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"
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(C: ConstantFP::get(Ty: Type::getFloatTy(C&: Context), V: Accuracy));
34 return MDNode::get(Context, MDs: Op);
35}
36
37MDNode *MDBuilder::createBranchWeights(uint32_t TrueWeight,
38 uint32_t FalseWeight, bool IsExpected) {
39 return createBranchWeights(Weights: {TrueWeight, FalseWeight}, IsExpected);
40}
41
42MDNode *MDBuilder::createLikelyBranchWeights() {
43 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
44 return createBranchWeights(TrueWeight: (1U << 20) - 1, FalseWeight: 1);
45}
46
47MDNode *MDBuilder::createUnlikelyBranchWeights() {
48 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
49 return createBranchWeights(TrueWeight: 1, FalseWeight: (1U << 20) - 1);
50}
51
52MDNode *MDBuilder::createBranchWeights(ArrayRef<uint32_t> Weights,
53 bool IsExpected) {
54 assert(Weights.size() >= 1 && "Need at least one branch weights!");
55
56 unsigned int Offset = IsExpected ? 2 : 1;
57 SmallVector<Metadata *, 4> Vals(Weights.size() + Offset);
58 Vals[0] = createString(Str: "branch_weights");
59 if (IsExpected)
60 Vals[1] = createString(Str: "expected");
61
62 Type *Int32Ty = Type::getInt32Ty(C&: Context);
63 for (unsigned i = 0, e = Weights.size(); i != e; ++i)
64 Vals[i + Offset] = createConstant(C: ConstantInt::get(Ty: Int32Ty, V: Weights[i]));
65
66 return MDNode::get(Context, MDs: Vals);
67}
68
69MDNode *MDBuilder::createUnpredictable() {
70 return MDNode::get(Context, MDs: std::nullopt);
71}
72
73MDNode *MDBuilder::createFunctionEntryCount(
74 uint64_t Count, bool Synthetic,
75 const DenseSet<GlobalValue::GUID> *Imports) {
76 Type *Int64Ty = Type::getInt64Ty(C&: Context);
77 SmallVector<Metadata *, 8> Ops;
78 if (Synthetic)
79 Ops.push_back(Elt: createString(Str: "synthetic_function_entry_count"));
80 else
81 Ops.push_back(Elt: createString(Str: "function_entry_count"));
82 Ops.push_back(Elt: createConstant(C: ConstantInt::get(Ty: Int64Ty, V: Count)));
83 if (Imports) {
84 SmallVector<GlobalValue::GUID, 2> OrderID(Imports->begin(), Imports->end());
85 llvm::sort(C&: OrderID);
86 for (auto ID : OrderID)
87 Ops.push_back(Elt: createConstant(C: ConstantInt::get(Ty: Int64Ty, V: ID)));
88 }
89 return MDNode::get(Context, MDs: Ops);
90}
91
92MDNode *MDBuilder::createFunctionSectionPrefix(StringRef Prefix) {
93 return MDNode::get(
94 Context, MDs: {createString(Str: "function_section_prefix"), createString(Str: Prefix)});
95}
96
97MDNode *MDBuilder::createRange(const APInt &Lo, const APInt &Hi) {
98 assert(Lo.getBitWidth() == Hi.getBitWidth() && "Mismatched bitwidths!");
99
100 Type *Ty = IntegerType::get(C&: Context, NumBits: Lo.getBitWidth());
101 return createRange(Lo: ConstantInt::get(Ty, V: Lo), Hi: ConstantInt::get(Ty, V: Hi));
102}
103
104MDNode *MDBuilder::createRange(Constant *Lo, Constant *Hi) {
105 // If the range is everything then it is useless.
106 if (Hi == Lo)
107 return nullptr;
108
109 // Return the range [Lo, Hi).
