1 //=-- SampleProf.h - Sampling 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 common definitions used in the reading and writing of
11 // sample profile data.
13 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_PROFILEDATA_SAMPLEPROF_H_
15 #define LLVM_PROFILEDATA_SAMPLEPROF_H_
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/ADT/StringMap.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/ErrorOr.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include <system_error>
27 const std::error_category &sampleprof_category();
29 enum class sampleprof_error {
37 unsupported_writing_format,
42 inline std::error_code make_error_code(sampleprof_error E) {
43 return std::error_code(static_cast<int>(E), sampleprof_category());
46 } // end namespace llvm
50 struct is_error_code_enum<llvm::sampleprof_error> : std::true_type {};
55 namespace sampleprof {
57 static inline uint64_t SPMagic() {
58 return uint64_t('S') << (64 - 8) | uint64_t('P') << (64 - 16) |
59 uint64_t('R') << (64 - 24) | uint64_t('O') << (64 - 32) |
60 uint64_t('F') << (64 - 40) | uint64_t('4') << (64 - 48) |
61 uint64_t('2') << (64 - 56) | uint64_t(0xff);
64 static inline uint64_t SPVersion() { return 102; }
66 /// Represents the relative location of an instruction.
68 /// Instruction locations are specified by the line offset from the
69 /// beginning of the function (marked by the line where the function
70 /// header is) and the discriminator value within that line.
72 /// The discriminator value is useful to distinguish instructions
73 /// that are on the same line but belong to different basic blocks
74 /// (e.g., the two post-increment instructions in "if (p) x++; else y++;").
76 LineLocation(uint32_t L, uint32_t D) : LineOffset(L), Discriminator(D) {}
78 uint32_t Discriminator;
81 /// Represents the relative location of a callsite.
83 /// Callsite locations are specified by the line offset from the
84 /// beginning of the function (marked by the line where the function
85 /// head is), the discriminator value within that line, and the callee
87 struct CallsiteLocation : public LineLocation {
88 CallsiteLocation(uint32_t L, uint32_t D, StringRef N)
89 : LineLocation(L, D), CalleeName(N) {}
93 } // End namespace sampleprof
95 template <> struct DenseMapInfo<sampleprof::LineLocation> {
96 typedef DenseMapInfo<uint32_t> OffsetInfo;
97 typedef DenseMapInfo<uint32_t> DiscriminatorInfo;
98 static inline sampleprof::LineLocation getEmptyKey() {
99 return sampleprof::LineLocation(OffsetInfo::getEmptyKey(),
100 DiscriminatorInfo::getEmptyKey());
102 static inline sampleprof::LineLocation getTombstoneKey() {
103 return sampleprof::LineLocation(OffsetInfo::getTombstoneKey(),
104 DiscriminatorInfo::getTombstoneKey());
106 static inline unsigned getHashValue(sampleprof::LineLocation Val) {
107 return DenseMapInfo<std::pair<uint32_t, uint32_t>>::getHashValue(
108 std::pair<uint32_t, uint32_t>(Val.LineOffset, Val.Discriminator));
110 static inline bool isEqual(sampleprof::LineLocation LHS,
111 sampleprof::LineLocation RHS) {
112 return LHS.LineOffset == RHS.LineOffset &&
113 LHS.Discriminator == RHS.Discriminator;
117 template <> struct DenseMapInfo<sampleprof::CallsiteLocation> {
118 typedef DenseMapInfo<uint32_t> OffsetInfo;
119 typedef DenseMapInfo<uint32_t> DiscriminatorInfo;
120 typedef DenseMapInfo<StringRef> CalleeNameInfo;
121 static inline sampleprof::CallsiteLocation getEmptyKey() {
122 return sampleprof::CallsiteLocation(OffsetInfo::getEmptyKey(),
123 DiscriminatorInfo::getEmptyKey(), "");
125 static inline sampleprof::CallsiteLocation getTombstoneKey() {
126 return sampleprof::CallsiteLocation(OffsetInfo::getTombstoneKey(),
127 DiscriminatorInfo::getTombstoneKey(),
130 static inline unsigned getHashValue(sampleprof::CallsiteLocation Val) {
131 return DenseMapInfo<std::pair<uint32_t, uint32_t>>::getHashValue(
132 std::pair<uint32_t, uint32_t>(Val.LineOffset, Val.Discriminator));
134 static inline bool isEqual(sampleprof::CallsiteLocation LHS,
135 sampleprof::CallsiteLocation RHS) {
136 return LHS.LineOffset == RHS.LineOffset &&
137 LHS.Discriminator == RHS.Discriminator &&
138 LHS.CalleeName.equals(RHS.CalleeName);
142 namespace sampleprof {
144 /// Representation of a single sample record.
146 /// A sample record is represented by a positive integer value, which
147 /// indicates how frequently was the associated line location executed.
149 /// Additionally, if the associated location contains a function call,
150 /// the record will hold a list of all the possible called targets. For
151 /// direct calls, this will be the exact function being invoked. For
152 /// indirect calls (function pointers, virtual table dispatch), this
153 /// will be a list of one or more functions.
156 typedef StringMap<uint64_t> CallTargetMap;
158 SampleRecord() : NumSamples(0), CallTargets() {}
160 /// Increment the number of samples for this record by \p S.
162 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
163 /// around unsigned integers.
164 void addSamples(uint64_t S) {
165 if (NumSamples <= std::numeric_limits<uint64_t>::max() - S)
168 NumSamples = std::numeric_limits<uint64_t>::max();
171 /// Add called function \p F with samples \p S.
