//===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+// 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
#define LLVM_INSTRUCTION_H
#include "llvm/User.h"
-#include "Support/Annotation.h"
+#include "llvm/ADT/ilist_node.h"
+#include "llvm/Support/DebugLoc.h"
namespace llvm {
-class AssemblyAnnotationWriter;
+class LLVMContext;
+class MDNode;
-template<typename SC> struct ilist_traits;
-template<typename ValueSubClass, typename ItemParentClass, typename SymTabClass,
- typename SubClass> class SymbolTableListTraits;
+template<typename ValueSubClass, typename ItemParentClass>
+ class SymbolTableListTraits;
+
+class Instruction : public User, public ilist_node<Instruction> {
+ void operator=(const Instruction &); // Do not implement
+ Instruction(const Instruction &); // Do not implement
-class Instruction : public User, public Annotable {
BasicBlock *Parent;
- Instruction *Prev, *Next; // Next and Prev links for our intrusive linked list
+ DebugLoc DbgLoc; // 'dbg' Metadata cache.
+
+ enum {
+ /// HasMetadataBit - This is a bit stored in the SubClassData field which
+ /// indicates whether this instruction has metadata attached to it or not.
+ HasMetadataBit = 1 << 15
+ };
+public:
+ // Out of line virtual method, so the vtable, etc has a home.
+ ~Instruction();
+
+ /// use_back - Specialize the methods defined in Value, as we know that an
+ /// instruction can only be used by other instructions.
+ Instruction *use_back() { return cast<Instruction>(*use_begin());}
+ const Instruction *use_back() const { return cast<Instruction>(*use_begin());}
+
+ inline const BasicBlock *getParent() const { return Parent; }
+ inline BasicBlock *getParent() { return Parent; }
- void setNext(Instruction *N) { Next = N; }
- void setPrev(Instruction *N) { Prev = N; }
+ /// removeFromParent - This method unlinks 'this' from the containing basic
+ /// block, but does not delete it.
+ ///
+ void removeFromParent();
- friend class SymbolTableListTraits<Instruction, BasicBlock, Function,
- ilist_traits<Instruction> >;
- void setParent(BasicBlock *P);
- void init();
+ /// eraseFromParent - This method unlinks 'this' from the containing basic
+ /// block and deletes it.
+ ///
+ void eraseFromParent();
-protected:
- unsigned iType; // InstructionType: The opcode of the instruction
+ /// insertBefore - Insert an unlinked instructions into a basic block
+ /// immediately before the specified instruction.
+ void insertBefore(Instruction *InsertPos);
- Instruction(const Type *Ty, unsigned iType, const std::string &Name = "",
- Instruction *InsertBefore = 0);
- Instruction(const Type *Ty, unsigned iType, const std::string &Name,
- BasicBlock *InsertAtEnd);
-public:
+ /// insertAfter - Insert an unlinked instructions into a basic block
+ /// immediately after the specified instruction.
+ void insertAfter(Instruction *InsertPos);
- ~Instruction() {
- assert(Parent == 0 && "Instruction still linked in the program!");
- }
+ /// moveBefore - 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);
- // Specialize setName to handle symbol table majik...
- virtual void setName(const std::string &name, SymbolTable *ST = 0);
+ //===--------------------------------------------------------------------===//
+ // Subclass classification.
+ //===--------------------------------------------------------------------===//
- /// clone() - 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
- ///
- virtual Instruction *clone() const = 0;
+ /// getOpcode() returns a member of one of the enums like Instruction::Add.
+ unsigned getOpcode() const { return getValueID() - InstructionVal; }
- // Accessor methods...
- //
- inline const BasicBlock *getParent() const { return Parent; }
- inline BasicBlock *getParent() { return Parent; }
+ 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()); }
+
+ static const char* getOpcodeName(unsigned OpCode);
- // getNext/Prev - Return the next or previous instruction in the list. The
- // last node in the list is a terminator instruction.
