| //===- llvm/CodeGen/AsmPrinter.h - AsmPrinter Framework ---------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains a class to be used as the base class for target specific |
| // asm writers. This class primarily handles common functionality used by |
| // all asm writers. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CODEGEN_ASMPRINTER_H |
| #define LLVM_CODEGEN_ASMPRINTER_H |
| |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/DenseSet.h" |
| #include "llvm/ADT/MapVector.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/BinaryFormat/Dwarf.h" |
| #include "llvm/CodeGen/AsmPrinterHandler.h" |
| #include "llvm/CodeGen/DwarfStringPoolEntry.h" |
| #include "llvm/CodeGen/MachineFunctionPass.h" |
| #include "llvm/CodeGen/StackMaps.h" |
| #include "llvm/IR/InlineAsm.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include <cstdint> |
| #include <memory> |
| #include <utility> |
| #include <vector> |
| |
| namespace llvm { |
| |
| class AddrLabelMap; |
| class BasicBlock; |
| class BlockAddress; |
| class Constant; |
| class ConstantArray; |
| class DataLayout; |
| class DIE; |
| class DIEAbbrev; |
| class DwarfDebug; |
| class GCMetadataPrinter; |
| class GCStrategy; |
| class GlobalAlias; |
| class GlobalObject; |
| class GlobalValue; |
| class GlobalVariable; |
| class MachineBasicBlock; |
| class MachineConstantPoolValue; |
| class MachineDominatorTree; |
| class MachineFunction; |
| class MachineInstr; |
| class MachineJumpTableInfo; |
| class MachineLoopInfo; |
| class MachineModuleInfo; |
| class MachineOptimizationRemarkEmitter; |
| class MCAsmInfo; |
| class MCCFIInstruction; |
| class MCContext; |
| class MCExpr; |
| class MCInst; |
| class MCSection; |
| class MCStreamer; |
| class MCSubtargetInfo; |
| class MCSymbol; |
| class MCTargetOptions; |
| class MDNode; |
| class Module; |
| class PseudoProbeHandler; |
| class raw_ostream; |
| class StringRef; |
| class TargetLoweringObjectFile; |
| class TargetMachine; |
| class Twine; |
| |
| namespace remarks { |
| class RemarkStreamer; |
| } |
| |
| /// This class is intended to be used as a driving class for all asm writers. |
| class AsmPrinter : public MachineFunctionPass { |
| public: |
| /// Target machine description. |
| TargetMachine &TM; |
| |
| /// Target Asm Printer information. |
| const MCAsmInfo *MAI = nullptr; |
| |
| /// This is the context for the output file that we are streaming. This owns |
| /// all of the global MC-related objects for the generated translation unit. |
| MCContext &OutContext; |
| |
| /// This is the MCStreamer object for the file we are generating. This |
| /// contains the transient state for the current translation unit that we are |
| /// generating (such as the current section etc). |
| std::unique_ptr<MCStreamer> OutStreamer; |
| |
| /// The current machine function. |
| MachineFunction *MF = nullptr; |
| |
| /// This is a pointer to the current MachineModuleInfo. |
| MachineModuleInfo *MMI = nullptr; |
| |
| /// This is a pointer to the current MachineDominatorTree. |
| MachineDominatorTree *MDT = nullptr; |
| |
| /// This is a pointer to the current MachineLoopInfo. |
| MachineLoopInfo *MLI = nullptr; |
| |
| /// Optimization remark emitter. |
| MachineOptimizationRemarkEmitter *ORE = nullptr; |
| |
| /// The symbol for the entry in __patchable_function_entires. |
| MCSymbol *CurrentPatchableFunctionEntrySym = nullptr; |
| |
| /// The symbol for the current function. This is recalculated at the beginning |
| /// of each call to runOnMachineFunction(). |
| MCSymbol *CurrentFnSym = nullptr; |
| |
| /// The symbol for the current function descriptor on AIX. This is created |
| /// at the beginning of each call to SetupMachineFunction(). |
| MCSymbol *CurrentFnDescSym = nullptr; |
| |
| /// The symbol used to represent the start of the current function for the |
| /// purpose of calculating its size (e.g. using the .size directive). By |
| /// default, this is equal to CurrentFnSym. |
| MCSymbol *CurrentFnSymForSize = nullptr; |
| |
| /// Map a basic block section ID to the begin and end symbols of that section |
| /// which determine the section's range. |
| struct MBBSectionRange { |
| MCSymbol *BeginLabel, *EndLabel; |
| }; |
| |
| MapVector<unsigned, MBBSectionRange> MBBSectionRanges; |
| |
| /// Map global GOT equivalent MCSymbols to GlobalVariables and keep track of |
| /// its number of uses by other globals. |
