1 //===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the declaration of the Instruction class, which is the
11 // base class for all of the LLVM instructions.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_IR_INSTRUCTION_H
16 #define LLVM_IR_INSTRUCTION_H
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/ilist_node.h"
20 #include "llvm/IR/DebugLoc.h"
21 #include "llvm/IR/SymbolTableListTraits.h"
22 #include "llvm/IR/User.h"
33 struct SymbolTableListSentinelTraits<Instruction>
34 : public ilist_half_embedded_sentinel_traits<Instruction> {};
36 class Instruction : public User,
37 public ilist_node_with_parent<Instruction, BasicBlock> {
38 void operator=(const Instruction &) = delete;
39 Instruction(const Instruction &) = delete;
42 DebugLoc DbgLoc; // 'dbg' Metadata cache.
45 /// HasMetadataBit - This is a bit stored in the SubClassData field which
46 /// indicates whether this instruction has metadata attached to it or not.
47 HasMetadataBit = 1 << 15
50 // Out of line virtual method, so the vtable, etc has a home.
51 ~Instruction() override;
53 /// user_back - Specialize the methods defined in Value, as we know that an
54 /// instruction can only be used by other instructions.
55 Instruction *user_back() { return cast<Instruction>(*user_begin());}
56 const Instruction *user_back() const { return cast<Instruction>(*user_begin());}
58 inline const BasicBlock *getParent() const { return Parent; }
59 inline BasicBlock *getParent() { return Parent; }
61 /// \brief Return the module owning the function this instruction belongs to
62 /// or nullptr it the function does not have a module.
64 /// Note: this is undefined behavior if the instruction does not have a
65 /// parent, or the parent basic block does not have a parent function.
66 const Module *getModule() const;
69 /// \brief Return the function this instruction belongs to.
71 /// Note: it is undefined behavior to call this on an instruction not
72 /// currently inserted into a function.
73 const Function *getFunction() const;
74 Function *getFunction();
76 /// removeFromParent - This method unlinks 'this' from the containing basic
77 /// block, but does not delete it.
79 void removeFromParent();
81 /// eraseFromParent - This method unlinks 'this' from the containing basic
82 /// block and deletes it.
84 /// \returns an iterator pointing to the element after the erased one
85 SymbolTableList<Instruction>::iterator eraseFromParent();
87 /// Insert an unlinked instruction into a basic block immediately before
88 /// the specified instruction.
89 void insertBefore(Instruction *InsertPos);
91 /// Insert an unlinked instruction into a basic block immediately after the
92 /// specified instruction.
93 void insertAfter(Instruction *InsertPos);
95 /// moveBefore - Unlink this instruction from its current basic block and
96 /// insert it into the basic block that MovePos lives in, right before
98 void moveBefore(Instruction *MovePos);
100 //===--------------------------------------------------------------------===//
101 // Subclass classification.
102 //===--------------------------------------------------------------------===//
104 /// getOpcode() returns a member of one of the enums like Instruction::Add.
105 unsigned getOpcode() const { return getValueID() - InstructionVal; }
107 const char *getOpcodeName() const { return getOpcodeName(getOpcode()); }
108 bool isTerminator() const { return isTerminator(getOpcode()); }
109 bool isBinaryOp() const { return isBinaryOp(getOpcode()); }
110 bool isShift() { return isShift(getOpcode()); }
111 bool isCast() const { return isCast(getOpcode()); }
112 bool isFuncletPad() const { return isFuncletPad(getOpcode()); }
114 static const char* getOpcodeName(unsigned OpCode);
116 static inline bool isTerminator(unsigned OpCode) {
117 return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
120 static inline bool isBinaryOp(unsigned Opcode) {
121 return Opcode >= BinaryOpsBegin && Opcode < BinaryOpsEnd;
124 /// @brief Determine if the Opcode is one of the shift instructions.
125 static inline bool isShift(unsigned Opcode) {
126 return Opcode >= Shl && Opcode <= AShr;
129 /// isLogicalShift - Return true if this is a logical shift left or a logical
131 inline bool isLogicalShift() const {
132 return getOpcode() == Shl || getOpcode() == LShr;
135 /// isArithmeticShift - Return true if this is an arithmetic shift right.
136 inline bool isArithmeticShift() const {
137 return getOpcode() == AShr;
140 /// @brief Determine if the OpCode is one of the CastInst instructions.
141 static inline bool isCast(unsigned OpCode) {
142 return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
145 /// @brief Determine if the OpCode is one of the FuncletPadInst instructions.
146 static inline bool isFuncletPad(unsigned OpCode) {
147 return OpCode >= FuncletPadOpsBegin && OpCode < FuncletPadOpsEnd;
150 //===--------------------------------------------------------------------===//
151 // Metadata manipulation.
