| //===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the MapValue function, which is shared by various parts of |
| // the lib/Transforms/Utils library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Transforms/Utils/ValueMapper.h" |
| #include "llvm/IR/CallSite.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/InlineAsm.h" |
| #include "llvm/IR/Instructions.h" |
| #include "llvm/IR/Metadata.h" |
| using namespace llvm; |
| |
| // Out of line method to get vtable etc for class. |
| void ValueMapTypeRemapper::anchor() {} |
| void ValueMaterializer::anchor() {} |
| |
| Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| ValueToValueMapTy::iterator I = VM.find(V); |
| |
| // If the value already exists in the map, use it. |
| if (I != VM.end() && I->second) return I->second; |
| |
| // If we have a materializer and it can materialize a value, use that. |
| if (Materializer) { |
| if (Value *NewV = Materializer->materializeValueFor(const_cast<Value*>(V))) |
| return VM[V] = NewV; |
| } |
| |
| // Global values do not need to be seeded into the VM if they |
| // are using the identity mapping. |
| if (isa<GlobalValue>(V)) |
| return VM[V] = const_cast<Value*>(V); |
| |
| if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) { |
| // Inline asm may need *type* remapping. |
| FunctionType *NewTy = IA->getFunctionType(); |
| if (TypeMapper) { |
| NewTy = cast<FunctionType>(TypeMapper->remapType(NewTy)); |
| |
| if (NewTy != IA->getFunctionType()) |
| V = InlineAsm::get(NewTy, IA->getAsmString(), IA->getConstraintString(), |
| IA->hasSideEffects(), IA->isAlignStack()); |
| } |
| |
| return VM[V] = const_cast<Value*>(V); |
| } |
| |
| if (const auto *MDV = dyn_cast<MetadataAsValue>(V)) { |
| const Metadata *MD = MDV->getMetadata(); |
| // If this is a module-level metadata and we know that nothing at the module |
| // level is changing, then use an identity mapping. |
| if (!isa<LocalAsMetadata>(MD) && (Flags & RF_NoModuleLevelChanges)) |
| return VM[V] = const_cast<Value *>(V); |
| |
| auto *MappedMD = MapMetadata(MD, VM, Flags, TypeMapper, Materializer); |
| if (MD == MappedMD || (!MappedMD && (Flags & RF_IgnoreMissingEntries))) |
| return VM[V] = const_cast<Value *>(V); |
| |
| // FIXME: This assert crashes during bootstrap, but I think it should be |
| // correct. For now, just match behaviour from before the metadata/value |
| // split. |
| // |
| // assert(MappedMD && "Referenced metadata value not in value map"); |
| return VM[V] = MetadataAsValue::get(V->getContext(), MappedMD); |
| } |
| |
| // Okay, this either must be a constant (which may or may not be mappable) or |
| // is something that is not in the mapping table. |
| Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V)); |
| if (!C) |
| return nullptr; |
| |
| if (BlockAddress *BA = dyn_cast<BlockAddress>(C)) { |
| Function *F = |
| cast<Function>(MapValue(BA->getFunction(), VM, Flags, TypeMapper, Materializer)); |
| BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(), VM, |
| Flags, TypeMapper, Materializer)); |
| return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock()); |
| } |
| |
| // Otherwise, we have some other constant to remap. Start by checking to see |
| // if all operands have an identity remapping. |
| unsigned OpNo = 0, NumOperands = C->getNumOperands(); |
| Value *Mapped = nullptr; |
| for (; OpNo != NumOperands; ++OpNo) { |
| Value *Op = C->getOperand(OpNo); |
| Mapped = MapValue(Op, VM, Flags, TypeMapper, Materializer); |
| if (Mapped != C) break; |
| } |
| |
| // See if the type mapper wants to remap the type as well. |
| Type *NewTy = C->getType(); |
