1 //===---- llvm/MDBuilder.cpp - Builder for LLVM metadata ------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file defines the MDBuilder class, which is used as a convenient way to 10 // create LLVM metadata with a consistent and simplified interface. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/IR/MDBuilder.h" 15 #include "llvm/IR/Constants.h" 16 #include "llvm/IR/Function.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 return createBranchWeights({TrueWeight, FalseWeight}); 40 } 41 42 MDNode *MDBuilder::createBranchWeights(ArrayRef<uint32_t> Weights) { 43 assert(Weights.size() >= 1 && "Need at least one branch weights!"); 44 45 SmallVector<Metadata *, 4> Vals(Weights.size() + 1); 46 Vals[0] = createString("branch_weights"); 47 48 Type *Int32Ty = Type::getInt32Ty(Context); 49 for (unsigned i = 0, e = Weights.size(); i != e; ++i) 50 Vals[i + 1] = createConstant(ConstantInt::get(Int32Ty, Weights[i])); 51 52 return MDNode::get(Context, Vals); 53 } 54 55 MDNode *MDBuilder::createUnpredictable() { 56 return MDNode::get(Context, None); 57 } 58 59 MDNode *MDBuilder::createFunctionEntryCount( 60 uint64_t Count, bool Synthetic, 61 const DenseSet<GlobalValue::GUID> *Imports) { 62 Type *Int64Ty = Type::getInt64Ty(Context); 63 SmallVector<Metadata *, 8> Ops; 64 if (Synthetic) 65 Ops.push_back(createString("synthetic_function_entry_count")); 66 else 67 Ops.push_back(createString("function_entry_count")); 68 Ops.push_back(createConstant(ConstantInt::get(Int64Ty, Count))); 69 if (Imports) { 70 SmallVector<GlobalValue::GUID, 2> OrderID(Imports->begin(), Imports->end()); 71 llvm::sort(OrderID); 72 for (auto ID : OrderID) 73 Ops.push_back(createConstant(ConstantInt::get(Int64Ty, ID))); 74 } 75 return MDNode::get(Context, Ops); 76 } 77 78 MDNode *MDBuilder::createFunctionSectionPrefix(StringRef Prefix) { 79 return MDNode::get(Context, 80 {createString("function_section_prefix"), 81 createString(Prefix)}); 82 } 83 84 MDNode *MDBuilder::createRange(const APInt &Lo, const APInt &Hi) { 85 assert(Lo.getBitWidth() == Hi.getBitWidth() && "Mismatched bitwidths!"); 86 87 Type *Ty = IntegerType::get(Context, Lo.getBitWidth()); 88 return createRange(ConstantInt::get(Ty, Lo), ConstantInt::get(Ty, Hi)); 89 } 90 91 MDNode *MDBuilder::createRange(Constant *Lo, Constant *Hi) { 92 // If the range is everything then it is useless. 93 if (Hi == Lo) 94 return nullptr; 95 96 // Return the range [Lo, Hi). 97 return MDNode::get(Context, {createConstant(Lo), createConstant(Hi)}); 98 } 99 100 MDNode *MDBuilder::createCallees(ArrayRef<Function *> Callees) { 101 SmallVector<Metadata *, 4> Ops; 102 for (Function *F : Callees) 103 Ops.push_back(createConstant(F)); 104 return MDNode::get(Context, Ops); 105 } 106 107 MDNode *MDBuilder::createCallbackEncoding(unsigned CalleeArgNo, 108 ArrayRef<int> Arguments, 109 bool VarArgArePassed) { 110 SmallVector<Metadata *, 4> Ops; 111 112 Type *Int64 = Type::getInt64Ty(Context); 113 Ops.push_back(createConstant(ConstantInt::get(Int64, CalleeArgNo))); 114 115 for (int ArgNo : Arguments) 116 Ops.push_back(createConstant(ConstantInt::get(Int64, ArgNo, true))); 117 118 Type *Int1 = Type::getInt1Ty(Context); 119 Ops.push_back(createConstant(ConstantInt::get(Int1, VarArgArePassed))); 120 121 return MDNode::get(Context, Ops); 122 } 123 124 MDNode *MDBuilder::mergeCallbackEncodings(MDNode *ExistingCallbacks, 125 MDNode *NewCB) { 126 if (!ExistingCallbacks) 127 return MDNode::get(Context, {NewCB}); 128 129 auto *NewCBCalleeIdxAsCM = cast<ConstantAsMetadata>(NewCB->getOperand(0)); 130 uint64_t NewCBCalleeIdx = 131 cast<ConstantInt>(NewCBCalleeIdxAsCM->getValue())->getZExtValue(); 132 (void)NewCBCalleeIdx; 133 134 SmallVector<Metadata *, 4> Ops; 135 unsigned NumExistingOps = ExistingCallbacks->getNumOperands(); 136 Ops.resize(NumExistingOps + 1); 137 138 for (unsigned u = 0; u < NumExistingOps; u++) { 139 Ops[u] = ExistingCallbacks->getOperand(u); 140 141 auto *OldCBCalleeIdxAsCM = cast<ConstantAsMetadata>(Ops[u]); 142 uint64_t OldCBCalleeIdx = 143 cast<ConstantInt>(OldCBCalleeIdxAsCM->getValue())->getZExtValue(); 144 (void)OldCBCalleeIdx; 145 assert(NewCBCalleeIdx != OldCBCalleeIdx && 146 "Cannot map a callback callee index twice!"); 147 } 148 149 Ops[NumExistingOps] = NewCB; 150 return MDNode::get(Context, Ops); 151 } 152 153 MDNode *MDBuilder::createAnonymousAARoot(StringRef Name, MDNode *Extra) { 154 SmallVector<Metadata *, 3> Args(1, nullptr); 155 if (Extra) 156 Args.push_back(Extra); 157 if (!Name.empty()) 158 Args.push_back(createString(Name)); 159 MDNode *Root = MDNode::getDistinct(Context, Args); 160 161 // At this point we have 162 // !0 = distinct !{null} <- root 163 // Replace the reserved operand with the root node itself. 164 Root->replaceOperandWith(0, Root); 165 166 // We now have 167 // !0 = distinct !{!0} <- root 168 return Root; 169 } 170 171 MDNode *MDBuilder::createTBAARoot(StringRef Name) { 172 return MDNode::get(Context, createString(Name)); 173 } 174 175 /// Return metadata for a non-root TBAA node with the given name, 176 /// parent in the TBAA tree, and value for 'pointsToConstantMemory'. 177 MDNode *MDBuilder::createTBAANode(StringRef Name, MDNode *Parent, 178 bool isConstant) { 179 if (isConstant) { 180 Constant *Flags = ConstantInt::get(Type::getInt64Ty(Context), 1); 181 return MDNode::get(Context, 182 {createString(Name), Parent, createConstant(Flags)}); 183 } 184 return MDNode::get(Context, {createString(Name), Parent}); 185 } 186 187 MDNode *MDBuilder::createAliasScopeDomain(StringRef Name) { 188 return MDNode::get(Context, createString(Name)); 189 } 190 191 MDNode *MDBuilder::createAliasScope(StringRef Name, MDNode *Domain) { 192 return MDNode::get(Context, {createString(Name), Domain}); 193 } 194 195 /// Return metadata for a tbaa.struct node with the given 196 /// struct field descriptions. 197 MDNode *MDBuilder::createTBAAStructNode(ArrayRef<TBAAStructField> Fields) { 198 SmallVector<Metadata *, 4> Vals(Fields.size() * 3); 199 Type *Int64 = Type::getInt64Ty(Context); 200 for (unsigned i = 0, e = Fields.size(); i != e; ++i) { 201 Vals[i * 3 + 0] = createConstant(ConstantInt::get(Int64, Fields[i].Offset)); 202 Vals[i * 3 + 1] = createConstant(ConstantInt::get(Int64, Fields[i].Size)); 203 Vals[i * 3 + 2] = Fields[i].Type; 204 } 205 return MDNode::get(Context, Vals); 206 } 207 208 /// Return metadata for a TBAA struct node in the type DAG 209 /// with the given name, a list of pairs (offset, field type in the type DAG). 210 MDNode *MDBuilder::createTBAAStructTypeNode( 211 StringRef Name, ArrayRef<std::pair<MDNode *, uint64_t>> Fields) { 212 SmallVector<Metadata *, 4> Ops(Fields.size() * 2 + 1); 213 Type *Int64 = Type::getInt64Ty(Context); 214 Ops[0] = createString(Name); 215 for (unsigned i = 0, e = Fields.size(); i != e; ++i) { 216 Ops[i * 2 + 1] = Fields[i].first; 217 Ops[i * 2 + 2] = createConstant(ConstantInt::get(Int64, Fields[i].second)); 218 } 219 return MDNode::get(Context, Ops); 220 } 221 222 /// Return metadata for a TBAA scalar type node with the 223 /// given name, an offset and a parent in the TBAA type DAG. 224 MDNode *MDBuilder::createTBAAScalarTypeNode(StringRef Name, MDNode *Parent, 225 uint64_t Offset) { 226 ConstantInt *Off = ConstantInt::get(Type::getInt64Ty(Context), Offset); 227 return MDNode::get(Context, 228 {createString(Name), Parent, createConstant(Off)}); 229 } 230 231 /// Return metadata for a TBAA tag node with the given 232 /// base type, access type and offset relative to the base type. 233 MDNode *MDBuilder::createTBAAStructTagNode(MDNode *BaseType, MDNode *AccessType, 234 uint64_t Offset, bool IsConstant) { 235 IntegerType *Int64 = Type::getInt64Ty(Context); 236 ConstantInt *Off = ConstantInt::get(Int64, Offset); 237 if (IsConstant) { 238 return MDNode::get(Context, {BaseType, AccessType, createConstant(Off), 239 createConstant(ConstantInt::get(Int64, 1))}); 240 } 241 return MDNode::get(Context, {BaseType, AccessType, createConstant(Off)}); 242 } 243 244 MDNode *MDBuilder::createTBAATypeNode(MDNode *Parent, uint64_t Size, 245 Metadata *Id, 246 ArrayRef<TBAAStructField> Fields) { 247 SmallVector<Metadata *, 4> Ops(3 + Fields.size() * 3); 248 Type *Int64 = Type::getInt64Ty(Context); 249 Ops[0] = Parent; 250 Ops[1] = createConstant(ConstantInt::get(Int64, Size)); 251 Ops[2] = Id; 252 for (unsigned I = 0, E = Fields.size(); I != E; ++I) { 253 Ops[I * 3 + 3] = Fields[I].Type; 254 Ops[I * 3 + 4] = createConstant(ConstantInt::get(Int64, Fields[I].Offset)); 255 Ops[I * 3 + 5] = createConstant(ConstantInt::get(Int64, Fields[I].Size)); 256 } 257 return MDNode::get(Context, Ops); 258 } 259 260 MDNode *MDBuilder::createTBAAAccessTag(MDNode *BaseType, MDNode *AccessType, 261 uint64_t Offset, uint64_t Size, 262 bool IsImmutable) { 263 IntegerType *Int64 = Type::getInt64Ty(Context); 264 auto *OffsetNode = createConstant(ConstantInt::get(Int64, Offset)); 265 auto *SizeNode = createConstant(ConstantInt::get(Int64, Size)); 266 if (IsImmutable) { 267 auto *ImmutabilityFlagNode = createConstant(ConstantInt::get(Int64, 1)); 268 return MDNode::get(Context, {BaseType, AccessType, OffsetNode, SizeNode, 269 ImmutabilityFlagNode}); 270 } 271 return MDNode::get(Context, {BaseType, AccessType, OffsetNode, SizeNode}); 272 } 273 274 MDNode *MDBuilder::createMutableTBAAAccessTag(MDNode *Tag) { 275 MDNode *BaseType = cast<MDNode>(Tag->getOperand(0)); 276 MDNode *AccessType = cast<MDNode>(Tag->getOperand(1)); 277 Metadata *OffsetNode = Tag->getOperand(2); 278 uint64_t Offset = mdconst::extract<ConstantInt>(OffsetNode)->getZExtValue(); 279 280 bool NewFormat = isa<MDNode>(AccessType->getOperand(0)); 281 282 // See if the tag is already mutable. 283 unsigned ImmutabilityFlagOp = NewFormat ? 4 : 3; 284 if (Tag->getNumOperands() <= ImmutabilityFlagOp) 285 return Tag; 286 287 // If Tag is already mutable then return it. 288 Metadata *ImmutabilityFlagNode = Tag->getOperand(ImmutabilityFlagOp); 289 if (!mdconst::extract<ConstantInt>(ImmutabilityFlagNode)->getValue()) 290 return Tag; 291 292 // Otherwise, create another node. 293 if (!NewFormat) 294 return createTBAAStructTagNode(BaseType, AccessType, Offset); 295 296 Metadata *SizeNode = Tag->getOperand(3); 297 uint64_t Size = mdconst::extract<ConstantInt>(SizeNode)->getZExtValue(); 298 return createTBAAAccessTag(BaseType, AccessType, Offset, Size); 299 } 300 301 MDNode *MDBuilder::createIrrLoopHeaderWeight(uint64_t Weight) { 302 Metadata *Vals[] = { 303 createString("loop_header_weight"), 304 createConstant(ConstantInt::get(Type::getInt64Ty(Context), Weight)), 305 }; 306 return MDNode::get(Context, Vals); 307 } 308 309 MDNode *MDBuilder::createPseudoProbeDesc(uint64_t GUID, uint64_t Hash, 310 Function *F) { 311 auto *Int64Ty = Type::getInt64Ty(Context); 312 SmallVector<Metadata *, 3> Ops(3); 313 Ops[0] = createConstant(ConstantInt::get(Int64Ty, GUID)); 314 Ops[1] = createConstant(ConstantInt::get(Int64Ty, Hash)); 315 Ops[2] = createString(F->getName()); 316 return MDNode::get(Context, Ops); 317 } 318