| using GOTEquivUsePair = std::pair<const GlobalVariable *, unsigned>; |
| MapVector<const MCSymbol *, GOTEquivUsePair> GlobalGOTEquivs; |
| |
| /// struct HandlerInfo and Handlers permit users or target extended |
| /// AsmPrinter to add their own handlers. |
| struct HandlerInfo { |
| std::unique_ptr<AsmPrinterHandler> Handler; |
| StringRef TimerName; |
| StringRef TimerDescription; |
| StringRef TimerGroupName; |
| StringRef TimerGroupDescription; |
| |
| HandlerInfo(std::unique_ptr<AsmPrinterHandler> Handler, StringRef TimerName, |
| StringRef TimerDescription, StringRef TimerGroupName, |
| StringRef TimerGroupDescription) |
| : Handler(std::move(Handler)), TimerName(TimerName), |
| TimerDescription(TimerDescription), TimerGroupName(TimerGroupName), |
| TimerGroupDescription(TimerGroupDescription) {} |
| }; |
| |
| // Flags representing which CFI section is required for a function/module. |
| enum class CFISection : unsigned { |
| None = 0, ///< Do not emit either .eh_frame or .debug_frame |
| EH = 1, ///< Emit .eh_frame |
| Debug = 2 ///< Emit .debug_frame |
| }; |
| |
| private: |
| MCSymbol *CurrentFnEnd = nullptr; |
| |
| /// Map a basic block section ID to the exception symbol associated with that |
| /// section. Map entries are assigned and looked up via |
| /// AsmPrinter::getMBBExceptionSym. |
| DenseMap<unsigned, MCSymbol *> MBBSectionExceptionSyms; |
| |
| // The symbol used to represent the start of the current BB section of the |
| // function. This is used to calculate the size of the BB section. |
| MCSymbol *CurrentSectionBeginSym = nullptr; |
| |
| /// This map keeps track of which symbol is being used for the specified basic |
| /// block's address of label. |
| std::unique_ptr<AddrLabelMap> AddrLabelSymbols; |
| |
| /// The garbage collection metadata printer table. |
| DenseMap<GCStrategy *, std::unique_ptr<GCMetadataPrinter>> GCMetadataPrinters; |
| |
| /// Emit comments in assembly output if this is true. |
| bool VerboseAsm; |
| |
| /// Output stream for the stack usage file (i.e., .su file). |
| std::unique_ptr<raw_fd_ostream> StackUsageStream; |
| |
| /// List of symbols to be inserted into PC sections. |
| DenseMap<const MDNode *, SmallVector<const MCSymbol *>> PCSectionsSymbols; |
| |
| static char ID; |
| |
| protected: |
| MCSymbol *CurrentFnBegin = nullptr; |
| |
| /// For dso_local functions, the current $local alias for the function. |
| MCSymbol *CurrentFnBeginLocal = nullptr; |
| |
| /// A vector of all debug/EH info emitters we should use. This vector |
| /// maintains ownership of the emitters. |
| std::vector<HandlerInfo> Handlers; |
| size_t NumUserHandlers = 0; |
| |
| StackMaps SM; |
| |
| private: |
| /// If generated on the fly this own the instance. |
| std::unique_ptr<MachineDominatorTree> OwnedMDT; |
| |
| /// If generated on the fly this own the instance. |
| std::unique_ptr<MachineLoopInfo> OwnedMLI; |
| |
| /// If the target supports dwarf debug info, this pointer is non-null. |
| DwarfDebug *DD = nullptr; |
| |
| /// A handler that supports pseudo probe emission with embedded inline |
| /// context. |
| PseudoProbeHandler *PP = nullptr; |
| |
| /// CFISection type the module needs i.e. either .eh_frame or .debug_frame. |
| CFISection ModuleCFISection = CFISection::None; |
| |
| /// True if the module contains split-stack functions. This is used to |
| /// emit .note.GNU-split-stack section as required by the linker for |
| /// special handling split-stack function calling no-split-stack function. |
| bool HasSplitStack = false; |
| |
| /// True if the module contains no-split-stack functions. This is used to emit |
| /// .note.GNU-no-split-stack section when it also contains functions without a |
| /// split stack prologue. |
| bool HasNoSplitStack = false; |
| |
| /// Raw FDOstream for outputting machine basic block frequncies if the |
| /// --mbb-profile-dump flag is set for downstream cost modelling applications |
| std::unique_ptr<raw_fd_ostream> MBBProfileDumpFileOutput; |
| |
| protected: |
| explicit AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer); |
| |
| public: |
| ~AsmPrinter() override; |
| |
| DwarfDebug *getDwarfDebug() { return DD; } |
| DwarfDebug *getDwarfDebug() const { return DD; } |
| |
| uint16_t getDwarfVersion() const; |
| void setDwarfVersion(uint16_t Version); |
| |
| bool isDwarf64() const; |
| |
| /// Returns 4 for DWARF32 and 8 for DWARF64. |
| unsigned int getDwarfOffsetByteSize() const; |