152 //===--------------------------------------------------------------------===//
154 /// hasMetadata() - Return true if this instruction has any metadata attached
156 bool hasMetadata() const { return DbgLoc || hasMetadataHashEntry(); }
158 /// hasMetadataOtherThanDebugLoc - Return true if this instruction has
159 /// metadata attached to it other than a debug location.
160 bool hasMetadataOtherThanDebugLoc() const {
161 return hasMetadataHashEntry();
164 /// getMetadata - Get the metadata of given kind attached to this Instruction.
165 /// If the metadata is not found then return null.
166 MDNode *getMetadata(unsigned KindID) const {
167 if (!hasMetadata()) return nullptr;
168 return getMetadataImpl(KindID);
171 /// getMetadata - Get the metadata of given kind attached to this Instruction.
172 /// If the metadata is not found then return null.
173 MDNode *getMetadata(StringRef Kind) const {
174 if (!hasMetadata()) return nullptr;
175 return getMetadataImpl(Kind);
178 /// getAllMetadata - Get all metadata attached to this Instruction. The first
179 /// element of each pair returned is the KindID, the second element is the
180 /// metadata value. This list is returned sorted by the KindID.
182 getAllMetadata(SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
184 getAllMetadataImpl(MDs);
187 /// getAllMetadataOtherThanDebugLoc - This does the same thing as
188 /// getAllMetadata, except that it filters out the debug location.
189 void getAllMetadataOtherThanDebugLoc(
190 SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
191 if (hasMetadataOtherThanDebugLoc())
192 getAllMetadataOtherThanDebugLocImpl(MDs);
195 /// getAAMetadata - Fills the AAMDNodes structure with AA metadata from
196 /// this instruction. When Merge is true, the existing AA metadata is
197 /// merged with that from this instruction providing the most-general result.
198 void getAAMetadata(AAMDNodes &N, bool Merge = false) const;
200 /// setMetadata - Set the metadata of the specified kind to the specified
201 /// node. This updates/replaces metadata if already present, or removes it if
203 void setMetadata(unsigned KindID, MDNode *Node);
204 void setMetadata(StringRef Kind, MDNode *Node);
206 /// Drop all unknown metadata except for debug locations.
208 /// Passes are required to drop metadata they don't understand. This is a
209 /// convenience method for passes to do so.
210 void dropUnknownNonDebugMetadata(ArrayRef<unsigned> KnownIDs);
211 void dropUnknownNonDebugMetadata() {
212 return dropUnknownNonDebugMetadata(None);
214 void dropUnknownNonDebugMetadata(unsigned ID1) {
215 return dropUnknownNonDebugMetadata(makeArrayRef(ID1));
217 void dropUnknownNonDebugMetadata(unsigned ID1, unsigned ID2) {
218 unsigned IDs[] = {ID1, ID2};
219 return dropUnknownNonDebugMetadata(IDs);
223 /// setAAMetadata - Sets the metadata on this instruction from the
224 /// AAMDNodes structure.
225 void setAAMetadata(const AAMDNodes &N);
227 /// setDebugLoc - Set the debug location information for this instruction.
228 void setDebugLoc(DebugLoc Loc) { DbgLoc = std::move(Loc); }
230 /// getDebugLoc - Return the debug location for this node as a DebugLoc.
231 const DebugLoc &getDebugLoc() const { return DbgLoc; }
233 /// Set or clear the unsafe-algebra flag on this instruction, which must be an
234 /// operator which supports this flag. See LangRef.html for the meaning of
236 void setHasUnsafeAlgebra(bool B);
238 /// Set or clear the no-nans flag on this instruction, which must be an
239 /// operator which supports this flag. See LangRef.html for the meaning of
241 void setHasNoNaNs(bool B);
243 /// Set or clear the no-infs flag on this instruction, which must be an
244 /// operator which supports this flag. See LangRef.html for the meaning of
246 void setHasNoInfs(bool B);
248 /// Set or clear the no-signed-zeros flag on this instruction, which must be
249 /// an operator which supports this flag. See LangRef.html for the meaning of
251 void setHasNoSignedZeros(bool B);
253 /// Set or clear the allow-reciprocal flag on this instruction, which must be
254 /// an operator which supports this flag. See LangRef.html for the meaning of
256 void setHasAllowReciprocal(bool B);
258 /// Convenience function for setting multiple fast-math flags on this
259 /// instruction, which must be an operator which supports these flags. See
260 /// LangRef.html for the meaning of these flags.
261 void setFastMathFlags(FastMathFlags FMF);
263 /// Convenience function for transferring all fast-math flag values to this
264 /// instruction, which must be an operator which supports these flags. See
265 /// LangRef.html for the meaning of these flags.
