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,
78 uint64_t Version LLVM_ATTRIBUTE_UNUSED) {
80 // Function names may be prefixed with a binary '1' to indicate
81 // that the backend should not modify the symbols due to any platform
82 // naming convention. Do not include that '1' in the PGO profile name.
83 if (RawFuncName[0] == '\1')
84 RawFuncName = RawFuncName.substr(1);
86 std::string FuncName = RawFuncName;
87 if (llvm::GlobalValue::isLocalLinkage(Linkage)) {
88 // For local symbols, prepend the main file name to distinguish them.
89 // Do not include the full path in the file name since there's no guarantee
90 // that it will stay the same, e.g., if the files are checked out from
91 // version control in different locations.
93 FuncName = FuncName.insert(0, "<unknown>:");
95 FuncName = FuncName.insert(0, FileName.str() + ":");
100 std::string getPGOFuncName(const Function &F, uint64_t Version) {
101 return getPGOFuncName(F.getName(), F.getLinkage(), F.getParent()->getName(),
105 GlobalVariable *createPGOFuncNameVar(Module &M,
106 GlobalValue::LinkageTypes Linkage,
107 StringRef FuncName) {
109 // We generally want to match the function's linkage, but available_externally
110 // and extern_weak both have the wrong semantics, and anything that doesn't
111 // need to link across compilation units doesn't need to be visible at all.
112 if (Linkage == GlobalValue::ExternalWeakLinkage)
113 Linkage = GlobalValue::LinkOnceAnyLinkage;
114 else if (Linkage == GlobalValue::AvailableExternallyLinkage)
115 Linkage = GlobalValue::LinkOnceODRLinkage;
116 else if (Linkage == GlobalValue::InternalLinkage ||
117 Linkage == GlobalValue::ExternalLinkage)
118 Linkage = GlobalValue::PrivateLinkage;
120 auto *Value = ConstantDataArray::getString(M.getContext(), FuncName, false);
122 new GlobalVariable(M, Value->getType(), true, Linkage, Value,
123 Twine(getInstrProfNameVarPrefix()) + FuncName);
125 // Hide the symbol so that we correctly get a copy for each executable.
126 if (!GlobalValue::isLocalLinkage(FuncNameVar->getLinkage()))
127 FuncNameVar->setVisibility(GlobalValue::HiddenVisibility);
132 GlobalVariable *createPGOFuncNameVar(Function &F, StringRef FuncName) {
133 return createPGOFuncNameVar(*F.getParent(), F.getLinkage(), FuncName);
136 #define INSTR_PROF_COMMON_API_IMPL
137 #include "llvm/ProfileData/InstrProfData.inc"
141 * \brief ValueProfRecordClosure Interface implementation for InstrProfRecord
142 * class. These C wrappers are used as adaptors so that C++ code can be
143 * invoked as callbacks.
145 uint32_t getNumValueKindsInstrProf(const void *Record) {
146 return reinterpret_cast<const InstrProfRecord *>(Record)->getNumValueKinds();
149 uint32_t getNumValueSitesInstrProf(const void *Record, uint32_t VKind) {
150 return reinterpret_cast<const InstrProfRecord *>(Record)
151 ->getNumValueSites(VKind);
154 uint32_t getNumValueDataInstrProf(const void *Record, uint32_t VKind) {
155 return reinterpret_cast<const InstrProfRecord *>(Record)
156 ->getNumValueData(VKind);
159 uint32_t getNumValueDataForSiteInstrProf(const void *R, uint32_t VK,
161 return reinterpret_cast<const InstrProfRecord *>(R)
162 ->getNumValueDataForSite(VK, S);
165 void getValueForSiteInstrProf(const void *R, InstrProfValueData *Dst,
166 uint32_t K, uint32_t S,
167 uint64_t (*Mapper)(uint32_t, uint64_t)) {
168 return reinterpret_cast<const InstrProfRecord *>(R)
169 ->getValueForSite(Dst, K, S, Mapper);
172 uint64_t stringToHash(uint32_t ValueKind, uint64_t Value) {
174 case IPVK_IndirectCallTarget:
175 return IndexedInstrProf::ComputeHash(IndexedInstrProf::HashType,
176 (const char *)Value);
179 llvm_unreachable("value kind not handled !");
184 ValueProfData *allocValueProfDataInstrProf(size_t TotalSizeInBytes) {
185 return (ValueProfData *)(new (::operator new(TotalSizeInBytes))
189 static ValueProfRecordClosure InstrProfRecordClosure = {
191 getNumValueKindsInstrProf,
192 getNumValueSitesInstrProf,
193 getNumValueDataInstrProf,
194 getNumValueDataForSiteInstrProf,
196 getValueForSiteInstrProf,
197 allocValueProfDataInstrProf
200 // Wrapper implementation using the closure mechanism.
201 uint32_t ValueProfData::getSize(const InstrProfRecord &Record) {
202 InstrProfRecordClosure.Record = &Record;
203 return getValueProfDataSize(&InstrProfRecordClosure);
206 // Wrapper implementation using the closure mechanism.