| |
| /// Returns 4 for DWARF32 and 12 for DWARF64. |
| unsigned int getUnitLengthFieldByteSize() const; |
| |
| /// Returns information about the byte size of DW_FORM values. |
| dwarf::FormParams getDwarfFormParams() const; |
| |
| bool isPositionIndependent() const; |
| |
| /// Return true if assembly output should contain comments. |
| bool isVerbose() const { return VerboseAsm; } |
| |
| /// Return a unique ID for the current function. |
| unsigned getFunctionNumber() const; |
| |
| /// Return symbol for the function pseudo stack if the stack frame is not a |
| /// register based. |
| virtual const MCSymbol *getFunctionFrameSymbol() const { return nullptr; } |
| |
| MCSymbol *getFunctionBegin() const { return CurrentFnBegin; } |
| MCSymbol *getFunctionEnd() const { return CurrentFnEnd; } |
| |
| // Return the exception symbol associated with the MBB section containing a |
| // given basic block. |
| MCSymbol *getMBBExceptionSym(const MachineBasicBlock &MBB); |
| |
| /// Return the symbol to be used for the specified basic block when its |
| /// address is taken. This cannot be its normal LBB label because the block |
| /// may be accessed outside its containing function. |
| MCSymbol *getAddrLabelSymbol(const BasicBlock *BB) { |
| return getAddrLabelSymbolToEmit(BB).front(); |
| } |
| |
| /// Return the symbol to be used for the specified basic block when its |
| /// address is taken. If other blocks were RAUW'd to this one, we may have |
| /// to emit them as well, return the whole set. |
| ArrayRef<MCSymbol *> getAddrLabelSymbolToEmit(const BasicBlock *BB); |
| |
| /// If the specified function has had any references to address-taken blocks |
| /// generated, but the block got deleted, return the symbol now so we can |
| /// emit it. This prevents emitting a reference to a symbol that has no |
| /// definition. |
| void takeDeletedSymbolsForFunction(const Function *F, |
| std::vector<MCSymbol *> &Result); |
| |
| /// Return information about object file lowering. |
| const TargetLoweringObjectFile &getObjFileLowering() const; |
| |
| /// Return information about data layout. |
| const DataLayout &getDataLayout() const; |
| |
| /// Return the pointer size from the TargetMachine |
| unsigned getPointerSize() const; |
| |
| /// Return information about subtarget. |
| const MCSubtargetInfo &getSubtargetInfo() const; |
| |
| void EmitToStreamer(MCStreamer &S, const MCInst &Inst); |
| |
| /// Emits inital debug location directive. |
| void emitInitialRawDwarfLocDirective(const MachineFunction &MF); |
| |
| /// Return the current section we are emitting to. |
| const MCSection *getCurrentSection() const; |
| |
| void getNameWithPrefix(SmallVectorImpl<char> &Name, |
| const GlobalValue *GV) const; |
| |
| MCSymbol *getSymbol(const GlobalValue *GV) const; |
| |
| /// Similar to getSymbol() but preferred for references. On ELF, this uses a |
| /// local symbol if a reference to GV is guaranteed to be resolved to the |
| /// definition in the same module. |
| MCSymbol *getSymbolPreferLocal(const GlobalValue &GV) const; |
| |
| bool doesDwarfUseRelocationsAcrossSections() const { |
| return DwarfUsesRelocationsAcrossSections; |
| } |
| |
| void setDwarfUsesRelocationsAcrossSections(bool Enable) { |
| DwarfUsesRelocationsAcrossSections = Enable; |
| } |
| |
| //===------------------------------------------------------------------===// |
| // XRay instrumentation implementation. |
| //===------------------------------------------------------------------===// |
| public: |
| // This describes the kind of sled we're storing in the XRay table. |
| enum class SledKind : uint8_t { |
| FUNCTION_ENTER = 0, |
| FUNCTION_EXIT = 1, |
| TAIL_CALL = 2, |
| LOG_ARGS_ENTER = 3, |
| CUSTOM_EVENT = 4, |
| TYPED_EVENT = 5, |
| }; |
| |
| // The table will contain these structs that point to the sled, the function |
| // containing the sled, and what kind of sled (and whether they should always |
| // be instrumented). We also use a version identifier that the runtime can use |
| // to decide what to do with the sled, depending on the version of the sled. |
| struct XRayFunctionEntry { |
| const MCSymbol *Sled; |
| const MCSymbol *Function; |
| SledKind Kind; |
| bool AlwaysInstrument; |
| const class Function *Fn; |
| uint8_t Version; |
| |
| void emit(int, MCStreamer *) const; |
| }; |
| |
| // All the sleds to be emitted. |
| SmallVector<XRayFunctionEntry, 4> Sleds; |
