X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FIR%2FValue.cpp;h=925f2058e5592f48dd06ce9cfeab7e9c48fbba15;hb=ded192283600c9bc462017bb2ca81b2c0b419b42;hp=862f08c896627c8c61f6c05b352ecfd25976e4b8;hpb=9ca230f11ccce9591941149d9cff0be326639c8a;p=oota-llvm.git diff --git a/lib/IR/Value.cpp b/lib/IR/Value.cpp index 862f08c8966..925f2058e55 100644 --- a/lib/IR/Value.cpp +++ b/lib/IR/Value.cpp @@ -23,30 +23,31 @@ #include "llvm/IR/GetElementPtrTypeIterator.h" #include "llvm/IR/InstrTypes.h" #include "llvm/IR/Instructions.h" -#include "llvm/IR/LeakDetector.h" +#include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Module.h" #include "llvm/IR/Operator.h" +#include "llvm/IR/Statepoint.h" #include "llvm/IR/ValueHandle.h" #include "llvm/IR/ValueSymbolTable.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/raw_ostream.h" #include using namespace llvm; //===----------------------------------------------------------------------===// // Value Class //===----------------------------------------------------------------------===// - static inline Type *checkType(Type *Ty) { assert(Ty && "Value defined with a null type: Error!"); return Ty; } Value::Value(Type *ty, unsigned scid) - : VTy(checkType(ty)), UseList(nullptr), Name(nullptr), SubclassID(scid), + : VTy(checkType(ty)), UseList(nullptr), SubclassID(scid), HasValueHandle(0), SubclassOptionalData(0), SubclassData(0), - NumOperands(0) { + NumUserOperands(0), IsUsedByMD(false), HasName(false) { // FIXME: Why isn't this in the subclass gunk?? // Note, we cannot call isa before the CallInst has been // constructed. @@ -63,30 +64,33 @@ Value::~Value() { // Notify all ValueHandles (if present) that this value is going away. if (HasValueHandle) ValueHandleBase::ValueIsDeleted(this); + if (isUsedByMetadata()) + ValueAsMetadata::handleDeletion(this); #ifndef NDEBUG // Only in -g mode... // Check to make sure that there are no uses of this value that are still // around when the value is destroyed. If there are, then we have a dangling - // reference and something is wrong. This code is here to print out what is - // still being referenced. The value in question should be printed as - // a + // reference and something is wrong. This code is here to print out where + // the value is still being referenced. // if (!use_empty()) { dbgs() << "While deleting: " << *VTy << " %" << getName() << "\n"; - for (use_iterator I = use_begin(), E = use_end(); I != E; ++I) - dbgs() << "Use still stuck around after Def is destroyed:" - << **I << "\n"; + for (auto *U : users()) + dbgs() << "Use still stuck around after Def is destroyed:" << *U << "\n"; } #endif assert(use_empty() && "Uses remain when a value is destroyed!"); // If this value is named, destroy the name. This should not be in a symtab // at this point. - if (Name && SubclassID != MDStringVal) - Name->Destroy(); + destroyValueName(); +} - // There should be no uses of this object anymore, remove it. - LeakDetector::removeGarbageObject(this); +void Value::destroyValueName() { + ValueName *Name = getValueName(); + if (Name) + Name->Destroy(); + setValueName(nullptr); } bool Value::hasNUses(unsigned N) const { @@ -146,27 +150,51 @@ static bool getSymTab(Value *V, ValueSymbolTable *&ST) { } else if (Argument *A = dyn_cast(V)) { if (Function *P = A->getParent()) ST = &P->getValueSymbolTable(); - } else if (isa(V)) - return true; - else { + } else { assert(isa(V) && "Unknown value type!"); return true; // no name is setable for this. } return false; } +ValueName *Value::getValueName() const { + if (!HasName) return nullptr; + + LLVMContext &Ctx = getContext(); + auto I = Ctx.pImpl->ValueNames.find(this); + assert(I != Ctx.pImpl->ValueNames.end() && + "No name entry found!"); + + return I->second; +} + +void Value::setValueName(ValueName *VN) { + LLVMContext &Ctx = getContext(); + + assert(HasName == Ctx.pImpl->ValueNames.count(this) && + "HasName bit out of sync!"); + + if (!VN) { + if (HasName) + Ctx.pImpl->ValueNames.erase(this); + HasName = false; + return; + } + + HasName = true; + Ctx.pImpl->ValueNames[this] = VN; +} + StringRef Value::getName() const { // Make sure the empty string is still a C string. For historical reasons, // some clients want to call .data() on the result and expect it to be null // terminated. - if (!Name) return StringRef("", 0); - return Name->getKey(); + if (!hasName()) + return StringRef("", 0); + return getValueName()->getKey(); } -void Value::setName(const Twine &NewName) { - assert(SubclassID != MDStringVal && - "Cannot set the name of MDString with this method!"); - +void Value::setNameImpl(const Twine &NewName) { // Fast path for common IRBuilder case of setName("") when there is no name. if (NewName.isTriviallyEmpty() && !hasName()) return; @@ -187,26 +215,20 @@ void Value::setName(const Twine &NewName) { if (getSymTab(this, ST)) return; // Cannot set a name on this value (e.g. constant). - if (Function *F = dyn_cast(this)) - getContext().pImpl->IntrinsicIDCache.erase(F); - if (!ST) { // No symbol table to update? Just do the change. if (NameRef.empty()) { // Free the name for this value. - Name->Destroy(); - Name = nullptr; + destroyValueName(); return; } - if (Name) - Name->Destroy(); - // NOTE: Could optimize for the case the name is shrinking to not deallocate // then reallocated. + destroyValueName(); // Create the new name. - Name = ValueName::Create(NameRef); - Name->setValue(this); + setValueName(ValueName::Create(NameRef)); + getValueName()->setValue(this); return; } @@ -214,21 +236,24 @@ void Value::setName(const Twine &NewName) { // then reallocated. if (hasName()) { // Remove old name. - ST->removeValueName(Name); - Name->Destroy(); - Name = nullptr; + ST->removeValueName(getValueName()); + destroyValueName(); if (NameRef.empty()) return; } // Name is changing to something new. - Name = ST->createValueName(NameRef, this); + setValueName(ST->createValueName(NameRef, this)); } -void Value::takeName(Value *V) { - assert(SubclassID != MDStringVal && "Cannot take the name of an MDString!"); +void Value::setName(const Twine &NewName) { + setNameImpl(NewName); + if (Function *F = dyn_cast(this)) + F->recalculateIntrinsicID(); +} +void Value::takeName(Value *V) { ValueSymbolTable *ST = nullptr; // If this value has a name, drop it. if (hasName()) { @@ -242,9 +267,8 @@ void Value::takeName(Value *V) { // Remove old name. if (ST) - ST->removeValueName(Name); - Name->Destroy(); - Name = nullptr; + ST->removeValueName(getValueName()); + destroyValueName(); } // Now we know that this has no name. @@ -270,9 +294,9 @@ void Value::takeName(Value *V) { // This works even if both values have no symtab yet. if (ST == VST) { // Take the name! - Name = V->Name; - V->Name = nullptr; - Name->setValue(this); + setValueName(V->getValueName()); + V->setValueName(nullptr); + getValueName()->setValue(this); return; } @@ -280,10 +304,10 @@ void Value::takeName(Value *V) { // then reinsert it into ST. if (VST) - VST->removeValueName(V->Name); - Name = V->Name; - V->Name = nullptr; - Name->setValue(this); + VST->removeValueName(V->getValueName()); + setValueName(V->getValueName()); + V->setValueName(nullptr); + getValueName()->setValue(this); if (ST) ST->reinsertValue(this); @@ -292,7 +316,7 @@ void Value::takeName(Value *V) { #ifndef NDEBUG static bool contains(SmallPtrSetImpl &Cache, ConstantExpr *Expr, Constant *C) { - if (!Cache.insert(Expr)) + if (!Cache.insert(Expr).second) return false; for (auto &O : Expr->operands()) { @@ -334,6 +358,8 @@ void Value::replaceAllUsesWith(Value *New) { // Notify all ValueHandles (if present) that this value is going away. if (HasValueHandle) ValueHandleBase::ValueIsRAUWd(this, New); + if (isUsedByMetadata()) + ValueAsMetadata::handleRAUW(this, New); while (!use_empty()) { Use &U = *UseList; @@ -341,7 +367,7 @@ void Value::replaceAllUsesWith(Value *New) { // constant because they are uniqued. if (auto *C = dyn_cast(U.getUser())) { if (!isa(C)) { - C->replaceUsesOfWithOnConstant(this, New, &U); + C->handleOperandChange(this, New, &U); continue; } } @@ -353,6 +379,28 @@ void Value::replaceAllUsesWith(Value *New) { BB->replaceSuccessorsPhiUsesWith(cast(New)); } +// Like replaceAllUsesWith except it does not handle constants or basic blocks. +// This routine leaves uses within BB. +void Value::replaceUsesOutsideBlock(Value *New, BasicBlock *BB) { + assert(New && "Value::replaceUsesOutsideBlock(, BB) is invalid!"); + assert(!contains(New, this) && + "this->replaceUsesOutsideBlock(expr(this), BB) is NOT valid!"); + assert(New->getType() == getType() && + "replaceUses of value with new value of different type!"); + assert(BB && "Basic block that may contain a use of 'New' must be defined\n"); + + use_iterator UI = use_begin(), E = use_end(); + for (; UI != E;) { + Use &U = *UI; + ++UI; + auto *Usr = dyn_cast(U.getUser()); + if (Usr && Usr->getParent() == BB) + continue; + U.set(New); + } + return; +} + namespace { // Various metrics for how much to strip off of pointers. enum PointerStripKind { @@ -401,7 +449,7 @@ static Value *stripPointerCastsAndOffsets(Value *V) { return V; } assert(V->getType()->isPointerTy() && "Unexpected operand type!"); - } while (Visited.insert(V)); + } while (Visited.insert(V).second); return V; } @@ -442,8 +490,7 @@ Value *Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL, return V; Offset = GEPOffset; V = GEP->getPointerOperand(); - } else if (Operator::getOpcode(V) == Instruction::BitCast || - Operator::getOpcode(V) == Instruction::AddrSpaceCast) { + } else if (Operator::getOpcode(V) == Instruction::BitCast) { V = cast(V)->getOperand(0); } else if (GlobalAlias *GA = dyn_cast(V)) { V = GA->getAliasee(); @@ -451,7 +498,7 @@ Value *Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL, return V; } assert(V->getType()->isPointerTy() && "Unexpected operand type!"); - } while (Visited.insert(V)); + } while (Visited.insert(V).second); return V; } @@ -460,133 +507,6 @@ Value *Value::stripInBoundsOffsets() { return stripPointerCastsAndOffsets(this); } -/// \brief Check if Value is always a dereferenceable pointer. -/// -/// Test if V is always a pointer to allocated and suitably aligned memory for -/// a simple load or store. -static bool isDereferenceablePointer(const Value *V, const DataLayout *DL, - SmallPtrSetImpl &Visited) { - // Note that it is not safe to speculate into a malloc'd region because - // malloc may return null. - - // These are obviously ok. - if (isa(V)) return true; - - // It's not always safe to follow a bitcast, for example: - // bitcast i8* (alloca i8) to i32* - // would