1 //=-- InstrProf.cpp - Instrumented profiling format support -----------------=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for clang's instrumentation based PGO and
13 //===----------------------------------------------------------------------===//
15 #include "llvm/IR/Constants.h"
16 #include "llvm/IR/Function.h"
17 #include "llvm/IR/Module.h"
18 #include "llvm/IR/GlobalVariable.h"
19 #include "llvm/ProfileData/InstrProf.h"
20 #include "llvm/Support/ErrorHandling.h"
21 #include "llvm/Support/ManagedStatic.h"
26 class InstrProfErrorCategoryType : public std::error_category {
27 const char *name() const LLVM_NOEXCEPT override { return "llvm.instrprof"; }
28 std::string message(int IE) const override {
29 instrprof_error E = static_cast<instrprof_error>(IE);
31 case instrprof_error::success:
33 case instrprof_error::eof:
35 case instrprof_error::unrecognized_format:
36 return "Unrecognized instrumentation profile encoding format";
37 case instrprof_error::bad_magic:
38 return "Invalid instrumentation profile data (bad magic)";
39 case instrprof_error::bad_header:
40 return "Invalid instrumentation profile data (file header is corrupt)";
41 case instrprof_error::unsupported_version:
42 return "Unsupported instrumentation profile format version";
43 case instrprof_error::unsupported_hash_type:
44 return "Unsupported instrumentation profile hash type";
45 case instrprof_error::too_large:
46 return "Too much profile data";
47 case instrprof_error::truncated:
48 return "Truncated profile data";
49 case instrprof_error::malformed:
50 return "Malformed instrumentation profile data";
51 case instrprof_error::unknown_function:
52 return "No profile data available for function";
53 case instrprof_error::hash_mismatch:
54 return "Function control flow change detected (hash mismatch)";
55 case instrprof_error::count_mismatch:
56 return "Function basic block count change detected (counter mismatch)";
57 case instrprof_error::counter_overflow:
58 return "Counter overflow";
59 case instrprof_error::value_site_count_mismatch:
60 return "Function value site count change detected (counter mismatch)";
62 llvm_unreachable("A value of instrprof_error has no message.");
67 static ManagedStatic<InstrProfErrorCategoryType> ErrorCategory;
69 const std::error_category &llvm::instrprof_category() {
70 return *ErrorCategory;
75 std::string getPGOFuncName(StringRef RawFuncName,
76 GlobalValue::LinkageTypes Linkage,
79 // Function names may be prefixed with a binary '1' to indicate
80 // that the backend should not modify the symbols due to any platform
81 // naming convention. Do not include that '1' in the PGO profile name.
82 if (RawFuncName[0] == '\1')
83 RawFuncName = RawFuncName.substr(1);
85 std::string FuncName = RawFuncName;
86 if (llvm::GlobalValue::isLocalLinkage(Linkage)) {
87 // For local symbols, prepend the main file name to distinguish them.
88 // Do not include the full path in the file name since there's no guarantee
89 // that it will stay the same, e.g., if the files are checked out from
90 // version control in different locations.
92 FuncName = FuncName.insert(0, "<unknown>:");
94 FuncName = FuncName.insert(0, FileName.str() + ":");
99 std::string getPGOFuncName(const Function &F) {
100 return getPGOFuncName(F.getName(), F.getLinkage(), F.getParent()->getName());
103 GlobalVariable *createPGOFuncNameVar(Module &M,
104 GlobalValue::LinkageTypes Linkage,
105 StringRef FuncName) {
107 // We generally want to match the function's linkage, but available_externally
108 // and extern_weak both have the wrong semantics, and anything that doesn't
109 // need to link across compilation units doesn't need to be visible at all.
110 if (Linkage == GlobalValue::ExternalWeakLinkage)
111 Linkage = GlobalValue::LinkOnceAnyLinkage;
112 else if (Linkage == GlobalValue::AvailableExternallyLinkage)
113 Linkage = GlobalValue::LinkOnceODRLinkage;
114 else if (Linkage == GlobalValue::InternalLinkage ||
115 Linkage == GlobalValue::ExternalLinkage)
116 Linkage = GlobalValue::PrivateLinkage;
118 auto *Value = ConstantDataArray::getString(M.getContext(), FuncName, false);
120 new GlobalVariable(M, Value->getType(), true, Linkage, Value,
121 Twine(getInstrProfNameVarPrefix()) + FuncName);
123 // Hide the symbol so that we correctly get a copy for each executable.
124 if (!GlobalValue::isLocalLinkage(FuncNameVar->getLinkage()))
125 FuncNameVar->setVisibility(GlobalValue::HiddenVisibility);
130 GlobalVariable *createPGOFuncNameVar(Function &F, StringRef FuncName) {
131 return createPGOFuncNameVar(*F.getParent(), F.getLinkage(), FuncName);
134 /// Return the total size in bytes of the on-disk value profile data
135 /// given the data stored in Record.