| |
| // Helper function to record a given XRay sled. |
| void recordSled(MCSymbol *Sled, const MachineInstr &MI, SledKind Kind, |
| uint8_t Version = 0); |
| |
| /// Emit a table with all XRay instrumentation points. |
| void emitXRayTable(); |
| |
| void emitPatchableFunctionEntries(); |
| |
| //===------------------------------------------------------------------===// |
| // MachineFunctionPass Implementation. |
| //===------------------------------------------------------------------===// |
| |
| /// Record analysis usage. |
| void getAnalysisUsage(AnalysisUsage &AU) const override; |
| |
| /// Set up the AsmPrinter when we are working on a new module. If your pass |
| /// overrides this, it must make sure to explicitly call this implementation. |
| bool doInitialization(Module &M) override; |
| |
| /// Shut down the asmprinter. If you override this in your pass, you must make |
| /// sure to call it explicitly. |
| bool doFinalization(Module &M) override; |
| |
| /// Emit the specified function out to the OutStreamer. |
| bool runOnMachineFunction(MachineFunction &MF) override { |
| SetupMachineFunction(MF); |
| emitFunctionBody(); |
| return false; |
| } |
| |
| //===------------------------------------------------------------------===// |
| // Coarse grained IR lowering routines. |
| //===------------------------------------------------------------------===// |
| |
| /// This should be called when a new MachineFunction is being processed from |
| /// runOnMachineFunction. |
| virtual void SetupMachineFunction(MachineFunction &MF); |
| |
| /// This method emits the body and trailer for a function. |
| void emitFunctionBody(); |
| |
| void emitCFIInstruction(const MachineInstr &MI); |
| |
| void emitFrameAlloc(const MachineInstr &MI); |
| |
| void emitStackSizeSection(const MachineFunction &MF); |
| |
| void emitStackUsage(const MachineFunction &MF); |
| |
| void emitBBAddrMapSection(const MachineFunction &MF); |
| |
| void emitKCFITrapEntry(const MachineFunction &MF, const MCSymbol *Symbol); |
| virtual void emitKCFITypeId(const MachineFunction &MF); |
| |
| void emitPseudoProbe(const MachineInstr &MI); |
| |
| void emitRemarksSection(remarks::RemarkStreamer &RS); |
| |
| /// Emits a label as reference for PC sections. |
| void emitPCSectionsLabel(const MachineFunction &MF, const MDNode &MD); |
| |
| /// Emits the PC sections collected from instructions. |
| void emitPCSections(const MachineFunction &MF); |
| |
| /// Get the CFISection type for a function. |
| CFISection getFunctionCFISectionType(const Function &F) const; |
| |
| /// Get the CFISection type for a function. |
| CFISection getFunctionCFISectionType(const MachineFunction &MF) const; |
| |
| /// Get the CFISection type for the module. |
| CFISection getModuleCFISectionType() const { return ModuleCFISection; } |
| |
| bool needsSEHMoves(); |
| |
| /// Since emitting CFI unwind information is entangled with supporting the |
| /// exceptions, this returns true for platforms which use CFI unwind |
| /// information for debugging purpose when |
| /// `MCAsmInfo::ExceptionsType == ExceptionHandling::None`. |
| bool needsCFIForDebug() const; |
| |
| /// Print to the current output stream assembly representations of the |
| /// constants in the constant pool MCP. This is used to print out constants |
| /// which have been "spilled to memory" by the code generator. |
| virtual void emitConstantPool(); |
| |
| /// Print assembly representations of the jump tables used by the current |
| /// function to the current output stream. |
| virtual void emitJumpTableInfo(); |
| |
| /// Emit the specified global variable to the .s file. |
| virtual void emitGlobalVariable(const GlobalVariable *GV); |
| |
| /// Check to see if the specified global is a special global used by LLVM. If |
| /// so, emit it and return true, otherwise do nothing and return false. |
| bool emitSpecialLLVMGlobal(const GlobalVariable *GV); |
| |
| /// `llvm.global_ctors` and `llvm.global_dtors` are arrays of Structor |
| /// structs. |
| /// |
| /// Priority - init priority |
| /// Func - global initialization or global clean-up function |
| /// ComdatKey - associated data |
| struct Structor { |
| int Priority = 0; |
| Constant *Func = nullptr; |
| GlobalValue *ComdatKey = nullptr; |
| |
| Structor() = default; |
| }; |
| |
| /// This method gathers an array of Structors and then sorts them out by |
| /// Priority. |
