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//===- llvm/CodeGen/MachineFunction.h ---------------------------*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// Collect native machine code for a function. This class contains a list of
// MachineBasicBlock instances that make up the current compiled function.
// This class also contains pointers to various classes which hold
// target-specific information about the generated code.
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/iterator.h"
#include "llvm/Analysis/EHPersonalities.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/ArrayRecycler.h"
#include "llvm/Support/AtomicOrdering.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Recycler.h"
#include "llvm/Target/TargetMachine.h"
#include <cassert>
#include <cstdint>
#include <memory>
#include <utility>
#include <vector>
namespace llvm {
class BasicBlock;
class BlockAddress;
class DataLayout;
class DebugLoc;
class DIExpression;
class DILocalVariable;
class DILocation;
class Function;
class GlobalValue;
class LLVMTargetMachine;
class MachineConstantPool;
class MachineFrameInfo;
class MachineFunction;
class MachineJumpTableInfo;
class MachineModuleInfo;
class MachineRegisterInfo;
class MCContext;
class MCInstrDesc;
class MCSymbol;
class Pass;
class PseudoSourceValueManager;
class raw_ostream;
class SlotIndexes;
class TargetRegisterClass;
class TargetSubtargetInfo;
struct WasmEHFuncInfo;
struct WinEHFuncInfo;
template <> struct ilist_alloc_traits<MachineBasicBlock> {
void deleteNode(MachineBasicBlock *MBB);
template <> struct ilist_callback_traits<MachineBasicBlock> {
void addNodeToList(MachineBasicBlock* N);
void removeNodeFromList(MachineBasicBlock* N);
template <class Iterator>
void transferNodesFromList(ilist_callback_traits &OldList, Iterator, Iterator) {
assert(this == &OldList && "never transfer MBBs between functions");
/// MachineFunctionInfo - This class can be derived from and used by targets to
/// hold private target-specific information for each MachineFunction. Objects
/// of type are accessed/created with MF::getInfo and destroyed when the
/// MachineFunction is destroyed.
struct MachineFunctionInfo {
virtual ~MachineFunctionInfo();
/// Factory function: default behavior is to call new using the
/// supplied allocator.
/// This function can be overridden in a derive class.
template<typename Ty>
static Ty *create(BumpPtrAllocator &Allocator, MachineFunction &MF) {
return new (Allocator.Allocate<Ty>()) Ty(MF);
/// Properties which a MachineFunction may have at a given point in time.
/// Each of these has checking code in the MachineVerifier, and passes can
/// require that a property be set.
class MachineFunctionProperties {
// Possible TODO: Allow targets to extend this (perhaps by allowing the
// constructor to specify the size of the bit vector)
// Possible TODO: Allow requiring the negative (e.g. VRegsAllocated could be
// stated as the negative of "has vregs"
// The properties are stated in "positive" form; i.e. a pass could require
// that the property hold, but not that it does not hold.
// Property descriptions:
// IsSSA: True when the machine function is in SSA form and virtual registers
// have a single def.
// NoPHIs: The machine function does not contain any PHI instruction.
// TracksLiveness: True when tracking register liveness accurately.
// While this property is set, register liveness information in basic block
// live-in lists and machine instruction operands (e.g. kill flags, implicit
// defs) is accurate. This means it can be used to change the code in ways
// that affect the values in registers, for example by the register
// scavenger.
// When this property is clear, liveness is no longer reliable.
// NoVRegs: The machine function does not use any virtual registers.
// Legalized: In GlobalISel: the MachineLegalizer ran and all pre-isel generic
// instructions have been legalized; i.e., all instructions are now one of:
// - generic and always legal (e.g., COPY)
// - target-specific
// - legal pre-isel generic instructions.
// RegBankSelected: In GlobalISel: the RegBankSelect pass ran and all generic
// virtual registers have been assigned to a register bank.
// Selected: In GlobalISel: the InstructionSelect pass ran and all pre-isel
// generic instructions have been eliminated; i.e., all instructions are now
// target-specific or non-pre-isel generic instructions (e.g., COPY).
// Since only pre-isel generic instructions can have generic virtual register
// operands, this also means that all generic virtual registers have been
// constrained to virtual registers (assigned to register classes) and that
// all sizes attached to them have been eliminated.
enum class Property : unsigned {
LastProperty = Selected,
bool hasProperty(Property P) const {
return Properties[static_cast<unsigned>(P)];
MachineFunctionProperties &set(Property P) {
return *this;
MachineFunctionProperties &reset(Property P) {
return *this;
/// Reset all the properties.
