1//===-- Instruction.cpp - Implement the Instruction class -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements the Instruction class for the VMCore library. 11// 12//===----------------------------------------------------------------------===// 13 14#include "llvm/Instruction.h" 15#include "llvm/Type.h" 16#include "llvm/Instructions.h" 17#include "llvm/Constants.h" 18#include "llvm/Module.h" 19#include "llvm/Support/CallSite.h" 20#include "llvm/Support/LeakDetector.h" 21using namespace llvm; 22 23Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps, 24 Instruction *InsertBefore) 25 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) { 26 // Make sure that we get added to a basicblock 27 LeakDetector::addGarbageObject(this); 28 29 // If requested, insert this instruction into a basic block... 30 if (InsertBefore) { 31 assert(InsertBefore->getParent() && 32 "Instruction to insert before is not in a basic block!"); 33 InsertBefore->getParent()->getInstList().insert(InsertBefore, this); 34 } 35} 36 37Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps, 38 BasicBlock *InsertAtEnd) 39 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) { 40 // Make sure that we get added to a basicblock 41 LeakDetector::addGarbageObject(this); 42 43 // append this instruction into the basic block 44 assert(InsertAtEnd && "Basic block to append to may not be NULL!"); 45 InsertAtEnd->getInstList().push_back(this); 46} 47 48 49// Out of line virtual method, so the vtable, etc has a home. 50Instruction::~Instruction() { 51 assert(Parent == 0 && "Instruction still linked in the program!"); 52 if (hasMetadataHashEntry()) 53 clearMetadataHashEntries(); 54} 55 56 57void Instruction::setParent(BasicBlock *P) { 58 if (getParent()) { 59 if (!P) LeakDetector::addGarbageObject(this); 60 } else { 61 if (P) LeakDetector::removeGarbageObject(this); 62 } 63 64 Parent = P; 65} 66 67void Instruction::removeFromParent() { 68 getParent()->getInstList().remove(this); 69} 70 71void Instruction::eraseFromParent() { 72 getParent()->getInstList().erase(this); 73} 74 75/// insertBefore - Insert an unlinked instructions into a basic block 76/// immediately before the specified instruction. 77void Instruction::insertBefore(Instruction *InsertPos) { 78 InsertPos->getParent()->getInstList().insert(InsertPos, this); 79} 80 81/// insertAfter - Insert an unlinked instructions into a basic block 82/// immediately after the specified instruction. 83void Instruction::insertAfter(Instruction *InsertPos) { 84 InsertPos->getParent()->getInstList().insertAfter(InsertPos, this); 85} 86 87/// moveBefore - Unlink this instruction from its current basic block and 88/// insert it into the basic block that MovePos lives in, right before 89/// MovePos. 90void Instruction::moveBefore(Instruction *MovePos) { 91 MovePos->getParent()->getInstList().splice(MovePos,getParent()->getInstList(), 92 this); 93} 94 95 96const char *Instruction::getOpcodeName(unsigned OpCode) { 97 switch (OpCode) { 98 // Terminators 99 case Ret: return "ret"; 100 case Br: return "br"; 101 case Switch: return "switch"; 102 case IndirectBr: return "indirectbr"; 103 case Invoke: return "invoke"; 104 case Resume: return "resume"; 105 case Unreachable: return "unreachable"; 106 107 // Standard binary operators... 108 case Add: return "add"; 109 case FAdd: return "fadd"; 110 case Sub: return "sub"; 111 case FSub: return "fsub"; 112 case Mul: return "mul"; 113 case FMul: return "fmul"; 114 case UDiv: return "udiv"; 115 case SDiv: return "sdiv"; 116 case FDiv: return "fdiv"; 117 case URem: return "urem"; 118 case SRem: return "srem"; 119 case FRem: return "frem"; 120 121 // Logical operators... 122 case And: return "and"; 123 case Or : return "or"; 124 case Xor: return "xor"; 125 126 // Memory instructions... 127 case Alloca: return "alloca"; 128 case Load: return "load"; 129 case Store: return "store"; 130 case AtomicCmpXchg: return "cmpxchg"; 131 case AtomicRMW: return "atomicrmw"; 132 case Fence: return "fence"; 133 case GetElementPtr: return "getelementptr"; 134 135 // Convert instructions... 