266 void copyFastMathFlags(FastMathFlags FMF);
268 /// Determine whether the unsafe-algebra flag is set.
269 bool hasUnsafeAlgebra() const;
271 /// Determine whether the no-NaNs flag is set.
272 bool hasNoNaNs() const;
274 /// Determine whether the no-infs flag is set.
275 bool hasNoInfs() const;
277 /// Determine whether the no-signed-zeros flag is set.
278 bool hasNoSignedZeros() const;
280 /// Determine whether the allow-reciprocal flag is set.
281 bool hasAllowReciprocal() const;
283 /// Convenience function for getting all the fast-math flags, which must be an
284 /// operator which supports these flags. See LangRef.html for the meaning of
286 FastMathFlags getFastMathFlags() const;
288 /// Copy I's fast-math flags
289 void copyFastMathFlags(const Instruction *I);
292 /// hasMetadataHashEntry - Return true if we have an entry in the on-the-side
294 bool hasMetadataHashEntry() const {
295 return (getSubclassDataFromValue() & HasMetadataBit) != 0;
298 // These are all implemented in Metadata.cpp.
299 MDNode *getMetadataImpl(unsigned KindID) const;
300 MDNode *getMetadataImpl(StringRef Kind) const;
302 getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
303 void getAllMetadataOtherThanDebugLocImpl(
304 SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
305 void clearMetadataHashEntries();
307 //===--------------------------------------------------------------------===//
308 // Predicates and helper methods.
309 //===--------------------------------------------------------------------===//
312 /// isAssociative - Return true if the instruction is associative:
314 /// Associative operators satisfy: x op (y op z) === (x op y) op z
316 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
318 bool isAssociative() const;
319 static bool isAssociative(unsigned op);
321 /// isCommutative - Return true if the instruction is commutative:
323 /// Commutative operators satisfy: (x op y) === (y op x)
325 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
326 /// applied to any type.
328 bool isCommutative() const { return isCommutative(getOpcode()); }
329 static bool isCommutative(unsigned op);
331 /// isIdempotent - Return true if the instruction is idempotent:
333 /// Idempotent operators satisfy: x op x === x
335 /// In LLVM, the And and Or operators are idempotent.
337 bool isIdempotent() const { return isIdempotent(getOpcode()); }
338 static bool isIdempotent(unsigned op);
340 /// isNilpotent - Return true if the instruction is nilpotent:
342 /// Nilpotent operators satisfy: x op x === Id,
344 /// where Id is the identity for the operator, i.e. a constant such that
345 /// x op Id === x and Id op x === x for all x.
347 /// In LLVM, the Xor operator is nilpotent.
349 bool isNilpotent() const { return isNilpotent(getOpcode()); }
350 static bool isNilpotent(unsigned op);
352 /// mayWriteToMemory - Return true if this instruction may modify memory.
354 bool mayWriteToMemory() const;
356 /// mayReadFromMemory - Return true if this instruction may read memory.
358 bool mayReadFromMemory() const;
360 /// mayReadOrWriteMemory - Return true if this instruction may read or
363 bool mayReadOrWriteMemory() const {
364 return mayReadFromMemory() || mayWriteToMemory();
367 /// isAtomic - Return true if this instruction has an
368 /// AtomicOrdering of unordered or higher.
370 bool isAtomic() const;
372 /// mayThrow - Return true if this instruction may throw an exception.
374 bool mayThrow() const;
376 /// mayReturn - Return true if this is a function that may return.
377 /// this is true for all normal instructions. The only exception
378 /// is functions that are marked with the 'noreturn' attribute.
380 bool mayReturn() const;
382 /// mayHaveSideEffects - Return true if the instruction may have side effects.
384 /// Note that this does not consider malloc and alloca to have side
385 /// effects because the newly allocated memory is completely invisible to
386 /// instructions which don't use the returned value. For cases where this
387 /// matters, isSafeToSpeculativelyExecute may be more appropriate.
388 bool mayHaveSideEffects() const {
389 return mayWriteToMemory() || mayThrow() || !mayReturn();
392 /// \brief Return true if the instruction is a variety of EH-block.
393 bool isEHPad() const {
394 switch (getOpcode()) {
395 case Instruction::CatchSwitch:
396 case Instruction::CatchPad:
397 case Instruction::CleanupPad:
398 case Instruction::LandingPad:
405 /// clone() - Create a copy of 'this' instruction that is identical in all
406 /// ways except the following:
407 /// * The instruction has no parent
408 /// * The instruction has no name
410 Instruction *clone() const;
412 /// isIdenticalTo - Return true if the specified instruction is exactly
413 /// identical to the current one. This means that all operands match and any
414 /// extra information (e.g. load is volatile) agree.
