//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/ValueMapper.h"
-#include "llvm/Type.h"
-#include "llvm/Constants.h"
-#include "llvm/Function.h"
-#include "llvm/Metadata.h"
-#include "llvm/ADT/SmallVector.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"
+#include "llvm/IR/Operator.h"
using namespace llvm;
-Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM,
- bool ModuleLevelChanges) {
- TrackingVH<Value> &VMSlot = VM[V];
- if (VMSlot) return VMSlot; // Does it exist in the map yet?
+// 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;
- // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
- // DenseMap. This includes any recursive calls to MapValue.
+ // 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) || isa<InlineAsm>(V) || isa<MDString>(V) ||
- (isa<MDNode>(V) && !cast<MDNode>(V)->isFunctionLocal() &&
- !ModuleLevelChanges))
- return VMSlot = const_cast<Value*>(V);
-
- if (const MDNode *MD = dyn_cast<MDNode>(V)) {
- // Start by assuming that we'll use the identity mapping.
- VMSlot = const_cast<Value*>(V);
-
- // Check all operands to see if any need to be remapped.
- for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i) {
- Value *OP = MD->getOperand(i);
- if (!OP || MapValue(OP, VM, ModuleLevelChanges) == OP) continue;
-
- // Ok, at least one operand needs remapping.
- MDNode *Dummy = MDNode::getTemporary(V->getContext(), 0, 0);
- VM[V] = Dummy;
- SmallVector<Value*, 4> Elts;
- Elts.reserve(MD->getNumOperands());
- for (i = 0; i != e; ++i)
- Elts.push_back(MD->getOperand(i) ?
- MapValue(MD->getOperand(i), VM, ModuleLevelChanges) : 0);
- MDNode *NewMD = MDNode::get(V->getContext(), Elts.data(), Elts.size());
- Dummy->replaceAllUsesWith(NewMD);
- MDNode::deleteTemporary(Dummy);
- return VM[V] = NewMD;
+ if (isa<GlobalValue>(V)) {
+ if (Flags & RF_NullMapMissingGlobalValues) {
+ assert(!(Flags & RF_IgnoreMissingEntries) &&
+ "Illegal to specify both RF_NullMapMissingGlobalValues and "
+ "RF_IgnoreMissingEntries");
+ return nullptr;
+ }
+ 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);
- // No operands needed remapping; keep the identity map.
- return 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 || (Flags & RF_NullMapMissingGlobalValues)) &&
+ // "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 == 0)
- return 0;
+ if (!C)
+ return nullptr;
- if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
- isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
- isa<UndefValue>(C))
- return VMSlot = C; // Primitive constants map directly
+ 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());
+ }
- if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
- for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
- i != e; ++i) {
- Value *MV = MapValue(*i, VM, ModuleLevelChanges);
- if (MV != *i) {
- // This array must contain a reference to a global, make a new array
- // and return it.
- //
- std::vector<Constant*> Values;
- Values.reserve(CA->getNumOperands());
- for (User::op_iterator j = b; j != i; ++j)
- Values.push_back(cast<Constant>(*j));
- Values.push_back(cast<Constant>(MV));
- for (++i; i != e; ++i)
- Values.push_back(cast<Constant>(MapValue(*i, VM,
- ModuleLevelChanges)));
- return VM[V] = ConstantArray::get(CA->getType(), Values);
- }
- }
- return VM[V] = C;
+ // 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;
}
- if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
- for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
- i != e; ++i) {
- Value *MV = MapValue(*i, VM, ModuleLevelChanges);
- if (MV != *i) {
- // This struct must contain a reference to a global, make a new struct
- // and return it.
