//===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of the Instruction class, which is the
// base class for all of the LLVM instructions.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_INSTRUCTION_H
#define LLVM_IR_INSTRUCTION_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/IR/SymbolTableListTraits.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
#include <utility>
namespace llvm {
class BasicBlock;
class FastMathFlags;
class MDNode;
struct AAMDNodes;
template <> struct ilist_alloc_traits<Instruction> {
static inline void deleteNode(Instruction *V);
};
class Instruction : public User,
public ilist_node_with_parent<Instruction, BasicBlock> {
BasicBlock *Parent;
DebugLoc DbgLoc; // 'dbg' Metadata cache.
enum {
/// This is a bit stored in the SubClassData field which indicates whether
/// this instruction has metadata attached to it or not.
HasMetadataBit = 1 << 15
};
protected:
~Instruction(); // Use deleteValue() to delete a generic Instruction.
public:
Instruction(const Instruction &) = delete;
Instruction &operator=(const Instruction &) = delete;
/// Specialize the methods defined in Value, as we know that an instruction
/// can only be used by other instructions.
Instruction *user_back() { return cast<Instruction>(*user_begin());}
const Instruction *user_back() const { return cast<Instruction>(*user_begin());}
inline const BasicBlock *getParent() const { return Parent; }
inline BasicBlock *getParent() { return Parent; }
/// Return the module owning the function this instruction belongs to
/// or nullptr it the function does not have a module.
///
/// Note: this is undefined behavior if the instruction does not have a
/// parent, or the parent basic block does not have a parent function.
const Module *getModule() const;
Module *getModule() {
return const_cast<Module *>(
static_cast<const Instruction *>(this)->getModule());
}
/// Return the function this instruction belongs to.
///
/// Note: it is undefined behavior to call this on an instruction not
/// currently inserted into a function.
const Function *getFunction() const;
Function *getFunction() {
return const_cast<Function *>(
static_cast<const Instruction *>(this)->getFunction());
}
/// This method unlinks 'this' from the containing basic block, but does not
/// delete it.
void removeFromParent();
/// This method unlinks 'this' from the containing basic block and deletes it.
///
/// \returns an iterator pointing to the element after the erased one
SymbolTableList<Instruction>::iterator eraseFromParent();
/// Insert an unlinked instruction into a basic block immediately before
/// the specified instruction.
void insertBefore(Instruction *InsertPos);
/// Insert an unlinked instruction into a basic block immediately after the
/// specified instruction.
void insertAfter(Instruction *InsertPos);
/// Unlink this instruction from its current basic block and insert it into
/// the basic block that MovePos lives in, right before MovePos.
void moveBefore(Instruction *MovePos);
/// Unlink this instruction and insert into BB before I.
///
/// \pre I is a valid iterator into BB.
void moveBefore(BasicBlock &BB, SymbolTableList<Instruction>::iterator I);
//===--------------------------------------------------------------------===//
// Subclass classification.
//===--------------------------------------------------------------------===//
/// Returns a member of one of the enums like Instruction::Add.
unsigned getOpcode() const { return getValueID() - InstructionVal; }
const char *getOpcodeName() const { return getOpcodeName(getOpcode()); }
bool isTerminator() const { return isTerminator(getOpcode()); }
bool isBinaryOp() const { return isBinaryOp(getOpcode()); }
bool isShift() { return isShift(getOpcode()); }
bool isCast() const { return isCast(getOpcode()); }
bool isFuncletPad() const { return isFuncletPad(getOpcode()); }
static const char* getOpcodeName(unsigned OpCode);
static inline bool isTerminator(unsigned OpCode) {
return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
}
static inline bool isBinaryOp(unsigned Opcode) {
return Opcode >= BinaryOpsBegin && Opcode < BinaryOpsEnd;
}
/// Determine if the Opcode is one of the shift instructions.
static inline bool isShift(unsigned Opcode) {
return Opcode >= Shl && Opcode <= AShr;
}
/// Return true if this is a logical shift left or a logical shift right.
inline bool isLogicalShift() const {
return getOpcode() == Shl || getOpcode() == LShr;
}
/// Return true if this is an arithmetic shift right.
