| //===-- Instruction.cpp - Implement the Instruction class -----------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the Instruction class for the VMCore library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Instruction.h" |
| #include "llvm/Type.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/Constants.h" |
| #include "llvm/Module.h" |
| #include "llvm/Support/CallSite.h" |
| #include "llvm/Support/LeakDetector.h" |
| using namespace llvm; |
| |
| Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps, |
| Instruction *InsertBefore) |
| : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) { |
| // Make sure that we get added to a basicblock |
| LeakDetector::addGarbageObject(this); |
| |
| // If requested, insert this instruction into a basic block... |
| if (InsertBefore) { |
| assert(InsertBefore->getParent() && |
| "Instruction to insert before is not in a basic block!"); |
| InsertBefore->getParent()->getInstList().insert(InsertBefore, this); |
| } |
| } |
| |
| Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps, |
| BasicBlock *InsertAtEnd) |
| : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) { |
| // Make sure that we get added to a basicblock |
| LeakDetector::addGarbageObject(this); |
| |
| // append this instruction into the basic block |
| assert(InsertAtEnd && "Basic block to append to may not be NULL!"); |
| InsertAtEnd->getInstList().push_back(this); |
| } |
| |
| |
| // Out of line virtual method, so the vtable, etc has a home. |
| Instruction::~Instruction() { |
| assert(Parent == 0 && "Instruction still linked in the program!"); |
| if (hasMetadataHashEntry()) |
| clearMetadataHashEntries(); |
| } |
| |
| |
| void Instruction::setParent(BasicBlock *P) { |
| if (getParent()) { |
| if (!P) LeakDetector::addGarbageObject(this); |
| } else { |
| if (P) LeakDetector::removeGarbageObject(this); |
| } |
| |
| Parent = P; |
| } |
| |
| void Instruction::removeFromParent() { |
| getParent()->getInstList().remove(this); |
| } |
| |
| void Instruction::eraseFromParent() { |
| getParent()->getInstList().erase(this); |
| } |
| |
| /// insertBefore - Insert an unlinked instructions into a basic block |
| /// immediately before the specified instruction. |
| void Instruction::insertBefore(Instruction *InsertPos) { |
| InsertPos->getParent()->getInstList().insert(InsertPos, this); |
| } |
| |
| /// insertAfter - Insert an unlinked instructions into a basic block |
| /// immediately after the specified instruction. |
| void Instruction::insertAfter(Instruction *InsertPos) { |
| InsertPos->getParent()->getInstList().insertAfter(InsertPos, this); |
| } |
| |
| /// moveBefore - Unlink this instruction from its current basic block and |
| /// insert it into the basic block that MovePos lives in, right before |
| /// MovePos. |
| void Instruction::moveBefore(Instruction *MovePos) { |
| MovePos->getParent()->getInstList().splice(MovePos,getParent()->getInstList(), |
| this); |
| } |
| |
| |
| const char *Instruction::getOpcodeName(unsigned OpCode) { |
| switch (OpCode) { |
| // Terminators |
| case Ret: return "ret"; |
| case Br: return "br"; |
| case Switch: return "switch"; |
| case IndirectBr: return "indirectbr"; |
| case Invoke: return "invoke"; |
| case Resume: return "resume"; |
| case Unwind: return "unwind"; |
| case Unreachable: return "unreachable"; |
| |
| // Standard binary operators... |
| case Add: return "add"; |
| case FAdd: return "fadd"; |
| case Sub: return "sub"; |
| case FSub: return "fsub"; |
| case Mul: return "mul"; |
| case FMul: return "fmul"; |
| case UDiv: return "udiv"; |
| case SDiv: return "sdiv"; |
| case FDiv: return "fdiv"; |
| case URem: return "urem"; |
| case SRem: return "srem"; |
| case FRem: return "frem"; |
| |
| // Logical operators... |
| case And: return "and"; |
| case Or : return "or"; |
| case Xor: return "xor"; |
| |
| // Memory instructions... |
| case Alloca: return "alloca"; |
| case Load: return "load"; |
| case Store: return "store"; |