| /// @param List The initializer of `llvm.global_ctors` or `llvm.global_dtors` |
| /// array. |
| /// @param[out] Structors Sorted Structor structs by Priority. |
| void preprocessXXStructorList(const DataLayout &DL, const Constant *List, |
| SmallVector<Structor, 8> &Structors); |
| |
| /// This method emits `llvm.global_ctors` or `llvm.global_dtors` list. |
| virtual void emitXXStructorList(const DataLayout &DL, const Constant *List, |
| bool IsCtor); |
| |
| /// Emit an alignment directive to the specified power of two boundary. If a |
| /// global value is specified, and if that global has an explicit alignment |
| /// requested, it will override the alignment request if required for |
| /// correctness. |
| void emitAlignment(Align Alignment, const GlobalObject *GV = nullptr, |
| unsigned MaxBytesToEmit = 0) const; |
| |
| /// Lower the specified LLVM Constant to an MCExpr. |
| virtual const MCExpr *lowerConstant(const Constant *CV); |
| |
| /// Print a general LLVM constant to the .s file. |
| /// On AIX, when an alias refers to a sub-element of a global variable, the |
| /// label of that alias needs to be emitted before the corresponding element. |
| using AliasMapTy = DenseMap<uint64_t, SmallVector<const GlobalAlias *, 1>>; |
| void emitGlobalConstant(const DataLayout &DL, const Constant *CV, |
| AliasMapTy *AliasList = nullptr); |
| |
| /// Unnamed constant global variables solely contaning a pointer to |
| /// another globals variable act like a global variable "proxy", or GOT |
| /// equivalents, i.e., it's only used to hold the address of the latter. One |
| /// optimization is to replace accesses to these proxies by using the GOT |
| /// entry for the final global instead. Hence, we select GOT equivalent |
| /// candidates among all the module global variables, avoid emitting them |
| /// unnecessarily and finally replace references to them by pc relative |
| /// accesses to GOT entries. |
| void computeGlobalGOTEquivs(Module &M); |
| |
| /// Constant expressions using GOT equivalent globals may not be |
| /// eligible for PC relative GOT entry conversion, in such cases we need to |
| /// emit the proxies we previously omitted in EmitGlobalVariable. |
| void emitGlobalGOTEquivs(); |
| |
| /// Emit the stack maps. |
| void emitStackMaps(); |
| |
| //===------------------------------------------------------------------===// |
| // Overridable Hooks |
| //===------------------------------------------------------------------===// |
| |
| void addAsmPrinterHandler(HandlerInfo Handler) { |
| Handlers.insert(Handlers.begin(), std::move(Handler)); |
| NumUserHandlers++; |
| } |
| |
| // Targets can, or in the case of EmitInstruction, must implement these to |
| // customize output. |
| |
| /// This virtual method can be overridden by targets that want to emit |
| /// something at the start of their file. |
| virtual void emitStartOfAsmFile(Module &) {} |
| |
| /// This virtual method can be overridden by targets that want to emit |
| /// something at the end of their file. |
| virtual void emitEndOfAsmFile(Module &) {} |
| |
| /// Targets can override this to emit stuff before the first basic block in |
| /// the function. |
| virtual void emitFunctionBodyStart() {} |
| |
| /// Targets can override this to emit stuff after the last basic block in the |
| /// function. |
| virtual void emitFunctionBodyEnd() {} |
| |
| /// Targets can override this to emit stuff at the start of a basic block. |
| /// By default, this method prints the label for the specified |
| /// MachineBasicBlock, an alignment (if present) and a comment describing it |
| /// if appropriate. |
| virtual void emitBasicBlockStart(const MachineBasicBlock &MBB); |
| |
| /// Targets can override this to emit stuff at the end of a basic block. |
| virtual void emitBasicBlockEnd(const MachineBasicBlock &MBB); |
| |
| /// Targets should implement this to emit instructions. |
| virtual void emitInstruction(const MachineInstr *) { |
| llvm_unreachable("EmitInstruction not implemented"); |
| } |
| |
| /// Return the symbol for the specified constant pool entry. |
| virtual MCSymbol *GetCPISymbol(unsigned CPID) const; |
| |
| virtual void emitFunctionEntryLabel(); |
| |
| virtual void emitFunctionDescriptor() { |
| llvm_unreachable("Function descriptor is target-specific."); |
| } |
| |
| virtual void emitMachineConstantPoolValue(MachineConstantPoolValue *MCPV); |
| |
