFormatMachO())
319 return lowerSymbolOperandMachO(MO, Sym);
320 if (Printer.TM.getTargetTriple().isOSBinFormatCOFF())
321 return lowerSymbolOperandCOFF(MO, Sym);
322
323 assert(Printer.TM.getTargetTriple().isOSBinFormatELF() && "Invalid target");
324 return lowerSymbolOperandELF(MO, Sym);
325}
326
328 MCOperand &MCOp) const {
329 switch (MO.getType()) {
330 default:
331 llvm_unreachable("unknown operand type");
333 // Ignore all implicit register operands.
334 if (MO.isImplicit())
335 return false;
336 MCOp = MCOperand::createReg(MO.getReg());
337 break;
339 // Regmasks are like implicit defs.
340 return false;
342 MCOp = MCOperand::createImm(MO.getImm());
343 break;
347 break;
350 break;
353 break;
355 MCOp = LowerSymbolOperand(MO, MO.getMCSymbol());
356 break;
358 MCOp = LowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()));
359 break;
361 MCOp = LowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()));
362 break;
364 MCOp = LowerSymbolOperand(
365 MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()));
366 break;
367 }
368 return true;
369}
370
372 OutMI.setOpcode(MI->getOpcode());
373
374 for (const MachineOperand &MO : MI->operands()) {
375 MCOperand MCOp;
376 if (lowerOperand(MO, MCOp))
377 OutMI.addOperand(MCOp);
378 }
379
380 switch (OutMI.getOpcode()) {
381 case AArch64::CATCHRET:
382 OutMI = MCInst();
383 OutMI.setOpcode(AArch64::RET);
384 OutMI.addOperand(MCOperand::createReg(AArch64::LR));
385 break;
386 case AArch64::CLEANUPRET:
387 OutMI = MCInst();
388 OutMI.setOpcode(AArch64::RET);
389 OutMI.addOperand(MCOperand::createReg(AArch64::LR));
390 break;
391 }
392}
cl::opt< bool > EnableAArch64ELFLocalDynamicTLSGeneration("aarch64-elf-ldtls-generation", cl::Hidden, cl::desc("Allow AArch64 Local Dynamic TLS code generation"), cl::init(false))
cl::opt< bool > EnableAArch64ELFLocalDynamicTLSGeneration
dxil pretty printer
dxil pretty DXIL Metadata Pretty Printer
std::string Name
Symbol * Sym
Definition: ELF_riscv.cpp:479
IRTranslator LLVM IR MI
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static const AArch64MCExpr * create(const MCExpr *Expr, VariantKind Kind, MCContext &Ctx)
MCSymbol * GetExternalSymbolSymbol(const MachineOperand &MO) const
MCOperand lowerSymbolOperandCOFF(const MachineOperand &MO, MCSymbol *Sym) const
MCOperand LowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym) const
MCSymbol * GetGlobalValueSymbol(const GlobalValue *GV, unsigned TargetFlags) const
MCOperand lowerSymbolOperandELF(const MachineOperand &MO, MCSymbol *Sym) const
AArch64MCInstLower(MCContext &ctx, AsmPrinter &printer)
void Lower(const MachineInstr *MI, MCInst &OutMI) const
bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp) const
MCSymbol * GetGlobalAddressSymbol(const MachineOperand &MO) const
MCOperand lowerSymbolOperandMachO(const MachineOperand &MO, MCSymbol *Sym) const
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:84
const TargetLoweringObjectFile & getObjFileLowering() const
Return information about object file lowering.
Definition: AsmPrinter.cpp:398
MCSymbol * getSymbol(const GlobalValue *GV) const
Definition: AsmPrinter.cpp:698
TargetMachine & TM
Target machine description.
Definition: AsmPrinter.h:87
virtual MCSymbol * GetCPISymbol(unsigned CPID) const
Return the symbol for the specified constant pool entry.
MCSymbol * GetJTISymbol(unsigned JTID, bool isLinkerPrivate=false) const
Return the symbol for the specified jump table entry.
MCSymbol * getSymbolPreferLocal(const GlobalValue &GV) const
Similar to getSymbol() but preferred for references.
Definition: AsmPrinter.cpp:702
MachineModuleInfo * MMI
This is a pointer to the current MachineModuleInfo.
Definition: AsmPrinter.h:105
MCSymbol * GetExternalSymbolSymbol(Twine Sym) const
Return the MCSymbol for the specified ExternalSymbol.
std::unique_ptr< MCStreamer > OutStreamer
This is the MCStreamer object for the file we are generating.
Definition: AsmPrinter.h:99
MCSymbol * GetBlockAddressSymbol(const BlockAddress *BA) const
Return the MCSymbol used to satisfy BlockAddress uses of the specified basic block.
bool hasExternalLinkage() const
Definition: GlobalValue.h:510
static const MCBinaryExpr * createAdd(const MCExpr *LHS, const MCExpr *RHS, MCContext &Ctx)
Definition: MCExpr.h:534
static const MCConstantExpr * create(int64_t Value, MCContext &Ctx, bool PrintInHex=false, unsigned SizeInBytes=0)
Definition: MCExpr.cpp:194
Context object for machine code objects.
Definition: MCContext.h:76
MCSymbol * getOrCreateSymbol(const Twine &Name)
Lookup the symbol inside with the specified Name.
Definition: MCContext.cpp:200
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
Instances of this class represent a single low-level machine instruction.
Definition: MCInst.h:184
unsigned getOpcode() const
Definition: MCInst.h:198
void addOperand(const MCOperand Op)
Definition: MCInst.h:210
void setOpcode(unsigned Op)
Definition: MCInst.h:197
Instances of this class represent operands of the MCInst class.