MachineFunctionProperties &reset() {
return *this;
MachineFunctionProperties &set(const MachineFunctionProperties &MFP) {
Properties |= MFP.Properties;
return *this;
MachineFunctionProperties &reset(const MachineFunctionProperties &MFP) {
return *this;
// Returns true if all properties set in V (i.e. required by a pass) are set
// in this.
bool verifyRequiredProperties(const MachineFunctionProperties &V) const {
return !V.Properties.test(Properties);
/// Print the MachineFunctionProperties in human-readable form.
void print(raw_ostream &OS) const;
BitVector Properties =
struct SEHHandler {
/// Filter or finally function. Null indicates a catch-all.
const Function *FilterOrFinally;
/// Address of block to recover at. Null for a finally handler.
const BlockAddress *RecoverBA;
/// This structure is used to retain landing pad info for the current function.
struct LandingPadInfo {
MachineBasicBlock *LandingPadBlock; // Landing pad block.
SmallVector<MCSymbol *, 1> BeginLabels; // Labels prior to invoke.
SmallVector<MCSymbol *, 1> EndLabels; // Labels after invoke.
SmallVector<SEHHandler, 1> SEHHandlers; // SEH handlers active at this lpad.
MCSymbol *LandingPadLabel = nullptr; // Label at beginning of landing pad.
std::vector<int> TypeIds; // List of type ids (filters negative).
explicit LandingPadInfo(MachineBasicBlock *MBB)
: LandingPadBlock(MBB) {}
class MachineFunction {
const Function &F;
const LLVMTargetMachine &Target;
const TargetSubtargetInfo *STI;
MCContext &Ctx;
MachineModuleInfo &MMI;
// RegInfo - Information about each register in use in the function.
MachineRegisterInfo *RegInfo;
// Used to keep track of target-specific per-machine function information for
// the target implementation.
MachineFunctionInfo *MFInfo;
// Keep track of objects allocated on the stack.
MachineFrameInfo *FrameInfo;
// Keep track of constants which are spilled to memory
MachineConstantPool *ConstantPool;
// Keep track of jump tables for switch instructions
MachineJumpTableInfo *JumpTableInfo;
// Keeps track of Wasm exception handling related data. This will be null for
// functions that aren't using a wasm EH personality.
WasmEHFuncInfo *WasmEHInfo = nullptr;
// Keeps track of Windows exception handling related data. This will be null
// for functions that aren't using a funclet-based EH personality.
WinEHFuncInfo *WinEHInfo = nullptr;
// Function-level unique numbering for MachineBasicBlocks. When a
// MachineBasicBlock is inserted into a MachineFunction is it automatically
// numbered and this vector keeps track of the mapping from ID's to MBB's.
std::vector<MachineBasicBlock*> MBBNumbering;
// Pool-allocate MachineFunction-lifetime and IR objects.
BumpPtrAllocator Allocator;
// Allocation management for instructions in function.
Recycler<MachineInstr> InstructionRecycler;
// Allocation management for operand arrays on instructions.
ArrayRecycler<MachineOperand> OperandRecycler;
// Allocation management for basic blocks in function.
Recycler<MachineBasicBlock> BasicBlockRecycler;
// List of machine basic blocks in function
using BasicBlockListType = ilist<MachineBasicBlock>;
BasicBlockListType BasicBlocks;
/// FunctionNumber - This provides a unique ID for each function emitted in
/// this translation unit.
unsigned FunctionNumber;
/// Alignment - The alignment of the function.
Align Alignment;
/// ExposesReturnsTwice - True if the function calls setjmp or related
/// functions with attribute "returns twice", but doesn't have
/// the attribute itself.
/// This is used to limit optimizations which cannot reason
/// about the control flow of such functions.
bool ExposesReturnsTwice = false;
/// True if the function includes any inline assembly.
bool HasInlineAsm = false;
/// True if any WinCFI instruction have been emitted in this function.
bool HasWinCFI = false;
/// Current high-level properties of the IR of the function (e.g. is in SSA
/// form or whether registers have been allocated)
MachineFunctionProperties Properties;
// Allocation management for pseudo source values.
std::unique_ptr<PseudoSourceValueManager> PSVManager;
/// List of moves done by a function's prolog. Used to construct frame maps
/// by debug and exception handling consumers.
std::vector<MCCFIInstruction> FrameInstructions;
/// \name Exception Handling
/// \{
/// List of LandingPadInfo describing the landing pad information.
std::vector<LandingPadInfo> LandingPads;
/// Map a landing pad's EH symbol to the call site indexes.
DenseMap<MCSymbol*, SmallVector<unsigned, 4>> LPadToCallSiteMap;
/// Map a landing pad to its index.
DenseMap<const MachineBasicBlock *, unsigned> WasmLPadToIndexMap;
/// Map of invoke call site index values to associated begin EH_LABEL.