- Instruction *getNext() { return Next; }
- const Instruction *getNext() const { return Next; }
- Instruction *getPrev() { return Prev; }
- const Instruction *getPrev() const { return Prev; }
+ static inline bool isTerminator(unsigned OpCode) {
+ return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
+ }
- /// mayWriteToMemory - Return true if this instruction may modify memory.
- ///
- virtual bool mayWriteToMemory() const { return false; }
+ static inline bool isBinaryOp(unsigned Opcode) {
+ return Opcode >= BinaryOpsBegin && Opcode < BinaryOpsEnd;
+ }
- // ---------------------------------------------------------------------------
- /// Subclass classification... getOpcode() returns a member of
- /// one of the enums that is coming soon (down below)...
- ///
- unsigned getOpcode() const { return iType; }
- virtual const char *getOpcodeName() const {
- return getOpcodeName(getOpcode());
+ /// @brief Determine if the Opcode is one of the shift instructions.
+ static inline bool isShift(unsigned Opcode) {
+ return Opcode >= Shl && Opcode <= AShr;
+ }
+
+ /// isLogicalShift - Return true if this is a logical shift left or a logical
+ /// shift right.
+ inline bool isLogicalShift() const {
+ return getOpcode() == Shl || getOpcode() == LShr;
}
- static const char* getOpcodeName(unsigned OpCode);
- inline bool isTerminator() const { // Instance of TerminatorInst?
- return iType >= TermOpsBegin && iType < TermOpsEnd;
+ /// isArithmeticShift - Return true if this is an arithmetic shift right.
+ inline bool isArithmeticShift() const {
+ return getOpcode() == AShr;
}
- inline bool isBinaryOp() const {
- return iType >= BinaryOpsBegin && iType < BinaryOpsEnd;
+
+ /// @brief Determine if the OpCode is one of the CastInst instructions.
+ static inline bool isCast(unsigned OpCode) {
+ return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
}
+ //===--------------------------------------------------------------------===//
+ // Metadata manipulation.
+ //===--------------------------------------------------------------------===//
+
+ /// hasMetadata() - Return true if this instruction has any metadata attached
+ /// to it.
+ bool hasMetadata() const {
+ return !DbgLoc.isUnknown() || hasMetadataHashEntry();
+ }
+
+ /// hasMetadataOtherThanDebugLoc - Return true if this instruction has
+ /// metadata attached to it other than a debug location.
+ bool hasMetadataOtherThanDebugLoc() const {
+ return hasMetadataHashEntry();
+ }
+
+ /// getMetadata - 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 0;
+ return getMetadataImpl(KindID);
+ }
+
+ /// getMetadata - Get the metadata of given kind attached to this Instruction.
+ /// If the metadata is not found then return null.
+ MDNode *getMetadata(const char *Kind) const {
+ if (!hasMetadata()) return 0;
+ return getMetadataImpl(Kind);
+ }
+
+ /// getAllMetadata - 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);
+ }
+
+ /// getAllMetadataOtherThanDebugLoc - 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);
+ }
+
+ /// setMetadata - Set the metadata of the specified kind to the specified
+ /// node. This updates/replaces metadata if already present, or removes it if
+ /// Node is null.
+ void setMetadata(unsigned KindID, MDNode *Node);
+ void setMetadata(const char *Kind, MDNode *Node);
+
+ /// setDebugLoc - Set the debug location information for this instruction.
+ void setDebugLoc(const DebugLoc &Loc) { DbgLoc = Loc; }
+
+ /// getDebugLoc - Return the debug location for this node as a DebugLoc.
+ const DebugLoc &getDebugLoc() const { return DbgLoc; }
+
+private:
+ /// hasMetadataHashEntry - 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(const char *Kind) const;
+ void getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,MDNode*> > &)const;
+ void getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,
+ MDNode*> > &) const;
+ void clearMetadataHashEntries();
+public:
+ //===--------------------------------------------------------------------===//
+ // Predicates and helper methods.