| if (TypeMapper) |
| NewTy = TypeMapper->remapType(NewTy); |
| |
| // If the result type and all operands match up, then just insert an identity |
| // mapping. |
| if (OpNo == NumOperands && NewTy == C->getType()) |
| return VM[V] = C; |
| |
| // Okay, we need to create a new constant. We've already processed some or |
| // all of the operands, set them all up now. |
| SmallVector<Constant*, 8> Ops; |
| Ops.reserve(NumOperands); |
| for (unsigned j = 0; j != OpNo; ++j) |
| Ops.push_back(cast<Constant>(C->getOperand(j))); |
| |
| // If one of the operands mismatch, push it and the other mapped operands. |
| if (OpNo != NumOperands) { |
| Ops.push_back(cast<Constant>(Mapped)); |
| |
| // Map the rest of the operands that aren't processed yet. |
| for (++OpNo; OpNo != NumOperands; ++OpNo) |
| Ops.push_back(MapValue(cast<Constant>(C->getOperand(OpNo)), VM, |
| Flags, TypeMapper, Materializer)); |
| } |
| |
| if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) |
| return VM[V] = CE->getWithOperands(Ops, NewTy); |
| if (isa<ConstantArray>(C)) |
| return VM[V] = ConstantArray::get(cast<ArrayType>(NewTy), Ops); |
| if (isa<ConstantStruct>(C)) |
| return VM[V] = ConstantStruct::get(cast<StructType>(NewTy), Ops); |
| if (isa<ConstantVector>(C)) |
| return VM[V] = ConstantVector::get(Ops); |
| // If this is a no-operand constant, it must be because the type was remapped. |
| if (isa<UndefValue>(C)) |
| return VM[V] = UndefValue::get(NewTy); |
| if (isa<ConstantAggregateZero>(C)) |
| return VM[V] = ConstantAggregateZero::get(NewTy); |
| assert(isa<ConstantPointerNull>(C)); |
| return VM[V] = ConstantPointerNull::get(cast<PointerType>(NewTy)); |
| } |
| |
| static Metadata *mapToMetadata(ValueToValueMapTy &VM, const Metadata *Key, |
| Metadata *Val) { |
| VM.MD()[Key].reset(Val); |
| return Val; |
| } |
| |
| static Metadata *mapToSelf(ValueToValueMapTy &VM, const Metadata *MD) { |
| return mapToMetadata(VM, MD, const_cast<Metadata *>(MD)); |
| } |
| |
| static Metadata *MapMetadataImpl(const Metadata *MD, |
| SmallVectorImpl<MDNode *> &Cycles, |
| ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer); |
| |
| static Metadata *mapMetadataOp(Metadata *Op, SmallVectorImpl<MDNode *> &Cycles, |
| ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| if (!Op) |
| return nullptr; |
| if (Metadata *MappedOp = |
| MapMetadataImpl(Op, Cycles, VM, Flags, TypeMapper, Materializer)) |
| return MappedOp; |
| // Use identity map if MappedOp is null and we can ignore missing entries. |
| if (Flags & RF_IgnoreMissingEntries) |
| return Op; |
| |
| // FIXME: This assert crashes during bootstrap, but I think it should be |
| // correct. For now, just match behaviour from before the metadata/value |
| // split. |
| // |
| // llvm_unreachable("Referenced metadata not in value map!"); |
| return nullptr; |
| } |
| |
| /// \brief Remap nodes. |
| /// |
| /// Insert \c NewNode in the value map, and then remap \c OldNode's operands. |
| /// Assumes that \c NewNode is already a clone of \c OldNode. |
| /// |
| /// \pre \c NewNode is a clone of \c OldNode. |
| static bool remap(const MDNode *OldNode, MDNode *NewNode, |
| SmallVectorImpl<MDNode *> &Cycles, ValueToValueMapTy &VM, |
| RemapFlags Flags, ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| assert(OldNode->getNumOperands() == NewNode->getNumOperands() && |
| "Expected nodes to match"); |
| assert(OldNode->isResolved() && "Expected resolved node"); |
| assert(!NewNode->isUniqued() && "Expected non-uniqued node"); |
| |
| // Map the node upfront so it's available for cyclic references. |