DenseMap<MCSymbol*, unsigned> CallSiteMap;
/// CodeView label annotations.
std::vector<std::pair<MCSymbol *, MDNode *>> CodeViewAnnotations;
/// CodeView heapallocsites.
std::vector<std::tuple<MCSymbol *, MCSymbol *, const DIType *>>
bool CallsEHReturn = false;
bool CallsUnwindInit = false;
bool HasEHScopes = false;
bool HasEHFunclets = false;
/// List of C++ TypeInfo used.
std::vector<const GlobalValue *> TypeInfos;
/// List of typeids encoding filters used.
std::vector<unsigned> FilterIds;
/// List of the indices in FilterIds corresponding to filter terminators.
std::vector<unsigned> FilterEnds;
EHPersonality PersonalityTypeCache = EHPersonality::Unknown;
/// \}
/// Clear all the members of this MachineFunction, but the ones used
/// to initialize again the MachineFunction.
/// More specifically, this deallocates all the dynamically allocated
/// objects and get rid of all the XXXInfo data structure, but keep
/// unchanged the references to Fn, Target, MMI, and FunctionNumber.
void clear();
/// Allocate and initialize the different members.
/// In particular, the XXXInfo data structure.
/// \pre Fn, Target, MMI, and FunctionNumber are properly set.
void init();
struct VariableDbgInfo {
const DILocalVariable *Var;
const DIExpression *Expr;
// The Slot can be negative for fixed stack objects.
int Slot;
const DILocation *Loc;
VariableDbgInfo(const DILocalVariable *Var, const DIExpression *Expr,
int Slot, const DILocation *Loc)
: Var(Var), Expr(Expr), Slot(Slot), Loc(Loc) {}
class Delegate {
virtual void anchor();
virtual ~Delegate() = default;
/// Callback after an insertion. This should not modify the MI directly.
virtual void MF_HandleInsertion(MachineInstr &MI) = 0;
/// Callback before a removal. This should not modify the MI directly.
virtual void MF_HandleRemoval(MachineInstr &MI) = 0;
/// Structure used to represent pair of argument number after call lowering
/// and register used to transfer that argument.
/// For now we support only cases when argument is transferred through one
/// register.
struct ArgRegPair {
unsigned Reg;
uint16_t ArgNo;
ArgRegPair(unsigned R, unsigned Arg) : Reg(R), ArgNo(Arg) {
assert(Arg < (1 << 16) && "Arg out of range");
/// Vector of call argument and its forwarding register.
using CallSiteInfo = SmallVector<ArgRegPair, 1>;
using CallSiteInfoImpl = SmallVectorImpl<ArgRegPair>;
Delegate *TheDelegate = nullptr;
using CallSiteInfoMap = DenseMap<const MachineInstr *, CallSiteInfo>;
/// Map a call instruction to call site arguments forwarding info.
CallSiteInfoMap CallSitesInfo;
/// A helper function that returns call site info for a give call
/// instruction if debug entry value support is enabled.
CallSiteInfoMap::iterator getCallSiteInfo(const MachineInstr *MI) {
assert(MI->isCall() &&
"Call site info refers only to call instructions!");
if (!Target.Options.EnableDebugEntryValues)
return CallSitesInfo.end();
return CallSitesInfo.find(MI);
// Callbacks for insertion and removal.
void handleInsertion(MachineInstr &MI);
void handleRemoval(MachineInstr &MI);
friend struct ilist_traits<MachineInstr>;
using VariableDbgInfoMapTy = SmallVector<VariableDbgInfo, 4>;
VariableDbgInfoMapTy VariableDbgInfos;
MachineFunction(const Function &F, const LLVMTargetMachine &Target,
const TargetSubtargetInfo &STI, unsigned FunctionNum,
MachineModuleInfo &MMI);
MachineFunction(const MachineFunction &) = delete;
MachineFunction &operator=(const MachineFunction &) = delete;
/// Reset the instance as if it was just created.
void reset() {
/// Reset the currently registered delegate - otherwise assert.
void resetDelegate(Delegate *delegate) {
assert(TheDelegate == delegate &&
"Only the current delegate can perform reset!");
TheDelegate = nullptr;
/// Set the delegate. resetDelegate must be called before attempting
/// to set.
void setDelegate(Delegate *delegate) {
assert(delegate && !TheDelegate &&
"Attempted to set delegate to null, or to change it without "
"first resetting it!");
TheDelegate = delegate;
MachineModuleInfo &getMMI() const { return MMI; }
MCContext &getContext() const { return Ctx; }
PseudoSourceValueManager &getPSVManager() const { return *PSVManager; }
/// Return the DataLayout attached to the Module associated to this MF.
const DataLayout &getDataLayout() const;
/// Return the LLVM function that this machine code represents
const Function &getFunction() const { return F; }
/// getName - Return the name of the corresponding LLVM function.
