1 //===-- Instruction.cpp - Implement the Instruction class -----------------===//
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 implements the Instruction class for the IR library.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/IR/Instruction.h"
15 #include "llvm/IR/CallSite.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/Module.h"
19 #include "llvm/IR/Operator.h"
20 #include "llvm/IR/Type.h"
23 Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps,
24 Instruction *InsertBefore)
25 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(nullptr) {
27 // If requested, insert this instruction into a basic block...
29 BasicBlock *BB = InsertBefore->getParent();
30 assert(BB && "Instruction to insert before is not in a basic block!");
31 BB->getInstList().insert(InsertBefore->getIterator(), this);
35 Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps,
36 BasicBlock *InsertAtEnd)
37 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(nullptr) {
39 // append this instruction into the basic block
40 assert(InsertAtEnd && "Basic block to append to may not be NULL!");
41 InsertAtEnd->getInstList().push_back(this);
45 // Out of line virtual method, so the vtable, etc has a home.
46 Instruction::~Instruction() {
47 assert(!Parent && "Instruction still linked in the program!");
48 if (hasMetadataHashEntry())
49 clearMetadataHashEntries();
53 void Instruction::setParent(BasicBlock *P) {
57 const Module *Instruction::getModule() const {
58 return getParent()->getModule();
61 Module *Instruction::getModule() {
62 return getParent()->getModule();
65 Function *Instruction::getFunction() { return getParent()->getParent(); }
67 const Function *Instruction::getFunction() const {
68 return getParent()->getParent();
71 void Instruction::removeFromParent() {
72 getParent()->getInstList().remove(getIterator());
75 iplist<Instruction>::iterator Instruction::eraseFromParent() {
76 return getParent()->getInstList().erase(getIterator());
79 /// Insert an unlinked instruction into a basic block immediately before the
80 /// specified instruction.
81 void Instruction::insertBefore(Instruction *InsertPos) {
82 InsertPos->getParent()->getInstList().insert(InsertPos->getIterator(), this);
85 /// Insert an unlinked instruction into a basic block immediately after the
86 /// specified instruction.
87 void Instruction::insertAfter(Instruction *InsertPos) {
88 InsertPos->getParent()->getInstList().insertAfter(InsertPos->getIterator(),
92 /// Unlink this instruction from its current basic block and insert it into the
93 /// basic block that MovePos lives in, right before MovePos.
94 void Instruction::moveBefore(Instruction *MovePos) {
95 MovePos->getParent()->getInstList().splice(
96 MovePos->getIterator(), getParent()->getInstList(), getIterator());
99 /// Set or clear the unsafe-algebra flag on this instruction, which must be an
100 /// operator which supports this flag. See LangRef.html for the meaning of this
102 void Instruction::setHasUnsafeAlgebra(bool B) {
103 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
104 cast<FPMathOperator>(this)->setHasUnsafeAlgebra(B);
107 /// Set or clear the NoNaNs flag on this instruction, which must be an operator
108 /// which supports this flag. See LangRef.html for the meaning of this flag.
109 void Instruction::setHasNoNaNs(bool B) {
110 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
111 cast<FPMathOperator>(this)->setHasNoNaNs(B);
114 /// Set or clear the no-infs flag on this instruction, which must be an operator
115 /// which supports this flag. See LangRef.html for the meaning of this flag.
116 void Instruction::setHasNoInfs(bool B) {
117 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
118 cast<FPMathOperator>(this)->setHasNoInfs(B);
121 /// Set or clear the no-signed-zeros flag on this instruction, which must be an
122 /// operator which supports this flag. See LangRef.html for the meaning of this
124 void Instruction::setHasNoSignedZeros(bool B) {
125 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
126 cast<FPMathOperator>(this)->setHasNoSignedZeros(B);
129 /// Set or clear the allow-reciprocal flag on this instruction, which must be an
130 /// operator which supports this flag. See LangRef.html for the meaning of this
132 void Instruction::setHasAllowReciprocal(bool B) {
133 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
134 cast<FPMathOperator>(this)->setHasAllowReciprocal(B);
137 /// Convenience function for setting all the fast-math flags on this
138 /// instruction, which must be an operator which supports these flags. See
139 /// LangRef.html for the meaning of these flats.