136 case Trunc: return "trunc"; 137 case ZExt: return "zext"; 138 case SExt: return "sext"; 139 case FPTrunc: return "fptrunc"; 140 case FPExt: return "fpext"; 141 case FPToUI: return "fptoui"; 142 case FPToSI: return "fptosi"; 143 case UIToFP: return "uitofp"; 144 case SIToFP: return "sitofp"; 145 case IntToPtr: return "inttoptr"; 146 case PtrToInt: return "ptrtoint"; 147 case BitCast: return "bitcast"; 148 149 // Other instructions... 150 case ICmp: return "icmp"; 151 case FCmp: return "fcmp"; 152 case PHI: return "phi"; 153 case Select: return "select"; 154 case Call: return "call"; 155 case Shl: return "shl"; 156 case LShr: return "lshr"; 157 case AShr: return "ashr"; 158 case VAArg: return "va_arg"; 159 case ExtractElement: return "extractelement"; 160 case InsertElement: return "insertelement"; 161 case ShuffleVector: return "shufflevector"; 162 case ExtractValue: return "extractvalue"; 163 case InsertValue: return "insertvalue"; 164 case LandingPad: return "landingpad"; 165 166 default: return "<Invalid operator> "; 167 } 168} 169 170/// isIdenticalTo - Return true if the specified instruction is exactly 171/// identical to the current one. This means that all operands match and any 172/// extra information (e.g. load is volatile) agree. 173bool Instruction::isIdenticalTo(const Instruction *I) const { 174 return isIdenticalToWhenDefined(I) && 175 SubclassOptionalData == I->SubclassOptionalData; 176} 177 178/// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it 179/// ignores the SubclassOptionalData flags, which specify conditions 180/// under which the instruction's result is undefined. 181bool Instruction::isIdenticalToWhenDefined(const Instruction *I) const { 182 if (getOpcode() != I->getOpcode() || 183 getNumOperands() != I->getNumOperands() || 184 getType() != I->getType()) 185 return false; 186 187 // We have two instructions of identical opcode and #operands. Check to see 188 // if all operands are the same. 189 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) 190 if (getOperand(i) != I->getOperand(i)) 191 return false; 192 193 // Check special state that is a part of some instructions. 194 if (const LoadInst *LI = dyn_cast<LoadInst>(this)) 195 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() && 196 LI->getAlignment() == cast<LoadInst>(I)->getAlignment() && 197 LI->getOrdering() == cast<LoadInst>(I)->getOrdering() && 198 LI->getSynchScope() == cast<LoadInst>(I)->getSynchScope(); 199 if (const StoreInst *SI = dyn_cast<StoreInst>(this)) 200 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() && 201 SI->getAlignment() == cast<StoreInst>(I)->getAlignment() && 202 SI->getOrdering() == cast<StoreInst>(I)->getOrdering() && 203 SI->getSynchScope() == cast<StoreInst>(I)->getSynchScope(); 204 if (const CmpInst *CI = dyn_cast<CmpInst>(this)) 205 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate(); 206 if (const CallInst *CI = dyn_cast<CallInst>(this)) 207 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() && 208 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() && 209 CI->getAttributes() == cast<CallInst>(I)->getAttributes(); 210 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this)) 211 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() && 212 CI->getAttributes() == cast<InvokeInst>(I)->getAttributes(); 213 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) 214 return IVI->getIndices() == cast<InsertValueInst>(I)->getIndices(); 215 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) 216 return EVI->getIndices() == cast<ExtractValueInst>(I)->getIndices(); 217 if (const FenceInst *FI = dyn_cast<FenceInst>(this)) 218 return FI->getOrdering() == cast<FenceInst>(FI)->getOrdering() && 219 FI->getSynchScope() == cast<FenceInst>(FI)->getSynchScope(); 220 if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(this)) 221 return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I)->isVolatile() && 222 CXI->getOrdering() == cast<AtomicCmpXchgInst>(I)->getOrdering() && 223 CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I)->getSynchScope(); 224 if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(this)) 225 return RMWI->getOperation() == cast<AtomicRMWInst>(I)->getOperation() && 226 RMWI->isVolatile() == cast<AtomicRMWInst>(I)->isVolatile() && 