StringRef getName() const;
/// getFunctionNumber - Return a unique ID for the current function.
unsigned getFunctionNumber() const { return FunctionNumber; }
/// getTarget - Return the target machine this machine code is compiled with
const LLVMTargetMachine &getTarget() const { return Target; }
/// getSubtarget - Return the subtarget for which this machine code is being
/// compiled.
const TargetSubtargetInfo &getSubtarget() const { return *STI; }
/// getSubtarget - This method returns a pointer to the specified type of
/// TargetSubtargetInfo. In debug builds, it verifies that the object being
/// returned is of the correct type.
template<typename STC> const STC &getSubtarget() const {
return *static_cast<const STC *>(STI);
/// getRegInfo - Return information about the registers currently in use.
MachineRegisterInfo &getRegInfo() { return *RegInfo; }
const MachineRegisterInfo &getRegInfo() const { return *RegInfo; }
/// getFrameInfo - Return the frame info object for the current function.
/// This object contains information about objects allocated on the stack
/// frame of the current function in an abstract way.
MachineFrameInfo &getFrameInfo() { return *FrameInfo; }
const MachineFrameInfo &getFrameInfo() const { return *FrameInfo; }
/// getJumpTableInfo - Return the jump table info object for the current
/// function. This object contains information about jump tables in the
/// current function. If the current function has no jump tables, this will
/// return null.
const MachineJumpTableInfo *getJumpTableInfo() const { return JumpTableInfo; }
MachineJumpTableInfo *getJumpTableInfo() { return JumpTableInfo; }
/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it
/// does already exist, allocate one.
MachineJumpTableInfo *getOrCreateJumpTableInfo(unsigned JTEntryKind);
/// getConstantPool - Return the constant pool object for the current
/// function.
MachineConstantPool *getConstantPool() { return ConstantPool; }
const MachineConstantPool *getConstantPool() const { return ConstantPool; }
/// getWasmEHFuncInfo - Return information about how the current function uses
/// Wasm exception handling. Returns null for functions that don't use wasm
/// exception handling.
const WasmEHFuncInfo *getWasmEHFuncInfo() const { return WasmEHInfo; }
WasmEHFuncInfo *getWasmEHFuncInfo() { return WasmEHInfo; }
/// getWinEHFuncInfo - Return information about how the current function uses
/// Windows exception handling. Returns null for functions that don't use
/// funclets for exception handling.
const WinEHFuncInfo *getWinEHFuncInfo() const { return WinEHInfo; }
WinEHFuncInfo *getWinEHFuncInfo() { return WinEHInfo; }
/// getAlignment - Return the alignment of the function.
Align getAlignment() const { return Alignment; }
/// setAlignment - Set the alignment of the function.
void setAlignment(Align A) { Alignment = A; }
/// ensureAlignment - Make sure the function is at least A bytes aligned.
void ensureAlignment(Align A) {
if (Alignment < A)
Alignment = A;
/// exposesReturnsTwice - Returns true if the function calls setjmp or
/// any other similar functions with attribute "returns twice" without
/// having the attribute itself.
bool exposesReturnsTwice() const {
return ExposesReturnsTwice;
/// setCallsSetJmp - Set a flag that indicates if there's a call to
/// a "returns twice" function.
void setExposesReturnsTwice(bool B) {
ExposesReturnsTwice = B;
/// Returns true if the function contains any inline assembly.
bool hasInlineAsm() const {
return HasInlineAsm;
/// Set a flag that indicates that the function contains inline assembly.
void setHasInlineAsm(bool B) {
HasInlineAsm = B;
bool hasWinCFI() const {
return HasWinCFI;
void setHasWinCFI(bool v) { HasWinCFI = v; }
/// Get the function properties
const MachineFunctionProperties &getProperties() const { return Properties; }
MachineFunctionProperties &getProperties() { return Properties; }
/// getInfo - Keep track of various per-function pieces of information for
/// backends that would like to do so.
template<typename Ty>
Ty *getInfo() {
if (!MFInfo)
MFInfo = Ty::template create<Ty>(Allocator, *this);
return static_cast<Ty*>(MFInfo);
template<typename Ty>
const Ty *getInfo() const {
return const_cast<MachineFunction*>(this)->getInfo<Ty>();
/// getBlockNumbered - MachineBasicBlocks are automatically numbered when they
/// are inserted into the machine function. The block number for a machine
/// basic block can be found by using the MBB::getNumber method, this method
/// provides the inverse mapping.
