LLVM API Documentation
00001 //===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // This file defines the MapValue function, which is shared by various parts of 00011 // the lib/Transforms/Utils library. 00012 // 00013 //===----------------------------------------------------------------------===// 00014 00015 #include "ValueMapper.h" 00016 #include "llvm/Constants.h" 00017 #include "llvm/GlobalValue.h" 00018 #include "llvm/Instruction.h" 00019 using namespace llvm; 00020 00021 Value *llvm::MapValue(const Value *V, std::map<const Value*, Value*> &VM) { 00022 Value *&VMSlot = VM[V]; 00023 if (VMSlot) return VMSlot; // Does it exist in the map yet? 00024 00025 // Global values do not need to be seeded into the ValueMap if they are using 00026 // the identity mapping. 00027 if (isa<GlobalValue>(V) || isa<InlineAsm>(V)) 00028 return VMSlot = const_cast<Value*>(V); 00029 00030 if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V))) { 00031 if (isa<ConstantIntegral>(C) || isa<ConstantFP>(C) || 00032 isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) || 00033 isa<UndefValue>(C)) 00034 return VMSlot = C; // Primitive constants map directly 00035 else if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) { 00036 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) { 00037 Value *MV = MapValue(CA->getOperand(i), VM); 00038 if (MV != CA->getOperand(i)) { 00039 // This array must contain a reference to a global, make a new array 00040 // and return it. 00041 // 00042 std::vector<Constant*> Values; 00043 Values.reserve(CA->getNumOperands()); 00044 for (unsigned j = 0; j != i; ++j) 00045 Values.push_back(CA->getOperand(j)); 00046 Values.push_back(cast<Constant>(MV)); 00047 for (++i; i != e; ++i) 00048 Values.push_back(cast<Constant>(MapValue(CA->getOperand(i), VM))); 00049 return VMSlot = ConstantArray::get(CA->getType(), Values); 00050 } 00051 } 00052 return VMSlot = C; 00053 00054 } else if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) { 00055 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 00056 Value *MV = MapValue(CS->getOperand(i), VM); 00057 if (MV != CS->getOperand(i)) { 00058 // This struct must contain a reference to a global, make a new struct 00059 // and return it. 00060 // 00061 std::vector<Constant*> Values; 00062 Values.reserve(CS->getNumOperands()); 00063 for (unsigned j = 0; j != i; ++j) 00064 Values.push_back(CS->getOperand(j)); 00065 Values.push_back(cast<Constant>(MV)); 00066 for (++i; i != e; ++i) 00067 Values.push_back(cast<Constant>(MapValue(CS->getOperand(i), VM))); 00068 return VMSlot = ConstantStruct::get(CS->getType(), Values); 00069 } 00070 } 00071 return VMSlot = C; 00072 00073 } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { 00074 std::vector<Constant*> Ops; 00075 for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) 00076 Ops.push_back(cast<Constant>(MapValue(CE->getOperand(i), VM))); 00077 return VMSlot = CE->getWithOperands(Ops); 00078 } else if (ConstantPacked *CP = dyn_cast<ConstantPacked>(C)) { 00079 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) { 00080 Value *MV = MapValue(CP->getOperand(i), VM); 00081 if (MV != CP->getOperand(i)) { 00082 // This packed value must contain a reference to a global, make a new 00083 // packed constant and return it. 00084 // 00085 std::vector<Constant*> Values; 00086 Values.reserve(CP->getNumOperands()); 00087 for (unsigned j = 0; j != i; ++j) 00088 Values.push_back(CP->getOperand(j)); 00089 Values.push_back(cast<Constant>(MV)); 00090 for (++i; i != e; ++i) 00091 Values.push_back(cast<Constant>(MapValue(CP->getOperand(i), VM))); 00092 return VMSlot = ConstantPacked::get(Values); 00093 } 00094 } 00095 return VMSlot = C; 00096 00097 } else { 00098 assert(0 && "Unknown type of constant!"); 00099 } 00100 } 00101 00102 return 0; 00103 } 00104 00105 /// RemapInstruction - Convert the instruction operands from referencing the 00106 /// current values into those specified by ValueMap. 00107 /// 00108 void llvm::RemapInstruction(Instruction *I, 00109 std::map<const Value *, Value*> &ValueMap) { 00110 for (unsigned op = 0, E = I->getNumOperands(); op != E; ++op) { 00111 const Value *Op = I->getOperand(op); 00112 Value *V = MapValue(Op, ValueMap); 00113 assert(V && "Referenced value not in value map!"); 00114 I->setOperand(op, V); 00115 } 00116 }