llvm/lib/IR/MDBuilder.cpp

   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 }