MachineBasicBlock *getBlockNumbered(unsigned N) const {
assert(N < MBBNumbering.size() && "Illegal block number");
assert(MBBNumbering[N] && "Block was removed from the machine function!");
return MBBNumbering[N];
/// Should we be emitting segmented stack stuff for the function
bool shouldSplitStack() const;
/// getNumBlockIDs - Return the number of MBB ID's allocated.
unsigned getNumBlockIDs() const { return (unsigned)MBBNumbering.size(); }
/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
/// recomputes them. This guarantees that the MBB numbers are sequential,
/// dense, and match the ordering of the blocks within the function. If a
/// specific MachineBasicBlock is specified, only that block and those after
/// it are renumbered.
void RenumberBlocks(MachineBasicBlock *MBBFrom = nullptr);
/// print - Print out the MachineFunction in a format suitable for debugging
/// to the specified stream.
void print(raw_ostream &OS, const SlotIndexes* = nullptr) const;
/// viewCFG - This function is meant for use from the debugger. You can just
/// say 'call F->viewCFG()' and a ghostview window should pop up from the
/// program, displaying the CFG of the current function with the code for each
/// basic block inside. This depends on there being a 'dot' and 'gv' program
/// in your path.
void viewCFG() const;
/// viewCFGOnly - This function is meant for use from the debugger. It works
/// just like viewCFG, but it does not include the contents of basic blocks
/// into the nodes, just the label. If you are only interested in the CFG
/// this can make the graph smaller.
void viewCFGOnly() const;
/// dump - Print the current MachineFunction to cerr, useful for debugger use.
void dump() const;
/// Run the current MachineFunction through the machine code verifier, useful
/// for debugger use.
/// \returns true if no problems were found.
bool verify(Pass *p = nullptr, const char *Banner = nullptr,
bool AbortOnError = true) const;
// Provide accessors for the MachineBasicBlock list...
using iterator = BasicBlockListType::iterator;
using const_iterator = BasicBlockListType::const_iterator;
using const_reverse_iterator = BasicBlockListType::const_reverse_iterator;
using reverse_iterator = BasicBlockListType::reverse_iterator;
/// Support for MachineBasicBlock::getNextNode().
static BasicBlockListType MachineFunction::*
getSublistAccess(MachineBasicBlock *) {
return &MachineFunction::BasicBlocks;
/// addLiveIn - Add the specified physical register as a live-in value and
/// create a corresponding virtual register for it.
unsigned addLiveIn(unsigned PReg, const TargetRegisterClass *RC);
// BasicBlock accessor functions.
iterator begin() { return BasicBlocks.begin(); }
const_iterator begin() const { return BasicBlocks.begin(); }
iterator end () { return BasicBlocks.end(); }
const_iterator end () const { return BasicBlocks.end(); }
reverse_iterator rbegin() { return BasicBlocks.rbegin(); }
const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); }
reverse_iterator rend () { return BasicBlocks.rend(); }
const_reverse_iterator rend () const { return BasicBlocks.rend(); }
unsigned size() const { return (unsigned)BasicBlocks.size();}
bool empty() const { return BasicBlocks.empty(); }
const MachineBasicBlock &front() const { return BasicBlocks.front(); }
MachineBasicBlock &front() { return BasicBlocks.front(); }
const MachineBasicBlock & back() const { return BasicBlocks.back(); }
MachineBasicBlock & back() { return BasicBlocks.back(); }
void push_back (MachineBasicBlock *MBB) { BasicBlocks.push_back (MBB); }
void push_front(MachineBasicBlock *MBB) { BasicBlocks.push_front(MBB); }
void insert(iterator MBBI, MachineBasicBlock *MBB) {
BasicBlocks.insert(MBBI, MBB);
void splice(iterator InsertPt, iterator MBBI) {
BasicBlocks.splice(InsertPt, BasicBlocks, MBBI);
void splice(iterator InsertPt, MachineBasicBlock *MBB) {
BasicBlocks.splice(InsertPt, BasicBlocks, MBB);
void splice(iterator InsertPt, iterator MBBI, iterator MBBE) {
BasicBlocks.splice(InsertPt, BasicBlocks, MBBI, MBBE);
void remove(iterator MBBI) { BasicBlocks.remove(MBBI); }
void remove(MachineBasicBlock *MBBI) { BasicBlocks.remove(MBBI); }
void erase(iterator MBBI) { BasicBlocks.erase(MBBI); }
void erase(MachineBasicBlock *MBBI) { BasicBlocks.erase(MBBI); }
template <typename Comp>
void sort(Comp comp) {
/// Return the number of \p MachineInstrs in this \p MachineFunction.
unsigned getInstructionCount() const {
unsigned InstrCount = 0;
for (const MachineBasicBlock &MBB : BasicBlocks)
InstrCount += MBB.size();
return InstrCount;
// Internal functions used to automatically number MachineBasicBlocks
/// Adds the MBB to the internal numbering. Returns the unique number
/// assigned to the MBB.
unsigned addToMBBNumbering(MachineBasicBlock *MBB) {
return (unsigned)MBBNumbering.size()-1;
/// removeFromMBBNumbering - Remove the specific machine basic block from our
/// tracker, this is only really to be used by the MachineBasicBlock
/// implementation.
void removeFromMBBNumbering(unsigned N) {
assert(N < MBBNumbering.size() && "Illegal basic block #");
MBBNumbering[N] = nullptr;
/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
/// of `new MachineInstr'.
