ValueMapper.cpp revision cd9b49245115f13e2e190fedfdbbbfc19a49b78f
1//===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines the MapValue function, which is shared by various parts of 11// the lib/Transforms/Utils library. 12// 13//===----------------------------------------------------------------------===// 14 15#include "ValueMapper.h" 16#include "llvm/Type.h" 17#include "llvm/Constants.h" 18#include "llvm/Function.h" 19#include "llvm/Metadata.h" 20#include "llvm/ADT/SmallVector.h" 21using namespace llvm; 22 23Value *llvm::MapValue(const Value *V, ValueMapTy &VM) { 24 Value *&VMSlot = VM[V]; 25 if (VMSlot) return VMSlot; // Does it exist in the map yet? 26 27 // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the 28 // DenseMap. This includes any recursive calls to MapValue. 29 30 // Global values and non-function-local metadata do not need to be seeded into 31 // the ValueMap if they are using the identity mapping. 32 if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MDString>(V) || 33 (isa<MDNode>(V) && !cast<MDNode>(V)->isFunctionLocal())) 34 return VMSlot = const_cast<Value*>(V); 35 36 if (const MDNode *MD = dyn_cast<MDNode>(V)) { 37 SmallVector<Value*, 4> Elts; 38 for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i) 39 Elts.push_back(MD->getOperand(i) ? MapValue(MD->getOperand(i), VM) : 0); 40 return VM[V] = MDNode::get(V->getContext(), Elts.data(), Elts.size()); 41 } 42 43 Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V)); 44 if (C == 0) return 0; 45 46 if (isa<ConstantInt>(C) || isa<ConstantFP>(C) || 47 isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) || 48 isa<UndefValue>(C) || isa<MDString>(C)) 49 return VMSlot = C; // Primitive constants map directly 50 51 if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) { 52 for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end(); 53 i != e; ++i) { 54 Value *MV = MapValue(*i, VM); 55 if (MV != *i) { 56 // This array must contain a reference to a global, make a new array 57 // and return it. 58 // 59 std::vector<Constant*> Values; 60 Values.reserve(CA->getNumOperands()); 61 for (User::op_iterator j = b; j != i; ++j) 62 Values.push_back(cast<Constant>(*j)); 63 Values.push_back(cast<Constant>(MV)); 64 for (++i; i != e; ++i) 65 Values.push_back(cast<Constant>(MapValue(*i, VM))); 66 return VM[V] = ConstantArray::get(CA->getType(), Values); 67 } 68 } 69 return VM[V] = C; 70 } 71 72 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) { 73 for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end(); 74 i != e; ++i) { 75 Value *MV = MapValue(*i, VM); 76 if (MV != *i) { 77 // This struct must contain a reference to a global, make a new struct 78 // and return it. 79 // 80 std::vector<Constant*> Values; 81 Values.reserve(CS->getNumOperands()); 82 for (User::op_iterator j = b; j != i; ++j) 83 Values.push_back(cast<Constant>(*j)); 84 Values.push_back(cast<Constant>(MV)); 85 for (++i; i != e; ++i) 86 Values.push_back(cast<Constant>(MapValue(*i, VM))); 87 return VM[V] = ConstantStruct::get(CS->getType(), Values); 88 } 89 } 90 return VM[V] = C; 91 } 92 93 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { 94 std::vector<Constant*> Ops; 95 for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i) 96 Ops.push_back(cast<Constant>(MapValue(*i, VM))); 97 return VM[V] = CE->getWithOperands(Ops); 98 } 99 100 if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) { 101 for (User::op_iterator b = CV->op_begin(), i = b, e = CV->op_end(); 102 i != e; ++i) { 103 Value *MV = MapValue(*i, VM); 104 if (MV != *i) { 105 // This vector value must contain a reference to a global, make a new 106 // vector constant and return it. 107 // 108 std::vector<Constant*> Values; 109 Values.reserve(CV->getNumOperands()); 110 for (User::op_iterator j = b; j != i; ++j) 111 Values.push_back(cast<Constant>(*j)); 112 Values.push_back(cast<Constant>(MV)); 113 for (++i; i != e; ++i) 114 Values.push_back(cast<Constant>(MapValue(*i, VM))); 115 return VM[V] = ConstantVector::get(Values); 116 } 117 } 118 return VM[V] = C; 119 } 120 121 BlockAddress *BA = cast<BlockAddress>(C); 122 Function *F = cast<Function>(MapValue(BA->getFunction(), VM)); 123 BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM)); 124 return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock()); 125} 126 127/// RemapInstruction - Convert the instruction operands from referencing the 128/// current values into those specified by ValueMap. 129/// 130void llvm::RemapInstruction(Instruction *I, ValueMapTy &ValueMap) { 131 for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) { 132 Value *V = MapValue(*op, ValueMap); 133 assert(V && "Referenced value not in value map!"); 134 *op = V; 135 } 136} 137 138