207 std::unique_ptr<ValueProfData>
208 ValueProfData::serializeFrom(const InstrProfRecord &Record) {
209 InstrProfRecordClosure.Record = &Record;
211 std::unique_ptr<ValueProfData> VPD(
212 serializeValueProfDataFrom(&InstrProfRecordClosure, nullptr));
216 void ValueProfRecord::deserializeTo(InstrProfRecord &Record,
217 InstrProfRecord::ValueMapType *VMap) {
218 Record.reserveSites(Kind, NumValueSites);
220 InstrProfValueData *ValueData = getValueProfRecordValueData(this);
221 for (uint64_t VSite = 0; VSite < NumValueSites; ++VSite) {
222 uint8_t ValueDataCount = this->SiteCountArray[VSite];
223 Record.addValueData(Kind, VSite, ValueData, ValueDataCount, VMap);
224 ValueData += ValueDataCount;
228 // For writing/serializing, Old is the host endianness, and New is
229 // byte order intended on disk. For Reading/deserialization, Old
230 // is the on-disk source endianness, and New is the host endianness.
231 void ValueProfRecord::swapBytes(support::endianness Old,
232 support::endianness New) {
233 using namespace support;
237 if (getHostEndianness() != Old) {
238 sys::swapByteOrder<uint32_t>(NumValueSites);
239 sys::swapByteOrder<uint32_t>(Kind);
241 uint32_t ND = getValueProfRecordNumValueData(this);
242 InstrProfValueData *VD = getValueProfRecordValueData(this);
244 // No need to swap byte array: SiteCountArrray.
245 for (uint32_t I = 0; I < ND; I++) {
246 sys::swapByteOrder<uint64_t>(VD[I].Value);
247 sys::swapByteOrder<uint64_t>(VD[I].Count);
249 if (getHostEndianness() == Old) {
250 sys::swapByteOrder<uint32_t>(NumValueSites);
251 sys::swapByteOrder<uint32_t>(Kind);
255 void ValueProfData::deserializeTo(InstrProfRecord &Record,
256 InstrProfRecord::ValueMapType *VMap) {
257 if (NumValueKinds == 0)
260 ValueProfRecord *VR = getFirstValueProfRecord(this);
261 for (uint32_t K = 0; K < NumValueKinds; K++) {
262 VR->deserializeTo(Record, VMap);
263 VR = getValueProfRecordNext(VR);
268 static T swapToHostOrder(const unsigned char *&D, support::endianness Orig) {
269 using namespace support;
271 return endian::readNext<T, little, unaligned>(D);
273 return endian::readNext<T, big, unaligned>(D);
276 static std::unique_ptr<ValueProfData> allocValueProfData(uint32_t TotalSize) {
277 return std::unique_ptr<ValueProfData>(new (::operator new(TotalSize))
281 instrprof_error ValueProfData::checkIntegrity() {
282 if (NumValueKinds > IPVK_Last + 1)
283 return instrprof_error::malformed;
284 // Total size needs to be mulltiple of quadword size.
285 if (TotalSize % sizeof(uint64_t))
286 return instrprof_error::malformed;
288 ValueProfRecord *VR = getFirstValueProfRecord(this);
289 for (uint32_t K = 0; K < this->NumValueKinds; K++) {
290 if (VR->Kind > IPVK_Last)
291 return instrprof_error::malformed;
292 VR = getValueProfRecordNext(VR);
293 if ((char *)VR - (char *)this > (ptrdiff_t)TotalSize)
294 return instrprof_error::malformed;
296 return instrprof_error::success;
299 ErrorOr<std::unique_ptr<ValueProfData>>
300 ValueProfData::getValueProfData(const unsigned char *D,
301 const unsigned char *const BufferEnd,
302 support::endianness Endianness) {
303 using namespace support;
304 if (D + sizeof(ValueProfData) > BufferEnd)
305 return instrprof_error::truncated;
307 const unsigned char *Header = D;
308 uint32_t TotalSize = swapToHostOrder<uint32_t>(Header, Endianness);
309 if (D + TotalSize > BufferEnd)
310 return instrprof_error::too_large;
312 std::unique_ptr<ValueProfData> VPD = allocValueProfData(TotalSize);
313 memcpy(VPD.get(), D, TotalSize);
315 VPD->swapBytesToHost(Endianness);
317 instrprof_error EC = VPD->checkIntegrity();
318 if (EC != instrprof_error::success)
321 return std::move(VPD);
324 void ValueProfData::swapBytesToHost(support::endianness Endianness) {
325 using namespace support;
326 if (Endianness == getHostEndianness())
329 sys::swapByteOrder<uint32_t>(TotalSize);
330 sys::swapByteOrder<uint32_t>(NumValueKinds);
332 ValueProfRecord *VR = getFirstValueProfRecord(this);
333 for (uint32_t K = 0; K < NumValueKinds; K++) {
334 VR->swapBytes(Endianness, getHostEndianness());
335 VR = getValueProfRecordNext(VR);
339 void ValueProfData::swapBytesFromHost(support::endianness Endianness) {
340 using namespace support;
341 if (Endianness == getHostEndianness())
344 ValueProfRecord *VR = getFirstValueProfRecord(this);
345 for (uint32_t K = 0; K < NumValueKinds; K++) {
346 ValueProfRecord *NVR = getValueProfRecordNext(VR);
347 VR->swapBytes(getHostEndianness(), Endianness);
350 sys::swapByteOrder<uint32_t>(TotalSize);
351 sys::swapByteOrder<uint32_t>(NumValueKinds);