136 uint32_t getValueProfDataSize(ValueProfRecordClosure *Closure) {
138 uint32_t TotalSize = sizeof(ValueProfData);
139 const void *Record = Closure->Record;
140 uint32_t NumValueKinds = Closure->GetNumValueKinds(Record);
141 if (NumValueKinds == 0)
144 for (Kind = IPVK_First; Kind <= IPVK_Last; Kind++) {
145 uint32_t NumValueSites = Closure->GetNumValueSites(Record, Kind);
148 TotalSize += getValueProfRecordSize(NumValueSites,
149 Closure->GetNumValueData(Record, Kind));
154 // Extract data from \c Closure and serialize into \c This instance.
155 void serializeValueProfRecordFrom(ValueProfRecord *This,
156 ValueProfRecordClosure *Closure,
157 uint32_t ValueKind, uint32_t NumValueSites) {
159 const void *Record = Closure->Record;
160 This->Kind = ValueKind;
161 This->NumValueSites = NumValueSites;
162 InstrProfValueData *DstVD = getValueProfRecordValueData(This);
164 for (S = 0; S < NumValueSites; S++) {
165 uint32_t ND = Closure->GetNumValueDataForSite(Record, ValueKind, S);
166 This->SiteCountArray[S] = ND;
167 Closure->GetValueForSite(Record, DstVD, ValueKind, S,
168 Closure->RemapValueData);
173 ValueProfData *serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
174 ValueProfData *DstData) {
175 uint32_t TotalSize = getValueProfDataSize(Closure);
178 DstData ? DstData : Closure->AllocValueProfData(TotalSize);
180 VPD->TotalSize = TotalSize;
181 VPD->NumValueKinds = Closure->GetNumValueKinds(Closure->Record);
182 ValueProfRecord *VR = getFirstValueProfRecord(VPD);
183 for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; Kind++) {
184 uint32_t NumValueSites = Closure->GetNumValueSites(Closure->Record, Kind);
187 serializeValueProfRecordFrom(VR, Closure, Kind, NumValueSites);
188 VR = getValueProfRecordNext(VR);
193 /*! \brief ValueProfRecordClosure Interface implementation for InstrProfRecord
194 * class. These C wrappers are used as adaptors so that C++ code can be
195 * invoked as callbacks.
197 uint32_t getNumValueKindsInstrProf(const void *Record) {
198 return reinterpret_cast<const InstrProfRecord *>(Record)->getNumValueKinds();
201 uint32_t getNumValueSitesInstrProf(const void *Record, uint32_t VKind) {
202 return reinterpret_cast<const InstrProfRecord *>(Record)
203 ->getNumValueSites(VKind);
206 uint32_t getNumValueDataInstrProf(const void *Record, uint32_t VKind) {
207 return reinterpret_cast<const InstrProfRecord *>(Record)
208 ->getNumValueData(VKind);
211 uint32_t getNumValueDataForSiteInstrProf(const void *R, uint32_t VK,
213 return reinterpret_cast<const InstrProfRecord *>(R)
214 ->getNumValueDataForSite(VK, S);
217 void getValueForSiteInstrProf(const void *R, InstrProfValueData *Dst,
218 uint32_t K, uint32_t S,
219 uint64_t (*Mapper)(uint32_t, uint64_t)) {
220 return reinterpret_cast<const InstrProfRecord *>(R)
221 ->getValueForSite(Dst, K, S, Mapper);
224 uint64_t stringToHash(uint32_t ValueKind, uint64_t Value) {
226 case IPVK_IndirectCallTarget:
227 return IndexedInstrProf::ComputeHash(IndexedInstrProf::HashType,
228 (const char *)Value);
231 llvm_unreachable("value kind not handled !");
236 ValueProfData *allocValueProfDataInstrProf(size_t TotalSizeInBytes) {
237 return (ValueProfData *)(new (::operator new(TotalSizeInBytes))
241 static ValueProfRecordClosure InstrProfRecordClosure = {
243 getNumValueKindsInstrProf,
244 getNumValueSitesInstrProf,
245 getNumValueDataInstrProf,
246 getNumValueDataForSiteInstrProf,
248 getValueForSiteInstrProf,
249 allocValueProfDataInstrProf
252 // Wrapper implementation using the closure mechanism.
253 uint32_t ValueProfData::getSize(const InstrProfRecord &Record) {
254 InstrProfRecordClosure.Record = &Record;
255 return getValueProfDataSize(&InstrProfRecordClosure);
258 // Wrapper implementation using the closure mechanism.