140 void Instruction::setFastMathFlags(FastMathFlags FMF) {
141 assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
142 cast<FPMathOperator>(this)->setFastMathFlags(FMF);
145 void Instruction::copyFastMathFlags(FastMathFlags FMF) {
146 assert(isa<FPMathOperator>(this) && "copying fast-math flag on invalid op");
147 cast<FPMathOperator>(this)->copyFastMathFlags(FMF);
150 /// Determine whether the unsafe-algebra flag is set.
151 bool Instruction::hasUnsafeAlgebra() const {
152 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
153 return cast<FPMathOperator>(this)->hasUnsafeAlgebra();
156 /// Determine whether the no-NaNs flag is set.
157 bool Instruction::hasNoNaNs() const {
158 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
159 return cast<FPMathOperator>(this)->hasNoNaNs();
162 /// Determine whether the no-infs flag is set.
163 bool Instruction::hasNoInfs() const {
164 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
165 return cast<FPMathOperator>(this)->hasNoInfs();
168 /// Determine whether the no-signed-zeros flag is set.
169 bool Instruction::hasNoSignedZeros() const {
170 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
171 return cast<FPMathOperator>(this)->hasNoSignedZeros();
174 /// Determine whether the allow-reciprocal flag is set.
175 bool Instruction::hasAllowReciprocal() const {
176 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
177 return cast<FPMathOperator>(this)->hasAllowReciprocal();
180 /// Convenience function for getting all the fast-math flags, which must be an
181 /// operator which supports these flags. See LangRef.html for the meaning of
183 FastMathFlags Instruction::getFastMathFlags() const {
184 assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
185 return cast<FPMathOperator>(this)->getFastMathFlags();
188 /// Copy I's fast-math flags
189 void Instruction::copyFastMathFlags(const Instruction *I) {
190 copyFastMathFlags(I->getFastMathFlags());
194 const char *Instruction::getOpcodeName(unsigned OpCode) {
197 case Ret: return "ret";
198 case Br: return "br";
199 case Switch: return "switch";
200 case IndirectBr: return "indirectbr";
201 case Invoke: return "invoke";
202 case Resume: return "resume";
203 case Unreachable: return "unreachable";
204 case CleanupRet: return "cleanupret";
205 case CatchRet: return "catchret";
206 case CatchPad: return "catchpad";
207 case CatchSwitch: return "catchswitch";
209 // Standard binary operators...
210 case Add: return "add";
211 case FAdd: return "fadd";
212 case Sub: return "sub";
213 case FSub: return "fsub";
214 case Mul: return "mul";
215 case FMul: return "fmul";
216 case UDiv: return "udiv";
217 case SDiv: return "sdiv";
218 case FDiv: return "fdiv";
219 case URem: return "urem";
220 case SRem: return "srem";
221 case FRem: return "frem";
223 // Logical operators...
224 case And: return "and";
225 case Or : return "or";
226 case Xor: return "xor";
228 // Memory instructions...
229 case Alloca: return "alloca";
230 case Load: return "load";
231 case Store: return "store";
232 case AtomicCmpXchg: return "cmpxchg";
233 case AtomicRMW: return "atomicrmw";
234 case Fence: return "fence";
235 case GetElementPtr: return "getelementptr";
237 // Convert instructions...
238 case Trunc: return "trunc";
239 case ZExt: return "zext";
240 case SExt: return "sext";
241 case FPTrunc: return "fptrunc";
242 case FPExt: return "fpext";
243 case FPToUI: return "fptoui";
244 case FPToSI: return "fptosi";
245 case UIToFP: return "uitofp";
246 case SIToFP: return "sitofp";
247 case IntToPtr: return "inttoptr";
248 case PtrToInt: return "ptrtoint";
249 case BitCast: return "bitcast";
250 case AddrSpaceCast: return "addrspacecast";
252 // Other instructions...