MachineInstr *CreateMachineInstr(const MCInstrDesc &MCID, const DebugLoc &DL,
bool NoImp = false);
/// Create a new MachineInstr which is a copy of \p Orig, identical in all
/// ways except the instruction has no parent, prev, or next. Bundling flags
/// are reset.
/// Note: Clones a single instruction, not whole instruction bundles.
/// Does not perform target specific adjustments; consider using
/// TargetInstrInfo::duplicate() instead.
MachineInstr *CloneMachineInstr(const MachineInstr *Orig);
/// Clones instruction or the whole instruction bundle \p Orig and insert
/// into \p MBB before \p InsertBefore.
/// Note: Does not perform target specific adjustments; consider using
/// TargetInstrInfo::duplicate() intead.
MachineInstr &CloneMachineInstrBundle(MachineBasicBlock &MBB,
MachineBasicBlock::iterator InsertBefore, const MachineInstr &Orig);
/// DeleteMachineInstr - Delete the given MachineInstr.
void DeleteMachineInstr(MachineInstr *MI);
/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
/// instead of `new MachineBasicBlock'.
MachineBasicBlock *CreateMachineBasicBlock(const BasicBlock *bb = nullptr);
/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
void DeleteMachineBasicBlock(MachineBasicBlock *MBB);
/// getMachineMemOperand - Allocate a new MachineMemOperand.
/// MachineMemOperands are owned by the MachineFunction and need not be
/// explicitly deallocated.
MachineMemOperand *getMachineMemOperand(
MachinePointerInfo PtrInfo, MachineMemOperand::Flags f, uint64_t s,
unsigned base_alignment, const AAMDNodes &AAInfo = AAMDNodes(),
const MDNode *Ranges = nullptr,
SyncScope::ID SSID = SyncScope::System,
AtomicOrdering Ordering = AtomicOrdering::NotAtomic,
AtomicOrdering FailureOrdering = AtomicOrdering::NotAtomic);
/// getMachineMemOperand - Allocate a new MachineMemOperand by copying
/// an existing one, adjusting by an offset and using the given size.
/// MachineMemOperands are owned by the MachineFunction and need not be
/// explicitly deallocated.
MachineMemOperand *getMachineMemOperand(const MachineMemOperand *MMO,
int64_t Offset, uint64_t Size);
/// Allocate a new MachineMemOperand by copying an existing one,
/// replacing only AliasAnalysis information. MachineMemOperands are owned
/// by the MachineFunction and need not be explicitly deallocated.
MachineMemOperand *getMachineMemOperand(const MachineMemOperand *MMO,
const AAMDNodes &AAInfo);
/// Allocate a new MachineMemOperand by copying an existing one,
/// replacing the flags. MachineMemOperands are owned
/// by the MachineFunction and need not be explicitly deallocated.
MachineMemOperand *getMachineMemOperand(const MachineMemOperand *MMO,
MachineMemOperand::Flags Flags);
using OperandCapacity = ArrayRecycler<MachineOperand>::Capacity;
/// Allocate an array of MachineOperands. This is only intended for use by
/// internal MachineInstr functions.
MachineOperand *allocateOperandArray(OperandCapacity Cap) {
return OperandRecycler.allocate(Cap, Allocator);
/// Dellocate an array of MachineOperands and recycle the memory. This is
/// only intended for use by internal MachineInstr functions.
/// Cap must be the same capacity that was used to allocate the array.
void deallocateOperandArray(OperandCapacity Cap, MachineOperand *Array) {
OperandRecycler.deallocate(Cap, Array);
/// Allocate and initialize a register mask with @p NumRegister bits.
uint32_t *allocateRegMask();
/// Allocate and construct an extra info structure for a `MachineInstr`.
/// This is allocated on the function's allocator and so lives the life of
/// the function.
MachineInstr::ExtraInfo *
createMIExtraInfo(ArrayRef<MachineMemOperand *> MMOs,
MCSymbol *PreInstrSymbol = nullptr,
MCSymbol *PostInstrSymbol = nullptr);
/// Allocate a string and populate it with the given external symbol name.
const char *createExternalSymbolName(StringRef Name);
// Label Manipulation.
/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table.
/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
/// normal 'L' label is returned.