259 std::unique_ptr<ValueProfData>
260 ValueProfData::serializeFrom(const InstrProfRecord &Record) {
261 InstrProfRecordClosure.Record = &Record;
263 std::unique_ptr<ValueProfData> VPD(
264 serializeValueProfDataFrom(&InstrProfRecordClosure, 0));
268 /* The value profiler runtime library stores the value profile data
269 * for a given function in NumValueSites and Nodes. This is the
270 * method to initialize the RuntimeRecord with the runtime data to
271 * pre-compute the information needed to efficiently implement
272 * ValueProfRecordClosure's callback interfaces.
274 void initializeValueProfRuntimeRecord(ValueProfRuntimeRecord *RuntimeRecord,
275 uint16_t *NumValueSites,
276 ValueProfNode **Nodes) {
277 unsigned I, J, S = 0, NumValueKinds = 0;
278 RuntimeRecord->NumValueSites = NumValueSites;
279 RuntimeRecord->Nodes = Nodes;
280 for (I = 0; I <= IPVK_Last; I++) {
281 uint16_t N = NumValueSites[I];
283 RuntimeRecord->SiteCountArray[I] = 0;
287 RuntimeRecord->SiteCountArray[I] = (uint8_t *)calloc(N, 1);
288 RuntimeRecord->NodesKind[I] = &RuntimeRecord->Nodes[S];
289 for (J = 0; J < N; J++) {
291 ValueProfNode *Site = RuntimeRecord->Nodes[S + J];
298 RuntimeRecord->SiteCountArray[I][J] = C;
302 RuntimeRecord->NumValueKinds = NumValueKinds;
305 void finalizeValueProfRuntimeRecord(ValueProfRuntimeRecord *RuntimeRecord) {
307 for (I = 0; I <= IPVK_Last; I++) {
308 if (RuntimeRecord->SiteCountArray[I])
309 free(RuntimeRecord->SiteCountArray[I]);
313 /* ValueProfRecordClosure Interface implementation for
314 * ValueProfDataRuntimeRecord. */
315 uint32_t getNumValueKindsRT(const void *R) {
316 return ((const ValueProfRuntimeRecord *)R)->NumValueKinds;
319 uint32_t getNumValueSitesRT(const void *R, uint32_t VK) {
320 return ((const ValueProfRuntimeRecord *)R)->NumValueSites[VK];
323 uint32_t getNumValueDataForSiteRT(const void *R, uint32_t VK, uint32_t S) {
324 const ValueProfRuntimeRecord *Record = (const ValueProfRuntimeRecord *)R;
325 return Record->SiteCountArray[VK][S];
328 uint32_t getNumValueDataRT(const void *R, uint32_t VK) {
330 const ValueProfRuntimeRecord *Record = (const ValueProfRuntimeRecord *)R;
331 if (Record->SiteCountArray[VK] == 0)
333 for (I = 0; I < Record->NumValueSites[VK]; I++)
334 S += Record->SiteCountArray[VK][I];
338 void getValueForSiteRT(const void *R, InstrProfValueData *Dst, uint32_t VK,
339 uint32_t S, uint64_t (*Mapper)(uint32_t, uint64_t)) {
341 const ValueProfRuntimeRecord *Record = (const ValueProfRuntimeRecord *)R;
342 N = getNumValueDataForSiteRT(R, VK, S);
343 ValueProfNode *VNode = Record->NodesKind[VK][S];
344 for (I = 0; I < N; I++) {
345 Dst[I] = VNode->VData;
350 ValueProfData *allocValueProfDataRT(size_t TotalSizeInBytes) {
351 return (ValueProfData *)calloc(TotalSizeInBytes, 1);
354 static ValueProfRecordClosure RTRecordClosure = {0,
358 getNumValueDataForSiteRT,
361 allocValueProfDataRT};
363 /* Return the size of ValueProfData structure to store data
364 * recorded in the runtime record.
366 uint32_t getValueProfDataSizeRT(const ValueProfRuntimeRecord *Record) {
367 RTRecordClosure.Record = Record;
368 return getValueProfDataSize(&RTRecordClosure);
371 /* Return a ValueProfData instance that stores the data collected
372 * from runtime. If \c DstData is provided by the caller, the value
373 * profile data will be store in *DstData and DstData is returned,
374 * otherwise the method will allocate space for the value data and
375 * return pointer to the newly allocated space.
378 serializeValueProfDataFromRT(const ValueProfRuntimeRecord *Record,
379 ValueProfData *DstData) {
380 RTRecordClosure.Record = Record;
381 return serializeValueProfDataFrom(&RTRecordClosure, DstData);
384 void ValueProfRecord::deserializeTo(InstrProfRecord &Record,
385 InstrProfRecord::ValueMapType *VMap) {
386 Record.reserveSites(Kind, NumValueSites);
388 InstrProfValueData *ValueData = getValueProfRecordValueData(this);
389 for (uint64_t VSite = 0; VSite < NumValueSites; ++VSite) {
390 uint8_t ValueDataCount = this->SiteCountArray[VSite];
391 Record.addValueData(Kind, VSite, ValueData, ValueDataCount, VMap);
392 ValueData += ValueDataCount;
396 // For writing/serializing, Old is the host endianness, and New is
397 // byte order intended on disk. For Reading/deserialization, Old
398 // is the on-disk source endianness, and New is the host endianness.