Definition: MCInst.h:36
static MCOperand createReg(unsigned Reg)
Definition: MCInst.h:134
static MCOperand createExpr(const MCExpr *Val)
Definition: MCInst.h:162
static MCOperand createImm(int64_t Val)
Definition: MCInst.h:141
static const MCSymbolRefExpr * create(const MCSymbol *Symbol, MCContext &Ctx)
Definition: MCExpr.h:395
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:40
StringRef getName() const
getName - Get the symbol name.
Definition: MCSymbol.h:205
MCSymbol * getSymbol() const
Return the MCSymbol for this basic block.
Representation of each machine instruction.
Definition: MachineInstr.h:68
MachineModuleInfoCOFF - This is a MachineModuleInfoImpl implementation for COFF targets.
StubValueTy & getGVStubEntry(MCSymbol *Sym)
Ty & getObjFileInfo()
Keep track of various per-module pieces of information for backends that would like to do so.
MachineOperand class - Representation of each machine instruction operand.
const GlobalValue * getGlobal() const
int64_t getImm() const
bool isImplicit() const
MachineBasicBlock * getMBB() const
bool isSymbol() const
isSymbol - Tests if this is a MO_ExternalSymbol operand.
bool isJTI() const
isJTI - Tests if this is a MO_JumpTableIndex operand.
const BlockAddress * getBlockAddress() const
unsigned getTargetFlags() const
bool isGlobal() const
isGlobal - Tests if this is a MO_GlobalAddress operand.
MachineOperandType getType() const
getType - Returns the MachineOperandType for this operand.
const char * getSymbolName() const
Register getReg() const
getReg - Returns the register number.
MCSymbol * getMCSymbol() const
@ MO_Immediate
Immediate operand.
@ MO_ConstantPoolIndex
Address of indexed Constant in Constant Pool.
@ MO_MCSymbol
MCSymbol reference (for debug/eh info)
@ MO_GlobalAddress
Address of a global value.
@ MO_RegisterMask
Mask of preserved registers.
@ MO_BlockAddress
Address of a basic block.
@ MO_MachineBasicBlock
MachineBasicBlock reference.
@ MO_Register
Register operand.
@ MO_ExternalSymbol
Name of external global symbol.
@ MO_JumpTableIndex
Address of indexed Jump Table for switch.
int64_t getOffset() const
Return the offset from the symbol in this operand.
PointerIntPair - This class implements a pair of a pointer and small integer.
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:26
A wrapper around a string literal that serves as a proxy for constructing global tables of StringRefs...
Definition: StringRef.h:849
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
TLSModel::Model getTLSModel(const GlobalValue *GV) const
Returns the TLS model which should be used for the given global variable.
const Triple & getTargetTriple() const
void getNameWithPrefix(SmallVectorImpl< char > &Name, const GlobalValue *GV, Mangler &Mang, bool MayAlwaysUsePrivate=false) const
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
bool isOSBinFormatMachO() const
Tests whether the environment is MachO.
Definition: Triple.h:716
bool isOSBinFormatCOFF() const
Tests whether the OS uses the COFF binary format.
Definition: Triple.h:708
bool isOSWindows() const
Tests whether the OS is Windows.
Definition: Triple.h:608
bool isWindowsArm64EC() const
Definition: Triple.h:624
bool isOSBinFormatELF() const
Tests whether the OS uses the ELF binary format.
Definition: Triple.h:703
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
@ MO_DLLIMPORT
MO_DLLIMPORT - On a symbol operand, this represents that the reference to the symbol is for an import...
@ MO_NC
MO_NC - Indicates whether the linker is expected to check the symbol reference for overflow.
@ MO_G1
MO_G1 - A symbol operand with this flag (granule 1) represents the bits 16-31 of a 64-bit address,...
@ MO_S
MO_S - Indicates that the bits of the symbol operand represented by MO_G0 etc are signed.
@ MO_PAGEOFF
MO_PAGEOFF - A symbol operand with this flag represents the offset of that symbol within a 4K page.
@ MO_GOT
MO_GOT - This flag indicates that a symbol operand represents the address of the GOT entry for the sy...
@ MO_PREL
MO_PREL - Indicates that the bits of the symbol operand represented by MO_G0 etc are PC relative.
@ MO_G0
MO_G0 - A symbol operand with this flag (granule 0) represents the bits 0-15 of a 64-bit address,...
@ MO_ARM64EC_CALLMANGLE
MO_ARM64EC_CALLMANGLE - Operand refers to the Arm64EC-mangled version of a symbol,...
@ MO_PAGE
MO_PAGE - A symbol operand with this flag represents the pc-relative offset of the 4K page containing...
@ MO_HI12
MO_HI12 - This flag indicates that a symbol operand represents the bits 13-24 of a 64-bit address,...
@ MO_TLS
MO_TLS - Indicates that the operand being accessed is some kind of thread-local symbol.
@ MO_G2
MO_G2 - A symbol operand with this flag (granule 2) represents the bits 32-47 of a 64-bit address,...
@ MO_G3
MO_G3 - A symbol operand with this flag (granule 3) represents the high 16-bits of a 64-bit address,...
@ MO_COFFSTUB
MO_COFFSTUB - On a symbol operand "FOO", this indicates that the reference is actually to the "....
@ GeneralDynamic
Definition: CodeGen.h:46
std::optional< std::string > getArm64ECMangledFunctionName(StringRef Name)
Definition: COFF.h:1366
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
bool is_contained(R &&Range, const E &Element)
Returns true if Element is found in Range.
Definition: STLExtras.h:1888
@ MCSA_Global
.type _foo, @gnu_unique_object
Definition: MCDirectives.h:30
@ MCSA_WeakAntiDep
.weak_anti_dep (COFF)
Definition: MCDirectives.h:49