result in a 4-byte load from a 1-byte alloca. However, - // if we're casting from a pointer from a type of larger size - // to a type of smaller size (or the same size), and the alignment - // is at least as large as for the resulting pointer type, then - // we can look through the bitcast. - if (DL) - if (const BitCastInst* BC = dyn_cast(V)) { - Type *STy = BC->getSrcTy()->getPointerElementType(), - *DTy = BC->getDestTy()->getPointerElementType(); - if (STy->isSized() && DTy->isSized() && - (DL->getTypeStoreSize(STy) >= - DL->getTypeStoreSize(DTy)) && - (DL->getABITypeAlignment(STy) >= - DL->getABITypeAlignment(DTy))) - return isDereferenceablePointer(BC->getOperand(0), DL, Visited); - } - - // Global variables which can't collapse to null are ok. - if (const GlobalVariable *GV = dyn_cast(V)) - return !GV->hasExternalWeakLinkage(); - - // byval arguments are okay. Arguments specifically marked as - // dereferenceable are okay too. - if (const Argument *A = dyn_cast(V)) { - if (A->hasByValAttr()) - return true; - else if (uint64_t Bytes = A->getDereferenceableBytes()) { - Type *Ty = V->getType()->getPointerElementType(); - if (Ty->isSized() && DL && DL->getTypeStoreSize(Ty) <= Bytes) - return true; - } - - return false; - } - - // Return values from call sites specifically marked as dereferenceable are - // also okay. - if (ImmutableCallSite CS = V) { - if (uint64_t Bytes = CS.getDereferenceableBytes(0)) { - Type *Ty = V->getType()->getPointerElementType(); - if (Ty->isSized() && DL && DL->getTypeStoreSize(Ty) <= Bytes) - return true; - } - } - - // For GEPs, determine if the indexing lands within the allocated object. - if (const GEPOperator *GEP = dyn_cast(V)) { - // Conservatively require that the base pointer be fully dereferenceable. - if (!Visited.insert(GEP->getOperand(0))) - return false; - if (!isDereferenceablePointer(GEP->getOperand(0), DL, Visited)) - return false; - // Check the indices. - gep_type_iterator GTI = gep_type_begin(GEP); - for (User::const_op_iterator I = GEP->op_begin()+1, - E = GEP->op_end(); I != E; ++I) { - Value *Index = *I; - Type *Ty = *GTI++; - // Struct indices can't be out of bounds. - if (isa(Ty)) - continue; - ConstantInt *CI = dyn_cast(Index); - if (!CI) - return false; - // Zero is always ok. - if (CI->isZero()) - continue; - // Check to see that it's within the bounds of an array. - ArrayType *ATy = dyn_cast(Ty); - if (!ATy) - return false; - if (CI->getValue().getActiveBits() > 64) - return false; - if (CI->getZExtValue() >= ATy->getNumElements()) - return false; - } - // Indices check out; this is dereferenceable. - return true; - } - - if (const AddrSpaceCastInst *ASC = dyn_cast(V)) - return isDereferenceablePointer(ASC->getOperand(0), DL, Visited); - - // If we don't know, assume the worst. - return false; -} - -bool Value::isDereferenceablePointer(const DataLayout *DL) const { - // When dereferenceability information is provided by a dereferenceable - // attribute, we know exactly how many bytes are dereferenceable. If we can - // determine the exact offset to the attributed variable, we can use that - // information here. - Type *Ty = getType()->getPointerElementType(); - if (Ty->isSized() && DL) { - APInt Offset(DL->getTypeStoreSizeInBits(getType()), 0); - const Value *BV = stripAndAccumulateInBoundsConstantOffsets(*DL, Offset); - - APInt DerefBytes(Offset.getBitWidth(), 0); - if (const Argument *A = dyn_cast(BV)) - DerefBytes = A->getDereferenceableBytes(); - else if (ImmutableCallSite CS = BV) - DerefBytes = CS.getDereferenceableBytes(0); - - if (DerefBytes.getBoolValue() && Offset.isNonNegative()) { - if (DerefBytes.uge(Offset + DL->getTypeStoreSize(Ty))) - return true; - } - } - - SmallPtrSet Visited; - return ::isDereferenceablePointer(this, DL, Visited); -} - Value *Value::DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB) { PHINode *PN = dyn_cast(this); @@ -629,7 +549,7 @@ void ValueHandleBase::AddToExistingUseList(ValueHandleBase **List) { setPrevPtr(List); if (Next) { Next->setPrevPtr(&Next); - assert(VP.getPointer() == Next->VP.getPointer() && "Added to wrong list?"); + assert(V == Next->V && "Added to wrong list?"); } } @@ -644,14 +564,14 @@ void ValueHandleBase::AddToExistingUseListAfter(ValueHandleBase *List) { } void ValueHandleBase::AddToUseList() { - assert(VP.getPointer() && "Null pointer doesn't have a use list!"); + assert(V && "Null pointer doesn't have a use list!"); - LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl; + LLVMContextImpl *pImpl = V->getContext().pImpl; - if (VP.getPointer()->HasValueHandle) { + if (V->HasValueHandle) { // If this value already has a ValueHandle, then it must be in the // ValueHandles map already. - ValueHandleBase *&Entry = pImpl->ValueHandles[VP.getPointer()]; + ValueHandleBase *&Entry = pImpl->ValueHandles[V]; assert(Entry && "Value doesn't have any handles?"); AddToExistingUseList(&Entry); return; @@ -665,10 +585,10 @@ void ValueHandleBase::AddToUseList() { DenseMap &Handles = pImpl->ValueHandles; const void *OldBucketPtr = Handles.getPointerIntoBucketsArray(); - ValueHandleBase *&Entry = Handles[VP.getPointer()]; + ValueHandleBase *&Entry = Handles[V]; assert(!Entry && "Value really did already have handles?"); AddToExistingUseList(&Entry); - VP.getPointer()->HasValueHandle = true; + V->HasValueHandle = true; // If reallocation didn't happen or if this was the first insertion, don't // walk the table. @@ -680,14 +600,14 @@ void ValueHandleBase::AddToUseList() { // Okay, reallocation did happen. Fix the Prev Pointers. for (DenseMap::iterator I = Handles.begin(), E = Handles.end(); I != E; ++I) { - assert(I->second && I->first == I->second->VP.getPointer() && + assert(I->second && I->first == I->second->V && "List invariant broken!"); I->second->setPrevPtr(&I->second); } } void ValueHandleBase::RemoveFromUseList() { - assert(VP.getPointer() && VP.getPointer()->HasValueHandle && + assert(V && V->HasValueHandle && "Pointer doesn't have a use list!"); // Unlink this from its use list. @@ -704,11 +624,11 @@ void ValueHandleBase::RemoveFromUseList() { // If the Next pointer was null, then it is possible that this was the last // ValueHandle watching VP. If so, delete its entry from the ValueHandles // map. - LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl; + LLVMContextImpl *pImpl = V->getContext().pImpl; DenseMap &Handles = pImpl->ValueHandles; if (Handles.isPointerIntoBucketsArray(PrevPtr)) { - Handles.erase(VP.getPointer()); - VP.getPointer()->HasValueHandle = false; + Handles.erase(V); + V->HasValueHandle = false; } } @@ -773,6 +693,8 @@ void ValueHandleBase::ValueIsDeleted(Value *V) { void ValueHandleBase::ValueIsRAUWd(Value *Old, Value *New) { assert(Old->HasValueHandle &&"Should only be called if ValueHandles present"); assert(Old != New && "Changing value into itself!"); + assert(Old->getType() == New->getType() && + "replaceAllUses of value with new value of different type!"); // Get the linked list base, which is guaranteed to exist since the // HasValueHandle flag is set.