253 case ICmp: return "icmp";
254 case FCmp: return "fcmp";
255 case PHI: return "phi";
256 case Select: return "select";
257 case Call: return "call";
258 case Shl: return "shl";
259 case LShr: return "lshr";
260 case AShr: return "ashr";
261 case VAArg: return "va_arg";
262 case ExtractElement: return "extractelement";
263 case InsertElement: return "insertelement";
264 case ShuffleVector: return "shufflevector";
265 case ExtractValue: return "extractvalue";
266 case InsertValue: return "insertvalue";
267 case LandingPad: return "landingpad";
268 case CleanupPad: return "cleanuppad";
270 default: return "<Invalid operator> ";
274 /// Return true if both instructions have the same special state
275 /// This must be kept in sync with lib/Transforms/IPO/MergeFunctions.cpp.
276 static bool haveSameSpecialState(const Instruction *I1, const Instruction *I2,
277 bool IgnoreAlignment = false) {
278 assert(I1->getOpcode() == I2->getOpcode() &&
279 "Can not compare special state of different instructions");
281 if (const LoadInst *LI = dyn_cast<LoadInst>(I1))
282 return LI->isVolatile() == cast<LoadInst>(I2)->isVolatile() &&
283 (LI->getAlignment() == cast<LoadInst>(I2)->getAlignment() ||
285 LI->getOrdering() == cast<LoadInst>(I2)->getOrdering() &&
286 LI->getSynchScope() == cast<LoadInst>(I2)->getSynchScope();
287 if (const StoreInst *SI = dyn_cast<StoreInst>(I1))
288 return SI->isVolatile() == cast<StoreInst>(I2)->isVolatile() &&
289 (SI->getAlignment() == cast<StoreInst>(I2)->getAlignment() ||
291 SI->getOrdering() == cast<StoreInst>(I2)->getOrdering() &&
292 SI->getSynchScope() == cast<StoreInst>(I2)->getSynchScope();
293 if (const CmpInst *CI = dyn_cast<CmpInst>(I1))
294 return CI->getPredicate() == cast<CmpInst>(I2)->getPredicate();
295 if (const CallInst *CI = dyn_cast<CallInst>(I1))
296 return CI->isTailCall() == cast<CallInst>(I2)->isTailCall() &&
297 CI->getCallingConv() == cast<CallInst>(I2)->getCallingConv() &&
298 CI->getAttributes() == cast<CallInst>(I2)->getAttributes() &&
299 CI->hasIdenticalOperandBundleSchema(*cast<CallInst>(I2));
300 if (const InvokeInst *CI = dyn_cast<InvokeInst>(I1))
301 return CI->getCallingConv() == cast<InvokeInst>(I2)->getCallingConv() &&
302 CI->getAttributes() == cast<InvokeInst>(I2)->getAttributes() &&
303 CI->hasIdenticalOperandBundleSchema(*cast<InvokeInst>(I2));
304 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(I1))
305 return IVI->getIndices() == cast<InsertValueInst>(I2)->getIndices();
306 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(I1))
307 return EVI->getIndices() == cast<ExtractValueInst>(I2)->getIndices();
308 if (const FenceInst *FI = dyn_cast<FenceInst>(I1))
309 return FI->getOrdering() == cast<FenceInst>(I2)->getOrdering() &&
310 FI->getSynchScope() == cast<FenceInst>(I2)->getSynchScope();
311 if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I1))
312 return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I2)->isVolatile() &&
313 CXI->isWeak() == cast<AtomicCmpXchgInst>(I2)->isWeak() &&
314 CXI->getSuccessOrdering() ==
315 cast<AtomicCmpXchgInst>(I2)->getSuccessOrdering() &&
316 CXI->getFailureOrdering() ==
317 cast<AtomicCmpXchgInst>(I2)->getFailureOrdering() &&
318 CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I2)->getSynchScope();
319 if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I1))
320 return RMWI->getOperation() == cast<AtomicRMWInst>(I2)->getOperation() &&
321 RMWI->isVolatile() == cast<AtomicRMWInst>(I2)->isVolatile() &&
322 RMWI->getOrdering() == cast<AtomicRMWInst>(I2)->getOrdering() &&
323 RMWI->getSynchScope() == cast<AtomicRMWInst>(I2)->getSynchScope();
328 /// isIdenticalTo - Return true if the specified instruction is exactly
329 /// identical to the current one. This means that all operands match and any
330 /// extra information (e.g. load is volatile) agree.
