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 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_PROFILEDATA_SAMPLEPROF_H_
16 #define LLVM_PROFILEDATA_SAMPLEPROF_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"
25 #include <system_error>
29 const std::error_category &sampleprof_category();
31 enum class sampleprof_error {
39 unsupported_writing_format,
45 inline std::error_code make_error_code(sampleprof_error E) {
46 return std::error_code(static_cast<int>(E), sampleprof_category());
49 inline sampleprof_error MergeResult(sampleprof_error &Accumulator,
50 sampleprof_error Result) {
51 // Prefer first error encountered as later errors may be secondary effects of
52 // the initial problem.
53 if (Accumulator == sampleprof_error::success &&
54 Result != sampleprof_error::success)
59 } // end namespace llvm
63 struct is_error_code_enum<llvm::sampleprof_error> : std::true_type {};
68 namespace sampleprof {
70 static inline uint64_t SPMagic() {
71 return uint64_t('S') << (64 - 8) | uint64_t('P') << (64 - 16) |
72 uint64_t('R') << (64 - 24) | uint64_t('O') << (64 - 32) |
73 uint64_t('F') << (64 - 40) | uint64_t('4') << (64 - 48) |
74 uint64_t('2') << (64 - 56) | uint64_t(0xff);
77 static inline uint64_t SPVersion() { return 103; }
79 /// Represents the relative location of an instruction.
81 /// Instruction locations are specified by the line offset from the
82 /// beginning of the function (marked by the line where the function
83 /// header is) and the discriminator value within that line.
85 /// The discriminator value is useful to distinguish instructions
86 /// that are on the same line but belong to different basic blocks
87 /// (e.g., the two post-increment instructions in "if (p) x++; else y++;").
89 LineLocation(uint32_t L, uint32_t D) : LineOffset(L), Discriminator(D) {}
90 void print(raw_ostream &OS) const;
92 bool operator<(const LineLocation &O) const {
93 return LineOffset < O.LineOffset ||
94 (LineOffset == O.LineOffset && Discriminator < O.Discriminator);
98 uint32_t Discriminator;
101 raw_ostream &operator<<(raw_ostream &OS, const LineLocation &Loc);
103 /// Representation of a single sample record.
105 /// A sample record is represented by a positive integer value, which
106 /// indicates how frequently was the associated line location executed.
108 /// Additionally, if the associated location contains a function call,
109 /// the record will hold a list of all the possible called targets. For
110 /// direct calls, this will be the exact function being invoked. For
111 /// indirect calls (function pointers, virtual table dispatch), this
112 /// will be a list of one or more functions.
115 typedef StringMap<uint64_t> CallTargetMap;
117 SampleRecord() : NumSamples(0), CallTargets() {}
119 /// Increment the number of samples for this record by \p S.
120 /// Optionally scale sample count \p S by \p Weight.
122 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
123 /// around unsigned integers.
124 sampleprof_error addSamples(uint64_t S, uint64_t Weight = 1) {
126 NumSamples = SaturatingMultiplyAdd(S, Weight, NumSamples, &Overflowed);
127 return Overflowed ? sampleprof_error::counter_overflow
128 : sampleprof_error::success;
131 /// Add called function \p F with samples \p S.
132 /// Optionally scale sample count \p S by \p Weight.
134 /// Sample counts accumulate using saturating arithmetic, to avoid wrapping
135 /// around unsigned integers.
136 sampleprof_error addCalledTarget(StringRef F, uint64_t S,
137 uint64_t Weight = 1) {
138 uint64_t &TargetSamples = CallTargets[F];
141 SaturatingMultiplyAdd(S, Weight, TargetSamples, &Overflowed);
142 return Overflowed ? sampleprof_error::counter_overflow
143 : sampleprof_error::success;
146 /// Return true if this sample record contains function calls.
147 bool hasCalls() const { return CallTargets.size() > 0; }
149 uint64_t getSamples() const { return NumSamples; }
150 const CallTargetMap &getCallTargets() const { return CallTargets; }
152 /// Merge the samples in \p Other into this record.
153 /// Optionally scale sample counts by \p Weight.
154 sampleprof_error merge(const SampleRecord &Other, uint64_t Weight = 1) {
155 sampleprof_error Result = addSamples(Other.getSamples(), Weight);
156 for (const auto &I : Other.getCallTargets()) {
157 MergeResult(Result, addCalledTarget(I.first(), I.second, Weight));
162 void print(raw_ostream &OS, unsigned Indent) const;
167 CallTargetMap CallTargets;
170 raw_ostream &operator<<(raw_ostream &OS, const SampleRecord &Sample);
172 typedef std::map<LineLocation, SampleRecord> BodySampleMap;
173 class FunctionSamples;
174 typedef std::map<LineLocation, FunctionSamples> CallsiteSampleMap;
176 /// Representation of the samples collected for a function.
178 /// This data structure contains all the collected samples for the body
179 /// of a function. Each sample corresponds to a LineLocation instance
180 /// within the body of the function.