| /// Targets can override this to change how global constants that are part of |
| /// a C++ static/global constructor list are emitted. |
| virtual void emitXXStructor(const DataLayout &DL, const Constant *CV) { |
| emitGlobalConstant(DL, CV); |
| } |
| |
| /// Return true if the basic block has exactly one predecessor and the control |
| /// transfer mechanism between the predecessor and this block is a |
| /// fall-through. |
| virtual bool |
| isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const; |
| |
| /// Targets can override this to customize the output of IMPLICIT_DEF |
| /// instructions in verbose mode. |
| virtual void emitImplicitDef(const MachineInstr *MI) const; |
| |
| /// Emit N NOP instructions. |
| void emitNops(unsigned N); |
| |
| //===------------------------------------------------------------------===// |
| // Symbol Lowering Routines. |
| //===------------------------------------------------------------------===// |
| |
| MCSymbol *createTempSymbol(const Twine &Name) const; |
| |
| /// Return the MCSymbol for a private symbol with global value name as its |
| /// base, with the specified suffix. |
| MCSymbol *getSymbolWithGlobalValueBase(const GlobalValue *GV, |
| StringRef Suffix) const; |
| |
| /// Return the MCSymbol for the specified ExternalSymbol. |
| MCSymbol *GetExternalSymbolSymbol(StringRef Sym) const; |
| |
| /// Return the symbol for the specified jump table entry. |
| MCSymbol *GetJTISymbol(unsigned JTID, bool isLinkerPrivate = false) const; |
| |
| /// Return the symbol for the specified jump table .set |
| /// FIXME: privatize to AsmPrinter. |
| MCSymbol *GetJTSetSymbol(unsigned UID, unsigned MBBID) const; |
| |
| /// Return the MCSymbol used to satisfy BlockAddress uses of the specified |
| /// basic block. |
| MCSymbol *GetBlockAddressSymbol(const BlockAddress *BA) const; |
| MCSymbol *GetBlockAddressSymbol(const BasicBlock *BB) const; |
| |
| //===------------------------------------------------------------------===// |
| // Emission Helper Routines. |
| //===------------------------------------------------------------------===// |
| |
| /// This is just convenient handler for printing offsets. |
| void printOffset(int64_t Offset, raw_ostream &OS) const; |
| |
| /// Emit a byte directive and value. |
| void emitInt8(int Value) const; |
| |
| /// Emit a short directive and value. |
| void emitInt16(int Value) const; |
| |
| /// Emit a long directive and value. |
| void emitInt32(int Value) const; |
| |
| /// Emit a long long directive and value. |
| void emitInt64(uint64_t Value) const; |
| |
| /// Emit the specified signed leb128 value. |
| void emitSLEB128(int64_t Value, const char *Desc = nullptr) const; |
| |
| /// Emit the specified unsigned leb128 value. |
| void emitULEB128(uint64_t Value, const char *Desc = nullptr, |
| unsigned PadTo = 0) const; |
| |
| /// Emit something like ".long Hi-Lo" where the size in bytes of the directive |
| /// is specified by Size and Hi/Lo specify the labels. This implicitly uses |
| /// .set if it is available. |
| void emitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, |
| unsigned Size) const; |
| |
| /// Emit something like ".uleb128 Hi-Lo". |
| void emitLabelDifferenceAsULEB128(const MCSymbol *Hi, |
| const MCSymbol *Lo) const; |
| |
| /// Emit something like ".long Label+Offset" where the size in bytes of the |
| /// directive is specified by Size and Label specifies the label. This |
| /// implicitly uses .set if it is available. |
| void emitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset, |
| unsigned Size, bool IsSectionRelative = false) const; |
| |
| /// Emit something like ".long Label" where the size in bytes of the directive |
| /// is specified by Size and Label specifies the label. |
| void emitLabelReference(const MCSymbol *Label, unsigned Size, |
| bool IsSectionRelative = false) const { |
| emitLabelPlusOffset(Label, 0, Size, IsSectionRelative); |
| } |
| |
| //===------------------------------------------------------------------===// |
| // Dwarf Emission Helper Routines |
| //===------------------------------------------------------------------===// |
| |
| /// Emit a .byte 42 directive that corresponds to an encoding. If verbose |
| /// assembly output is enabled, we output comments describing the encoding. |
| /// Desc is a string saying what the encoding is specifying (e.g. "LSDA"). |
| void emitEncodingByte(unsigned Val, const char *Desc = nullptr) const; |