| case AtomicCmpXchg: return "cmpxchg"; |
| case AtomicRMW: return "atomicrmw"; |
| case Fence: return "fence"; |
| case GetElementPtr: return "getelementptr"; |
| |
| // Convert instructions... |
| case Trunc: return "trunc"; |
| case ZExt: return "zext"; |
| case SExt: return "sext"; |
| case FPTrunc: return "fptrunc"; |
| case FPExt: return "fpext"; |
| case FPToUI: return "fptoui"; |
| case FPToSI: return "fptosi"; |
| case UIToFP: return "uitofp"; |
| case SIToFP: return "sitofp"; |
| case IntToPtr: return "inttoptr"; |
| case PtrToInt: return "ptrtoint"; |
| case BitCast: return "bitcast"; |
| |
| // Other instructions... |
| case ICmp: return "icmp"; |
| case FCmp: return "fcmp"; |
| case PHI: return "phi"; |
| case Select: return "select"; |
| case Call: return "call"; |
| case Shl: return "shl"; |
| case LShr: return "lshr"; |
| case AShr: return "ashr"; |
| case VAArg: return "va_arg"; |
| case ExtractElement: return "extractelement"; |
| case InsertElement: return "insertelement"; |
| case ShuffleVector: return "shufflevector"; |
| case ExtractValue: return "extractvalue"; |
| case InsertValue: return "insertvalue"; |
| |
| default: return "<Invalid operator> "; |
| } |
| |
| return 0; |
| } |
| |
| /// 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 Instruction::isIdenticalTo(const Instruction *I) const { |
| return isIdenticalToWhenDefined(I) && |
| SubclassOptionalData == I->SubclassOptionalData; |
| } |
| |
| /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it |
| /// ignores the SubclassOptionalData flags, which specify conditions |
| /// under which the instruction's result is undefined. |
| bool Instruction::isIdenticalToWhenDefined(const Instruction *I) const { |
| if (getOpcode() != I->getOpcode() || |
| getNumOperands() != I->getNumOperands() || |
| getType() != I->getType()) |
| return false; |
| |
| // We have two instructions of identical opcode and #operands. Check to see |
| // if all operands are the same. |
| for (unsigned i = 0, e = getNumOperands(); i != e; ++i) |
| if (getOperand(i) != I->getOperand(i)) |
| return false; |
| |
| // Check special state that is a part of some instructions. |
| if (const LoadInst *LI = dyn_cast<LoadInst>(this)) |
| return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() && |
| LI->getAlignment() == cast<LoadInst>(I)->getAlignment(); |
| if (const StoreInst *SI = dyn_cast<StoreInst>(this)) |
| return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() && |
| SI->getAlignment() == cast<StoreInst>(I)->getAlignment(); |
| if (const CmpInst *CI = dyn_cast<CmpInst>(this)) |
| return CI->getPredicate() == cast<CmpInst>(I)->getPredicate(); |
| if (const CallInst *CI = dyn_cast<CallInst>(this)) |
| return CI->isTailCall() == cast<CallInst>(I)->isTailCall() && |
| CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() && |
| CI->getAttributes() == cast<CallInst>(I)->getAttributes(); |
| if (const InvokeInst *CI = dyn_cast<InvokeInst>(this)) |
| return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() && |
| CI->getAttributes() == cast<InvokeInst>(I)->getAttributes(); |
| if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) |
| return IVI->getIndices() == cast<InsertValueInst>(I)->getIndices(); |
| if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) |
| return EVI->getIndices() == cast<ExtractValueInst>(I)->getIndices(); |
| if (const FenceInst *FI = dyn_cast<FenceInst>(this)) |
| return FI->getOrdering() == cast<FenceInst>(FI)->getOrdering() && |
| FI->getSynchScope() == cast<FenceInst>(FI)->getSynchScope(); |
| if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(this)) |
| return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I)->isVolatile() && |
| CXI->getOrdering() == cast<AtomicCmpXchgInst>(I)->getOrdering() && |
| CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I)->getSynchScope(); |
| if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(this)) |
| return RMWI->getOperation() == cast<AtomicRMWInst>(I)->getOperation() && |