110 return MDNode::get(Context, MDs: {createConstant(C: Lo), createConstant(C: Hi)});
111}
112
113MDNode *MDBuilder::createCallees(ArrayRef<Function *> Callees) {
114 SmallVector<Metadata *, 4> Ops;
115 for (Function *F : Callees)
116 Ops.push_back(Elt: createConstant(C: F));
117 return MDNode::get(Context, MDs: Ops);
118}
119
120MDNode *MDBuilder::createCallbackEncoding(unsigned CalleeArgNo,
121 ArrayRef<int> Arguments,
122 bool VarArgArePassed) {
123 SmallVector<Metadata *, 4> Ops;
124
125 Type *Int64 = Type::getInt64Ty(C&: Context);
126 Ops.push_back(Elt: createConstant(C: ConstantInt::get(Ty: Int64, V: CalleeArgNo)));
127
128 for (int ArgNo : Arguments)
129 Ops.push_back(Elt: createConstant(C: ConstantInt::get(Ty: Int64, V: ArgNo, IsSigned: true)));
130
131 Type *Int1 = Type::getInt1Ty(C&: Context);
132 Ops.push_back(Elt: createConstant(C: ConstantInt::get(Ty: Int1, V: VarArgArePassed)));
133
134 return MDNode::get(Context, MDs: Ops);
135}
136
137MDNode *MDBuilder::mergeCallbackEncodings(MDNode *ExistingCallbacks,
138 MDNode *NewCB) {
139 if (!ExistingCallbacks)
140 return MDNode::get(Context, MDs: {NewCB});
141
142 auto *NewCBCalleeIdxAsCM = cast<ConstantAsMetadata>(Val: NewCB->getOperand(I: 0));
143 uint64_t NewCBCalleeIdx =
144 cast<ConstantInt>(Val: NewCBCalleeIdxAsCM->getValue())->getZExtValue();
145 (void)NewCBCalleeIdx;
146
147 SmallVector<Metadata *, 4> Ops;
148 unsigned NumExistingOps = ExistingCallbacks->getNumOperands();
149 Ops.resize(N: NumExistingOps + 1);
150
151 for (unsigned u = 0; u < NumExistingOps; u++) {
152 Ops[u] = ExistingCallbacks->getOperand(I: u);
153
154 auto *OldCBCalleeIdxAsCM =
155 cast<ConstantAsMetadata>(Val: cast<MDNode>(Val: Ops[u])->getOperand(I: 0));
156 uint64_t OldCBCalleeIdx =
157 cast<ConstantInt>(Val: OldCBCalleeIdxAsCM->getValue())->getZExtValue();
158 (void)OldCBCalleeIdx;
159 assert(NewCBCalleeIdx != OldCBCalleeIdx &&
160 "Cannot map a callback callee index twice!");
161 }
162
163 Ops[NumExistingOps] = NewCB;
164 return MDNode::get(Context, MDs: Ops);
165}
166
167MDNode *MDBuilder::createRTTIPointerPrologue(Constant *PrologueSig,
168 Constant *RTTI) {
169 SmallVector<Metadata *, 4> Ops;
170 Ops.push_back(Elt: createConstant(C: PrologueSig));
171 Ops.push_back(Elt: createConstant(C: RTTI));
172 return MDNode::get(Context, MDs: Ops);
173}
174
175MDNode *MDBuilder::createPCSections(ArrayRef<PCSection> Sections) {
176 SmallVector<Metadata *, 2> Ops;
177
178 for (const auto &Entry : Sections) {
179 const StringRef &Sec = Entry.first;
180 Ops.push_back(Elt: createString(Str: Sec));
181
182 // If auxiliary data for this section exists, append it.
183 const SmallVector<Constant *> &AuxConsts = Entry.second;
184 if (!AuxConsts.empty()) {
185 SmallVector<Metadata *, 1> AuxMDs;
186 AuxMDs.reserve(N: AuxConsts.size());
187 for (Constant *C : AuxConsts)
188 AuxMDs.push_back(Elt: createConstant(C));
189 Ops.push_back(Elt: MDNode::get(Context, MDs: AuxMDs));
190 }
191 }
192
193 return MDNode::get(Context, MDs: Ops);
194}
195
196MDNode *MDBuilder::createAnonymousAARoot(StringRef Name, MDNode *Extra) {
197 SmallVector<Metadata *, 3> Args(1, nullptr);
198 if (Extra)
199 Args.push_back(Elt: Extra);
200 if (!Name.empty())
201 Args.push_back(Elt: createString(Str: Name));
202 MDNode *Root = MDNode::getDistinct(Context, MDs: Args);
203
204 // At this point we have
205 // !0 = distinct !{null} <- root
206 // Replace the reserved operand with the root node itself.
207 Root->replaceOperandWith(I: 0, New: Root);
208
209 // We now have
210 // !0 = distinct !{!0} <- root
211 return Root;
212}
213
214MDNode *MDBuilder::createTBAARoot(StringRef Name) {
215 return MDNode::get(Context, MDs: createString(Str: Name));
216}
217
218/// Return metadata for a non-root TBAA node with the given name,
219/// parent in the TBAA tree, and value for 'pointsToConstantMemory'.