227 RMWI->getOrdering() == cast<AtomicRMWInst>(I)->getOrdering() && 228 RMWI->getSynchScope() == cast<AtomicRMWInst>(I)->getSynchScope(); 229 if (const PHINode *thisPHI = dyn_cast<PHINode>(this)) { 230 const PHINode *otherPHI = cast<PHINode>(I); 231 for (unsigned i = 0, e = thisPHI->getNumOperands(); i != e; ++i) { 232 if (thisPHI->getIncomingBlock(i) != otherPHI->getIncomingBlock(i)) 233 return false; 234 } 235 return true; 236 } 237 return true; 238} 239 240// isSameOperationAs 241// This should be kept in sync with isEquivalentOperation in 242// lib/Transforms/IPO/MergeFunctions.cpp. 243bool Instruction::isSameOperationAs(const Instruction *I, 244 unsigned flags) const { 245 bool IgnoreAlignment = flags & CompareIgnoringAlignment; 246 bool UseScalarTypes = flags & CompareUsingScalarTypes; 247 248 if (getOpcode() != I->getOpcode() || 249 getNumOperands() != I->getNumOperands() || 250 (UseScalarTypes ? 251 getType()->getScalarType() != I->getType()->getScalarType() : 252 getType() != I->getType())) 253 return false; 254 255 // We have two instructions of identical opcode and #operands. Check to see 256 // if all operands are the same type 257 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) 258 if (UseScalarTypes ? 259 getOperand(i)->getType()->getScalarType() != 260 I->getOperand(i)->getType()->getScalarType() : 261 getOperand(i)->getType() != I->getOperand(i)->getType()) 262 return false; 263 264 // Check special state that is a part of some instructions. 265 if (const LoadInst *LI = dyn_cast<LoadInst>(this)) 266 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() && 267 (LI->getAlignment() == cast<LoadInst>(I)->getAlignment() || 268 IgnoreAlignment) && 269 LI->getOrdering() == cast<LoadInst>(I)->getOrdering() && 270 LI->getSynchScope() == cast<LoadInst>(I)->getSynchScope(); 271 if (const StoreInst *SI = dyn_cast<StoreInst>(this)) 272 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() && 273 (SI->getAlignment() == cast<StoreInst>(I)->getAlignment() || 274 IgnoreAlignment) && 275 SI->getOrdering() == cast<StoreInst>(I)->getOrdering() && 276 SI->getSynchScope() == cast<StoreInst>(I)->getSynchScope(); 277 if (const CmpInst *CI = dyn_cast<CmpInst>(this)) 278 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate(); 279 if (const CallInst *CI = dyn_cast<CallInst>(this)) 280 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() && 281 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() && 282 CI->getAttributes() == cast<CallInst>(I)->getAttributes(); 283 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this)) 284 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() && 285 CI->getAttributes() == 286 cast<InvokeInst>(I)->getAttributes(); 287 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) 288 return IVI->getIndices() == cast<InsertValueInst>(I)->getIndices(); 289 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) 290 return EVI->getIndices() == cast<ExtractValueInst>(I)->getIndices(); 291 if (const FenceInst *FI = dyn_cast<FenceInst>(this)) 292 return FI->getOrdering() == cast<FenceInst>(I)->getOrdering() && 293 FI->getSynchScope() == cast<FenceInst>(I)->getSynchScope(); 294 if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(this)) 295 return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I)->isVolatile() && 296 CXI->getOrdering() == cast<AtomicCmpXchgInst>(I)->getOrdering() && 297 CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I)->getSynchScope(); 298 if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(this)) 299 return RMWI->getOperation() == cast<AtomicRMWInst>(I)->getOperation() && 300 RMWI->isVolatile() == cast<AtomicRMWInst>(I)->isVolatile() && 301 RMWI->getOrdering() == cast<AtomicRMWInst>(I)->getOrdering() && 302 RMWI->getSynchScope() == cast<AtomicRMWInst>(I)->getSynchScope(); 303 304 return true; 305} 306 307/// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the 308/// specified block. Note that PHI nodes are considered to evaluate their 309/// operands in the corresponding predecessor block. 310bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const { 311 for (const_use_iterator UI = use_begin(), E = use_end(); UI != E; ++UI) { 312 // PHI nodes uses values in the corresponding predecessor block. For other 313 // instructions, just check to see whether the parent of the use matches up. 314 const User *U = *UI; 315 const PHINode *PN = dyn_cast<PHINode>(U); 316 if (PN == 0) { 317 if (cast<Instruction>(U)->getParent() != BB) 318 return true; 319 continue; 320 } 321 322 if (PN->getIncomingBlock(UI) != BB) 323 return true; 324 } 325 return false; 326} 327 328/// mayReadFromMemory - Return true if this instruction may read memory. 329/// 330bool Instruction::mayReadFromMemory() const { 331 switch (getOpcode()) { 332 default: return false; 333 case Instruction::VAArg: 334 case Instruction::Load: 335 case Instruction::Fence: // FIXME: refine definition of mayReadFromMemory 336 case Instruction::AtomicCmpXchg: 337 case Instruction::AtomicRMW: 338 return true; 339 case Instruction::Call: 340 return !cast<CallInst>(this)->doesNotAccessMemory(); 341 case Instruction::Invoke: 342 return !cast<InvokeInst>(this)->doesNotAccessMemory(); 343 case Instruction::Store: 344 return !cast<StoreInst>(this)->isUnordered(); 345 } 346} 347 348/// mayWriteToMemory - Return true if this instruction may modify memory. 349/// 350bool Instruction::mayWriteToMemory() const { 351 switch (getOpcode()) { 352 default: return false; 353 case Instruction::Fence: // FIXME: refine definition of mayWriteToMemory 354 case Instruction::Store: 355 case Instruction::VAArg: 356 case Instruction::AtomicCmpXchg: 357 case Instruction::AtomicRMW: 358 return true; 359 case Instruction::Call: 360 return !cast<CallInst>(this)->onlyReadsMemory(); 361 case Instruction::Invoke: 362 return !cast<InvokeInst>(this)->onlyReadsMemory(); 363 case Instruction::Load: 364 return !cast<LoadInst>(this)->isUnordered(); 365 } 366} 367 368/// mayThrow - Return true if this instruction may throw an exception. 369/// 370bool Instruction::mayThrow() const { 371 if (const CallInst *CI = dyn_cast<CallInst>(this)) 372 return !CI->doesNotThrow(); 373 return isa<ResumeInst>(this); 374} 375 376/// isAssociative - Return true if the instruction is associative: 377/// 378/// Associative operators satisfy: x op (y op z) === (x op y) op z 379/// 380/// In LLVM, the Add, Mul, And, Or, and Xor operators are associative. 381/// 382bool Instruction::isAssociative(unsigned Opcode) { 383 return Opcode == And || Opcode == Or || Opcode == Xor || 384 Opcode == Add || Opcode == Mul; 385} 386 387/// isCommutative - Return true if the instruction is commutative: 388/// 389/// Commutative operators satisfy: (x op y) === (y op x) 390/// 391/// In LLVM, these are the associative operators, plus SetEQ and SetNE, when 392/// applied to any type. 393/// 394bool Instruction::isCommutative(unsigned op) { 395 switch (op) { 396 case Add: 397 case FAdd: 398 case Mul: 399 case FMul: 400 case And: 401 case Or: 402 case Xor: 403 return true; 404 default: 405 return false; 406 } 407} 408 409/// isIdempotent - Return true if the instruction is idempotent: 410/// 411/// Idempotent operators satisfy: x op x === x 412/// 413/// In LLVM, the And and Or operators are idempotent. 414/// 415bool Instruction::isIdempotent(unsigned Opcode) { 416 return Opcode == And || Opcode == Or; 417} 418 419/// isNilpotent - Return true if the instruction is nilpotent: 420/// 421/// Nilpotent operators satisfy: x op x === Id, 422/// 423/// where Id is the identity for the operator, i.e. a constant such that 424/// x op Id === x and Id op x === x for all x. 425/// 426/// In LLVM, the Xor operator is nilpotent. 427/// 428bool Instruction::isNilpotent(unsigned Opcode) { 429 return Opcode == Xor; 430} 431 432Instruction *Instruction::clone() const { 433 Instruction *New = clone_impl(); 434 New->SubclassOptionalData = SubclassOptionalData; 435 if (!hasMetadata()) 436 return New; 437 438 // Otherwise, enumerate and copy over metadata from the old instruction to the 439 // new one. 440 SmallVector<std::pair<unsigned, MDNode*>, 4> TheMDs; 441 getAllMetadataOtherThanDebugLoc(TheMDs); 442 for (unsigned i = 0, e = TheMDs.size(); i != e; ++i) 443 New->setMetadata(TheMDs[i].first, TheMDs[i].second); 444 445 New->setDebugLoc(getDebugLoc()); 446 return New; 447} 448