MCSymbol *getJTISymbol(unsigned JTI, MCContext &Ctx,
bool isLinkerPrivate = false) const;
/// getPICBaseSymbol - Return a function-local symbol to represent the PIC
/// base.
MCSymbol *getPICBaseSymbol() const;
/// Returns a reference to a list of cfi instructions in the function's
/// prologue. Used to construct frame maps for debug and exception handling
/// comsumers.
const std::vector<MCCFIInstruction> &getFrameInstructions() const {
return FrameInstructions;
LLVM_NODISCARD unsigned addFrameInst(const MCCFIInstruction &Inst);
/// \name Exception Handling
/// \{
bool callsEHReturn() const { return CallsEHReturn; }
void setCallsEHReturn(bool b) { CallsEHReturn = b; }
bool callsUnwindInit() const { return CallsUnwindInit; }
void setCallsUnwindInit(bool b) { CallsUnwindInit = b; }
bool hasEHScopes() const { return HasEHScopes; }
void setHasEHScopes(bool V) { HasEHScopes = V; }
bool hasEHFunclets() const { return HasEHFunclets; }
void setHasEHFunclets(bool V) { HasEHFunclets = V; }
/// Find or create an LandingPadInfo for the specified MachineBasicBlock.
LandingPadInfo &getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad);
/// Remap landing pad labels and remove any deleted landing pads.
void tidyLandingPads(DenseMap<MCSymbol *, uintptr_t> *LPMap = nullptr,
bool TidyIfNoBeginLabels = true);
/// Return a reference to the landing pad info for the current function.
const std::vector<LandingPadInfo> &getLandingPads() const {
return LandingPads;
/// Provide the begin and end labels of an invoke style call and associate it
/// with a try landing pad block.
void addInvoke(MachineBasicBlock *LandingPad,
MCSymbol *BeginLabel, MCSymbol *EndLabel);
/// Add a new panding pad, and extract the exception handling information from
/// the landingpad instruction. Returns the label ID for the landing pad
/// entry.
MCSymbol *addLandingPad(MachineBasicBlock *LandingPad);
/// Provide the catch typeinfo for a landing pad.
void addCatchTypeInfo(MachineBasicBlock *LandingPad,
ArrayRef<const GlobalValue *> TyInfo);
/// Provide the filter typeinfo for a landing pad.
void addFilterTypeInfo(MachineBasicBlock *LandingPad,
ArrayRef<const GlobalValue *> TyInfo);
/// Add a cleanup action for a landing pad.
void addCleanup(MachineBasicBlock *LandingPad);
void addSEHCatchHandler(MachineBasicBlock *LandingPad, const Function *Filter,
const BlockAddress *RecoverBA);
void addSEHCleanupHandler(MachineBasicBlock *LandingPad,
const Function *Cleanup);
/// Return the type id for the specified typeinfo. This is function wide.
unsigned getTypeIDFor(const GlobalValue *TI);
/// Return the id of the filter encoded by TyIds. This is function wide.
int getFilterIDFor(std::vector<unsigned> &TyIds);
/// Map the landing pad's EH symbol to the call site indexes.
void setCallSiteLandingPad(MCSymbol *Sym, ArrayRef<unsigned> Sites);
/// Map the landing pad to its index. Used for Wasm exception handling.
void setWasmLandingPadIndex(const MachineBasicBlock *LPad, unsigned Index) {
WasmLPadToIndexMap[LPad] = Index;
/// Returns true if the landing pad has an associate index in wasm EH.
bool hasWasmLandingPadIndex(const MachineBasicBlock *LPad) const {
return WasmLPadToIndexMap.count(LPad);
/// Get the index in wasm EH for a given landing pad.
unsigned getWasmLandingPadIndex(const MachineBasicBlock *LPad) const {
return WasmLPadToIndexMap.lookup(LPad);
/// Get the call site indexes for a landing pad EH symbol.
SmallVectorImpl<unsigned> &getCallSiteLandingPad(MCSymbol *Sym) {
assert(hasCallSiteLandingPad(Sym) &&
"missing call site number for landing pad!");
return LPadToCallSiteMap[Sym];
/// Return true if the landing pad Eh symbol has an associated call site.
bool hasCallSiteLandingPad(MCSymbol *Sym) {
return !LPadToCallSiteMap[Sym].empty();
/// Map the begin label for a call site.
void setCallSiteBeginLabel(MCSymbol *BeginLabel, unsigned Site) {
CallSiteMap[BeginLabel] = Site;
/// Get the call site number for a begin label.
unsigned getCallSiteBeginLabel(MCSymbol *BeginLabel) const {
assert(hasCallSiteBeginLabel(BeginLabel) &&
"Missing call site number for EH_LABEL!");
return CallSiteMap.lookup(BeginLabel);
/// Return true if the begin label has a call site number associated with it.