| RMWI->isVolatile() == cast<AtomicRMWInst>(I)->isVolatile() && |
| RMWI->getOrdering() == cast<AtomicRMWInst>(I)->getOrdering() && |
| RMWI->getSynchScope() == cast<AtomicRMWInst>(I)->getSynchScope(); |
| |
| return true; |
| } |
| |
| // isSameOperationAs |
| // This should be kept in sync with isEquivalentOperation in |
| // lib/Transforms/IPO/MergeFunctions.cpp. |
| bool Instruction::isSameOperationAs(const Instruction *I) const { |
| if (getOpcode() != I->getOpcode() || |
| getNumOperands() != I->getNumOperands() || |
| getType() != I->getType()) |
| return false; |
| |
| // We have two instructions of identical opcode and #operands. Check to see |
| // if all operands are the same type |
| for (unsigned i = 0, e = getNumOperands(); i != e; ++i) |
| if (getOperand(i)->getType() != I->getOperand(i)->getType()) |
| return false; |
| |
| // Check special state that is a part of some instructions. |
| if (const LoadInst *LI = dyn_cast<LoadInst>(this)) |
| return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() && |
| LI->getAlignment() == cast<LoadInst>(I)->getAlignment(); |
| if (const StoreInst *SI = dyn_cast<StoreInst>(this)) |
| return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() && |
| SI->getAlignment() == cast<StoreInst>(I)->getAlignment(); |
| if (const CmpInst *CI = dyn_cast<CmpInst>(this)) |
| return CI->getPredicate() == cast<CmpInst>(I)->getPredicate(); |
| if (const CallInst *CI = dyn_cast<CallInst>(this)) |
| return CI->isTailCall() == cast<CallInst>(I)->isTailCall() && |
| CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() && |
| CI->getAttributes() == cast<CallInst>(I)->getAttributes(); |
| if (const InvokeInst *CI = dyn_cast<InvokeInst>(this)) |
| return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() && |
| CI->getAttributes() == |
| cast<InvokeInst>(I)->getAttributes(); |
| if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) |
| return IVI->getIndices() == cast<InsertValueInst>(I)->getIndices(); |
| if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) |
| return EVI->getIndices() == cast<ExtractValueInst>(I)->getIndices(); |
| if (const FenceInst *FI = dyn_cast<FenceInst>(this)) |
| return FI->getOrdering() == cast<FenceInst>(I)->getOrdering() && |
| FI->getSynchScope() == cast<FenceInst>(I)->getSynchScope(); |
| if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(this)) |
| return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I)->isVolatile() && |
| CXI->getOrdering() == cast<AtomicCmpXchgInst>(I)->getOrdering() && |
| CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I)->getSynchScope(); |
| if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(this)) |
| return RMWI->getOperation() == cast<AtomicRMWInst>(I)->getOperation() && |
| RMWI->isVolatile() == cast<AtomicRMWInst>(I)->isVolatile() && |
| RMWI->getOrdering() == cast<AtomicRMWInst>(I)->getOrdering() && |
| RMWI->getSynchScope() == cast<AtomicRMWInst>(I)->getSynchScope(); |
| |
| return true; |
| } |
| |
| /// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the |
| /// specified block. Note that PHI nodes are considered to evaluate their |
| /// operands in the corresponding predecessor block. |
| bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const { |
| for (const_use_iterator UI = use_begin(), E = use_end(); UI != E; ++UI) { |
| // PHI nodes uses values in the corresponding predecessor block. For other |
| // instructions, just check to see whether the parent of the use matches up. |
| const User *U = *UI; |
| const PHINode *PN = dyn_cast<PHINode>(U); |
| if (PN == 0) { |
| if (cast<Instruction>(U)->getParent() != BB) |
| return true; |
| continue; |
| } |
| |
| if (PN->getIncomingBlock(UI) != BB) |
| return true; |
| } |
| return false; |
| } |
| |
| /// mayReadFromMemory - Return true if this instruction may read memory. |
| /// |
| bool Instruction::mayReadFromMemory() const { |
| switch (getOpcode()) { |
| default: return false; |
| case Instruction::VAArg: |
| case Instruction::Load: |