181 class FunctionSamples {
183 FunctionSamples() : Name(), TotalSamples(0), TotalHeadSamples(0) {}
184 void print(raw_ostream &OS = dbgs(), unsigned Indent = 0) const;
186 sampleprof_error addTotalSamples(uint64_t Num, uint64_t Weight = 1) {
189 SaturatingMultiplyAdd(Num, Weight, TotalSamples, &Overflowed);
190 return Overflowed ? sampleprof_error::counter_overflow
191 : sampleprof_error::success;
193 sampleprof_error addHeadSamples(uint64_t Num, uint64_t Weight = 1) {
196 SaturatingMultiplyAdd(Num, Weight, TotalHeadSamples, &Overflowed);
197 return Overflowed ? sampleprof_error::counter_overflow
198 : sampleprof_error::success;
200 sampleprof_error addBodySamples(uint32_t LineOffset, uint32_t Discriminator,
201 uint64_t Num, uint64_t Weight = 1) {
202 return BodySamples[LineLocation(LineOffset, Discriminator)].addSamples(
205 sampleprof_error addCalledTargetSamples(uint32_t LineOffset,
206 uint32_t Discriminator,
207 const std::string &FName,
208 uint64_t Num, uint64_t Weight = 1) {
209 return BodySamples[LineLocation(LineOffset, Discriminator)].addCalledTarget(
213 /// Return the number of samples collected at the given location.
214 /// Each location is specified by \p LineOffset and \p Discriminator.
215 /// If the location is not found in profile, return error.
216 ErrorOr<uint64_t> findSamplesAt(uint32_t LineOffset,
217 uint32_t Discriminator) const {
218 const auto &ret = BodySamples.find(LineLocation(LineOffset, Discriminator));
219 if (ret == BodySamples.end())
220 return std::error_code();
222 return ret->second.getSamples();
225 /// Return the function samples at the given callsite location.
226 FunctionSamples &functionSamplesAt(const LineLocation &Loc) {
227 return CallsiteSamples[Loc];
230 /// Return a pointer to function samples at the given callsite location.
231 const FunctionSamples *findFunctionSamplesAt(const LineLocation &Loc) const {
232 auto iter = CallsiteSamples.find(Loc);
233 if (iter == CallsiteSamples.end()) {
236 return &iter->second;
240 bool empty() const { return TotalSamples == 0; }
242 /// Return the total number of samples collected inside the function.
243 uint64_t getTotalSamples() const { return TotalSamples; }
245 /// Return the total number of samples collected at the head of the
247 uint64_t getHeadSamples() const { return TotalHeadSamples; }
249 /// Return all the samples collected in the body of the function.
250 const BodySampleMap &getBodySamples() const { return BodySamples; }
252 /// Return all the callsite samples collected in the body of the function.
253 const CallsiteSampleMap &getCallsiteSamples() const {
254 return CallsiteSamples;
257 /// Merge the samples in \p Other into this one.
258 /// Optionally scale samples by \p Weight.
259 sampleprof_error merge(const FunctionSamples &Other, uint64_t Weight = 1) {
260 sampleprof_error Result = sampleprof_error::success;
261 Name = Other.getName();
262 MergeResult(Result, addTotalSamples(Other.getTotalSamples(), Weight));
263 MergeResult(Result, addHeadSamples(Other.getHeadSamples(), Weight));
264 for (const auto &I : Other.getBodySamples()) {
265 const LineLocation &Loc = I.first;
266 const SampleRecord &Rec = I.second;
267 MergeResult(Result, BodySamples[Loc].merge(Rec, Weight));
269 for (const auto &I : Other.getCallsiteSamples()) {
270 const LineLocation &Loc = I.first;
271 const FunctionSamples &Rec = I.second;
272 MergeResult(Result, functionSamplesAt(Loc).merge(Rec, Weight));
277 /// Set the name of the function.
278 void setName(StringRef FunctionName) { Name = FunctionName; }
280 /// Return the function name.
281 const StringRef &getName() const { return Name; }
284 /// Mangled name of the function.
287 /// Total number of samples collected inside this function.
289 /// Samples are cumulative, they include all the samples collected
290 /// inside this function and all its inlined callees.
291 uint64_t TotalSamples;
293 /// Total number of samples collected at the head of the function.
294 /// This is an approximation of the number of calls made to this function
296 uint64_t TotalHeadSamples;
298 /// Map instruction locations to collected samples.
300 /// Each entry in this map contains the number of samples
301 /// collected at the corresponding line offset. All line locations
302 /// are an offset from the start of the function.
303 BodySampleMap BodySamples;
305 /// Map call sites to collected samples for the called function.
307 /// Each entry in this map corresponds to all the samples
308 /// collected for the inlined function call at the given
309 /// location. For example, given:
317 /// If the bar() and baz() calls were inlined inside foo(), this
318 /// map will contain two entries. One for all the samples collected
319 /// in the call to bar() at line offset 1, the other for all the samples
320 /// collected in the call to baz() at line offset 8.
321 CallsiteSampleMap CallsiteSamples;
324 raw_ostream &operator<<(raw_ostream &OS, const FunctionSamples &FS);
326 /// Sort a LocationT->SampleT map by LocationT.
328 /// It produces a sorted list of <LocationT, SampleT> records by ascending
329 /// order of LocationT.
330 template <class LocationT, class SampleT> class SampleSorter {
332 typedef std::pair<const LocationT, SampleT> SamplesWithLoc;
333 typedef SmallVector<const SamplesWithLoc *, 20> SamplesWithLocList;
335 SampleSorter(const std::map<LocationT, SampleT> &Samples) {
336 for (const auto &I : Samples)
338 std::stable_sort(V.begin(), V.end(),
339 [](const SamplesWithLoc *A, const SamplesWithLoc *B) {
340 return A->first < B->first;
343 const SamplesWithLocList &get() const { return V; }
346 SamplesWithLocList V;
349 } // end namespace sampleprof
351 } // end namespace llvm
353 #endif // LLVM_PROFILEDATA_SAMPLEPROF_H_