inline bool isArithmeticShift() const {
return getOpcode() == AShr;
}
/// Return true if this is and/or/xor.
inline bool isBitwiseLogicOp() const {
return getOpcode() == And || getOpcode() == Or || getOpcode() == Xor;
}
/// Determine if the OpCode is one of the CastInst instructions.
static inline bool isCast(unsigned OpCode) {
return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
}
/// Determine if the OpCode is one of the FuncletPadInst instructions.
static inline bool isFuncletPad(unsigned OpCode) {
return OpCode >= FuncletPadOpsBegin && OpCode < FuncletPadOpsEnd;
}
//===--------------------------------------------------------------------===//
// Metadata manipulation.
//===--------------------------------------------------------------------===//
/// Return true if this instruction has any metadata attached to it.
bool hasMetadata() const { return DbgLoc || hasMetadataHashEntry(); }
/// Return true if this instruction has metadata attached to it other than a
/// debug location.
bool hasMetadataOtherThanDebugLoc() const {
return hasMetadataHashEntry();
}
/// Get the metadata of given kind attached to this Instruction.
/// If the metadata is not found then return null.
MDNode *getMetadata(unsigned KindID) const {
if (!hasMetadata()) return nullptr;
return getMetadataImpl(KindID);
}
/// Get the metadata of given kind attached to this Instruction.
/// If the metadata is not found then return null.
MDNode *getMetadata(StringRef Kind) const {
if (!hasMetadata()) return nullptr;
return getMetadataImpl(Kind);
}
/// Get all metadata attached to this Instruction. The first element of each
/// pair returned is the KindID, the second element is the metadata value.
/// This list is returned sorted by the KindID.
void
getAllMetadata(SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
if (hasMetadata())
getAllMetadataImpl(MDs);
}
/// This does the same thing as getAllMetadata, except that it filters out the
/// debug location.
void getAllMetadataOtherThanDebugLoc(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
if (hasMetadataOtherThanDebugLoc())
getAllMetadataOtherThanDebugLocImpl(MDs);
}
/// Fills the AAMDNodes structure with AA metadata from this instruction.
/// When Merge is true, the existing AA metadata is merged with that from this
/// instruction providing the most-general result.
void getAAMetadata(AAMDNodes &N, bool Merge = false) const;
/// Set the metadata of the specified kind to the specified node. This updates
/// or replaces metadata if already present, or removes it if Node is null.
void setMetadata(unsigned KindID, MDNode *Node);
void setMetadata(StringRef Kind, MDNode *Node);
/// Copy metadata from \p SrcInst to this instruction. \p WL, if not empty,
/// specifies the list of meta data that needs to be copied. If \p WL is
/// empty, all meta data will be copied.
void copyMetadata(const Instruction &SrcInst,
ArrayRef<unsigned> WL = ArrayRef<unsigned>());
/// If the instruction has "branch_weights" MD_prof metadata and the MDNode
/// has three operands (including name string), swap the order of the
/// metadata.
void swapProfMetadata();
/// Drop all unknown metadata except for debug locations.
/// @{
/// Passes are required to drop metadata they don't understand. This is a
/// convenience method for passes to do so.
void dropUnknownNonDebugMetadata(ArrayRef<unsigned> KnownIDs);
void dropUnknownNonDebugMetadata() {
return dropUnknownNonDebugMetadata(None);
}
void dropUnknownNonDebugMetadata(unsigned ID1) {
return dropUnknownNonDebugMetadata(makeArrayRef(ID1));
}
void dropUnknownNonDebugMetadata(unsigned ID1, unsigned ID2) {
unsigned IDs[] = {ID1, ID2};
return dropUnknownNonDebugMetadata(IDs);
}
/// @}
/// Sets the metadata on this instruction from the AAMDNodes structure.
void setAAMetadata(const AAMDNodes &N);
/// Retrieve the raw weight values of a conditional branch or select.
/// Returns true on success with profile weights filled in.
/// Returns false if no metadata or invalid metadata was found.
bool extractProfMetadata(uint64_t &TrueVal, uint64_t &FalseVal) const;
/// Retrieve total raw weight values of a branch.