| case Instruction::Fence: // FIXME: refine definition of mayReadFromMemory |
| case Instruction::AtomicCmpXchg: |
| case Instruction::AtomicRMW: |
| return true; |
| case Instruction::Call: |
| return !cast<CallInst>(this)->doesNotAccessMemory(); |
| case Instruction::Invoke: |
| return !cast<InvokeInst>(this)->doesNotAccessMemory(); |
| case Instruction::Store: |
| return cast<StoreInst>(this)->isVolatile(); |
| } |
| } |
| |
| /// mayWriteToMemory - Return true if this instruction may modify memory. |
| /// |
| bool Instruction::mayWriteToMemory() const { |
| switch (getOpcode()) { |
| default: return false; |
| case Instruction::Fence: // FIXME: refine definition of mayWriteToMemory |
| case Instruction::Store: |
| case Instruction::VAArg: |
| case Instruction::AtomicCmpXchg: |
| case Instruction::AtomicRMW: |
| return true; |
| case Instruction::Call: |
| return !cast<CallInst>(this)->onlyReadsMemory(); |
| case Instruction::Invoke: |
| return !cast<InvokeInst>(this)->onlyReadsMemory(); |
| case Instruction::Load: |
| return cast<LoadInst>(this)->isVolatile(); |
| } |
| } |
| |
| /// mayThrow - Return true if this instruction may throw an exception. |
| /// |
| bool Instruction::mayThrow() const { |
| if (const CallInst *CI = dyn_cast<CallInst>(this)) |
| return !CI->doesNotThrow(); |
| return false; |
| } |
| |
| /// isAssociative - 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 Instruction::isAssociative(unsigned Opcode) { |
| return Opcode == And || Opcode == Or || Opcode == Xor || |
| Opcode == Add || Opcode == Mul; |
| } |
| |
| /// isCommutative - Return true if the instruction is commutative: |
| /// |
| /// Commutative operators satisfy: (x op y) === (y op x) |
| /// |
| /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when |
| /// applied to any type. |
| /// |
| bool Instruction::isCommutative(unsigned op) { |
| switch (op) { |
| case Add: |
| case FAdd: |
| case Mul: |
| case FMul: |
| case And: |
| case Or: |
| case Xor: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| bool Instruction::isSafeToSpeculativelyExecute() const { |
| for (unsigned i = 0, e = getNumOperands(); i != e; ++i) |
| if (Constant *C = dyn_cast<Constant>(getOperand(i))) |
| if (C->canTrap()) |
| return false; |
| |
| switch (getOpcode()) { |
| default: |
| return true; |
| case UDiv: |
| case URem: { |
| // x / y is undefined if y == 0, but calcuations like x / 3 are safe. |
| ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1)); |
| return Op && !Op->isNullValue(); |
| } |
| case SDiv: |
| case SRem: { |
| // x / y is undefined if y == 0, and might be undefined if y == -1, |
| // but calcuations like x / 3 are safe. |
| ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1)); |
| return Op && !Op->isNullValue() && !Op->isAllOnesValue(); |
| } |
| case Load: { |
| const LoadInst *LI = cast<LoadInst>(this); |
| if (LI->isVolatile()) |
| return false; |
| return LI->getPointerOperand()->isDereferenceablePointer(); |
| } |
| case Call: |
| return false; // The called function could have undefined behavior or |
| // side-effects. |
| // FIXME: We should special-case some intrinsics (bswap, |
| // overflow-checking arithmetic, etc.) |
| case VAArg: |
| case Alloca: |
| case Invoke: |
| case PHI: |
| case Store: |
| case Ret: |
| case Br: |
| case IndirectBr: |
| case Switch: |
| case Unwind: |
| case Unreachable: |
| case Fence: |
| return false; // Misc instructions which have effects |
| } |
| } |
| |
| Instruction *Instruction::clone() const { |
| Instruction *New = clone_impl(); |
| New->SubclassOptionalData = SubclassOptionalData; |
| if (!hasMetadata()) |
| return New; |
| |
| // Otherwise, enumerate and copy over metadata from the old instruction to the |
| // new one. |
| SmallVector<std::pair<unsigned, MDNode*>, 4> TheMDs; |
| getAllMetadataOtherThanDebugLoc(TheMDs); |
| for (unsigned i = 0, e = TheMDs.size(); i != e; ++i) |
| New->setMetadata(TheMDs[i].first, TheMDs[i].second); |
| |
| New->setDebugLoc(getDebugLoc()); |
| return New; |
| } |