220MDNode *MDBuilder::createTBAANode(StringRef Name, MDNode *Parent,
221 bool isConstant) {
222 if (isConstant) {
223 Constant *Flags = ConstantInt::get(Ty: Type::getInt64Ty(C&: Context), V: 1);
224 return MDNode::get(Context,
225 MDs: {createString(Str: Name), Parent, createConstant(C: Flags)});
226 }
227 return MDNode::get(Context, MDs: {createString(Str: Name), Parent});
228}
229
230MDNode *MDBuilder::createAliasScopeDomain(StringRef Name) {
231 return MDNode::get(Context, MDs: createString(Str: Name));
232}
233
234MDNode *MDBuilder::createAliasScope(StringRef Name, MDNode *Domain) {
235 return MDNode::get(Context, MDs: {createString(Str: Name), Domain});
236}
237
238/// Return metadata for a tbaa.struct node with the given
239/// struct field descriptions.
240MDNode *MDBuilder::createTBAAStructNode(ArrayRef<TBAAStructField> Fields) {
241 SmallVector<Metadata *, 4> Vals(Fields.size() * 3);
242 Type *Int64 = Type::getInt64Ty(C&: Context);
243 for (unsigned i = 0, e = Fields.size(); i != e; ++i) {
244 Vals[i * 3 + 0] = createConstant(C: ConstantInt::get(Ty: Int64, V: Fields[i].Offset));
245 Vals[i * 3 + 1] = createConstant(C: ConstantInt::get(Ty: Int64, V: Fields[i].Size));
246 Vals[i * 3 + 2] = Fields[i].Type;
247 }
248 return MDNode::get(Context, MDs: Vals);
249}
250
251/// Return metadata for a TBAA struct node in the type DAG
252/// with the given name, a list of pairs (offset, field type in the type DAG).
253MDNode *MDBuilder::createTBAAStructTypeNode(
254 StringRef Name, ArrayRef<std::pair<MDNode *, uint64_t>> Fields) {
255 SmallVector<Metadata *, 4> Ops(Fields.size() * 2 + 1);
256 Type *Int64 = Type::getInt64Ty(C&: Context);
257 Ops[0] = createString(Str: Name);
258 for (unsigned i = 0, e = Fields.size(); i != e; ++i) {
259 Ops[i * 2 + 1] = Fields[i].first;
260 Ops[i * 2 + 2] = createConstant(C: ConstantInt::get(Ty: Int64, V: Fields[i].second));
261 }
262 return MDNode::get(Context, MDs: Ops);
263}
264
265/// Return metadata for a TBAA scalar type node with the
266/// given name, an offset and a parent in the TBAA type DAG.
267MDNode *MDBuilder::createTBAAScalarTypeNode(StringRef Name, MDNode *Parent,
268 uint64_t Offset) {
269 ConstantInt *Off = ConstantInt::get(Ty: Type::getInt64Ty(C&: Context), V: Offset);
270 return MDNode::get(Context,
271 MDs: {createString(Str: Name), Parent, createConstant(C: Off)});
272}
273
274/// Return metadata for a TBAA tag node with the given
275/// base type, access type and offset relative to the base type.