| |
| /// Return the size of the encoding in bytes. |
| unsigned GetSizeOfEncodedValue(unsigned Encoding) const; |
| |
| /// Emit reference to a ttype global with a specified encoding. |
| virtual void emitTTypeReference(const GlobalValue *GV, unsigned Encoding); |
| |
| /// Emit a reference to a symbol for use in dwarf. Different object formats |
| /// represent this in different ways. Some use a relocation others encode |
| /// the label offset in its section. |
| void emitDwarfSymbolReference(const MCSymbol *Label, |
| bool ForceOffset = false) const; |
| |
| /// Emit the 4- or 8-byte offset of a string from the start of its section. |
| /// |
| /// When possible, emit a DwarfStringPool section offset without any |
| /// relocations, and without using the symbol. Otherwise, defers to \a |
| /// emitDwarfSymbolReference(). |
| /// |
| /// The length of the emitted value depends on the DWARF format. |
| void emitDwarfStringOffset(DwarfStringPoolEntry S) const; |
| |
| /// Emit the 4-or 8-byte offset of a string from the start of its section. |
| void emitDwarfStringOffset(DwarfStringPoolEntryRef S) const { |
| emitDwarfStringOffset(S.getEntry()); |
| } |
| |
| /// Emit something like ".long Label + Offset" or ".quad Label + Offset" |
| /// depending on the DWARF format. |
| void emitDwarfOffset(const MCSymbol *Label, uint64_t Offset) const; |
| |
| /// Emit 32- or 64-bit value depending on the DWARF format. |
| void emitDwarfLengthOrOffset(uint64_t Value) const; |
| |
| /// Emit a unit length field. The actual format, DWARF32 or DWARF64, is chosen |
| /// according to the settings. |
| void emitDwarfUnitLength(uint64_t Length, const Twine &Comment) const; |
| |
| /// Emit a unit length field. The actual format, DWARF32 or DWARF64, is chosen |
| /// according to the settings. |
| /// Return the end symbol generated inside, the caller needs to emit it. |
| MCSymbol *emitDwarfUnitLength(const Twine &Prefix, |
| const Twine &Comment) const; |
| |
| /// Emit reference to a call site with a specified encoding |
| void emitCallSiteOffset(const MCSymbol *Hi, const MCSymbol *Lo, |
| unsigned Encoding) const; |
| /// Emit an integer value corresponding to the call site encoding |
| void emitCallSiteValue(uint64_t Value, unsigned Encoding) const; |
| |
| /// Get the value for DW_AT_APPLE_isa. Zero if no isa encoding specified. |
| virtual unsigned getISAEncoding() { return 0; } |
| |
| /// Emit the directive and value for debug thread local expression |
| /// |
| /// \p Value - The value to emit. |
| /// \p Size - The size of the integer (in bytes) to emit. |
| virtual void emitDebugValue(const MCExpr *Value, unsigned Size) const; |
| |
| //===------------------------------------------------------------------===// |
| // Dwarf Lowering Routines |
| //===------------------------------------------------------------------===// |
| |
| /// Emit frame instruction to describe the layout of the frame. |
| void emitCFIInstruction(const MCCFIInstruction &Inst) const; |
| |
| /// Emit Dwarf abbreviation table. |
| template <typename T> void emitDwarfAbbrevs(const T &Abbrevs) const { |
| // For each abbreviation. |
| for (const auto &Abbrev : Abbrevs) |
| emitDwarfAbbrev(*Abbrev); |
| |
| // Mark end of abbreviations. |
| emitULEB128(0, "EOM(3)"); |
| } |
| |
| void emitDwarfAbbrev(const DIEAbbrev &Abbrev) const; |
| |
| /// Recursively emit Dwarf DIE tree. |
| void emitDwarfDIE(const DIE &Die) const; |
| |
| //===------------------------------------------------------------------===// |
| // Inline Asm Support |
| //===------------------------------------------------------------------===// |
| |
| // These are hooks that targets can override to implement inline asm |
| // support. These should probably be moved out of AsmPrinter someday. |
| |
| /// Print information related to the specified machine instr that is |
| /// independent of the operand, and may be independent of the instr itself. |
| /// This can be useful for portably encoding the comment character or other |
| /// bits of target-specific knowledge into the asmstrings. The syntax used is |
| /// ${:comment}. Targets can override this to add support for their own |
| /// strange codes. |
| virtual void PrintSpecial(const MachineInstr *MI, raw_ostream &OS, |
| StringRef Code) const; |
| |
| /// Print the MachineOperand as a symbol. Targets with complex handling of |