/// Returns true on success with profile total weights filled in.
/// Returns false if no metadata was found.
bool extractProfTotalWeight(uint64_t &TotalVal) const;
/// Updates branch_weights metadata by scaling it by \p S / \p T.
void updateProfWeight(uint64_t S, uint64_t T);
/// Sets the branch_weights metadata to \p W for CallInst.
void setProfWeight(uint64_t W);
/// Set the debug location information for this instruction.
void setDebugLoc(DebugLoc Loc) { DbgLoc = std::move(Loc); }
/// Return the debug location for this node as a DebugLoc.
const DebugLoc &getDebugLoc() const { return DbgLoc; }
/// Set or clear the nsw flag on this instruction, which must be an operator
/// which supports this flag. See LangRef.html for the meaning of this flag.
void setHasNoUnsignedWrap(bool b = true);
/// Set or clear the nsw flag on this instruction, which must be an operator
/// which supports this flag. See LangRef.html for the meaning of this flag.
void setHasNoSignedWrap(bool b = true);
/// Set or clear the exact flag on this instruction, which must be an operator
/// which supports this flag. See LangRef.html for the meaning of this flag.
void setIsExact(bool b = true);
/// Determine whether the no unsigned wrap flag is set.
bool hasNoUnsignedWrap() const;
/// Determine whether the no signed wrap flag is set.
bool hasNoSignedWrap() const;
/// Drops flags that may cause this instruction to evaluate to poison despite
/// having non-poison inputs.
void dropPoisonGeneratingFlags();
/// Determine whether the exact flag is set.
bool isExact() const;
/// Set or clear the unsafe-algebra flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of
/// this flag.
void setHasUnsafeAlgebra(bool B);
/// Set or clear the no-nans flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of
/// this flag.
void setHasNoNaNs(bool B);
/// Set or clear the no-infs flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of
/// this flag.
void setHasNoInfs(bool B);
/// Set or clear the no-signed-zeros flag on this instruction, which must be
/// an operator which supports this flag. See LangRef.html for the meaning of
/// this flag.
void setHasNoSignedZeros(bool B);
/// Set or clear the allow-reciprocal flag on this instruction, which must be
/// an operator which supports this flag. See LangRef.html for the meaning of
/// this flag.
void setHasAllowReciprocal(bool B);
/// Convenience function for setting multiple fast-math flags on this
/// instruction, which must be an operator which supports these flags. See
/// LangRef.html for the meaning of these flags.
void setFastMathFlags(FastMathFlags FMF);
/// Convenience function for transferring all fast-math flag values to this
/// instruction, which must be an operator which supports these flags. See
/// LangRef.html for the meaning of these flags.
void copyFastMathFlags(FastMathFlags FMF);
/// Determine whether the unsafe-algebra flag is set.
bool hasUnsafeAlgebra() const;
/// Determine whether the no-NaNs flag is set.
bool hasNoNaNs() const;
/// Determine whether the no-infs flag is set.
bool hasNoInfs() const;
/// Determine whether the no-signed-zeros flag is set.
bool hasNoSignedZeros() const;
/// Determine whether the allow-reciprocal flag is set.
bool hasAllowReciprocal() const;
/// Determine whether the allow-contract flag is set.
bool hasAllowContract() const;
/// Convenience function for getting all the fast-math flags, which must be an
/// operator which supports these flags. See LangRef.html for the meaning of
/// these flags.
FastMathFlags getFastMathFlags() const;
/// Copy I's fast-math flags
void copyFastMathFlags(const Instruction *I);
/// Convenience method to copy supported exact, fast-math, and (optionally)
/// wrapping flags from V to this instruction.
void copyIRFlags(const Value *V, bool IncludeWrapFlags = true);
/// Logical 'and' of any supported wrapping, exact, and fast-math flags of
/// V and this instruction.
void andIRFlags(const Value *V);
private:
/// Return true if we have an entry in the on-the-side metadata hash.
bool hasMetadataHashEntry() const {
return (getSubclassDataFromValue() & HasMetadataBit) != 0;
}
// These are all implemented in Metadata.cpp.