+ //===--------------------------------------------------------------------===//
+
+
/// isAssociative - Return true if the instruction is associative:
///
/// Associative operators satisfy: x op (y op z) === (x op y) op z
bool isCommutative() const { return isCommutative(getOpcode()); }
static bool isCommutative(unsigned op);
- /// isRelational - Return true if the instruction is a Set* instruction:
+ /// mayWriteToMemory - Return true if this instruction may modify memory.
+ ///
+ bool mayWriteToMemory() const;
+
+ /// mayReadFromMemory - Return true if this instruction may read memory.
///
- bool isRelational() const { return isRelational(getOpcode()); }
- static bool isRelational(unsigned op);
+ bool mayReadFromMemory() const;
+ /// mayThrow - Return true if this instruction may throw an exception.
+ ///
+ bool mayThrow() const;
- /// isTrappingInstruction - Return true if the instruction may trap.
+ /// mayHaveSideEffects - Return true if the instruction may have side effects.
///
- bool isTrapping() const {
- return isTrapping(getOpcode());
+ /// 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 used the returned value. For cases where this
+ /// matters, isSafeToSpeculativelyExecute may be more appropriate.
+ bool mayHaveSideEffects() const {
+ return mayWriteToMemory() || mayThrow();
}
- static bool isTrapping(unsigned op);
-
- virtual void print(std::ostream &OS) const { print(OS, 0); }
- void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) const;
+ /// isSafeToSpeculativelyExecute - Return true if the instruction does not
+ /// have any effects besides calculating the result and does not have
+ /// undefined behavior.
+ ///
+ /// This method never returns true for an instruction that returns true for
+ /// mayHaveSideEffects; however, this method also does some other checks in
+ /// addition. It checks for undefined behavior, like dividing by zero or
+ /// loading from an invalid pointer (but not for undefined results, like a
+ /// shift with a shift amount larger than the width of the result). It checks
+ /// for malloc and alloca because speculatively executing them might cause a
+ /// memory leak. It also returns false for instructions related to control
+ /// flow, specifically terminators and PHI nodes.
+ ///
+ /// This method only looks at the instruction itself and its operands, so if
+ /// this method returns true, it is safe to move the instruction as long as
+ /// the correct dominance relationships for the operands and users hold.
+ /// However, this method can return true for instructions that read memory;
+ /// for such instructions, moving them may change the resulting value.
+ bool isSafeToSpeculativelyExecute() const;
+
+ /// clone() - 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;
+
+ /// isIdenticalTo - 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;
+
+ /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it
+ /// ignores the SubclassOptionalData flags, which specify conditions
+ /// under which the instruction's result is undefined.
+ bool isIdenticalToWhenDefined(const Instruction *I) const;
+
+ /// 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) const;
+
+ /// isUsedOutsideOfBlock - 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 Instruction *I) { return true; }
+ static inline bool classof(const Instruction *) { return true; }
static inline bool classof(const Value *V) {
- return V->getValueType() == Value::InstructionVal;
+ return V->getValueID() >= Value::InstructionVal;
}
-
+
//----------------------------------------------------------------------
- // Exported enumerations...
+ // 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,
+#define LAST_TERM_INST(N) TermOpsEnd = N+1
#include "llvm/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,
+#define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
#include "llvm/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,
+#define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
+#include "llvm/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/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,
+#define LAST_OTHER_INST(N) OtherOpsEnd = N+1
#include "llvm/Instruction.def"
};
+private:
+ // 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));
+ }
+
+ friend class SymbolTableListTraits<Instruction, BasicBlock>;
+ 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(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
+ Instruction *InsertBefore = 0);
+ Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
+ BasicBlock *InsertAtEnd);
+ virtual Instruction *clone_impl() const = 0;
+
};
+// Instruction* is only 4-byte aligned.
+template<>
+class PointerLikeTypeTraits<Instruction*> {
+ typedef Instruction* PT;
+public:
+ static inline void *getAsVoidPointer(PT P) { return P; }
+ static inline PT getFromVoidPointer(void *P) {
+ return static_cast<PT>(P);
+ }
+ enum { NumLowBitsAvailable = 2 };
+};
+
} // End llvm namespace
#endif