173 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
174 /// around unsigned integers.
175 void addCalledTarget(StringRef F, uint64_t S) {
176 uint64_t &TargetSamples = CallTargets[F];
177 if (TargetSamples <= std::numeric_limits<uint64_t>::max() - S)
180 TargetSamples = std::numeric_limits<uint64_t>::max();
183 /// Return true if this sample record contains function calls.
184 bool hasCalls() const { return CallTargets.size() > 0; }
186 uint64_t getSamples() const { return NumSamples; }
187 const CallTargetMap &getCallTargets() const { return CallTargets; }
189 /// Merge the samples in \p Other into this record.
190 void merge(const SampleRecord &Other) {
191 addSamples(Other.getSamples());
192 for (const auto &I : Other.getCallTargets())
193 addCalledTarget(I.first(), I.second);
198 CallTargetMap CallTargets;
201 typedef DenseMap<LineLocation, SampleRecord> BodySampleMap;
202 class FunctionSamples;
203 typedef DenseMap<CallsiteLocation, FunctionSamples> CallsiteSampleMap;
205 /// Representation of the samples collected for a function.
207 /// This data structure contains all the collected samples for the body
208 /// of a function. Each sample corresponds to a LineLocation instance
209 /// within the body of the function.
210 class FunctionSamples {
212 FunctionSamples() : TotalSamples(0), TotalHeadSamples(0) {}
213 void print(raw_ostream &OS = dbgs(), unsigned Indent = 0) const;
214 void addTotalSamples(uint64_t Num) { TotalSamples += Num; }
215 void addHeadSamples(uint64_t Num) { TotalHeadSamples += Num; }
216 void addBodySamples(uint32_t LineOffset, uint32_t Discriminator,
218 BodySamples[LineLocation(LineOffset, Discriminator)].addSamples(Num);
220 void addCalledTargetSamples(uint32_t LineOffset, uint32_t Discriminator,
221 std::string FName, uint64_t Num) {
222 BodySamples[LineLocation(LineOffset, Discriminator)].addCalledTarget(FName,
226 /// Return the number of samples collected at the given location.
227 /// Each location is specified by \p LineOffset and \p Discriminator.
228 /// If the location is not found in profile, return error.
229 ErrorOr<uint64_t> findSamplesAt(uint32_t LineOffset,
230 uint32_t Discriminator) const {
231 const auto &ret = BodySamples.find(LineLocation(LineOffset, Discriminator));
232 if (ret == BodySamples.end())
233 return std::error_code();
235 return ret->second.getSamples();
238 /// Return the function samples at the given callsite location.
239 FunctionSamples &functionSamplesAt(const CallsiteLocation &Loc) {
240 return CallsiteSamples[Loc];
243 /// Return a pointer to function samples at the given callsite location.
244 const FunctionSamples *
245 findFunctionSamplesAt(const CallsiteLocation &Loc) const {
246 auto iter = CallsiteSamples.find(Loc);
247 if (iter == CallsiteSamples.end()) {
250 return &iter->second;
254 bool empty() const { return TotalSamples == 0; }
256 /// Return the total number of samples collected inside the function.
257 uint64_t getTotalSamples() const { return TotalSamples; }
259 /// Return the total number of samples collected at the head of the
261 uint64_t getHeadSamples() const { return TotalHeadSamples; }
263 /// Return all the samples collected in the body of the function.
264 const BodySampleMap &getBodySamples() const { return BodySamples; }
266 /// Return all the callsite samples collected in the body of the function.
267 const CallsiteSampleMap &getCallsiteSamples() const {
268 return CallsiteSamples;
271 /// Merge the samples in \p Other into this one.
272 void merge(const FunctionSamples &Other) {
273 addTotalSamples(Other.getTotalSamples());
274 addHeadSamples(Other.getHeadSamples());
275 for (const auto &I : Other.getBodySamples()) {
276 const LineLocation &Loc = I.first;
277 const SampleRecord &Rec = I.second;
278 BodySamples[Loc].merge(Rec);
280 for (const auto &I : Other.getCallsiteSamples()) {
281 const CallsiteLocation &Loc = I.first;
282 const FunctionSamples &Rec = I.second;
283 functionSamplesAt(Loc).merge(Rec);
288 /// Total number of samples collected inside this function.
290 /// Samples are cumulative, they include all the samples collected
291 /// inside this function and all its inlined callees.
292 uint64_t TotalSamples;
294 /// Total number of samples collected at the head of the function.
295 /// This is an approximation of the number of calls made to this function
297 uint64_t TotalHeadSamples;
299 /// Map instruction locations to collected samples.
301 /// Each entry in this map contains the number of samples
302 /// collected at the corresponding line offset. All line locations
303 /// are an offset from the start of the function.
304 BodySampleMap BodySamples;
306 /// Map call sites to collected samples for the called function.
308 /// Each entry in this map corresponds to all the samples
309 /// collected for the inlined function call at the given
310 /// location. For example, given:
318 /// If the bar() and baz() calls were inlined inside foo(), this
319 /// map will contain two entries. One for all the samples collected
320 /// in the call to bar() at line offset 1, the other for all the samples
321 /// collected in the call to baz() at line offset 8.
322 CallsiteSampleMap CallsiteSamples;
325 } // End namespace sampleprof
327 } // End namespace llvm
329 #endif // LLVM_PROFILEDATA_SAMPLEPROF_H_