bool hasCallSiteBeginLabel(MCSymbol *BeginLabel) const {
return CallSiteMap.count(BeginLabel);
/// Record annotations associated with a particular label.
void addCodeViewAnnotation(MCSymbol *Label, MDNode *MD) {
CodeViewAnnotations.push_back({Label, MD});
ArrayRef<std::pair<MCSymbol *, MDNode *>> getCodeViewAnnotations() const {
return CodeViewAnnotations;
/// Record heapallocsites
void addCodeViewHeapAllocSite(MachineInstr *I, const MDNode *MD);
ArrayRef<std::tuple<MCSymbol *, MCSymbol *, const DIType *>>
getCodeViewHeapAllocSites() const {
return CodeViewHeapAllocSites;
/// Return a reference to the C++ typeinfo for the current function.
const std::vector<const GlobalValue *> &getTypeInfos() const {
return TypeInfos;
/// Return a reference to the typeids encoding filters used in the current
/// function.
const std::vector<unsigned> &getFilterIds() const {
return FilterIds;
/// \}
/// Collect information used to emit debugging information of a variable.
void setVariableDbgInfo(const DILocalVariable *Var, const DIExpression *Expr,
int Slot, const DILocation *Loc) {
VariableDbgInfos.emplace_back(Var, Expr, Slot, Loc);
VariableDbgInfoMapTy &getVariableDbgInfo() { return VariableDbgInfos; }
const VariableDbgInfoMapTy &getVariableDbgInfo() const {
return VariableDbgInfos;
void addCallArgsForwardingRegs(const MachineInstr *CallI,
CallSiteInfoImpl &&CallInfo) {
CallSitesInfo[CallI] = std::move(CallInfo);
const CallSiteInfoMap &getCallSitesInfo() const {
return CallSitesInfo;
/// Following functions update call site info. They should be called before
/// removing, replacing or copying call instruction.
/// Move the call site info from \p Old to \New call site info. This function
/// is used when we are replacing one call instruction with another one to
/// the same callee.
void moveCallSiteInfo(const MachineInstr *Old,
const MachineInstr *New);
/// Erase the call site info for \p MI. It is used to remove a call
/// instruction from the instruction stream.
void eraseCallSiteInfo(const MachineInstr *MI);
/// Copy the call site info from \p Old to \ New. Its usage is when we are
/// making a copy of the instruction that will be inserted at different point
/// of the instruction stream.
void copyCallSiteInfo(const MachineInstr *Old,
const MachineInstr *New);
// GraphTraits specializations for function basic block graphs (CFGs)
// Provide specializations of GraphTraits to be able to treat a
// machine function as a graph of machine basic blocks... these are
// the same as the machine basic block iterators, except that the root
// node is implicitly the first node of the function.
template <> struct GraphTraits<MachineFunction*> :
public GraphTraits<MachineBasicBlock*> {
static NodeRef getEntryNode(MachineFunction *F) { return &F->front(); }
// nodes_iterator/begin/end - Allow iteration over all nodes in the graph
using nodes_iterator = pointer_iterator<MachineFunction::iterator>;
static nodes_iterator nodes_begin(MachineFunction *F) {
return nodes_iterator(F->begin());
static nodes_iterator nodes_end(MachineFunction *F) {
return nodes_iterator(F->end());
static unsigned size (MachineFunction *F) { return F->size(); }
template <> struct GraphTraits<const MachineFunction*> :
public GraphTraits<const MachineBasicBlock*> {
static NodeRef getEntryNode(const MachineFunction *F) { return &F->front(); }
// nodes_iterator/begin/end - Allow iteration over all nodes in the graph
using nodes_iterator = pointer_iterator<MachineFunction::const_iterator>;
static nodes_iterator nodes_begin(const MachineFunction *F) {
return nodes_iterator(F->begin());
static nodes_iterator nodes_end (const MachineFunction *F) {
return nodes_iterator(F->end());
static unsigned size (const MachineFunction *F) {
return F->size();
// Provide specializations of GraphTraits to be able to treat a function as a
// graph of basic blocks... and to walk it in inverse order. Inverse order for
// a function is considered to be when traversing the predecessor edges of a BB
// instead of the successor edges.
template <> struct GraphTraits<Inverse<MachineFunction*>> :
public GraphTraits<Inverse<MachineBasicBlock*>> {
static NodeRef getEntryNode(Inverse<MachineFunction *> G) {
return &G.Graph->front();
template <> struct GraphTraits<Inverse<const MachineFunction*>> :
public GraphTraits<Inverse<const MachineBasicBlock*>> {
static NodeRef getEntryNode(Inverse<const MachineFunction *> G) {
return &G.Graph->front();
} // end namespace llvm