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"
18using namespace llvm;
19
20MDString *MDBuilder::createString(StringRef Str) {
21  return MDString::get(Context, Str);
22}
23
24ConstantAsMetadata *MDBuilder::createConstant(Constant *C) {
25  return ConstantAsMetadata::get(C);
26}
27
28MDNode *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
37MDNode *MDBuilder::createBranchWeights(uint32_t TrueWeight,
38                                       uint32_t FalseWeight) {
39  return createBranchWeights({TrueWeight, FalseWeight});
40}
41
42MDNode *MDBuilder::createBranchWeights(ArrayRef<uint32_t> Weights) {
43  assert(Weights.size() >= 2 && "Need at least two 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
55MDNode *MDBuilder::createUnpredictable() {
56  return MDNode::get(Context, None);
57}
58
59MDNode *MDBuilder::createFunctionEntryCount(uint64_t Count) {
60  Type *Int64Ty = Type::getInt64Ty(Context);
61  return MDNode::get(Context,
62                     {createString("function_entry_count"),
63                      createConstant(ConstantInt::get(Int64Ty, Count))});
64}
65
66MDNode *MDBuilder::createRange(const APInt &Lo, const APInt &Hi) {
67  assert(Lo.getBitWidth() == Hi.getBitWidth() && "Mismatched bitwidths!");
68
69  Type *Ty = IntegerType::get(Context, Lo.getBitWidth());
70  return createRange(ConstantInt::get(Ty, Lo), ConstantInt::get(Ty, Hi));
71}
72
73MDNode *MDBuilder::createRange(Constant *Lo, Constant *Hi) {
74  // If the range is everything then it is useless.
75  if (Hi == Lo)
76    return nullptr;
77
78  // Return the range [Lo, Hi).
79  return MDNode::get(Context, {createConstant(Lo), createConstant(Hi)});
80}
81
82MDNode *MDBuilder::createAnonymousAARoot(StringRef Name, MDNode *Extra) {
83  // To ensure uniqueness the root node is self-referential.
84  auto Dummy = MDNode::getTemporary(Context, None);
85
86  SmallVector<Metadata *, 3> Args(1, Dummy.get());
87  if (Extra)
88    Args.push_back(Extra);
89  if (!Name.empty())
90    Args.push_back(createString(Name));
91  MDNode *Root = MDNode::get(Context, Args);
92
93  // At this point we have
94  //   !0 = metadata !{}            <- dummy
95  //   !1 = metadata !{metadata !0} <- root
96  // Replace the dummy operand with the root node itself and delete the dummy.
97  Root->replaceOperandWith(0, Root);
98
99  // We now have
100  //   !1 = metadata !{metadata !1} <- self-referential root
101  return Root;
102}
103
104MDNode *MDBuilder::createTBAARoot(StringRef Name) {
105  return MDNode::get(Context, createString(Name));
106}
107
108/// \brief Return metadata for a non-root TBAA node with the given name,
109/// parent in the TBAA tree, and value for 'pointsToConstantMemory'.
110MDNode *MDBuilder::createTBAANode(StringRef Name, MDNode *Parent,
111                                  bool isConstant) {
112  if (isConstant) {
113    Constant *Flags = ConstantInt::get(Type::getInt64Ty(Context), 1);
114    return MDNode::get(Context,
115                       {createString(Name), Parent, createConstant(Flags)});
116  }
117  return MDNode::get(Context, {createString(Name), Parent});
118}
119
120MDNode *MDBuilder::createAliasScopeDomain(StringRef Name) {
121  return MDNode::get(Context, createString(Name));
122}
123
124MDNode *MDBuilder::createAliasScope(StringRef Name, MDNode *Domain) {
125  return MDNode::get(Context, {createString(Name), Domain});
126}
127
128/// \brief Return metadata for a tbaa.struct node with the given
129/// struct field descriptions.
130MDNode *MDBuilder::createTBAAStructNode(ArrayRef<TBAAStructField> Fields) {
131  SmallVector<Metadata *, 4> Vals(Fields.size() * 3);
132  Type *Int64 = Type::getInt64Ty(Context);
133  for (unsigned i = 0, e = Fields.size(); i != e; ++i) {
134    Vals[i * 3 + 0] = createConstant(ConstantInt::get(Int64, Fields[i].Offset));
135    Vals[i * 3 + 1] = createConstant(ConstantInt::get(Int64, Fields[i].Size));
136    Vals[i * 3 + 2] = Fields[i].TBAA;
137  }
138  return MDNode::get(Context, Vals);
139}
140
141/// \brief Return metadata for a TBAA struct node in the type DAG
142/// with the given name, a list of pairs (offset, field type in the type DAG).
143MDNode *MDBuilder::createTBAAStructTypeNode(
144    StringRef Name, ArrayRef<std::pair<MDNode *, uint64_t>> Fields) {
145  SmallVector<Metadata *, 4> Ops(Fields.size() * 2 + 1);
146  Type *Int64 = Type::getInt64Ty(Context);
147  Ops[0] = createString(Name);
148  for (unsigned i = 0, e = Fields.size(); i != e; ++i) {
149    Ops[i * 2 + 1] = Fields[i].first;
150    Ops[i * 2 + 2] = createConstant(ConstantInt::get(Int64, Fields[i].second));
151  }
152  return MDNode::get(Context, Ops);
153}
154
155/// \brief Return metadata for a TBAA scalar type node with the
156/// given name, an offset and a parent in the TBAA type DAG.
157MDNode *MDBuilder::createTBAAScalarTypeNode(StringRef Name, MDNode *Parent,
158                                            uint64_t Offset) {
159  ConstantInt *Off = ConstantInt::get(Type::getInt64Ty(Context), Offset);
160  return MDNode::get(Context,
161                     {createString(Name), Parent, createConstant(Off)});
162}
163
164/// \brief Return metadata for a TBAA tag node with the given
165/// base type, access type and offset relative to the base type.
166MDNode *MDBuilder::createTBAAStructTagNode(MDNode *BaseType, MDNode *AccessType,
167                                           uint64_t Offset, bool IsConstant) {
168  IntegerType *Int64 = Type::getInt64Ty(Context);
169  ConstantInt *Off = ConstantInt::get(Int64, Offset);
170  if (IsConstant) {
171    return MDNode::get(Context, {BaseType, AccessType, createConstant(Off),
172                                 createConstant(ConstantInt::get(Int64, 1))});
173  }
174  return MDNode::get(Context, {BaseType, AccessType, createConstant(Off)});
175}
176