415 bool isIdenticalTo(const Instruction *I) const;
417 /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it
418 /// ignores the SubclassOptionalData flags, which specify conditions
419 /// under which the instruction's result is undefined.
420 bool isIdenticalToWhenDefined(const Instruction *I) const;
422 /// When checking for operation equivalence (using isSameOperationAs) it is
423 /// sometimes useful to ignore certain attributes.
424 enum OperationEquivalenceFlags {
425 /// Check for equivalence ignoring load/store alignment.
426 CompareIgnoringAlignment = 1<<0,
427 /// Check for equivalence treating a type and a vector of that type
429 CompareUsingScalarTypes = 1<<1
432 /// This function determines if the specified instruction executes the same
433 /// operation as the current one. This means that the opcodes, type, operand
434 /// types and any other factors affecting the operation must be the same. This
435 /// is similar to isIdenticalTo except the operands themselves don't have to
437 /// @returns true if the specified instruction is the same operation as
439 /// @brief Determine if one instruction is the same operation as another.
440 bool isSameOperationAs(const Instruction *I, unsigned flags = 0) const;
442 /// isUsedOutsideOfBlock - Return true if there are any uses of this
443 /// instruction in blocks other than the specified block. Note that PHI nodes
444 /// are considered to evaluate their operands in the corresponding predecessor
446 bool isUsedOutsideOfBlock(const BasicBlock *BB) const;
449 /// Methods for support type inquiry through isa, cast, and dyn_cast:
450 static inline bool classof(const Value *V) {
451 return V->getValueID() >= Value::InstructionVal;
454 //----------------------------------------------------------------------
455 // Exported enumerations.
457 enum TermOps { // These terminate basic blocks
458 #define FIRST_TERM_INST(N) TermOpsBegin = N,
459 #define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
460 #define LAST_TERM_INST(N) TermOpsEnd = N+1
461 #include "llvm/IR/Instruction.def"
465 #define FIRST_BINARY_INST(N) BinaryOpsBegin = N,
466 #define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
467 #define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
468 #include "llvm/IR/Instruction.def"
472 #define FIRST_MEMORY_INST(N) MemoryOpsBegin = N,
473 #define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
474 #define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
475 #include "llvm/IR/Instruction.def"
479 #define FIRST_CAST_INST(N) CastOpsBegin = N,
480 #define HANDLE_CAST_INST(N, OPC, CLASS) OPC = N,
481 #define LAST_CAST_INST(N) CastOpsEnd = N+1
482 #include "llvm/IR/Instruction.def"
486 #define FIRST_FUNCLETPAD_INST(N) FuncletPadOpsBegin = N,
487 #define HANDLE_FUNCLETPAD_INST(N, OPC, CLASS) OPC = N,
488 #define LAST_FUNCLETPAD_INST(N) FuncletPadOpsEnd = N+1
489 #include "llvm/IR/Instruction.def"
493 #define FIRST_OTHER_INST(N) OtherOpsBegin = N,
494 #define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N,
495 #define LAST_OTHER_INST(N) OtherOpsEnd = N+1
496 #include "llvm/IR/Instruction.def"
499 // Shadow Value::setValueSubclassData with a private forwarding method so that
500 // subclasses cannot accidentally use it.
501 void setValueSubclassData(unsigned short D) {
502 Value::setValueSubclassData(D);
504 unsigned short getSubclassDataFromValue() const {
505 return Value::getSubclassDataFromValue();
508 void setHasMetadataHashEntry(bool V) {
509 setValueSubclassData((getSubclassDataFromValue() & ~HasMetadataBit) |
510 (V ? HasMetadataBit : 0));
513 friend class SymbolTableListTraits<Instruction>;
514 void setParent(BasicBlock *P);
516 // Instruction subclasses can stick up to 15 bits of stuff into the
517 // SubclassData field of instruction with these members.
519 // Verify that only the low 15 bits are used.
520 void setInstructionSubclassData(unsigned short D) {
521 assert((D & HasMetadataBit) == 0 && "Out of range value put into field");
522 setValueSubclassData((getSubclassDataFromValue() & HasMetadataBit) | D);
525 unsigned getSubclassDataFromInstruction() const {
526 return getSubclassDataFromValue() & ~HasMetadataBit;
529 Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
530 Instruction *InsertBefore = nullptr);
531 Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
532 BasicBlock *InsertAtEnd);
535 /// Create a copy of this instruction.
536 Instruction *cloneImpl() const;
539 // Instruction* is only 4-byte aligned.
541 class PointerLikeTypeTraits<Instruction*> {
542 typedef Instruction* PT;
544 static inline void *getAsVoidPointer(PT P) { return P; }
545 static inline PT getFromVoidPointer(void *P) {
546 return static_cast<PT>(P);
548 enum { NumLowBitsAvailable = 2 };
551 } // End llvm namespace