MDNode *getMetadataImpl(unsigned KindID) const;
MDNode *getMetadataImpl(StringRef Kind) const;
void
getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
void getAllMetadataOtherThanDebugLocImpl(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
/// Clear all hashtable-based metadata from this instruction.
void clearMetadataHashEntries();
public:
//===--------------------------------------------------------------------===//
// Predicates and helper methods.
//===--------------------------------------------------------------------===//
/// Return true if the instruction is associative:
///
/// Associative operators satisfy: x op (y op z) === (x op y) op z
///
/// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
///
bool isAssociative() const LLVM_READONLY;
static bool isAssociative(unsigned Opcode) {
return Opcode == And || Opcode == Or || Opcode == Xor ||
Opcode == Add || Opcode == Mul;
}
/// Return true if the instruction is commutative:
///
/// Commutative operators satisfy: (x op y) === (y op x)
///
/// In LLVM, these are the commutative operators, plus SetEQ and SetNE, when
/// applied to any type.
///
bool isCommutative() const { return isCommutative(getOpcode()); }
static bool isCommutative(unsigned Opcode) {
switch (Opcode) {
case Add: case FAdd:
case Mul: case FMul:
case And: case Or: case Xor:
return true;
default:
return false;
}
}
/// Return true if the instruction is idempotent:
///
/// Idempotent operators satisfy: x op x === x
///
/// In LLVM, the And and Or operators are idempotent.
///
bool isIdempotent() const { return isIdempotent(getOpcode()); }
static bool isIdempotent(unsigned Opcode) {
return Opcode == And || Opcode == Or;
}
/// Return true if the instruction is nilpotent:
///
/// Nilpotent operators satisfy: x op x === Id,
///
/// where Id is the identity for the operator, i.e. a constant such that
/// x op Id === x and Id op x === x for all x.
///
/// In LLVM, the Xor operator is nilpotent.
///
bool isNilpotent() const { return isNilpotent(getOpcode()); }
static bool isNilpotent(unsigned Opcode) {
return Opcode == Xor;
}
/// Return true if this instruction may modify memory.
bool mayWriteToMemory() const;
/// Return true if this instruction may read memory.
bool mayReadFromMemory() const;
/// Return true if this instruction may read or write memory.
bool mayReadOrWriteMemory() const {
return mayReadFromMemory() || mayWriteToMemory();
}
/// Return true if this instruction has an AtomicOrdering of unordered or
/// higher.
bool isAtomic() const;
/// Return true if this atomic instruction loads from memory.
bool hasAtomicLoad() const;
/// Return true if this atomic instruction stores to memory.
bool hasAtomicStore() const;
/// Return true if this instruction may throw an exception.
bool mayThrow() const;
/// Return true if this instruction behaves like a memory fence: it can load
/// or store to memory location without being given a memory location.
bool isFenceLike() const {
switch (getOpcode()) {
default:
return false;
// This list should be kept in sync with the list in mayWriteToMemory for
// all opcodes which don't have a memory location.
case Instruction::Fence:
case Instruction::CatchPad:
case Instruction::CatchRet:
case Instruction::Call:
case Instruction::Invoke:
return true;
}
}
/// Return true if the instruction may have side effects.
///
/// Note that this does not consider malloc and alloca to have side
/// effects because the newly allocated memory is completely invisible to
/// instructions which don't use the returned value. For cases where this
/// matters, isSafeToSpeculativelyExecute may be more appropriate.
bool mayHaveSideEffects() const { return mayWriteToMemory() || mayThrow(); }
/// Return true if the instruction is a variety of EH-block.
bool isEHPad() const {
switch (getOpcode()) {
case Instruction::CatchSwitch:
case Instruction::CatchPad:
case Instruction::CleanupPad:
case Instruction::LandingPad:
return true;
default:
return false;
}
}
/// Create a copy of 'this' instruction that is identical in all ways except
/// the following:
/// * The instruction has no parent
/// * The instruction has no name
///
Instruction *clone() const;
/// Return true if the specified instruction is exactly identical to the
/// current one. This means that all operands match and any extra information
/// (e.g. load is volatile) agree.
bool isIdenticalTo(const Instruction *I) const;
/// This is like isIdenticalTo, except that it ignores the
/// SubclassOptionalData flags, which may specify conditions under which the
/// instruction's result is undefined.
bool isIdenticalToWhenDefined(const Instruction *I) const;
/// When checking for operation equivalence (using isSameOperationAs) it is
/// sometimes useful to ignore certain attributes.
enum OperationEquivalenceFlags {
/// Check for equivalence ignoring load/store alignment.