| /// symbol references should override the base implementation. |
| virtual void PrintSymbolOperand(const MachineOperand &MO, raw_ostream &OS); |
| |
| /// Print the specified operand of MI, an INLINEASM instruction, using the |
| /// specified assembler variant. Targets should override this to format as |
| /// appropriate. This method can return true if the operand is erroneous. |
| virtual bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, |
| const char *ExtraCode, raw_ostream &OS); |
| |
| /// Print the specified operand of MI, an INLINEASM instruction, using the |
| /// specified assembler variant as an address. Targets should override this to |
| /// format as appropriate. This method can return true if the operand is |
| /// erroneous. |
| virtual bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, |
| const char *ExtraCode, raw_ostream &OS); |
| |
| /// Let the target do anything it needs to do before emitting inlineasm. |
| /// \p StartInfo - the subtarget info before parsing inline asm |
| virtual void emitInlineAsmStart() const; |
| |
| /// Let the target do anything it needs to do after emitting inlineasm. |
| /// This callback can be used restore the original mode in case the |
| /// inlineasm contains directives to switch modes. |
| /// \p StartInfo - the original subtarget info before inline asm |
| /// \p EndInfo - the final subtarget info after parsing the inline asm, |
| /// or NULL if the value is unknown. |
| virtual void emitInlineAsmEnd(const MCSubtargetInfo &StartInfo, |
| const MCSubtargetInfo *EndInfo) const; |
| |
| /// This emits visibility information about symbol, if this is supported by |
| /// the target. |
| void emitVisibility(MCSymbol *Sym, unsigned Visibility, |
| bool IsDefinition = true) const; |
| |
| /// This emits linkage information about \p GVSym based on \p GV, if this is |
| /// supported by the target. |
| virtual void emitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const; |
| |
| /// Return the alignment for the specified \p GV. |
| static Align getGVAlignment(const GlobalObject *GV, const DataLayout &DL, |
| Align InAlign = Align(1)); |
| |
| private: |
| /// Private state for PrintSpecial() |
| // Assign a unique ID to this machine instruction. |
| mutable const MachineInstr *LastMI = nullptr; |
| mutable unsigned LastFn = 0; |
| mutable unsigned Counter = ~0U; |
| |
| bool DwarfUsesRelocationsAcrossSections = false; |
| |
| /// This method emits the header for the current function. |
| virtual void emitFunctionHeader(); |
| |
| /// This method emits a comment next to header for the current function. |
| virtual void emitFunctionHeaderComment(); |
| |
| /// Emit a blob of inline asm to the output streamer. |
| void |
| emitInlineAsm(StringRef Str, const MCSubtargetInfo &STI, |
| const MCTargetOptions &MCOptions, |
| const MDNode *LocMDNode = nullptr, |
| InlineAsm::AsmDialect AsmDialect = InlineAsm::AD_ATT) const; |
| |
| /// This method formats and emits the specified machine instruction that is an |
| /// inline asm. |
| void emitInlineAsm(const MachineInstr *MI) const; |
| |
| /// Add inline assembly info to the diagnostics machinery, so we can |
| /// emit file and position info. Returns SrcMgr memory buffer position. |
| unsigned addInlineAsmDiagBuffer(StringRef AsmStr, |
| const MDNode *LocMDNode) const; |
| |
| //===------------------------------------------------------------------===// |
| // Internal Implementation Details |
| //===------------------------------------------------------------------===// |
| |
| void emitJumpTableEntry(const MachineJumpTableInfo *MJTI, |
| const MachineBasicBlock *MBB, unsigned uid) const; |
| void emitLLVMUsedList(const ConstantArray *InitList); |
| /// Emit llvm.ident metadata in an '.ident' directive. |
| void emitModuleIdents(Module &M); |
| /// Emit bytes for llvm.commandline metadata. |
| void emitModuleCommandLines(Module &M); |
| |
| GCMetadataPrinter *getOrCreateGCPrinter(GCStrategy &S); |
| void emitGlobalAlias(Module &M, const GlobalAlias &GA); |
| void emitGlobalIFunc(Module &M, const GlobalIFunc &GI); |
| |
| /// This method decides whether the specified basic block requires a label. |
| bool shouldEmitLabelForBasicBlock(const MachineBasicBlock &MBB) const; |
| |
| protected: |
| virtual bool shouldEmitWeakSwiftAsyncExtendedFramePointerFlags() const { |
| return false; |
| } |
| }; |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_CODEGEN_ASMPRINTER_H |