| mapToMetadata(VM, OldNode, NewNode); |
| bool AnyChanged = false; |
| for (unsigned I = 0, E = OldNode->getNumOperands(); I != E; ++I) { |
| Metadata *Old = OldNode->getOperand(I); |
| assert(NewNode->getOperand(I) == Old && |
| "Expected old operands to already be in place"); |
| |
| Metadata *New = mapMetadataOp(OldNode->getOperand(I), Cycles, VM, Flags, |
| TypeMapper, Materializer); |
| if (Old != New) { |
| AnyChanged = true; |
| NewNode->replaceOperandWith(I, New); |
| } |
| } |
| |
| return AnyChanged; |
| } |
| |
| /// \brief Map a distinct MDNode. |
| /// |
| /// Distinct nodes are not uniqued, so they must always recreated. |
| static Metadata *mapDistinctNode(const MDNode *Node, |
| SmallVectorImpl<MDNode *> &Cycles, |
| ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| assert(Node->isDistinct() && "Expected distinct node"); |
| |
| MDNode *NewMD = MDNode::replaceWithDistinct(Node->clone()); |
| remap(Node, NewMD, Cycles, VM, Flags, TypeMapper, Materializer); |
| |
| // Track any cycles beneath this node. |
| for (Metadata *Op : NewMD->operands()) |
| if (auto *Node = dyn_cast_or_null<MDNode>(Op)) |
| if (!Node->isResolved()) |
| Cycles.push_back(Node); |
| |
| return NewMD; |
| } |
| |
| /// \brief Map a uniqued MDNode. |
| /// |
| /// Uniqued nodes may not need to be recreated (they may map to themselves). |
| static Metadata *mapUniquedNode(const MDNode *Node, |
| SmallVectorImpl<MDNode *> &Cycles, |
| ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| assert(Node->isUniqued() && "Expected uniqued node"); |
| |
| // Create a temporary node upfront in case we have a metadata cycle. |
| auto ClonedMD = Node->clone(); |
| if (!remap(Node, ClonedMD.get(), Cycles, VM, Flags, TypeMapper, Materializer)) |
| // No operands changed, so use the identity mapping. |
| return mapToSelf(VM, Node); |
| |
| // At least one operand has changed, so uniquify the cloned node. |
| return mapToMetadata(VM, Node, |
| MDNode::replaceWithUniqued(std::move(ClonedMD))); |
| } |
| |
| static Metadata *MapMetadataImpl(const Metadata *MD, |
| SmallVectorImpl<MDNode *> &Cycles, |
| ValueToValueMapTy &VM, RemapFlags Flags, |
| ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| // If the value already exists in the map, use it. |
| if (Metadata *NewMD = VM.MD().lookup(MD).get()) |
| return NewMD; |
| |
| if (isa<MDString>(MD)) |
| return mapToSelf(VM, MD); |
| |
| if (isa<ConstantAsMetadata>(MD)) |
| if ((Flags & RF_NoModuleLevelChanges)) |
| return mapToSelf(VM, MD); |
| |
| if (const auto *VMD = dyn_cast<ValueAsMetadata>(MD)) { |
| Value *MappedV = |
| MapValue(VMD->getValue(), VM, Flags, TypeMapper, Materializer); |
| if (VMD->getValue() == MappedV || |
| (!MappedV && (Flags & RF_IgnoreMissingEntries))) |
| return mapToSelf(VM, MD); |
| |
| // FIXME: This assert crashes during bootstrap, but I think it should be |
| // correct. For now, just match behaviour from before the metadata/value |
| // split. |
| // |
| // assert(MappedV && "Referenced metadata not in value map!"); |
| if (MappedV) |
| return mapToMetadata(VM, MD, ValueAsMetadata::get(MappedV)); |
| return nullptr; |
| } |
| |
| // Note: this cast precedes the Flags check so we always get its associated |
| // assertion. |
| const MDNode *Node = cast<MDNode>(MD); |
| |
| // If this is a module-level metadata and we know that nothing at the |
| // module level is changing, then use an identity mapping. |
| if (Flags & RF_NoModuleLevelChanges) |
| return mapToSelf(VM, MD); |
| |
| // Require resolved nodes whenever metadata might be remapped. |
| assert(Node->isResolved() && "Unexpected unresolved node"); |