- //
- std::vector<Constant*> Values;
- Values.reserve(CS->getNumOperands());
- for (User::op_iterator j = b; j != i; ++j)
- Values.push_back(cast<Constant>(*j));
- Values.push_back(cast<Constant>(MV));
- for (++i; i != e; ++i)
- Values.push_back(cast<Constant>(MapValue(*i, VM,
- ModuleLevelChanges)));
- return VM[V] = ConstantStruct::get(CS->getType(), Values);
- }
- }
+ // 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;
- }
- if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
- std::vector<Constant*> Ops;
- for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
- Ops.push_back(cast<Constant>(MapValue(*i, VM, ModuleLevelChanges)));
- return VM[V] = CE->getWithOperands(Ops);
- }
+ // 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));
- if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
- for (User::op_iterator b = CV->op_begin(), i = b, e = CV->op_end();
- i != e; ++i) {
- Value *MV = MapValue(*i, VM, ModuleLevelChanges);
- if (MV != *i) {
- // This vector value must contain a reference to a global, make a new
- // vector constant and return it.
- //
- std::vector<Constant*> Values;
- Values.reserve(CV->getNumOperands());
- for (User::op_iterator j = b; j != i; ++j)
- Values.push_back(cast<Constant>(*j));
- Values.push_back(cast<Constant>(MV));
- for (++i; i != e; ++i)
- Values.push_back(cast<Constant>(MapValue(*i, VM,
- ModuleLevelChanges)));
- return VM[V] = ConstantVector::get(Values);
- }
+ // 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));
+ }
+ Type *NewSrcTy = nullptr;
+ if (TypeMapper)
+ if (auto *GEPO = dyn_cast<GEPOperator>(C))
+ NewSrcTy = TypeMapper->remapType(GEPO->getSourceElementType());
+
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
+ return VM[V] = CE->getWithOperands(Ops, NewTy, false, NewSrcTy);
+ 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 *> &DistinctWorklist,
+ ValueToValueMapTy &VM, RemapFlags Flags,
+ ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer);
+
+static Metadata *mapMetadataOp(Metadata *Op,
+ SmallVectorImpl<MDNode *> &DistinctWorklist,
+ ValueToValueMapTy &VM, RemapFlags Flags,
+ ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer) {
+ if (!Op)
+ return nullptr;
+ if (Metadata *MappedOp = MapMetadataImpl(Op, DistinctWorklist, 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.
+ //
+ // assert((Flags & RF_NullMapMissingGlobalValues) &&
+ // "Referenced metadata not in value map!");
+ return nullptr;
+}
+
+/// Resolve uniquing cycles involving the given metadata.
+static void resolveCycles(Metadata *MD) {
+ if (auto *N = dyn_cast_or_null<MDNode>(MD))
+ if (!N->isResolved())
+ N->resolveCycles();
+}
+
+/// Remap the operands of an MDNode.
+///
+/// If \c Node is temporary, uniquing cycles are ignored. If \c Node is
+/// distinct, uniquing cycles are resolved as they're found.
+///
+/// \pre \c Node.isDistinct() or \c Node.isTemporary().
+static bool remapOperands(MDNode &Node,
+ SmallVectorImpl<MDNode *> &DistinctWorklist,
+ ValueToValueMapTy &VM, RemapFlags Flags,
+ ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer) {
+ assert(!Node.isUniqued() && "Expected temporary or distinct node");
+ const bool IsDistinct = Node.isDistinct();
+
+ bool AnyChanged = false;
+ for (unsigned I = 0, E = Node.getNumOperands(); I != E; ++I) {
+ Metadata *Old = Node.getOperand(I);
+ Metadata *New = mapMetadataOp(Old, DistinctWorklist, VM, Flags, TypeMapper,
+ Materializer);
+ if (Old != New) {
+ AnyChanged = true;
+ Node.replaceOperandWith(I, New);
+
+ // Resolve uniquing cycles underneath distinct nodes on the fly so they
+ // don't infect later operands.
+ if (IsDistinct)
+ resolveCycles(New);
}
- return VM[V] = C;
}
-
- BlockAddress *BA = cast<BlockAddress>(C);
- Function *F = cast<Function>(MapValue(BA->getFunction(), VM,
- ModuleLevelChanges));
- BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM,
- ModuleLevelChanges));
- return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
+
+ return AnyChanged;
+}
+
+/// Map a distinct MDNode.