331 bool Instruction::isIdenticalTo(const Instruction *I) const {
332 return isIdenticalToWhenDefined(I) &&
333 SubclassOptionalData == I->SubclassOptionalData;
336 /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it
337 /// ignores the SubclassOptionalData flags, which specify conditions
338 /// under which the instruction's result is undefined.
339 bool Instruction::isIdenticalToWhenDefined(const Instruction *I) const {
340 if (getOpcode() != I->getOpcode() ||
341 getNumOperands() != I->getNumOperands() ||
342 getType() != I->getType())
345 // If both instructions have no operands, they are identical.
346 if (getNumOperands() == 0 && I->getNumOperands() == 0)
347 return haveSameSpecialState(this, I);
349 // We have two instructions of identical opcode and #operands. Check to see
350 // if all operands are the same.
351 if (!std::equal(op_begin(), op_end(), I->op_begin()))
354 if (const PHINode *thisPHI = dyn_cast<PHINode>(this)) {
355 const PHINode *otherPHI = cast<PHINode>(I);
356 return std::equal(thisPHI->block_begin(), thisPHI->block_end(),
357 otherPHI->block_begin());
360 return haveSameSpecialState(this, I);
364 // This should be kept in sync with isEquivalentOperation in
365 // lib/Transforms/IPO/MergeFunctions.cpp.
366 bool Instruction::isSameOperationAs(const Instruction *I,
367 unsigned flags) const {
368 bool IgnoreAlignment = flags & CompareIgnoringAlignment;
369 bool UseScalarTypes = flags & CompareUsingScalarTypes;
371 if (getOpcode() != I->getOpcode() ||
372 getNumOperands() != I->getNumOperands() ||
374 getType()->getScalarType() != I->getType()->getScalarType() :
375 getType() != I->getType()))
378 // We have two instructions of identical opcode and #operands. Check to see
379 // if all operands are the same type
380 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
382 getOperand(i)->getType()->getScalarType() !=
383 I->getOperand(i)->getType()->getScalarType() :
384 getOperand(i)->getType() != I->getOperand(i)->getType())
387 return haveSameSpecialState(this, I, IgnoreAlignment);
390 /// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the
391 /// specified block. Note that PHI nodes are considered to evaluate their
392 /// operands in the corresponding predecessor block.
393 bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const {
394 for (const Use &U : uses()) {
395 // PHI nodes uses values in the corresponding predecessor block. For other
396 // instructions, just check to see whether the parent of the use matches up.
397 const Instruction *I = cast<Instruction>(U.getUser());
398 const PHINode *PN = dyn_cast<PHINode>(I);
400 if (I->getParent() != BB)
405 if (PN->getIncomingBlock(U) != BB)
411 /// mayReadFromMemory - Return true if this instruction may read memory.
413 bool Instruction::mayReadFromMemory() const {
414 switch (getOpcode()) {
415 default: return false;
416 case Instruction::VAArg:
417 case Instruction::Load:
418 case Instruction::Fence: // FIXME: refine definition of mayReadFromMemory
419 case Instruction::AtomicCmpXchg:
420 case Instruction::AtomicRMW:
421 case Instruction::CatchPad:
422 case Instruction::CatchRet:
424 case Instruction::Call:
425 return !cast<CallInst>(this)->doesNotAccessMemory();
426 case Instruction::Invoke:
427 return !cast<InvokeInst>(this)->doesNotAccessMemory();
428 case Instruction::Store:
429 return !cast<StoreInst>(this)->isUnordered();
433 /// mayWriteToMemory - Return true if this instruction may modify memory.