| |
| if (Node->isDistinct()) |
| return mapDistinctNode(Node, Cycles, VM, Flags, TypeMapper, Materializer); |
| |
| return mapUniquedNode(Node, Cycles, VM, Flags, TypeMapper, Materializer); |
| } |
| |
| Metadata *llvm::MapMetadata(const Metadata *MD, ValueToValueMapTy &VM, |
| RemapFlags Flags, ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| SmallVector<MDNode *, 8> Cycles; |
| Metadata *NewMD = |
| MapMetadataImpl(MD, Cycles, VM, Flags, TypeMapper, Materializer); |
| |
| // Resolve cycles underneath MD. |
| if (NewMD && NewMD != MD) { |
| if (auto *N = dyn_cast<MDNode>(NewMD)) |
| if (!N->isResolved()) |
| N->resolveCycles(); |
| |
| for (MDNode *N : Cycles) |
| if (!N->isResolved()) |
| N->resolveCycles(); |
| } else { |
| // Shouldn't get unresolved cycles if nothing was remapped. |
| assert(Cycles.empty() && "Expected no unresolved cycles"); |
| } |
| |
| return NewMD; |
| } |
| |
| MDNode *llvm::MapMetadata(const MDNode *MD, ValueToValueMapTy &VM, |
| RemapFlags Flags, ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer) { |
| return cast<MDNode>(MapMetadata(static_cast<const Metadata *>(MD), VM, Flags, |
| TypeMapper, Materializer)); |
| } |
| |
| /// RemapInstruction - Convert the instruction operands from referencing the |
| /// current values into those specified by VMap. |
| /// |
| void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap, |
| RemapFlags Flags, ValueMapTypeRemapper *TypeMapper, |
| ValueMaterializer *Materializer){ |
| // Remap operands. |
| for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) { |
| Value *V = MapValue(*op, VMap, Flags, TypeMapper, Materializer); |
| // If we aren't ignoring missing entries, assert that something happened. |
| if (V) |
| *op = V; |
| else |
| assert((Flags & RF_IgnoreMissingEntries) && |
| "Referenced value not in value map!"); |
| } |
| |
| // Remap phi nodes' incoming blocks. |
| if (PHINode *PN = dyn_cast<PHINode>(I)) { |
| for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { |
| Value *V = MapValue(PN->getIncomingBlock(i), VMap, Flags); |
| // If we aren't ignoring missing entries, assert that something happened. |
| if (V) |
| PN->setIncomingBlock(i, cast<BasicBlock>(V)); |
| else |
| assert((Flags & RF_IgnoreMissingEntries) && |
| "Referenced block not in value map!"); |
| } |
| } |
| |
| // Remap attached metadata. |
| SmallVector<std::pair<unsigned, MDNode *>, 4> MDs; |
| I->getAllMetadata(MDs); |
| for (SmallVectorImpl<std::pair<unsigned, MDNode *>>::iterator |
| MI = MDs.begin(), |
| ME = MDs.end(); |
| MI != ME; ++MI) { |
| MDNode *Old = MI->second; |
| MDNode *New = MapMetadata(Old, VMap, Flags, TypeMapper, Materializer); |
| if (New != Old) |
| I->setMetadata(MI->first, New); |
| } |
| |
| if (!TypeMapper) |
| return; |
| |
| // If the instruction's type is being remapped, do so now. |
| if (auto CS = CallSite(I)) { |
| SmallVector<Type *, 3> Tys; |
| FunctionType *FTy = CS.getFunctionType(); |
| Tys.reserve(FTy->getNumParams()); |
| for (Type *Ty : FTy->params()) |
| Tys.push_back(TypeMapper->remapType(Ty)); |
| CS.mutateFunctionType(FunctionType::get( |
| TypeMapper->remapType(I->getType()), Tys, FTy->isVarArg())); |
| return; |
| } |
| if (auto *AI = dyn_cast<AllocaInst>(I)) |
| AI->setAllocatedType(TypeMapper->remapType(AI->getAllocatedType())); |
| if (auto *GEP = dyn_cast<GetElementPtrInst>(I)) { |
| GEP->setSourceElementType( |
| TypeMapper->remapType(GEP->getSourceElementType())); |
| GEP->setResultElementType( |
| TypeMapper->remapType(GEP->getResultElementType())); |
| } |
| I->mutateType(TypeMapper->remapType(I->getType())); |
| } |