CompareIgnoringAlignment = 1<<0,
/// Check for equivalence treating a type and a vector of that type
/// as equivalent.
CompareUsingScalarTypes = 1<<1
};
/// This function determines if the specified instruction executes the same
/// operation as the current one. This means that the opcodes, type, operand
/// types and any other factors affecting the operation must be the same. This
/// is similar to isIdenticalTo except the operands themselves don't have to
/// be identical.
/// @returns true if the specified instruction is the same operation as
/// the current one.
/// @brief Determine if one instruction is the same operation as another.
bool isSameOperationAs(const Instruction *I, unsigned flags = 0) const;
/// Return true if there are any uses of this instruction in blocks other than
/// the specified block. Note that PHI nodes are considered to evaluate their
/// operands in the corresponding predecessor block.
bool isUsedOutsideOfBlock(const BasicBlock *BB) const;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Value *V) {
return V->getValueID() >= Value::InstructionVal;
}
//----------------------------------------------------------------------
// Exported enumerations.
//
enum TermOps { // These terminate basic blocks
#define FIRST_TERM_INST(N) TermOpsBegin = N,
#define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
#define LAST_TERM_INST(N) TermOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
enum BinaryOps {
#define FIRST_BINARY_INST(N) BinaryOpsBegin = N,
#define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
#define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
enum MemoryOps {
#define FIRST_MEMORY_INST(N) MemoryOpsBegin = N,
#define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
#define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
enum CastOps {
#define FIRST_CAST_INST(N) CastOpsBegin = N,
#define HANDLE_CAST_INST(N, OPC, CLASS) OPC = N,
#define LAST_CAST_INST(N) CastOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
enum FuncletPadOps {
#define FIRST_FUNCLETPAD_INST(N) FuncletPadOpsBegin = N,
#define HANDLE_FUNCLETPAD_INST(N, OPC, CLASS) OPC = N,
#define LAST_FUNCLETPAD_INST(N) FuncletPadOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
enum OtherOps {
#define FIRST_OTHER_INST(N) OtherOpsBegin = N,
#define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N,
#define LAST_OTHER_INST(N) OtherOpsEnd = N+1
#include "llvm/IR/Instruction.def"
};
private:
friend class SymbolTableListTraits<Instruction>;
// Shadow Value::setValueSubclassData with a private forwarding method so that
// subclasses cannot accidentally use it.
void setValueSubclassData(unsigned short D) {
Value::setValueSubclassData(D);
}
unsigned short getSubclassDataFromValue() const {
return Value::getSubclassDataFromValue();
}
void setHasMetadataHashEntry(bool V) {
setValueSubclassData((getSubclassDataFromValue() & ~HasMetadataBit) |
(V ? HasMetadataBit : 0));
}
void setParent(BasicBlock *P);
protected:
// Instruction subclasses can stick up to 15 bits of stuff into the
// SubclassData field of instruction with these members.
// Verify that only the low 15 bits are used.
void setInstructionSubclassData(unsigned short D) {
assert((D & HasMetadataBit) == 0 && "Out of range value put into field");
setValueSubclassData((getSubclassDataFromValue() & HasMetadataBit) | D);
}
unsigned getSubclassDataFromInstruction() const {
return getSubclassDataFromValue() & ~HasMetadataBit;
}
Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
Instruction *InsertBefore = nullptr);
Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
BasicBlock *InsertAtEnd);
private:
/// Create a copy of this instruction.
Instruction *cloneImpl() const;
};
inline void ilist_alloc_traits<Instruction>::deleteNode(Instruction *V) {
V->deleteValue();
}
} // end namespace llvm
#endif // LLVM_IR_INSTRUCTION_H