435 bool Instruction::mayWriteToMemory() const {
436 switch (getOpcode()) {
437 default: return false;
438 case Instruction::Fence: // FIXME: refine definition of mayWriteToMemory
439 case Instruction::Store:
440 case Instruction::VAArg:
441 case Instruction::AtomicCmpXchg:
442 case Instruction::AtomicRMW:
443 case Instruction::CatchPad:
444 case Instruction::CatchRet:
446 case Instruction::Call:
447 return !cast<CallInst>(this)->onlyReadsMemory();
448 case Instruction::Invoke:
449 return !cast<InvokeInst>(this)->onlyReadsMemory();
450 case Instruction::Load:
451 return !cast<LoadInst>(this)->isUnordered();
455 bool Instruction::isAtomic() const {
456 switch (getOpcode()) {
459 case Instruction::AtomicCmpXchg:
460 case Instruction::AtomicRMW:
461 case Instruction::Fence:
463 case Instruction::Load:
464 return cast<LoadInst>(this)->getOrdering() != NotAtomic;
465 case Instruction::Store:
466 return cast<StoreInst>(this)->getOrdering() != NotAtomic;
470 bool Instruction::mayThrow() const {
471 if (const CallInst *CI = dyn_cast<CallInst>(this))
472 return !CI->doesNotThrow();
473 if (const auto *CRI = dyn_cast<CleanupReturnInst>(this))
474 return CRI->unwindsToCaller();
475 if (const auto *CatchSwitch = dyn_cast<CatchSwitchInst>(this))
476 return CatchSwitch->unwindsToCaller();
477 return isa<ResumeInst>(this);
480 bool Instruction::mayReturn() const {
481 if (const CallInst *CI = dyn_cast<CallInst>(this))
482 return !CI->doesNotReturn();
486 /// isAssociative - Return true if the instruction is associative:
488 /// Associative operators satisfy: x op (y op z) === (x op y) op z
490 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
492 bool Instruction::isAssociative(unsigned Opcode) {
493 return Opcode == And || Opcode == Or || Opcode == Xor ||
494 Opcode == Add || Opcode == Mul;
497 bool Instruction::isAssociative() const {
498 unsigned Opcode = getOpcode();
499 if (isAssociative(Opcode))
505 return cast<FPMathOperator>(this)->hasUnsafeAlgebra();
511 /// isCommutative - Return true if the instruction is commutative:
513 /// Commutative operators satisfy: (x op y) === (y op x)
515 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
516 /// applied to any type.
518 bool Instruction::isCommutative(unsigned op) {
533 /// isIdempotent - Return true if the instruction is idempotent:
535 /// Idempotent operators satisfy: x op x === x
537 /// In LLVM, the And and Or operators are idempotent.
539 bool Instruction::isIdempotent(unsigned Opcode) {
540 return Opcode == And || Opcode == Or;
543 /// isNilpotent - Return true if the instruction is nilpotent:
545 /// Nilpotent operators satisfy: x op x === Id,
547 /// where Id is the identity for the operator, i.e. a constant such that
548 /// x op Id === x and Id op x === x for all x.
550 /// In LLVM, the Xor operator is nilpotent.
552 bool Instruction::isNilpotent(unsigned Opcode) {
553 return Opcode == Xor;
556 Instruction *Instruction::cloneImpl() const {
557 llvm_unreachable("Subclass of Instruction failed to implement cloneImpl");
560 Instruction *Instruction::clone() const {
561 Instruction *New = nullptr;
562 switch (getOpcode()) {
564 llvm_unreachable("Unhandled Opcode.");
565 #define HANDLE_INST(num, opc, clas) \
566 case Instruction::opc: \
567 New = cast<clas>(this)->cloneImpl(); \
569 #include "llvm/IR/Instruction.def"
573 New->SubclassOptionalData = SubclassOptionalData;
577 // Otherwise, enumerate and copy over metadata from the old instruction to the
579 SmallVector<std::pair<unsigned, MDNode *>, 4> TheMDs;
580 getAllMetadataOtherThanDebugLoc(TheMDs);
581 for (const auto &MD : TheMDs)
582 New->setMetadata(MD.first, MD.second);
584 New->setDebugLoc(getDebugLoc());