1 //===---- llvm/MDBuilder.cpp - Builder for LLVM metadata ------------------===// 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 MDBuilder class, which is used as a convenient way to 11 // create LLVM metadata with a consistent and simplified interface. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "llvm/IR/MDBuilder.h" 16 #include "llvm/IR/Constants.h" 17 #include "llvm/IR/Metadata.h" 18 using namespace llvm; 19 20 MDString *MDBuilder::createString(StringRef Str) { 21 return MDString::get(Context, Str); 22 } 23 24 ConstantAsMetadata *MDBuilder::createConstant(Constant *C) { 25 return ConstantAsMetadata::get(C); 26 } 27 28 MDNode *MDBuilder::createFPMath(float Accuracy) { 29 if (Accuracy == 0.0) 30 return nullptr; 31 assert(Accuracy > 0.0 && "Invalid fpmath accuracy!"); 32 auto *Op = 33 createConstant(ConstantFP::get(Type::getFloatTy(Context), Accuracy)); 34 return MDNode::get(Context, Op); 35 } 36 37 MDNode *MDBuilder::createBranchWeights(uint32_t TrueWeight, 38 uint32_t FalseWeight) { 39 uint32_t Weights[] = {TrueWeight, FalseWeight}; 40 return createBranchWeights(Weights); 41 } 42 43 MDNode *MDBuilder::createBranchWeights(ArrayRef<uint32_t> Weights) { 44 assert(Weights.size() >= 2 && "Need at least two branch weights!"); 45 46 SmallVector<Metadata *, 4> Vals(Weights.size() + 1); 47 Vals[0] = createString("branch_weights"); 48 49 Type *Int32Ty = Type::getInt32Ty(Context); 50 for (unsigned i = 0, e = Weights.size(); i != e; ++i) 51 Vals[i + 1] = createConstant(ConstantInt::get(Int32Ty, Weights[i])); 52 53 return MDNode::get(Context, Vals); 54 } 55 56 MDNode *MDBuilder::createRange(const APInt &Lo, const APInt &Hi) { 57 assert(Lo.getBitWidth() == Hi.getBitWidth() && "Mismatched bitwidths!"); 58 59 Type *Ty = IntegerType::get(Context, Lo.getBitWidth()); 60 return createRange(ConstantInt::get(Ty, Lo), ConstantInt::get(Ty, Hi)); 61 } 62 63 MDNode *MDBuilder::createRange(Constant *Lo, Constant *Hi) { 64 // If the range is everything then it is useless. 65 if (Hi == Lo) 66 return nullptr; 67 68 // Return the range [Lo, Hi). 69 Metadata *Range[2] = {createConstant(Lo), createConstant(Hi)}; 70 return MDNode::get(Context, Range); 71 } 72 73 MDNode *MDBuilder::createAnonymousAARoot(StringRef Name, MDNode *Extra) { 74 // To ensure uniqueness the root node is self-referential. 75 auto Dummy = MDNode::getTemporary(Context, None); 76 77 SmallVector<Metadata *, 3> Args(1, Dummy.get()); 78 if (Extra) 79 Args.push_back(Extra); 80 if (!Name.empty()) 81 Args.push_back(createString(Name)); 82 MDNode *Root = MDNode::get(Context, Args); 83 84 // At this point we have 85 // !0 = metadata !{} <- dummy 86 // !1 = metadata !{metadata !0} <- root 87 // Replace the dummy operand with the root node itself and delete the dummy. 88 Root->replaceOperandWith(0, Root); 89 90 // We now have 91 // !1 = metadata !{metadata !1} <- self-referential root 92 return Root; 93 } 94 95 MDNode *MDBuilder::createTBAARoot(StringRef Name) { 96 return MDNode::get(Context, createString(Name)); 97 } 98 99 /// \brief Return metadata for a non-root TBAA node with the given name, 100 /// parent in the TBAA tree, and value for 'pointsToConstantMemory'. 101 MDNode *MDBuilder::createTBAANode(StringRef Name, MDNode *Parent, 102 bool isConstant) { 103 if (isConstant) { 104 Constant *Flags = ConstantInt::get(Type::getInt64Ty(Context), 1); 105 Metadata *Ops[3] = {createString(Name), Parent, createConstant(Flags)}; 106 return MDNode::get(Context, Ops); 107 } else { 108 Metadata *Ops[2] = {createString(Name), Parent}; 109 return MDNode::get(Context, Ops); 110 } 111 } 112 113 MDNode *MDBuilder::createAliasScopeDomain(StringRef Name) { 114 return MDNode::get(Context, createString(Name)); 115 } 116 117 MDNode *MDBuilder::createAliasScope(StringRef Name, MDNode *Domain) { 118 Metadata *Ops[2] = {createString(Name), Domain}; 119 return MDNode::get(Context, Ops); 120 } 121 122 /// \brief Return metadata for a tbaa.struct node with the given 123 /// struct field descriptions. 124 MDNode *MDBuilder::createTBAAStructNode(ArrayRef<TBAAStructField> Fields) { 125 SmallVector<Metadata *, 4> Vals(Fields.size() * 3); 126 Type *Int64 = Type::getInt64Ty(Context); 127 for (unsigned i = 0, e = Fields.size(); i != e; ++i) { 128 Vals[i * 3 + 0] = createConstant(ConstantInt::get(Int64, Fields[i].Offset)); 129 Vals[i * 3 + 1] = createConstant(ConstantInt::get(Int64, Fields[i].Size)); 130 Vals[i * 3 + 2] = Fields[i].TBAA; 131 } 132 return MDNode::get(Context, Vals); 133 } 134 135 /// \brief Return metadata for a TBAA struct node in the type DAG 136 /// with the given name, a list of pairs (offset, field type in the type DAG). 137 MDNode *MDBuilder::createTBAAStructTypeNode( 138 StringRef Name, ArrayRef<std::pair<MDNode *, uint64_t>> Fields) { 139 SmallVector<Metadata *, 4> Ops(Fields.size() * 2 + 1); 140 Type *Int64 = Type::getInt64Ty(Context); 141 Ops[0] = createString(Name); 142 for (unsigned i = 0, e = Fields.size(); i != e; ++i) { 143 Ops[i * 2 + 1] = Fields[i].first; 144 Ops[i * 2 + 2] = createConstant(ConstantInt::get(Int64, Fields[i].second)); 145 } 146 return MDNode::get(Context, Ops); 147 } 148 149 /// \brief Return metadata for a TBAA scalar type node with the 150 /// given name, an offset and a parent in the TBAA type DAG. 151 MDNode *MDBuilder::createTBAAScalarTypeNode(StringRef Name, MDNode *Parent, 152 uint64_t Offset) { 153 ConstantInt *Off = ConstantInt::get(Type::getInt64Ty(Context), Offset); 154 Metadata *Ops[3] = {createString(Name), Parent, createConstant(Off)}; 155 return MDNode::get(Context, Ops); 156 } 157 158 /// \brief Return metadata for a TBAA tag node with the given 159 /// base type, access type and offset relative to the base type. 160 MDNode *MDBuilder::createTBAAStructTagNode(MDNode *BaseType, MDNode *AccessType, 161 uint64_t Offset) { 162 Type *Int64 = Type::getInt64Ty(Context); 163 Metadata *Ops[3] = {BaseType, AccessType, 164 createConstant(ConstantInt::get(Int64, Offset))}; 165 return MDNode::get(Context, Ops); 166 } 167
