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//===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file defines the MapValue function, which is shared by various parts of
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// the lib/Transforms/Utils library.
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//===----------------------------------------------------------------------===//
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#include "llvm/Transforms/Utils/ValueMapper.h"
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#include "llvm/Type.h"
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#include "llvm/Constants.h"
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#include "llvm/Function.h"
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#include "llvm/Metadata.h"
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#include "llvm/ADT/SmallVector.h"
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Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM,
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bool ModuleLevelChanges) {
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Value *&VMSlot = VM[V];
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if (VMSlot) return VMSlot; // Does it exist in the map yet?
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// NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
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// DenseMap. This includes any recursive calls to MapValue.
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// Global values do not need to be seeded into the VM if they
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// are using the identity mapping.
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if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MDString>(V) ||
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(isa<MDNode>(V) && !cast<MDNode>(V)->isFunctionLocal() &&
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return VMSlot = const_cast<Value*>(V);
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if (const MDNode *MD = dyn_cast<MDNode>(V)) {
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// Start by assuming that we'll use the identity mapping.
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VMSlot = const_cast<Value*>(V);
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// Check all operands to see if any need to be remapped.
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for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i) {
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Value *OP = MD->getOperand(i);
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if (!OP || MapValue(OP, VM, ModuleLevelChanges) == OP) continue;
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// Ok, at least one operand needs remapping.
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MDNode *Dummy = MDNode::getTemporary(V->getContext(), 0, 0);
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SmallVector<Value*, 4> Elts;
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Elts.reserve(MD->getNumOperands());
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for (i = 0; i != e; ++i)
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Elts.push_back(MD->getOperand(i) ?
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MapValue(MD->getOperand(i), VM, ModuleLevelChanges) : 0);
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MDNode *NewMD = MDNode::get(V->getContext(), Elts.data(), Elts.size());
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Dummy->replaceAllUsesWith(NewMD);
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MDNode::deleteTemporary(Dummy);
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// No operands needed remapping; keep the identity map.
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return const_cast<Value*>(V);
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Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V));
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if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
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isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
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return VMSlot = C; // Primitive constants map directly
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if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
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for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
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Value *MV = MapValue(*i, VM, ModuleLevelChanges);
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// This array must contain a reference to a global, make a new array
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std::vector<Constant*> Values;
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Values.reserve(CA->getNumOperands());
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for (User::op_iterator j = b; j != i; ++j)
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Values.push_back(cast<Constant>(*j));
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Values.push_back(cast<Constant>(MV));
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for (++i; i != e; ++i)
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Values.push_back(cast<Constant>(MapValue(*i, VM,
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ModuleLevelChanges)));
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return VM[V] = ConstantArray::get(CA->getType(), Values);
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if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
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for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
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Value *MV = MapValue(*i, VM, ModuleLevelChanges);
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// This struct must contain a reference to a global, make a new struct
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std::vector<Constant*> Values;
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Values.reserve(CS->getNumOperands());
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for (User::op_iterator j = b; j != i; ++j)
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Values.push_back(cast<Constant>(*j));
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Values.push_back(cast<Constant>(MV));
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for (++i; i != e; ++i)
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Values.push_back(cast<Constant>(MapValue(*i, VM,
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ModuleLevelChanges)));
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return VM[V] = ConstantStruct::get(CS->getType(), Values);
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if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
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std::vector<Constant*> Ops;
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for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
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Ops.push_back(cast<Constant>(MapValue(*i, VM, ModuleLevelChanges)));
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return VM[V] = CE->getWithOperands(Ops);
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if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
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for (User::op_iterator b = CV->op_begin(), i = b, e = CV->op_end();
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Value *MV = MapValue(*i, VM, ModuleLevelChanges);
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// This vector value must contain a reference to a global, make a new
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// vector constant and return it.
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std::vector<Constant*> Values;
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Values.reserve(CV->getNumOperands());
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for (User::op_iterator j = b; j != i; ++j)
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Values.push_back(cast<Constant>(*j));
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Values.push_back(cast<Constant>(MV));
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for (++i; i != e; ++i)
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Values.push_back(cast<Constant>(MapValue(*i, VM,
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ModuleLevelChanges)));
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return VM[V] = ConstantVector::get(Values);
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BlockAddress *BA = cast<BlockAddress>(C);
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Function *F = cast<Function>(MapValue(BA->getFunction(), VM,
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ModuleLevelChanges));
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BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM,
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ModuleLevelChanges));
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return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
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/// RemapInstruction - Convert the instruction operands from referencing the
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/// current values into those specified by VMap.
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void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap,
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bool ModuleLevelChanges) {
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for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
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Value *V = MapValue(*op, VMap, ModuleLevelChanges);
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assert(V && "Referenced value not in value map!");
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// Remap attached metadata.
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SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
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I->getAllMetadata(MDs);
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for (SmallVectorImpl<std::pair<unsigned, MDNode *> >::iterator
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MI = MDs.begin(), ME = MDs.end(); MI != ME; ++MI) {
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Value *Old = MI->second;
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Value *New = MapValue(Old, VMap, ModuleLevelChanges);
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I->setMetadata(MI->first, cast<MDNode>(New));