276MDNode *MDBuilder::createTBAAStructTagNode(MDNode *BaseType, MDNode *AccessType,
277 uint64_t Offset, bool IsConstant) {
278 IntegerType *Int64 = Type::getInt64Ty(C&: Context);
279 ConstantInt *Off = ConstantInt::get(Ty: Int64, V: Offset);
280 if (IsConstant) {
281 return MDNode::get(Context, MDs: {BaseType, AccessType, createConstant(C: Off),
282 createConstant(C: ConstantInt::get(Ty: Int64, V: 1))});
283 }
284 return MDNode::get(Context, MDs: {BaseType, AccessType, createConstant(C: Off)});
285}
286
287MDNode *MDBuilder::createTBAATypeNode(MDNode *Parent, uint64_t Size,
288 Metadata *Id,
289 ArrayRef<TBAAStructField> Fields) {
290 SmallVector<Metadata *, 4> Ops(3 + Fields.size() * 3);
291 Type *Int64 = Type::getInt64Ty(C&: Context);
292 Ops[0] = Parent;
293 Ops[1] = createConstant(C: ConstantInt::get(Ty: Int64, V: Size));
294 Ops[2] = Id;
295 for (unsigned I = 0, E = Fields.size(); I != E; ++I) {
296 Ops[I * 3 + 3] = Fields[I].Type;
297 Ops[I * 3 + 4] = createConstant(C: ConstantInt::get(Ty: Int64, V: Fields[I].Offset));
298 Ops[I * 3 + 5] = createConstant(C: ConstantInt::get(Ty: Int64, V: Fields[I].Size));
299 }
300 return MDNode::get(Context, MDs: Ops);
301}
302
303MDNode *MDBuilder::createTBAAAccessTag(MDNode *BaseType, MDNode *AccessType,
304 uint64_t Offset, uint64_t Size,
305 bool IsImmutable) {
306 IntegerType *Int64 = Type::getInt64Ty(C&: Context);
307 auto *OffsetNode = createConstant(C: ConstantInt::get(Ty: Int64, V: Offset));
308 auto *SizeNode = createConstant(C: ConstantInt::get(Ty: Int64, V: Size));
309 if (IsImmutable) {
310 auto *ImmutabilityFlagNode = createConstant(C: ConstantInt::get(Ty: Int64, V: 1));
311 return MDNode::get(Context, MDs: {BaseType, AccessType, OffsetNode, SizeNode,
312 ImmutabilityFlagNode});
313 }
314 return MDNode::get(Context, MDs: {BaseType, AccessType, OffsetNode, SizeNode});
315}
316
317MDNode *MDBuilder::createMutableTBAAAccessTag(MDNode *Tag) {
318 MDNode *BaseType = cast<MDNode>(Val: Tag->getOperand(I: 0));
319 MDNode *AccessType = cast<MDNode>(Val: Tag->getOperand(I: 1));
320 Metadata *OffsetNode = Tag->getOperand(I: 2);
321 uint64_t Offset = mdconst::extract<ConstantInt>(MD&: OffsetNode)->getZExtValue();
322
323 bool NewFormat = isa<MDNode>(Val: AccessType->getOperand(I: 0));
324
325 // See if the tag is already mutable.
326 unsigned ImmutabilityFlagOp = NewFormat ? 4 : 3;
327 if (Tag->getNumOperands() <= ImmutabilityFlagOp)
328 return Tag;
329
330 // If Tag is already mutable then return it.
331 Metadata *ImmutabilityFlagNode = Tag->getOperand(I: ImmutabilityFlagOp);
332 if (!mdconst::extract<ConstantInt>(MD&: ImmutabilityFlagNode)->getValue())
333 return Tag;
334
335 // Otherwise, create another node.
336 if (!NewFormat)
337 return createTBAAStructTagNode(BaseType, AccessType, Offset);
338
339 Metadata *SizeNode = Tag->getOperand(I: 3);
340 uint64_t Size = mdconst::extract<ConstantInt>(MD&: SizeNode)->getZExtValue();
341 return createTBAAAccessTag(BaseType, AccessType, Offset, Size);
342}
343
344MDNode *MDBuilder::createIrrLoopHeaderWeight(uint64_t Weight) {
345 Metadata *Vals[] = {
346 createString(Str: "loop_header_weight"),
347 createConstant(C: ConstantInt::get(Ty: Type::getInt64Ty(C&: Context), V: Weight)),
348 };
349 return MDNode::get(Context, MDs: Vals);
350}
351
352MDNode *MDBuilder::createPseudoProbeDesc(uint64_t GUID, uint64_t Hash,
353 StringRef FName) {
354 auto *Int64Ty = Type::getInt64Ty(C&: Context);
355 SmallVector<Metadata *, 3> Ops(3);
356 Ops[0] = createConstant(C: ConstantInt::get(Ty: Int64Ty, V: GUID));
357 Ops[1] = createConstant(C: ConstantInt::get(Ty: Int64Ty, V: Hash));
358 Ops[2] = createString(Str: FName);
359 return MDNode::get(Context, MDs: Ops);
360}
361
362MDNode *
363MDBuilder::createLLVMStats(ArrayRef<std::pair<StringRef, uint64_t>> LLVMStats) {
364 auto *Int64Ty = Type::getInt64Ty(C&: Context);
365 SmallVector<Metadata *, 4> Ops(LLVMStats.size() * 2);
366 for (size_t I = 0; I < LLVMStats.size(); I++) {
367 Ops[I * 2] = createString(Str: LLVMStats[I].first);
368 Ops[I * 2 + 1] =
369 createConstant(C: ConstantInt::get(Ty: Int64Ty, V: LLVMStats[I].second));
370 }
371 return MDNode::get(Context, MDs: Ops);
372}
373