399 void ValueProfRecord::swapBytes(support::endianness Old,
400 support::endianness New) {
401 using namespace support;
405 if (getHostEndianness() != Old) {
406 sys::swapByteOrder<uint32_t>(NumValueSites);
407 sys::swapByteOrder<uint32_t>(Kind);
409 uint32_t ND = getValueProfRecordNumValueData(this);
410 InstrProfValueData *VD = getValueProfRecordValueData(this);
412 // No need to swap byte array: SiteCountArrray.
413 for (uint32_t I = 0; I < ND; I++) {
414 sys::swapByteOrder<uint64_t>(VD[I].Value);
415 sys::swapByteOrder<uint64_t>(VD[I].Count);
417 if (getHostEndianness() == Old) {
418 sys::swapByteOrder<uint32_t>(NumValueSites);
419 sys::swapByteOrder<uint32_t>(Kind);
423 void ValueProfData::deserializeTo(InstrProfRecord &Record,
424 InstrProfRecord::ValueMapType *VMap) {
425 if (NumValueKinds == 0)
428 ValueProfRecord *VR = getFirstValueProfRecord(this);
429 for (uint32_t K = 0; K < NumValueKinds; K++) {
430 VR->deserializeTo(Record, VMap);
431 VR = getValueProfRecordNext(VR);
436 static T swapToHostOrder(const unsigned char *&D, support::endianness Orig) {
437 using namespace support;
439 return endian::readNext<T, little, unaligned>(D);
441 return endian::readNext<T, big, unaligned>(D);
444 static std::unique_ptr<ValueProfData> allocValueProfData(uint32_t TotalSize) {
445 return std::unique_ptr<ValueProfData>(new (::operator new(TotalSize))
449 instrprof_error ValueProfData::checkIntegrity() {
450 if (NumValueKinds > IPVK_Last + 1)
451 return instrprof_error::malformed;
452 // Total size needs to be mulltiple of quadword size.
453 if (TotalSize % sizeof(uint64_t))
454 return instrprof_error::malformed;
456 ValueProfRecord *VR = getFirstValueProfRecord(this);
457 for (uint32_t K = 0; K < this->NumValueKinds; K++) {
458 if (VR->Kind > IPVK_Last)
459 return instrprof_error::malformed;
460 VR = getValueProfRecordNext(VR);
461 if ((char *)VR - (char *)this > (ptrdiff_t)TotalSize)
462 return instrprof_error::malformed;
464 return instrprof_error::success;
467 ErrorOr<std::unique_ptr<ValueProfData>>
468 ValueProfData::getValueProfData(const unsigned char *D,
469 const unsigned char *const BufferEnd,
470 support::endianness Endianness) {
471 using namespace support;
472 if (D + sizeof(ValueProfData) > BufferEnd)
473 return instrprof_error::truncated;
475 const unsigned char *Header = D;
476 uint32_t TotalSize = swapToHostOrder<uint32_t>(Header, Endianness);
477 if (D + TotalSize > BufferEnd)
478 return instrprof_error::too_large;
480 std::unique_ptr<ValueProfData> VPD = allocValueProfData(TotalSize);
481 memcpy(VPD.get(), D, TotalSize);
483 VPD->swapBytesToHost(Endianness);
485 instrprof_error EC = VPD->checkIntegrity();
486 if (EC != instrprof_error::success)
489 return std::move(VPD);
492 void ValueProfData::swapBytesToHost(support::endianness Endianness) {
493 using namespace support;
494 if (Endianness == getHostEndianness())
497 sys::swapByteOrder<uint32_t>(TotalSize);
498 sys::swapByteOrder<uint32_t>(NumValueKinds);
500 ValueProfRecord *VR = getFirstValueProfRecord(this);
501 for (uint32_t K = 0; K < NumValueKinds; K++) {
502 VR->swapBytes(Endianness, getHostEndianness());
503 VR = getValueProfRecordNext(VR);
507 void ValueProfData::swapBytesFromHost(support::endianness Endianness) {
508 using namespace support;
509 if (Endianness == getHostEndianness())
512 ValueProfRecord *VR = getFirstValueProfRecord(this);
513 for (uint32_t K = 0; K < NumValueKinds; K++) {
514 ValueProfRecord *NVR = getValueProfRecordNext(VR);
515 VR->swapBytes(getHostEndianness(), Endianness);
518 sys::swapByteOrder<uint32_t>(TotalSize);
519 sys::swapByteOrder<uint32_t>(NumValueKinds);