+///
+/// Whether distinct nodes change is independent of their operands. If \a
+/// RF_MoveDistinctMDs, then they are reused, and their operands remapped in
+/// place; effectively, they're moved from one graph to another. Otherwise,
+/// they're cloned/duplicated, and the new copy's operands are remapped.
+static Metadata *mapDistinctNode(const MDNode *Node,
+ SmallVectorImpl<MDNode *> &DistinctWorklist,
+ ValueToValueMapTy &VM, RemapFlags Flags,
+ ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer) {
+ assert(Node->isDistinct() && "Expected distinct node");
+
+ MDNode *NewMD;
+ if (Flags & RF_MoveDistinctMDs)
+ NewMD = const_cast<MDNode *>(Node);
+ else
+ NewMD = MDNode::replaceWithDistinct(Node->clone());
+
+ // Remap operands later.
+ DistinctWorklist.push_back(NewMD);
+ return mapToMetadata(VM, Node, 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 *> &DistinctWorklist,
+ ValueToValueMapTy &VM, RemapFlags Flags,
+ ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer) {
+ assert(Node->isUniqued() && "Expected uniqued node");
+
+ // Create a temporary node and map it upfront in case we have a uniquing
+ // cycle. If necessary, this mapping will get updated by RAUW logic before
+ // returning.
+ auto ClonedMD = Node->clone();
+ mapToMetadata(VM, Node, ClonedMD.get());
+ if (!remapOperands(*ClonedMD, DistinctWorklist, VM, Flags, TypeMapper,
+ Materializer)) {
+ // No operands changed, so use the original.
+ ClonedMD->replaceAllUsesWith(const_cast<MDNode *>(Node));
+ return const_cast<MDNode *>(Node);
+ }
+
+ // Uniquify the cloned node.
+ return MDNode::replaceWithUniqued(std::move(ClonedMD));
+}
+
+static Metadata *MapMetadataImpl(const Metadata *MD,
+ SmallVectorImpl<MDNode *> &DistinctWorklist,
+ 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 || (Flags & RF_NullMapMissingGlobalValues)) &&
+ // "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, DistinctWorklist, VM, Flags, TypeMapper,
+ Materializer);
+
+ return mapUniquedNode(Node, DistinctWorklist, VM, Flags, TypeMapper,
+ Materializer);
+}
+
+Metadata *llvm::MapMetadata(const Metadata *MD, ValueToValueMapTy &VM,
+ RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
+ ValueMaterializer *Materializer) {
+ SmallVector<MDNode *, 8> DistinctWorklist;
+ Metadata *NewMD = MapMetadataImpl(MD, DistinctWorklist, VM, Flags, TypeMapper,
+ Materializer);
+
+ // When there are no module-level changes, it's possible that the metadata
+ // graph has temporaries. Skip the logic to resolve cycles, since it's
+ // unnecessary (and invalid) in that case.
+ if (Flags & RF_NoModuleLevelChanges)
+ return NewMD;
+
+ // Resolve cycles involving the entry metadata.
+ resolveCycles(NewMD);
+
+ // Remap the operands of distinct MDNodes.
+ while (!DistinctWorklist.empty())
+ remapOperands(*DistinctWorklist.pop_back_val(), DistinctWorklist, VM, Flags,
+ TypeMapper, Materializer);
+
+ 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,
- bool ModuleLevelChanges) {
+ 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, ModuleLevelChanges);
- assert(V && "Referenced value not in value map!");
- *op = V;
+ 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) {
- Value *Old = MI->second;
- Value *New = MapValue(Old, VMap, ModuleLevelChanges);
+ for (const auto &MI : MDs) {
+ MDNode *Old = MI.second;
+ MDNode *New = MapMetadata(Old, VMap, Flags, TypeMapper, Materializer);
if (New != Old)
- I->setMetadata(MI->first, cast<MDNode>(New));
+ 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()));
}
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